Title of Invention

A WIPER DEVICE FOR WINDSHIELDS OF MOTOR VEHICLES

Abstract

A wiper device for windshields of motor vehicles is proposed, which wiper device is provided with a driven wiper arm which is guided on the motor vehicle and is movable between reversal positions, and on the free end of which a pivot pin is arranged and is held at one end on said wiper arm, the pivot axis of which pivot pin extends transversely to the wiper-arm longitudinal axis and essentially in the direction of movement of the wiper arm. A wiper blade which can swing about the pivot axis is mounted on the pivot pin, the wiper device having means for securing the wiper blade on the pivot pin. An especially cost-effective wiper device is obtained if the securing means for the wiper blade are arranged on the wiper arm and interact on that side of the wiper blade which faces away from the latter with a wiper-blade-side stop.

Full Text

Wiper device for windshields of motor vehicles Prior art The invention is based on a wiper device according to the generic type of Claim 1. In a known wiper device of this type (DE 16 55 410 Al) , the wiper arm and the wiper blade, in a view directed toward the windshield to be wiped, are arranged side by side or, with regard to the working direction of the wiper device, one behind the other. As a result, a lower overall height for the wiper device is achieved than is possible in wiper devices in which the wiper arm is located above the wiper blade (DE 15 05 397 Al) . The lower overall height of the wiper device of the generic type results in advantages with regard to the lifting behavior of the wiper blade from the windshield, in particular at high travel speeds. So that the wiper blade is secured on the pivot pin during the wiping operation, in the known wiper device the pivot pin arranged laterally on the wiper arm is provided in its center section with an annular groove, and a leaf spring, which can be deflected against spring force and is secured at one end to the wiper blade, plunges into this annular groove after the wiper blade has been mounted on the pivot pin and ensures together with the side walls of the annular groove that the wiper blade is secured to the wiper arm. The arrangement and design of such securing means is costly, since, on the one hand, the pivot pin has to be provided with the annular groove and, on the other hand, when the wiper blade is exchanged, the new wiper blade has to be provided with a corresponding leaf spring. In another known wiper device (DE 26 40 399 Al) , the pivot pin and the securing means formed by a hinged clip are certainly arranged on the same component of the wiper device. However, since this component is the wiper blade, not only is the hinged clip lost but so too is the pivot pin when the wiper blade is exchanged. Advantages of the invention In the wiper device according to the invention having the characterizing features of Claim 1, both the securing means and the pivot pin are retained on the wiper arm when the wiper blade is exchanged. The wiper-blade- side securing means - that is the stop - can be formed by that corresponding side cheek of the wiper blade which faces away from the wiper arm and is always present. A special configuration of this side cheek is not necessary. A wiper device which is of especially low construction and is therefore fluidically favorable is obtained if the wiper blade has a supporting element which is elongated in a band-like manner, is produced from an elastic material and is intended for a wiper strip, which can be brought into contact with the windshield to be wiped, and on whose band surface facing away from the windshield a coupling part belonging to a connection device and having the bearing aperture for the pivot pin is arranged. In a configuration of the invention, the securing means of the wiper arm are formed by supporting regions which are formed on the latter, are arranged at a distance from one another in the wiping direction and are directed toward one another, and between which fitting regions of the wiper blade which point away from one another are arranged. As a result, the idea behind the invention is realized in a cost-effective manner. An especially robust and thus operationally reliable wiper device is obtained if one supporting region is arranged on a pivoted lever of the wiper arm, and the pivoted lever has an extension which projects in the direction of the extent of the pivot axis and crosses the wiper blade, and on the free end of which a leg directed toward the windshield is arranged, that side of said leg which faces the pivoted lever forming the other supporting region. In order to limit the length of the wiper arm to the requisite dimension, the distance from the free end of the wiper arm to the pivot axis is less than the distance from the free end of the wiper arm to the extension. In a development of the invention, provision is made for the bearing bore, as viewed in the longitudinal direction of the wiper blade, to be arranged in the coupling part