Title of Invention	CLAMPING AND/OR BRAKING DEVICE
Abstract	The invention concerns a clamping and/or braking device with a housing, in which at least one plate-like element is held, which is supported, with a first end, opposite a stop area of the housing and which, with a second end, transfers clamping and/or braking forces to an object, or acts on a pressurizable element, which transfers clamping and/or braking forces to an object, wherein the plate-like element has at least one bending area which is convex in the starting state, which is constructed pressure-resistant and nevertheless elastically deformable so that the bending area forms an elastic element between the stop area of the housing and a pressurizing end of the plate-like element, wherein an essentially airtight pressure space is formed between the convex side of the at least one bending area of the at least one plate-like element and the housing, wherein the pressure space can be acted on with the excess pressure of a pressure medium which can be supplied to the housing, and wherein the at least one plate-like element and its at least one bending area are constructed in such a way that with an pressurization of the pressure space with excess pressure, as a result of a reduction of the curvature of the bending area to attain prespecified clamping and/or braking forces, a movement of the second end of the at least one pressurizable element (17) takes place in the direction of the base element (7), or an increase of the clamping and/or braking forces, which can be transferred to the object by the second end of the at least one pressurizable element, is brought about.

Title of Invention

CLAMPING AND/OR BRAKING DEVICE

Abstract

The invention concerns a clamping and/or braking device with a housing, in which at least one plate-like element is held, which is supported, with a first end, opposite a stop area of the housing and which, with a second end, transfers clamping and/or braking forces to an object, or acts on a pressurizable element, which transfers clamping and/or braking forces to an object, wherein the plate-like element has at least one bending area which is convex in the starting state, which is constructed pressure-resistant and nevertheless elastically deformable so that the bending area forms an elastic element between the stop area of the housing and a pressurizing end of the plate-like element, wherein an essentially airtight pressure space is formed between the convex side of the at least one bending area of the at least one plate-like element and the housing, wherein the pressure space can be acted on with the excess pressure of a pressure medium which can be supplied to the housing, and wherein the at least one plate-like element and its at least one bending area are constructed in such a way that with an pressurization of the pressure space with excess pressure, as a result of a reduction of the curvature of the bending area to attain prespecified clamping and/or braking forces, a movement of the second end of the at least one pressurizable element (17) takes place in the direction of the base element (7), or an increase of the clamping and/or braking forces, which can be transferred to the object by the second end of the at least one pressurizable element, is brought about.

