DE3448060A1 - Wiper arm in window washing systems of motor vehicles - Google Patents

Abstract

The invention is concerned with a wiper arm for window washing systems of motor vehicles, having a bearing part which is located between a wiper arm and wiper shaft, coupling of the wiper arm to the bearing part via a swivel axis, swivellability of the wiper arm out of a contact position against the window into a position of rest in which it is raised off the window and at an acute angle with respect to the contact position, and with stressing of the wiper arm in the contact direction against the window by means of a tension spring element. In order to permit a positionally more stable position of rest of the raised wiper arm, there is provision for the wiper arm to be coupled in its position of rest with respect to the bearing part via a support element which engages on the bearing part and on the wiper arm, one of whose couplings is constructed as a sliding guide which in the position of rest of the wiper arm forms a catch connection so that, in its position of rest, the wiper arm is additionally supported on the bearing part in a positive fashion by means of the support element.

Description

q / / ο η cn Daimler-Benz Aktiengesellschaft Daim 15 390A / 4

Stuttgart-Untertürkheim EPT br-schm

December 16, 1985

"Wiper arm in windshield wiper systems in motor vehicles"

The invention relates to a wiper arm in windshield wiper systems of motor vehicles of the type specified in the preamble of claim 1.

W Such a wiper arm is known from DE-PS 2,105,101. The tension spring element causing the load on the wiper arm runs there in the contact position sideways \ borrowed in the direction of the window and past the pivot axis, namely in the direction of the free end of the wiper arm, with an increase in the distance to the window obliquely to the longitudinal extension of the Wiper arm running line of action. The fixation in the rest position is done by shifting the line of action

of the tension spring element away from the disc into a position in which the line of action of the Federeleraentes - based on the starting position in the contact position the other side of the pivot axis, and thus offset above the dead center, runs. The conversion

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is thereby made possible that the connection of the tension spring element to the pivot point on the bearing part side by means of a The hook is bent towards the window and causes the tension spring element to pivot past when the wiper arm is lifted into the rest position on the pivot axis between the wiper arm and the bearing part.

Such a lifted one, in its rest position by over-center pull The wiper arm held by the tension spring element is fixed, but even at angles of lift of approx. 45 degrees not fixed in a very stable position.

If the lift-off angle is to be significantly smaller for structural reasons, it is basically possible to use the known To modify the wiper arm in such a way that the articulation point of the tension spring element on the bearing part continues to the outside, ie to a larger distance based on the plane of the pane. On the other hand, this increases the distance the line of action of the tension spring element to the pivot axis between the wiper arm and the bearing part is lower in the contact position,

Since a sufficient contact force of the wiper arm must nevertheless remain guaranteed, this inevitably led to a oversized tension spring element with an extremely hard spring rate, which inevitably leads to a significant increase in the Operating forces when lifting the wiper arm would result.

Thus, such a construction can also be used for solutions with small lifting angles between the contact and rest position seldom use the wiper arm.

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Furthermore, a wiper arm is already known from FR-PS 1.206.581, on the bearing part of which a support member is articulated, which runs in an operating position in the direction of the wiper arm and the wiper arm in a raised rest position supported against the bearing part, wherein it is employed at an angle to the wiper arm.

The contact force of the wiper arm is generated here by means of a compression spring, the spring tension of which in the support direction of the support member is effective. Therefore, a fixed, lifted rest position of the wiper arm is an over-center position of the support member based on the bearing axis of the wiper arm on the bearing part required, so that there is also a Such a construction can hardly be used for solutions with small pivot angles between the operating and rest position.

It also requires the use of the compression spring principle for spring loading of the wiper arm a significantly higher construction cost, since a helical compression spring to raise a defined compression or rebound movement requires additional axial guidance and not simply on the bearing part or can be supported on the wiper arm.

/ L The invention is based on the object of a generic To further develop the wiper arm so that it is suitable for solutions with small lift-off angles between the contact and rest position is suitable, and that it is reliably fixed in the rest position.

The inventive solution to this problem is the subject the characterizing features of claim 1.

