WO2012089600A1

WO2012089600A1 - Wiper arm connection and windscreen wiper drive with a wiper arm connection

Info

Publication number: WO2012089600A1
Application number: PCT/EP2011/073699
Authority: WO
Inventors: Wolfgang Scholl; Martin Grupp
Original assignee: Valeo Wischersysteme GmbH
Current assignee: Valeo Wischersysteme GmbH
Priority date: 2010-12-29
Filing date: 2011-12-21
Publication date: 2012-07-05
Anticipated expiration: 2013-06-29
Also published as: DE102010056362A1

Abstract

The invention relates to a wiper arm connection (10), with a wiper arm element (11) which is able to be connected so as to be locked against relative rotation on an axis (12) of a windscreen wiper drive for a motor vehicle, wherein the axis (12) has a conical first contact section (21) arranged in operative connection with the wiper arm element (11), wherein the first contact section (21) has a first toothing (23) in particular in the form of a knurl, which cooperates with a second contact section (22), which is likewise conical, constructed on the wiper arm element (11) in the region of a mounting (17). According to the invention, provision is made that the second contact section (22) in the wiper arm element (11) has a second toothing (28), in particular in the form of a knurl, and that the two toothings (23, 28) come into operative connection upon axial joining together of the two contact sections (21, 22).

Description

WIPER ARM CONNECTION AND WINDSCREEN WIPER DRIVE WITH A

WIPER ARM CONNECTION

Prior art

The invention relates to a wiper arm connection according to the introductory clause of Claim 1. The invention further relates to a windscreen wiper drive with a wiper arm connection according to the invention.

A wiper arm connection according to the introductory clause of Claim 1 for connecting a wiper arm element with the axis of the windscreen wiper drive is already generally known from practice. Here, the cooperating regions of the wiper arm element and of the axis of the wiper drive respectively have a cone-shaped contact region, which come into operative connection on axial bracing of the wiper arm element by means of a nut on the axis of the windscreen wiper drive. Furthermore, the axis of the windscreen wiper drive has a toothing in the form of a knurl with longitudinal grooves, the teeth of which run in longitudinal direction of the axis of the windscreen wiper drive. Thereby, on axial bracing of the wiper arm element, the teeth bury themselves into the mounting of the wiper arm element, so that in addition to the force-fitting connection via the nut, an additional form fit is formed between the axis and the wiper arm element through a plastic deformation of the material of the wiper arm element. However, it is a prerequisite here that the wiper arm element consists of a softer material than the toothing of the axis .

On the installation of the wiper arm element during the production of the motor vehicle at the car manufacturer's, the wiper arm element must be provided and fastened in a defined installation position onto the axis of the windscreen wiper drive. This takes place in practice by tightening the nut on the axis of the windscreen wiper drive. Thereby, depending on how the tightening torque is applied, the wiper arm element can turn to the axis of the windscreen wiper drive, or the axis of the windscreen wiper drive can turn to the wiper arm element. In particular, thereby a subsequent unintentional displacement of the angular position of the wiper arm element to the axis of the windscreen wiper drive can occur. This applies especially to the new, direct-driven wiper motors, in which the wiper arm element is screwed directly onto the wiper motor output axis. So that the axes of these directly driven motors do not distort, the motors must be supplied with current in order to prevent an unintentional displacement of the angular position of the wiper arm element to the axis.

Disclosure of the invention Proceeding from the represented prior art, the invention is based on the problem of further developing a wiper arm connection according to the introductory clause of Claim 1, such that the mounting process of the wiper arm element during the production of the motor vehicle is simplified, in particular that unintentional angle alterations between the wiper arm element to the axis of the windscreen wiper drive can not occur. At the same time, in particular in the direct-driven wiper motors, the current consumption of the wiper motor is to be reduced, because the latter must only generate a small torque. This problem is solved in a wiper arm connection with the features of Claim 1. The invention is based here on the idea of equipping the wiper arm element with an additional second toothing, which cooperates with the first toothing constructed on the axis of the windscreen wiper drive. Thereby, the two toothings already come into operative connection on the light placing onto each other or respectively axial joining together, so that even without the fastening or respectively bracing of the wiper arm element on the axis by means of the nut, a fixing is formed between the axis and the wiper arm element .

