Prior Art The invention relates to a wiper blade for cleaning a vehicle window according to the preamble of Claim 1 . Furthermore, the invention comprises a wiper blade/wiper arm combination using a wiper blade according to the invention. A wiper blade according to the preamble of Claim 1 is already known from practice and has a spring element which is arranged on a wiper blade adapter and has a detent button to be actuated manually as part of a detent connection, which detent button engages into a corresponding recess or opening of a wiper arm. In an operating position of the wiper blade on the wiper arm, in which operating position it is to be ensured that it is not possible to release the wiper blade from the wiper arm, the addressed detent connection is formed between the spring element and the detent opening in the wiper arm. In order to release the wiper blade from the wiper arm, for example in order to replace the wiper blade, the detent button has to be pressed into the recess or opening of the wiper arm by the operator, with the result that the detent connection is cancelled and the wiper blade can be pulled out of a receptacle of the wiper arm. Moreover, forces which act in the release direction of the detent connection occur on the detent element, for example, when passing through a car wash or on account of other circumstances. It is essential here that the said forces do not lead to the wiper blade being released from the wiper arm, whereas on the other hand relatively low forces for cancelling the detent connection are desired during a replacement of the wiper blade from the wiper arm.

Disclosure of the Invention

Proceeding from the prior art which is shown, the invention is based on the object of developing a wiper blade for cleaning a vehicle window according to the preamble of Claim 1 in such a way that firstly release of the wiper blade from the wiper arm is avoided in the case of forces which act on the detent connection and are not provided for the purpose of releasing the wiper blade from the wiper arm, whereas secondly merely relatively low forces are required to cancel the detent connection during intended dismantling of the wiper blade from the wiper arm. According to the invention, this object is achieved in a wiper blade for cleaning a vehicle window having the features of Claim 1 by virtue of the fact that the wiper blade adapter has force increasing means which are constructed to form a second swivel axis upon actuation of the detent element in a dismantling direction for releasing the detent connection, wherein a second distance is produced between the second swivel axis and the detent element which is smaller than the first distance. In other words, this means that forces of different magnitude are required for cancelling the detent connection and/or for pressing the detent element into the corresponding detent opening on the wiper arm, depending on the respective distance between the swivel axis and the detent element.

Advantageous developments of the wiper blade according to the invention for cleaning a vehicle window are indicated in the subclaims.

It is proposed in a particularly preferred structural refinement of the force increasing means that the force increasing means comprise at least one stop element, which upon actuation of the detent element in the dismantling direction comes into contact with the spring element, wherein a contact region between the stop element and the spring element forms the second swivel axis.

In order for it to be necessary to exert merely relatively low forces on the detent element in order to lift the detent connection in the case of desired dismantling of the wiper blade from the wiper arm, it is provided that the stop element is arranged so as to be swivellable elastically or is constructed elastically so that the stop element on application of a releasing force comes out of contact with the spring element by evasion or deformation.

Moreover, it is provided structurally that the wiper blade adapter has two adapter elements arranged swivellably with respect to one another, a first adapter element on which the spring element and the stop element are arranged, and a second adapter element which is connected with a wiper blade body.

In order to make it possible for an operator to release the wiper blade from the wiper arm by applying a relatively low force, it is provided that the application of a releasing force on the stop element takes place by the second adapter element when the second adapter element assumes a dismantling position in which the second adapter element has an angular position to the first adapter element which is greater than the angular positions between the two adapter elements occurring during the wiping operation. In other words, this means that the second adapter element moves or deforms the stop element into a position by way of deliberate swivelling of the two adapter elements with respect to one another, in which position the stop element is no longer in an operative connection with the spring element, with the result that the increased distance is formed between the swivel axis of the spring element and the detent element, which increased distance leads to it being possible for the detent element to be pressed into the detent opening of the wiper arm with a relatively low force. To this end, it may be provided, in particular, that the stop element on the side facing the second adapter element has a stop face which, in the dismantling position, is in contact with a chamfer constructed on the second adapter element.

In order to manufacture the addressed stop element in a manner which is as simple as possible in terms of construction and manufacturing technology, with the result that, in particular, no increased space requirement on the wiper blade adapter is required, it is provided that the stop element is formed in one piece on the wiper blade adapter and in particular is arranged within a recess on a side wall of the adapter element. It is particularly preferred if two stop elements are provided on the wiper blade adapter which are arranged symmetrically to a centre plane of the wiper blade adapter. As a result, particularly satisfactory kinematics during the introduction of the releasing forces or absorbing of particularly high forces by way of the stop elements is made possible.