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Advantageous refinements of the invention are shown in FIG characterizing features of claims 2 to 8.

The following are four embodiments of one according to the invention Wiper arm explained using a graphic representation, namely show

Figure 1, Figure 3, each a longitudinal section through one

Figure 5 and the joint-side lower section of a

FIG. 7 a wiper arm and 15

Figure 2, Figure 4, associated rear views of the entFigur 6 and speaking sections. Figure 8

In Figure 1 and 2, a wiper arm 1 is connected via a pivot bearing 2 to a bearing part 3, which is to be driven Wiper shaft is attachable. The bearing part 3 is extended beyond the pivot bearing 2 to an extension 10, in which a bore 11 is located. A rectangular bent spring clip 12 made of spring wire is on his open side with the angled legs in this hole

11 inserted so that the spring clip 12 is pivotably mounted. With the opposite short bracket section lies the spring clip 12 in the lifted position of the wiper arm 1 in a clip opening 13 of a clip-shaped plastic clip 14 at. The spring clip 12 thus acts as a support for the wiper arm 1. Two sides of the spring clip 12 run Handle coil springs 15 which are hinged above the support point on the wiper arm 1 and on the bearing part 3, their Line of action between the wiper arm 1 and the spring clip

12 runs.

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The plastic clip 14 is fastened on the wiper array side in that a wiper rod 16 bent in a lower section is angled at its free end by approximately 90 degrees is and in a receiving opening 17 of the plastic clip 14 is plugged in. -

So that in the lifted position of the wiper arm 1 a sufficient locking of the same is ensured, the clamping forces of the plastic clip 14 are to be dimensioned so that the diagonal pull of the handle eyelet coil springs 15 does not lead to the spring clip 12 sliding out of the plastic clip can lead. The force for moving the wiper arm 1 into the operating position indicated by broken lines must be applied in the usual way by manual action. ,

When the wiper arm 1 is lifted off, the locked position is lifted, due to the offset articulation points Wiper arm 1 and spring clip 12, automatically resumed.

Figure 3 and Figure 4 show a variant of the wiper arm 1, in which a link control is used to lock the lifted position. The backdrop used for this 18 is formed in one piece and here consists of a brass alloy. It is on the lower one as shown Section of the wiper rod 16 supported and this serves due to its resilient design as a detent spring, the cooperates with the backdrop 18. The deflectable leg of the spring clip 12 slides when lifting or pressing the Wiper arm 1 over the trajectory of the backdrop 18, where he

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Due to the elastic pretensioning of the wiper rod 16, it is always in contact with the link 18. In the lifted position of the wiper arm 1 is the leg of the spring clip 12 between a blocking cam 18a and the angled free end the wiper rod 16, which thus also serves as a stop to limit the extension of the spring clip 12. The approach slope of the blocking cam 18a is to be matched to the bias of the lower portion of the wiper rod 16 that the desired locking force of the wiper arm 1 is achieved in the lifted position.

Figure 5 and Figure 6 show a variant of a wiper arm 1, in which the support member of a strut 19 of U-shaped cross-section is formed. The strut 19 is on a bearing axis 20, which lies in the bore 11 of the extension 10, pivotally mounted and has at the opposite end a hook-shaped end part 19a, in which a guide pin ' zen 21 is guided under axial displacement protection. The guide pin 21 is by a in the direction of the upper Wall of the wiper arm 1 spring-loaded link 22 is applied. The spring load is here by a free Applied to the end of a wiper rod 23 which simultaneously holds the link 22 by means of a bracket 25. At the console 25 are the handle eyelet coil springs on both sides of the backdrop 22 15 hooked. To lock the wiper arm 1, the guide pin 21 engages in a recess 24 of the Backdrop 22 a.

Another possibility for locking the wiper arm 1 can be seen from FIG. 7 and FIG. Here is the Support member formed by a twisted flat strut 26.

