The invention is directed to a motor vehicle lock for a motor vehicle door arrangement.
The motor vehicle lock in question is assigned to a motor vehicle door arrangement which comprises at least a motor vehicle door. The expression “motor vehicle door” is to be understood in a broad sense. It includes in particular side doors, back doors, lift gates, trunk lids or engine hoods. Such a motor vehicle door may generally be designed as a sliding door as well.
The crash safety plays an important role for today's motor vehicle locks. It is of particular importance that neither crash induced acceleration nor crash induced deformation leads to an unintended opening of the motor vehicle door which the motor vehicle lock is assigned to. For example, in case of a side impact on the motor vehicle the outer door handle may be reluctant to follow the impact due to mass inertia of the outer door handle. As a result a relative movement between the outer door handle and the motor vehicle door occurs, which again may lead to an unintended opening of the motor vehicle door. Alternatively or in addition a crash induced deformation may act on the motor vehicle lock, which may again lead to an unintended opening of the motor vehicle door. The motor vehicle lock should be robust against all those crash conditions that may lead to an unintended opening of the motor vehicle door.
The known motor vehicle lock (US 2011/0181052 A1), which is the starting point for the invention, is provided with the usual locking elements catch and pawl, wherein the pawl may be deflected into a release position by actuation of a pawl actuation lever.
For deflecting the pawl into its release position, a pawl actuation lever is provided which, together with the pawl, establishes an actuation drive train for deflecting the pawl.
The motor vehicle lock comprises a switchable lock arrangement, which is located in the actuation drive train. Being in a locked state, the switchable lock arrangement blocks a drive train component, namely the pawl actuation lever. Being in an unlocked state, the switchable lock arrangement allows deflecting the pawl by an actuation of the pawl actuation lever.
To guarantee a high crash safety the switchable lock arrangement switches into the lock condition, when a predetermined crash induced acceleration occurs. As a result, during a crash, the switchable lock arrangement locks further actuation of the pawl actuation lever.
The known motor vehicle lock guarantees a high crash safety with respect to predetermined crash induced acceleration. However, during the blockage of the pawl actuation lever, a crash induced deflection of the pawl is still possible, for example due to crash induced deformation.
It is the object of the invention to improve the known motor vehicle lock such that the crash safety is increased with low constructional effort.
The above noted object is solved for a motor vehicle lock.
The proposed solution is based on the idea that the switchable lock arrangement, in its locked state, acts on two drive train components, which are located offset from one another in the actuation drive train.
According to the invention, the switchable lock arrangement being in a locked state, decouples a first drive train component from the pawl for letting an actuation of the pawl actuation lever run free without deflecting the pawl or blocks a first drive train component for blocking an actuation of the pawl actuation lever.
In addition to decoupling or blocking of the first drive train component, the switchable lock arrangement, in the locked state, is blocking a second drive train component for blocking its driving motion, which second drive train component is located in the actuation drive train offset from the first drive train component towards the pawl.
This additional measure further reduces the risk of the pawl being deflected by any drive train component which is situated between the pawl and the second drive train component.
Several embodiments lead to simple construction of the switchable lock arrangement. An embodiment, proposes a close coupling and even a combination of the coupling element and the blocking element. With this approach, various existing motor vehicle locks may be provided with the proposed solution without structural changes.
In an embodiment, the proposed motor vehicle lock may be configured such that during very fast actuation of the pawl actuation lever the switchable lock arrangement does not reach its locked state quick enough in order to deflect the pawl into its release position. This is very useful in a crash situation as crash accelerations often lead to very fast actuation of the pawl actuation lever. As the delay of the switchable lock arrangement reaching its locked state mainly goes back on mass inertia, this delay may easily be configured by choosing a corresponding weight distribution.
In an embodiment, the invention provides a motor vehicle lock for a motor vehicle door arrangement, wherein a catch and a pawl, which is assigned to the catch, are provided, 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 at least one release position, in which it releases the catch, wherein a pawl actuation lever is provided, which is coupled to the pawl establishing an actuation drive train for deflecting the pawl into a release position in a driving motion of the actuation drive train components, wherein a switchable lock arrangement is located in the actuation drive train, wherein, with the switchable lock arrangement being in an unlocked state, an actuation of the pawl actuation lever deflects the pawl and, with the switchable lock arrangement being in a locked state, a first drive train component is decoupled from the pawl for letting an actuation of the pawl actuation lever run free without deflecting the pawl or a first drive train component is blocked for blocking an actuation of the pawl actuation lever, wherein a predetermined crash condition causes the switchable lock arrangement to be in the locked state such that during the crash condition a crash induced actuation of the pawl actuation lever runs free or is blocked, wherein in the locked state, in addition to decoupling or blocking of the first drive train component, the switchable lock arrangement is blocking a second drive train component for blocking its driving motion, which second drive train component is located in the actuation drive train offset from the first drive train component towards the pawl.