Advantageous further developments of the wiper arm connection according to the invention are indicated in the sub-claims. All combinations of at least two of the features disclosed in the claims, in the description and/or in the figures fall within the scope of the invention.

In a first structural realization of the invention, provision is made that the number of teeth of the two toothings is of equal amount. Thereby, on the axial joining together of the wiper arm connection a particularly good form fit is achieved between the two toothings.

Alternatively, however, provision may also be made that the number of teeth of the two toothings is of different amounts, wherein the number of teeth of the second toothing is less than the number of teeth of the first toothing. With such an embodiment of the invention, in particular the manufacturing process of the second toothing, constructed on the wiper arm element, can be simplified, because the toothing geometry is simplified.

In particular the toothing can be furthermore constructed in a particularly simple manner on a wiper arm element if the latter is constructed as a cast part, in particular as an aluminium pressure die casting, at least in the region of the second contact section.

To achieve the final secure connection of the wiper arm connection, provision is preferably made that the wiper arm element is braced axially on the axis by means of a fastening element constructed as a nut.

The invention also comprises a windscreen wiper drive with a wiper arm connection according to the invention. Such a windscreen wiper drive can be installed or respectively positioned in a particularly simple manner during the manufacture of the motor vehicle. Further advantages, features and details of the invention will emerge from the following description of preferred example embodiments and with the aid of the drawings, showing in: Fig. 1 a longitudinal section through a wiper arm

connection according to the invention, using two toothings on the axis of the windscreen wiper drive and the wiper arm element and Fig. 2 a bottom view of a wiper arm element in

perspective view.

In Fig. 1 a wiper arm connection 10 is illustrated, as is used for fastening a windscreen wiper, not illustrated in further detail, which serves for cleaning a window of a motor vehicle. The wiper arm connection 10 comprises a wiper arm 11, one end of which is connected with an axis 12 of a windscreen wiper drive which is not illustrated in further detail. Here, the axis 12 can be for example the drive axis of a windscreen wiper motor, in particular constructed so as to be reversible, which means that the wiper arm 11 is driven directly by the windscreen wiper drive, or else the axis 12 is coupled with a windscreen wiper motor via a wiper linkage, likewise not illustrated. In both cases, by means of the axis 12 the wiper arm 11 and the longitudinal axis 13 of the axis 12 is pivoted to and fro .

On the side lying opposite the axis 12, the wiper arm 11 has a bearing eye 14, in which by means of a bearing pin, which is not illustrated, a wiper rod, which is likewise not illustrated, is pivotably mounted, which at its end carries in turn the actual windscreen wiper. The wiper arm 11 is preferably constructed as a pressure die casting, particularly as an aluminium pressure die casting. Alternatively, it can also be constructed as a zinc pressure die casting or as a steel stamped part. In addition, on the region which is to be connected with the axis 12, the wiper arm 11 has a round or respectively cylindrical outer wall 15 with an intermediate base 16. In the intermediate base 16 a through-bore 17 is constructed, which has a conical shape, wherein the diameter of the through-bore 17 is greater on the side facing the axis 12 than on the side facing away from the axis 12.

Beneath the wiper arm 11, the axis 12 is surrounded by an elastic protective sleeve 18 in the form of a sealing element, in order to prevent the access of moisture or respectively water in the direction of the drive of the axis 12. In addition, the axis 12 is surrounded substantially beneath the wiper arm 11 by a covering 19, which is at least partially embraced on its circumference by the outer wall 15 of the wiper arm 11. The axis 12 has a first contact section 21, which in accordance with the conicity of the through-bore 17, which in turn forms a second contact region 22, is likewise constructed in a conical shape. In addition, the first contact section 21 has a first toothing 23, wherein the teeth 24 of the first toothing 23 are aligned in longitudinal direction of the axis 12. The axis 12, which is constructed in particular from steel, has in addition at its end facing the wiper arm 11 an external thread 25, onto which, with the mounted wiper arm 11, a fastening element in the form of a nut 26 is able to be screwed. The nut 26 serves for the axial bracing of the wiper arm 11 on the axis 12.

