Title of Invention	"APPARATUS FOR AUTOMATICALLY ACTUATING THE NEEDLES OF A JACQUARD MECHANISM"
Abstract	The above comprises a plurality of parallel plates (2) spaced apart at a pitch e that is identical to the pitch of successive rows of needles. In the space between two successive plates (2) there are mounted both selector members (7) associated with the needles (1)- of a given row, which selector members are movable in a common plane parallel to the planes of the plates (2) and, 'for each selector member (7), a two-portion electromagnetic circuit enabling at least one electromagnetic field (Cl) to be induced transversely to the planes of the plates (2), the two portions of the electromagnetic circuit being mounted on the facing faces (2a, 2b) of two successive plates. Each selector member (7) includes a magnetized proton located between the two portions of the associated electromagnetic circuit, thereby enabling displacement thereof to be controlled.

Title of Invention

"APPARATUS FOR AUTOMATICALLY ACTUATING THE NEEDLES OF A JACQUARD MECHANISM"

Abstract

The above comprises a plurality of parallel plates (2) spaced apart at a pitch e that is identical to the pitch of successive rows of needles. In the space between two successive plates (2) there are mounted both selector members (7) associated with the needles (1)- of a given row, which selector members are movable in a common plane parallel to the planes of the plates (2) and, 'for each selector member (7), a two-portion electromagnetic circuit enabling at least one electromagnetic field (Cl) to be induced transversely to the planes of the plates (2), the two portions of the electromagnetic circuit being mounted on the facing faces (2a, 2b) of two successive plates. Each selector member (7) includes a magnetized proton located between the two portions of the associated electromagnetic circuit, thereby enabling displacement thereof to be controlled.