In an embodiment, the predetermined crash condition is one of a predetermined crash acceleration acting on the motor vehicle lock, a predetermined crash velocity acting on the motor vehicle lock and a predetermined crash deformation acting on the motor vehicle lock.
In an embodiment, the first drive train component is the pawl actuation lever.
In an embodiment, the second drive train component is a pawl release lever coupled to the pawl.
In an embodiment, the pawl is deflectable while the pawl release lever is being blocked by the switchable lock arrangement.
In an embodiment, the second drive train component is the pawl.
In an embodiment, the switchable lock arrangement comprises a moveable blocking element, which, in the locked state of the switchable lock arrangement, is in a blocking position, in which it is in or may come into blocking engagement with a counter blocking element for blocking of the second drive train component, and which, in the unlocked state of the switchable lock arrangement, is in a non-blocking position, in which it releases the second drive train component.
In an embodiment, during the pawl actuation lever is running free due to the switchable lock arrangement being in its locked state, the blocking element is being hindered to move into its non-blocking position by a guide contour.
In an embodiment, the switchable lock arrangement comprises a first coupling lever on the side of the pawl actuation lever, a second coupling lever on the side of the pawl and a moveable coupling element that in the unlocked state is in a closing position for a coupling engagement with the two coupling levers and in the locked state is in an opening position for decoupling the two coupling levers.
In an embodiment, the coupling element and the blocking element are coupled to each other, such that moving the coupling element into the opening position goes along with moving the blocking element into the blocking position and moving the coupling element into the closing position goes along with moving the blocking element into the non-blocking position.
In an embodiment, the first coupling lever is the pawl actuation lever and that the second coupling lever is one of a pawl release lever coupled to the pawl and the pawl.
In an embodiment, the switchable lock arrangement is pretensioned into the unlocked state.
In an embodiment, deflecting the pawl actuation lever from its non-actuated state into its actuated state in normal operation causes movement of the switchable lock arrangement into the unlocked state and that deflecting the pawl actuation lever from its actuated state into its non-actuated state causes movement of the switchable lock arrangement into the locked state.
In an embodiment, deflecting the pawl actuation lever from its non-actuated state into its actuated state with a rapidity that is above a threshold rapidity, in particular induced by a crash, the pawl actuation lever runs free due to the mass inertia based delay in unlocking of the switchable lock arrangement.
In an embodiment, the pawl release lever comprises an engagement surface, which during a driving motion of the pawl release lever comes into driving engagement with a counter engagement surface on the pawl.
In an embodiment, the counter blocking element is fixed at the motor vehicle lock.
In an embodiment, the guide contour is arranged on the pawl actuation lever.
In an embodiment, the coupling element and the blocking element are fixedly coupled to each other.
In an embodiment, the coupling element and the blocking element are combined in a one piece component.
In the following the invention will be described in an example referring to the drawings. In the drawings show
The motor vehicle lock 1 shown in the drawings is assigned to a motor vehicle door arrangement, which comprises a motor vehicle door (not shown) besides said motor vehicle lock 1. Regarding the broad interpretation of the expression “motor vehicle door” reference is made to the background portion of the specification. In an embodiment, the motor vehicle door is a side door of the motor vehicle.
The motor vehicle lock comprises the usual locking elements catch 2 and pawl 3, which is assigned to the catch 2. The catch 2 can be brought into an open position (not shown) and into a closed position (
The pawl 3 may be brought into an engagement position shown in
As will be explained in further detail, the pawl actuation lever 5 is coupled to the pawl 3 establishing an actuation drive train for deflecting the pawl 3 into the release position in a driving motion of the actuation drive train components. Accordingly, such drive train components, for example, are the pawl actuation lever 5 and the pawl 3 itself.
