The present invention relates to a motor vehicle lock according to the general part of claim 1 and to a motor vehicle lock arrangement with such a motor vehi- cle lock and a motorized drive according to claim 12.

The motor vehicle lock in question may be assigned to any kind of closing ele ment of a motor vehicle. Such a closing element of a motor vehicle may be a liftgate, a trunk lid, a back door, a front hood, a side door or the like. All those closing elements may be designed as pivotable or slidable closing elements.

The motor vehicle lock in question comprises two motorized functions in order to increase the user-friendliness of the motor vehicle altogether. One function is the motorized opening of the motor vehicle lock, such that the manual force needed to open the motor vehicle lock is low, independent from environmental conditions such as temperature, humidity, age of the motor vehicle or the like. The other function is the so-called“cinching-function”, which provides a motor ized closing movement of the assigned closing element just before reaching the fully closed position. This increases the user-friendliness, as this last section of the closing movement is to be performed against those forces, which are being generated by compression of the seals in this last section of the closing move ment.

The motor vehicle lock (US 6,471 ,259 B1 ), which is the starting point of the in- vention, comprises a detent mechanism with a catch and a pawl, which interact with each other in order to hold the closing element in its respective closed po sition. For this, the catch may be pivoted between an open position, a primary closed position and a secondary closed position. For the opening function, a motorized opening drive is provided. For the cinching function, a motorized cinching drive is provided. Although in case of an emergency, the cinching drive is used for the cinching-function as well as for the opening-function, the opening drive is necessary in any case for moving the cinching-drive out of the path of movement of the catch. It is therefore the object of the present invention to provide a motor vehicle lock with a cinching function and an opening function, which motor vehicle lock comprises a simple overall structure. The above noted problem is solved for a motor vehicle lock with the features of the general part of claim 1 by the features of the characterizing part of claim 1.

First of all, it is necessary that the motor vehicle lock comprises an above noted detent mechanism with a catch and a pawl, and, that the motor vehicle lock comprises a drive train arrangement with a drive element, which is to be driven in order to perform the opening function and the cinching function. Second of all, it is necessary to define a cinching sequence, which realizes the cinching function, and a release sequence, which realizes the opening function. In the cinching sequence, the catch is being driven into its primary closed position, while in the release sequence, the pawl is being driven into its release state.

Both above noted functions are realized by driving the single drive element in one and the same, predefined drive direction. The idea underlying the invention is now to use the drive element, in particular a drive movement of the drive element in the predefined drive direction, to bring the drive train arrangement into a decoupling state, when the catch is to be driven into its primary closed position in the course of the cinching sequence. In detail, it is proposed that the drive train arrangement comprises a first cou pling element with a first coupling surface and a second coupling element with a second coupling surface, that during the release sequence, the first coupling surface and the second coupling surface are in driving engagement with each other, transferring drive movements from the drive element to the pawl and that during the cinching sequence, by driving the drive element in the predefined drive direction, the drive train arrangement enters a decoupling state, in which the first coupling surface and the second coupling surface are out of driving en gagement from each other. With the proposed solution, the opening function as well as the cinching func tion may be realized with one and the same drive element, which is only to be driven in one and the same, predefined drive direction. This means, that the drive element may well be driven via a drive cable such as a bowden cable. This also means that the drive motor, that provides the motorized movement of the drive element, does only need to provide the drive motion in one single di rection. This leads to a cost effective and an especially compact mechanical ar rangement. Also in view of electrical control, the proposed solution is particu larly simple, as the motorized movements have to be generated only in one single direction by the respective motorized drive.

The expression "decoupling state" is to be understood in a wide sense. This means, that for the decoupling state it is only necessary that the first coupling surface and the second coupling surface are out of driving engagement from each other. Accordingly, the way of interaction between the two coupling ele ments is varied during the cinching sequence, such that the drive element may drive the catch into its primary closed state without preventing the pawl from moving into its engaged state. Claim 2 is directed to the pawl being raised during the cinching sequence. This is particularly advantageous in view of an emergency situation during the cinch ing sequence. Releasing the catch in such an emergency situation during at least part of the cinching sequence is not hindered by the pawl, as the pawl is being raised as noted above.

