Motor vehicle door lock

Abstract

The invention relates to a motor vehicle door lock, which is equipped with a ratchet mechanism, at least one actuation lever for triggering the ratchet mechanism and a ratchet lever that is pivotable about an axis. The ratchet lever renders the ratchet mechanism ineffective, at least with regard to the magnitude and direction of occurring retarding forces, for example in the event of an accident (in the event of a crash). According to the invention the ratchet lever is mounted eccentrically on the axis thereof and thereby produces in dependence of the occurring retarding forces a counter-torque that blocks the actuation lever.

Claims

1. A motor vehicle door latch comprising: a locking mechanism, an actuation lever for triggering the locking mechanisms, wherein, when the motor vehicle door latch is subjected to an accident (crash), the actuation lever generates a first torque, and a ratchet lever pivotable around and mounted on an axis, wherein a center of mass of the ratchet lever is offset from an axis of rotation of the ratchet lever, wherein, when the ratchet lever is subject to the accident, the ratchet lever generates a counter torque that counters the first torque generated by the actuation lever which blocks movement the actuation lever as a result of the accident, wherein, when the motor vehicle door latch is subjected to the accident, both actuation lever and the ratchet lever rotate in the same direction.

2. The motor vehicle door latch according to claim 1, wherein the ratchet lever has a centre of gravity positioned above or below the axis.

3. The motor vehicle door latch according to claim 2, wherein the centre of gravity is arranged in axial elongation above or below the axis of the ratchet lever.

4. The motor vehicle door latch according to claim 3, wherein the ratchet lever contains a connected spring acting on the actuation lever in normal operation which biases the ratchet lever and which is compressed by the actuation lever in the event of the accident.

5. The motor vehicle door latch according to claim 4, wherein the ratchet lever contains a first stop against which the actuation lever moves in the event of the accident and is blocked as a result.

6. The motor vehicle door latch according to claim 5, wherein the ratchet lever is configured as a rectangular shaped lever, mounted eccentrically on the axis and containing side walls.

7. The motor vehicle door latch according to claim 6, wherein the ratchet lever is axially elongated in the direction of the locking mechanism.

8. The motor vehicle door latch according to claim 1, wherein the ratchet lever contains a connected spring acting on the actuation lever in normal operation which biases the ratchet lever and which is compressed by the actuation lever in the event of the accident.

9. The motor vehicle door latch according to claim 1, wherein the ratchet lever contains a first stop against which the actuation lever moves in the event of a crash and is blocked as a result.

10. The motor vehicle door latch according to claim 1, wherein the ratchet lever is configured as a rectangular shaped lever, mounted eccentrically on the axis and containing side walls.

11. The motor vehicle door latch according to claim 1, wherein the ratchet lever is axially elongated in the direction of the locking mechanism.

12. The motor vehicle door latch according to claim 1, wherein the actuation lever actuates a pawl.

13. The motor vehicle door latch according to claim 1, further comprising a housing and a second stop in the housing which blocks movement of the ratchet lever in a direction opposite the counter torque.

14. The motor vehicle door latch according to claim 1, further comprising a housing and a second stop in the housing which blocks movement of the ratchet lever in a direction opposite the counter torque.

15. The motor vehicle door latch according to claim 1, wherein the ratchet lever abuts the actuation lever during normal operation.

16. The motor vehicle door latch according to claim 1, wherein the actuation lever is movable relative to the axis of the ratchet lever.

17. The motor vehicle door latch according to claim 1, wherein the actuation lever and the ratchet lever together define a contact area between the actuation lever and the ratchet lever so that rotation of the ratchet lever when subjected to the accident opposes rotation of the actuation lever when subjected to the accident.

18. The motor vehicle door latch according to claim 1, wherein the locking mechanism comprises a latch, a pawl and a blocking lever.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1A and 1B show the motor vehicle door latch of the invention in an installed state (FIG. 1A) and with the ratchet lever and actuation lever removed (FIG. 1B),

(2) FIG. 2 shows the motor vehicle door lock shown in FIGS. 1A and 1B in standard operation and

(3) FIG. 3 shows a perspective detailed view onto the ratchet lever of the motor vehicle door latch in the event of a crash.