Again,
The proposed motor vehicle lock 1 is designed such that a predetermined crash condition causes the switchable lock arrangement 6 to be in the locked state such that during the crash condition a crash induced actuation of the pawl actuation lever 5 runs free or is blocked, as noted above. Such a predetermined crash condition may be a crash induced speed, acceleration or deformation that exceeds a certain threshold. An example for switching the switchable lock arrangement 6 based on a predetermined crash condition will be described later.
It is of particular importance now that in the locked state, in addition to decoupling or blocking of the first drive train component 7, the switchable lock arrangement 6 is blocking a second drive train component 8 for blocking its drive motion, which second drive train component 8 is located in the actuation drive train offset from the first drive train component 7 towards the pawl 3.
Here the first drive train component 7 is the pawl actuation lever 5. Accordingly, switching the switchable lock arrangement 6 into the locked state leads to letting the pawl actuation lever 5 run free or blocking the pawl actuation lever 5.
Further, the second drive train component 8 is a pawl release lever 9 coupled to the pawl 3. The pawl release lever 9 comprises an engagement surface 9a, which is or may be brought into engagement with a counter engagement surface 3a at the pawl 3. Accordingly, pivoting the pawl release lever 9 in clockwise direction in
The above noted blocking of the pawl release lever 9 is advantageous in applications that require a closing motion of the catch 2, while the switchable lock arrangement 6 being in its locked state. For this closing movement of the catch 2 the pawl 3 has to be able to deflect at least slightly. However, if this freedom of movement for the pawl 3 is not necessary, it may be advantageous that the second drive train component 8 is the pawl 3 itself. The pawl 3 would most safely be secured against unintended deflection.
The switchable lock arrangement 6 comprises a movable blocking element 10, which, in the locked state of the switchable lock arrangement 6, is in a blocking position. This is shown in the detailed view of
In the unlocked state of the switchable lock arrangement 6, which is shown in
The counter blocking element 11 is fixed at the motor vehicle lock 1. This means that in the blocking position the blocking element 10 may not move to the left in
In an embodiment the blocking element 10 may not be moved into its non-blocking position as long as the pawl actuation lever 9 is running free due to the switchable lock arrangement 6 being in its locked state. Accordingly it is proposed that during the pawl actuation lever 5 is running free due to the switchable lock arrangement 6 being in its locked state, the blocking element 10 is being hindered to move into its non-blocking position by a guide contour 12, which guide contour 12 is arranged on the pawl actuation lever 5. The guide contour 12 can be aligned to a circle around the pivot axis A of the pawl actuation lever 5.
The switchable lock arrangement 6 can be realized as a switchable coupling arrangement. For this, it comprises a first coupling lever 13 on the side of the pawl actuation lever 5, a second coupling lever 14 on the side of the pawl 3 and a movable coupling element 15 that in the unlocked state is in a closing position for a coupling engagement with the two coupling levers 13, 14 (
In the unlocked state (
The coupling element 15 is arranged on one of the two coupling levers 13, 14. Releasing the pawl actuation lever 5 from its actuated state (
It may be taken from the detailed view in
In the shown embodiment the first coupling lever 13 of the switchable lock arrangement 6 is the pawl actuation lever 5 as noted above and the second coupling lever 14 is one of the pawl release lever 9 coupled to the pawl 3 and the pawl 3 itself.
The switchable lock arrangement 6 can be pretensioned into its closing state such that deflecting the pawl actuation lever 5 from its non-actuated state (
It may be seen in
According to the above the actuation of the pawl actuation lever 5 firstly comprises a release section of movement of the pawl actuation lever 5, during which the coupling element 15 is being released to move into its closing position. This first section of movement is indicated in
The first section of movement is followed by a subsequent pawl deflecting section of movement of the pawl actuation lever 5, during which the pawl 3 is being deflected into its release position if the coupling element 15 has reached its closing position during the release section of movement.
Interesting is now the aspect that the pawl actuation lever 5, while in the pawl deflecting section of movement, prevents the coupling element 15, which may still be in its opening position, from reaching its closing position. For this the pawl actuation lever 5 comprises the guide contour 12, that does not allow the coupling element 15 with its coupling surface 15a to pass into the direction of the closing position.
The mass inertia based delay regarding closing of the switchable lock arrangement 6 goes back mainly on the weight distribution of the coupling element 15. Accordingly, the delay and the above noted threshold rapidity may be configured easily just by changing the weight distribution of the coupling element 15.
In a further embodiment a lock mechanism 18 is provided, which may be brought into different functional states such as “unlocked” and “locked” via a lock actuation arrangement 19 indicated in
It may be seen in
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.