Title of Invention

WIPER BLADE

Abstract

The invention emanates from a hinge-free wiper blade (10) that comprises of a wiper arm (12) with a wiper seal (14), of two resilient bars (30, 32) and a connecting device (22), whereby the resilient bars (30, 32) engage with lateral longitudinal grooves of the wiper arm (12) that are open towards the outside and are encompassed by claw feet (28, 68, 76, 108) of a metal claw (24, 64, 72, 106) of a connecting device (22) from an outer narrow side. It is proposed that the claw feet (28, 68, 76, 108) be curved around the narrow sides of the resilient bars (30, 32) during assembly of the metal claw (24, 64, 72, 106), whereby at least one layer (70) and/or an intermediate layer (48, 84) made of a synthetic material is provided between the claw feet (28, 68, 76, 108) on the one hand and the resilient bars (30, 32) on the other, that are manufactured separately from the wiper arm (12) and are aligned to the claw feet (28, 68, 76, 108) as well as exhibit a high adhesion factor at their surface towards the metal claw (24, 64, 72, 106) and to the resilient bars (30, 32). (Fig. 5)

Full Text

WIPER BLADE Prior Art The invention emanates from a hinge-free wiper blade in accordance with the preamble of Claim 1. A hinge-free wiper blade is established in DE 101 13 680 A1 whose wiper arm is made from an elastomer material and which has a spoiler at its top side. This can be placed directly and be composed from the same material as the wiper arm or can be a separate component from a suitable other synthetic material. The spoiler can serve as a support member of the wiper blade either independently or together with resilient bars that are inserted in lateral longitudinal grooves of the profile of the wiper arm. Caps are placed on to the ends of the wiper blade, whose conducting surfaces run in the longitudinal direction of the wiper blade and connect to the conducting surface of the spoiler with a small passage. With increasing vehicle speed, the air stream presses the wiper blade with augmented force against the windscreen through the conducting surfaces of the spoiler and the end caps when the air stream blows the wiper blade essentially diagonal to the longitudinal direction. A connecting device is affixed in accordance with the so-called "Sidelock System" at the support member in a cut-out of the spoiler in the middle section of the wiper blade in which the wiper arm runs laterally parallel to the wiper blade in the region of the connecting device. A so-called "Overlook System" is also established in which the wiper arm runs above the wiper blade in the region of the connecting device. The connecting device has two claws respectively at its side frames, which laterally surround and hold the resilient bars of the support member. A hinge-free wiper blade is established in DE 198 35 065 A1 that exhibits a wiper arm with a wiper seal and a headpiece. The headpiece is connected in the conventional manner to the wiper seal through a tilting bar that is bordered by two lateral longitudinal grooves. The headpiece has a central longitudinal channel in which a support member, in the form of a flat, oblong resilient bar, is embedded. A connecting device in the form of a metal claw is affixed in the middle section of the headpiece, based on the length extension. The connecting device has a U -shaped profile with a base adjacent to the headpiece and side walls that extend at it in the longitudinal direction of the wiper blade and connect outwards so that the U-shaped profile is open towards that side that is turned away from the wiper arm. The two side walls are connected to one another in their middle section by a joint bolt, which serves to hinge the wiper blade to a wiper arm according to the Top-Lock-System. Two metal lugs that are curved around the headpiece and partially surround the resilient bars at the longitudinal side respectively, release from the side walls respectively in the vicinity of the front sides of the metal claws. The claw feet formed by the lugs are pressed together in a perpendicular manner against the broad side of the resilient bars, till the metal claws sit firmly at the resilient bar and can not be moved. It is, hereby, of advantage if the intermediate layer between the metal claws and the resilient bar, which is formed by the headpiece of the wiper arm in the exemplary embodiments, has a greater friction co-efficient than the metal claws and the resilient bars. This applies, in general, to materials from which wiper arms are manufactured. The embodiments presented show resilient bars as support members, manufactured as a single part from a metal. These can, however, also be basically composed of several single parts. Difficulties during fixing the position of the resilient bars, when two essentially parallel running resilient bars are provided, can, however, be expected during assembly of the metal claws. Furthermore, a wiper blade with a gimbal system is established in DE 43 20 637 A1. A resilient bar is provided in a central longitudinal channel of the wiper arm. This bar has partial broadenings at its end section, which distend the longitudinal channel outwards to resemble warts, so