DETAILED DESCRIPTION OF THE DRAWINGS

(4) The figures show a motor vehicle door latch containing a locking mechanism 1, 2, 3 as usual. The locking mechanism 1, 2, 3 consists of a catch 1 and, in the embodiment, two pawls 2, 3. The pawl 3 carries out the actual function whilst pawl 2 is designed as a so-called comfort pawl. Pawl 3 is a blocking lever that blocks pawl 2 against catch 1 as shown in FIGS. 1A and 1B. This is, however, not important in this case as the details associated with this special embodiment are not explained further.

(5) A decisive fact is that the locking mechanism 1, 2, 3 shown, for instance, in FIGS. 1A and 1B in the main ratchet position, can be opened by the pawl 2, 3 being lifted off the catch 1. As a result, a locking boltnot expressly shownpreviously retained by the catch 1 is released so that the associated motor vehicle door can be opened. An actuation lever 4 is provided to lift the pawl 2, 3 off the catch 1 or to trigger the locking mechanism 1, 2, 3 which in the example is a triggering lever 4, although the invention is not restricted to this.

(6) It is apparent that the actuation lever or the triggering lever 4 and the pawl 2, 3 or its comfort pawl 2 are mounted on the same axis in a frame box 5. For this purpose, a bearing mandrel 6 is provided, defining said common axis.

(7) During normal operation and for triggering the locking mechanism 1, 2, 3 the actuation lever or the triggering lever 4 is pivoted, as shown in FIGS. 1A and 1B, in clockwise direction around the bearing mandrel 6 or the axis defined thereby. This is apparent from the transition between FIG. 1A, 1B to FIG. 2. As a result of the clockwise movement of the actuation levers or triggering lever 4, the pawl 2, 3 is lifted off the catch 1. During this process, the comfort pawl 2 also actually carries out a clockwise movement around the common axis 6 with the triggering lever 4. In contrast, the pawl 3 (blocking lever) is pivoted around its axis 7 in counter-clockwise direction so that the pawl 2 releases the catch 1 as apparent from the transition between FIG. 1A, 1B and FIG. 2. Normal operation corresponds to this.

(8) The further basic arrangement of the shown motor vehicle door latch also includes a ratchet lever 8, pivotably mounted around an axis 9 in the frame box 5. The axis 9 is defined by an associated bearing mandrel for the ratchet lever 8. The ratchet lever 8 ensures that the locking mechanism 2, 3 is rendered ineffective at least in the event of retarding forces F of a given magnitude and direction occurring, for instance in case of a crash. The respective retarding forces F are indicated in FIG. 3 by a respective arrow and correspond to the shown motor vehicle door latch, designed as a side door latch being subjected to a side impact on the associated side door. Such a side impact and the associated retarding forces F are predominantly exerted on the motor vehicle in Y- or transverse direction.

(9) As part of the invention, the ratchet lever 8 is eccentrically mounted on the axis 9. As a result, the ratchet lever 8 generates a counter-torque M, blocking the actuation lever or triggering lever 4 depending on the occurring retarding forces F, as schematically shown in FIG. 3. This counter-torque M acts on the ratchet lever 8 in clockwise direction in relation to its axis 9. In the event of a crash, the actuation lever or the triggering lever 4 also moves in clockwise direction around its axis 6, as indicated by respective arrows in FIG. 3. As a result, opposing movements are carried out in a contact area between the ratchet lever 8 and the actuation lever 4, as shown in FIG. 3.

(10) As soon as the actuation lever 4 leaves or threatens to leave a stop 12 on the ratchet lever 8 as a result of the already discussed bouncing movement, the stop 12 or the ratchet lever 8 can follow the actuation lever 4 as a result of the counter-torque M generated in the event of a crash. Consequently, the aforementioned bouncing does not occur. Instead, the invention ensures that, in the event of a crash, the actuation lever 4 permanently rests against the stop 12 of the ratchet lever 8 and is blocked in this way.

(11) As in the event of a crash or due to the occurring retarding forces F of a given magnitude and direction, the ratchet lever 8 maintains its position due to the intrinsic inertia, the actuation lever or triggering lever 4 cannot open the locking mechanism 1, 2, 3 in this case.