With the preferred solution according to claim 3 it is guaranteed, that the pawl is free to move into its engaged state during the cinching sequence, when the catch reaches its primary closed position or its overtravel position. The preferred embodiment according to claim 4 is directed to the cinching se quence going back on a cinching drive movement of the drive element and the release sequence going back on a release drive movement of the drive ele ment. The cinching drive movement preferably includes the release drive movement, such that the cinching sequence always goes along with a release sequence, which leads to the above noted advantage regarding an emergency during the cinching sequence. With the preferred embodiment according to claim 5, it is clarified that the drive element is coupled to the catch on the one hand and to the pawl on the other hand via two drive trains, which are at least partly different from each other. This allows to realize the motor vehicle lock with a simple construction.

The further preferred embodiments according to claims 6 and 7 are directed to a preferred constructional solution, which is based on the catch drive train, namely the drive train between the drive element and the catch, comprising a catch engagement lever.

According to the preferred embodiment of claim 8, the pawl is assigned a pawl engagement lever, which pawl engagement lever is part of the pawl drive train.

According to the further preferred embodiment of claim 9, the catch engage- ment lever and the pawl engagement lever each provide one of the coupling el ements, which allows for a particular compact mechanical construction.

Claims 10 and 11 provide particularly simple solutions to realize the decoupling state of the drive train arrangement. The only constructional requirement is the offset of the pivot axis of the drive element on the one hand and the catch en gagement lever on the other hand.

Another independent teaching according to claim 12 is directed to a motor vehi cle lock arrangement with a motor vehicle lock as noted above and with a mo- torized drive. The motorized drive is coupled to the drive element of the drive train arrangement of the motor vehicle lock in order to provide a motorized cinching sequence and a motorized release sequence as noted above. All ex planations given with respect to the first teaching are fully applicable to this second teaching.

In the preferred embodiment according to claim 13, the motorized drive is ar ranged separately from the motor vehicle lock, which allows a modular ar rangement of the motor vehicle lock arrangement. However, it may be pointed out, that the motorized drive may well be integrated into the motor vehicle lock, which provides a very compact arrangement. In the following, an embodiment of the invention is explained with respect to the drawings. In the drawings show

Fig. 1 a motor vehicle with a proposed motor vehicle lock,

Fig. 2 the motor vehicle lock according to Fig. 1 with the catch in the open po sition,

Fig. 3 the motor vehicle lock according to Fig. 1 with the catch in the second- ary closed position,

Fig. 4 the motor vehicle lock according to Fig. 1 with the catch in the primary closed position, Fig. 5 the motor vehicle lock according to Fig. 1 at the end of the release se quence,

Fig. 6 the motor vehicle lock according to Fig. 1 during the cinching sequence, Fig. 7 the motor vehicle lock according to Fig. 1 at the end of the cinching se quence.

The proposed motor vehicle lock 1 may be assigned to any kind of closing ele ment of a motor vehicle. Such a closing element of a motor vehicle may be a liftgate, a trunk lid, a back door, a front hood, a side door or the like, as noted in the introductory part of the specification.

The motor vehicle lock 1 comprises a detent mechanism 2 with a catch 3 and a pawl 4, which interact with each other in the usual way, as will be explained.

The motor vehicle lock 1 comprises a drive train arrangement 5 with a drive el ement 6. The drive train arrangement 5 is designed to transmit drive move ments from the drive element 6 to the detent mechanism 2. For this, motorized drive movements may be introduced into the drive element 6, as will be ex plained as well. The catch 3 may be pivoted around a catch axis 3a between an open position (Fig. 2), a primary closed position (Fig. 4) and a secondary closed position (Fig. 3), which secondary closed position is situated between the open position and the primary closed position. The pawl 4 may be brought into an engaged state, blocking the catch 3 in the primary closed position (Fig. 4) and in the secondary closed position (Fig. 3) and may be raised into a release state (Fig. 5) to re lease the catch 3. For this, the pawl 4 is pivotable around a pawl axis 4a.

