Motor vehicle lock
09874046 ยท 2018-01-23
Assignee
Inventors
Cpc classification
Y10S292/22
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y10T292/0908
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
E05C3/06
FIXED CONSTRUCTIONS
Abstract
The invention relates to a motor vehicle lock for a motor vehicle door arrangement, wherein a catch and a pawl are provided. The catch can be brought into an opening position and into a closed position. The catch may be brought into holding engagement with a lock striker. The pawl may be brought into an engagement position. The pawl may be deflected into a release position. A pawl actuation lever is provided for deflecting the pawl. An engagement arrangement is provided. The engagement arrangement comprises a deflection lever on the side of the pawl actuation lever and a counter contour on the side of the pawl. The deflection lever is configured to engage the counter contour. An actuation movement of the pawl actuation lever can deflect the pawl into the release. An inertial characteristic of the deflection lever causes a deflection movement along a free-wheeling path.
Claims
1. A motor vehicle lock for a motor vehicle door arrangement, comprising: a catch and a pawl, which is assigned to the catch, wherein the catch can be brought into an opening position and into a closed position, wherein the catch, which is in the closed position, is or may be brought into holding engagement with a lock striker, wherein the pawl may be brought into an engagement position, in which it is in blocking engagement with the catch, wherein the pawl may be deflected into a release position, in which it releases the catch; a pawl actuation lever for deflecting the pawl into the release position; and an engagement arrangement between the pawl actuation lever and the pawl, wherein the engagement arrangement comprises a deflection lever on the side of the pawl actuation lever and a counter contour on the side of the pawl, wherein the deflection lever is configured to engage the counter contour, thereby deflecting the pawl into the release position, wherein an actuation movement of the pawl actuation lever for deflecting the pawl into the release position is translated into a deflection movement of the deflection lever, wherein an inertial characteristic of the deflection lever causes a deflection movement along a free-wheeling path, in which free-wheeling path the deflection lever misses the counter contour, when the actuation movement surpasses a rapidity threshold, and causes a deflection movement along an engagement path, in which engagement path the deflection lever engages the counter contour, when the actuation movement is below the rapidity threshold; a peg structure coupled to the deflection lever; a free-wheeling spring arrangement comprising a free-wheeling spring configured to engage the peg structure to exert a free-wheeling pre-tension force on the deflection lever towards the free-wheeling path; and an engagement spring configured to exert an engagement pre-tension force on the deflection lever towards the engagement path.
2. The motor vehicle lock according to claim 1, wherein the counter contour is arranged on a contour plate which is coupled torque-proof to the pawl and/or wherein the deflection lever comprises a corner profile for engaging the counter contour.
3. The motor vehicle lock according to claim 1, wherein the deflection movement comprises a circular movement and the deflection movement along the free-wheeling path is caused by a centrifugal force acting on the deflection lever.
4. The motor vehicle lock according to claim 1, wherein, the inertial characteristic of the deflection lever comprises the inertial mass and/or the center of mass, which inertial characteristic is configured such that it causes a deflection movement along the free-wheeling path through the centrifugal force acting on the deflection lever when the actuation movement surpasses a predetermined rapidity threshold.
5. The motor vehicle lock according to claim 1, wherein the engagement spring is arranged such that the engagement pre-tension force increases with the deflection movement of the deflection lever.
6. The motor vehicle lock according to claim 1, wherein the deflection lever is configured to pivot around a pivoting axis and the center of mass of the deflection lever is displaced from the pivoting axis.
7. The motor vehicle lock according to claim 6, wherein the pivoting axis is a deflection lever axis of the pawl actuation lever.
8. The motor vehicle lock according to claim 6, wherein the pawl actuation lever is configured to pivot around an actuation lever axis and the deflection lever is pivotably coupled to the pawl actuation lever, wherein the engagement spring exerts the engagement pre-tension force on the actuation lever axis.
9. The motor vehicle lock according to claim 1, wherein the engagement arrangement comprises a return spring arrangement configured to exert a return force on the pawl actuation lever.
10. The motor vehicle lock according to claim 9, wherein the return spring arrangement comprises a return spring which is a leg spring arranged around the actuation lever axis.
