Lock for a motor vehicle

Abstract

A lock with a locking mechanism comprises a rotary catch, a pawl for engaging the rotary catch, a blocking lever capable of blocking the pawl if the latter is located in its catching position, and a releasing lever for opening or releasing the locking mechanism. When the releasing lever is actuated, the pawl and, if applicable, the blocking lever is moved out of its blocking position provided that the releasing lever is moved in a usual manner and the releasing lever is not exposed to increased or excessive accelerations. In case of an increased or excessive acceleration of the releasing lever such as caused by a crash or impact, an arresting device prevents the releasing lever from disengaging the pawl and optionally the blocking lever of the pawl. The arresting device is further releasable with the return of the releasing lever to the initial rest position.

Claims

1. A lock for a motor vehicle comprising: a locking mechanism with a rotatably mounted rotary catch for receiving a locking bolt, and a pawl with which the rotary catch can be engaged for retaining the locking bolt; a releasing lever for placing the locking mechanism in a disengaged state; and an arresting device for preventing the disengaged state of the locking mechanism when increased or excessive accelerations of the releasing lever occur, wherein the arresting device is releasable with a return of the releasing lever to an initial rest position; wherein the arresting device comprises an inertia lever and wherein the inertia lever and the releasing lever are interconnected in such a way that the inertia lever is moved by the releasing lever only when the releasing lever is accelerated in a usual manner with a normal acceleration; wherein the inertia lever is configured to block the pawl for preventing the disengaged state of the locking mechanism by a contour of the inertia lever which acts directly against the pawl as a stopper for the pawl; and wherein the arresting device comprises a leg spring which provides the interconnection between the inertia lever and the releasing lever such that the inertia lever is moved by the releasing lever only when the releasing lever is accelerated in the usual manner with the normal acceleration; the leg spring comprising a central portion that wraps around a rotation axis of the inertia lever, with one leg extending from the central portion and attached to the inertia lever, and another leg extending from the central portion and attached to the releasing lever.

2. The lock of claim 1, wherein the another leg of the spring rests against an outermost contour of the releasing lever in a biased manner in the initial rest position.

3. The lock of claim 1, wherein the arresting device comprises a safety lever that is moveable into a blocking position for blocking the inertia lever and wherein the safety lever is biased in a blocking direction.

4. The lock of claim 3, wherein the safety lever is movable into the blocking position which blocks movement of the inertia lever when the releasing lever is moved with the increased or excessive acceleration.

5. The lock of claim 3, wherein the arresting device is configured such that the safety lever does not reach the blocking position when the releasing lever is accelerated in the usual manner with the normal acceleration.

6. The lock of claim 3, wherein the releasing lever is configured for engagement with the safety lever via an arm of the releasing lever.

7. The lock of claim 3, wherein the safety lever is releasable from the blocking position by engagement with an arm of the releasing lever when the releasing lever is moved to the initial rest position.

8. The lock of claim 3, wherein the inertia lever has a notch or recess for engagement with the safety lever.

9. The lock of claim 3, wherein the releasing lever and the safety lever are arranged such that an interface between both has a gap when the safety lever is in the blocking position.

10. The lock of claim 1, wherein the mass of the inertia lever is several times larger than the mass of the spring.

11. The lock of claim 1, wherein the rotary catch is capable of introducing an opening moment into the pawl when the pawl is in a catching position in which the rotary catch can be engaged for retaining the locking bolt.

12. The lock of claim 1, wherein the one leg of the leg spring rests against a surface of a raised projection of the inertia lever in a biased manner in the initial rest position of the releasing lever.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a better understanding of the invention, reference should be made to the detailed description of the invention below, in conjunction with the following drawings in which like reference numerals refer to corresponding parts throughout the figures.

(2) FIG. 1 illustrates a schematic view of a locking mechanism in a rest position according to an embodiment of the invention.

(3) FIG. 2 illustrates a schematic view of a locking mechanism during normal operation.

(4) FIG. 3 illustrates a schematic view of a locking mechanism in a blocked position when the releasing lever is exposed to increased or excessive accelerations.

DETAILED DESCRIPTION OF THE INVENTION

(5) FIG. 1 illustrates a motor vehicle lock 1, according to an embodiment of the invention. The locking mechanism of the lock 1 comprises a pawl 3, a safety lever 7, an inertia lever 5 and a spring 6. The pawl 3, the inertia lever 5 and the safety lever 7 may be rotatably mounted on a metal plate 4. In addition, there is a releasing lever 2. The releasing lever 2 may be arranged above the pawl 3 and may be rotatably mounted on an axis 15.

(6) The pawl 3 may also rotate around the axis 15. The inertia lever 5 may rotate around its axis 14. The weight of the inertia lever 5 may be higher than the weight of the spring 6.

(7) The pawl 3 may block an opening rotation, in this case in clockwise direction, of a rotary catch (not shown). In FIG. 1, the pawl 3 is shown in its catching position. In order to unlock the locking mechanism, the pawl 3 has to be rotated in clockwise direction. When the pawl 3 has been moved out of its catching position, the rotary catch may be rotated clockwise in the direction of its opened position. When the rotary catch arrives at its opened position, a striker of a vehicle door or vehicle flap may leave the locking mechanism, thereby allowing the opening of a corresponding door or flap.