It may be pointed out that the pawl 4 may be part of a pawl arrangement, which pawl arrangement may comprise two or more pawls, blocking each other for blocking the catch 3 in its respective closing position. The pawl 4 as such may also be designed as a two or more part component, as is shown in the draw ings. A predefined drive direction 7 is assigned to the drive element 6. In the draw ings, this predefined drive direction 7 is the clockwise direction. The drive ele ment 6 may also be moved in a reverse direction 8, which is opposite to the drive direction 7. The drive element 6 is pivotable around a drive element axis 6a.

The sequence of Fig. 6 and Fig. 7 represents the cinching sequence, which is caused by driving the drive element 6 out of its initial position in the predefined drive direction 7. In the cinching sequence, the drive train arrangement 5 enters into engagement with the catch 3 and drives the catch 3 in its closing direction 9 into its primary closed position, preferably into an overtravel position beyond the primary closed position as shown in Fig. 7. Flere and preferably, for the cinching sequence, the initial position of the catch 3 is the secondary closed position (Fig. 3), while the final position of the catch 3 is the primary closed po sition (Fig. 4).

The sequence of Fig. 4 and Fig. 5 represents the release sequence, which is caused by driving the drive element 6 out of its initial position in the predefined drive direction 7 as well. During the release sequence, the drive train arrange ment 5 enters into engagement with the pawl 4 and drives the pawl 4 in its re lease direction 10 into its release state (Fig. 5). It is essential for the invention, that in the cinching sequence, again by driving the drive element 6 in the predefined drive direction 7, the drive train arrange ment 5 enters a decoupling state (Fig. 6). For this, the drive train arrangement 5 comprises a first coupling element 5a with a first coupling surface 5a’ and a second coupling element 5b with a second coupling surface 5b’. During the re lease sequence, the first coupling surface 5a’ and the second coupling surface 5b' are in driving engagement with each other, transferring drive movements from the drive element 6 to the pawl 4, as may be extracted from the sequence of Fig. 4 and Fig 5.

It is further essential for the invention, that in the cinching sequence, by driving the drive element 6 in the predefined drive direction 7, the drive train arrange ment 5 enters a decoupling state, in which the first coupling surface 5a’ and the second coupling surface 5b’ are out of driving engagement from each other, as may be seen in Fig. 5. With the decoupling state of the drive train arrangement 5 being caused by driving the drive element 6 in the predefined drive direction 7, the cinching sequence as well as the release sequence may be realized by introducing motorized movements into the drive element 6 in only one drive di rection, which makes the resulting mechanical construction particularly simple.

Just as a matter of completeness, it may be pointed out, that the catch 3 in its closed position is in holding engagement with a lock striker 11. Flere and pref erably, the motor vehicle lock 1 is arranged at a closing element C, while the lock striker 11 is arranged at the body B of the motor vehicle. A vice versa ar- rangement is possible.

One interesting aspect of the shown embodiment is that during the cinching se quence, the pawl 4 is driven into its release state, before the catch 3 reaches the primary closed position or the overtravel position. With this it is guaranteed, that the pawl 4 does not hinder the movement of the catch 3 into the direction of its open position during an emergency situation.

