Wiper blade for cleaning vehicle windscreens

State of the art

p0001In wiper blades of the kind specified in the preamble of claim 1, the support element over the entire wiping field swept by the wiper blade is designed to ensure a uniform distribution of a connected to the wiper blade wiper outgoing wiper blade contact pressure on the disc. Through a corresponding curvature of the unstressed support element - that is, when the wiper blade is not resting against the window - the ends of the fully applied to the disc in the wiping operation of the wiper blade wiper strip are burdened by the then tensioned supporting element on the disk, even if the radii of curvature of spherically curved vehicle windows change with every wiper blade position. The curvature of the wiper blade must accordingly be somewhat greater than that measured at the window to be wiped in the wiping field greatest curvature. The support element thus replaces the complicated support bracket construction with two disposed in the wiper strip spring rails, as practiced in conventional wiper blades (<patcit id="pcit0001" dnum="DE1505397"><text>DE-1505397</text></patcit>).

p0002The invention relates to a wiper blade according to the preamble of claim 1. In a known wiper blade of this type (<patcit id="pcit0002" dnum="DE29611722A"><text>DE-A-29611722</text></patcit> U), the two spring rails integrally joined by arranged at its two ends transverse webs. As these cross-members must be located in the plane of the spring strips of lying between the facing longitudinal edges enclosed by the spring rails and the transverse webs slot be extended in one end portion thereof so that proper installation of the wiper strip in the slot is possible. However, this mounting extension can vary the spring characteristics of the support element with respect to the aspired wiping result disadvantageous. Also, the manual threading of the wiper strip over this extension into the slot is costly.

p0003A generic wiper blade is known from document <patcit id="pcit0003" dnum="US3626544A"><text>US-A-3626544</text></patcit> known.

ADVANTAGES OF THE INVENTION

p0004In the inventive wiper blade with the characterizing features of claim 1, it is possible the wiper strip from one end of the support member from between the introduce two facing longitudinal edges of the spring rail straight, with their inner, free edge strip dip into the longitudinal grooves of the wiper strip. This simple mounting movement may be performed by an automatic assembly machine without difficulty, whereby a significant cost reduction is achieved. Also, the adverse mounting extension of the slot may be omitted, because the bridge-like transverse webs allow the linear mounting movement of the wiper strip from one support element end.

p0005If the transverse webs are designed as separate components and fixed to the spring rails, there are advantages in the wiper blade manufacturing.

p0006For the connection between the spring rails and the transverse webs, it is advantageous if the crosspieces are secured to the upper band surfaces of the two spring rails.

p0007A stable and durable connection between the spring rails and the transverse webs is achieved by welding of these individual components.

p0008Thus, the wiper blade or its wiper strip to adapt smoothly to the respective curvature of the window during wiper operation, it has proved to be advantageous if the length of the spring rails is greater than the length of the wiper strip, because then by appropriate refinements some advantageous longitudinal movement of the wiper strip against the can be supporting element is ensured.

p0009Bracing for a stable supporting element is achieved if at least one transverse web is arranged at each end portion of the two mutually associated spring rails. Depending on the length of the wiper blade, it is, however, quite conceivable that two spring rails be connected using another bridge-like transverse webs. For short wiper blades it has been found that the arrangement of a single transverse web at each end portion of the support element for obtaining a stable, torsion-free wiper blade is sufficient.

p0010Further stabilization of the support element is achieved if a switch located in the central region of the two spring rails belonging to each other crosspiece is designed as part of a connecting device for connecting the wiper blade to the wiper arm.

p0011In development of the invention, at least one of the two arranged on one of the end of the spring rails cross bars connected one with the center portion, the adjacent thereto face of the wiper strip partially covering attack on. This to wander the wiper strip from the supporting element in the longitudinal direction of the wiper blade is prevented.

p0012In the arrangement of a respective each provided with an abutment cross-members at the two ends of the supporting element with regard to a good adaptation of the wiper strip to the respective window curvature, the distance between the two stops is greater than the length of the wiper strip.

p0013To reduce the risk of injury when handling the wiper is provided with a preferably made of plastic cap according to the invention, each arranged at the end sections of the two spring rails crossbar.

p0014Further advantages during wiping operation of the wiper of the invention result from the fact that the thickness of existing in the wiper strip between the two longitudinal grooves wall or web strip is smaller than the distance between the adjacent longitudinal edges of the two matched spring rails. In conjunction with the longitudinal play of the wiper strip in the support element, this results in a "free swimming" stress-free wiper strip that can adapt without being affected by a clamp during wiper operation the wheel profile continuously.

