GB2030447A

GB2030447A - Windscreen wiper blade harness

Info

Publication number: GB2030447A
Application number: GB7932677A
Authority: GB
Original assignee: SWF Spezialfabrik fuer Autozubehoer Gustav Rau GmbH
Current assignee: SWF Auto Electric GmbH
Priority date: 1978-09-28
Filing date: 1979-09-20
Publication date: 1980-04-10
Also published as: BR7906081A; DE2842132C2; GB2030447B; DE2842132A1; JPS60114056U; JPS5547936A

Abstract

A windscreen wiper blade harness comprises yokes 1, 3, 4, 7, 8 articulated to and overlapping each other such that the width of the yoke assembly is substantially constant over the majority of its length. The relatively low height of the blade assembly is of aerodynamic benefit. Lifting of the blade assembly by airflow may be prevented by suitable shaping of the yoke surfaces. <IMAGE>

Description

SPECIFICATION Windscreen wiper blade The invention relates to a windscreen wiper blade, for use particularly on motor vehicles, comprising a supporting yoke system having a pyramidal construction with governing and subordinate yokes by which a wiper element consisting of resilient material is held and the contact pressure is distributed to the wiper element, the various yokes of the yoke system being laterally articulated to each other.

Such wiper blades have a low overall height with which many favourably characteristics are associated. Because the distance between the suspension point of the wiper arm and the windscreen is only small only a small pitching moment appears which tends to tilt the wiper blade. The cleaning efficiency of a windscreen wiper is favourable affected by a wiper blade which is arranged nearly vertically with respect to the windscreen. As far as wiper blades which are rested below the windscreen in the so-called submerged parking position are concerned a low construction makes it possible to provide a relatively small opening in the vehicle body.

By means of the lateral articulation of the yokes it is prevented that, in the winter, ice and snow becomes fixed between the yokes. Thus also in the winter the yokes are fully movable towards each other and thereby ensure the adaptability of the wiper blade to the curvature of the windscreen.

Indeed a flat construction of a wiper blade also has the effect that the tendency of the wiper blade to be removed from the windscreen by the air stream, in comparison to yokes placed over each other, is diminished. The wiper blades with laterally articulated yokes known from German Specification DE OS 22 52 660 and US patent 3 168, however, offer so many possibilities of attack by an air stream that the lifting forces on the wiper blade still have a noticeable effect on the wiping efficiency of the windscreen wiper.

According to the present invention there is provided a windscreen wiper blade comprising a supporting yoke system having a pyramidal construction with governing and subordinate yokes by which a wiper element consisting of a resilient material is held and the contact pressure is distributed to the wiper element, the various yokes of the yoke system being laterally articulated to each other, and wherein at least one of the yokes has portions of different widths, and wherein the yokes are arranged in overlapping relationships such that the width of the yoke system is substantially constant over the majority of its length.

An embodiment of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a side view of a wiper blade, according to the present invention, having a central yoke, two intermediate yokes and two clawed yokes; Figure 2 is a top view of the wiper blade of Figure 1; Figure 3 is a section, vertical to the longitudinal direction, taken along line Ill-Ill of Figure 1; Figure 4 is a section taken along line IV-IV of Figure 1,and Figure 5 is a section taken along line V-V of Figure 1.

The embodiment shown of wiper blade shown in the drawings substantially consists of a central yoke 1 with a recess or aperture 2 for a wiper arm (not shown), two intermediate yokes 3 and 4 which at one end 5 each have a claw 6, two clawed yokes 7 and 8 which are laterally articulated on the other end 9 of the intermediate yokes 3 and 4, and a wiper rubber 10. The clawed yokes 7 and 8 have two claws 6 each.

All claws 6 embrace the wiper rubber 10, so that a connection between the yoke system and wiper rubber exists. The entire yoke system of the wiper blade is made of a plastics material.

In Figure 1 the web 11 can especially be well recognized in addition to the construction of the wiper blade. The web 11 together with the web 12 (Figures 2 and 3) defines the recess 2 for the wiper arm (not shown). The web 11 is declined diagonally to one side, so that no parts freely projecting upwards exist. The inclined portion 13 thereby extends from one end of the recess 2 up to approximately the centre of this recess. There the two webs 11 and 12 are connected by a transverse pin 14 serving for fastening of the wiper arm.

From Figure 2 furthermore is clearly to be seen how the individual yokes of the wiper blade engage.

The central yoke 1 and the intermediate yokes 3 and 4 are built up of portions with different widths. From the end 9, to which the clawed yokes 7 and 8 are articulated, the intermediate yokes are narrow up to the ends 15 of the clawed yokes 7 and 8. Widened portions 17 are adjacent to narrow portions 16 of the intermediate yokes, the portions 17 are of such a width as to extend up to the front (outermost) side of the clawed yokes 7 and 8.

The space, on the one hand between the intermediate yoke 3 and the clawed yoke 7, and on the other hand the intermediate yoke 4 and the clawed yoke 8, is filled by widened portions of the central yoke 1.

The parts 18 are located in spaces equivalent to those occupied by the portions 16 of the intermediate yokes 3 a nd 4. At the end 19 of the clawed yokes 7 and 8 the central yoke widens to portion 20 which also extends up to the front (outermost) edge of the clawed yokes and intermediate yokes. In the portion 20 is the recess 2 for the wiper arm. Thereby it is avoided that the central yoke 1 has to be widened backwards in its middle area in order to arrange the recess 2 there. The surface 21 (Figure 3) of the portion 20 is shaped as a spoiler surface.

