Exemplary embodiments of the invention are explained in detail making reference to the enclosed drawings. The drawings show:
FIG. 1 A perspective representation of a windshield wiper installation with a fastening device without screws with a receptacle device on the vehicle side according to the prior art;
FIG. 2 A schematic lateral section through an individual fastening in accordance with the invention before assembly;
FIG. 3 A top view of the areas of the wiper installation and the vehicle body prepared for fastening in accordance with the invention, however without a clamp lock;
FIG. 4 A top view in accordance with FIG. 3, however, with a clamp lock that has been inserted, rotated and brought into the locked position;
FIG. 5 A locked fastening in a state in accordance with FIG. 4 in the same representation as FIG. 1;
FIGS. 6 and 7 Schematic representations, both in top views, of the tie bolt by itself and the tie bolt inserted into the tension lever.
FIG. 1 shows a windshield wiper installation for a motor vehicle known from the prior art, which is comprised of a rod-like supporting body 2, which bears a bearing body 3 (molded tube) respectively on both ends. A wiper shaft 4 to accommodate a windshield wiper arm (not shown) is axially secured and rotatably disposed in each bearing body 3. Sitting approximately in the center of the supporting body 2 is the mounting plate 5 [and] a drive device 6, which operates on a connecting rod 7. The ends of the connecting rod 7 are connected in an articulated manner with the oscillating cranks 8 and 9, each of which are in turn rigidly connected to the wiper shafts 4.
The known windshield wiper installation 1 is fastened to a vehicle body 14 by means of a fastening device at points 10, 11, 12 and 13 beneath a windshield (not shown). Currently, the fastening is typically realized at least at one of the points 10 through 13 by means of a screw, while plug pins can be provided at the other points on the wiper installation side. In other embodiments, the windshield wiper installation 1 can also be equipped with two or more bearings 3 for a wiper shaft 4 or other mechanical modifications respectively.
FIG. 2 shows a plate-shaped area 15 of the wiper installation 1 with a through bore 17 and an area 16 of the vehicle body 14 arranged parallel to it with a bore 18 that is approximately congruent to bore 17. A rubber element 19 is placed, in particular inserted, in the contour of the bore 17 as damping, wherein the rubber element 19, as shown, grips around the edge of the area 15 so far on its underside that a surface that is adequate for damping between the adjacent areas 15 and 16 (which are pressed against one another in the subsequent fastening) is made available.
The clamp lock 20 made of plastic that is shown in FIG. 2 is comprised of a tie bolt 21 and a tension lever 22. The tension lever 22 has a cam or eccentric section 23, whose function will be explained in more detail below in connection with FIG. 5, as well as a swivel section 24. The tie bolt 21 has a widened foot portion 25, which typically has a longish shape and extends transverse to the bolt longitudinal axis B. The head portion, not shown here in FIG. 2, of the tie bolt 21 is rotatably disposed on the tension lever 22 so that the tension lever 22, in the embodiment and depiction provided here, can be swiveled counterclockwise around an axis A that runs perpendicular to the plane of the paper. As the arrows indicate, the entire clamp lock 20 is pushed from above through the stacked through bores 17 and 18. Deviating from the embodiment depicted in FIG. 1, the vertical arrangement of the areas 15 and 16 can be interchanged without hesitation. For reasons related to ease of assembly, it is preferred if the rubber element 19 is attached in the through bore 17 of the area 15 on the wiper installation side, which area can be formed on a molded tube (see bearing body 3 in FIG. 1), i.e., if necessary, together with area 15 interchange the position with area 16.
The top view in FIG. 3 depicts an embodiment of the invention with a special shape of the through bores 17 and 18 or of the foot portion 25. The longish shape of the bores 17 and 18 that is somewhat constricted in the middle makes possible a (corresponding adapted) foot portion 25 that fits through the bores, which, on the one hand, has a large bearing surface towards the underside of the area 16 according to FIG. 2, and, on the other hand, however, does not go hand in hand with an undesirably high use of material.
FIG. 4 depicts the state of the fastening after the clamp lock 20, more precisely the foot portion 25 and a portion of the center piece of the tie bolt 21, has been pushed through the matching passage openings 17 and 18, the foot portion 25 (together with the entire clamp lock 20) was then rotated in a position altered by 90°, for example, and finally, the tension lever 24 [sic] was swiveled from its position parallel to the bolt longitudinal axis B by approx. 90°, i.e., around its cam or eccentric section 23 supported on the plate-shaped area 15.
The lateral section in FIG. 5 again shows the locked position of the fastening that is achieved in accordance with FIG. 4. The widened foot portion 25 in this case grips behind the area 16 from the “rear” side while the clamp lock 20 is supported on the “front side” of area 15. The function of the cam or eccentric section 23 that is known per se is based on the fact that, because of the geometric design with the lengths a>b, the swiveling of the tension lever 22 goes hand in hand with a cam stroke, i.e., a displacement of the tie bolt 21, which is utilized to tension the lock 20. The plate-shaped areas 15 and 16 are consequently clamped or squeezed by swiveling the tension lever 22 into the clamping position between the underside of the tension lever 22 and the widened foot portion 25 as shown in FIG. 5.
As FIG. 5 shows, the locking effect brought about by the clamp lock 20 can be further reinforced by a locking nose 27 that projects from the upper side of the area 15 and engages in an appropriate locking receptacle in the swivel section 24.
FIGS. 6 and 7 schematically show a top view of an exemplary embodiment of the intermeshing of the clamp lock's 20 two components, i.e., of the tie bolt 21 and the tension lever 22. FIG. 6 depicts in particular the head portion 26 of the tie bolt 21, which can be embodied to be approximately cylindrical for example. FIG. 7 shows the position of the cylindrical head portion 26 as an axis between the ends of the U-legs, i.e., the cam or eccentric sections 23, of the tension lever 22 that is embodied to be U-shaped.
In the meantime injection tools for plastic components are known, which allow the components of the parts to be injected into one another. In the case of the process of multi-component injection molding that is known per se (also called two-shot or over-molding method), the preliminary injection molding is injected from the first component into a cavity of the mold. This is then supplemented by additional components in subsequent cavities by the releasing of volume, wherein the preliminary injection molding is also transported if necessary. It particular, it is also possible using a method that is sometimes called assembly injection molding to produce movable (vis-à-vis one another), non-detachable connections between two components of a part. In the case of the clamp locks being used for the wiper installation in accordance with the invention, which have a rotatably disposed, i.e., sprayed-on, tension lever 22 arranged on the tie bolt 21, the required full bonding incompatibility of the two components can be advantageously realized by using different plastics for the components and the correspondingly varying shrinkage behavior, or else by correspondingly adapting the injection parameters and injection molding cycle times in order to avoid “bonding” of the components. The advantage of this multi-component injection molding in the context related to the invention is that creating a one-part clamp lock with rotatable components, wherein the assembly process of the components that would otherwise be required is shifted to the injection mold. The use of the one-piece plastic clamp lock 20 in accordance with the invention makes a simply structured and easy-to-install wiper installation fastening possible.
Patent Application
20080022476