that the resilient bars are secured in the longitudinal direction, particularly when a holding claw of a gimbal sits between two wart-like elevations. Advantages of the Invention In accordance with the invention, the claw feet are curved around the narrow side of the resilient bars when the metal claws are being assembled. At least one layer and/or one intermediate layer made from a synthetic material is/are thereby provided between the claw feet on the one side and the resilient bars on the other, which are manufactured separate from the wiper arm and are customised to the claw feet as well as exhibit a high adhesion factor at their surface facing towards the metal claws and the resilient bars. As a result of the measures in accordance with the invention, the metal claws lend themselves to easy assembly without any additional welding or pasting even in the case of wiper blades with two resilient bars. The resilient bars can, thereby, be grasped by a device and held at the required distance by a distance device. Since the intermediate layer is manufactured separately from the wiper arm and is assigned and customised to the claw feet, the same can be easily placed on the resilient bars before the wiper arm is assembled. The metal claws of the connecting device can thus first be fixed onto the resilient bars and the wiper arm can subsequently be pushed between the resilient bars. The synthetic material is selected in such a manner that it exhibits the required adhesive behaviour at its surface on the one hand and has a sufficient firmness on the other in order to withstand high tensions in the region of the claw feet. There is, thereby, the possibility that the base material of the intermediate layer acquires the required surface properties through suitable surface treatment or coating. It is, furthermore, appropriate that the claw feet compress the layer or the intermediate layer against the resilient bars. This can happen by the claw feet getting compressed perpendicular to the broad sides of the resilient bars or through a crossing over of a side piece of the claw feet of through lateral compression. The metal claw can exhibit a broad claw foot at each side of the wiper blade or two narrower claw feet that are distanced from one another in the longitudinal direction of the wiper blade and are, as a rule, located in area of the front sides of the metal claws. The length of the intermediate layers is appropriately adjusted to the breadth of the claw feet. If several claw feet are provided at the longitudinal side of the wiper blade, an intermediate layer can also extend over two or more claw feet. The intermediate layer is advantageously manufactured from an l-shaped, Z-shaped or U-shaped extrusion that is cut to the desired length. When in the assembled state, the l-shaped and/or Z-shaped profile lies at the inner longitudinal edge of the allocated claw foot with an angled side piece. The U-shaped extrusion is pushed between the side pieces of the claw feet towards the resilient bars with its open side. In another design of the invention, the intermediate layer is formed at least at its inner surface by coating the claw feet. A synthetic material with the same properties is used, in the process, for the intermediate layer. The metal claws are advantageously covered towards the outside by a cap made of a synthetic material whose outer contours are aligned to the contour of the adjacent spoiler so that this connects without any tiers to the synthetic cap in an optically and fiuidly harmonious manner. The join gap between the spoiler and the synthetic cap is covered in each case by a projecting end at the spoiler and at the synthetic cap, whereby the projecting ends overlap each other. From the point of function, it is immaterial which of the projecting ends lies at the outer side of the profile. The metal claw is advantageously moulded in the synthetic caps and supports itself with internal mating surfaces on the upper broad sides of the resilient bars in that the mating surfaces project a bit towards the resilient bars, relative to the upper side pieces of the claw foot. The mating surfaces made from a synthetic material substitute a corresponding intermediate layer on this side. End caps are, as a rule, mounted and affixed at the ends of the resilient bars. The slits between the end cap and the spoiler are also covered in each case by a projecting end at the end cap and the spoiler respectively. It is, thereby, possible to locate the spoiler on the resilient bars between the end cap and the synthetic cap and/or the metal claw in such a manner that it can be moved axially, so that the flexibility of the wiper blade is influenced only to a small extent by the spoiler in the critical regions. Instead of the intermediate layers or in addition to the intermediate layers, the resilient bars can be secured, relative to the metal claws in the longitudinal direction, by protuberances which lie between two adjacent claw feet and overlap the inner contour of the claw foot upwards, downwards and/or sideways. In order to stabilise the claw feet against one another, the same are appropriately connected to one another by a bridge which is located in