close to one end of the latter, and furthermore for the coupling part to be lower at least in the region of the extension and with reference to the supporting element than in the region of the bearing bore. The extension may therefore be arranged where the coupling part is lower, so that, due to the arrangement of the extension in the crossing region, it is not necessary to enlarge the overall height without the stability of the coupling part in the region of the highly loaded bearing bore suffering as a result. This low region of the coupling part is expediently obtained by virtue of the fact that the coupling part, in the region of the extension arranged on the wiper arm, is provided with a groove, which is open toward the top side facing away from the supporting element and in which the extension crosses the coupling part. If the wiper arm together with the wiper blade has to be swung away from the windshield, for example for exchanging the wiper blade, uncontrolled release of the wiper blade from the wiper arm can be prevented owing to the fact that, as measured in the longitudinal direction of the wiper blade, the distance from the bearing bore across the transverse groove up to one end of the wiper blade is greater than to the other end of the wiper blade. As a result, the half of the wiper blade which lies next to the wiper arm is rotated toward the extension on account of the displaced center of gravity, so that the wiper blade automatically comes to lie between the leg of the extension and the wiper arm or its pivoted lever and is secured there. Unintentional release of the wiper blade from the wiper arm is therefore not possible, since the wiper blade, for this purpose, has to be pivoted relative to the wiper arm in such a way that the wiper blade moves out of the securing region of the leg. The fitting regions of the wiper blade are designed in an especially simple manner if they are formed on the two longitudinal sides of the coupling part opposite one another. To minimize the lateral play between wiper blade and the supporting regions of the wiper arm, the distance between the fitting regions of the wiper blade, as measured in the direction of the pivot axis, is matched to the distance between the supporting regions of the wiper arm, since in this way the side walls of the groove absorb at least some of the forces acting on the wiper blade ~ which may arise, for example, on account of varying dirt accumulation on the windshield - and thus relieve the load on the pivoted pin or the bearing pin. A guidance aid for the wiper blade and thus an especially smooth wiping operation can be achieved if the width of the extension, as measured in the longitudinal direction of the wiper blade, is matched to the width of the groove. In the case of a wiper arm which, at least in the region of the pivot pin, has a U-shaped cross section, the U-legs of which are directed toward the windshield, and [sic] simple fastening of the pivot pin can be achieved owing to the fact that the pivot pin passes through the U-leg adjacent to the wiper blade in a recess and is fastened to the other U-leg. Advantages for the stockkeeping of the wiper device may be obtained owing to the fact that a separate connection piece which has both the pivot pin and the securing means for the wiper blade is fastened to the free end of the wiper arm or the pivoted lever. If the wiper arm or its pivoted lever is designed as an injection molding, the pivot pin can be connected in a simple manner to the wiper arm or to the pivoted lever by the pivot pin being formed with one end in the wiper arm. Further advantageous developments and configurations of the invention are specified in the following description of exemplary embodiments shown in the associated drawing. Drawing In the drawing: figure 1 shows a side view of a wiper blade belonging to the wiper device according to the invention, figure 2 shows a plan view of the wiper device with the wiper blade according to figure 1, figure 3 shows perspective representations of a detail, designated by III in figure 2, of the wiper device, depicted on an enlarged scale, figure 4 shows a section along line IV-IV through the wiper arm according to figure 3, depicted in an appropriately rotated manner, figure 5 shows a section along line V-V through the wiper arm according to figure 3, depicted in an appropriately rotated manner, figure 6 shows a plan view of the free end, produced as an injection molding, of a possible design of the wiper arm, figure 7 shows a section along line VII-VII through the wiper arm according to figure 6, represented in an appropriately rotated manner, figure 8 shows a section along line VIII-VIII through the wiper arm according to figure 6, represented in an appropriately rotated manner, figure 9 shows a partial representation (not to scale) of the wiper arm connected to a wiper blade, the wiper arm together with the wiper blade being swung into an assembly position away from the windshield, figure 10 shows the arrangement according to figure 9 