11. The motor vehicle lock according to claim 9, wherein the return spring arrangement is configured to exert a return force on the pawl actuation lever on a return protrusion of the pawl actuation lever, in a direction opposite to the deflection movement.
12. The motor vehicle lock according to claim 1, wherein a lock mechanism is provided, which may be brought into different functional states such as unlocked and locked via a lock actuation arrangement and wherein the lock mechanism acts on the deflection lever for realizing the functional states unlocked and locked such that in the functional state unlocked the lock mechanism causes a deflection movement along the free-wheeling path and in the functional state locked the lock mechanism causes a deflection movement along the engagement path.
13. The motor vehicle lock according to claim 12, wherein the engagement arrangement comprises a blocking projection configured to disengage the free-wheeling spring from the peg structure after the deflection movement has reached the disengagement distance.
14. The motor vehicle lock according to claim 12, wherein a locking lever of the lock mechanism engages a lock contour of the deflection lever for causing a deflection movement along the free-wheeling path, in particular, wherein the lock contour is arranged at a same end of the deflection lever as the corner profile.
15. The vehicle lock according to one of claim 1, characterized in that the engagement arrangement comprises a flection structure with a pair of arms comprising a first arm and a second arm, wherein the pair of arms is coupled pivotably around a flection axis and wherein the flection structure is configured to exert an internal torque on the pair of arms against a pivoting of the pair of arms from an angled neutral position in at least one pivoting direction.
16. Motor vehicle lock according to claim 15, wherein the first arm is the deflection lever.
17. Motor vehicle lock according to claim 15, wherein the second arm is a door handle lever.
Description
BRIEF DESCRIPTION OF THE FIGURES
(1) In the following, the invention will be described in an example referring to the drawings. In the drawings there is shown in
(2)
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DETAILED DESCRIPTION
(8) The motor vehicle lock 1 shown in the drawing is assigned to a motor vehicle door arrangement which comprises a motor vehicle door (not shown) beside said motor vehicle lock 1. Regarding the broad interpretation of the expression motor vehicle door, reference is made to the introductory part of the specification. Here the motor vehicle door is a side door of the motor vehicle, which is also the preferred situation.
(9) The motor vehicle lock 1 comprises the usual locking elements catch 2 and pawl 3, which pawl 3 is assigned to the catch 2. The catch 2 can be brought into an open position (not shown) and into a closed position. In the closed position shown in particular in
(10) The pawl 3 may be brought into an engagement position, shown in
(11)
(12)
(13) The phrase on the side of is used above to describe the relative positions of the deflection lever 7 and the counter contour 8 within the engagement arrangement 6, with respect to the pawl actuation lever 5 and the pawl 3. As described above, the deflection lever 7 and the pawl actuation lever 5 are on the same side of the engagement arrangement 6. Actuating the pawl actuation lever 5 causes a movement of the deflection lever 7. The movement may occur either through a direct coupling between the pawl actuation lever 5 and the deflection lever 7 or it may involve any number of intermediate parts for translating this movement.
(14) The counter contour 8 and the pawl 3 are on the same side of the engagement arrangement 6 as described above, though different than the side of the deflection lever 7. The counter contour 8 causes the pawl 3 to deflect when the deflection lever 7 engages the counter contour 8. The coupling between the counter contour 8 and the pawl 3 can be provided with a contour plate 9 as described below. In this example the contour plate 9 is next to and rotationally fixed to the pawl 3. Other options are also available for transferring movement of the counter contour 8 to the pawl 3. For example, the counter contour 8 can be provided directly on the pawl 3, or the contour plate 9 and the pawl 3 can be formed as an integral part.
(15) Further an actuation movement of the pawl actuation lever 5 for deflecting the pawl 3 into the released position is translated into a deflection movement of the deflection lever 7.
(16) In other words, actuating the pawl actuation lever 5 causes a movement of the deflection lever 7, which movement is called a deflection movement and which is, in principle, liable to move the deflection lever 7 such that it engages the counter contour 8 and thereby deflects the pawl 3 into the release position. This translation of the movement of the pawl actuation lever 5 into the deflection movement of the deflection lever 7 may occur either through a direct coupling between the pawl actuation lever 5 and the deflection lever 7 or it may involve any number of intermediate parts for translating this movement.