Full Text	CLAMPING AND/OR BRAKING DEVICE The invention concerns a clamping and/or braking device. Clamping or braking devices are known in the most varied embodiments for the most varied application cases. Thus, a braking device of a linear guide is known in EP- A-0 936 366 that has a supporting body and can be moved along a guide track. The supporting body has brake shoes, which act on the two longitudinal sides. The supporting body is shaped like an H and has a thin, elastically flexible crosslink and two lower legs, with which it grips the guide track. A brake shoe is located between a lower leg and the guide track. The supporting body is provided with two upper legs, which, together, form a holding space with the crosslink, in which a force-producing means, acting on the upper leg, is provided. This can be hydraulically or pneumatically actuatable toggle lever mechanics or a piezoelectric actuator. Moreover, a hydraulically or pneumatically actuatable wedge valve can be provided as a force transducer, which is conducted in a formed space, which tapers in the longitudinal direction of the brake device, between the upper legs of the supporting body. In all cases, a bending of the elastic crosslink takes place due to the force pressurizatioin of the two upper legs, so that the two lower legs are moved inwards with the brake shoes or apply pressure on the guide track with a large force. The disadvantage with this known brake device, in connection with the use of an electromechanical transducer such as a piezoelectric element, is, in particular, its sensitivity with respect to vibrations or other mechanical loads. The use of a toggle lever or a wedge valve, just like an electromechanical transducer, means a high installation or production expense. In addition, there is, in particular with clamping devices, the requirement of sufficiently high clamping forces, which, with known devices, can be implemented only with a relatively high construction and thus financial expense. From US 5,855,446, a hydraulic clamping bushing is known, which is aligned on a shaft and can be connected to it, for example, in a stationary manner. The bushing essentially has a stable bushing body, which is located at a distance around a drive shaft. Adjacent to these bushing bodies and facing the shaft, a chamber which can be acted on with pressure is provided. A side wall of this chamber, which extends essentially parallel to the shaft is used here, at the same time, as a braking element, which with the action of pressure on the chamber is pressed against the shaft by the expansion of the chamber, in order to produce a friction-locking connection. A Σ-shaped formation of the laterally adjacent walls of the chamber is meant to prevent the bushing from aligning crooked with respect to the wall when the pressure acts on chamber. The X-shaped side walls of the chamber make possible, in the case of pressure pressurization, an expansion of these side walls in a radial direction toward the shaft, before the increasing chamber pressure also presses the chamber wall, running parallel to the shaft, against the shaft. Thus, the bushing can be aligned at right angles to the shaft axis, before the tortional connection is produced. This clamping device does not have a favorable power transmission for the creation of a higher pressing force. Furthermore, in its shape and in particular., in its placement possibility relative to the bushing body, the chamber is limited. The braking effect can be attained here only by acting on the chamber with excess pressure, and the actual braking element, which must perhaps transfer high driving-forces, is not firmly connected to the bushing body, but rather only via the inevitably relatively unstable pressure chamber. From WO 01/34990 A1 from the applicant, a clamping and/or braking device is known, in which a chamber which can be acted on with pressure is provided on a basic body; in at least one partial area of at least one deformable or tension-resistant and/or pressure-resistant wall, the chamber is limited. The limitation of the chamber opposite the wall can also be constructed like the first wall. However, it can also be a rigid part of a body. Preferably, the walls lie at a relatively small distance from one another. The forces resulting from the deformation of the chamber are conducted, at least in part, in the direction of or along the wall and in the area of the connection of the wall to a basic body are introduced into the lattter. If one selects the point of attack of such forces on the basic body, and if this basic body is, at least partially, elastically deformable, then the forces can be transferred, for example, into the clamping or braking areas via this basic body on other sites of the basic body. A corresponding braking or clamping means in these areas can then be moved, by means of the forces, into a pressurizing position or out of it, so as to brake or release a guide element or an element which has to be clamped or braked. Both applied excess or reduced pressure in the chamber can be used thereby, in order to introduce both tractive and compressive forces to the basic body. Of course, before and after the introduction of force, the clamping and/or braking areas are still engaged with the guide element or the element to be clamped or braked, wherein, however, changes in the pressurizing forces between the clamping and/or braking areas and the other element result. This known clamping and/or braking device is based on the knowledge that when acted on by a reduced or excess pressure, a suitable chamber tends to a deformation. If this chamber, to a great extent, is formed by at least one approximately plane wall, then the excess or reduced pressure in the chamber first causes a deformation in a first direction running essentially Perpendicular to this wall. In order to yield to the deformation (expansion or contraction) in this first direction, the result from this, in a correspondingly reverse manner, is a contraction or expansion of the chamber in a second direction generally running perpendicular; to the first direction (that is, essentially parallel to the wall). The fact is used thereby that low forces or deformations in the first direction produce large forces in the second direction, which can be used to break or clamp or to release pretensioned clamping or braking devices. On the basis of this state of the art, the goal of the invention is to create a clamping and/or braking device, which can be produced with lower construction expense and with which sufficiently high braking or clamping forces can be produced in a simple manner. In contrast to the disclosures of US 3363027 and US 45443887, the present invention provides a clamping and/or braking device, wherein a plate-shaped element has radial slots opening inwards, and second end of the element is formed by the inner end of the element, or the element has radial slots opening outwards, and the second end of the element is formed by the outer end of the element. Further, at least one sealing element is provided at the inner and/or outer surfaces in relation to the pressure space of the element, at least in the area of the slots. Accordingly, the invention provides clamping and/or braking device comprising a housing, in which at least one ring-shaped, plate-shaped element is held, which element: is supported with a first end with respect to a stop area of the housing and which with a second end transmits clamping and/or braking forces to an object or a pressurisable element, which transmits clamping and/or braking forces to the object, wherein a) said at least one ring-shaped, plate-shaped element has at least one bending area which is convex in the initial state and is formed so as to be pressure-resistant and yet elastically bendable so that the bending area forms a resilient element between the stop area of the housing and a pressurisable end of the ring-shaped, plate-shaped element, b) a substantially tight pressure space is formed between the convex side of said at least one bending area of said at least one ring-shaped, plate-shaped element and the housing, which space can be acted upon by the excess pressure of a pressure medium which can be supplied to the housing, and c) said at least one ring-shaped, plate-shaped element and its at least one bending area are formed so that, when the pressure space is acted upon by excess pressure, as a result of a reduction of the curvature of the bending area, in order to obtain predetermined clamping and/or braking forces, a movement of the second end of said at least one ring-shaped, plate-shaped element or a movement of the second end of said at least one ring-shaped, plate-shaped element together with the pressurisable element takes place in the direction of the object or an increase in the clamping and/or braking forces transmissible to the object by the second end of said at least one ring-shaped, plate-shaped element or the pressurisable element is brought about, characterised in that i) said at least one ring-shaped, plate-shaped element has radial slots which are open inwards, wherein the second end of the ring-shaped, plate-shaped element is formed by the inner end of the ring-shaped, plate-shaped element, or ii) said at least one ring-shaped, plate-shaped element has radial slots which are open outwards, wherein the second end of the ring-shaped, plate-shaped element is formed by the outer end of the ring-shaped, plate-shaped element, and iii) one or a plurality of sealing element(s) is/are provided at the inner and /or outer surfaces, in relation to the pressure space, of said at least one ring- shaped, plate-shaped element, at least in the area of the slots. The invention is based on the knowledge that by means of at least one plate-like element, which is located in a housing and has a convex bending area, a clamping and/or braking device can be produced at low cost; this device can also produce very high clamping and/or braking forces by means of an only gaseous pressure medium-that is, pneumatically. However, it is clear that a hydraulic actuation of the device is also possible. The function of the device is guaranteed by the convex formation of at least one bending area of the plate-like element, with application on its convex side of an excess pressure from a pressure medium, wherein a corresponding pressure space is provided on the side of the bending area, which curves convexly outwards. With pressure acting on the bending area, its curvature is reduced; so that the expansion of the plate-like element between two ends is increased, of which one is supported on the housing and the other acts, directly or indirectly, via a pressurizable element, on the object to be clamped or braked. The plate- like element is thereby so pressure-resistant and constructed so elastically deformable in the at least one bending area that between the two ends, an elastic element is formed. The pressure resistance of the plate-like element must be designed in such a way that when a predetermined, maximum permissible force is exerted on the second end (pressurizing end), a sharp bending does not occur. Of course, a corresponding free space, which makes possible a sufficient bending of the bending area, must be present on the concave side of the bending area, turned away from the pressure application side. This free space can be connected to the surroundings—that is, to the air pressure of the surroundings. However, it can also be closed airtight so that the bending of the bending area must take place, against an increasing pressure, in the free space. Contrary to the known device of the applicant, it is possible, with these embodiments, to produce or to change clamping and/or braking forces, without hereby having to deform an essentially rigid body. In this way, aside from a simple construction, a small model results. The device is, moreover, simple to produce, since only the plate-like element must be placed in the housing. Contrary to the known clamping bushings, which have relatively soft walls, and which increase the distance between a pressurizable element and a base element when acted on with excess pressure, it is also possible with the device in accordance with the invention to produce a predetermined clamping and/or braking force, with which the object to be clamped or braked is acted on, even in a pressure-less state during a corresponding pretensioned installation of the device in the complete device. In this way, for example, a control of the device is possible, in such a way that a change between a braked (in the pressure-less state) movement of the pressurized object and a complete clamping of the object (with a sufficient pressurization) results. The more frequent use of the device in accordance with the invention, however, is the one where in the pressure-less starting state, the object is not acted on and with a pressurization of the device, is braked or clamped. With a linearly functioning clamping and/or braking device, the at least one plate-like element can have a, for example, rectangular shape, wherein the entire element can be convexly curved between two edges. The first and the second ends are then formed by those edges or end areas between which the curvature runs. At least in the area of the bending (if the entire plate- shaped element is not bent), the side edges must be essentially sealed off with respect to the housing (a small leakage can be tolerated, under certain circumstances, if, for example, compressed air is used as the pressure medium and the required pressure can be attained and maintained in spite of the leakage) According to one development of the invention, a pressurizable element is provided, which is constructed in one piece with the housing and as a pant of the housing, or which is constructed as a part connected to the housing in a detachable manner, wherein the pressurizable element is constructed deformably in such a way that with a pressure application of the pressure space, a movement of at least one section of the pressurizable element takes place in the direction of the object or the transferable clamping and/or braking forces, produced by the at least one plate-like element, are transferred to the object. With such a deformable pressurizable element, the pressure space can be sealed of in a simple manner, with respect to the at least one plate-like element—namely on the pressurizing edge or the second end of the plate-like element, with respect to the pressurizable element. Basically, however, a pressurizable element is not connected to the housing can also be used, which, for example, can be