(12) In order to achieve this in detail, the ratchet lever 8 contains a centre of gravity S, located above its axis 9 in the example embodiment. This is indicated in FIG. 1A. The centre of gravity S is actually located in the axial elongation above the respective axis 9 of the ratchet lever 8. Generally, also another arrangement of the centre of gravity S, is feasible, as for instance below axis 9. This is, however not shown.

(13) FIGS. 2 and 3 show that the ratchet lever 8 contains an indicated spring 13, 14. The spring 13, 14 is actually a leg spring with two legs 13, 14, although the invention is not restricted to this. One leg 13 of the spring 13, 14 is fixed on the ratchet lever 8, whilst the actuation lever 4 rests against the other leg 14 of the spring 13, 14. The actuation lever 4 actually contains a guide arm 15, engaging in a guide recess 16 on the ratchet lever 8 with a not expressly shown journal. As a result, the journal can interact with the leg 14 of the spring 13, 14.

(14) It is apparent that the ratchet lever 8 is designed as a rectangular lever with side walls 17, eccentrically mounted on the axis 9. This means that the ratchet lever 8 has a spatial extension. The side walls 17 extending downwards from the edge of the rectangular lever or ratchet lever 8 in the direction of the frame box 5 consequently define a space in which to accommodate the spring 13, 14 arranged thereon. Also the journal of the actuation levers 4 connected to the guide arm 15, extends into this space through a guide recess 16. As a result, the respective journal can interact with the leg 14 of the spring 13, 14 as explained in more detail below

(15) In normal operation, the respective spring 13, 14 is actually acted upon by the actuation lever 4 in order to deflect the ratchet lever 8. This is apparent when comparing FIG. 1A, 1B with FIG. 2. FIG. 2 shows this normal operation, associated with the actuation lever 4 being pivoted around its axis 6 in clockwise direction and as a result, the arm 15 on the actuation lever 4 acting on the leg 14 of the spring 13, 14 via the journal. As the other leg 13 of the spring 13, 14 is securely connected to the ratchet lever 8, the ratchet lever 8 is pivoted around its axis 9 during this process. This occurs during every planned opening operation of the locking mechanism 1, 2, 3 in normal operation so that during every opening operation, the ratchet lever 8 is pivoted around its axis 9. This reliably prevents any sticking, corrosion, etc. of the ratchet lever 8.

(16) In, however, the event of the already described increased retarding forces F of a given magnitude and direction during a crash, the ratchet lever 8 remains in its position as shown in FIG. 1A. The actuation lever or the triggering lever 4 is, however, pivoted in clockwise direction around its axis 6 by the occurring retarding forces F, as shown in FIG. 3. The pivoting movement of the actuation lever or of the triggering lever 4 is stopped as soon as the actuation lever 4 moves against the stop 12 of the stationary ratchet lever 8. A prior (small) pivoting movement of the actuation lever 4 around its axis 6 causes the leg 14 of the spring 13, 14 to be slightly pivoted, so that the spring 13, 14 is thus compressed by the actuation lever 4.

(17) In order to realize the described eccentric bearing of the ratchet lever 8 in detail and to ensure that the respective centre of gravity S is arranged in the axial elongation of the axis 9 above the respective axis 9 of the ratchet lever 8, the ratchet lever 8 typically contains an extension 18, particularly apparent from FIG. 3. As a result of this extension 18, the mass distribution of the ratchet lever 8 is moved into the direction of the areas above axis 9 so that as a result, the centre of gravity S assumes the specified position above the axis 9.

(18) FIG. 3 finally only indicates a stop 19 formed on the frame box 5. The stop 19 in or on the frame box 5 or in a housing, is assigned to the ratchet lever 8. The stop 19 ensures that in case of applied retarding forces F, the ratchet lever 8 is blocked in the opposite direction shown in FIG. 3. Such retarding forces F occur in the shown example not when the side door associated with the shown motor vehicle door latch but the opposite side door is subjected to a side impact. The stop 19 is in any case arranged and aligned in such a way that any pivoting movements of the ratchet lever 8 are not impeded during normal operation, as shown in FIG. 2 and that only the ratchet lever 8 is blocked in case of said retarding forces F in the direction opposite to that shown in FIG. 3.