Additional securing of the stop elements is achieved if on the side of the spring element facing the stop element a stop cam, associated with the stop element is arranged, which stop cam is constructed to counteract a movement or deformation of the stop element.

The invention also comprises a wiper blade/wiper arm combination which comprises a wiper blade according to the invention and a wiper arm with a detent opening into which the detent element of the wiper blade is able to be introduced with the formation of a detent connection.

Further advantages, features and details of the invention result from the following description of preferred exemplary embodiments and using the drawing, in which: Fig. 1 shows a simplified illustration of a wiping apparatus which consists of a wiper arm and a wiper blade according to the invention,

Fig. 2 shows a side view of a wiper blade adapter, as is used in a wiper blade according to the invention,

Fig. 3 shows a view in the direction of the plane III - III from Fig. 2,

Fig. 4 shows a side view of a wiper arm-side adapter element as constituent part of the wiper blade adapter from Fig. 1 ,

Fig. 5 shows a plan view of the wiper arm-side adapter element from

Fig. 4,

Fig. 6 shows a side view of the wiper blade adapter from Fig. 2, in which the two adapter elements of the wiper blade adapter are swivelled with respect to one another in order to dismantle the wiper blade from the wiper arm, and

Fig. 7 shows a section through the wiper blade adapter from Fig. 6.

Identical elements or elements with an identical function are provided with the same reference numerals in the figures.

Fig. 1 shows a wiper apparatus 100 for cleaning a vehicle window 1 , which wiper apparatus 100 comprises a wiper arm 5 which can be swivelled to and fro by a window wiper motor (not shown) and a wiper blade 10 according to the invention which is fastened exchangeably to the wiper arm 5. On an end region, on which the wiper arm 5 is connected with the wiper blade 10, on the upper side which faces away from the wiper blade 10, the wiper arm 5 has a recess in the form of an aperture 6 which is part of a releasable detent connection 15 between the wiper arm 5 and the wiper blade 10. The wiper arm 5 which substantially has a U-shaped cross section in the connection region to the wiper blade 10 is preferably composed of sheet metal and is configured as a stamped/bent part. The wiper blade 10 has a wiper blade body 16 with a wiper rubber 17 which bears against the vehicle window 1 in the operating position of the wiper blade 10.

The connection between the wiper blade 10 and the wiper arm 5 takes place by means of a wiper blade adapter 20 which can be seen, in particular, using Figs 2 and 3, is connected with the wiper blade body 16 and is a constituent part of the wiper blade 10. The wiper blade adapter 20 comprises a first adapter element 21 which can be connected with the wiper arm 5 and a second adapter element 22 which is connected with the wiper blade body 16. The two adapter elements 21 , 22 are arranged such that they can swivel with respect to one another about a rotational axis 23 which can be seen in Fig. 2, in order always to make optimum contact of the wiper rubber 17 with the vehicle window 1 possible during a movement of the wiper arm 5 along the vehicle window 1 .

A spring element in the form of a spring tongue 24 is formed in one piece on the first adapter element 21 which is composed of plastic and is configured as an injection-moulded part, on its upper side which faces away from the second adapter element 22, which spring tongue 24 has, at its free end, a detent element 25 in the form of a pushbutton, the cross section or the shape of which is adapted in a positively locking manner to the cross section or shape of the aperture 6 on the wiper arm 5, wherein the detent element 25 protrudes beyond the upper side 28 of the first adapter element 21 without the exertion of an actuating force which acts in the direction of the arrow 27 in Fig. 2. A first distance ai (Fig. 5) is formed between the connecting region 29 of the spring tongue 24 with the first adapter element 21 and the detent element 25, which distance ai identifies the distance between the detent element 25 and a first swivel axis 31 of the spring tongue 24. Together with the detent element 25, the spring tongue 24 is likewise part of the detent connection 15.

Symmetrically with respect to a centrally arranged plane of symmetry 33 (Fig. 3) of the wiper blade adapter 20, recesses 36 are formed in the two side walls 34, 35 of the adapter element 21 , within which recesses 36 in each case one stop element 38, 39 is arranged. As can be seen particularly clearly using Fig. 3, the width b of the stop elements 38, 39 increases in the direction of the upper side 28 of the first adapter element 21 , with the result that in each case one obliquely formed first stop face 41 , 42 is formed on mutually facing sides of the two stop elements 38, 39. The two stop elements 38, 39 are arranged such that they can be deformed elastically out of the position which is shown in Fig. 3 in the direction of the arrows 43, 44 in the direction of the side walls 34, 35, in such a way that they can dip as far as into the respective recess 36. Furthermore, it can be seen using Fig. 3 that in each case one detent cam 46, 47 is formed in one piece on that underside of the spring tongue 24 which faces the stop elements 38, 39, which detent cam 46, 47 limits a movement of the two stop elements 38, 39 counter to the direction of the arrows 43, 44.