in the operating position, figure 11 shows a section along line XI-XI through the wiper device according to figure 10 in enlarged representation, and figure 12 shows a section along line XII-XII through the wiper device according to figure 10 in enlarged representation. Description of the exemplary embodiments A driven wiper arm 12 guided on a motor-vehicle body belong [sic] to a wiper device 10 (shown in figure 2) for windshields of motor vehicles, on the free end of which wiper arm a wiper blade 14 is articulated. The articulated connection between the wiper arm 12 and the wiper blade 14 is effected by an appropriately designed connection device 16. The wiper arm 12 and thus also the wiper blade 14 are loaded in the direction of arrow 18 relative to the windshield 20 (indicated in figure 1 by dot-dash line) of a motor vehicle, with which windshield an elongated, elastomeric wiper strip 22 belonging to the wiper blade 14 can be brought into contact. In this operating position which is then achieved, the wiper blade is displaced over the windshield in the direction of double arrow 24 (figure 2) in order to clean the surface 28 of said windshield. However, the wiper blade 14 is shown in figure 1 in a position in which only its two ends touch the windshield 20. The wiper strip 22 of the wiper blade 14, in a parallel manner with respect to the longitudinal axis, is arranged on one band side 25, facing the windshield, of a one-piece, band-shaped supporting element 26. On the other band side 27, facing away from the windshield 20, of the supporting element 26, a wiper-blade-side device part 3 0 belonging to the connection device 16 is fastened to the center section of said supporting element. As can be seen from figure 1, the wiper blade, in its position shown, in which it is still not brought into contact with the windshield 20 over its entire length, is curved to a greater extent than the windshield. Since the greatest curvature of the windshield surface 28 is shown in figure 1, it can clearly be seen that the curvature of the wiper blade 14 bearing with its two ends against the windshield 20 is greater than the maximum windshield curvature. Under the applied pressure (arrow 18), the wiper blade, with its wiper lip 32, comes into contact over its entire length with the windshield surface 28 to be wiped. In the process, a stress builds up in the elastic supporting element 26, this stress providing for proper contact of the wiper strip 22 or of the wiper lip 32 over its entire length with the windshield 20. Since the windshield, which as a rule is curved spherically, does not constitute a segment of a surface of a sphere, the wiper blade 14, relative to the wiper arm 12, must be able to adapt itself continuously to the respective position of the windshield surface during its wiping movement (double arrow 24) . Therefore the connection device 15 [sic] is at the same time designed as an articulated connection between wiper blade 14 and wiper arm 12. Two exemplary embodiments of the connection between wiper blade and wiper arm are to be dealt with in more detail below. It can be seen from figure 3 that the wiper blade 14 has a one-piece, band-shaped supporting element 26. Sitting in the center section (shown here) of the wiper blade is the wiper-blade-side device part, or coupling part 30, by means of which the wiper blade 14 can be connected to the wiper arm 12 in an articulated manner. The device part 30, which in the exemplary embodiment is made of plastic, is firmly connected to the wiper blade or to its supporting element 26. It has a block-shaped section 34 in which a bearing bore 3 6 designed as a blind hole is arranged. The bearing bore 36 is located in the block-shaped section 34 of the coupling part, specifically close to its one longitudinal end. Toward the other longitudinal end, a groove 3 8 running transversely to the longitudinal extent of the wiper blade 14 adjoins the section 34 of the device part 30, this groove 38 being open toward the top side facing away from* the supporting element 26. The end section 40 adjoining the transverse groove 3 8 toward the other end of the device part 30 likewise has a block-like form, but is not so high as the section 26 [sic] having the bearing bore 36. From this it follows that, with respect to the top side 27 of the supporting element 26, the section 34 of the device part 3 0 has the greatest height. This height is provided with the reference numeral 42 in figure 11. The device part 3 0 has its smallest height in the region of the transverse groove 3 8 or the groove root. This dimension has been designated by the reference numeral 4 4 in figure 12. The height of the section 4 0 corresponds in the exemplary embodiment to the height 42 of the section 34. However, it is also perfectly conceivable to retain the height dimension 44 from the groove region over the section 4 0 of the device part 30, so that a step is produced instead of the groove 38. Furthermore, the device part 30 is provided with inclined surfaces 4 6 in the region of