(8) The safety lever 7 is rotatably mounted on the axis 12. The safety lever 7 may comprise a pin 10 for engagement with the releasing lever 2 and in particular an arm 8 of the releasing lever 2. The pin 10 may extend parallel to the axis 12 so that an interface between the safety lever 7 and the arm 8 of the releasing lever 2 is provided. The safety lever 7 may be arranged adjacent to one end of the inertia lever 5. In addition, the safety lever 7 and inertia lever 5 may be configured such that the inertia lever 5 can be blocked by the safety lever 3. Accordingly, the inertia lever 5 may comprise a notch 11 or recess on one end of the inertia lever 5 in order to facilitate a reliable blocking. The blocking of the inertia lever 5 is explained in detail in connection with FIG. 3.

(9) The releasing lever 2 and the inertia lever 5 may be interconnected by a biased spring 6. A first leg 19 of the spring 12 may rest against a projection 13 of the inertia lever 5 in a biased manner. A second leg 20 of the spring 6 may rest against a contour 16 of the releasing lever 2 in a biased manner.

(10) Actuation of a corresponding grip of a vehicle connected to the locking mechanism results in a clockwise rotation of the releasing lever 2 as shown in FIG. 2. When the releasing lever 2 is actuated, the corresponding arm of the releasing lever 2 moves the second leg 20 of the spring 6 to the left via the contour 16. When the acceleration of the releasing lever 2 is normal, i.e. no increased or excessive acceleration occurs, the spring 6 acts as a rigid connection between the inertia lever 5 and the releasing lever 2. Accordingly, the movement of the releasing lever 2 in clockwise direction results in a substantially simultaneous movement of the inertia lever 5, in this case in counterclockwise direction around its axis 14. The arresting device is preferably configured such that during normal acceleration of the releasing lever 2 the safety lever 7 does not block the movement of the inertia lever 5. The safety lever 7 may be biased by a spring in the blocking direction, in this case in clockwise direction. To ensure a normal operation of the locking mechanism, the movement of the safety lever 7 may be configured such that the safety lever 7 does not engage with the notch 11 of the inertia lever 5 when the releasing lever 2 is actuated in an usual manner, i.e. with a normal acceleration of the releasing lever 2. Accordingly, the safety lever 7 may come into contact with a contour 18 of the inertia lever 5, thereby allowing a full travel of the inertia lever 5 as shown in FIG. 2.

(11) During motor vehicle collisions, parts of the door handle or other vehicle components may be exposed to large accelerations and cause a corresponding actuation of the grip resulting in an increased or excessive acceleration of the releasing lever 2. FIG. 3 illustrates the lock and the arresting device when increased or excessive accelerations of the releasing lever 2 occur. In this case, the spring 6 does not act as a rigid connection between the releasing lever 2 and the inertia lever 5 due to the mass of the inertia lever 5 and the related inertia effect. Accordingly, the inertia lever 5 basically stays stationary and does not rotate around its axis 14. The stationary inertia lever 5 preferably blocks the pawl 3 via the contour 18 which acts as a stopper. In addition, the safety lever 7 rotates in a clockwise direction and engages with the inertia lever 5 via the notch 11 to reach a blocking position as shown in FIG. 3.

(12) The blocking by the safety lever 7 prevents a further movement of the inertia lever 5, for example, caused by a bouncing releasing lever 2 or the tension of the spring 6. In the meantime, the contour 18 of the inertia lever 5 acts as a stopper for the pawl 3. The pawl 3 therefore remains in the catching position as described above preventing an unintended opening of the locking mechanism.

(13) In addition, the releasing lever 2 may comprise an arm 8 for engagement with the safety lever 7 and in particular the pin 10 of the safety lever 7. When the releasing lever 2 returns to the rest position as shown in FIG. 1, the arm 8 may carry the pin 10 of the safety lever 7 to release the blocking position of the safety lever 7. This resets the safety lever 7 so that the inertia lever 5 is free to rotate and the locking mechanism may be opened in the usual manner as described in connection with FIG. 2.

(14) The arresting device is preferably configured such that the interface between the releasing lever 2 and the safety lever 7 has a gap 17 when the safety lever 7 is in the blocking position as shown in FIG. 3. In this case, the gap 17 is arranged between the arm 8 and the pin 10 of the safety lever 7. The gap 17 may be dimensioned to allow for a predefined movement of the releasing lever 2 without affecting the safety lever 7 and thereby releasing the blocking position. This is particularly expedient as a bouncing movement of the releasing lever 2, for example, in connection with a crash and subsequent impacts, does not adversely affect the engagement between the safety lever 7 and the notch 11 of the inertia lever 5, thereby enabling a secure blocking position of the safety lever 7.

(15) An advantage of the lock of the present invention is that it reliably prevents an unintended opening of the lock caused, for example, by crashes or impacts. A further benefit of the lock is its compact arrangement with the reduced number of components. Moreover, the arresting device provides for a reliable blocking position which can only be released with the releasing lever returning to its initial rest position. In particular, bouncing movements of the releasing lever do not adversely affect the functioning of the arresting device. A further advantage is that the reduced rotation of the inertia lever in the blocked position provides for an improved pawl engagement with the rotary catch of the locking mechanism.