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The end on the wiper arm side is angled by about 90 degrees and suspended in a bracket 27, the suspension points for the handle eyelet coil springs 15 next to this end are hooked into the console 27. The console 27 is in turn fastened to the wiper rod 23. So that at the

10 'hanging point of the flat strut 26 no rattling noises arise can, an elastic buffer element 28 is attached here. That is the point where the twisted flat strut is hung 26 opposite end is by means of a bolt 29 in a slot guide 30 of a U-shaped forked extension 31 mounted longitudinally displaceable. The bolt 29 is made of spring wire via a U-shaped bent detent spring 32, which is on the bearing part side is supported, spring-loaded, the slightly angled ends of the detent spring 32 resting on the bolt 29. By choosing a suitable spring identifier for the detent spring 32, the wiper arm 1 is thus in the raised position reliably lockable.

Claims (8)

Claims 1. Wiper arm for windshield wiper systems in motor vehicles with a bearing part lying between the wiper arm and the wiper shaft, articulation of the wiper arm on the bearing part a pivot axis, pivotability of the wiper arm from a contact position against the window in one of of the windshield raised rest position at an acute angle to the contact position and loading of the wiper arm in the contact direction against the window via a tension spring element that is attached to fixed articulation points on the bearing part and the wiper arm is connected, the connection on the bearing part being located behind the pivot axis starting from the wiper arm, and its line of action, determined by its connections, laterally offset to the pivot axis of the wiper arm runs and compared to this in the contact position is further offset in the direction of the disc than in the rest position, in which the wiper arm is automatically fixed in relation to the bearing part, Copy ' / 2 - 2 - Daim 15 39OA / 4 EPT br-sm characterized in that the wiper arm (1) in its rest position opposite the bearing part (3) via a support member (12, 19, 26) engaging the bearing part (3) and the wiper arm (1) is articulated, one of whose articulations one 'as a latching connection in the rest position of the wiper arm (1) formed sliding guide and the bearing part-side articulation (11, 20, 30) opposite the pivot axis (2) of the wiper arm (1) in the direction of the end of the wiper arm (1) in its Contact position is arranged offset and that in its contact position in the direction of the wiper arm (1) and in its rest position from the pivot axis (2) runs away diagonally towards the wiper arm (1). 2. wiper arm according to claim 1, characterized in that the Stützglieg of a rectangular spring clip (12) is formed, one of which is a short bracket section in an extension (10) of the bearing part (3) is articulated and the opposite bracket section when lifting the wiper arm (1) in a Latching device attached on the wiper arm engages. / 3 Daim Ί5 390A / 4 EPT br-sdhm 3. Wiper arm according to Claim 2, characterized in that that the locking device is formed by a clamp-shaped plastic clip (14). 4. Wiper arm according to claim 3, characterized in that that the plastic clip (14) cranked from a lower one End of a wiper rod (16) of the wiper arm (1) is supported. 5. Wiper arm according to claim 2, characterized in that that the locking device is formed by a link (18) in which the bracket portion is displaceable and through the bias of a detent spring can be positioned in the detent position. 6. Wiper arm according to Claim 5, characterized in that that the link (18) is formed in one piece, that it is on a cranked end portion of the wiper rod (16) is clipped on that the end portion of the wiper rod (16) forms the locking spring of the locking device, and that a the outer end of the wiper rod (16) is angled to limit the extension of the displaceable bracket section. 7. Wiper arm according to one or more of the preceding claims, characterized, that the support member of a strut (19) U-shaped transverse Daim 15 390A / 4 EPT br-schm section is formed on the one hand on the bearing axis (20) is pivotably mounted in the extension (10) and the opposite end of which is on the other hand provided with a guide pin (21) which is opposite to a spring-loaded The gate (22) is displaceable, the spring preload being provided by a free end of a wiper rod (23) is upset. 8. Wiper arm according to one or more of the preceding claims,
characterized, that the support member is formed by a twisted flat strut (26) whose end on the wiper arm is angled and is suspended in a fixed console (27) on the wiper arm side and its opposite end by means of a bolt (29) guided displaceably in a slot guide (30) of a U-shaped forked extension (31) is, wherein the bolt (29) can be locked by a detent spring (32;). 25th 30th COPY 35 / 5