constructed correspondingly large for the distribution of the pressing force on a greater surface. Moreover, the pressurizable element can be used to adapt the pressing surface (constructed then on the pressurizable element) to the shape of the object. In a development of the invention, the first end of the at least one plate-like element can be connected to the housing, especially if in the realization of a linearly acting clamping and/or braking device, a pressurizable element not connected to the housing is used or the object is acted on directly by the second end of the at least one plate-like element. In the preferred embodiment of the invention, the first end of the at least one plate-like part, however, is supported, without a firm connection, against the housing. With the presence of a pressurizable element, the second end of the at least one plate-like part is also preferably supported, without a firm connection, against the pressurizable element. In this way, a simple installation of the device results. According to one embodiment of the invention, the at least one-plate-shaped element is annular, preferably, circular, so as to create a device that makes possible the clamping of bar- or rod-shaped objects, in particular, in the cross section of circular-cylindrical objects. The ring-shaped, plate-like element can be shaped convexly, in the starting state, via essentially the entire radial cross section, wherein essentially the entire ring-shaped wall of the ring-shaped, plate-like element serves as the bending area Such a plate-like element can be produced very simply and at low cost and can be used also for a large number of variants. The at least one ring-shaped, plate-like element preferably has radial slits that are open inwardly or outwardly, wherein, preferably, the second end-that is, the pressurizing end of the ring-shaped, plate-like element—is formed by the inside or outside end of the ring-shaped, plate- like element. The slits preferably extend to just before the opposite end of the ring and are present in such a number that proceeding from the closed ring area, individual sections extend inwardly or outwardly. These sections reduce the required deformation of the ring in the azimuth direction, if the curvature of the convex bending area is reduced during pressurization. With such slit, ring-shaped, plate-like elements, it is possible to provide one or more sealing elements, preferably, in the shape of a deformable layer, on a part or on the entire surface of the plate-like element, on the inside and/or outside surfaces of the plate-like elements, relative to the pressure space, at least in the area of the slits. In this way, a common pressure space can be used for the individual sections between the slits. The sealing of the slits can, for example, take place by vulcanizing on a relatively hard, but nevertheless, sufficiently deformable rubber layer. Such a layer can be produced even on the side of the ring-shaped, plate-like element, turned away from the pressurization, without the danger of loosening the layer during a pressurization. In the preferred embodiment of the invention, the bending of the at least one bending area of the at least one plate-like element is limited in such a way that after the discontinuation of the pressurizing of the pressure space with excess pressure as a result of the elastic effect of the at least one bending area, it returns to the starting state. One designates, as the starting state, the pressure-less state, wherein in this state also, depending on the dimensioning or installation of the clamping and/or braking device, the at least one bending area can be pretensioned. A corresponding stop for the bending area can be formed, for example, by an inside housing wall. According to one development of the invention, several plate-like elements, arranged essentially parallel to one another, can be provided, whose second ends have a predetermined distance to one another, in order to transfer clamping and/or braking forces to the object, via a prespecified expanded area, wherein for each plate-like element, a separate pressure space or for several or all plate-like elements, a common pressure space can be formed. When using several plate-like elements, at least one pair of plate-like elements can be provided, whose first and second ends are directly adjacent or at a close distance to one another, and whose convex bending areas run convexly outwards, relative to the other plate-like element of the pair of plate-like elements, wherein a common pressure space is provided for the pressurization of the bending areas of the two plate-like elements of a pair. This variant offers the advantage that the two plate-like elements are pressed against one another during a pressurization and so the space required between the two elements can be sealed off with lower pressure in a simple manner. For example, the rubber coating mentioned in the preceding can be provided inside or can be a sealing element connected to the inside surfaces of the plate-like elements. In addition, the plate-like elements of a pair can be designed in such a way that they lie close to one another, with at least one partial area of the sides facing one another in an ending state when acted on with an excess pressure greater or equal to a prespecified maximum pressure, wherein the ending state is defined by a suitable formation of the bending areas in such a way that from the ending state, an automatic return to the pressure-less starting state takes place. In this way, a plate-like element is used as a stop for the at least one bending area of the other plate- like element. According to one embodiment of the invention, a pressurizable element can be provided, which is constructed rigid in the entire area in which the several plate-like elements are active. In this way, a more uniform transfer of the clamping and/or braking forces can be attained on the object. With all embodiments of the invention, the creation of the clamping and/or braking forces, however, takes place exclusively or at least, for the most part, predominantly due to one pressurization and the bending hereby produced and thus the change of the effective expansion of the plate-like elements between the two ends. This is also true for the case that one surface of the pressurizable element is acted on completely or partially with pressure, if the bending area(s) of the plate-like elements are acted on with pressure. The forces hereby produced, which are comparable with the forces arising with common clamping bushings, can be practically neglected however. In another embodiment of the invention, the housing and the pressurizable element can be designed as essentially H-shaped bodies, wherein the at least one plate-like element and the pressure space are provided between the essentially parallel, upper legs of the H-shaped body, wherein clamping and/or braking areas are provided on the essentially parallel, lower legs of the H-shaped body for the transfer of the clamping and/or braking forces to the object and wherein the H-shaped body is elastically deformable in the area of the middle crosslink and/or the connecting areas of the middle crosslink with the legs of the H. In a similar manner, the housing and the pressurizable element can be designed as essentially U-shaped bodies, wherein the at least one plate-like element and the pressure space are provided between the essentially parallel legs of the U-shaped body, wherein clamping and/or braking areas are provided on the essentially parallel legs of the H-shaped body for the transfer of the clamping and/or braking forces on the object and wherein the U-shaped body is elastically deformable in the area of the base of the U and/or in the area of the legs of the U. Other embodiments of the invention can be deduced from the preferred embodiments described hereinafter. The invention is explained in more detail below, with the aid of the embodiment examples shown in the accompanying drawing, wherein - Figure 1, a longitudinal section (Fig. 1a) and a detail enlargement (Fig. 1b) of a first embodiment of a clamping and/or braking device, according to the invention, for the pressurizing of a circular-cylindrical object, using a ring-shaped, plate-like element; Figure 2, a top view (Fig. 2a) of the ring-shaped, plate-like element in Figure 1 and a detail enlargement (Fig. 2b) in sectional view along the line A-A in (Fig. 2a) ; Figure 3, a longitudinal section (Fig. 3a) and a detail enlargement (Fig. 3b) of a second embodiment of a clamping and/or braking device according to the invention for the pressurization of a circular-cylindrical object, using several pairs of ring-shaped, plate-like elements ; Figure 4, a detail enlargement of a third embodiment of a clamping and/or braking device according to the invention, analogous Figure 3, but using a ring-shaped pressurizable element; Figure 5, a detail enlargement of a fourth embodiment of a clamping and/or braking device according to the invention, analogous Figure 4, but using a pressurizable element, constructed as one piece with the housing; and Figure 6, a schematic cross section through a fifth embodiment of a clamping and/or braking device according to the invention for the realization of a linear guide. The embodiment of a clamping and/or braking device 1, shown in Figure 1 in a schematic longitudinal section, has a ring-shaped housing 3, which consists of a first part 5 with a ring- shaped recess 7 and a second part 9, which is connected to the first part 5, for example, screwed to it. In the recess 7, between the first and second housing part 5, 9, a ring-shaped, plate-like element 11 is located. The ring-shaped, plate-like element 11 is shaped slightly convex in the radial section and applies pressure on the circumferential wall of the ring-shaped recess 7 of the first housing part 5 with its outside end or its outside boundary 1 la As can be seen from Figure lb, the ring-shaped, plate-like element 11, consisting, for example, of a steel sheet, can be connected, on one side, to a sealing element 13, for example, a relatively hard, but still sufficiently deformable rubber ring. The ring-shaped, plate-like element 11 is, as shown in Figures 2a and 2b, provided with a large number of slits 14, which proceeding from an outside boundary area 11c, which is also closed in the shape of a ring, run radially inwards and open toward the inside. The ring-shaped, plate-like element 11 defines, together with the sealing element 13, on its convex side, together with the inside wall of the first housing part 7, a pressure space 15, to which a pressure medium can be supplied, for example, compressed air. Of course, however, a liquid pressure medium can also be used. The pressure space 15 is constructed open toward the inside in the embodiment shown in Figure 1 and must be sealed off, with respect to the object 17 to be acted on, for example, a rotatable shaft. This can take place by means of corresponding sealing elements 19, which can be designed as O rings. The O rings 19 can be taken up in grooves in the inside walls of the first and second housing part 5, 9. The ring-shaped, plate-like element 11 lies close to the inside wall of the second housing part 9 in the embodiment example shown in Figure 1, with its outside and inside boundaries 11a, 11b, wherein the sealing element sufficiently seals off the space between the concave surface of the element 11 and the inside wall of the housing part 9. In this respect, an annular area 13a, 13b of the sealing element can be constructed on the outside and inside boundary. The inside annular area 13b can be designed so far, in its radial expansion, that it lies close to the inside wall of the housing part 9, at least with a partial area over the entire movement path of the element 11. The space between the concave side of the element 11 and the housing part 9 can also be connected to the surroundings, via one or more (not depicted) canals. If the pressure medium is conducted under a certain pressure to the pressure space 15, via one or more (not depicted) supply canals, then the ring-shaped, plate-like element 11 is bent in the direction of the second housing part 9-that is, the curvature is reduced. In this way, the sections of the element 11, stretching inwards between the slits 14, are moved, with its inside boundary 11b, further inwards in the direction of the object 17, so that a desired braking or clamping force can be exerted on the object by a certain pressure of the pressure medium. The element 11 must, of course, be so dimensioned and be made of such a material that at least in one bending area, there is a sufficient deformability and moreover, the element 11 is constructed sufficiently pressure-resistant as a whole that even with the maximum producible clamping or braking force, which acts on the inside end of the element 11 or is exerted on the object 17 by it, no sharp bending of the element 11 or even a plastic deformation occur. The inside wall of the second housing part 9 is also used as a stop for the ring- shaped, plate-like element 11, so that even with high pressures, an abrupt reverting of the convex curvature to a concave curvature cannot occur. Moreover, the inside wall of the second housing part 9 and/or the ring-shaped, plate-like element 1 or the sealing element 13 can be constructed in such a way that the cuivature of the element 11 is reduced, as a maximum, so much that with a subsiding of the pressure, the elastic effect of the element 11 ensure that the element 11 again returns to the curvature present in the pressure-less starting state. In this respect, the inside wall of the housing part 9 can be constructed, for example, slightly convex in the direction of the element 11 or one or more stop elements can be provided on the inside wall of the housing part 9 or on the element 11 or on the sealing element 13. At this point, it should be noted that the sealing element can, of course, also be provided on the outside convex side of the element 11. In this case, it is also possible to use a loose sealing element, not connected to the element 11, for example, a separate, ring-shaped sealing disk made of rubber or plastic. The embodiment of a clamping and/or braking device shown in Figure 3 is similar to the embodiment in Figure 1. Instead of a single ring-shaped, plate-like element 11, five pairs of ring-shaped, plate-like elements 11, as a whole, are, however, provided in this embodiment. In this way, ten times the braking or clamping forces can be transferred to the object 17 with the same pressure of the pressure medium. The two