its section 4 0 beyond the transverse groove 38. However, the inclined surfaces 4 6 are dimensioned in such a way that side cheeks 48 remain over the entire longitudinal extent of the device part 30 at its two longitudinal sides opposite one another, these side cheeks 48 extending from the section 34 via the transverse groove 3 8 up to the end of the section 40 of the device part 30 (figure 3) . Figure 3 also shows the free, connection-side end of the wiper arm 12, which in this embodiment is designed as a sheet-metal part produced by a forming process. It has a pivoted lever 50, which extends from a bearing point 52 (figure 2) on the motor-vehicle body and has a U-shaped cross section at least over large regions. The U-legs 54 of the pivoted lever 50 are directed toward the windshield 20 to be wiped. Close to its free end remote from the bearing point 52, the pivoted lever has a pivot pin 56, which has a smooth lateral surface and the pivot axis 55 of which extends essentially in the direction of movement of the wiper arm (double arrow 24 in figure 2) . The diameter of the pivot pin 56 is matched to the diameter of the bearing bore 3 6 in the device part 3 0 in such a way as to result in an easy-running fit which as far as possible is free of play and allows the wiper blade 14 to perform an unimpeded swinging movement about the pivot axis 55 of the pivot pin 56. As can also be seen from figure 3, the U-base 58 of the pivoted lever 50 extends with an L-shaped extension 60 beyond one U-leg 54, one L-leg 61 connected to the U-base 58 being oriented transversely to the extent of the pivoted lever 50. The other L-leg 62 is oriented toward the windshield 20, The distance 64 from the free end of the wiper arm 12 or of the pivoted lever 50 to the pivot axis 55 is less than the distance 66 from the free end of the wiper arm or of the pivoted lever 50 to the L-shaped extension 60. When the wiper blade 14 according to figure 3 is to be attached to the connection end of the wiper arm 12 (figure 3), first of all the wiper arm 200 is to be put into a position - swung away from the windshield 20 in the opposite direction to arrow 65 [sic] - which is shown in figure 9. Furthermore, the wiper blade 14 must then assume that position relative to the wiper arm which is shown in figure 9 and in which the L-leg 62 of the L-shaped extension 60 belonging to the wiper arm 12 assumes the position shown in figure 9 relative to the transverse groove 3 8 of the device part 3 0 belonging to the wiper blade 14. Provision is to be made for appropriate matching of the distance of the pivot axis to the two groove side walls, on the one hand, to the distance from the pivot axis to the side edges of one L-leg 61 connected to the pivoted lever 50 of the wiper arm 12. When the assembly position shown in figure 9 between wiper arm 200 and wiper blade 14 has been achieved, the wiper blade 14 can be pushed in the direction of the pivot axis 55 onto the pivot pin 56 of the wiper arm until the side cheek 4 8 having the orifice of the bearing bore 36 comes to bear against the wiper arm or against a shoulder fixed to the wiper arm. In this intermediate assembly position, the wiper blade 14 can be rotated relative to the wiper arm 200 in the direction of arrow 86 (figure 9) in such a way as shown in figure 10. After that, the wiper arm can also be swung back in the direction of arrow 85 (figure 9) and can thus be put into its operating position, in which the wiper blade 14 bears against the surface 28 of the windshield 20 to be wiped (figure 10) . The relative movement between the wiper arm and the wiper blade is therefore possible, since the distance 68 (figure 12) between the inside, facing the wiper arm 12, of the leg 62 is matched to a dimension 70 which is obtained at the wiper blade or, in the exemplary embodiment, at the device part 3 0 as measured in the direction of the pivot axis 55. In this case, the two measuring points need not necessarily be opposite one another. In the exemplary embodiment, one measuring region 72 is formed on the side cheek 4 8 of the device part 30, this measuring region 72 being directly adjacent to the inside of the L-leg 62 when the wiper blade is mounted on the wiper arm. The other measuring region 74, in the exemplary embodiment according to figure 11, is formed by the annular collar 76 of a bearing bush 78, the bore of which performs the bearing function for the pivot pin 56 and which in turn is firmly seated in the device part 30. In this case, the outer end wall 8 0 of the annular collar 76 is regarded as a reference point for the measuring region 74. In the configuration of the device part 3 0 according to figure 3, the corresponding measuring points for the dimension 70 are formed by the two longitudinal sides or side cheeks 48 of the device part 30 itself. It is important that, in the operating position of the wiper device shown in figures 11 and 12, one side cheek 48 of the wiper blade and respectively the measuring regions 72 and 74 of the wiper blade are directly adjacent