(17) It can be seen from
(18) The proposed motor vehicle lock 1 is now characterized in that an inertial characteristic of the deflection lever 7 causes a deflection movement along a free-wheeling path, in which free-wheeling path the deflection lever 7 misses the counter contour 8, when the actuation movement surpasses a rapidity threshold. A completed deflection movement along the free-wheeling path is shown in
(19) The proposed motor vehicle lock 1 is further characterized in that the inertial characteristic of the deflection lever 7 causes a deflection movement along an engagement path, in which engagement path the deflection lever 7 engages the counter contour 8 when the actuation movement is below the rapidity threshold. A completed deflection movement along the engagement path is shown in
(20) In this context, an inertial characteristic may refer to the inertial mass of the deflection lever 7, the moment of inertia of the deflection lever 7 or to both quantities. It may also, in addition or alternatively, refer to the center of mass of the deflection lever 7. Likewise, the rapidity threshold may be defined in terms of the speed or velocity of the actuation movement, in terms of the acceleration of the actuation movement or may in fact involve both quantities. It is also to be noted that there exists, in principle, more than one free-wheeling path and more than one engagement path. To the contrary, any path of a deflection movement which results in the deflection lever 7 missing the counter contour 8 is by definition a free-wheeling path, whereas any path of a deflection movement which results in the deflection lever 7 engaging the counter contour 8 is by definition an engagement path.
(21) As mentioned,
(22) As also mentioned,
(23) As shown in the drawings and as is also preferred, the counter contour 8 is arranged on a contour plate 9 which is coupled torque-proof to the pawl 3. Alternatively or in addition, the deflection lever 7 comprises a corner profile 10 for engaging the counter contour 8.
(24) It is also preferred that the deflection movement comprises a circular movement and the deflection movement along the free-wheeling path is caused by a centrifugal force acting on the deflection lever 7. It can be seen from the drawings that the deflection movement of the deflection lever 7 is at least partially defined by a circular movement around the actuation lever axis 11. For such a circular movement, the centrifugal force acting on the deflection lever acts to move the deflection lever 7 away from the counter contour 8. Thereby the centrifugal force acts to force the deflection lever 7 towards a free-wheeling path in cases of high rapidityas defined previouslyand less so in cases of lower rapidity.
(25) A deflection lever guide 21 may be provided to define a maximum displacement of the deflection lever 7 for the free-wheeling path. In addition or alternatively, an engagement lever guide (not shown) may be provided for limiting the displacement of the deflection lever 7 for the engagement path. Typically, the deflection lever guide 21 and the engagement lever guide are arranged on a casing, e.g. of the motor vehicle lock, around the deflection lever 7. Alternatively, either the deflection lever guide 21, or the engagement lever guide or both may be arranged on the pawl actuation lever 5, thereby providing an implementation that relies less on a fitting of tolerances.
(26) To achieve predefined behaviors at different speeds or accelerations, i.e. to engage the counter contour 8 below a certain threshold and to move along the free-wheeling path beyond the threshold, it is preferred that the inertial characteristic of the deflection lever 7 comprises the inertial mass and in addition, or alternatively, the center of mass. This inertial characteristic is configured such that is causes a deflection movement along the free-wheeling path through the centrifugal force acting on the deflection lever 7 when the actuation movement surpasses a predetermined rapidity threshold.
(27) Since it is a solid object, the deflection lever 7 has by necessity an intrinsic inertial mass and a center of mass. Both the inertial mass and the center of mass may be set to achieve the desired behavior with regard to the deflection movement path taken.
(28) The inertial mass and the center of gravity may, for example, be either set during production of the deflection lever 7, for example by choosing its dimensions and the material used, or it may also be adjusted by adding further components that add to its inertial mass. Thereby the desired behavior with relation to the predetermined rapidity threshold may be achieved.
(29) It may be advantageous to predispose the deflection lever 7 towards the engagement path. To that end, it is preferred that an engagement pre-tension force towards the engagement path is exerted on the deflection lever 7. This may preferably be implemented by having the engagement pre-tension force towards the engagement path be exerted by an engagement spring arrangement 12. In particular, this engagement spring arrangement 12 may comprise an engagement spring 12a. In this way the deflection lever 7 may be predisposed to move towards the counter contour 8, since that is the desired state in the absence of a crash state.