Full Text	The present invention relates to an apparatus for automatically actuating the needles of a Jacquard mechanism. The present invention relates to electromagnetic apparatus for automatically actuating the needles of a Jacquard mechanism, and also to a Jacquard mechanism fitted with such an apparatus. More precisely, it relates to apparatus designed to be moved relative to the needles of a Jacquard mechanism in order to push them selectively under the control of electromagnetic means to make a selection that is established automatically on each cycle of the Jacquard mechanism. More particularly, but non-exclusively, the invention serves to replace the punched cards of Jacquard mechanisms used for controlling lacemaking machines, and in particular Leavers' lacemaking machines. Proposals have already been made, in particular in European patent EP-A-0 382 998, to replace the traditional punched cards of a Jacquard.mechanism by an electromagnetic control apparatus for pushing the needles of the Jacquard mechanism selectively. That document teaches controlling the selection of each needle of the Jacquard mechanism automatically by means of a solenoid, and more particularly a two-position solenoid having two concentric windings referred to respectively as an ( "engagement" winding and as a "release" winding.-Electrically powering the release winding causes a selection member in the form of a rod to be extended, while electrically powering the engagement winding enables said selection rod to be retracted. The apparatus is also fitted with means enabling it to be moved relative to the needles of the Jacquard mechanism. In a first variant embodiment, shown in particular in Figure 1 of that document, the selection rod of each solenoid is associated with a passage, and has the function of closing the passage when brought into its extended position. When the apparatus comes into contact with the needles of the Jacquard mechanism, all of the needles that are in register with respective passages that are closed by selection rods are pushed by the apparatus as it moves. In contrast, the needles of the Jacquard mechanism situated in register with passages that are not closed by respective selection rods penetrate into said passages during displacement of the apparatus and are therefore not pushed by the apparatus. In a second variant embodiment shown in Figure 4 of that document, the selection rods act on respective intermediate pushers, and serve to lock the pushers in the extended position. When a pusher is locked in the extended position, it enables the corresponding needle of the Jacquard mechanism to be pushed during displacement of the apparatus. When a pusher is not locked in the extended position, it is returned elastically by a return spring to a retracted position and it cannot come into contact with the associated needle. The electromagnetic apparatuses described in European patent application EP-A-0 382 998 serve advantageously firstly to enable the needles of a Jacquard mechanism that need to be pushed during a given cycle to be selected automatically by appropriately controlling the electrical power supply to the windings of each solenoid associated with a needle, and secondly to enable very little energy to be used to control each solenoid. Nevertheless, the solenoids described in that document suffer from the drawback of being bulky, and as a result they are unsuitable for being adapted to select the needles of a Jacquard mechanism disposed in successive rows with small spacing between rows, and in particular a spacing of less than 1 cm. An object of the present invention is to propose an electromagnetic apparatus that presents the advantages of the apparatuses of the above-mentioned European patent application, but made up of electromagnetic selector members that are more compact, thereby enabling it to be adapted to controlling the needles of a Jacquard mechanism organized as successive close-together rows. More particularly, the apparatus of the invention is suitable for Jacquard mechanisms used for controlling Leavers' lacemaking machines in which the spacing between two successive rows of needles is very small, being of the order of 6 mm. Nevertheless, the invention is not limited to that particular type of Jacquard mechanism, but can be applied in general manner to any type of Jacquard mechanism controlled by needles that need to be pushed in selective manner and that are disposed in successive rows. The mechanism may be constituted, in particular, by Jacquard mechanisms having cords or hooks for controlling textile machinery, and in particular looms. The Jacquard mechanism may also be of the type described in French patent application FR-A-2 704 562 in which the needles that need to be pushed, referred to as dropper needles, control the displacement of flexible needles referred to as strikers that are disposed transversely to the drop needles. Finally, the needles of the Jacquard mechanism that need to be pushed in selective manner by the apparatus of the invention may be disposed vertically or horizontally. In the same manner as the apparatuses described in European patent application EP-A-0 382 998, the apparatus of the invention is designed firstly to be moved during each cycle of the Jacquard mechanism relative to the needles in order to push them individually in selective manner, and secondly to implement, for each needle, a selector member which is movable in a direction transverse to the thrust direction of the apparatus between a selection, first position and a retracted, second position, with displacement thereof between the selection and retraction positions being under electromagnetic control in such a manner that when the apparatus is moved it pushes only those needles of the Jacquard mechanism which are associated with a selector member in the selection position. In a manner characteristic of the invention, with the needles of the Jacquard mechanism being disposed in successive parallel rows, the apparatus comprises a plurality of parallel plates spaced apart at a pitch e identical to that of two successive rows of needles; the spaces between successive pairs of plates have mounted therein the selector members associated with the needles of a given row, which selector members are movable in a common plane parallel to that of the plates, and a two-portion electromagnetic circuit is provided for each selector member serving to create at least one induced electromagnetic field extending transversely to the planes of the plates, the two portions of the electromagnetic circuit being mounted respectively on the facing faces of two successive plates and respectively constituting a coil-carrying main portion having at least two opposite electromagnetic pole pieces, and a closure yoke for closing the electromagnetic field and disposed facing the coil-carrying main portion; and each selector member includes a magnetized portion which is positioned between the two portions of the associated electromagnetic circuit so as to enable displacement of the selector member to be controlled. In the context of the invention, each plate could be fitted on each of its two faces either solely with coil-carrying portions, or else solely with closure yokes for closing the electromagnetic field. In which case, plates having coil-carrying portions and plates having closure yokes are placed in alternation. In another variant embodiment, the plates of the apparatus of the invention are all of the same type, and each plate has the coil-carrying portions of the electromagnetic circuits on one of its faces and the closure yokes on its other face for the purpose of closing the respective electromagnetic fields induced by the coil-carrying portions of the adjacent plate. This variant has the advantage of reducing manufacturing costs since all of the plates areidentical. In the context of this variant, the coil-carrying portions and the closure yokes of a plate may be separate, e.g. being stuck to the two respective faces of the plate. However, in order to simplify manufacture of the plates, and thereby further reducing the cost of manufacturing them, it is preferable for each closure yoke of a plate to be constituted by the base of a ferromagnetic mount whose portion remote from the base carries a coil, and which is fixed through the plate such that the base and the coil-carrying portion of the mount are to be found on respective sides of the plate. Preferably, the apparatus includes a separate pusher movable relative to the plates in the plane of the plates and in a direction extending transversely to the displacement axis of the selector members, and capable of being locked in an extended position relative to the plates by the associated selector member, in which position the pusher can push the associated needle of the Jacquard mechanism during displacement of the apparatus. It is necessary for each pusher to be capable of being placed in the extended position relative to the plates and to the selector members by any appropriate means in order to be locked in said position, where appropriate. In a first variant, this can be achieved by moving the assembly formed by the parallel plates and the selector members relative to the pushers. In this first variant, the apparatus includes a reset plate and the assembly constituted by the parallel plates and the selector members is movable in translation relative to the reset plate along the axes of the pushers between a first position in which the set of pushers is in contact with the reset plate and in the extended position, and a second position in which only those pushers which are locked in the extended position relative to the plates are brought into contact with the corresponding needles of the Jacquard mechanism, the pushers that are not locked in the extended position not being entrained and remaining in contact with the reset plate. The relatively large inertia of the assembly formed by the parallel plates and the selector members limits the frequency and/or the amplitude of the motion that can be imparted thereto. In order to mitigate this drawback, a second variant the apparatus of the invention includes a reset plate which is movable in translation relative to the plates and to the selector members along the axes of the pushers and which serves during each cycle of the Jacquard mechanism to bring the pushers into the extended position relative to the plates and to hold them there while displacement of the selector members is being controlled. More generally, the reset plate of the invention can be used in any apparatus enabling the needles of a Jacquard mechanism to be pushed automatically and selectively by means of pushers that can be locked in an extended position by selector members. This additional characteristic of the invention is thus independent of implementing the main means of the invention, i.e. the particular structure as a plurality of parallel plates with, in each space between plates, a plurality of electromagnetic circuits in two portions, each enabling at least one electromagnetic field to be induced transversely to the plane of the plates for the purpose of controlling the displacement of each needle selector member in a given row. In particular, the reset plate of the invention could be fitted to the variant of Figure 4 of European patent application EP-A-0 382 998. According to the present invention there is provided an apparatus for automatically actuating the needles of a Jacquard mechanism, which apparatus is designed firstly to be moved during each cycle of the Jacquard mechanism relative to the needles in order to push them individually in selective manner, and secondly to implement, for each needle, a selector member which is movable in a direction transverse to the thrust direction of the apparatus between a selection, first position and a retracted, second position, with displacement thereof between the selection and retraction positions being under electromagnetic control in such a manner that when the apparatus is moved it pushes only those needles of the Jacquard mechanism which are associated with a selector member in the selection position, the apparatus being characterized in that with the needles of the Jacquard mechanism being disposed in successive parallel rows, it comprises a plurality of parallel plates spaced apart at a pitch e identical to that ui' two successive rows of needles, in that the spaces between successive pairs of plates have mounted therein the selector members associated with the needles of a given row, which selector members are movable in a common plane parallel to that of the plates, and a two- portion electromagnetic circuit is provided for each selector member serving to create at least one induced electromagnetic field extending transversely to the planes of the plates, the two portions of the electromagnetic circuit being mounted respectively on the facing faces of two successive plates and respectively constituting a coil-carrying main portion having at least two opposite electromagnetic pole pieces, and a closure yoke for closing the electromagnetic field and disposed facing the coil carrying main portion, and in that each selector member comprises a magnetized portion which is positioed between the two portions of the associated electromagnetic circuit so as to enable displacement of the selector member to be controlled. Other characteristics and advantages of the invention appear more clearly on reading the description below of a preferred embodiment of the invention, which description is given by way of non-limiting example and is made with reference to the accompanying drawing, in which: • Figure 1 is a fragmentary plan view of apparatus of the invention for automatically selecting dropper needles of a Jacquard mechanism, which needles are disposed in parallel rows with eight needles per row; • Figure 2 is a section view in a vertical plane of the Figure 1 apparatus between two successive plates; and • Figure 3 is a detail section view on a horizontal plane through the apparatus of Figure 1, showing a selector member between two successive plates. The apparatus of Figures 1 to 3 is designed to be mounted to a Jacquard mechanism (not shown) having dropper needles 1, more commonly known as "droppers", of the kind used for controlling a Leavers' lacemaking machine. It replaces the rotary cylinder serving as a support 4 and serving to drive the chain of punched cards traditionally used for selectively pushing the needles of the Jacquard mechanism. In the particular example described below, the needles 1 of