Motor vehicle lock

Abstract

A motor vehicle lock, preferably an electrically actuatable motor vehicle lock, comprising a locking mechanism with a rotary latch and at least one pawl, a release lever, an electric drive unit, wherein the release lever can be actuated by the electric drive unit, and the locking mechanism can be unlocked by the release lever, also comprising a release aid, wherein additional momentum for unlocking the locking mechanism can be guided into the locking mechanism by means of the release aid, the additional momentum can be generated using the electric drive unit.

Claims

1. A motor vehicle lock that is electrically actuatable, the motor vehicle lock comprising: a locking mechanism with a rotary latch and at least one pawl; a release lever; an electric drive unit, wherein the release lever is actuated by the electric drive unit and the locking mechanism is unlocked by the release lever; and a release aid, wherein additional momentum for unlocking the locking mechanism is introduced into the locking mechanism by the release aid, wherein the additional momentum is generated using the electric drive unit, wherein the release lever has a first lever arm interacting with the drive unit and a second lever arm acting on the locking mechanism, a further lever arm being provided which interacts with the release aid, the further lever arm being connected at least to the second lever arm in a non-twisting manner; wherein the electric drive unit incudes a first gear stage that interacts with the first lever arm of the release lever, and the release aid includes a second gear stage that interacts with the further lever arm, wherein the first gear stage meshes with the second gear stage; and wherein the first gear stage includes a first gear wheel and toothing that extends from the first gear wheel, the first gear wheel being positioned in a different plane of rotation from the second gear stage, and the second gear stage meshes with the toothing of the first gear stage.

2. The motor vehicle lock according to claim 1, wherein the release aid is actuated directly by the electric drive unit.

3. The motor vehicle lock according to claim 1, wherein the electric drive unit is driven in a direction opposite to that of the release lever in order to generate the additional momentum.

4. The motor vehicle lock according to claim 1, wherein the further lever arm is driven by a cam drive that is part of the second gear stage.

5. The motor vehicle lock according to claim 4, wherein the cam drive that drives the further lever arm has a freewheel to prevent movement from being introduced into the further lever arm when the release lever is operated.

6. The motor vehicle lock according to claim 1, further comprising at least one switching device that is configured to move the drive unit to a starting position.

7. The motor vehicle lock according to claim 1, further comprising a spring-loaded lever arm that is accommodated in the motor vehicle lock in a guided manner.

8. The motor vehicle lock according to claim 7, wherein the spring-loaded lever arm lever arm has a first extension that is brought into engagement with a stop and/or a control contour of a second gear stage.

9. The motor vehicle lock according to claim 8, wherein the spring-loaded lever arm has a second extension which can be brought into engagement with a further stop of the first gear stage.

10. The motor vehicle lock according to claim 9, wherein the lever arm is loaded by a compression spring in a direction of the stop and by a tension spring in a direction of the further stop.

11. The motor vehicle lock according to claim 1, wherein the pawl is disengaged from the rotary latch when the electric drive unit actuated.

12. The motor vehicle lock according to claim 1, wherein when the electric drive unit moves in a first direction of rotation, the first lever arm is actuated via the first gear stage, and the further lever arm is configured to freewheel with respect to movement of the first gear stage.

13. The motor vehicle lock according to claim 1, wherein the first gear stage and the second gear stage have a gear ratio of 1:6.

14. The motor vehicle lock according to claim 1, further comprising a switching device arranged on the second gear stage.

15. The motor vehicle lock according to claim 14, further comprising a switching cam arranged between the second gear stage and the switching device.

Description

(1) The following are shown:

(2) FIG. 1: An exemplary embodiment of an electric drive for generating a momentum on a release lever in normal operation and in emergency operation, whereby a first and a further gear stage with a lever mechanism is shown,

(3) FIG. 2: Another view of the electric drive for the operation of the release lever in a plan view,

(4) FIG. 3: A view of the first gear stage and in particular of an example of a coupling means,

(5) FIG. 4: Another view of the first gear stage with a first cam disc to actuate the first lever arm and a return spring,

(6) FIG. 5: A further three-dimensional view of the first gear stage with electric drive, return spring and first cam drive to actuate the first lever arm,

(7) FIG. 6: Another embodiment of the invention in a sketch of principle, with a spring-loaded lever arm, wherein the spring-loaded lever arm enables initialization of the gear stages.

(8) FIG. 1 shows a motor vehicle lock 1 as a dashed line. The motor vehicle lock 1 has an electric drive unit 2, a first gear stage 3, a further gear stage 4, a switching device 5 and a lever arrangement 6.