(30) This engagement spring 12a may be arranged such that the engagement pre-tension force increases with the deflection movement of the deflection lever 7. In other words, the engagement pre-tension force becomes larger the further the deflection lever 7 moves during its deflection movement. This is evident from the arrangement of the engagement spring 12a, which is disclosed in
(31) An advantageous arrangement for translating the actuating movement of the pawl actuation lever 5 into the deflection movement of the deflection lever 7 with desirable variability based on rapidity is realized by having deflection lever 7 be configured to pivot around a pivoting axis 13 and by having the center of mass of the deflection lever 7 be displaced from the pivoting axis 13. In that case, the rotation of the deflection lever 7 around the pivoting axis 13, which is an axis in the geometrical sense, will have the desired dependence on velocity.
(32) Further, it is preferred that the pawl actuation lever 5 is configured to pivot around an actuation lever axis 11 and the deflection lever 7 pivotably coupled to the pawl actuation lever 5. In such an arrangement, which is shown in
(33) It has proven particularly useful and is also shown in
(34) In order to ensure that the pawl actuation lever 5 is resting such that the deflection lever 7 has a defined starting point for its deflection movement, it is also preferred that the engagement arrangement 6 comprises a return spring arrangement 14 which is configured to exert a return force on the pawl actuation lever 5. Preferably, this return force is exerted on a return protrusion 20 of the pawl actuation lever 5 in a direction opposite to the deflection movement, i.e. in a direction which counteracts the deflection movement. Such a return protrusion 20 may be any structure coupled or arranged on the pawl actuation lever 5 which is suitable to be engaged by the return spring arrangement 14. A possible embodiment of such a return protrusion 20 is illustrated in
(35) For such a return spring arrangement 14, a preferred embodiment has the return spring arrangement 14 comprise a return spring 14a which is a leg spring arranged around the actuation lever axis 11.
(36) To further adjust the characteristic behavior of the deflection lever 7 on its deflection movement, in which it may take a free-wheeling path or an engagement path, it is preferred that a free-wheeling pre-tension force towards a free-wheeling path is exerted on the deflection lever 7. By having such a free-wheeling pre-tension force acting on the deflection lever 7 to move towards the free-wheeling path, it is no longer necessary to rely solely on the inertial mass of the deflection lever 7 or on the circular motion of the deflection lever 7 to achieve this effect. Preferably, such a free-wheeling pre-tension force towards a free-wheeling path is exerted by free-wheeling spring arrangement 15.
(37) Another advantageous benefit of such a free-wheeling spring arrangement 15 is that variations in the starting position of the pawl actuation lever 5, which in turn result in different lengths of the deflection movement, may be compensated by the free-wheeling spring arrangement 15. Independent of possible tolerances in the starting position of the door handle, especially however, independent of possible tolerances in the length of the Bowden cable between the door handle and the pawl actuation lever 5, the deflection lever 7 is being spring biased into a defined starting position (pivot position with respect to the deflection lever axis 13a) by the free-wheeling spring arrangement 15.
(38) Further, it is desirable that this free-wheeling pre-tension force has a smaller effect when the deflection lever 7 moves slowly in its deflection movement than when it moves rapidly. Therefore, it can be advantageous to have the deflection lever 7 be coupled to a peg structure 16 and have the free-wheeling spring arrangement 15 comprise a free-wheeling spring 15a which is configured to engage the peg structure 16 to exert the free-wheeling pre-tension force. Such a peg structure 16 may be any protrusion or element via which the free-wheeling spring 15a may exert force on the deflection lever 7. In the embodiment of
(39) Preferably, the deflection movement of the deflection lever 7 causes a relative movement between the free-wheeling spring 15a and the peg structure 16. This relative movement may then be used to modify the free-wheeling pre-tension force depending on the properties of this relative movement.
(40) For example, in the preferred embodiment which is also disclosed in
(41) This has the effect that when the deflection lever 7 moves slowly, the free-wheeling spring has more time to relax. Thus, the free-wheeling pre-tension force is reduced, thereby making it less likely that the deflection lever 7 moves along a free-wheeling path and making it more likely that the deflection lever 7 moves along an engagement path.