an advantageous manner at the inner side of the protuberances. In accordance with a design of the invention, the protuberance exhibits at least two elevations. It is, thereby, possible to push the elevations close to the claw foot without the individual elevation having to be relatively large. Drawing Other advantages emanate from the following description of the drawings in which exemplary embodiments of the invention are presented. The drawing, description and claims contain several features in combination. The expert will be able to appropriately consider the features individually too and combine same in other expedient combinations. Figure 1 presents a perspective view of an assembled wiper blade fromabove; Figure 2 is a perspective view of a partially assembled connecting device according to Figure 1; Figure 3 is an enlargement of the connecting device according to Figure 1; Figure 4 presents a perspective view from below of a connecting device without a support member; Figure 5 is a perspective view from below of a connecting device with asupport member; Figure 6 is a variant to a metal claw according to Figure 2; Figure 7 is a variant to a metal claw according to Figure 2; Figure 8 is a partial view of a metal claw according to Figure 7 in thelongitudinal direction, whose claw foot compresses the intermediate layer perpendicular to the broad side of the resilient bars; Figure 9 presents a partial view of a metal claw according to Figure 7 in the longitudinal direction, whose claw foot compresses the intermediate layer by crossing over a claw side piece; Figure 10 is a partial view of a metal claw according to Figure 7 in the longitudinal direction, whose claw foot compresses the intermediate layer through lateral compression; Figure 11 is a perspective illustration of an end cap from below; Figure 12 is a perspective illustration from above of an end cap according to Figure 11; Figure 13 presents a perspective illustration of an end of an assembled wiper blade; Figure 14 is a perspective partial illustration of a resilient bar with a protuberance and a metal claw and Figures 15 are variants of the design according to Figure 14 to 17 Description of the Exemplary Embodiments A hinge-free wiper blade 10 essentially has a wiper arm 12 with a wiper seal 14 and spoilers 16 to which end caps 18 and 20 are attached in the direction towards the ends. A connecting device 22, through which the wiper blade 10 can be connected in an articulated manner to a wiper arm that is not illustrated, is provided in the central section of the wiper blade 10. The connecting device 22 has a metal claw 24 (Fig. 2) and a synthetic cap 46 (Fig. 3) that are clipped on to the metal claw 24 or on to the resilient bar 30, 32. The resilient bars 30, 32 form a support member for the wiper blade 10. They are curved in such a manner that the wiper blade 10 exhibits an essentially greater curvature in an unloaded state than a resilient bar for which it is intended. If the wiper blade 10 is pressed by the wiper arm against the vehicle's windscreen, a pressure distribution that is suited for the wiping procedure results over the length of the wiper blade 10. The metal claw 24 is formed from a metal strip that is folded at 180 degrees in the central part, whereby the fold runs in the longitudinal direction of the wiper blade 10 and the metal walls lie adjacent to one another in the area of the fold. The free ends of the metal strip are curved towards the outside and cover the upper side of the resilient bars 30 and 32 and form a head space 38 for a headpiece 34 of the wiper arm 12. During assembly, the parts of the metal strip that project laterally over the resilient bars 30, 32 towards the wiper arm 12 are angled twice so that the claw foot 28 is formed with an upper side piece 30, a side frame 44 and a lower side piece 42 respectively. The lower side piece 42 surrounds the resilient bars 30, 32 from below (Fig. 5) and is pressed against the upper side piece 40 so that the resilient bars (30, 32) are clamped between the side pieces 40, 42. An intermediate layer 48, made from a synthetic material, whose friction coefficient to the resilient bars 30, 32 is greater than that of the material of the metal claws 24, is affixed between the claw feet 28 and the resilient bars 30, 32 (Fig. 4). The synthetic material must, however, also be suited to absorb the very high tensions and surface pressures in the region of the claw feet 28. The claw feet 28 can be dimensioned to be sufficiently large in the longitudinal direction, whereby the contact surfaces expand and the surface pressures reduce therewith. The resilient bars 30, 32 are fixed at a pre-determined distance against one another by a distance device 58 during folding over of the claw feet 28 and during the press procedure, approximately perpendicular to the broader surfaces of the resilient bars 30, 32. The intermediate layer 48 is thereby compressed a little against the resilient bars 30, 32. A gap 56 into which the wiper arm 12 is later inserted, is formed between the resilient bars 30, 32, whereby the headpiece 34 lies on that side of the resilient bars 30, 32 that faces the connecting device 22. There is also the