(9) The electric drive unit 2 comprises an electric motor 7 which drives a worm wheel 8. The worm gear meshes with a toothing of a first gear 9 of the first gear stage 3. The first gear wheel 9 can be operated in the direction of the arrow P by the electric drive unit 2 and the worm wheel 8. If the first gear wheel 9 is driven in the direction of arrow P, a cam 10 meshes with a first cam drive 11. The cam drive 11 is then moved in the direction of the first lever arm 12 and thus moves the lever assembly 6. The first lever arm 12 is connected in a non-twisting manner to a release lever 14 via a rotary axis 13. The release lever 14 can act directly on a locking mechanism 15. Using the release lever 14, the locking mechanism 15 can then be unlocked and the motor vehicle lock 1 can be opened.

(10) The first gearwheel 9 of the first gear stage 3 is integrally formed with a circumferential toothing 16, for example, in one piece, which meshes with the next gear stage 4. The meshing ratios between the toothing 16 and the further gear stage 4 can be clearly seen in FIG. 2. The further gear stage 4 again has a cam drive 17, which can engage with the further lever arm 18 of the lever arrangement 6. The further lever arm 18 is connected in a non-twisting manner with the lever arrangement 6 and in particular with the release lever 14.

(11) As can be clearly seen in FIG. 2, the worm wheel 8 meshes with the first gear stage and in particular with the first gear wheel 9. The first lever arm 12 is actuated or swivelled via the first cam drive 11 in order to quickly open the release lever 14 in normal operation. For this purpose, the first cam drive 11 is connected to the first gear wheel via a coupling means 19. Here, the coupling means 19 has the effect that only in the drive direction shown in FIG. 1, which is shown with the arrow P, can the first cam drive 11 be subjected to a torque or rotary motion. After the first cam drive 11 has been subjected to a release force to open the locking mechanism 15, drive unit 2 is switched off and a return spring 20 moves the first gear stage 3 back to its initial position.

(12) During this opening process, the further gear stage 4 meshes with the toothing 16. However, the rotary motion of the first gear stage 3 is selected in such a way that the rotary motion to open the locking mechanism 15 prevents the further cam drive 17 from engaging with the further lever arm 18. In addition, the cam drive 17 has a freewheel 21, which can, for example, be between 15° and 35°, preferably 25°. When the motor vehicle lock 1 is actuated normally, only the first lever arm 12 is actuated via the first cam drive 11 and the locking mechanism 15 is opened.

(13) FIG. 3 shows a detailed view of the electric drive unit 2 with the electric motor 7 and the worm wheel 8, whereby the worm wheel 8 meshes with the first gear stage 3 and in particular the first gear wheel 9. A section through the first cam drive 11 is shown so that the coupling means 19 arranged inside the first cam drive 11 can be seen. As can be clearly seen in FIG. 3, a moment is applied to the first cam drive 11 by means of the first gear 9 only when the first gear 9 moves in the direction of the arrow P, counterclockwise as shown in the example shown.

(14) If, on the other hand, the first gear wheel 9 is moved clockwise, the coupling 19 runs freely. In this case, a torque can be transmitted to the next gear stage 4 by means of the first gearwheel 9 and by means of the toothing 16. By means of the coupling means 19, it is possible to achieve very large gear ratios, since the first gear wheel 9 can be moved clockwise as often as required, without a torque being transmitted to the first cam drive 11. The first cam drive 11 runs freely when the first gear wheel 9 is actuated by means of the electric drive unit 2.

(15) FIG. 4 shows a view of the first cam drive 11 and the return spring 20. The cam 10 meshes with the first cam drive 11. The return spring 20 has reset the cam drive 11 to the start position shown in FIG. 4, so that it is possible to open the locking mechanism 15 from the start position shown.

(16) If now the first gear wheel 9 and thus the cam 10 is moved, a torque is applied to the first cam drive 11 and a first lever arm 12 can engage with the contour 22 of the first cam drive 11, so that the release lever 14 can be actuated.

(17) FIG. 5 shows the first gear stage 3 according to FIG. 4 in a three-dimensional view and in a representation swiveled towards FIG. 4. The meshing ratios between the electric drive 2 and the first gear stage 3 as well as the arrangement of a possible exemplary embodiment of a return spring 20 can be clearly seen.