The cross sections of Figures 4 and Son the one hand shown the shovel-like design of the yokes and their assembly into each other, and also a locking device by which the yokes are articulated to one another. In Figure 4 the narrow portion 22 of the central yoke 1 is to be seen. On it the narrow portion 16 of the intermediate yoke 3 is located which is locked with the clawed yoke 7. The wiper rubber 10 is also shown in the drawings. All parts are occupying the position which they have when they are rested upon a plane surface.

In the position shown, the surface 23 of the clawed yoke 7 and the surface 24 of the intermediate yoke 3 together form a spoiler. The clawed yoke 7 with a cylindrical stud 25 having an annular groove 26 and a bore 27 engages into the opening 28 of the intermediate yoke 3 with the locking strip 29. The bore 27 provides a certain elasticity of the stud, so that the yokes can easily be mounted on each other.

The two yokes can indeed rotate round an axis through the centre of the stud 25, but axial motion towards each other is excluded by the locking.

The central yoke 1 and the intermediate yoke 3 shown in cross-sectional view in Figure 5 are locked with one another in the same manner as the clawed yokes 7 and intermediate yokes 3 are articulated on each other as shown by Figure 4.

From Figure 5, however, it is clearly to be seen how the intermediate yoke 3 in its wide portion 17 is shaped. The spoiler, which in Figure 4 is formed by the faces 23 and 24, thus by the clawed yoke 7 and by the intermediate yoke 3, in Figure 5 is defined solely by the face 30 of the intermediate yoke 3. The shape, however, is the same in both cases.

In the symmetrical version of a wiper blade which is shown in Figures 1 and 2 it is a matter of face that cross-sections corresponding to Figure 4 and 5 are also valid for the yokes 1,4 and 8 respectively for the yokes 1 and 4. Thereby it becomes clear that by the invention a wiper blade is created which distinguishes itself by a low construction and has all advantages connected with that and for which without additional parts has a shape which was found to favourably react against lifting tendencies.

In a wiper blade shown the spaces between the yokes are nearly completely filled by the widened portions of individual yokes so that the width of the yoke system is substantially constant over the majority of its length. In spite of the fact that the yokes are arranged beside each other all yokes project with one face as far as to one side of the wiper blade. Thereby they form a nearly straight face on the wiper blade, so that an air stream cannot be kept between the individual yoke and create a lifting.

Above all, as it mostly is the case, if it meets the wiper blade diagonally it has only a few possibilities of attack.

By forming some of the yoke surface as spoilers the possibility of attack of the air stream is restricted as the spoilers increase the pressure which presses the wiper blade on the windscreen. The entire spoiler surface is composed of portions of the individual yokes which in the embodiment described are formed in such a way that in a particular area of curvature a nearly uniform surface is created. It is especially favourable, if the spoiler surface is formed like a shovel. The air stream rises on this shovel, so that a force component is created in a vertical direction with respect to the windscreen.

Whilst itwould be imaginable to eliminate the spaces, in known wiper blades with laterally articulated yokes, appearing between the yokes in longitudinal direction of the wiper blade by making the yokes elongated along their claws. Such a design has, however, disadvantages with respect to the wiper blade according to the invention as well as proper functioning with differently curved windscreens is concerned and also with regard to the stylistic appearance. Therefore a wiper blade according to the invention has to be preferred to this possibility.

The wiper blade according to the invention can be produced in a material saving manner, if yokes belonging to a governing group with their additional portions are located in the elongation of yokes of subordinate groups. There one group of yokes is governing another, if yokes of the first group are carrying those of the further group. So for instance the yoke which is connected to the wiper arm and, if only one yoke of this type is existing, forms the first group alone and governs all other yokes.

The wiper blade according to the invention enables a low construction to be achieved and facilitates and cheapens the mounting of the yokes on each other. Above all the locking saves expensive screw connection or costly riveting of the pivot pins, the application of which would even be made more difficult by the shape of the yokes.

Claims

1. A windscreen wiper blade comprising a supporting yoke system having a pyramidal construction with governing and subordinate yokes by which a wiper element consisting of a resilient material is held and the contact pressure is distributed to the wiper element, the various yokes of the yoke system being laterally articulated to each other, and wherein at least one of the yokes has portions of different widths, and wherein the yokes are arranged in overlapping relationships such that the width of the yoke system is substantially constant over the majority of its length.

2. A windscreen wiper blade as claimed in claim 1, wherein portions of the outermost surfaces of the yokes are formed as spoiler surfaces.

3. A windscreen wiper blade as claimed in claim 2, wherein, at least when used with a windscreen having a particular curvature and the wiper blade is correspondingly curved, the surfaces of the individual yokes adjoin each other in a flush manner.

4. A windscreen wiper blade as claimed in claim 2 or 3, wherein the spoiler surfaces have a shovellike cross-section.

5. A windscreen wiper blade as claimed in any one of the preceding claims wherein each of the governing yokes has its wider portion located adjacent the narrow portion of a subordinate yoke.

6. A windscreen wiper blade as claimed in any one of the preceding claims and including a recess for attachment of a wiper arm in use of the blade, which recess is at least partly provided in part of a wider portion of a main yoke.

7. A windscreen wiper blade as claimed in any one of the preceding claims, wherein the yokes can be rotatably and lockably articulated on each other.

8. A windscreen wiper blade as claimed in claim 7, wherein a locking connection consists of an annular strip in a bore of one yoke and an annular groove on a stud of another yoke and wherein the stud has an axial bore.

9. A windscreen wiper blade substantially as herein described with reference to and as illustrated in the accompanying drawings.

10. Awindscreen wiper installation including a wiper blade as claimed in any one of the preceding claims.