possibility of pressing the claw feet 28, 76 against the resilient bars 30, 32 through a crossing over of its lower side pieces 42 (Fig. 9) or through lateral compression of the claw feet 76 (Fig. 10). In the design according to Fig. 4, the metal claw 24 is moulded into the synthetic cap 46 but the metal parts of the claw feet 28 nevertheless remain free so that they can be folded back during the process of subsequent assembly. The synthetic cap 46 with the metai claw 24 is placed on the resilient bars 30, 32 (Fig. 5), whereby guide rails 60 of the synthetic cap 46 grasp the resilient bars 30, 32 from below. The synthetic cap 46 supports itself on the upper side of the resilient bars 30, 32 through mating surfaces 50 at the resilient bars 30, 32. The mating surfaces 50 project a little relative to the upper side piece 40 of the claw foot 28 so that no metal contact is present between the claw foot 28 and the resilient bars 30, 32 at this side. When folding back the lower side piece 42 of the claw foot 28, an intermediate layer 48 made from a synthetic material, is inserted between the lower side piece 42 and the allocated resilient bar. Its length corresponds to the breadth of the claw foot 28, The layer 48 is appropriately cut from an extrusion with an l-shaped or a Z-shaped cross-sectional profile. A side piece of the extrusion lies against the inner edge of the claw foot 28 (Fig. 4 and 5). The metal claw 24 is provided for articulated connection to the wiper arm in accordance with the so-called "Sidelock Principle". It, thus, has a bearing bore 26 that runs co-axial to the bearing opening 62 of the synthetic cap 46. The metal claw 64 with a bearing bore 66 has claw feet 68 that are coated with a layer 70 of synthetic material at least at their inner surfaces. The synthetic material of the layer 70 has the same properties as the synthetic material of the intermediate layer 48 and adheres firmly to the metal parts so that the layer 70 does not loosen when folding the claw feet 68. The metal claw 72, according to the model corresponding to Figure 7, is designed for connecting same to the wiper arm in accordance with the so-called "Overlock Principle". It thus has a bearing pin 74 in its centrepiece. Furthermore, it differentiates itself from the metal claw 24 in that it has two claw feet 76 respectively on each side of the wiper blade 10, to which an intermediate layer 84 made from a synthetic material is allocated. This layer extends between the outer front sides 78 of the claw feet 76 and has a U-form extrusion. The metal feet 76 are formed from metal parts of the metal claw 72 by curving them around the outer longitudinal side of the resilient bars 30, 32 and subsequently pressing them against one another in contact direction 90. The intermediate layer 84 and the layer 70 respectively thereby yield elastically to a small extent. In order to facilitate the bending procedure and in order to avoid cracks in the channel, the default bending points 80 in the channel of the claw foot 76 are provided with a rounded cross-section. Another default bending point 82 is located approximately in the centre of the side pieces through which a controlled moulding of a claw foot 76 is ensured. The end caps 18, 20 are assembled and affixed at the ends of the resilient bars 30, 32 after installing the wiper arm 12 e.g., by pasting, clipping, welding or something similar. For this purpose, the resilient bars 30, 32 have guide profiles 92 in whose guide slot 94, the resilient bars 30, 32 are inserted. A cotter-shaped projection 96 at the closed end of the end caps 18, 20 reaches into the gap 56 and presses the resilient bars 30, 32 apart. The lateral guide profiles 92 can project opposite the front wall 98 towards the spoilers and exhibit a hole 100 in the protrusion, at right angles to the guide slot 94. The hole 100 can serve to pin the end caps 18, 20 to the resilient bars 30, 32. Towards spoiler 16, the end caps 18, 20 have the same external profile as the spoilers 16 so that they, just like the synthetic cap 46, connect to the spoiler 16 without any tiers. The join gaps between the spoiler 16 and the synthetic cap 46 are covered by projections 52 at the spoilers and projections 54 at the synthetic cap 46 that overlap one another. It is, thereby, immaterial whether the projection 52, 54 is located towards the outside. A join gap between the end caps 18, 20 and the spoilers 16 is, likewise, bridged by projections 102 at the end caps 18, 20 and projections 104 at the spoiler 16 in the same manner. Thereby, projections 104 at spoilers 16 can cover the projections of the guide profile 92 with holes 100, towards the outside. Projections 102, 104 enable axial moving of the spoiler 16 between the end caps 18, 20 on the one hand and of the synthetic cap 46 on the other. The resilient bar 30 according to the designs in accordance with Figs. 14 and 15 exhibit protuberances 110, 112, 114 and 116 that lie between two adjacent claw feet 108 of a metal claw 106 in the region of the outer longitudinal sides of the resilient bars 30, 32. The design according to Fig. 14 thereby displays a protuberance 110 upwards towards the centrepiece of the metal claw 106. Free