Lock for a motor vehicle

Abstract

A lock for a motor vehicle includes 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. The lock further includes a blocking lever that blocks the pawl when the pawl is located in a catching position, and a releasing lever for disengaging the locking mechanism. A first spring interconnects the blocking lever and the releasing lever, wherein the blocking lever and the releasing lever move either together or independently relative to the first spring based on a magnitude of acceleration of the releasing lever.

Claims

1. A lock for a motor vehicle comprising: a locking mechanism comprising 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 blocking lever that blocks the pawl when the pawl is located in a main catching position, wherein the blocking lever blocks the pawl by a surface of the blocking lever contacting a surface of the pawl, a releasing lever for placing the locking mechanism in a disengaged state, and a first spring that interconnects the blocking lever and the releasing lever, wherein the blocking lever and the releasing lever move together in response to a first acceleration of the releasing lever, and the releasing lever moves independently relative to the blocking lever in response to a second acceleration of the releasing lever, wherein a magnitude of the second acceleration is greater than a magnitude of the first acceleration; and a second spring which moves the blocking lever into a blocking position in which the blocking lever blocks the pawl in the main catching position.

2. The lock of claim 1, wherein the mass of the blocking lever is more than two times larger than the mass of the releasing lever.

3. The lock of claim 1, wherein the blocking lever and the releasing lever rotate around the same axis.

4. The lock of claim 3, wherein one leg of the first spring is attached to or rests against the releasing lever, and another leg of the first spring is attached to or rests against the blocking lever.

5. The lock of claim 1, wherein the rotary catch introduces an opening moment onto the pawl in at least one of a main locking position and a preliminary locking position.

6. The lock of claim 1, wherein the blocking lever comprises an elevation which acts as a stop for the releasing lever.

7. The lock of claim 1, wherein the second spring comprises a first leg which rests against the blocking lever and a second leg which rests against an arm of the pawl adjacent an axis of the pawl.

8. The lock of claim 1 comprising a third spring which enters a notch between the releasing lever and the blocking lever when the releasing lever moves independently of the blocking lever due to the second acceleration.

9. The lock of claim 8, wherein an overlapping area of the blocking lever is below an arm of the releasing lever when the arm of the releasing lever rests against an elevation of the blocking lever.

10. The lock of the claim 1, wherein the blocking lever comprises a tongue which enters a dent of the rotary catch in a preliminary locking position of the rotary catch.

11. The lock of claim 10, wherein the tongue rests against a ramp portion of the dent in the preliminary locking position.

12. The lock of the claim 1, wherein the blocking lever may block the pawl in the main catching position and in a preliminary catching position.

13. A lock for a motor vehicle comprising: a locking mechanism comprising 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; wherein the rotary catch is rotatable between a main catching position and a preliminary catching position, and the pawl engages the rotary catch in the main catching position and the preliminary catching position; a blocking lever that blocks the pawl when the rotary catch is located in the main catching position and in the preliminary catching position, and a releasing lever for causing the pawl to move out of engagement with the rotary catch in the main catching position and the preliminary catching position such that the locking mechanism is placed in a disengaged state, wherein the rotary catch introduces an opening moment onto the pawl when the pawl is in the main catching position and the preliminary catching position; wherein the blocking lever comprises a tongue which enters a dent formed in the rotary catch in the preliminary catching position.

14. The lock of the claim 13, wherein the tongue rests against a ramp portion of the dent in the preliminary catching position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a locking mechanism in its main locking position in accordance with an exemplary embodiment of the invention;

(2) FIG. 2 is a top view of the locking mechanism in its main locking position in accordance with the exemplary embodiment of the invention;

(3) FIG. 3 is a top view of the locking mechanism when the blocking lever leaves its blocking position in accordance with the exemplary embodiment of the invention;

(4) FIG. 4 is a top view of the locking mechanism when the pawl leaves its catching position in accordance with the exemplary embodiment of the invention;

(5) FIG. 5 is a top view of the locking mechanism in its opened position in accordance with the exemplary embodiment of the invention;

(6) FIG. 6 is a top view of a locking mechanism in its preliminary locking position in accordance with an exemplary embodiment of the invention;

(7) FIG. 7 is a top view of a locking mechanism in an intermediate state between the preliminary locking position and the main locking position in accordance with an exemplary embodiment of the invention;

(8) FIG. 8 is a top view of a locking mechanism as operative when excessively large accelerations manner occur, as can be caused by a crash, in accordance with an exemplary embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(9) As shown in FIG. 1, the locking mechanism of a lock includes a rotary catch 1, a pawl 2, a blocking lever 3 and a releasing lever 4 above the blocking lever 3. Rotary catch 1, pawl 2, blocking lever 3 and releasing lever 4 are rotatably mounted on a metal plate 5. The rotary catch 1 includes a fork-shaped inlet slot 6 which is formed by a load arm 7 and a catching arm 8 into which a locking bolt (not shown) enters when the corresponding door or hatch is closed. The locking bolt then turns the rotary catch 1 from an opened position in the direction of the closed position until the pawl 2 engages the rotary catch 1 in its main catching position as shown in FIG. 1.

(10) In the main catching position respectively shown in FIG. 1, the rotary catch 1 introduces an opening moment into the pawl 2. Since the pawl 2 is blocked by the blocking lever 3, the pawl 2 rests in its catching position. Thus, the blocking lever 3 has to be pivoted out of its blocking position in order to disengage the locking mechanism.

(11) The blocking lever 3 and the releasing lever 4 are interconnected by a first spring 9 (FIG. 2). One leg 10 of the first spring 9 rests against one arm 11 of the releasing lever 4 in a pre-stressed manner. The other leg 12 of the first spring 9 rests against a pin 13 of the blocking lever 3 in a pre-stressed manner. The first spring 9 is situated between the blocking lever 3 and the releasing lever 4. The blocking lever 3 and the releasing lever 4 may rotate around the same axis 14. The first spring 9 surrounds the axis 14. Therefore, the axis 14 holds the first spring 9 in its position. The first spring 9 interconnects the releasing lever 4 and the blocking lever 3 in such a manner that it is possible to remove the blocking lever 3 from its blocking position by rotating the releasing lever 4, if the acceleration of the releasing lever 4 is not excessively large. In other words, the blocking lever and the releasing lever move either together or independently relative to the first spring based on a magnitude of acceleration of the releasing lever.

(12) The mass of the blocking lever 3 is at least two times larger than the mass of the releasing lever 4. Due to the large mass of the blocking lever 3, the blocking lever 3 acts like an inertia lever as described above.

(13) As shown in FIG. 1, the arm 11 of the releasing lever 4 rests against an elevation forming a side wall 15 of the blocking lever 3 in the locking position of the lock. The side wall elevation 15 acts as a stop for the releasing lever 4. In the locking position, the side wall 15 prevents a turning movement of the releasing lever 4 in the counter-clockwise direction due to the pre-stressed first spring 9.

(14) A further pre-stressed second spring 16 includes a first leg 17 which rests against the pin 13 of the blocking lever 3, and thus against the blocking lever 3. The pin 13 is situated between the leg 12 of the first spring 9 and the leg 17 of the second spring 16. The second spring 16 includes a second leg 18 which rests against an arm 19 of the pawl 2 adjacent the axis 20 of the pawl 2. The second spring 16 is able to move the blocking lever 3 in its blocking position. Furthermore, the second spring 16 is able to keep the blocking lever 3 in its blocking position. Since the second leg 18 ends adjacent the axis 20 of the pawl 2, the spring 16 does not introduce a significant moment into the pawl 2, which prevents the pawl 2 from leaving its catching position when the blocking lever 3 is removed from its blocking position.

(15) There is a third pre-stressed spring 21. One leg 22 of the third spring 21 rests against a side wall 23 of the metal plate 5. The further leg 24 of the third spring 21 rests against an end portion of an arm 11 of the releasing lever 4. The side wall 31 is attached to the arm 26. The metal plate 5 is part of a housing.

(16) In the main locking position, a first section respectively of surface 27 of the contour of the catching lever 8 rests against an end portion of the arm 19 of the pawl 2 as shown in FIG. 1. At the same time, a contour nearby this end portion of the arm 19 rests against a surface 28 of the contour of the blocking lever nearby the end portion of the arm 26 of the blocking lever 3. As a result, the pawl 2 cannot leave its main catching position.

(17) A handle (not shown) is connected with a further arm 29 of the releasing lever 4. Activation of the handle rotates the releasing lever 4 in a clockwise manner in order to open the locking mechanism.

(18) The pin 13 is attached to an arm 30 of the blocking lever 3. A further side wall elevation 31 of the blocking lever 3 in the neighborhood of its axis 14 may act as a further stop for the releasing lever 4 in order to limit a turning movement of the releasing lever 4 relative to the blocking lever 3 in a clockwise manner.

(19) The rotary catch 1 can rotate around its axis 32. The catching lever 8 includes a second section 33 for a preliminary catching position. The second section 33 is part of the contour of the rotary catch 1.

(20) The end portion of the arm 26 of the blocking lever 3 includes a rounded tongue 25 directed toward the end portion of the catching arm 8 when the locking mechanism is in a locking position.

(21) The arm 30 of the blocking lever 3 includes a step 34 in order to provide space for the spring 16. The pawl 2 includes a second arm 35.

(22) If the corresponding handle is activated in a usual manner in order to open a corresponding door or hatch, the turning movement of the releasing lever 4 is slow. The first spring 9 does not deflect. The releasing lever 4, the first spring 9 and the blocking lever 3 rotate as a rigid member in a clockwise direction as illustrated in FIG. 3. When the blocking lever 3 has left its blocking position in accordance with FIG. 3, the pawl 2 rotates in a clockwise manner due to the opening moment introduced by the rotary catch 1. The force required to rotate the blocking lever 3 in the clockwise direction is greatly reduced as the majority of the resistance from the seal load is passed through the pawl 2 instead. Once the blocking lever 3 is disengaged from the pawl 2, the pawl 2 self opens because of a positive pressure angle between it and the rotary catch 1.

(23) The further operation in order to disengage the locking mechanism is illustrated by the FIGS. 4 and 5. FIG. 4 shows a further intermediate state. FIG. 5 shows the open state.

(24) In the intermediate state shown in FIG. 4, the arm 35 of the pawl 2 rests against the end portion of the arm 30 of the blocking lever when the pawl 2 has left its catching position. The interaction between the arm 35 of the pawl 2 and the arm 30 of the blocking lever 2 as illustrated by the FIGS. 3 and 4 makes sure that the pawl 2 leaves its catching position and will not turn back in the course of the opening operation. As a result, for example, dust or ice cannot prevent the pawl from leaving its catching position. In other words, the interaction between the arm 35 of the pawl 2 and the arm 30 of the blocking lever 2 serves as backup in order to remove the pawl from its catching position, if the opening moment is not sufficient for some reason. For this reason, the contour of the arm 35 and the contour of the end portion of the arm 30 run in such a ramp-like manner that the pawl 2 will rotate in a clockwise manner due to a rotation of the blocking lever 3, as well as due to the described interaction between the two arms 30 and 35.

(25) FIG. 5 shows the rotary catch 1 in its opened position. The arm 19 of the pawl 2 rests against the contour of the end portion of the catching arm 8 of the rotary catch 1 due to the pre-stressed spring 16 (not shown in FIG. 5). The pre-stressed spring 16 causes in addition that the arm 26 of the blocking lever 3 rests against the end portion of the arm 19 of the pawl 2.

(26) Starting from the opened position shown in FIG. 5, rotation of the catch 1 in a counter-clockwise manner results that the pawl 2 engages the rotary catch in its preliminary locking position as shown in FIG. 6. Then, the tongue 25 enters the recess or dent 36 in the end portion of the catching arm 8 due to the pre-stressed second spring 16 (not shown in FIG. 6). In addition, the arm 19 of the pawl 2 enters its preliminary catching position as shown in FIG. 6. The second section 33 of the catching arm 8 rests against the end portion of the arm 19 of the pawl 2 so that the rotary catch 1 cannot rotate back in its opened position. In addition, the end portion of the arm 19 of the pawl 2 rests against the contour 28 nearby the end portion of the arm 26 of the blocking lever 3. The blocking lever 3 blocks the pawl 2 in its preliminary catching position. As a result, the pawl 2 cannot leave its preliminary catching position. In the preliminary position, the rotary catch introduces an opening moment into the pawl 2. For this reason, it is sufficient to remove the blocking lever 3 from its blocking position as shown in FIG. 6 in order to open the locking mechanism.

(27) In the preliminary locking position, the tongue 25 rests against a ramp like portion 37 of the recess or dent 36. Due to the ramp like portion 37, rotation of the rotary catch 1 in a counter-clockwise manner causes the blocking lever 3 to leave its blocking position. Afterwards, the locking mechanism can be brought into its main locking position.

(28) As referenced above, the blocking lever and the releasing lever move either together or independently relative to the first spring based on a magnitude of acceleration of the releasing lever. If in a locking position (preliminary locking position or main locking position) excessively large accelerations of the releasing lever 4 in a clockwise manner occur, as can be caused by a crash, then the releasing lever 3 is not moved together with the blocking lever 4 due to the large inertial mass of the blocking lever 3, as illustrated in FIG. 8. A gap or notch 38 results due to the movement of the releasing lever 4 between an end portion of the arm 26 of the blocking lever 3 and an end portion of the arm 11 of the releasing lever 4. When the notch 38 occurs, a bended end portion of the leg 24 of the pre-stressed third spring 21 enters the gap 38 as shown in FIG. 8. As soon as the bended end portion of the leg 24 has entered the notch 38, the blocking lever 3 cannot leave its blocking position. Then, the bended end portion of the leg 24 of the pre-stressed third spring 21 acts as a detent.

(29) The end portion of the arm 26 of the blocking lever 3 includes an overlapping area 39. When the arm 11 of the releasing lever 4 rests against the side wall or elevation 15 of the blocking lever, the overlapping area 39 is completely below the arm 11 of the releasing lever 4. As a result, the bended end portion of the leg 24 of the third spring 21 cannot displace the arm 11 in such a manner that the notch 38 occurs.

(30) If the operation of the releasing lever 4 is fast, the torque of the third spring 21 is insufficient to overcome the mass moment of inertia of the blocking lever 3. The first spring 9 deflects uncoupling the releasing lever 4 from the blocking lever 3. The relative movement of the releasing lever 4 uncovers the detent notch 38 in the blocking lever 3. The third spring 21, constrained in the housing of the lock, is allowed to expand into this notch 38. The moving leg 24 of the third spring 21 is then in shear with the fixed housing formed by the side wall 23 and the blocking lever 3. The shear force is only the counteraction of the third spring torque with no component of the crash load in this design. Continued operation of the releasing lever 4 only results in winding up the third spring 21.

(31) The inertia mechanism is now latched in a locked state. The blocking lever 3 is not subjected to subsequent oscillations of the release chain throughout the remainder of the acceleration event. If the inertia lock is set unintentionally or there is no damage to the release chain, the spring is reset by cycling the locking mechanism.

(32) Further benefits and improvements of the invention are: Reduced number of components; Reduced package size; Reduced overall mass; Reduced handle travels and efforts (free comfort with every active latch); Safer positive latching of the inertia mechanism (bounce blocker); Bounce blocker is not subjected to crash loads; Flat stampings; Only one special metallic component required (inertia mass pawl); Reduced number of components involved in resisting crash loads; Plug and play for existing latch foot prints.

(33) The reference signs have the following meaning: 1: rotary catch 2: pawl 3: blocking lever 4: releasing lever 5: metal plate 6: fork-shaped inlet slot of the rotary catch 7: load arm of the rotary catch 8: catching arm of the rotary catch 9: first spring 10: leg of the first spring 11: arm of the blocking lever 12: leg of the first spring 13: pin of the blocking lever 14: axis 15: side wall 16: second spring 17: leg of the second spring 18: leg of the second spring 19: arm of the pawl 20: axis of the pawl 21: third spring 22: leg of the third spring 23: side wall of the metal plate 24: leg of the third spring 25: tongue of the blocking lever 26: arm of the blocking lever 27: section of a contour 28: section of the contour of the blocking lever 29: arm of the releasing lever 30: arm of the blocking lever 31: elevation of the blocking lever 32: axis of the rotary catch 33: second section of the contour of the rotary catch 34: step of the blocking lever 35: arm of the pawl 36: dent of the rotary catch 37: ramp like portion of the dent 38: notch 39: overlapping area

(34) Although the invention has been shown and described with respect to certain preferred embodiments, it is understood that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the following claims.