Windscreen wiper device

None.

1. Field of the Invention

The present invention relates to a windscreen wiper device.

2. Related Art

The present invention relates to a windscreen wiper device comprising an elastic, elongated carrier element, as well as an elongated wiper blade of a flexible material, which can be placed in abutment with a windscreen to be wiped, which wiper blade includes opposing longitudinal grooves on its longitudinal sides, in which grooves spaced-apart longitudinal strips of the carrier element are disposed, wherein neighbouring ends of said longitudinal strips are interconnected by a respective connecting piece, which windscreen wiper device comprises a connecting device for an oscillating arm, wherein said oscillating arm is pivotally connected to said connecting device about a pivot axis near one end, with the interposition of a joint part, wherein said joint part comprises at least one resilient tongue engaging in a correspondingly shaped hole provided in said oscillating arm, and wherein said resilient tongue is rotatable along an hinge axis between an outward position retaining the wiper blade onto the oscillating arm and an inward position releasing the wiper blade from the oscillating arm.

Such a windscreen wiper device is known from European patent publication no. 1 403 156 of the same Applicant. This prior art windscreen wiper device is designed as a “yokeless” wiper device, wherein no use is made of several yokes pivotally connected to each other, but wherein the wiper blade is biased by the carrier element, as a result of which it exhibits a specific curvature. In order to connect the wiper blade onto the oscillating arm, said resilient tongue is initially pushed in against a spring force—as if it were a push button—and then allowed to spring back into the hole provided in said oscillating arm, thus snapping, that is clipping the resilient tongue into the hole. By subsequently pushing in again said resilient tongue against the spring force, the wiper blade may be released from the oscillating arm.

In practice it has become apparent that, during use of the windscreen wiper device known from the above European patent publication, high forces are exerted on the connection between the connecting device and the oscillating arm. As a consequence thereof the resilient tongue may no longer be in a proper snapped position into the hole of the oscillating arm, resulting in play between the connecting device and the oscillating arm. Eventually, the wiper blade may get loose from the oscillating arm.

The object of the invention is to provide a windscreen wiper device, wherein the connecting device and the oscillating arm are interconnected in an improved manner.

In order to accomplish that objective, a windscreen wiper device of the type referred to in the introduction is characterized according to the invention in that said resilient tongue is forced in the outward position under the influence of a moment in case a force is exerted on the wiper blade in a direction away from the oscillating arm.

Particularly, the counterforce exerted by the oscillating arm on the resilient tongue engages at a point located behind the hinge axis, seen in the direction of the force exerted on the wiper blade. In other words, said moment of force ensures in a natural way that the resilient tongue is forced automatically in its outward position, that is its position retaining the wiper blade onto the oscillating arm. On the contrary, in the above-mentioned European patent publication no. 1 403 156 of the same Applicant said moment during use compels the resilient tongue to automatically take its inward position, thereby releasing the wiper blade from the oscillating arm, with all negative consequences involved.

In one preferred embodiment of a windscreen wiper device in accordance with the invention the hinge axis is located near an outer edge of said joint part.

In another preferred embodiment of a windscreen wiper device according to the invention the oscillating arm has an at least substantially U-shaped cross-section at the location of its connection to said joint part, wherein said hole is provided in a base of said U-shaped cross-section. In addition thereto or in the alternative said joint part comprises at least two lateral resilient tongues extending outwardly, wherein the oscillating arm has an at least substantially U-shaped cross-section at the location of its connection to said joint part, and wherein each tongue engages in a correspondingly shaped hole provided in a leg of said U-shaped cross-section.

In another preferred embodiment of a windscreen wiper device in accordance with the invention said hole(s) has/have a closed circumference. Such (a) closed hole(s) enhance(s) the retention of the connection device/joint part onto the oscillating arm in all possible directions, particularly both horizontally and vertically. In the alternative, said hole(s) has/have a non-closed circumference.

In another preferred embodiment of a windscreen wiper device according to the invention said joint part is made of plastic (including any synthetic material having some flexibility).

In another preferred embodiment of a windscreen wiper device in accordance with the invention said joint part is attached to said connecting device by pivotally engaging protrusions of said connecting device, at the location of said pivot axis, in recesses provided in said joint part. These protrusions that function as bearing surfaces are spaced far apart, so that the forces exerted thereon will be relatively low.

In another preferred embodiment of a windscreen wiper device according to the invention said joint part has an at least substantially U-shaped cross-section at the location of its attachment to said connecting device, and wherein said joint part in each leg of said U-shaped cross-section is provided with a recess provided coaxially with said pivot axis. Preferably, the protrusions extend outwards on either side of said connecting device, wherein the protrusions are cylindrical. Particularly, the recesses are correspondingly shaped.

The invention will now be explained in more detail with reference to figures illustrated in a drawing, wherein:

FIG. 1 is a perspective, schematic view of a preferred embodiment of a windscreen wiper device in accordance with the invention;

FIG. 2 is a perspective, schematic view of a connecting device as used in FIG. 1 , as well as a joint part and (an end of) a oscillating arm according to another preferred embodiment in accordance with the invention;

FIG. 3 shows various successive steps for fitting the connecting device, the joint part and the oscillating arm of FIG. 2 together; and

FIGS. 4 and 5 relate to several views of a joint part of FIGS. 2 and 3 ;

FIGS. 6 , 7 and 8 refer to a prior art windscreen wiper device, wherein it is shown how the connecting device may get loose from the oscillating arm;

FIGS. 9 , 10 and 11 concern a windscreen wiper device according to the invention showing the improved connection between the connecting device and the oscillating arm; and

FIGS. 12 and 13 concern a windscreen wiper device according to an alternative embodiment of the invention.

FIG. 1 shows a preferred variant of a windscreen wiper device 1 according to the invention. Said windscreen wiper device 1 is built up of an elastomeric wiper blade 2 , in the longitudinal sides of which opposing longitudinal grooves 3 are formed, and of longitudinal strips 4 made of spring band steel, which are fitted in said longitudinal grooves 3 . Said strips 4 form a flexible carrier element for the wiper blade 2 , as it were, which is thus biased in a curved position (the curvature in operative position being that of a windscreen to be wiped). Neighbouring ends 5 of the strips 4 are interconnected on either side of the windscreen wiper device 1 by means of connecting pieces 6 functioning as clamping members. In this embodiment, the connecting pieces 6 are separate constructional elements, which may be form-locked (“positive locking” or “having a positive fit”) or force-locked to the ends 5 of the strips 4 . In another preferred embodiment, said connecting pieces 6 are in one piece with the strips 4 made of spring band steel. In the latter case said connecting pieces 6 form transverse bridges for the strips 4 , as it were.

The windscreen wiper device 1 is furthermore built up of a connecting device 7 of plastic material for an oscillating arm 8 . Alternatively, the connecting device 7 may also be made of metal, such as steel or aluminum. The connecting device 7 comprises clamping members 9 that are integral therewith, which engage round longitudinal sides of the strips 4 that face away from each other, as a result of which the connecting device 7 is firmly attached to the unit consisting of the wiper blade 2 and the strips 4 . The oscillating arm 8 is pivotally connected to the connecting device 7 about a pivot axis near one end, as will be described hereunder.

With reference to FIG. 2 the connecting device 7 comprises two cylindrical protrusions 10 extending outwards on either side of said connecting device 7 . These protrusions 10 pivotally engage in identically shaped cylindrical recesses 11 of a plastic joint part 12 . In the alternative the recesses 11 may have a non-closed shape (i.e. open circumference). Said protrusions 10 act as bearing surfaces at the location of a pivot axis in order to pivot the joint part 12 (and the oscillating arm 8 attached thereto) about said pivot axis near one end of the oscillating arm 8 . The protrusions 10 are preferably in one piece with the connecting device 7 ; in the alternative, the protrusions 10 are part of a single pivot pin perpendicular to the connecting device 7 . Said connecting device 7 may be equipped with a cover or cap in order to obtain an aesthetic appearance thereof, to avoid sharp edges and to provide protection against UV-light etcetera. The joint part 12 comprises one resilient tongue 13 extending outwardly, while the oscillating arm 8 has an U-shaped cross-section at the location of its connection to said joint part 12 , so that the tongue 13 engages in an identically shaped hole 14 provided in a base 15 of said U-shaped cross-section.

FIG. 3 shows the steps of mounting the connecting device 7 with the wiper blade 2 (not shown) onto the oscillating arm 8 . The joint part 12 being already clipped onto the connecting device 7 is pivoted relative to the connecting device 7 , so that said joint part 12 can be easily slid on a free end of the oscillating arm 8 . During this sliding movement the resilient tongue 13 is initially pushed in against a spring force and then allowed to spring back into said hole 14 , thus snapping, that is clipping the resilient tongue 13 into the hole 14 . This is a so-called bayonet-connection. The oscillating arm 8 together with the joint part 12 may then be pivoted back in a position parallel to the wiper blade 2 in order to be ready for use. By subsequently pushing in again said resilient tongue 13 against the spring force (as if it were a push button), the connecting device 7 and the joint part 2 together with the wiper blade 2 (not shown) may be released from the oscillating arm 8 . Dismounting the connecting device 7 with the wiper blade 2 (not shown) from the oscillating arm 8 is thus realized by sliding the connecting device 7 and the joint part 2 together with the wiper blade 2 (not shown) in a direction away from the oscillating arm 8 .

Each leg 16 of the U-shaped cross-section of the oscillating arm 8 comprises clamping members formed as inwardly bended edges 17 integral with said legs 16 , wherein during use said edges 17 engage round longitudinal sides of said joint part 12 that face away from each other. Thus an enhanced retention of the connecting device 7 /joint part 12 onto the oscillating arm 8 is achieved in vertical direction, that is perpendicular to the longitudinal direction of the oscillating arm 8 .

FIGS. 4 and 5 relate to several views of a joint part of FIGS. 2 and 3 . Said resilient tongue 13 is rotatable along an hinge axis 18 (located near an outer edge of said joint part 12 ) between an outward position retaining the wiper blade 2 onto the oscillating arm 8 and an inward position releasing the wiper blade 2 from the oscillating arm 8 . According to an essential feature of the invention said resilient tongue 13 is forced in the outward position under the influence of a moment in case a force is exerted on the wiper blade 2 in a direction away from the oscillating arm 8 . Particularly, the counterforce exerted by the oscillating arm 8 on the resilient tongue 13 engages at a point located behind the hinge axis 18 , seen in the direction of the force exerted on the wiper blade 2 . In other words, said moment of force ensures in a natural way that the resilient tongue 13 is forced automatically in its outward position, that is its position retaining the connecting device 7 , the joint part 12 and the wiper blade 2 (not shown) onto the oscillating arm 8 .

In FIGS. 6 , 7 and 8 a windscreen wiper device according to the prior art, for example of the type is described in European patent publication no. 1 403 156 indicated earlier, is shown, wherein corresponding parts have been designated by the same reference numbers. In case a force is exerted on the wiper blade 2 in a direction of the arrow of FIG. 7 , the counter force exerted by the oscillating arm 8 may cause the resilient tongue 13 to be pushed inwardly, so that the wiper blade 2 may get loose from the oscillating arm 8 (see FIG. 8 ).

As can be seen in FIGS. 9 , 10 and 11 corresponding to FIGS. 6 , 7 and 8 , respectively, the counterforce exerted by the oscillating arm 8 as mentioned above automatically forces the resilient tongue 13 in the outward position, thereby retaining the wiperblade 2 on the oscillating arm 8 ( FIG. 11 ).

FIGS. 12 and 13 depict an alternative embodiment of the invention, wherein the joint part 12 comprises at least two lateral resilient tongues 13 extending outwardly. Each tongue 13 engages in a correspondingly shaped hole 14 provided in each leg 16 of its U-shaped cross-section.

Possibly, a spoiler 19 is furthermore provided ( FIG. 1 ).

The invention is not restricted to the variants shown in the drawing, but it also extends to other embodiments that fall within the scope of the appended claims.