ring-shaped, plate-like elements 11 of a pair are placed thereby in such a way that their concave sides oppose each other. In this way, a space sealed-off with respect to the pressure space 15, in which the elements 11 of the pairs of elements, sealed off with respect to each other, is formed, in a simple manner, between each pair of elements 11. With a pressurization of the pressure space 15 with the pressure of the pressure medium, the slit walls of the elements 11 are there to be bent toward one another. Since the inside ends 1 lb of the elements 11 of a pair move jointly, a sealing off of the space between the elements 1 can be reliably attained with simple means. The outside boundaries of the elements 11 can, of course, also be held, for the fixing, by suitable means in the housing 3, for example, in grooves in the circumferential wall of the cylindrical recess 7 of the first housing part 5. The two elements 11 of a pair can, of course, also be connected to one another-for example, they can be locked together. The embodiment of a clamping and/or braking device 1, according to Figure 4, differs from the embodiment shown in Figure 3 merely in that the inside ends 1 lb of the elements 11 do not apply pressure directly on the object 17 to be braked or to be clamped, but rather, via a ring- shaped pressurizable element 21, which is located inside the housing 3. The pressurizable element 21 is so deformed by the forces exerted by the pairs of ring-shaped, plate-like elements 11 —in particular, the inside diameter of the pressurizable element 21 is reduced to such an extent that the forces are transferred, at least partially, to the object 17. This embodiment offers the advantage that the sealing off of the pressure space 15 between the housing and the pressurizable element 21 can take place—for example, again via the sealing elements 19 in the form of O rings. As can be seen from Figure 5, in which another embodiment of a clamping and/or braking device is shown, it is also possible to provide a pressurizable element 21, constructed in an integrated manner with the housing 3, instead of a separate pressurizable element. In the case shown, the recess 7 in the first housing part 5 is designed in such a manner that a thin inside wall is formed, which forms the pressurizable element 21. The wall must be so thin that a sufficient deformation can be guaranteed when forces are exerted by the pairs of ring-shaped, plate-like elements 11 and thus a sufficient transfer of these forces to the object 17. The sealing off of the pressure space 15 can take place here in that the thin wall or the pressurizable element 21 is connected to the second housing part 9 in an essentially airtight manner. For the sealing, a sealing element 19, for example, in the form of an O ring, can again be used. Of course, such a clamping and/or braking device can also be designed in such a way that the corresponding forces are transferred to an object on a point-like, linear, or non-ring-shaped closed surface, for example, for the production of a clamping and/or braking device for a linear guide. If one does not interpret the representation in Figure 5 as an excerpt from an essentially rotation-symmetrical representation, but rather as an excerpt from a representation with a (for example, rectangular) housing 3, in which rectangular, plate-like elements 11 are placed, then a clamping and/or braking device is formed for the pressurization of the surface of an object 17, in which, for example, it may be a track of a linear guide. The housing 3 can, for example, be mounted on a carriage, not depicted in more detail, conducted by means of the object 17 designed as a track. The carriage can grip the track so that the exertion even of high forces on the surface of the object is possible, without lifting the carriage off the track. The mode of functioning of, for example, rectangular, plate-like elements can be deduced analogous to the preceding statements in connection with the annular, plate-like elements. If a pressurizable element 21 is not used with such an embodiment, then the plate-like elements 1 can be held, with their inside ends 1 la, in the housing or connected firmly with it (one piece or detachable). Of course, a sealing off of the pressure space 15, with respect to the object 17, must then again take place. The lateral edges or areas of the rectangular, plate-like elements must also be sealed off to create a pressure space or a "pressure-less" space between the pairs of plate-like elements. The embodiment according to Figure 6 is also a version of a clamping and/or braking device 1, with which a linear guide can be realized. The first housing part 5 is constructed, in this case, with an H-shaped cross section, wherein between the upper legs of the H, a pair of, for example, rectangular, plate-like elements 11 is provided. Since such elements 11 need not be provided with slits, it is possible, of course, to also dispense with corresponding sealing elements. The pressure space 15 is, in turn, formed outside the pair of the plate-like elements 11. In a pressurization of the pressure space 15, a deformation of the H-shaped housing part 5 is produced, in particular, in the area of the middle crosslink of the H and the transition areas between the crosslink and the lateral legs of the H. In this way, the rigidly constructed, lower legs of the H are moved inwards in the direction of the intermediately placed object 17 and transfer corresponding braking or clamping forces to the object. In this respect, it is possible to provide clamping and/or brake shoes 23 on the insides of the lower legs of the H. If instead of an H-shaped housing part 5, a U-shaped housing is used, in which one or more (for example, rectangular) plate-like elements, are provided between the legs of the U, with these elements pressing the legs of the U toward the outside with a pressurization, then an "active loosening" of an object, for example, with a linear guide, can be realized. Of course, this can also be attained with an H-shaped housing in that the brake shoes are located on the outsides of the lower legs of the H and they apply pressure on the object, for example, in a groove. Conversely, an "active clamping or braking" can also be produced with a U-shaped housing, if the brake shoes are located on the outsides of the legs of the U and correspondingly apply pressure on the object. Finally, it should be pointed out that of course, individual features which are described in the preceding only in connection with a specific embodiment can also be combined, if reasonable, with other embodiments also. I CLAIM : 1. Clamping and/or braking device comprising a housing, in which at least one ring-shaped, plate-shaped element is held, which element is supported with a first end with respect to a stop area of the housing and which with a second end transmits clamping and/or braking forces to an object or a pressurisable element, which transmits clamping and/or braking forces to the object, wherein a) said at least one ring-shaped, plate-shaped element has at least one bending area which is convex in the initial state and is formed so as to be pressure-resistant and yet elastically bendable so that the bending area forms a resilient element between the stop area of the housing and a pressurisable end of the ring-shaped, plate-shaped element, b) a substantially tight pressure space is formed between the convex side of said at least one bending area of said at least one ring-shaped, plate-shaped element and the housing, which space can be acted upon by the excess pressure of a pressure medium which can be supplied to the housing, and c) said at least one ring-shaped, plate-shaped element and its at least one bending area are formed so that, when the pressure space is acted upon by excess pressure, as a result of a reduction of the curvature of the bending area, in order to obtain predetermined clamping and/or braking forces, a movement of the second end of said at least one ring-shaped, plate-shaped element or a movement of the second end of said at least one ring-shaped, plate-shaped element together with the pressurisable element takes place in the direction of the object or an increase in the clamping and/or braking forces transmissible to the object by the second end of said at least one ring- shaped, plate-shaped element or the pressurisable element is brought about, characterised in that i) said at least one ring-shaped, plate-shaped element has radial slots which are open inwards, wherein the second end of the ring-shaped, plate-shaped element is formed by the inner end of the ring-shaped, plate-shaped element, or ii) said at least one ring-shaped, plate-shaped element has radial slots which are open outwards, wherein the second end of the ring-shaped, plate-shaped element is formed by the outer end of the ring-shaped, plate-shaped element, and iii) one or a plurality of sealing element(s) is/are provided at the inner and /or outer surfaces, in relation to the pressure space, of said at least one ring- shaped, plate-shaped element, at least in the area of the slots. 2. Device as claimed in Claim 1, wherein the ring-shaped, plate-shaped element acts on a pressurisable element, which is formed in one piece with the housing and as part of the housing or as a part connected to the housing in a detachable manner, the pressurisable element being formed in a flexible manner such that, when the pressure space is pressurised, a movement at least of one portion of the pressurisable element takes place in the direction of the object or the transmissible clamping and/or braking forces produced by said at least one ring-shaped, plate-shaped element are transmitted to the object. 3. Device as claimed in Claim 1 or 2, wherein the first end of the at least one ring- shaped, plate-shaped element is connected to the housing. 4. Device as claimed in any one of the preceding Claims, wherein the first end of said at least one ring-shaped, plate-shaped element is supported without a firm connection against the housing and, with the presence of a pressurisable element, the second end of said at least one ring-shaped, plate-shaped element is preferably also supported without a firm connection against the pressurisable element. 5. Device as claimed in any one of the preceding Claims, wherein said at least one ring-shaped, plate-shaped element is formed in the shape of a circular ring. 6. Device as claimed in any one of the preceding Claims, wherein the ring-shaped, plate-shaped element is formed so as to be convex over substantially the entire radial cross section in the initial state, substantially the entire ring-shaped wall of the ring- shaped, plate-shaped element serving as a bending area. 7. Device as claimed in any one of the preceding Claims, wherein said one or said plurality of sealing element(s) is/are provided in the form of a flexible layer on a part or on the entire surface of the ring-shaped, plate-shaped element. 8. Device as claimed in any one of the preceding Claims, wherein the bending of said at least one bending area of said at least one ring-shaped, plate-shaped element is limited such that, after discontinuation of the action on the pressure space by excess pressure, as a result of the resilient action of said at least one bending area, this is moved back into the initial state. 9. Device as claimed in any one of the preceding Claims, wherein a plurality of ring- shaped, plate-shaped elements are provided, the second ends of which elements have a predetermined spacing in order to transmit clamping and/or braking forces to the object over a predetermined extensive area ; and a separate pressure space is formed for each ring-shaped, plate-shaped element or a common pressure space is formed for a respective plurality of or all ring-shaped, plate-shaped elements. 10. Device as claimed in any one of the preceding Claims, wherein at least one pair of ring-shaped, plate-shaped elements is provided, the first and second ends of which are directly adjacent or at a close spacing from one another and the convex bending areas of which in each case extend convexly outwards, relative to the respective other ring-shaped, plate-shaped element of the pair ; and a common pressure space is provided for acting on the bending areas of the two ring-shaped, plate-shaped elements of a pair. 11. Device as claimed in Claim 10, wherein the ring-shaped, plate-shaped elements are formed so that, in a final state, when they are acted upon by an excess pressure which is greater than or equal to a predetermined maximum pressure, they lie against one another with at least a partial area of the facing sides, wherein the final state is defined by a suitable formation of the bending areas so that an automatic return from the final state to the pressureless initial state takes place. 12. Device as claimed in any one of Claims 9 to 11, wherein a pressurisable element is provided which is formed so as to be rigid in the entire area in which the plurality of ring-shaped, plate-shaped elements act. The invention concerns a clamping and/or braking device with a housing, in which at least one plate-like element is held, which is supported, with a first end, opposite a stop area of the housing and which, with a second end, transfers clamping and/or braking forces to an object, or acts on a pressurizable element, which transfers clamping and/or braking forces to an object, wherein the plate-like element has at least one bending area which is convex in the starting state, which is constructed pressure-resistant and nevertheless elastically deformable so that the bending area forms an elastic element between the stop area of the housing and a pressurizing end of the plate-like element, wherein an essentially airtight pressure space is formed between the convex side of the at least one bending area of the at least one plate-like element and the housing, wherein the pressure space can be acted on with the excess pressure of a pressure medium which can be supplied to the housing, and wherein the at least one plate-like element and its at least one bending area are constructed in such a way that with an pressurization of the pressure space with excess pressure, as a result of a reduction of the curvature of the bending area to attain prespecified clamping and/or braking forces, a movement of the second end of the at least one pressurizable element (17) takes place in the direction of the base element (7), or an increase of the clamping and/or braking forces, which can be transferred to the object by the second end of the at least one pressurizable element, is brought about.