the Jacquard mechanism are disposed in a plurality of successive rows that are spaced apart at a constant pitch e, with each row having eight needles. With reference to Figures 1 and 2, the apparatus comprises a plurality of identical parallel plates 2 which are regularly spaced apart at a pitch e identical to that of the rows of needles in the Jacquard mechanism, and which are secured to a pierced guide plate 3. In the particular example shown, with the apparatus being designed to push the vertically dropping needles 1 of a Jacquard mechanism, the plates 2 are vertical while the pierced guide plate 3 is horizontal. More generally, the pierced card plate 3 lies in a plane extending transversely relative to the needles 1 of the Jacquard mechanism, while the plates 2 lie in planes parallel to the planes of needles. Each hole 3a in the guide plate 3 is designed to come in register with a respective needle 1 of the Jacquard mechanism. With reference to Figure 1, the holes are thus disposed in a plurality of successive rows 4, there being eight holes 3a per row, each row 4 of holes 3a corresponding to a row of needles 1 in the Jacquard mechanism. Also, the vertical plates 2 are disposed relative to the guide plate 3 in such a manner that a row 4 of holes 3a lies between two successive plates 2. In Figure 1, only a limited number of rows 4 are shown. In practice, a Jacquard mechanism may include more than one-hundred rows of needles. Between successive plates 2 there are interposed eight vertical pushers 5, there being one pusher 5 per needle 1 in the row. Each pusher 5 located between two plates 2 is mounted to slide in a common plane 5a parallel to the plates 2 between a position in which it is retracted relative to the plates 2, referred to below as a low position, and a position in which it is extended relative to the plates 2, referred to below as a high position, and each pusher is guided to move in translation by two supports 6a and 6b enabling each pusher 5 to be held in its horizontal position. In Figure 2, the apparatus is located relative to the needles of the Jacquard mechanism in a "thrust" position such that each pusher 5 is vertically beneath a needle 1. In this thrust position, the apparatus can be moved in translation relative to the needles 1 in a thrust direction represented by double-headed arrow D, which is vertical in this case. When the apparatus is in its thrust position, only the pushers 5 that are in the high position come into contact with the corresponding needles 1 via their top ends 5d referred to as their thrust ends. Thus, when the apparatus is in its thrust position and is moved vertically upwards, only those needles 1 which are associated with pushers 5 that are in the high position are raised by the apparatus as it moves. In the context of the invention, and in particular as a function of the specific type of Jacquard mechanism to which it is mounted, the apparatus may either be constantly in its thrust position, in which case it is moved only in a single translation direction relative to the needles, or else during each cycle of the Jacquard mechanism, it may be driven not only to move in translation in the thrust direction, but also to move in and out of its thrust position. In each space defined by two successive plates 2 there are mounted eight selector members 7 which lie in a common plane 7a parallel to the plates 2, i.e. in a common vertical plane in this case. Each selector member 7 is associated with a pusher 5 and can slide horizontally under drive from electromagnetic means described below between a selection position in which the corresponding pusher 5 is locked in the high position, and a retracted position in which the pusher 5 is not locked in the high position and drops under the effect of gravity into the low position. In the example of Figure 2, the eight selector members 7 are subdivided into two groups of four on either side of the pushers 5. The four selector members 7 of a given group are guided for sliding by two supports 8a and 8b that serve to hold each selector member 7 vertically. Thus, when a pusher 5 is locked in the high position by its selector member 7, and raises the corresponding needle 1 of the Jacquard mechanism, the weight of the needle is supported by the supports 8a and Bb. In the particular example shown, each selector member comprises a thin flat strip 9 of substantially rectangular shape. As can be seen in Figure 3, the plane 7a of the selector strips 9 between two plates 1 is offset relative to the plane 5a of the pushers 5 so that the pushers 5 do not impede horizontal sliding of the selector strips 9. The end 9a of each strip 9 is terminated by a lateral stud 10 extending transversely to the plane of the strip so as to intersect the plane 5a of the pushers 5. In addition, each pusher 5 has a notch 5b which is U-shaped in this case. The notch 5b of a given pusher 5 is designed so that once the pusher 5 is in its high position the notch lies at the same level and in line with the corresponding strip 9. Thus, once a pusher 5 has been moved into its high position, when the corresponding strip 9 is brought to its selection position by being caused to slide horizontally, its lateral stud 10 engages in the notch 5a of the corresponding pusher 5, thereby enabling the pusher 5 to be locked in its high position. In contrast, when the stud 10 is withdrawn from the notch 5b of the corresponding pusher, by causing the strip 9 to slide horizontally in the reverse direction, which corresponds to the dashed line position of the stud 10 in Figure 3, the pusher 5 is no longer supported vertically and it drops to its low position. In a preferred variant embodiment, electromagnetic control of the sliding of the eight selector strips 9 interposed between two plates 2 is achieved by each plate 2 being fitted with soft iron mounts 11 each comprising a base 12 having three lugs co-operating with the base 12 to form an E-shape, namely two end lugs 13a and a central lug 13b. A coil 14 is wound on the central lug 13b. The two end lugs 13a thus constitute two electromagnetic pole pieces of the same sign, while the central lug 13b constitutes a core forming an electromagnetic pole piece of sign opposite to the end poles 13a. The signs of the end poles 13a and of the central pole 13b are determined by the direction of current flow in the coil 14. Each mount 11 is fixed through the plate 2 via an opening provided for this purpose, such that the base 12 is located on the face 2a of the plate 2, with the poles 13a and 13b being positioned on the other face 2b of the plate 2. With reference to Figure 3, it can clearly be seen that the poles 13a and 13b of a coil-carrying mount 11 of a given plate 2 (bottom plate in Figure 3) faces the base 12 of the mount 11 on the adjacent plate (top plate in Figure 3), thus co-operating with said base 12 to form an electromagnetic circuit that serves to establish locally in the space between the plates 2, two opposite induced electromagnetic fields Cl and C2. These two electromagnetic fields extend transversely to the plane of the plates 2 and they are represented by dashed lines in Figure 3. In other words, the base 12 of the coil mounts 11 in each plate 2 constitute a yoke for closing the two electromagnetic fields induced by the facing coil-carrying portion on the adjacent plate, which portion is formed by two end poles 13a and by a central pole 13b. Each selector strip 9 is fitted with two permanent magnets 15a and 15b mounted in opposition. Each pair of magnets 15a and 15b of a selector strip 9 is positioned between the base 12 and the three poles 13a and 13b of a given electromagnetic circuit. In Figure 2, for reasons of clarity, the coils 14 of each electromagnetic circuit are represented by dashed lines only, with the mounts 11 of the plates 2 being omitted. As can be seen clearly in this figure, the electromagnetic circuits are distributed in two groups of four circuits each on opposite sides of the pushers 5, and the circuits in any one group are offset laterally in the plane of the plate, thereby achieving a vertical space saving. Naturally, the same offset is to be found for the pairs of magnets 15a and 15b of the strips 9 in any one group. The two magnets 15a and 15b of a strip 9 constitute a two-pole element of dimensions such that it can channel its magnetic field via one or other of the end poles 13a depending on the direction of the two induced electromagnetic fields Cl and C2, i.e. depending on the direction of current flow in the coil 14. In Figure 3, the two-pole elements constituted by the two magnets 15a and 15b of the strip 9 tend to channel the electromagnetic field via the righthand end pole 13a of the coil mount 11 of the lower plate 2, so that the strip 9 is thus subjected to a force tending to move it to the right. A first indexing abutment 16 is provided at the end 9a of the strip 9 and enables the strip to be held stably in this position, which corresponds to its selection position with the stud 10 being engaged in the notch 5b of the pusher 5. When the current carried by the coil 14 is reversed, the two induced electromagnetic fields Cl and C2 are reversed. The two-pole element formed by the two magnets 15a and 15b then seeks to channel its magnetic field via the lefthand end pole 13a, thereby causing the selector strip 9 to move to the left. A second indexing abutment 17 (Figure 2) is provided to engage the ends 9b of the strips 9. Each strip 9 is thus brought to a stable position against the abutment 17 (dashed line position in Figure 3), which position corresponds to the selector strip being retracted, its stud 10 being disengaged from the notch 5b of the pusher. The function of the two indexing abutments 16 and 17 is to prevent the two-pole element formed by the two magnets 15a and 15b from advancing to a position in which it is centered on the corresponding end pole 13a. The particular embodiment shown in Figure 3 implementing three electromagnetic pole pieces 13a and 13b, a pair of magnets 15a and 15b mounted in opposition, and two indexing abutments 16 and 17, serves advantageously to obtain a selector member 7 which remains stable in its retracted position or in its selection position, even in the event of an interruption in the power supply to the coil 14. Providing the selector member 7 is already in its retracted position or its selection position when the power supply to the coil 14 is interrupted, the two-pole element formed by the two magnets 15a and 15b attempts to center itself by means of its magnetic field either on the corresponding end pole piece 13a, i.e., in Figure 3, on the righthand end pole 13a when the selector member 7 is in its selection position, or on the lefthand end pole 13a when the selector member is in its retracted position. The selector member thus remains continuously pressed against the corresponding indexing abutment 16 or 17, even when the coil 14 is carrying no current. In this embodiment, once the selector member has been put in its retracted or its selected position, not only is there no need to maintain current in the coil 14 throughout the time that the needles of the Jacquard mechanism are to be pushed, but also the control of the Jacquard mechanism is unaffected in the event of a momentary power cut to a coil during a cycle. With reference to Figure 2, the coils 14 of the mounts 11 are powered by means of each plate 2 being fitted with a connector 18 having nine terminals 19, associated with a printed circuit 20 that serves to connect one of the two ends of each coil 14 to a single terminal 19 acting as a common ground and the other end of each coil 14 to a respective terminal 19. The terminals 19 of the connector 18 on each plate 2 are connected to a processor unit (not shown) which is programmed to deliver the appropriate control voltage to each coil 14 for each cycle of the Jacquard mechanism depending on whether or not the corresponding strip 9 is to lock the corresponding pusher 5 in its high position, which amounts to simulating a hole that has not been punched or a punched hole, respectively, in a punched card. To enable the pushers 5 to be locked in the high position, it is necessary to bring them mechanically into said position prior to locking them. This is achieved by means of a reset plate 21 which is movable in translation relative to the plates 2 and to the selector strips 9 along the axes 5e of the pushers 5, between a low position and a high position represented by dashed lines in Figure 2. In the example shown, all of the pushers 5 are constituted by rods of the same length having a bottom or "reset" end 5c projecting beneath the bottom edge of the row of plates 2, at least when the pusher 5 is in its low position. The reset plate 21 is positioned in such a manner that when it is in the low position, the reset ends 5c of the pushers 5 that are in their low positions come into contact with the top face of the plate 21. The apparatus described above with reference to Figures 1 to 3 operates as follows. On each cycle of the Jacquard mechanism, the apparatus finds itself in a reset position in which none of the pushers 5, regardless of its position, can come into contact with the needles 1. When the apparatus is in this reset position, the reset plate 21 is raised and pushes into the high position all of the pushers that were not already locked in the high position during the preceding cycle. Thereafter, while the reset plate is in its high position, the processor unit (not shown) applies appropriate voltages to each of the coils 14 so as to bring or allow to remain, where appropriate, the corresponding selector strip 9 into the desired retracted or selection position. Thereafter, the reset plate 21 is lowered. Those pushers 5 for which the corresponding selector strip 9 is in the retracted position fall under gravity to the low position. The other pushers are locked in the high position relative to the plates 2. Thereafter the entire apparatus is moved, where appropriate, into the thrust position as described above, after which it is moved along the thrust direction D for the purpose of individually lifting those needles of the Jacquard mechanism that have been selected. Advantageously, the reset plate 21 has low inertia, thus enabling it to have motion of high frequency and of relatively large amplitude imparted thereto. The back-and-forth motion of the reset plate 21 between its low position and its high position corresponds to the incremental rotation of the traditional drive cylinder used for driving punched cards. Advantageously, the up-and-down