to and opposite the inside 63 of the L-leg 62 and respectively the measuring region 75, formed on the wiper arm 12, for the distance 68. The L-leg 62 or its inner wall 63 facing the wiper arm, together with the measuring point 75, facing this inner wall, on the wiper arm, forms supporting regions which are arranged at a distance 68 from one another in the wiping direction and are directed toward one another. Lying between these supporting regions 63 and 75 of the wiper arm are fitting regions 72, 74 of the wiper blade, which point away from one another and are formed by the end wall 80 of the annular collar 76 and respectively on the side cheeks 48 of the device part 30. It can be seen from figures 2 and 3 that, as measured in the longitudinal direction of the wiper blade 14, the distance 82 from the bearing bore or the pivot axis 55 across the transverse groove 3 8 up to one end of the wiper blade is greater than the distance 84 from the pivot axis 55 to the other end of the wiper blade. Due to the displaced center of gravity, which is established in this way, toward one end of the wiper blade, a moment is produced when the wiper device 10 is swung away from the windshield 2 0 in the opposite direction to arrow 85 in figure 9, and this moment rotates the wiper blade about the pivot axis 55 in the direction of arrow 86, so that the wiper blade, with the side cheeks 48 of the device part 30, always remains between the securing means 63, 75 of the wiper arm 12 and is thereby secured against unintentional release of the wiper arm. Due to the fact that the operating position of the wiper blade 14 between the securing means of the wiper arm is of necessity predetermined, incorrect assembly is reliably avoided, since otherwise the operating position, which can clearly be seen, between wiper arm and wiper blade cannot be achieved. The arrangement of the bearing bush 7 8 instead of the blind bore 36 according to figure 3 can produce advantages with regard to the matching of the sliding pairs. It may also be mentioned with regard to the configuration according to figures 11 and 12 that the wiper blade there is not provided with a one-piece supporting element but that it consists of two sectional rails 102 which lie in longitudinal grooves 104 of the wiper strip 106. The sectional rails 102 are secured in their longitudinal grooves 104 owing to the fact the device part 3 0 engages like a clip over and under those longitudinal edges of the sectional rails which are remote from one another. Furthermore, figures 4, 5, 11 and 12 show that, in the case of a wiper arm 12 which is produced from sheet metal and is U-shaped in cross section and the U-legs 54 of which are directed toward the windshield 20, the pivot pin 56 passes through in [sic] the U-leg 54 adjacent to the wiper blade 14 in an aperture 108 and is fastened, preferably riveted or welded, to the other U-leg 54. In another embodiment of the wiper arm 12 shown in figures 6 to 10, this wiper arm is provided at its free end with a separate connection piece 202, which is produced by casting or injection molding and has both the pivot pin 204 and the securing means 208 for the wiper blade. In this case, the pivot pin is formed in the free end piece 206, of solid design, of the wiper arm. In this embodiment, it is clear that the L-shaped extension 2 08 is also integrally formed directly on the connection piece 202. The arrangement and configuration of the pivot pin 204 and of the L-shaped extension 208 by themselves and with regard to one another completely corresponds [sic] to the embodiment of the invention explained with reference to figures 3 and 12. To improve the guidance of the wiper blade on the wiper arm and to relieve the load on the bearing means 3 6 and 56 of the wiper arm and the wiper blade, respectively, it may be advantageous if the width, measured in the longitudinal extent of the wiper arm, of one L-leg 61 and the width of the transverse groove 3 8 are suitably matched to one another. A common feature of both exemplary embodiments is that the securing means for the wiper blade 14 are arranged on the wiper arm 12 and interact on that side of the wiper blade which faces away from the latter with a wiper-blade-side stop, which is formed by the inner wall of the other L-leg 62. It is clear that the wiper blade is secured on the pivot pin toward the other side by the wiper arm itself, since the pivot pin is fastened to this wiper arm. WE CLAIM : 1. A wiper device (10) for windshields of motor vehicles, having a driven wiper arm (12) which is guided on the motor vehicle and is movable between reversal positions, and on the free end of which a pivot pin (56) is arranged and is held at one end on said wiper arm (12), the pivot axis (55) of which pivot pin (56) extends transversely to the wiper-arm longitudinal axis and essentially in the direction of movement of the wiper arm, and a wiper blade (14) which can swing about the pivot axis (55) is mounted on the pivot pin, the wiper device having means for securing the wiper blade on the pivot pin (56), characterized in that the securing means (60) are arranged on the wiper arm (12) and interact on that side of the wiper blade (14) which faces away from the latter with a wiper-blade-side stop (62, 63). 