Full Text

CLAMPING AND/OR BRAKING DEVICE
The invention concerns a clamping and/or braking device.
Clamping or braking devices are known in the most varied embodiments for the
most varied application cases. Thus, a braking device of a linear guide is known in EP-
A-0 936 366 that has a supporting body and can be moved along a guide track. The
supporting body has brake shoes, which act on the two longitudinal sides. The
supporting body is shaped like an H and has a thin, elastically flexible crosslink and two
lower legs, with which it grips the guide track. A brake shoe is located between a lower
leg and the guide track. The supporting body is provided with two upper legs, which,
together, form a holding space with the crosslink, in which a force-producing means,
acting on the upper leg, is provided. This can be hydraulically or pneumatically
actuatable toggle lever mechanics or a piezoelectric actuator. Moreover, a hydraulically
or pneumatically actuatable wedge valve can be provided as a force transducer, which
is conducted in a formed space, which tapers in the longitudinal direction of the brake
device, between the upper legs of the supporting body. In all cases, a bending of the
elastic crosslink takes place due to the force pressurizatioin of the two upper legs, so
that the two lower legs are moved inwards with the brake shoes or apply pressure on
the guide track with a large force.
The disadvantage with this known brake device, in connection with the use of an
electromechanical transducer such as a piezoelectric element, is, in particular, its
sensitivity with respect to vibrations or other mechanical loads.
The use of a toggle lever or a wedge valve, just like an electromechanical
transducer, means a high installation or production expense.
In addition, there is, in particular with clamping devices, the requirement of
sufficiently high clamping forces, which, with known devices, can be implemented only
with a relatively high construction and thus financial expense.
From US 5,855,446, a hydraulic clamping bushing is known, which is aligned on
a shaft and can be connected to it, for example, in a stationary manner. The bushing
essentially has a stable bushing body, which is located at a distance around a drive
shaft. Adjacent to these bushing bodies and facing the shaft, a chamber which can be
acted on with pressure is provided. A side wall of this chamber, which extends
essentially parallel to the shaft is used here, at the same time, as a braking element,
which with the action of pressure on the chamber is pressed against the shaft by
the expansion of the chamber, in order to produce a friction-locking connection. A
Σ-shaped formation of the laterally adjacent walls of the chamber is meant to

prevent the bushing from aligning crooked with respect to the wall when the pressure acts on
chamber. The X-shaped side walls of the chamber make possible, in the case of pressure
pressurization, an expansion of these side walls in a radial direction toward the shaft, before the
increasing chamber pressure also presses the chamber wall, running parallel to the shaft, against
the shaft. Thus, the bushing can be aligned at right angles to the shaft axis, before the tortional
connection is produced.
This clamping device does not have a favorable power transmission for the creation of a
higher pressing force. Furthermore, in its shape and in particular., in its placement possibility
relative to the bushing body, the chamber is limited. The braking effect can be attained here only
by acting on the chamber with excess pressure, and the actual braking element, which must
perhaps transfer high driving-forces, is not firmly connected to the bushing body, but rather only
via the inevitably relatively unstable pressure chamber.
From WO 01/34990 A1 from the applicant, a clamping and/or braking device is known,
in which a chamber which can be acted on with pressure is provided on a basic body; in at least
one partial area of at least one deformable or tension-resistant and/or pressure-resistant wall, the
chamber is limited. The limitation of the chamber opposite the wall can also be constructed like
the first wall. However, it can also be a rigid part of a body. Preferably, the walls lie at a
relatively small distance from one another. The forces resulting from the deformation of the
chamber are conducted, at least in part, in the direction of or along the wall and in the area of the
connection of the wall to a basic body are introduced into the lattter. If one selects the point of
attack of such forces on the basic body, and if this basic body is, at least partially, elastically
deformable, then the forces can be transferred, for example, into the clamping or braking areas
via this basic body on other sites of the basic body. A corresponding braking or clamping means
in these areas can then be moved, by means of the forces, into a pressurizing position or out of it,
so as to brake or release a guide element or an element which has to be clamped or braked. Both
applied excess or reduced pressure in the chamber can be used thereby, in order to introduce both
tractive and compressive forces to the basic body. Of course, before and after the introduction of
force, the clamping and/or braking areas are still engaged with the guide element or the element
to be clamped or braked, wherein, however, changes in the pressurizing forces between the
clamping and/or braking areas and the other element result.
This known clamping and/or braking device is based on the knowledge that when acted
on by a reduced or excess pressure, a suitable chamber tends to a deformation. If this chamber, to
a great extent, is formed by at least one approximately plane wall, then the excess or reduced
pressure in the chamber first causes a deformation in a first direction running essentially

Perpendicular to this wall. In order to yield to the deformation (expansion or contraction) in this first
direction, the result from this, in a correspondingly reverse manner, is a contraction or expansion of
the chamber in a second direction generally running perpendicular; to the first direction (that is,
essentially parallel to the wall). The fact is used thereby that low forces or deformations in the first
direction produce large forces in the second direction, which can be used to break or clamp or to
release pretensioned clamping or braking devices.
On the basis of this state of the art, the goal of the invention is to create a clamping and/or
braking device, which can be produced with lower construction expense and with which sufficiently
high braking or clamping forces can be produced in a simple manner.
In contrast to the disclosures of US 3363027 and US 45443887, the present invention
provides a clamping and/or braking device, wherein a plate-shaped element has radial slots
opening inwards, and second end of the element is formed by the inner end of the element, or the
element has radial slots opening outwards, and the second end of the element is formed by the
outer end of the element. Further, at least one sealing element is provided at the inner and/or outer
surfaces in relation to the pressure space of the element, at least in the area of the slots.
Accordingly, the invention provides clamping and/or braking device comprising a housing, in
which at least one ring-shaped, plate-shaped element is held, which element: is supported with a
first end with respect to a stop area of the housing and which with a second end transmits clamping
and/or braking forces to an object or a pressurisable element, which transmits clamping and/or
braking forces to the object, wherein
a) said at least one ring-shaped, plate-shaped element has at least one bending area which is
convex in the initial state and is formed so as to be pressure-resistant and yet elastically bendable
so that the bending area forms a resilient element between the stop area of the housing and a
pressurisable end of the ring-shaped, plate-shaped element,
b) a substantially tight pressure space is formed between the convex side of said at least one
bending area of said at least one ring-shaped, plate-shaped element and the housing, which space
can be acted upon by the excess pressure of a pressure medium which can be supplied to the
housing, and
c) said at least one ring-shaped, plate-shaped element and its at least one bending area are
formed so that, when the pressure space is acted upon by excess pressure, as a result of a
reduction of the curvature of the bending area, in order to obtain predetermined clamping and/or
braking forces, a movement of the second end of said at least one ring-shaped, plate-shaped

element or a movement of the second end of said at least one ring-shaped, plate-shaped element
together with the pressurisable element takes place in the direction of the object or an increase in
the clamping and/or braking forces transmissible to the object by the second end of said at least
one ring-shaped, plate-shaped element or the pressurisable element is brought about,
characterised in that
i) said at least one ring-shaped, plate-shaped element has radial slots
which are open inwards, wherein the second end of the ring-shaped,
plate-shaped element is formed by the inner end of the ring-shaped,
plate-shaped element, or
ii) said at least one ring-shaped, plate-shaped element has radial slots
which are open outwards, wherein the second end of the ring-shaped,
plate-shaped element is formed by the outer end of the ring-shaped,
plate-shaped element, and
iii) one or a plurality of sealing element(s) is/are provided at the inner and /or
outer surfaces, in relation to the pressure space, of said at least one ring-
shaped, plate-shaped element, at least in the area of the slots.
The invention is based on the knowledge that by means of at least one plate-like element,
which is located in a housing and has a convex bending area, a clamping and/or braking device can
be produced at low cost; this device can also produce very high clamping and/or braking forces by
means of an only gaseous pressure medium-that is, pneumatically. However, it is clear that a
hydraulic actuation of the device is also possible. The function of the device is guaranteed by the
convex formation of at least one bending area of the plate-like element, with application on its
convex side of an excess pressure from a pressure medium, wherein a corresponding pressure
space is provided on the side of the bending area, which curves convexly outwards. With pressure
acting on the bending area, its curvature is reduced; so that the expansion of the plate-like element
between two ends is increased, of which one is supported on the housing and the other acts,
directly or indirectly, via a pressurizable element, on the object to be clamped or braked. The plate-
like element is thereby so pressure-resistant and constructed so elastically deformable in the at
least one bending area that between the two ends, an elastic element is formed. The pressure
resistance of the plate-like element must be designed in such a way that when a predetermined,
maximum permissible force is exerted on the second end (pressurizing end), a sharp bending does
not occur.