motion of the reset plate 21 is controlled by using means that already exist in the Jacquard mechanism for rotating the cylinder that has been replaced by the apparatus of the invention. The main advantage of the invention lies in the fact that it enables apparatus to be made in which the pitch e between successive plates can be very small, and is also independent of the number of needles per row in the Jacquard mechanism. In particular, it is possible to make apparatus as shown in Figures 1 to 3 that can control the needles 1 of a Jacquard mechanism in which successive rows are spaced at a pitch e of 6 mm. Another advantage of the invention lies in its modular aspect. It is very easy to modify a given apparatus to adapt it to a different Jacquard mechanism having the same pitch e between rows but including some other number of rows of needles, or some other number of needles per row. This can be done merely by removing or adding the appropriate number of plates 2, of selector members 7, and of pushers 5. It should be observed at this point that since the selector members 7 and the pushers 5 are merely slidably mounted relative to the plates 2, they can very easily be installed in or removed from the spaces between the plates, and no special tool is required for this purpose. The invention is not limited to the preferred embodiment described with reference to Figures 1 to 3. By way of non-exhaustive examples, the apparatus of the invention could be implemented in any of the following variant ways. Electromagnetic control could be provided by selector members having two-pole coil mounts. Under such circumstances, each electromagnetic circuit creates a single induced electromagnetic field and each selector member has a single permanent magnet. In this variant, when the coil is powered with a given voltage, it causes the selector member to move and come into abutment in a given position. This position may either be the retracted position or the selection position. Each selector member also includes resilient return means, e.g. a coil spring, which is compressed when the selector member is held in the abutment position by the electromagnetic means. When the power supply to the coil 14 is interrupted, the resilient return means return the selector member in the opposite direction to its retracted position or its selected position, as applicable. In another variant, the axis 5e of each pusher 5 can be horizontal. In this variant, the pushers can no longer return to the retracted position under the effect of gravity. Thus, in this variant, each pusher is fitted with resilient return means of the coil spring type which is compressed when the pusher is in its extended position and which has the function of returning the pusher to the retracted position on relaxing when the pusher is no longer selected and the reset plate leaves its position for holding the pushers in the extended position. Advantageously, the use of pushers makes it possible to implement selector members having a very short stroke, and more particularly a stroke that is shorter than the width 1 of a needle (Figure 2). This makes it possible to control the needles of a Jacquard mechanism for which the distance d between adjacent needles in the same row (Figure 2) is less than the width .1 of a needle. It has thus been possible to make a pusher apparatus as shown in Figures 1 to 3 with the distance between pushers, i.e. the distance d, being about 2 mm. However, in the context of the invention, if the distance d is not a constraint, and in particular is greater than or equal to the width 1, it is possible to control the needles directly by the selector members. Under such circumstances, each selector member should be designed to close the corresponding hole 3a in the guide plate 3. The selector members may then be constituted by flat L-shaped strips. In the embodiment shown in Figures 1 to 3, the reset plate 21 pushes against each pusher 5 via the reset end 5c thereof which is remote from the thrust end 5d thereof and which projects relative to the plates 2. The reset plate may thus advantageously be constituted by a single solid plate that is relatively thin. In another variant, the reset plate may be a perforated plate with the thrust ends 5d of the pushers 5 passing therethrough, the reset plate serving to pull the pushers into the extended position. To this end, each pusher is provided with a collar, e.g. close to its thrust end. The function of the collar is to co-operate with the reset plate so as to bring the pusher into the extended position. In this variant, there is no need for the reset end 5c of each pusher 5 to project from the plates, thus making it possible for each selector member 7 to be designed to lock the corresponding pusher 5 in the extended position by acting on the reset end thereof, in a manner similar to the Figure 4 variant of European patent application EP A 0 382 998. Finally, in another variant embodiment of the invention, the pushers 5 are placed in the extended position relative to the plates 2, not by moving the reset plate 21 in translation towards the pushers, but on the contrary by moving the assembly constituted by the plates 2 and the selector members 7 in translation relative to the reset plate 21 along the axes 5e of the pushers 5. This variant operates as follows. Before causing the selector members 7 to move, the assembly comprising the plates 2 and the selector members 7 is moved towards the reset plate 21 to occupy a position in which all of the pushers 5 are in contact with the reset plate. During this movement, those pushers 5 which are locked in the extended plate relative to the plates 2 are moved towards the reset plate 21, while the other pushers 5 which are not locked in the extended position remain stationary in contact with the reset plate 21. In this first position of the assembly comprising the plates 2 and the selector members 7, all of the pushers 5 are in the extended position relative to the plates 2. Once the assembly comprising the plates 2 and the selector members 7 has been brought to this first position, the appropriate selector members 7 are caused to move so as to lock selectively in the extended position those pushers 5 which are to act on the needles of the Jacquard mechanism during the following cycle. Once the appropriate pushers 5 are locked in the extended position, the assembly comprising the plates 2 and the selector members 7 is moved in the opposite direction relative to the reset plate. The pushers 5 locked in the extended position are entrained by the assembly to a second position in which the pushers 5 locked in the extended position come into contact with the corresponding needles of the Jacquard mechanism. The pushers 5 which are not locked relative to the plates 2 remain stationary, in contact with the reset plates 21, with the assembly comprising the plates 2, the selector members 7, and the pushers 5 that are locked in the extended position, sliding relative to the pushers 5 that are not locked. We Claim: Apparatus for automatically actuating the needles (1) of a Jacquard mechanism, which apparatus is designed firstly to be moved during each cycle of the Jacquard mechanism relative to the needles in order to push them individually in selective manner, and secondly to implement, for each needle, a selector member which is movable in a direction transverse to the thrust direction of the apparatus between a selection, first position and a retracted, second position, with displacement thereof between the selection and retraction positions being under electromagnetic control in such a manner that when the apparatus is moved it pushes only those needles of the Jacquard mechanism which are associated with a selector member in the selection position, the apparatus being characterized in that with the needles (1) of the Jacquard mechanism being disposed in successive parallel rows, it comprises a plurality of parallel plates (2) spaced apart at a pitch e identical to that of two successive rows of needles, in that the spaces between successive pairs of plates (2) have mounted therein the selector members (7) associated with the needles (1) of a given row, which selector members are movable in a common plane parallel to that of the plates (2), and a two-portion electromagnetic circuit is provided for each selector member (7) serving to create at least one induced electromagnetic field (Cl) extending transversely to the planes of the plates (2), the two portions of the electromagnetic circuit being mounted respectively on the facing faces (2a, 2b) of two successive plates and respectively constituting a coil-carrying main portion (13a, 13b, 14) having at least two opposite electromagnetic pole pieces, and a closure yoke (12) for closing the electromagnetic field and disposed facing the coil carrying main portion, and in that each selector member (7) comprises a magnetized portion which is positioned between the two portions of the associated electro magnetic circuit so as to enable displacement of the selector member to be controlled. 2. Apparatus as claimed in claim 1, wherein each plate (2) comprises on at least one of its faces the coil-carrying portions of the electromagnetic circuits, and on its other face the closure yokes for closing respective electromagnetic fields induced by the coil- carrying portions of the adjacent plate (2). 3. Apparatus as claimed in claim 2, wherein each closure yoke of a plate (2) is constituted by the base (12) of a ferromagnetic mount (11) whose portion remote from its base carries a coil, and passes through the plate (2) so that the base (12) and the coil-carrying portion of the mount are to be found on respective sides of the plate (2). 4. Apparatus as claimed in any one of claims 1 to 3, wherein each coil-carrying portion comprises three electromagnetic pole pieces, forming two end pole pieces (13a) of the same sign and a central electromagnetic pole piece (13b) of opposite sign and constituting a coil-carrying core, and in that the magnetized portion of each selector member (7) is constituted by two permanent magnets mounted in opposition, whereby controlling the direction of current flow through the coil (14) on the central pole piece (13b) causes the selector member (7) to be moved in one direction or the other so as to bring it into abutment in the selection position or in the retracted position. 5. Apparatus as claimed in any one of claims 2 to 4, wherein each plate (2) is fitted with a connector (18) for powering the coils (14), and serves as a support for a printed circuit (20) connecting each coil (14) to the connector (18). 6. Apparatus as claimed in any one of claims 1 to 5, wherein between the plates (2) and for each selector member (7) it comprises a separate pusher (5) movable relative to the plates (2) in the plane of the plates and in a direction extending transversely to the displacement axis of the selector members (7), and capable of being locked in an extended position relative to the plates (2) by the associated selector member (7), in which position the pusher (5) can push the associated needle of the Jacquarcl mechanism .. during displacement of the apparatus. 7. Apparatus as claimed in claim 6, wherein it comprises a reset plate (21), and in that the assembly constituted by the plates (2) and the selector members (7) is movable in translation relative to the reset plate (21) along the axes (5e) of the pushers (5) between a first position in which the set of pushers (5) is in contact with the reset plate (21) and in the extended position, and a second position in which only those pushers (5) which are locked in the extended position relative to the plates (2) are brought into contact with the corresponding needles (1) of the Jacquard mechanism, the pushers (5) that are not locked in the extended position not being entrained and remaining in contact with the reset plate (21). 8. Apparatus as claimed in claim 6, wherein it comprises a reset plate (21) which is movable in translation relative to the plates (2) and to the selector members (7) along the axes (5e) of the pushers (5) and which serves during each cycle of the Jacquard mechanism to bring the pushers (5) into the extended position relative to the plates (2) and to hold them there while displacement of the selector members (7) is being controlled. 9. Apparatus as claimed in claim 8, wherein, the axes (5e) of the pushers (5) are vertical, and the reset plate (21) is movable between a low position and a high position in which it supports all of the pushers (5) in the extended position, such that those pushers which are not locked in the extended position by their respective selector members (7) drop back into the retracted position under the effect of gravity when the reset plate moves from its high position to its low position. 10. Apparatus as claimed in claim 8, wherein the axes of the pushers are horizontal, and in that each pusher comprises resilient position-return means compressed whenever each pusher is held in its extended position by the reset means, and serving to return the pushers to the retracted position when the reset plate leaves that position. 11. Apparatus as claimed in any one of claims 7 to 10, wherein the pushers (5) are constituted by rods of identical length, each having a thrust, first end (5d) for coming into contact with a needle (1) and a reset, second end (5c) which projects from the row of plates and which is designed to come into contact with the reset plate (21). 12. Apparatus as claimed in claim 11, wherein the selector members (7) are constituted by flat strips (9), in that all of the pushers (5) in the gaps between successive plates (2) occupy a common plane (5a) parallel to the plates, and all of the strips (9) also occupy a common plane (7a) parallel to the plate, but offset relative to the plane (5a) of the pushers (5) such that the pushers do not interfere with displacement of the strips (9), in that each pusher comprises a notch (5b) enabling it to be locked in the extended position, and in that each strip \|9) comprises a lateral stud (10) extending transversely to the plane of the strip (9) and which engages in the notch (5b) of the corresponding pusher (5) when the strip (9) is 'moved into its selection position, thereby locking the pusher in its extended position. 13. Apparatus for automatically actuating the needles (1) of a Jacquard mechanism, substantially as herein described with reference to and as illustrated in the accompanying drawings. 14. A Jacquard mechanism fitted with apparatus as claimed in any one of claims 1 to 13.