According to the invention provision is made that the through-bore 17 of the wiper arm 11 has a second toothing 28 in the second contact section 22. The second toothing 28, like the first toothing 23, is preferably constructed as a knurl with teeth 29.

The number of teeth 24 and 29 of the two toothings 23 and 28 can be of equal amount, so that on the axial joining together or respectively on placing of the wiper arm 11 onto the axis 12, each of the teeth 24, 29 comes into operative connection with another tooth 29, 24. However, in particular for reasons of simpler producibility of the wiper arm 11, provision can also be made that the number of teeth 29 of the second toothing 28 is less than the number of teeth 24 of the first toothing 23.

On the pre-mounting of the wiper arm 11 onto the axis 12, it suffices to merely apply a relatively light placement force on the wiper arm 11 in the direction of the axis 12, wherein the two toothings 23, 28 come into operative connection with each other. An axial secure bracing of the wiper arm 11 by means of the nut 26 is likewise no longer necessary in the pre-mounting. Only as soon as the final position of the wiper arm 11 to the axis 12 is certain is the wiper 11 fastened by means of the nut 26 in its final axial position on the axis 12. If, in so doing, the height of the teeth 24 is greater than the corresponding height of the teeth 29, the teeth 24 bury themselves during axial bracing into the grooves situated between the teeth 29, so that in addition to the actual form fit via the teeth 24, 29 of the two toothings 23, 28, an additional plastic deformation of the wiper arm 11 takes place in the region of the second toothing 28.

The wiper arm connection 10 which has been described so far can be altered or respectively modified in a variety of ways, without departing from the idea of the invention. The latter consists in the provision of a second toothing 28 on the wiper arm 11, in order to achieve a form fit between the two parts on a pre-mounting of the wiper arm 11 on the axis 12, which form fit holds the wiper arm 11 securely in a pre-mounting position.

List of reference numbers

10 wiper arm connection

11 wiper arm

12 axis

13 longitudinal axis

14 bearing eye

15 outer wall

16 intermediate base

17 through-bore

18 protective sleeve

19 covering

21 contact section

22 contact section

23 toothing

24 tooth

25 external thread

26 nut

28 toothing

29 tooth

Claims

1. Wiper arm connection (10), with a wiper arm element (11) which is able to be connected so as to be locked against relative rotation on an axis (12) of a windscreen wiper drive for a motor vehicle, wherein the axis (12) has a conical first contact section (21) arranged in operative connection with the wiper arm element (11), wherein the first contact section (21) has a first toothing (23) in particular in the form of a knurl, which cooperates with a second contact section (22), which is likewise conical, constructed on the wiper arm element (11) in the region of a mounting (17), characterized in that the second contact section (22) in the wiper arm element (11) has a second toothing (28), in particular in the form of a knurl, and that the two toothings (23, 28) come into operative connection upon axial joining together of the two contact sections (21, 22) .

2. Wiper arm connection according to Claim 1,

characterized in that

the number of teeth (24, 29) of the two toothings (23, 28) is of equal amount.

3. Wiper arm connection according to Claim 1,

characterized in that

the number of teeth (24, 29) of the two toothings (23, 28) is of different amounts, and that the number of teeth (29) of the second toothing (28) is less than the number of teeth (24) of the first toothing (23) .

4. Wiper arm connection according to one of Claims 1 to 3,

characterized in that

the wiper arm element (11) is constructed as a cast part, in particular as an aluminium pressure die casting, at least in the region of the second contact section ( 22 ) .

5. Wiper arm connection according to one of Claims 1 to 4,

characterized in that

the wiper arm element (11) is braced axially on the axis (12) by means of a fastening element constructed as a nut ( 26 ) .

6. Windscreen wiper drive with a wiper arm connection (10) according to one of Claims 1 to 5.