side pieces of the claw feet 108 are connected to one another by a bridge 118 at the lower side of the resilient bar 30. Protuberance 112 according to Fig. 15 extends sideways and upwards while protuberance 114 according to Fig. 16 extends laterally only. Projection 116 has two elevations in the longitudinal direction so that the side surfaces of the resilient bar 30 runs in an undulating manner. Claims 1. Wiper blade (10) that is composed of a wiper arm (12) with a wiper seal (14), of two resilient bars (30, 32) and a connecting device (22), whereby the resilient bars (30, 32) engage with lateral longitudinal grooves of the wiper arm (12) that are open towards the outside and are encompassed by claw feet (28, 68, 76, 108) of a metal claw (24, 64, 72, 106) of a connecting device (22) from an outer narrow side, characterised in that, the claw feet (28, 68, 76, 108) are curved around the narrow sides of the resilient bars (30, 32) during assembly of the metal claw (24, 64, 72, 106), whereby at least one layer (70) and/or an intermediate layer (48, 84) made of a synthetic material is/are provided between the claw feet (28, 68, 76, 108) on the one hand and the resilient bars (30, 32) on the other, that are manufactured separately from the wiper arm (12) and aligned to the claw feet (28, 68, 76, 108) as well as exhibit a high adhesion factor at their surface towards the metal claws (24, 64, 72, 106) and towards the resilient bars (30, 32). 2. Wiper blade (10) according to Claim 1, characterised in that, the claw feet (28, 68, 76, 108), the layer (70) or the intermediate layer (48, 84) are compressed against the resilient bars (30, 32). 3. Wiper blade (10) according to Claim 1 or 2, characterised in that, the intermediate layer (48) exhibits an i-shaped or Z-shaped cross- sectional profile and abuts an angled partition at an inner longitudinal edge of the allocated claw foot (28). 4. Wiper blade (10) according to Claim 1 or 2, characterised in that, the intermediate layer (84) is an extrusion that is U-shaped in cross- section and open towards the resilient bars (30, 32) and whose length is aligned to the breadth of a claw foot (28) or to the distance of the outer front surfaces (78) of two adjacent claw feet (76). 5. Wiper blade (10) according to Claim 1 or 2, characterised in that, the claw feet (68) are coated with a layer (70) of synthetic material at least at their inner surfaces. 6. Wiper blade (10) according to one of the previous Claims, characterised in that, the metal claw (24) is moulded in a synthetic cap (46) that supports itself with mating surfaces (50) at the upper broad sides of the resilient bars (30, 32), in that the mating surfaces (50) project towards the resilient bars (30, 32) relative to the upper side piece (40) of the claw foot (28). 7. Wiper blade (10) according to one of the preceding Claims with a spoiler (16) each at both front sides of a synthetic cap (46), characterised in that, the synthetic cap (46) has the same outer cross- sectional contour as the spoiler (16) in the direction towards the spoilers (16) and overlaps a projection (52) with a projection (54) at the spoilers (16) in an axially moveable manner. 8. Wiper blade (10) according to Claim 7, with a spoiler (16) each at both front sides of the synthetic cap (46) and end caps (18, 20), characterised in that, the spoilers (16) on the resilient bars (30, 32) between the connecting device (22) and the end caps (18, 20) are located to be axially moveable, whereby the end caps (18, 20) are affixed onto the resilient bars (30, 32) and exhibit the same outer cross-sectional contour as the spoilers (16) towards the spoilers (16) and overlap projections (104) at the front sides of the spoiler (16) with projections (102) at its front sides (98). 9. Wiper blade (10) according to the preamble of Claim 1, characterised in that, the metal ciaw (106) exhibits two claws (108) at at least one outer side of a resilient bar (30, 32) between which the resilient bars (30, 32) exhibit a protuberance (110, 112, 114, 116) that overlaps the claw feet (108) upwards, downwards and/or laterally. 10. Wiper blade (10) according to Claim 9, characterised in that, the claw feet (108) that are together allocated to an external side, are connected to one another by a bridge (118). 11. Wiper blade (10) according to Claim 9 or 10, characterised in that, the protuberance (116) exhibits at least two elevations. 12. Wiper blade (10) according to one of the preceding claims, characterised in that, the ciaw feet (28, 68, 76, 108) exhibit a default bending point (80) at at least one of their inner channels. 13. Wiper blade (10) according to Claim 12, characterised in that, the claw feet (28, 68, 76, 108) have another default bending point (82) between their inner channels. 14. Process for manufacture of a wiper blade (10) according to one of the preceding claims, characterised in that, the metal claws (24, 64, 106) are first mounted on to the resilient bars (30, 32), whereby a distance device (58) maintains distance while assembling the resilient bars (30, 32), that the wiper arm (12) is thereafter inserted between the resilient bars (30, 32) and the spoiler (16) and the end caps (18, 20) are