Full Text

The present invention relates to an apparatus for automatically actuating the needles of a Jacquard mechanism.
The present invention relates to electromagnetic apparatus for automatically actuating the needles of a Jacquard mechanism, and also to a Jacquard mechanism fitted with such an apparatus. More precisely, it relates to apparatus designed to be moved relative to the needles of a Jacquard mechanism in order to push them selectively under the control of electromagnetic means to make a selection that is established automatically on each cycle of the Jacquard mechanism. More particularly, but non-exclusively, the invention serves to replace the punched cards of Jacquard mechanisms used for controlling lacemaking machines, and in particular Leavers' lacemaking machines.
Proposals have already been made, in particular in European patent EP-A-0 382 998, to replace the traditional punched cards of a Jacquard.mechanism by an electromagnetic control apparatus for pushing the needles of the Jacquard mechanism selectively. That document teaches controlling the selection of each needle of the Jacquard mechanism automatically by means of a solenoid, and more particularly a two-position solenoid having two concentric windings referred to respectively as an
(
"engagement" winding and as a "release" winding.-Electrically powering the release winding causes a selection member in the form of a rod to be extended, while electrically powering the engagement winding enables said selection rod to be retracted. The apparatus is also fitted with means enabling it to be moved relative to the needles of the Jacquard mechanism. In a first variant embodiment, shown in particular in Figure 1 of that document, the selection rod of each solenoid is associated with a passage, and has the function of closing the passage when brought into its extended position. When the apparatus comes into contact with the needles of the Jacquard mechanism, all of the
needles that are in register with respective passages that are closed by selection rods are pushed by the apparatus as it moves. In contrast, the needles of the Jacquard mechanism situated in register with passages that are not closed by respective selection rods penetrate into said passages during displacement of the apparatus and are therefore not pushed by the apparatus. In a second variant embodiment shown in Figure 4 of that document, the selection rods act on respective intermediate pushers, and serve to lock the pushers in the extended position. When a pusher is locked in the extended position, it enables the corresponding needle of the Jacquard mechanism to be pushed during displacement of the apparatus. When a pusher is not locked in the extended position, it is returned elastically by a return spring to a retracted position and it cannot come into contact with the associated needle.
The electromagnetic apparatuses described in European patent application EP-A-0 382 998 serve advantageously firstly to enable the needles of a Jacquard mechanism that need to be pushed during a given cycle to be selected automatically by appropriately controlling the electrical power supply to the windings of each solenoid associated with a needle, and secondly to enable very little energy to be used to control each solenoid. Nevertheless, the solenoids described in that document suffer from the drawback of being bulky, and as a result they are unsuitable for being adapted to select the needles of a Jacquard mechanism disposed in successive rows with small spacing between rows, and in particular a spacing of less than 1 cm.
An object of the present invention is to propose an electromagnetic apparatus that presents the advantages of the apparatuses of the above-mentioned European patent application, but made up of electromagnetic selector members that are more compact, thereby enabling it to be adapted to controlling the needles of a Jacquard
mechanism organized as successive close-together rows. More particularly, the apparatus of the invention is suitable for Jacquard mechanisms used for controlling Leavers' lacemaking machines in which the spacing between two successive rows of needles is very small, being of the order of 6 mm. Nevertheless, the invention is not limited to that particular type of Jacquard mechanism, but can be applied in general manner to any type of Jacquard mechanism controlled by needles that need to be pushed in selective manner and that are disposed in successive rows. The mechanism may be constituted, in particular, by Jacquard mechanisms having cords or hooks for controlling textile machinery, and in particular looms. The Jacquard mechanism may also be of the type described in French patent application FR-A-2 704 562 in which the needles that need to be pushed, referred to as dropper needles, control the displacement of flexible needles referred to as strikers that are disposed transversely to the drop needles. Finally, the needles of the Jacquard mechanism that need to be pushed in selective manner by the apparatus of the invention may be disposed vertically or horizontally.
In the same manner as the apparatuses described in European patent application EP-A-0 382 998, the apparatus of the invention is designed firstly to be moved during each cycle of the Jacquard mechanism relative to the needles in order to push them individually in selective manner, and secondly to implement, for each needle, a selector member which is movable in a direction transverse to the thrust direction of the apparatus between a selection, first position and a retracted, second position, with displacement thereof between the selection and retraction positions being under electromagnetic control in such a manner that when the apparatus is moved it pushes only those needles of the Jacquard mechanism which are associated with a selector member in the selection position.
In a manner characteristic of the invention, with the needles of the Jacquard mechanism being disposed in successive parallel rows, the apparatus comprises a plurality of parallel plates spaced apart at a pitch e identical to that of two successive rows of needles; the spaces between successive pairs of plates have mounted therein the selector members associated with the needles of a given row, which selector members are movable in a common plane parallel to that of the plates, and a two-portion electromagnetic circuit is provided for each selector member serving to create at least one induced electromagnetic field extending transversely to the planes of the plates, the two portions of the electromagnetic circuit being mounted respectively on the facing faces of two successive plates and respectively constituting a coil-carrying main portion having at least two opposite electromagnetic pole pieces, and a closure yoke for closing the electromagnetic field and disposed facing the coil-carrying main portion; and each selector member includes a magnetized portion which is positioned between the two portions of the associated electromagnetic circuit so as to enable displacement of the selector member to be controlled.
In the context of the invention, each plate could be fitted on each of its two faces either solely with coil-carrying portions, or else solely with closure yokes for closing the electromagnetic field. In which case, plates having coil-carrying portions and plates having closure yokes are placed in alternation. In another variant embodiment, the plates of the apparatus of the invention are all of the same type, and each plate has the coil-carrying portions of the electromagnetic circuits on one of its faces and the closure yokes on its other face for the purpose of closing the respective electromagnetic fields induced by the coil-carrying portions of the adjacent plate. This variant has the advantage of reducing manufacturing costs since all of the plates areidentical. In the context of this variant, the coil-carrying portions and the closure yokes of a plate may be separate, e.g. being stuck to the two respective faces of the plate. However, in order to simplify manufacture of the plates, and thereby further reducing the cost of manufacturing them, it is preferable for each closure yoke of a plate to be constituted by the base of a ferromagnetic mount whose portion remote from the base carries a coil, and which is fixed through the plate such that the base and the coil-carrying portion of the mount are to be found on respective sides of the plate.
Preferably, the apparatus includes a separate pusher movable relative to the plates in the plane of the plates and in a direction extending transversely to the displacement axis of the selector members, and capable of being locked in an extended position relative to the plates by the associated selector member, in which position the pusher can push the associated needle of the Jacquard mechanism during displacement of the apparatus.
It is necessary for each pusher to be capable of being placed in the extended position relative to the plates and to the selector members by any appropriate means in order to be locked in said position, where appropriate. In a first variant, this can be achieved by moving the assembly formed by the parallel plates and the selector members relative to the pushers. In this first variant, the apparatus includes a reset plate and the assembly constituted by the parallel plates and the selector members is movable in translation relative to the reset plate along the axes of the pushers between a first position in which the set of pushers is in contact with the reset plate and in the extended position, and a second position in which only those pushers which are locked in the extended position relative to the plates are brought into contact with the corresponding needles of the Jacquard mechanism, the pushers that are not
locked in the extended position not being entrained and remaining in contact with the reset plate.
The relatively large inertia of the assembly formed by the parallel plates and the selector members limits the frequency and/or the amplitude of the motion that can be imparted thereto. In order to mitigate this drawback, a second variant the apparatus of the invention includes a reset plate which is movable in translation relative to the plates and to the selector members along the axes of the pushers and which serves during each cycle of the Jacquard mechanism to bring the pushers into the extended position relative to the plates and to hold them there while displacement of the selector members is being controlled.
More generally, the reset plate of the invention can be used in any apparatus enabling the needles of a Jacquard mechanism to be pushed automatically and selectively by means of pushers that can be locked in an extended position by selector members. This additional characteristic of the invention is thus independent of implementing the main means of the invention, i.e. the particular structure as a plurality of parallel plates with, in each space between plates, a plurality of electromagnetic circuits in two portions, each enabling at least one electromagnetic field to be induced transversely to the plane of the plates for the purpose of controlling the displacement of each needle selector member in a given row. In particular, the reset plate of the invention could be fitted to the variant of Figure 4 of European patent application EP-A-0 382 998.
According to the present invention there is provided an apparatus for automatically actuating the needles of a Jacquard mechanism, which apparatus is designed firstly to be moved during each cycle of the Jacquard mechanism relative to the needles in order to push them individually in selective manner, and secondly to implement, for each needle, a selector member which is movable in a direction transverse to the thrust direction of the apparatus between a selection, first position and a retracted, second position, with displacement thereof between the selection and retraction positions being under electromagnetic control in such a manner that when the apparatus is moved it pushes only those needles of the Jacquard mechanism which are associated with a selector member in the selection position, the apparatus being characterized in that with the needles of the Jacquard mechanism being disposed in successive parallel rows, it comprises a plurality of parallel plates spaced apart at a pitch e identical to that ui' two successive rows of needles, in that the spaces between successive pairs of plates have mounted therein the selector members associated with the needles of a given row, which selector members are movable in a common plane parallel to that of the plates, and a two- portion electromagnetic circuit is provided for each selector member serving to create at least one induced electromagnetic field extending transversely to the planes of the plates, the two portions of the electromagnetic circuit being mounted respectively on the facing faces of two successive plates and respectively constituting a coil-carrying main portion having at least two opposite electromagnetic pole pieces, and a closure yoke for closing the electromagnetic field and disposed facing the coil carrying main portion, and in that each selector member comprises a magnetized portion which is positioed between the two portions of the associated electromagnetic circuit so as to enable displacement of the selector member to be controlled. Other characteristics and advantages of the invention appear more clearly on reading the description below of a preferred embodiment of the invention, which description is given by way of non-limiting example and is made with reference to the accompanying drawing, in which:
• Figure 1 is a fragmentary plan view of apparatus
of the invention for automatically selecting dropper
needles of a Jacquard mechanism, which needles are
disposed in parallel rows with eight needles per row;
• Figure 2 is a section view in a vertical plane of
the Figure 1 apparatus between two successive plates; and
• Figure 3 is a detail section view on a horizontal plane through the apparatus of Figure 1, showing a selector member between two successive plates.
The apparatus of Figures 1 to 3 is designed to be mounted to a Jacquard mechanism (not shown) having dropper needles 1, more commonly known as "droppers", of the kind used for controlling a Leavers' lacemaking machine. It replaces the rotary cylinder serving as a support 4 and serving to drive the chain of punched cards traditionally used for selectively pushing the needles of the Jacquard mechanism. In the particular example described below, the needles 1 of the Jacquard mechanism are disposed in a plurality of successive rows that are spaced apart at a constant pitch e, with each row having eight needles.
With reference to Figures 1 and 2, the apparatus comprises a plurality of identical parallel plates 2 which are regularly spaced apart at a pitch e identical to that of the rows of needles in the Jacquard mechanism, and which are secured to a pierced guide plate 3. In the particular example shown, with the apparatus being designed to push the vertically dropping needles 1 of a Jacquard mechanism, the plates 2 are vertical while the pierced guide plate 3 is horizontal. More generally, the pierced card plate 3 lies in a plane extending transversely relative to the needles 1 of the Jacquard mechanism, while the plates 2 lie in planes parallel to the planes of needles.
Each hole 3a in the guide plate 3 is designed to come in register with a respective needle 1 of the Jacquard mechanism. With reference to Figure 1, the
holes are thus disposed in a plurality of successive rows 4, there being eight holes 3a per row, each row 4 of holes 3a corresponding to a row of needles 1 in the Jacquard mechanism. Also, the vertical plates 2 are disposed relative to the guide plate 3 in such a manner that a row 4 of holes 3a lies between two successive plates 2. In Figure 1, only a limited number of rows 4 are shown. In practice, a Jacquard mechanism may include more than one-hundred rows of needles.
Between successive plates 2 there are interposed eight vertical pushers 5, there being one pusher 5 per needle 1 in the row. Each pusher 5 located between two plates 2 is mounted to slide in a common plane 5a parallel to the plates 2 between a position in which it is retracted relative to the plates 2, referred to below as a low position, and a position in which it is extended relative to the plates 2, referred to below as a high position, and each pusher is guided to move in translation by two supports 6a and 6b enabling each pusher 5 to be held in its horizontal position.
In Figure 2, the apparatus is located relative to the needles of the Jacquard mechanism in a "thrust" position such that each pusher 5 is vertically beneath a needle 1. In this thrust position, the apparatus can be moved in translation relative to the needles 1 in a thrust direction represented by double-headed arrow D, which is vertical in this case. When the apparatus is in its thrust position, only the pushers 5 that are in the high position come into contact with the corresponding needles 1 via their top ends 5d referred to as their thrust ends. Thus, when the apparatus is in its thrust position and is moved vertically upwards, only those needles 1 which are associated with pushers 5 that are in the high position are raised by the apparatus as it moves. In the context of the invention, and in particular as a function of the specific type of Jacquard mechanism to which it is mounted, the apparatus may
either be constantly in its thrust position, in which case it is moved only in a single translation direction relative to the needles, or else during each cycle of the Jacquard mechanism, it may be driven not only to move in translation in the thrust direction, but also to move in and out of its thrust position.