p0015A particularly advantageous development of the wiper blade is obtained when the along its length a constant sectioned wiper strip one can be placed against the disc, strip-like wiper lip which is connected via a formed by oppositely arranged groove-like constrictions narrow web strip with a held on the support element cover strip and each of the two mutually adjacent inner longitudinal edges of the spring rails is arranged in one of the two groove-like constrictions of the wiper strip. Thus, the overall height of the wiper blade is reduced considerably. Because the width of the wider Einschnürungsnut in one section than the thickness of the spring rails, the wiping lip during wiper operation always tilt in the required towing situation.

p0016It is particularly advantageous if the lateral boundary surfaces of the groove-like constrictions of the web strip diverge to the longitudinal sides of the wiper strip. The spring rails can so with appropriate coordination lead the wiper strip to the web strip and allow the wiper lip simultaneously the necessary tilting movement into the drag position.

p0017A refinement of the invention, seen in cross section that the lateral boundary surface of the groove-like constrictions has a spherical curve. This is a convenient and low-noise rolling this side wall allows to the facing strip surface of the respective spring rail.

p0018This advantage can be further improved, as seen in cross-section when both lateral boundary surfaces of the groove-like constrictions have a spherical profile.

p0019To support an optimal contact of the wiper strip on the window to be wiped, preferably spherically curved disc has in one embodiment of the invention the wiper lip shaped as closed longitudinal channel.

p0020This eliminates the need for special measures to attach a connecting device for a wiper blade moving wiper arm, each of the two spring rail protrudes at least with an average margins from its groove-like constriction, so that the connection device can be attached to the exposed edge strip.

p0021Further advantageous developments and refinements of the invention are set forth in the following description of illustrated in the accompanying drawings embodiments.

drawing

p0022In the drawings <figref idrefs="f0001">figure 1</figref> a side view of a wiper blade according to the invention, <figref idrefs="f0001">figure 2</figref> an extended view of the wiper blade according to <figref idrefs="f0001">figure 1</figref> drawn in scale in perspective, <figref idrefs="f0002">figure 3</figref> one belonging to the wiper blade according to the invention, shortened shown support member in an enlarged, extended, perspective view, <figref idrefs="f0002">figure 4</figref> the sectional area of ​​a section along the line IV-IV in <figref idrefs="f0001">figure 2</figref> in an enlarged representation, <figref idrefs="f0003">figure 5</figref> one in <figref idrefs="f0001">figure 2</figref> V Marked detail in an enlarged view, <figref idrefs="f0003">figure 6</figref> the sectional area of ​​a section under <figref idrefs="f0002">figure 4</figref> through another embodiment of the wiper blade according to the invention, <figref idrefs="f0003">figure 7</figref> a <figref idrefs="f0003">figure 5</figref> corresponding detail of the wiper blade according to <figref idrefs="f0003">Figure 6, Figure 8</figref> the sectional area of ​​a section under the <figref idrefs="f0002">figures 4</figref> and <figref idrefs="f0003">6</figref> through a further embodiment of the inventive wiper blade, <figref idrefs="f0004">figure 9</figref> a schematic representation of the sectional area of ​​a section along the line IX-IX in <figref idrefs="f0001">figure 2</figref> through an inventive wiper blade in an enlarged view and this is placed on the windshield to be wiped surface <figref idrefs="f0004">figure 10</figref> the wiper blade according to <figref idrefs="f0004">figure 9</figref> during wiper operation in a wiping direction and <figref idrefs="f0004">figure 11</figref> the wiper blade according to <figref idrefs="f0004">figure 9</figref> during wiper operation in the other wiping direction.

Description of Embodiments

p0023A in the <figref idrefs="f0001">Figures 1 and 2</figref> shown wiper blade 10 has a band-like elongated, spring-elastic support element 12, on whose underside 13 an elongated, rubber-elastic wiper strip 14 is disposed parallel the longitudinal axis. On the upper side 11 of the bar to be designated as a spring support member 14, the wiper blade part by means of which the wiper blade 10 is in its central portion disposed a connection device 16, in an articulated manner to<figref idrefs="f0001">figure 1</figref> indicated in chained lines, driven wiper arm 18 can be releasably connected. For this purpose, the wiper arm 18 is provided at its free end to the wiper arm part of the connecting device. The wiper arm 18 is in the direction of arrow 20 to the window to be wiped - for example, the windshield of a motor vehicle - loaded, which in surface to be wiped<figref idrefs="f0001">figure 1</figref> is indicated by a dashed line 22nd Since the line to 22 represent the greatest curvature of the window surface is clearly evident that the curvature of its two ends adjacent to the window, still unstressed wiper blade 10 is greater than the maximum curvature (<figref idrefs="f0001">figure 1</figref>). Under the contact pressure (arrow 20), the wiper blade 10 its wiper lip 24 creates over its entire length against the window surface 22nd Here, a voltage builds up in the example made of metal, resilient supporting element 12, which ensures a proper contact of the wiper strip 14 and the wiper lip 24 over its entire length against the window and for a uniform distribution of pressure.