Documents:

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3872-CHENP-2006 AMENDED PAGES OF SPECIFICATION 26-11-2012.pdf

3872-CHENP-2006 AMENDED CLAIMS 26-11-2012.pdf

3872-CHENP-2006 FORM-3 26-11-2012.pdf

3872-CHENP-2006 OTHER PATENT DOCUMENT 26-11-2012.pdf

3872-CHENP-2006 POWER OF ATTORNEY 26-11-2012.pdf

3872-CHENP-2006 EXAMINATION REPORT REPLY RECEIVED 26-11-2012.pdf

3872-CHENP-2006 CORRESPONDENCE OTHERS 18-07-2012.pdf

3872-CHENP-2006 FORM-18.pdf

3872-CHENP-2006 CORRESPONDENCE OTHERS.pdf

3872-CHENP-2006 FORM 18.pdf

3872-chenp-2006-abstract.pdf

3872-chenp-2006-claims.pdf

3872-chenp-2006-correspondnece-others.pdf

3872-chenp-2006-description(complete).pdf

3872-chenp-2006-drawings.pdf

3872-chenp-2006-form 1.pdf

3872-chenp-2006-form 26.pdf

3872-chenp-2006-form 3.pdf

3872-chenp-2006-form 5.pdf

3872-chenp-2006-pct.pdf