In each space defined by two successive plates 2 there are mounted eight selector members 7 which lie in a common plane 7a parallel to the plates 2, i.e. in a common vertical plane in this case. Each selector member 7 is associated with a pusher 5 and can slide horizontally under drive from electromagnetic means described below between a selection position in which the corresponding pusher 5 is locked in the high position, and a retracted position in which the pusher 5 is not locked in the high position and drops under the effect of gravity into the low position.
In the example of Figure 2, the eight selector members 7 are subdivided into two groups of four on either side of the pushers 5. The four selector members 7 of a given group are guided for sliding by two supports 8a and 8b that serve to hold each selector member 7 vertically. Thus, when a pusher 5 is locked in the high position by its selector member 7, and raises the corresponding needle 1 of the Jacquard mechanism, the weight of the needle is supported by the supports 8a and Bb.
In the particular example shown, each selector member comprises a thin flat strip 9 of substantially rectangular shape. As can be seen in Figure 3, the plane 7a of the selector strips 9 between two plates 1 is offset relative to the plane 5a of the pushers 5 so that the pushers 5 do not impede horizontal sliding of the selector strips 9. The end 9a of each strip 9 is terminated by a lateral stud 10 extending transversely to the plane of the strip so as to intersect the plane 5a of the pushers 5. In addition, each pusher 5 has a notch 5b
which is U-shaped in this case. The notch 5b of a given pusher 5 is designed so that once the pusher 5 is in its high position the notch lies at the same level and in line with the corresponding strip 9. Thus, once a pusher 5 has been moved into its high position, when the corresponding strip 9 is brought to its selection position by being caused to slide horizontally, its lateral stud 10 engages in the notch 5a of the corresponding pusher 5, thereby enabling the pusher 5 to be locked in its high position. In contrast, when the stud 10 is withdrawn from the notch 5b of the corresponding pusher, by causing the strip 9 to slide horizontally in the reverse direction, which corresponds to the dashed line position of the stud 10 in Figure 3, the pusher 5 is no longer supported vertically and it drops to its low position.
In a preferred variant embodiment, electromagnetic control of the sliding of the eight selector strips 9 interposed between two plates 2 is achieved by each plate 2 being fitted with soft iron mounts 11 each comprising a base 12 having three lugs co-operating with the base 12 to form an E-shape, namely two end lugs 13a and a central lug 13b. A coil 14 is wound on the central lug 13b. The two end lugs 13a thus constitute two electromagnetic pole pieces of the same sign, while the central lug 13b constitutes a core forming an electromagnetic pole piece of sign opposite to the end poles 13a. The signs of the end poles 13a and of the central pole 13b are determined by the direction of current flow in the coil 14.
Each mount 11 is fixed through the plate 2 via an opening provided for this purpose, such that the base 12 is located on the face 2a of the plate 2, with the poles 13a and 13b being positioned on the other face 2b of the plate 2. With reference to Figure 3, it can clearly be seen that the poles 13a and 13b of a coil-carrying mount 11 of a given plate 2 (bottom plate in Figure 3) faces the base 12 of the mount 11 on the adjacent plate (top
plate in Figure 3), thus co-operating with said base 12 to form an electromagnetic circuit that serves to establish locally in the space between the plates 2, two opposite induced electromagnetic fields Cl and C2. These two electromagnetic fields extend transversely to the plane of the plates 2 and they are represented by dashed lines in Figure 3. In other words, the base 12 of the coil mounts 11 in each plate 2 constitute a yoke for closing the two electromagnetic fields induced by the facing coil-carrying portion on the adjacent plate, which portion is formed by two end poles 13a and by a central pole 13b.
Each selector strip 9 is fitted with two permanent magnets 15a and 15b mounted in opposition. Each pair of magnets 15a and 15b of a selector strip 9 is positioned between the base 12 and the three poles 13a and 13b of a given electromagnetic circuit. In Figure 2, for reasons of clarity, the coils 14 of each electromagnetic circuit are represented by dashed lines only, with the mounts 11 of the plates 2 being omitted. As can be seen clearly in this figure, the electromagnetic circuits are distributed in two groups of four circuits each on opposite sides of the pushers 5, and the circuits in any one group are offset laterally in the plane of the plate, thereby achieving a vertical space saving. Naturally, the same offset is to be found for the pairs of magnets 15a and 15b of the strips 9 in any one group.
The two magnets 15a and 15b of a strip 9 constitute a two-pole element of dimensions such that it can channel its magnetic field via one or other of the end poles 13a depending on the direction of the two induced electromagnetic fields Cl and C2, i.e. depending on the direction of current flow in the coil 14. In Figure 3, the two-pole elements constituted by the two magnets 15a and 15b of the strip 9 tend to channel the electromagnetic field via the righthand end pole 13a of the coil mount 11 of the lower plate 2, so that the strip 9 is
thus subjected to a force tending to move it to the right. A first indexing abutment 16 is provided at the end 9a of the strip 9 and enables the strip to be held stably in this position, which corresponds to its selection position with the stud 10 being engaged in the notch 5b of the pusher 5. When the current carried by the coil 14 is reversed, the two induced electromagnetic fields Cl and C2 are reversed. The two-pole element formed by the two magnets 15a and 15b then seeks to channel its magnetic field via the lefthand end pole 13a, thereby causing the selector strip 9 to move to the left. A second indexing abutment 17 (Figure 2) is provided to engage the ends 9b of the strips 9. Each strip 9 is thus brought to a stable position against the abutment 17 (dashed line position in Figure 3), which position corresponds to the selector strip being retracted, its stud 10 being disengaged from the notch 5b of the pusher. The function of the two indexing abutments 16 and 17 is to prevent the two-pole element formed by the two magnets 15a and 15b from advancing to a position in which it is centered on the corresponding end pole 13a.
The particular embodiment shown in Figure 3 implementing three electromagnetic pole pieces 13a and 13b, a pair of magnets 15a and 15b mounted in opposition, and two indexing abutments 16 and 17, serves advantageously to obtain a selector member 7 which remains stable in its retracted position or in its selection position, even in the event of an interruption in the power supply to the coil 14. Providing the selector member 7 is already in its retracted position or its selection position when the power supply to the coil 14 is interrupted, the two-pole element formed by the two magnets 15a and 15b attempts to center itself by means of its magnetic field either on the corresponding end pole piece 13a, i.e., in Figure 3, on the righthand end pole 13a when the selector member 7 is in its selection position, or on the lefthand end pole 13a when the
selector member is in its retracted position. The selector member thus remains continuously pressed against the corresponding indexing abutment 16 or 17, even when the coil 14 is carrying no current. In this embodiment, once the selector member has been put in its retracted or its selected position, not only is there no need to maintain current in the coil 14 throughout the time that the needles of the Jacquard mechanism are to be pushed, but also the control of the Jacquard mechanism is unaffected in the event of a momentary power cut to a coil during a cycle.
With reference to Figure 2, the coils 14 of the mounts 11 are powered by means of each plate 2 being fitted with a connector 18 having nine terminals 19, associated with a printed circuit 20 that serves to connect one of the two ends of each coil 14 to a single terminal 19 acting as a common ground and the other end of each coil 14 to a respective terminal 19. The terminals 19 of the connector 18 on each plate 2 are connected to a processor unit (not shown) which is programmed to deliver the appropriate control voltage to each coil 14 for each cycle of the Jacquard mechanism depending on whether or not the corresponding strip 9 is to lock the corresponding pusher 5 in its high position, which amounts to simulating a hole that has not been punched or a punched hole, respectively, in a punched card.
To enable the pushers 5 to be locked in the high position, it is necessary to bring them mechanically into said position prior to locking them. This is achieved by means of a reset plate 21 which is movable in translation relative to the plates 2 and to the selector strips 9 along the axes 5e of the pushers 5, between a low position and a high position represented by dashed lines in Figure 2. In the example shown, all of the pushers 5 are constituted by rods of the same length having a bottom or "reset" end 5c projecting beneath the bottom
edge of the row of plates 2, at least when the pusher 5 is in its low position. The reset plate 21 is positioned in such a manner that when it is in the low position, the reset ends 5c of the pushers 5 that are in their low positions come into contact with the top face of the plate 21.
The apparatus described above with reference to Figures 1 to 3 operates as follows. On each cycle of the Jacquard mechanism, the apparatus finds itself in a reset position in which none of the pushers 5, regardless of its position, can come into contact with the needles 1. When the apparatus is in this reset position, the reset plate 21 is raised and pushes into the high position all of the pushers that were not already locked in the high position during the preceding cycle. Thereafter, while the reset plate is in its high position, the processor unit (not shown) applies appropriate voltages to each of the coils 14 so as to bring or allow to remain, where appropriate, the corresponding selector strip 9 into the desired retracted or selection position. Thereafter, the reset plate 21 is lowered. Those pushers 5 for which the corresponding selector strip 9 is in the retracted position fall under gravity to the low position. The other pushers are locked in the high position relative to the plates 2. Thereafter the entire apparatus is moved, where appropriate, into the thrust position as described above, after which it is moved along the thrust direction D for the purpose of individually lifting those needles of the Jacquard mechanism that have been selected.
Advantageously, the reset plate 21 has low inertia, thus enabling it to have motion of high frequency and of relatively large amplitude imparted thereto. The back-and-forth motion of the reset plate 21 between its low position and its high position corresponds to the incremental rotation of the traditional drive cylinder used for driving punched cards. Advantageously, the up-and-down motion of the reset plate 21 is controlled by
using means that already exist in the Jacquard mechanism for rotating the cylinder that has been replaced by the apparatus of the invention.
The main advantage of the invention lies in the fact that it enables apparatus to be made in which the pitch e between successive plates can be very small, and is also independent of the number of needles per row in the Jacquard mechanism. In particular, it is possible to make apparatus as shown in Figures 1 to 3 that can control the needles 1 of a Jacquard mechanism in which successive rows are spaced at a pitch e of 6 mm.
Another advantage of the invention lies in its modular aspect. It is very easy to modify a given apparatus to adapt it to a different Jacquard mechanism having the same pitch e between rows but including some other number of rows of needles, or some other number of needles per row. This can be done merely by removing or adding the appropriate number of plates 2, of selector members 7, and of pushers 5. It should be observed at this point that since the selector members 7 and the pushers 5 are merely slidably mounted relative to the plates 2, they can very easily be installed in or removed from the spaces between the plates, and no special tool is required for this purpose.
The invention is not limited to the preferred embodiment described with reference to Figures 1 to 3. By way of non-exhaustive examples, the apparatus of the invention could be implemented in any of the following variant ways.
Electromagnetic control could be provided by selector members having two-pole coil mounts. Under such circumstances, each electromagnetic circuit creates a single induced electromagnetic field and each selector member has a single permanent magnet. In this variant, when the coil is powered with a given voltage, it causes the selector member to move and come into abutment in a given position. This position may either be the retracted position or the selection position. Each selector member also includes resilient return means, e.g. a coil spring, which is compressed when the selector member is held in the abutment position by the electromagnetic means. When the power supply to the coil 14 is interrupted, the resilient return means return the selector member in the opposite direction to its retracted position or its selected position, as applicable.
In another variant, the axis 5e of each pusher 5 can be horizontal. In this variant, the pushers can no longer return to the retracted position under the effect of gravity. Thus, in this variant, each pusher is fitted with resilient return means of the coil spring type which is compressed when the pusher is in its extended position and which has the function of returning the pusher to the retracted position on relaxing when the pusher is no longer selected and the reset plate leaves its position for holding the pushers in the extended position.
Advantageously, the use of pushers makes it possible to implement selector members having a very short stroke, and more particularly a stroke that is shorter than the width 1 of a needle (Figure 2). This makes it possible to control the needles of a Jacquard mechanism for which the distance d between adjacent needles in the same row (Figure 2) is less than the width .1 of a needle. It has thus been possible to make a pusher apparatus as shown in Figures 1 to 3 with the distance between pushers, i.e. the distance d, being about 2 mm. However, in the context of the invention, if the distance d is not a constraint, and in particular is greater than or equal to the width 1, it is possible to control the needles directly by the selector members. Under such circumstances, each selector member should be designed to close the corresponding hole 3a in the guide plate 3. The selector members may then be constituted by flat L-shaped strips.
In the embodiment shown in Figures 1 to 3, the reset plate 21 pushes against each pusher 5 via the reset end 5c thereof which is remote from the thrust end 5d thereof and which projects relative to the plates 2. The reset plate may thus advantageously be constituted by a single solid plate that is relatively thin. In another variant, the reset plate may be a perforated plate with the thrust ends 5d of the pushers 5 passing therethrough, the reset plate serving to pull the pushers into the extended position. To this end, each pusher is provided with a collar, e.g. close to its thrust end. The function of the collar is to co-operate with the reset plate so as to bring the pusher into the extended position. In this variant, there is no need for the reset end 5c of each pusher 5 to project from the plates, thus making it possible for each selector member 7 to be designed to lock the corresponding pusher 5 in the extended position by acting on the reset end thereof, in a manner similar to the Figure 4 variant of European patent application EP A 0 382 998.
Finally, in another variant embodiment of the invention, the pushers 5 are placed in the extended position relative to the plates 2, not by moving the reset plate 21 in translation towards the pushers, but on the contrary by moving the assembly constituted by the plates 2 and the selector members 7 in translation relative to the reset plate 21 along the axes 5e of the pushers 5. This variant operates as follows. Before causing the selector members 7 to move, the assembly comprising the plates 2 and the selector members 7 is moved towards the reset plate 21 to occupy a position in which all of the pushers 5 are in contact with the reset plate. During this movement, those pushers 5 which are locked in the extended plate relative to the plates 2 are moved towards the reset plate 21, while the other pushers 5 which are not locked in the extended position remain stationary in contact with the reset plate 21. In this
first position of the assembly comprising the plates 2 and the selector members 7, all of the pushers 5 are in the extended position relative to the plates 2. Once the assembly comprising the plates 2 and the selector members 7 has been brought to this first position, the appropriate selector members 7 are caused to move so as to lock selectively in the extended position those pushers 5 which are to act on the needles of the Jacquard mechanism during the following cycle. Once the appropriate pushers 5 are locked in the extended position, the assembly comprising the plates 2 and the selector members 7 is moved in the opposite direction relative to the reset plate. The pushers 5 locked in the extended position are entrained by the assembly to a second position in which the pushers 5 locked in the extended position come into contact with the corresponding needles of the Jacquard mechanism. The pushers 5 which are not locked relative to the plates 2 remain stationary, in contact with the reset plates 21, with the assembly comprising the plates 2, the selector members 7, and the pushers 5 that are locked in the extended position, sliding relative to the pushers 5 that are not locked.