p0024Hereinafter, a first embodiment of the wiper blade 10 on the basis of <figref idrefs="f0002 f0003">Figure 3 to 5</figref> are explained in detail. Out<figref idrefs="f0002">figure 4</figref> It can be seen that the support member 12 of the wiper blade 10 is located at a distance 26 in front of the window to be wiped 22nd Here the arrangement is such that its band surfaces 11 and 13 are located in a plane which extends parallel to the window to be wiped surface 22 substantially. The particularly advantageous construction of the support element 12, in particular from the<figref idrefs="f0002">Figures 3 and 4</figref> visible. It has two lying in a common plane, band-like spring rails 28 and 30, which are aligned parallel to each other. The facing inner longitudinal edges 32 befmden thereby at a distance 34 from each other. At each of the two ends of the spring rails 28, 30 these are connected to each other by a bridge-like crosspiece 36 and 38, respectively; for example welded together. Here each bridge-like crosspiece lies with its end 40 on the top 11 of the support element 12 and at its spring rails 28, 30 at. Each of the two crossbars 36 and 28 has a middle section 42 which is located at a distance 44 from the upper band surface 11 of the spring rails and thus justified their bridge-like shape. Since the longitudinal extension 46 of the central portions 42 is greater than the distance 34 between the mutually facing inner longitudinal edges 32, the two spring rails extend 28 and 30 with inner edge strips 48 in the region of the central portions 42, the edge strip 48 by a distance 44 below the middle portions are arranged 42nd Besides the already mentioned objects of the support element 12 with respect to the contact force distribution that is designed to ensure a proper, stress-free guidance of the wiper strip 14 during wiper operation. Thus, a low-noise wiping operation is ensured.

p0025The wiper strip 14 of this first embodiment has a cross-section of the reference <figref idrefs="f0002">figure 4</figref> should be made clear. She has a head strip 50, with the actual wiping work acquiring wiper lip 24 is connected via a narrow web strip 52nd The arrangement of the web strip 52 allows tilting of the wiper lip 24 in a wiping work promoting drag position which will be explained later. The header 50 is provided on its opposite longitudinal sides with edge-open on these longitudinal sides, longitudinal grooves 54 and 56th The longitudinal grooves 54 and 56 serve to receive the inner edge strips 48 of the spring strips 28 and 30. The depth of the longitudinal grooves 54 and 56 is chosen such that a wall 58 remains between the two longitudinal grooves. The header 50 thus has a base bar 60 and a cover strip 62, both of which are connected to each other through the wall 58th The thickness 64 of the wall 58 is smaller than the distance 34 between the inner longitudinal edges 32 of the spring rails 28, 30 and smaller than the distance between the inner edge of strips 48. The width of the two longitudinal grooves 54 and 56 in the header 50 is to the thickness of the spring rails 28, 30 and their inner edge strips 48 tuned to a stress-free mounting of the wiper strip is ensured on the supporting element 12 when the wiper strip according<figref idrefs="f0002">figure 4</figref> in accordance with the supporting element 12 <figref idrefs="f0002">figure 3</figref> is assembled. Also, since the width 66 of the cover strip 62 is slightly smaller than the also as a bridge length to be referred to the longitudinal extension 46 of the central portion 42 and the thickness 67 is smaller than the distance 44 between the central portion 42 and the upper sides 11 of the spring rails 28, 30 can on their entire longitudinal extension are inserted a constant cross-section having the wiper strip 14 without difficulty in the longitudinal direction in the support element 12 and so connected thereto.