Of course, a corresponding free space, which makes possible a sufficient
bending of the bending area, must be present on the concave side of the bending area,
turned away from the pressure application side. This free space can be connected to the
surroundings—that is, to the air pressure of the surroundings. However, it can also be
closed airtight so that the bending of the bending area must take place, against an
increasing pressure, in the free space.
Contrary to the known device of the applicant, it is possible, with
these embodiments, to produce or to change clamping and/or braking
forces, without hereby having to deform an essentially rigid body. In this
way, aside from a simple construction, a small model results. The

device is, moreover, simple to produce, since only the plate-like element must be placed in the
housing.
Contrary to the known clamping bushings, which have relatively soft walls, and which
increase the distance between a pressurizable element and a base element when acted on with
excess pressure, it is also possible with the device in accordance with the invention to produce a
predetermined clamping and/or braking force, with which the object to be clamped or braked is
acted on, even in a pressure-less state during a corresponding pretensioned installation of the
device in the complete device. In this way, for example, a control of the device is possible, in
such a way that a change between a braked (in the pressure-less state) movement of the
pressurized object and a complete clamping of the object (with a sufficient pressurization)
results.
The more frequent use of the device in accordance with the invention, however, is the one
where in the pressure-less starting state, the object is not acted on and with a pressurization of the
device, is braked or clamped.
With a linearly functioning clamping and/or braking device, the at least one plate-like
element can have a, for example, rectangular shape, wherein the entire element can be convexly
curved between two edges. The first and the second ends are then formed by those edges or end
areas between which the curvature runs. At least in the area of the bending (if the entire plate-
shaped element is not bent), the side edges must be essentially sealed off with respect to the
housing (a small leakage can be tolerated, under certain circumstances, if, for example,
compressed air is used as the pressure medium and the required pressure can be attained and
maintained in spite of the leakage)
According to one development of the invention, a pressurizable element is provided,
which is constructed in one piece with the housing and as a pant of the housing, or which is
constructed as a part connected to the housing in a detachable manner, wherein the pressurizable
element is constructed deformably in such a way that with a pressure application of the pressure
space, a movement of at least one section of the pressurizable element takes place in the direction
of the object or the transferable clamping and/or braking forces, produced by the at least one
plate-like element, are transferred to the object. With such a deformable pressurizable element,
the pressure space can be sealed of in a simple manner, with respect to the at least one plate-like
element—namely on the pressurizing edge or the second end of the plate-like element, with
respect to the pressurizable element. Basically, however, a pressurizable element is not connected
to the housing can also be used, which, for example, can be constructed correspondingly large for
the distribution of the pressing force on a greater surface. Moreover, the pressurizable element

can be used to adapt the pressing surface (constructed then on the pressurizable element) to the
shape of the object.
In a development of the invention, the first end of the at least one plate-like element can
be connected to the housing, especially if in the realization of a linearly acting clamping and/or
braking device, a pressurizable element not connected to the housing is used or the object is
acted on directly by the second end of the at least one plate-like element.
In the preferred embodiment of the invention, the first end of the at least one plate-like
part, however, is supported, without a firm connection, against the housing. With the presence of
a pressurizable element, the second end of the at least one plate-like part is also preferably
supported, without a firm connection, against the pressurizable element. In this way, a simple
installation of the device results.
According to one embodiment of the invention, the at least one-plate-shaped element is
annular, preferably, circular, so as to create a device that makes possible the clamping of bar- or
rod-shaped objects, in particular, in the cross section of circular-cylindrical objects.
The ring-shaped, plate-like element can be shaped convexly, in the starting state, via
essentially the entire radial cross section, wherein essentially the entire ring-shaped wall of the
ring-shaped, plate-like element serves as the bending area Such a plate-like element can be
produced very simply and at low cost and can be used also for a large number of variants.
The at least one ring-shaped, plate-like element preferably has radial slits that are open
inwardly or outwardly, wherein, preferably, the second end-that is, the pressurizing end of the
ring-shaped, plate-like element—is formed by the inside or outside end of the ring-shaped, plate-
like element. The slits preferably extend to just before the opposite end of the ring and are
present in such a number that proceeding from the closed ring area, individual sections extend
inwardly or outwardly. These sections reduce the required deformation of the ring in the azimuth
direction, if the curvature of the convex bending area is reduced during pressurization.
With such slit, ring-shaped, plate-like elements, it is possible to provide one or more
sealing elements, preferably, in the shape of a deformable layer, on a part or on the entire surface
of the plate-like element, on the inside and/or outside surfaces of the plate-like elements, relative
to the pressure space, at least in the area of the slits. In this way, a common pressure space can be
used for the individual sections between the slits. The sealing of the slits can, for example, take
place by vulcanizing on a relatively hard, but nevertheless, sufficiently deformable rubber layer.
Such a layer can be produced even on the side of the ring-shaped, plate-like element, turned away
from the pressurization, without the danger of loosening the layer during a pressurization.
In the preferred embodiment of the invention, the bending of the at least one bending area

of the at least one plate-like element is limited in such a way that after the discontinuation of the
pressurizing of the pressure space with excess pressure as a result of the elastic effect of the at
least one bending area, it returns to the starting state. One designates, as the starting state, the
pressure-less state, wherein in this state also, depending on the dimensioning or installation of
the clamping and/or braking device, the at least one bending area can be pretensioned. A
corresponding stop for the bending area can be formed, for example, by an inside housing wall.
According to one development of the invention, several plate-like elements, arranged
essentially parallel to one another, can be provided, whose second ends have a predetermined
distance to one another, in order to transfer clamping and/or braking forces to the object, via a
prespecified expanded area, wherein for each plate-like element, a separate pressure space or for
several or all plate-like elements, a common pressure space can be formed.
When using several plate-like elements, at least one pair of plate-like elements can be
provided, whose first and second ends are directly adjacent or at a close distance to one another,
and whose convex bending areas run convexly outwards, relative to the other plate-like element
of the pair of plate-like elements, wherein a common pressure space is provided for the
pressurization of the bending areas of the two plate-like elements of a pair. This variant offers the
advantage that the two plate-like elements are pressed against one another during a pressurization
and so the space required between the two elements can be sealed off with lower pressure in a
simple manner. For example, the rubber coating mentioned in the preceding can be provided
inside or can be a sealing element connected to the inside surfaces of the plate-like elements.
In addition, the plate-like elements of a pair can be designed in such a way that they lie
close to one another, with at least one partial area of the sides facing one another in an ending
state when acted on with an excess pressure greater or equal to a prespecified maximum pressure,
wherein the ending state is defined by a suitable formation of the bending areas in such a way
that from the ending state, an automatic return to the pressure-less starting state takes place. In
this way, a plate-like element is used as a stop for the at least one bending area of the other plate-
like element.
According to one embodiment of the invention, a pressurizable element can be provided,
which is constructed rigid in the entire area in which the several plate-like elements are active. In
this way, a more uniform transfer of the clamping and/or braking forces can be attained on the
object.
With all embodiments of the invention, the creation of the clamping and/or braking
forces, however, takes place exclusively or at least, for the most part, predominantly due to one
pressurization and the bending hereby produced and thus the change of the effective expansion of

the plate-like elements between the two ends. This is also true for the case that one
surface of the pressurizable element is acted on completely or partially with pressure, if
the bending area(s) of the plate-like elements are acted on with pressure. The forces
hereby produced, which are comparable with the forces arising with common clamping
bushings, can be practically neglected however.
In another embodiment of the invention, the housing and the pressurizable
element can be designed as essentially H-shaped bodies, wherein the at least one
plate-like element and the pressure space are provided between the essentially parallel,
upper legs of the H-shaped body, wherein clamping and/or braking areas are provided
on the essentially parallel, lower legs of the H-shaped body for the transfer of the
clamping and/or braking forces to the object and wherein the H-shaped body is
elastically deformable in the area of the middle crosslink and/or the connecting areas of
the middle crosslink with the legs of the H.
In a similar manner, the housing and the pressurizable element can be designed
as essentially U-shaped bodies, wherein the at least one plate-like element and the
pressure space are provided between the essentially parallel legs of the U-shaped body,
wherein clamping and/or braking areas are provided on the essentially parallel legs of
the H-shaped body for the transfer of the clamping and/or braking forces on the object
and wherein the U-shaped body is elastically deformable in the area of the base of the U
and/or in the area of the legs of the U.
Other embodiments of the invention can be deduced from the preferred
embodiments described hereinafter.
The invention is explained in more detail below, with the aid of the embodiment
examples shown in the accompanying drawing, wherein -
Figure 1, a longitudinal section (Fig. 1a) and a detail enlargement (Fig. 1b) of a
first embodiment of a clamping and/or braking device, according to the invention, for the
pressurizing of a circular-cylindrical object, using a ring-shaped, plate-like element;
Figure 2, a top view (Fig. 2a) of the ring-shaped, plate-like element in Figure 1
and a detail enlargement (Fig. 2b) in sectional view along the line A-A in (Fig. 2a) ;
Figure 3, a longitudinal section (Fig. 3a) and a detail enlargement (Fig. 3b) of a
second embodiment of a clamping and/or braking device according to the invention for
the pressurization of a circular-cylindrical object, using several pairs of ring-shaped,
plate-like elements ;