We Claim:
Apparatus for automatically actuating the needles (1) of a Jacquard mechanism, which apparatus is designed firstly to be moved during each cycle of the Jacquard mechanism relative to the needles in order to push them individually in selective manner, and secondly to implement, for each needle, a selector member which is movable in a direction transverse to the thrust direction of the apparatus between a selection, first position and a retracted, second position, with displacement thereof between the selection and retraction positions being under electromagnetic control in such a manner that when the apparatus is moved it pushes only those needles of the Jacquard mechanism which are associated with a selector member in the selection position, the apparatus being characterized in that with the needles (1) of the Jacquard mechanism being disposed in successive parallel rows, it comprises a plurality of parallel plates (2) spaced apart at a pitch e identical to that of two successive rows of needles, in that the spaces between successive pairs of plates (2) have mounted therein the selector members (7) associated with the needles (1) of a given row, which selector members are movable in a common plane parallel to that of the plates (2), and a two-portion electromagnetic circuit is provided for each selector member (7) serving to create at least one induced electromagnetic field (Cl) extending transversely to the planes of the plates (2), the two portions of the electromagnetic circuit being mounted respectively on the facing faces (2a, 2b) of two successive plates and respectively constituting a coil-carrying main portion (13a, 13b, 14) having at least two opposite electromagnetic pole pieces, and a closure yoke (12) for closing the electromagnetic field and disposed facing the coil carrying main portion, and in that each selector member (7) comprises a magnetized portion which is positioned between the two portions of the associated electro magnetic circuit