p0026Another special feature of the wiper blade according to the invention is in <figref idrefs="f0003">figure 5</figref> shown. There it is shown that the arranged at one end of the support element crosspiece 70 connected at its the wiper blade end facing side in its central portion with a with him, the adjacent end face 72 at least partially covering stopper 74 is provided to him. The stop 74 is formed by a bent, lobe-like extension of the central portion 42nd If each of the two ends of the wiper blade or each of the two ends supporting member in accordance with a cross piece 70<figref idrefs="f0003">figure 5</figref> is provided, it must be ensured that the distance between the facing inner walls 75 of the stop tab 74 is slightly larger, the length 76 of the wiper strip 14 (<figref idrefs="f0001">figure 2</figref>). This can be achieved in that the length 78 of the support member 12 is slightly greater than the length 76 of the wiper strip 14. The two-sided arrangement of the stops 74, for example, also characterized thus forms an effective protection against creeping out of the wiper strip 14 in the longitudinal direction of its support member 12 during the wiping operation. Of course, the bend at least one of the two stop tabs 74 is made only after the introduction of the wiper strip 14 in the supporting element 12 in such a case.

p0027The arranged in the central portion of the wiper blade 10, part 16 of the connecting device for the wiper arm engages around the respective outer, projecting out of the longitudinal grooves 54 and 56, the outer edge strip 80 of the spring rails 28, 30 respectively of the support element 12. The connection between the part 16 and the supporting element 12 can positive and / or non-positively. With an appropriate length of the wiper blade, it may also be desirable if 36 and 38 more corresponding transverse webs are arranged between the two end-mounted crossbars. To avoid personal injury when handling the wiper blade, in particular by the end user is on the two spring rails 28, 30 and the end-side cross-members 36, 38 is a preferably made of plastic cap 82, preferably arranged snapped, preferably snapped (<figref idrefs="f0001">Figures 1 and 2</figref>).

p0028Further embodiments of the wiper blade according to the invention are in the <figref idrefs="f0003">Figures 6 to 8</figref> shown.

p0029The supporting elements of these embodiments are fully compliant with the already described support elements 12 of the <figref idrefs="f0002 f0003">Figures 3 to 5</figref>So that the reference numerals used for this purpose in these figures can be taken directly. However, the configuration of the wiper strip 100 in this embodiment is basically different from the structure of the wiper strip 14 in the embodiment already described. As especially<figref idrefs="f0003">figure 6</figref> shows, the wiper strip 100, only a wiper lip 101 which is connected via a web strip 102 integrally formed with a cover strip 104th The embodiment described in accordance with the already<figref idrefs="f0002">figures 4</figref> and <figref idrefs="f0003">5</figref> therefore existing base strip 60 is omitted. The inner edge strips 48 of the spring strips 28 and 30 are in groove-like constrictions 106 of the wiper strip 100, which are necessary for the formation of the narrow web strip 102nd Thus, the cover strip 104 formed on the lateral boundary surface 108 of the constriction 106 of the upper band surface 11 of the supporting element 12 is facing. The other lateral boundary surface 110 of the groove-like constriction 106 is thus directly opposite the lower band surface 13 of the support element 12th It is thus seen that each of the two inner longitudinal edges 32 of the two spring rails 28, 30 respectively of the support element 12 is arranged in one of the two groove-like constrictions 106 of the wiper strip 100th Further particular<figref idrefs="f0003">figure 6</figref> seen that the two lateral boundary surfaces 110 of the constrictions 106 of convex design and arranged such that the width dimension of the groove-like constrictions 106 wider, at least over an outer portion than the thickness of the spring rails 28, 30. Thereby, it is possible that the wiper lip 101 can tilt during wiper operation in the desired, advantageous drag position. Also in this embodiment of the wiper blade according to the invention, the width 112 of the web strip 102 is so matched to the spacing 34 between the mutually facing inner longitudinal edges 32 of the spring rails 28, 30 such that an air gap remains between the web strip, and the spring rails. Further, the thickness 114 of the cover strip 104 is here slightly less than the distance 44 between the central portion 42 of the crosspiece 36 and the inner edge of strips 48. Also, the width 116 of the cover strip 104 is slightly less than the longitudinal extent 46 of the central portion 42 of the bridge-like transverse webs 36 . this makes it possible over its entire length a constant cross-section having the wiper strip 100 without introducing obstacles in its longitudinal extent into the support member 112 so that the in<figref idrefs="f0003">figure 6</figref> Mounting position shown is obtained. Also in this embodiment, the plane in which the supporting element 12 extends a distance 26 from the surface 22 of the window to be wiped 22nd

p0030As seen from <figref idrefs="f0003">figure 5</figref> can already be described in this embodiment of the wiper blade according to the invention each of the two bridge-like transverse webs 70 may be provided at its viewed in the longitudinal extent of the wiper blade outer ends with a bent-off stop 74, so that after insertion of the wiper strip 14 in the support member 12 and the Abkröpfen the stop flaps 74 a reliable longitudinal securing the wiper strip 100 is secured in the supporting element 12th It is clear that also in this embodiment the distance between the mutually facing inner walls 75 of the stop tab 74 must be somewhat greater than the length 76 of the wiper strip.

p0031Another embodiment of the wiper blade according to the invention is based on the <figref idrefs="f0003">figure 8</figref> are explained. The embodiment of<figref idrefs="f0003">figure 8</figref> corresponds in its basic design to the construction of the reference to the <figref idrefs="f0003">figure 6</figref> Described embodiment. Derogation from the embodiment<figref idrefs="f0003">figure 6</figref> are, however, not only the lateral boundary surfaces 110 but also the other, formed on the cover strip 104 lateral boundary surfaces of the groove-like constrictions 108 106 is formed spherically in this embodiment. Next, the embodiment according to<figref idrefs="f0003">figure 8</figref> according to the embodiment <figref idrefs="f0003">figure 6</figref> still arranged by the wiper lip 101, through around closed longitudinal channel 118. The arrangement of the longitudinal channel 118 in the wiper lip can take care of themselves or in conjunction with additional longitudinal grooves on a soft, low-noise Umlegeverhalten the wiping lip during wiper operation. Also, the arrangement thereof is not necessarily needed in connection with the convex form of the boundary surfaces 108, 110th

p0032As seen from <figref idrefs="f0001">figures 2</figref> and <figref idrefs="f0002">3</figref> It can be seen, the width of the supporting element 12 over the entire longitudinal extent is the same. However, it is also conceivable that tapers the support element to the end portions of the wiper blade out. In order that the part 16 can be attached to the wiper blade it is sufficient if each spring rail 28, 30 extends at least with a central, outer edge strip 80 from its groove-like constriction so that on that edge strip 80, the part 16 of the connecting device can be attached. Furthermore, it is conceivable that instead of a support element 12 in accordance with<figref idrefs="f0002">figure 3</figref> the two spring rails may be formed as separate components and arranged in the groove-like constrictions of the wiper strip. Ensuring particular axial location 34 can then be taken over by another, not shown components.

p0033The <figref idrefs="f0004">Figures 9 to 11</figref> Show principle-sectional area representations of the wiper blade in accordance with the <figref idrefs="f0003">Figures 6 and 7</figref>Taken along the line IX-IX in <figref idrefs="f0001">figure 2</figref> wherein in <figref idrefs="f0004">figure 9</figref> the wiper blade 10 is placed with its wiper lip 101 only on the surface to be wiped 22nd The wiper strip 100 is held with clearance between the inner longitudinal edges 32 of the two spring rails 28, 30 (see. Also<figref idrefs="f0002">Figures 3 and 4</figref>). Since the length 76 of the wiper strip 100 is also slightly less than the length 78 of the support element 12 or is less than the dimension between the mutually facing inner walls 75 of the abutments 74 at the both ends of the support member 12 results in a so-called "free-floating", stress-free but reliable mounting of the wiper strip 100 in support element 12th

p0034Now, if during wiper operation, the wiper blade 10 when loaded by the contact pressure (arrow 20 in <figref idrefs="f0001">Fig. 1</figref>) In the direction of arrow 122 <figref idrefs="f0004">Fig. 10</figref> is moved over the disk 22, tilts the wiper lip 101 in the web strip 102 in an advantageous drag position wherein the support element 12 of the disc is slightly closer (arrow 123). The tilting movement is limited by the fact that the one lateral boundary surface 110 of supporting a groove-like constriction 106 at the bottom 13 of a spring rail 30th When the wiper blade 10 has reached its reverse position and through the wiper arm 18 in the opposite direction (arrow 124<figref idrefs="f0004">Fig. 11</figref>) Is moved, tilting the wiper lip 101 a from <figref idrefs="f0004">figure 9</figref> apparent intermediate position into its other drag position (<figref idrefs="f0004">Fig. 11</figref>) Wherein the wiper lip 101 with the lateral surface 110 of the other groove-like constriction 106 is supported on the bottom 13 of the other spring rail 28th

p0035When the tow layers of the wiper lip 101 near their reversal points - because of the typically spherical curvature of the windshield 22 - approximates the disc, the spherically shaped limiting surfaces 110 roll noiselessly from the bottoms 13 of the spring rails 28, 30th Accordingly can - if necessary - also the other convex boundary surfaces 108 of the groove-like constrictions 106 roll on the upper sides 11 of the spring rails 28 and 30 respectively.