2. The wiper device as claimed in claim 1, wherein the wiper blade (14) has a supporting element (26) which is elongated in a band shape, is produced from an elastic material and is intended for a wiper strip (22), which can be brought into contact with the windshield (20) to be wiped, and on whose band surface on an upper side (27) facing away from the windshield a coupling part (30) belonging to a connection device (16) and having the bearing aperture (36) for the pivot pin (56) is arranged. 3. The wiper device as claimed in claim 1 or 2, wherein the securing means (63, 54) of the wiper arm (12) are formed by supporting regions (62, 75) which are formed on the latter, are arranged at a distance from one another in the wiping direction (double arrow 24) and are directed towards one another, and between which fitting regions (48 and 80 resp.) of the wiper blade (14) which point away from one another are arranged. 4. The wiper device as claimed in claim 3, wherein one supporting region (75) is arranged on an operating lever (50) of the wiper arm (12), and in that the pivoted lever has an extension (60) which projects in the direction of the extent of the pivot axis (55) and crosses the wiper blade, and on the free end of which a leg (62) directed toward the windshield is arranged, that side of said leg (62) which faces the pivoted lever forming the other supporting region. 5. The wiper device as claimed in claim 4, wherein the distance (64) from the free end of the wiper arm to the pivot axis is less than the distance (66) from the free end of the wiper arm to the extension (60). 6. The wiper device as claimed in claim 5, wherein the bearing bore (36), as viewed in the longitudinal direction of the wiper blade (14), is arranged in the coupling part (30) close to one end of the latter, and in that the coupling part is lower at least in the region of the extension (60) and with reference to the supporting element (26) than in the region of the bearing bore (38). 7. The wiper device as claimed in claim 6, wherein the coupling part (30), in the region of the extension (60) arranged on the wiper arm, is provided with a groove (38), which is open toward the top side facing away from the supporting element (26) and in which the extension (60) crosses the coupling part (30). 8. The wiper device as claimed in claim 7, wherein as measured in the longitudinal direction of the wiper blade (14), the distance (82) from the bearing bore (36) across the transverse groove (38) up to one end of the wiper blade (14) is greater than to the other end of the wiper blade. 9. The wiper device as claimed in any one of claims 3 to 8, wherein the fitting regions (72, 74) of the wiper blade (14) are formed on the two longitudinal sides (48) of the coupling part (30) opposite one another. 10. The wiper device as claimed in claim 9, wherein the distance (70) between the fitting regions of the wiper blade, as measured in the direction of the pivot axis (55), is matched to the distance (68) between the supporting regions (63, 75) of the wiper arm. 11. The wiper device as claimed in any one of claims 7 to 10, wherein the width of the extension (60), as measured in the longitudinal direction of the wiper blade, is matched to the width of the transverse groove (38). 12. The wiper device as claimed in any one of claims 1 to 11, wherein the wiper arm, at least in the region of the pivot pin (56), has a U-shaped cross section, the U-legs (54) of which are directed toward the windshield (20), and in that the pivot pin (56) passes through the U-leg adjacent to the wiper blade in a recess (108) and is fastened to the other U-leg (54). 13. The wiper device as claimed in any one of claims 1 to 11, wherein at least one section (202) of the wiper arm (200) is designed as an injection molding, and in that the pivot pin (204) is formed with its one end in the wiper arm. 14. The wiper device as claimed in any one of claims 1 to 11, wherein a separate connection piece (202) which has both the pivot pin (204) and the securing means (208) for the wiper blade (14) is fastened to the free end of the wiper arm or the pivoted lever. 15. A wiper device for windshields of motor vehicles, substantially as herein described with reference to the accompanying drawings.

Documents:

in-pct-2001-115-che-abstract.pdf

in-pct-2001-115-che-claims duplicate.pdf

in-pct-2001-115-che-claims original.pdf

in-pct-2001-115-che-correspondence others.pdf

in-pct-2001-115-che-correspondence po.pdf

in-pct-2001-115-che-description complete duplicate.pdf

in-pct-2001-115-che-description complete original.pdf

in-pct-2001-115-che-drawings.pdf

in-pct-2001-115-che-form 1.pdf

in-pct-2001-115-che-form 19.pdf

in-pct-2001-115-che-form 26.pdf

in-pct-2001-115-che-form 3.pdf

in-pct-2001-115-che-form 5.pdf

in-pct-2001-115-che-pct.pdf