so as to enable displacement of the selector member to be controlled.
2. Apparatus as claimed in claim 1, wherein each plate (2) comprises
on at least one of its faces the coil-carrying portions of the
electromagnetic circuits, and on its other face the closure yokes for
closing respective electromagnetic fields induced by the coil-
carrying portions of the adjacent plate (2).
3. Apparatus as claimed in claim 2, wherein each closure yoke of a
plate (2) is constituted by the base (12) of a ferromagnetic mount
(11) whose portion remote from its base carries a coil, and passes
through the plate (2) so that the base (12) and the coil-carrying
portion of the mount are to be found on respective sides of the
plate (2).

4. Apparatus as claimed in any one of claims 1 to 3, wherein each
coil-carrying portion comprises three electromagnetic pole pieces,
forming two end pole pieces (13a) of the same sign and a central
electromagnetic pole piece (13b) of opposite sign and constituting a
coil-carrying core, and in that the magnetized portion of each
selector member (7) is constituted by two permanent magnets
mounted in opposition, whereby controlling the direction of
current flow through the coil (14) on the central pole piece (13b)
causes the selector member (7) to be moved in one direction or the
other so as to bring it into abutment in the selection position or in
the retracted position.
5. Apparatus as claimed in any one of claims 2 to 4, wherein each
plate (2) is fitted with a connector (18) for powering the coils (14),
and serves as a support for a printed circuit (20) connecting each
coil (14) to the connector (18).

6. Apparatus as claimed in any one of claims 1 to 5, wherein between
the plates (2) and for each selector member (7) it comprises a
separate pusher (5) movable relative to the plates (2) in the plane
of the plates and in a direction extending transversely to the
displacement axis of the selector members (7), and capable of
being locked in an extended position relative to the plates (2) by
the associated selector member (7), in which position the pusher
(5) can push the associated needle of the Jacquarcl mechanism
.. during displacement of the apparatus.
7. Apparatus as claimed in claim 6, wherein it comprises a reset
plate (21), and in that the assembly constituted by the plates (2)
and the selector members (7) is movable in translation relative to
the reset plate (21) along the axes (5e) of the pushers (5) between a
first position in which the set of pushers (5) is in contact with the
reset plate (21) and in the extended position, and a second
position in which only those pushers (5) which are locked in the
extended position relative to the plates (2) are brought into contact
with the corresponding needles (1) of the Jacquard mechanism,
the pushers (5) that are not locked in the extended position not
being entrained and remaining in contact with the reset plate (21).
8. Apparatus as claimed in claim 6, wherein it comprises a reset
plate (21) which is movable in translation relative to the plates (2)
and to the selector members (7) along the axes (5e) of the pushers
(5) and which serves during each cycle of the Jacquard
mechanism to bring the pushers (5) into the extended position
relative to the plates (2) and to hold them there while displacement
of the selector members (7) is being controlled.
9. Apparatus as claimed in claim 8, wherein, the axes (5e) of the
pushers (5) are vertical, and the reset plate (21) is movable
between a low position and a high position in which it supports all
of the pushers (5) in the extended position, such that those
pushers which are not locked in the extended position by their
respective selector members (7) drop back into the retracted
position under the effect of gravity when the reset plate moves
from its high position to its low position.
10. Apparatus as claimed in claim 8, wherein the axes of the pushers
are horizontal, and in that each pusher comprises resilient
position-return means compressed whenever each pusher is held
in its extended position by the reset means, and serving to return
the pushers to the retracted position when the reset plate leaves
that position.
11. Apparatus as claimed in any one of claims 7 to 10, wherein the
pushers (5) are constituted by rods of identical length, each having
a thrust, first end (5d) for coming into contact with a needle (1)
and a reset, second end (5c) which projects from the row of plates
and which is designed to come into contact with the reset plate
(21).
12. Apparatus as claimed in claim 11, wherein the selector members (7) are constituted by flat strips (9), in that all of the pushers (5) in the gaps between successive plates (2) occupy a common plane (5a) parallel to the plates, and all of the strips (9) also occupy a common plane (7a) parallel to the plate, but offset relative to the plane (5a) of the pushers (5) such that the pushers do not interfere with displacement of the strips (9), in that each pusher comprises a notch (5b) enabling it to be locked in the extended position, and in that each strip |9) comprises a lateral stud (10) extending transversely to the plane of the strip (9) and which engages in the
notch (5b) of the corresponding pusher (5) when the strip (9) is 'moved into its selection position, thereby locking the pusher in its extended position.
13. Apparatus for automatically actuating the needles (1) of a
Jacquard mechanism, substantially as herein described with
reference to and as illustrated in the accompanying drawings.
14. A Jacquard mechanism fitted with apparatus as claimed in any
one of claims 1 to 13.

Documents:

683-del-1997-abstract.pdf

683-del-1997-claims.pdf

683-del-1997-correspondence-others.pdf

683-del-1997-correspondence-po.pdf

683-del-1997-description (complete).pdf

683-del-1997-drawings.pdf

683-del-1997-form-1.pdf

683-del-1997-form-13.pdf

683-del-1997-form-19.pdf

683-del-1997-form-2.pdf

683-del-1997-form-3.pdf

683-del-1997-form-4.pdf

683-del-1997-form-6.pdf

683-del-1997-gpa.pdf

683-del-1997-petition-137.pdf

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Patent Number

222182

Indian Patent Application Number

683/DEL/1997

PG Journal Number

33/2008

Publication Date

15-Aug-2008

Grant Date

28-Jul-2008

Date of Filing

18-Mar-1997

Name of Patentee

DENTELLES DARQUER

Applicant Address

56, RUE DES QUATRE COINS, 62100 CALAIS, FRANCE.

Inventors:

#	Inventor's Name	Inventor's Address
1	DUHAMEL FRANCK	682, RUE GOUDENOVE- 62610 BREMES LES ANDRES-FRANCE

PCT International Classification Number

D04C 5/18

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA