GB2428560A

GB2428560A - Wiper blade for panes of a motor vehicle

Info

Publication number: GB2428560A
Application number: GB0614846A
Authority: GB
Inventors: Peter De Block; Eric Windmolders; Hans Beelen
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2005-08-03
Filing date: 2006-07-26
Publication date: 2007-02-07
Anticipated expiration: 2026-07-26
Also published as: DE102005036443A1; FR2889499A1; GB0614846D0; FR2889499B1; GB2428560B

Abstract

A wiper, particularly for a pane (24) of a motor vehicle, for damping oscillations which can cause a wiper blade to judder over the pane, comprises a wiper arm (12), a wiper blade (16), which comprises at least one wiper strip (20) placeable against the pane, and an additional guide arranged at, in particular, an end (26) of the wiper blade (16). The guide has damping means (30) to damp movement between the wiper blade (16) and the wiper arm (12). The damping device (30) damps relative movement between a first part (32, fig 2) and a second part (34, fig 2), and may comprise a resilient region (40, fig 2). The second part may be of oval form and include a guide track (44, fig 2) providing a guide region (42, fig 2).

Description

1 2428560

WIPER

The present invention relates to a wiper.

A device for guiding a wiper blade, particularly a blade for panes of motor vehicles, is known from DE-A-102 10 720, wherein a dip is provided with a guide pin which is fastened on a wiper strip carrier and/or a wiper strip and which extends in the longitudinal direction of the wiper blade and has lateral guide surfaces. The device is to prevent oscillation of the wiper blade relative to the wiper arm during the wiping process. However, it has proved that this guide does not work in optimum manner particularly in the case of long wiper blades.

According to the present invention there is provided a device for guiding a wiper blade particularly for panes of motor vehicles, which comprises at least one wiper strip placeable against the pane and a connecting device for a wiper arm and an additional guide arranged at, especially, an end of the wiper blade, charactensed in that the guide has damping means which damps a movement between the wiper blade and the wiper arm.

Such a device has the advantage that possible relative movements between the wiper arm and the wiper blade are damped. The invention recognises that a purely rigid guide or also a purely resilient guide can indeed influence, but not prevent, oscillatory behaviour.

Depending on the respective resonance behaviour, rigid or purely resilient guides can be completely ineffective or even have an amplifying effect. Only if a damping component is introduced can the tendency to oscillation be reduced, if not completely eliminated. Where the damping means is arranged is oriented towards the resonance behaviour of the installed system and embraces the regions of the wiper blade ends, the regions between the wiper blade ends and the connecting device, and the connecting device itself. As a rule, however, the preferred location is in the region of the wiper blade end arranged at the inner cirde of the wiping arc.

The damping means can be arranged to damp only a movement parallel to the wiper arm, thus perpendicular to the pane, or only a movement along the wiper arm, thus parallel to the pane, or movements in both directions. The preferred variant depends on the resonance behaviour of the system.

The device can be more easily adapted to the system of wiper blade and wiper arm if at least one resilient region is provided by way of which relative movements can be absorbed. In addition, this resilient region has no damping characteristics depending on the respective material selection.

A preferred damping direction can be set through construction of a guide region within the damping means. This takes place in particularly simple manner if the guide region has a guide track and a guide body guided in the guide track. The damping can be set by friction between the guide body and the guide track.

A pin arranged at, for example, an end cap of the wiper blade can serve as a simple guide body. This can then move in a guide track preferably oriented towards the wiper arm. In this manner the guide region has a longitudinal orientation facing towards the wiper arm.

A very simple construction results if the damping means comprises merely two parts, wherein a first part is arranged at the wiper blade and a second part at the wiper arm. The first part can be, for example, the already mentioned pin, whilst the second part preferably comprises an annular, oval region with which a resilient region is connected. The annular region then contains the guide track within which the pin can move. Relative movements can be absorbed by way of the resilient region.

In order to optimise the friction forces within the damping means it is of advantage for at least the second part to be made of a plastics material. Elastomers having the surfaces which increase direct coefficients are also suitable for this purpose. Any coefficients of friction can be predetermined by a suitable pairing of the materials of the first and the second parts.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings. in which: Fig. 1 is a side view of a wiper and Fig. 2 is a detail perspective view of the wiper of Fig. 1 in the region II.

Referring now to the drawings there is shown in Fig. I part of a wiper 10 with a wiper arm 12 connected with a wiper blade 16 by way of a connecting device 14. The wiper blade 16 substantialiy consists of a camer element 18, a wiper strip 20 and a spoiler 22 and in Fig. I is shown resting on a pane 24 of a motor vehicle. The spoiler 22 and the carrier element 18 are covered by end caps 28 at the wiper blade ends 26.

