DRIVE UNIT FOR MOTOR VEHICLE APPLICATIONS

Abstract

A drive unit for motor vehicle applications, in particular motor vehicle closing devices. The drive unit comprises an electric motor and at least one drive element driven by the electric motor. In addition, an actuation lever that cooperates with the drive element is provided. The drive element and/or the actuation lever are advantageously designed to be able to rotate about an axis. A rotatably mounted intermediate element is provided between the drive element and the actuation lever. According to the invention, the intermediate element is in the form of a friction-reducing rolling element.

Claims

1. A drive unit for motor vehicle application, the drive unit comprising: an electric motor and a drive element driven by the electric motor, an actuation lever cooperating with the drive element, wherein the actuation lever is rotatable about a first axis, and a rotatably mounted intermediate element positioned between the drive element and the actuation lever, wherein the intermediate element is a friction-reducing rolling element.

2. The drive unit according to claim 1, wherein the rolling element is mounted rotatably about a rolling element axis in or on the actuation lever, and the rolling element axis is different from the first axis of the actuation lever.

3. The drive unit according to claim 2, wherein the rolling element axis is oriented parallel to a surface of an actuation ramp on the drive element.

4. The drive unit according to claim 3, wherein the drive element is configured as a drive disk which is rotatable about a second axis, wherein the actuation ramp is provided on an eccentric cam.

5. The drive unit according to claim 4, wherein the actuation ramp runs on the eccentric cam in a spiral plane or a helical plane.

6. The drive unit according to claim 3, wherein the drive element is a linear actuation element that is linearly displaceable, and wherein the actuation ramp is provided on a linear actuation element.

7. The drive unit according to claim 6, wherein the linear actuation element is one of a toothed rack or a threaded spindle.

8. The drive unit according to claim 2, wherein the rolling element is cylindrical or barrel-shaped relative to the rolling element axis.

9. The drive unit according to claim 2, further comprising a pin defining the rolling element axis, wherein the pin is a separate component from the rolling element.

10. The drive unit according to claim 1, wherein the rolling element has a multilayered structure with at least one surface coating.

11. The drive unit according to claim 2, further comprising a pin defining the rolling element axis, wherein the pin is an integral component with the rolling element.

12. The drive unit according to claim 10, wherein the surface coating is at least one of a rubber coating and a plastic coating.

13. The drive unit according to claim 6, wherein the actuation lever is a push lever that linearly displaces the linear actuation element.

14. The drive unit according to claim 1, wherein the actuation lever and the drive element rotate about different axes.

15. The drive unit according to claim 2, wherein the actuation lever includes a forked holder that receives the rolling element and bears a pin that defines the rolling element axis.

16. A motor vehicle lock comprising: a locking mechanism comprising a rotary latch and a pawl; and the drive unit according to claim 1 that electrically operates the locking mechanism.

Description

[0027] The invention is explained in greater detail below with reference to drawings which show only one exemplary embodiment. In the drawings:

[0028] FIG. 1 shows a perspective view of the drive unit according to the invention in a first variant,

[0029] FIG. 2 shows the drive unit according to FIG. 1 in a side view,

[0030] FIGS. 3A and 3B show different variants of the bearing of the rolling body, and

[0031] FIG. 4 and FIG. 5 show further 2nd and 3rd exemplary embodiments of the drive unit according to the invention.

[0032] The figures show a drive unit for motor vehicle applications. In fact, the drive unit is used in a motor vehicle closing device and in particular a motor vehicle lock. For this purpose, the motor vehicle lock has a housing 1 that houses the drive unit which will be described in the following and is only suggested in FIG. 1. In the housing 1, in addition to the drive unit in question, there is a locking mechanism 2, 3 consisting of rotary latch 2 and pawls 3. This is only suggested in FIG. 2. By way of example, the drive unit ensures that the pawl 3 in the side view according to FIG. 2 is pivoted in the clockwise direction and thereby releases the rotary latch 2 which then opens in a spring-assisted manner. In other words, the locking mechanism 2, 3 is electrically opened by means of the drive unit in the present case. The drive unit described in more detail below is, however, expressly not limited to such an application, as the fields of application listed in the introduction to the description and many others make clear.

[0033] In fact, the drive unit has an electric motor 4, by means of which a drive element 5 is acted on by the electric motor 4. Under the rubric of the variants according to FIGS. 1, 2 and 5, the drive element 5 is a drive disk, while the exemplary embodiment according to FIG. 4 in this context shows a linear actuation element as the drive element 5. Correspondingly, the drive element 5 or the drive disk is rotatably mounted about an axis 6.