Figure 4, a detail enlargement of a third embodiment of a clamping and/or braking
device according to the invention, analogous Figure 3, but using a ring-shaped
pressurizable element;
Figure 5, a detail enlargement of a fourth embodiment of a clamping and/or
braking device according to the invention, analogous Figure 4, but using a pressurizable
element,

constructed as one piece with the housing; and
Figure 6, a schematic cross section through a fifth embodiment of a clamping and/or
braking device according to the invention for the realization of a linear guide.
The embodiment of a clamping and/or braking device 1, shown in Figure 1 in a schematic
longitudinal section, has a ring-shaped housing 3, which consists of a first part 5 with a ring-
shaped recess 7 and a second part 9, which is connected to the first part 5, for example, screwed
to it. In the recess 7, between the first and second housing part 5, 9, a ring-shaped, plate-like
element 11 is located. The ring-shaped, plate-like element 11 is shaped slightly convex in the
radial section and applies pressure on the circumferential wall of the ring-shaped recess 7 of the
first housing part 5 with its outside end or its outside boundary 1 la
As can be seen from Figure lb, the ring-shaped, plate-like element 11, consisting, for
example, of a steel sheet, can be connected, on one side, to a sealing element 13, for example, a
relatively hard, but still sufficiently deformable rubber ring. The ring-shaped, plate-like element
11 is, as shown in Figures 2a and 2b, provided with a large number of slits 14, which proceeding
from an outside boundary area 11c, which is also closed in the shape of a ring, run radially
inwards and open toward the inside.
The ring-shaped, plate-like element 11 defines, together with the sealing element 13, on
its convex side, together with the inside wall of the first housing part 7, a pressure space 15, to
which a pressure medium can be supplied, for example, compressed air. Of course, however, a
liquid pressure medium can also be used. The pressure space 15 is constructed open toward the
inside in the embodiment shown in Figure 1 and must be sealed off, with respect to the object 17
to be acted on, for example, a rotatable shaft. This can take place by means of corresponding
sealing elements 19, which can be designed as O rings. The O rings 19 can be taken up in
grooves in the inside walls of the first and second housing part 5, 9.
The ring-shaped, plate-like element 11 lies close to the inside wall of the second housing
part 9 in the embodiment example shown in Figure 1, with its outside and inside boundaries 11a,
11b, wherein the sealing element sufficiently seals off the space between the concave surface of
the element 11 and the inside wall of the housing part 9. In this respect, an annular area 13a, 13b
of the sealing element can be constructed on the outside and inside boundary. The inside annular
area 13b can be designed so far, in its radial expansion, that it lies close to the inside wall of the
housing part 9, at least with a partial area over the entire movement path of the element 11. The
space between the concave side of the element 11 and the housing part 9 can also be connected to
the surroundings, via one or more (not depicted) canals.
If the pressure medium is conducted under a certain pressure to the pressure space 15, via

one or more (not depicted) supply canals, then the ring-shaped, plate-like element 11 is
bent in the direction of the second housing part 9-that is, the curvature is reduced. In
this way, the sections of the element 11, stretching inwards between the slits 14, are
moved, with its inside boundary 11b, further inwards in the direction of the object 17, so
that a desired braking or clamping force can be exerted on the object by a certain
pressure of the pressure medium. The element 11 must, of course, be so dimensioned
and be made of such a material that at least in one bending area, there is a sufficient
deformability and moreover, the element 11 is constructed sufficiently pressure-resistant
as a whole that even with the maximum producible clamping or braking force, which
acts on the inside end of the element 11 or is exerted on the object 17 by it, no sharp
bending of the element 11 or even a plastic deformation occur.
The inside wall of the second housing part 9 is also used as a stop for the ring-
shaped, plate-like element 11, so that even with high pressures, an abrupt reverting of
the convex curvature to a concave curvature cannot occur. Moreover, the inside wall of
the second housing part 9 and/or the ring-shaped, plate-like element 1 or the sealing
element 13 can be constructed in such a way that the cuivature of the element 11 is
reduced, as a maximum, so much that with a subsiding of the pressure, the elastic
effect of the element 11 ensure that the element 11 again returns to the curvature
present in the pressure-less starting state. In this respect, the inside wall of the housing
part 9 can be constructed, for example, slightly convex in the direction of the element 11
or one or more stop elements can be provided on the inside wall of the housing part 9 or
on the element 11 or on the sealing element 13.
At this point, it should be noted that the sealing element can, of course, also be
provided on the outside convex side of the element 11. In this case, it is also possible to
use a loose sealing element, not connected to the element 11, for example, a separate,
ring-shaped sealing disk made of rubber or plastic.
The embodiment of a clamping and/or braking device shown in Figure 3 is
similar to the embodiment in Figure 1. Instead of a single ring-shaped, plate-like
element 11, five pairs of ring-shaped, plate-like elements 11, as a whole, are, however,
provided in this embodiment. In this way, ten times the braking or clamping forces can
be transferred to the object 17 with the same pressure of the pressure medium.

The two ring-shaped, plate-like elements 11 of a pair are placed thereby
in such a way that their concave sides oppose each other. In this way, a
space sealed-off with respect to the pressure space 15, in which the
elements 11 of the pairs of elements, sealed off with respect to each other, is formed, in
a simple manner, between each pair of elements 11. With a pressurization of the
pressure space 15 with the pressure of the pressure medium, the slit walls of

the elements 11 are there to be bent toward one another. Since the inside ends 1 lb of the
elements 11 of a pair move jointly, a sealing off of the space between the elements 1 can be
reliably attained with simple means. The outside boundaries of the elements 11 can, of course,
also be held, for the fixing, by suitable means in the housing 3, for example, in grooves in the
circumferential wall of the cylindrical recess 7 of the first housing part 5. The two elements 11 of
a pair can, of course, also be connected to one another-for example, they can be locked together.
The embodiment of a clamping and/or braking device 1, according to Figure 4, differs
from the embodiment shown in Figure 3 merely in that the inside ends 1 lb of the elements 11 do
not apply pressure directly on the object 17 to be braked or to be clamped, but rather, via a ring-
shaped pressurizable element 21, which is located inside the housing 3. The pressurizable
element 21 is so deformed by the forces exerted by the pairs of ring-shaped, plate-like elements
11 —in particular, the inside diameter of the pressurizable element 21 is reduced to such an extent
that the forces are transferred, at least partially, to the object 17.
This embodiment offers the advantage that the sealing off of the pressure space 15
between the housing and the pressurizable element 21 can take place—for example, again via the
sealing elements 19 in the form of O rings.
As can be seen from Figure 5, in which another embodiment of a clamping and/or
braking device is shown, it is also possible to provide a pressurizable element 21, constructed in
an integrated manner with the housing 3, instead of a separate pressurizable element. In the case
shown, the recess 7 in the first housing part 5 is designed in such a manner that a thin inside wall
is formed, which forms the pressurizable element 21. The wall must be so thin that a sufficient
deformation can be guaranteed when forces are exerted by the pairs of ring-shaped, plate-like
elements 11 and thus a sufficient transfer of these forces to the object 17. The sealing off of the
pressure space 15 can take place here in that the thin wall or the pressurizable element 21 is
connected to the second housing part 9 in an essentially airtight manner. For the sealing, a sealing
element 19, for example, in the form of an O ring, can again be used.
Of course, such a clamping and/or braking device can also be designed in such a way that
the corresponding forces are transferred to an object on a point-like, linear, or non-ring-shaped
closed surface, for example, for the production of a clamping and/or braking device for a linear
guide.
If one does not interpret the representation in Figure 5 as an excerpt from an essentially
rotation-symmetrical representation, but rather as an excerpt from a representation with a (for
example, rectangular) housing 3, in which rectangular, plate-like elements 11 are placed, then a
clamping and/or braking device is formed for the pressurization of the surface of an object 17, in

which, for example, it may be a track of a linear guide. The housing 3 can, for example, be
mounted on a carriage, not depicted in more detail, conducted by means of the object 17 designed
as a track. The carriage can grip the track so that the exertion even of high forces on the surface
of the object is possible, without lifting the carriage off the track. The mode of functioning of, for
example, rectangular, plate-like elements can be deduced analogous to the preceding statements
in connection with the annular, plate-like elements.
If a pressurizable element 21 is not used with such an embodiment, then the plate-like
elements 1 can be held, with their inside ends 1 la, in the housing or connected firmly with it (one
piece or detachable). Of course, a sealing off of the pressure space 15, with respect to the object
17, must then again take place. The lateral edges or areas of the rectangular, plate-like elements
must also be sealed off to create a pressure space or a "pressure-less" space between the pairs of
plate-like elements.
The embodiment according to Figure 6 is also a version of a clamping and/or braking
device 1, with which a linear guide can be realized. The first housing part 5 is constructed, in this
case, with an H-shaped cross section, wherein between the upper legs of the H, a pair of, for
example, rectangular, plate-like elements 11 is provided. Since such elements 11 need not be
provided with slits, it is possible, of course, to also dispense with corresponding sealing
elements. The pressure space 15 is, in turn, formed outside the pair of the plate-like elements 11.
In a pressurization of the pressure space 15, a deformation of the H-shaped housing part 5
is produced, in particular, in the area of the middle crosslink of the H and the transition areas
between the crosslink and the lateral legs of the H. In this way, the rigidly constructed, lower legs
of the H are moved inwards in the direction of the intermediately placed object 17 and transfer
corresponding braking or clamping forces to the object. In this respect, it is possible to provide
clamping and/or brake shoes 23 on the insides of the lower legs of the H.
If instead of an H-shaped housing part 5, a U-shaped housing is used, in which one or
more (for example, rectangular) plate-like elements, are provided between the legs of the U, with
these elements pressing the legs of the U toward the outside with a pressurization, then an "active
loosening" of an object, for example, with a linear guide, can be realized. Of course, this can also
be attained with an H-shaped housing in that the brake shoes are located on the outsides of the
lower legs of the H and they apply pressure on the object, for example, in a groove. Conversely,
an "active clamping or braking" can also be produced with a U-shaped housing, if the brake
shoes are located on the outsides of the legs of the U and correspondingly apply pressure on the
object.
Finally, it should be pointed out that of course, individual features which are described in

the preceding only in connection with a specific embodiment can also be combined, if
reasonable, with other embodiments also.