Arranged in the region of one end cap 26 is a damping device 30 which damps the relative movement between the wiper blade 16 and the wiper arm 12. In the illustrated embodiment the damping device 30 is arranged at the wiper blade end 26, facing towards the axis of pendulation (not illustrated) of the wiper arm 12 and thus lies at the inner circle of the arcuate wiping movement of the blade. The damping device 30 could also be located in the region between the wiper blade end 26 and the connecting device 14 or in the region of the connecting device 14. In the case of embodiments in which the wiper arm is extended, for example for design reasons, up to the front wiper blade end 26 the damping device 30 can also be arranged in this region.

It can be seen in Figure 2 that the damping device 30 consists of a first part 32 and a second part 34. The damping device 30 damps a relative movement between the first part 32 and the second part 34, which are arranged at the wiper blade 16 and the wiper arm 12, respectively. The damping takes place both in a direction 36 parallel to the wiper arm 12 and in a direction 38 perpendicular to the wiper arm 12.

The damping device 30 has for this purpose a resilient region 40 enabling relative movements as such. The resilient region 40 can preferably also have damping characteristics.

Moreover, the damping device 30 comprises a guide region 42 comprising a guide track 44. Corresponding with this guide track 44 is a pin 46 which during the relative movement is moved frictionally along the guide track 44. A damping moment is produced by this friction.

The second part 34 is of annular, oval form, the guide track 44 being formed within the ring 48. The resilient region 40, which in turn has a fastening plate 50 by way of which the second part 34 is fastened to the wiper arm 12, is connected with the annular region.

The second part 34 is made of plastics material. A thermoplastic plastics material or an elastomer is particularly suitable. It is also conceivable to cover only the guide region 42 or the guide track 44 with an elastomer. Significant for the selection of the material is the desired friction, or the coefficient of friction to be set, between the pin 46 and the guide track 44. The friction is additionally influenced by the force present between the guide track 44 and the pin 46. This force can be set by the geometric relationships, particularly by the diameter of the pin 46 and the clear width of the guide track 44. A press fit producing a constant force of the guide track 44 on the pin 46 can be provided here. This force is then increased in the edge regions of the annular, oval ring 48 so that the damping effect is greater in those regions.

During the wiping operation, the wiper arm 12 and the wiper blade 16, or at least the wiper blade end 26 thereof, move parallel to one another as a consequence of the system, since the windscreen 24 has different curvatures which the wiper blade or the wiper blade ends 26 must follow. This movement is made possible by the resilient region 40. Oscillations of the wiper blade 16, which can cause the blade to judder over the screen 24, are largely precluded by the damping in the direction 38 perpendicular to the wiper arm 12. The pin 46 can move within the guide region 42, but is constantly braked by the prevailing friction.

It is also conceivable to provide a construction, similar to the guide region 42, for the direction 36 parallel to the wiper arm 12.

Claims

1. A wiper comprising an arm, a blade connected with the arm by connecting means and having a wiper strip for wiping a pane, and a guide comprising damping means for damping relative movement of the blade and arm.

2. A wiper as claimed in claim 1, wherein the guide is arranged at an end of the arm.

3. A wiper as claimed in claim I or claim 2, the damping means being arranged to damp the relative movement in a direction parallel to the arm.

4. A wiper as claimed in any one of the preceding claims, the damping means being arranged to damp the relative movement in direction towards the arm.

5. A wiper as claimed in any one of the preceding claims, the damping means having a resilient region.

6. A wiper as claimed in any one of the preceding claims, the damping means having a guide region.

7. A wiper as claimed in claim 6, wherein the guide region comprises a guide track and a guide body guided in the track.

8. A wiper as claimed in claim 7, wherein the guide body comprises a pin arranged at the blade.

9. A wiper as claimed in any one of claims 6 to 8, wherein the guide region has a longitudinal orientation facing the arm.

10. A wiper as claimed in any one of the preceding claims, the damping means comprising a first part arranged at the blade and a second part separate from the first part and arranged at the arm.

I 1. A wiper as claimed in claim 10, wherein the second part includes an oval annular region connected with the resilient region.

12. A wiper as claimed in claim 10 or claim 11, wherein the second part is made of plastics material.

13. A wiper blade for a wiper as claimed in any one of the preceding claims, the blade carrying part of the damping means.

14. A wiper arm for a wiper as claimed in any one of the preceding claims, the arm carrying part of the damping means.