(18) It should be noted that the coupling means 19 shown is not limited to the depicted design form, but that several types of couplings, such as a slipping coupling, a wrap spring coupling, etc., can also be used. The preferred coupling means allows the first gear stage 3 to actuate only the further gear stage 4 in one operating direction, so that a large transmission ratio can be achieved. The example of the design version of the invention shown here makes it possible to apply different forces to a release lever 14 with just one drive 2.

(19) FIG. 1 also shows a switching cam 23, which enables the gear stages 3 and 4 to be initialized after an emergency opening. If, in case of a temperature-induced block, contamination and/or due to an accident, the first gear 3 does not generate sufficient force, or does not provide sufficient moment to unlock the locking mechanism 15 and thus to open the motor vehicle lock 1, the further gear stage is used. In this case, a reversal of drive unit 2 is initiated by means of a control unit which, for example, evaluates a switching device on the locking mechanism. The electric motor 7 is energized in such a way that the second gear stage 4 is used. The first gear stage 3 runs freely due to the coupling means 19 and the further cam drive 17 engages in the further lever arm 18. In this case, a much higher torque can be applied to the release lever 14 via the second gear stage 4 via the further lever arm 18 and the motor vehicle lock 1 can be opened or operated with high force.

(20) In order to return the motor vehicle lock 1 and in particular the gear stages 3, 4 to the initial position, i.e., to a position from which normal operation is possible, after an emergency opening or emergency actuation, a switching device 5 on the second gear stage 4 can be provided in one design version of the invention. After an emergency actuation, the second gear stage 4 is moved until a switching cam 23 engages with the switching device 5. When the switching position of gear stage 4 is reached, gear stages 3 and 4 have assumed their initialization position, so that normal opening can be initiated. The initialization position corresponds to the starting position of the motor vehicle lock 1, as shown in FIG. 1.

(21) FIG. 6 shows in principle a further embodiment of the invention. Same parts or parts performing the same function are marked with the same reference symbols.

(22) The design according to FIG. 6 shows an alternative design for initializing the motor vehicle lock 1. A spring-loaded lever arm 24 has two extensions 25, 26. A first extension 25 works together with a stop 27, wherein the stop 27 is firmly connected with the further gear stage 4. This means that the stop 27 can exert a holding torque on the second gear stage 4, whereby a force can be applied to the extension 25 of the spring-loaded lever arm 24. In addition, the further gear stage 4 has a control contour 28, which can be meshed with extension 25.

(23) The second extension 26 can be engaged with a further stop 29 at the first gear stage 3. The further stop 29 is firmly connected to the first gear stage 3. This means that the stop 29 can exert a holding torque on the first gear stage 3, whereby a force can be applied to the extension 26 of the spring-loaded lever arm 24.

(24) The spring-loaded lever arm 24 is preferably designed in one piece. In particular, a spring-loaded lever arm 24 made of plastic can be manufactured.

(25) After an emergency actuation, initialization can take place by means of the spring-loaded lever arm 24. If an emergency actuation has taken place, the motor vehicle lock 1 must be reset to the start or starting position in order to enable normal actuation of lock 1. To do this, move or turn the second gear stage 4 counterclockwise until the stop 27 engages with the extension 25 as shown in FIG. 6.

(26) If the locking mechanism 15 is unlocked from the initialization position shown in FIG. 6, the second extension 26 engages with the further stop 29. The further stop 29 moves the spring-loaded lever arm 24 against the direction of tension of a tension spring 30 and by means of the force of a compression spring 31 over a pivot axis 32 to such an extent that the first extension 25 engages with the control contour 28. To return to the initial position, the tension spring 30 and the compression spring 31 act on the spring-loaded lever arm 24, whereby the lever arm 24 is mounted in the motor vehicle lock so that it can be guided.

(27) In accordance with the design of FIG. 6, a switching device 5 is not required for initialization, as the initial position can be safely and reproducibly reached by controlling the drive unit 2.

LIST OF REFERENCE SYMBOLS

(28) 1 Motor Vehicle Lock 2 Electric drive unit 3 First gear stage 4 Further gear stage 5 Switching device 6 Lever assembly 7 Electric motor 8 Worm wheel 9 First gear 10 Cam 11 First cam drive 12 First lever arm 13 Axis of rotation 14 Release lever 15 Locking mechanism 16 Gearing 17 Further cam drive 18 Further lever arm 19 Coupling means 20 Return spring 21 Freewheel 22 Contour 23 Switching cams 24 Spring-loaded lever arm 25 First extension 26 Second extension 27 Stop 28 Control contour 29 Further stop 30 Tension spring 31 Compression spring 32 Swivel axis P Arrow