I CLAIM :
1. Clamping and/or braking device comprising a housing, in which at least one
ring-shaped, plate-shaped element is held, which element is supported with a first end
with respect to a stop area of the housing and which with a second end transmits
clamping and/or braking forces to an object or a pressurisable element, which transmits
clamping and/or braking forces to the object, wherein
a) said at least one ring-shaped, plate-shaped element has at least one bending
area which is convex in the initial state and is formed so as to be pressure-resistant and
yet elastically bendable so that the bending area forms a resilient element between the
stop area of the housing and a pressurisable end of the ring-shaped, plate-shaped
element,
b) a substantially tight pressure space is formed between the convex side of said at
least one bending area of said at least one ring-shaped, plate-shaped element and the
housing, which space can be acted upon by the excess pressure of a pressure medium
which can be supplied to the housing, and
c) said at least one ring-shaped, plate-shaped element and its at least one bending
area are formed so that, when the pressure space is acted upon by excess pressure, as
a result of a reduction of the curvature of the bending area, in order to obtain
predetermined clamping and/or braking forces, a movement of the second end of said
at least one ring-shaped, plate-shaped element or a movement of the second end of
said at least one ring-shaped, plate-shaped element together with the pressurisable
element takes place in the direction of the object or an increase in the clamping and/or
braking forces transmissible to the object by the second end of said at least one ring-
shaped, plate-shaped element or the pressurisable element is brought about,
characterised in that
i) said at least one ring-shaped, plate-shaped element has radial slots
which are open inwards, wherein the second end of the ring-shaped,
plate-shaped element is formed by the inner end of the ring-shaped,
plate-shaped element, or
ii) said at least one ring-shaped, plate-shaped element has radial slots
which are open outwards, wherein the second end of the ring-shaped,
plate-shaped element is formed by the outer end of the ring-shaped,
plate-shaped element, and

iii) one or a plurality of sealing element(s) is/are provided at the inner and /or
outer surfaces, in relation to the pressure space, of said at least one ring-
shaped, plate-shaped element, at least in the area of the slots.
2. Device as claimed in Claim 1, wherein the ring-shaped, plate-shaped element
acts on a pressurisable element, which is formed in one piece with the housing and as
part of the housing or as a part connected to the housing in a detachable manner, the
pressurisable element being formed in a flexible manner such that, when the pressure
space is pressurised, a movement at least of one portion of the pressurisable element
takes place in the direction of the object or the transmissible clamping and/or braking
forces produced by said at least one ring-shaped, plate-shaped element are transmitted
to the object.
3. Device as claimed in Claim 1 or 2, wherein the first end of the at least one ring-
shaped, plate-shaped element is connected to the housing.
4. Device as claimed in any one of the preceding Claims, wherein the first end of
said at least one ring-shaped, plate-shaped element is supported without a firm
connection against the housing and, with the presence of a pressurisable element, the
second end of said at least one ring-shaped, plate-shaped element is preferably also
supported without a firm connection against the pressurisable element.
5. Device as claimed in any one of the preceding Claims, wherein said at least one
ring-shaped, plate-shaped element is formed in the shape of a circular ring.
6. Device as claimed in any one of the preceding Claims, wherein the ring-shaped,
plate-shaped element is formed so as to be convex over substantially the entire radial
cross section in the initial state, substantially the entire ring-shaped wall of the ring-
shaped, plate-shaped element serving as a bending area.
7. Device as claimed in any one of the preceding Claims, wherein said one or said
plurality of sealing element(s) is/are provided in the form of a flexible layer on a part or
on the entire surface of the ring-shaped, plate-shaped element.

8. Device as claimed in any one of the preceding Claims, wherein the bending of
said at least one bending area of said at least one ring-shaped, plate-shaped element is
limited such that, after discontinuation of the action on the pressure space by excess
pressure, as a result of the resilient action of said at least one bending area, this is
moved back into the initial state.
9. Device as claimed in any one of the preceding Claims, wherein a plurality of ring-
shaped, plate-shaped elements are provided, the second ends of which elements have
a predetermined spacing in order to transmit clamping and/or braking forces to the
object over a predetermined extensive area ; and a separate pressure space is formed
for each ring-shaped, plate-shaped element or a common pressure space is formed for
a respective plurality of or all ring-shaped, plate-shaped elements.
10. Device as claimed in any one of the preceding Claims, wherein at least one pair
of ring-shaped, plate-shaped elements is provided, the first and second ends of which
are directly adjacent or at a close spacing from one another and the convex bending
areas of which in each case extend convexly outwards, relative to the respective other
ring-shaped, plate-shaped element of the pair ; and a common pressure space is
provided for acting on the bending areas of the two ring-shaped, plate-shaped elements
of a pair.
11. Device as claimed in Claim 10, wherein the ring-shaped, plate-shaped elements
are formed so that, in a final state, when they are acted upon by an excess pressure
which is greater than or equal to a predetermined maximum pressure, they lie against
one another with at least a partial area of the facing sides, wherein the final state is
defined by a suitable formation of the bending areas so that an automatic return from
the final state to the pressureless initial state takes place.
12. Device as claimed in any one of Claims 9 to 11, wherein a pressurisable element
is provided which is formed so as to be rigid in the entire area in which the plurality of
ring-shaped, plate-shaped elements act.

The invention concerns a clamping and/or braking device with a housing, in which at
least one plate-like element is held, which is supported, with a first end, opposite a stop area of
the housing and which, with a second end, transfers clamping and/or braking forces to an object,
or acts on a pressurizable element, which transfers clamping and/or braking forces to an object,
wherein the plate-like element has at least one bending area which is convex in the starting state,
which is constructed pressure-resistant and nevertheless elastically deformable so that the
bending area forms an elastic element between the stop area of the housing and a pressurizing
end of the plate-like element, wherein an essentially airtight pressure space is formed between
the convex side of the at least one bending area of the at least one plate-like element and the
housing, wherein the pressure space can be acted on with the excess pressure of a pressure
medium which can be supplied to the housing, and wherein the at least one plate-like element
and its at least one bending area are constructed in such a way that with an pressurization of the
pressure space with excess pressure, as a result of a reduction of the curvature of the bending area
to attain prespecified clamping and/or braking forces, a movement of the second end of the at
least one pressurizable element (17) takes place in the direction of the base element (7), or an
increase of the clamping and/or braking forces, which can be transferred to the object by the
second end of the at least one pressurizable element, is brought about.

Documents:

308-KOLNP-2006-(03-01-2012)-FORM-27.pdf

308-KOLNP-2006-CORRESPONDENCE.pdf

308-KOLNP-2006-FORM 27.pdf

308-kolnp-2006-granted-abstract.pdf

308-kolnp-2006-granted-claims.pdf

308-kolnp-2006-granted-correspondence.pdf

308-kolnp-2006-granted-description (complete).pdf

308-kolnp-2006-granted-drawings.pdf

308-kolnp-2006-granted-examination report.pdf

308-kolnp-2006-granted-form 1.pdf

308-kolnp-2006-granted-form 18.pdf

308-kolnp-2006-granted-form 3.pdf

308-kolnp-2006-granted-form 5.pdf

308-kolnp-2006-granted-gpa.pdf

308-kolnp-2006-granted-reply to examination report.pdf

308-kolnp-2006-granted-specification.pdf

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Patent Number

226763

Indian Patent Application Number

308/KOLNP/2006

PG Journal Number

52/2008

Publication Date

26-Dec-2008

Grant Date

24-Dec-2008

Date of Filing

13-Feb-2006

Name of Patentee

HOFMANN KLAUS

Applicant Address

BIRKENWEG 10, 85567 BRUCK

Inventors:

#	Inventor's Name	Inventor's Address
1	HOFMANN KLAUS	BIRKENWEG 10, 85567 BRUCK

PCT International Classification Number

F16D 65/14, 63/00

PCT International Application Number

PCT/DE2004/001712

PCT International Filing date

2004-07-30

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	103 35 795.5	2003-08-05	Germany