(42) Further, in a preferred embodiment, the deflection movement of the deflection lever 7 causes a disengagement of the free-wheeling spring 15a from the peg structure 16 after deflection movement has reached a disengagement distance. Such an arrangement also acts to have a stronger effect towards the free-wheeling path on a fast movement of the deflection lever 7 and a smaller such effect on a slower movement of the deflection lever 7.
(43) Preferably, this is achieved by having the engagement arrangement 6 comprise a blocking projection 17 configured to disengage the free-wheeling spring 15a from the peg structure 16 after the deflection movement has reached the disengagement distance. Thus, the blocking projection 17 blocks further movement of the respective leg of the free-wheeling spring 15a, thereby decoupling it from the deflection lever 7.
(44) Finally it may be economical to employ this mechanism described not only for crash safety, but also for implementing a locked or unlocked state during normal operation of the motor vehicle lock. Therefore it is preferred that a lock mechanism is provided which may be brought into different functional states such as unlocked and locked via a lock actuation arrangement and wherein the lock mechanism acts on the deflection lever 7 for realizing the functional states unlocked and locked such that in the functional state unlocked the lock mechanism causes a deflection movement along the free-wheeling path and in the functional state locked the lock mechanism causes a deflection movement along the engagement path. To this end it may be advantageous that a locking lever 18 of the lock mechanism engages a lock contour 19 of the deflection lever 7 for causing a deflection movement along the free-wheeling path. This locking lever 18 and the lock contour 19 are also disclosed in
(45)
(46) In describing the further embodiment of the proposed motor vehicle lock 1, like reference numerals will be used for like elements of the first embodiment of the proposed motor vehicle lock 1. Likewise, the following description will specify the differences of the further embodiment to the embodiment of
(47) The further embodiment of the proposed motor vehicle lock 1 aims to obviate the need for pre-tensioning the deflection lever 7, from which advantages result that will be detailed further in the following. In the further embodiment of the proposed motor vehicle lock 1, the engagement arrangement 6 comprises a flection structure 20 with a pair of arms 21,22 comprising a first arm 21 and a second arm 22. The pair of arms 21, 22 is coupled pivotably around a flection axis 23. The flection structure 20 is further configured to exert an internal torque on the pair of arms 21, 22 against a pivoting of the pair of arms from an angled neutral position in at least one pivoting direction.
(48) In other words, the first arm 21 and the second arm 22 may be pivoted relative to each other. However, the flection structure 20 is such that, when the pair of arms 21, 22 is in a certain neutral position, a torque created internally by the flection structure 20 resists such a pivoting, at least in one direction. One example for this mechanism may for example be a pair of arms 21, 22 pressed against each other with friction. In this case, relative pivoting from the starting position, which may be understood to be the neutral position, has to overcome the torque caused by friction. The neutral position is angled in the sense that first arm 21 and the second arm 22 do not form a straight line in the neutral position but are set at an angle.
(49) It is also possible that the neutral position is not restricted to a particular, single relative angle of the pair of arms 21, 22, but comprises a range of relative angles of the pair of arms 21, 22.
(50) The effect just described can be used for making the deflection lever 7 move along the free-wheeling path or along the engagement path depending on the rapidity of the actuation movement. For this, preferably the flection structure 20 is configured such that when the actuation movement surpasses the rapidity threshold, the inertial characteristic of the deflection lever 7 causes the pair of arms 21, 22 to pivot by overcoming the internal torque, thereby resulting in a deflection movement along the free-wheeling path.
(51) Likewise, it is preferred that the flection structure 20 is configured such that when the actuation movement is below the rapidity threshold, the internal torque keeps the pair of arms 21, 22 in the neutral position, thereby resulting in a deflection movement along the engagement path.
(52) Thus principally the internal torque has to be overcome to cause a deflection movement along the free-wheeling path. No external pre-tension on the pair of arms 21, 22 in the neutral position is necessary, because the internal torque only arises when an external pivoting torque is applied.
(53) It is further preferred that the flection structure 20 is configured to exert an internal torque on the pair of arms 21, 22 towards the neutral position when the pair of arms 21, 22 is at a position different from the neutral position in at least one pivoting direction. Preferably, the internal torque is exerted for any one pivoting direction. Thereby, the flection structure 20 also acts to force the pair of arms 21, 22 back into the neutral position after a deviation from the neutral position. This can be achieved, for example, by having an L-shaped, single piece element from an elastic material. Both arms of the L-shaped element may be pivoted relative to each other in either direction, but the internal torque will force them back into the L-shape in the absence of external forces.
(54) In the preferred embodiment of
(55) As a preferred way of internal engagement of such a flection structure 20, it is preferred that the pair of arms 21, 22 comprises a pair of spring pegs 25, 26 configured to engage the spring coupling 24, wherein the pair of arms 21, 22 also comprises an opening 27 for receiving a first spring peg 24 of the pair of spring pegs 25, 26. It is to be pointed out here that each arm 21, 22 need not consist of only a single elongate member, but may comprise several elongations in different directions, as demonstrated by the position of the second spring peg 26 in the further embodiment of
(56) This is particularly advantageous when, as is depicted in
(57) Preferably and according to the further embodiment, the first arm 21 is the deflection lever 7. Likewise it is preferred and also implemented in the further embodiment that the second arm 22 is a door handle lever 29. In the same way as the pawl actuation lever 5 of the embodiment of
(58) Here, the door handle lever 29 is preferably used for an indirect actuation of the pawl actuation lever 5 in the following manner. The door handle lever 29 is pivotably arranged, preferably around the flection axis 23, and configured to engage the pawl actuation lever 5 on reaching an engagement pivoting position, thereby causing the actuation movement of the pawl actuation lever 5. To this end, the door handle lever 29 comprises a door handle protrusion 30, which engages a corresponding stop surface 31 of the pawl actuation lever 5 once the door handle lever 29 has pivoted sufficiently, that pivoting position being said engagement pivoting position.
(59) The further embodiment also comprises a rest spring 32 engaging both the pawl actuation lever 5 and the door handle lever 29 via the second spring peg 26, which ensures a defined relative position between the door handle lever 29 and the pawl actuation lever 5 in the state prior to actuation of the door handle lever 29, i.e. prior to the actuation of the outer door handle.
(60) Having now described the elements of the further embodiment of
(61) Starting from the situation of
(62) Parallel to this mechanism, the door handle lever 29 engages the pawl actuation lever 5 when the door handle protrusion 30 engages the stop surface 31. Any further pivoting of the door handle lever 29 then directly translates into an actuation movement of the actuation lever 5. Since the actuation lever 5 is coupled to the deflection lever 7 at the deflection lever axis 13a, the actuation movement of the actuation lever 5 causes the deflection movement of the deflection lever 7.
(63) Depending now on the rapidity of the pivoting of the door handle lever 29, which directly translates to the rapidity of the actuation movement of the pawl actuation lever 5 once the door handle protrusion 30 engages the stop surface 31, either the torque applied to the deflection lever 7 by the omega spring 28 has enough time to pivot the deflection lever 7 against its rotational inertia on the engagement path, thereby resulting in the situation of
(64) One advantage of the further embodiment is that friction, e.g. the friction between the free-wheeling spring 15a and the peg structure 16 of the embodiment of
(65) It is preferred that the pair of arms 21, 22 is in a neutral position after completion of the deflection movement along the engagement path and engaging the counter contour 8. It is also preferred that the pair of arms 21, 22 is in a neutral position in a rest state of the engagement arrangement prior to a deflection movement of the deflection lever 7. This corresponds to the situation of
(66) By having the pair of arms 21, 22 be in the neutral position for the regular, i.e. non-crash situation, case of actuating the outer door handle, that actuation will not have to work against any force or torque from spring coupling 24 of the flection arrangement 20. This is in contrast to the embodiment of
(67) Finally it may be pointed out that the proposed solution is not only applicable to a motor vehicle lock 1 that is actuated manually by actuating a door handle. In the case that the pawl actuation lever 5 is drivable by a motor drive, a crash induced actuation of the pawl actuation lever 5 with high rapidity accordingly leads to the pawl actuation lever 5 running free as noted above.