Moreover, it is essential that the distance c between the two stop elements 38, 39 on the side which faces the spring tongue 24 is smaller than the width d of the spring tongue 24, with the result that, during pressing in of the detent element 25 in accordance with the direction of the arrow 27

(Fig. 2) and the illustration in Fig. 5, the spring tongue 24 comes into bearing contact by way of its underside with the two stop elements 38, 39, wherein a second swivel axis 48 is configured in such a way that a second distance a ₂ between the second swivel axis 48 and the detent element 25 is produced, which second distance a ₂ is smaller than the first distance ai

(Fig. 5). The second adapter element 22 which is connected to the first adapter element 21 such that it can be swivelled in the rotational axis 23 has a middle web 50 which protrudes between the two stop elements 38, 39. It is essential here that the middle web 50, as can be seen particularly clearly using Fig. 7, is equipped on its upper side on the side which faces the stop elements 38, 39 with in each case one chamfer 52, 53 which acts as second stop face. If the two adapter elements 21 , 22 are then swivelled by an angle a with respect to one another in accordance with the illustration in Fig. 6, wherein the angle a is greater than the angles which occur between the two adapter elements 21 , 22 during the wiping operation, the chamfers 52, 53 come into operative connection with the first stop faces 41 , 42 of the stop elements 38, 39 and move them in a manner which corresponds to the direction of the arrows 43, 44 (Fig. 3) in the direction of the side walls 34, 35, in such a way that the distance c increases such that it is greater than the width d of the spring tongue 24.

The swivelling of the two elements 21 , 22 by the angle a is carried out by an operator in order to replace the wiper blade 10 from the wiper arm 5. As a result, it is possible that the detent element 25 can be pressed into the aperture 6 of the wiper arm 5 with a relatively low actuating force, with the result that the wiper blade 10 can then be pulled together with the wiper blade adapter 20 out of the wiper arm 5 in the direction of the arrow 55 (Fig. 2). During the mounting of the wiper blade 10 on the wiper arm 5, the wiper blade adapter 20 is pushed into a substantially U-shaped receiving cross section of the wiper arm 5 (counter to the direction of the arrow 55). Here, a lower edge 56 of the first adapter element 21 with an inwardly bent-over edge of the receptacle of the wiper arm 5 and the detent element 25 with the inner side of the wiper arm 5 pass into the receiving region. When the wiper blade 10 is pushed into the wiper arm 5, the detent element 25 slides along the receptacle of the wiper arm 5, while the lower edge 56 slides along the two withdrawn side edges of the wiper arm 5. On account of the lever ratios, merely a relatively low mounting force is therefore required despite the contact of the spring tongue 24 on the two stop elements 38, 39, in order that the detent element 25 passes as far as into the region of the aperture 6, in order to form the detent connection 15. The above-described wiper blade 10 can be amended or modified in a wide variety of ways, without deviating from the concept of the invention. For instance, it is conceivable, in particular, to configure the wiper blade 10 as what is known as an "AquaBlade" wiper blade 10; this means that the wiper blade 10 has spray openings for applying a washing liquid to the vehicle window 1 . It is likewise conceivable to configure the wiper blade 10 as a heatable wiper blade.

List of reference numerals

1 Vehicle window

5 Wiper arm

6 Aperture

10 Wiper blade

15 Detent connection

16 Wiper blade body 7 Wiper rubber

20 Wiper blade adapter

21 Adapter element

22 Adapter element

23 Rotational axis

24 Spring tongue

25 Detent element

27 Arrow

28 Upper side

29 Connecting region 31 Swivel axis

33 Plane of symmetry

34 Side wall

35 Side wall

36 Recess

38 Stop element

39 Stop element

41 Stop face

42 Stop face

43 Arrow

44 Arrow

46 Detent cam

47 Detent cam

48 Swivel axis 50 Middle web

52 Chamfer

53 Chamfer

55 Arrow

56 Lower edge

100 Wiper apparatus ai First distance a ₂ Second distance b Width

c Distance d Width a Angle