[0034] An actuation lever 7 interacts with the drive element 5. According to the exemplary embodiment in the figures, the actuation lever 7 is a pivot lever which is pivotably mounted about an axis 8. With reference to FIG. 2, it can be seen that the pawl 3 is connected to the actuation lever 7 coaxially with the axis 8 of the actuation lever 7 so that the pivot movements of the pawl 3 indicated in FIG. 2 and caused by the actuation lever 7 handle the previously mentioned opening of the locking mechanism 2, 3.

[0035] A rotatably mounted intermediate element 9 is provided between the drive element 5 and the actuation lever 7 which, according to the invention, is a friction-reducing rolling element 9. For this purpose, the rolling element 9 is rotatable about an axis 10 mounted in or on the actuation lever 7. The axis 10 of the rolling element 9 extends predominantly parallel to the surface of an actuation ramp 11 on the drive element 5.

[0036] In the exemplary embodiment according to FIGS. 1, 2 and 5, the actuation ramp 11 is in each case provided on an eccentric cam 12 which, starting from the axis 6 of the drive disk realized in this context, is formed on a surface side of the drive disk. In contrast, the variant according to FIG. 4, with the drive element 5 designed as a linear actuation element, has recourse to an actuation ramp 11 oriented and standing out in the longitudinal direction of the linear actuation element. In the exemplary embodiment according to FIGS. 1 and 2, the actuation ramp 11 on the eccentric cam 12 runs in a helical plane and thus has a spatial extent. Contrastingly in the exemplary embodiment according to FIG. 5, the actuation ramp 11 is formed as a spiral plane with an entirely planar extent on the associated eccentric cam 12.

[0037] The actuation ramp 11 of the drive element 5 designed as a linear actuation element of the variant according to FIG. 4 is designed as a triangular ramp in cross-section. In this case, the linear actuation element is designed overall as a toothed rack into which a worm wheel (indicated in a section in FIG. 4) on the output shaft of the electric motor 4 engages in order to be able to produce and execute the linear actuating movements indicated there in the longitudinal direction of the linear actuation element or drive element 5.

[0038] In FIGS. 3A and 3B, the rolling element 9 is shown in detail in various forms. In fact, it can be seen that the rolling element 9 is equipped with a separate pin 13 defining its axis 10, as reflected in FIG. 3B. In this case, pin 13 may be made of metal or steel, whereas the rolling element 9 may be produced of plastic. In the variant according to FIG. 3A, the pin 13 and the rolling element 9 therein are designed as a one-piece component made of plastic.

[0039] In both cases, the rolling element 9 may be equipped with a (merely suggested) surface coating 9a. As a result, the rolling element 9 typically has a multilayered structure. The surface coating 9a may be designed, for example, as a rubber coating or even plastic coatings. In the event that the rolling body 9 is made of plastic, joint production of the two layers in the sense of a two-component manufacturing process is recommended. In this case, the approach can be to produce the rolling body 9, for example, from a thermoplastic and the surface coating 9a from an elastomeric plastic simultaneously in a joint two-component plastic injection-molding process. Of course, this is only by way of example and by no means mandatory. Either way, the rolling element 9 is formed predominantly cylindrical to barrel-shaped with the central axis 10.

[0040] All of the embodiments of the actuation lever 7 according to FIGS. 3A and 3B are characterized in that the actuation lever 7 has a forked holder 7a at its head end and facing the drive element 5 for receiving and bearing the rolling body 9. For this purpose, the forked holder 7a has two fork arms which serve to bear pin 13 defining the axis 10 of the rolling body 9.

[0041] In addition, it can be seen that the rolling body 9 is predominantly designed cylindrical to barrel-shaped in cross-section with the central axis 10. In this way, the arcuate surface coating 9a can easily follow the different forms of the actuation ramp 11, and in particular the actuation ramp 11 describing the helical plane in the case of the embodiment variant according to FIGS. 1 and 2.

[0042] In this way, pressure applied to the drive element 5 always causes pressure to be applied to the rolling body 9 by the actuating ramp 11, and in the process, the actuating lever 7 executes a pivoting movement about its axis 8. This pivoting movement about the axis 8 is converted according to the exemplary embodiment in FIGS. 1 and 2 into a clockwise movement, shown in FIG. 2, of the pawl 3 which is thereby released from the rotary latch 2, which for its part opens in a spring-assisted manner. Instead of the pawl 2, the drive unit can of course work on any other conceivable actuation element which can be coupled directly or indirectly with the actuation lever 7, as described in the introduction.

LIST OF REFERENCE SIGNS

[0043] Housing 1 [0044] Rotary latch 2 [0045] Locking mechanism 2, 3 [0046] Pawl 3 [0047] Electric motor 4 [0048] Drive element 5 [0049] Axis 6 [0050] Actuation lever 7 [0051] Forked holder 7a [0052] Axis 8 [0053] Intermediate element 9 [0054] Rolling element 9 [0055] Axis 10 [0056] Actuation ramp 11 [0057] Eccentric cam 12 [0058] Pin 13