Preferably, during the cinching sequence, by driving the drive element 6 in the predefined drive direction 7, the drive train arrangement 5 enters into engage ment with the catch 3 and moves the catch 3 in its closing direction, particularly into an overtravel position beyond the primary closed position, after the drive train arrangement 5 entered its decoupling state. With this it is guaranteed, that the pawl 4 may move into its engaged state during the cinching sequence, as shown in Fig. 7, without being hindered by the drive element 6. The release sequence goes back on a release drive movement 13 of the drive element 6, while the cinching sequence goes back on a cinching drive move ment 14 of the drive element 6. This is indicated in the drawings. Here it be comes apparent, that the cinching drive movement 14 includes the release drive movement 13, particularly, that the release drive movement 13 provides the start section of the cinching drive movement 14.

The drawings show, that the drive train arrangement 5 comprises a catch drive train 15 between the drive element 6 and the catch 3 and a pawl drive train 16 between the drive element 6 and the pawl 4, wherein the catch drive train 15 and the pawl drive train 16 are at least partly different from each other. Here and preferably, the two coupling elements 5a, 5b of the drive train arrangement 5 are part of the pawl drive train 16.

Various constructional embodiments for the realization of the proposed solution are possible. According to the embodiment shown in the drawings, the catch drive train 15 comprises a catch engagement lever 17, which, during the cinch ing sequence, is driven to enter into engagement with an engagement surface 18 of the catch 3, thereby driving the catch 3 into its primary closed position and, here and preferably, into the overtravel position beyond the primary closed position. The catch drive train 15 preferably comprises the drive element 6 as well as the catch engagement lever 17, which catch engagement lever 17 is pivotably coupled to the drive element 6 at a catch engagement lever axis 17a.

As noted above, when the drive element 6 is driven in its predefined drive direc- tion 7 starting from the situation shown in Fig. 3, the catch engagement lever 17 enters into engagement with the engagement surface 18 of the catch 3 (Fig. 6), thereby driving the catch 3, here and preferably, from the secondary closed po sition, into its primary closed position. In order to allow the pawl 4 to fall into its engagement state due to the force of the pawl spring 19, here and preferably, the catch engagement lever 17 drives the catch 3 into the overtravel position beyond the primary closed position. This is again shown in Fig. 7. In the displayed and insofar preferred embodiment, it is provided, that the catch engagement lever 17 comprises an output lever 17', which, during the cinching sequence, enters into engagement with the engagement surface 18 of the catch 3 (Fig. 7). The catch engagement lever 17 preferably comprises an input lever 17", which is pivotable around the catch engagement lever axis 17a and which, together with the output lever 17', establishes a knee lever mechanism. The result is a high cinching momentum at the catch 3 without the need for high driving forces. Here and preferably, the catch engagement lever 17 is a two piece component with a joint between the output lever 17' and the input lever 17", as noted above. The input lever 17" is preferably provided by the drive el ement 6 itself.

The pawl drive train 16, here and preferably, comprises a pawl engagement lever 20, which, during the release sequence, is driven to come into engage ment with an engagement surface 22 of the pawl 4, driving the pawl 4 into its release state. The pawl engagement lever 20 is pivotable around a pawl en gagement lever axis 20a, which, preferably, is arranged coaxially to the drive element axis 6a.

The coupling elements 5a, 5b may be provided by any drive component of the drive train arrangement 5. Here and preferably, the catch engagement lever 17 provides the first coupling element 5a with the first coupling surface 5a', while the pawl engagement lever 20 provides the second coupling element 5b with the second coupling surface 5b'.

During the release sequence, which is represented by the sequence of Fig. 4 and Fig. 5, the coupling elements 5a, 5b are being moved relative to each oth er, such that the coupling surfaces 5a', 5b' come out of engagement from each other. This becomes apparent from the detail view in Fig. 5. In particular, a guiding contour 21 is provided, which guides the first coupling surface 5a' out of engagement from the second coupling surface 5b' during the cinching se quence, as may again be derived from the detail view in Fig. 5. The drive element 6 is pivotable around the drive element axis 6a, while the catch engagement lever 17 is pivotable around the catch engagement lever ax- is 17a. The drive element axis 6a and the catch engagement lever axis 17a are offset from each other.

The release sequence represented by the sequence of Fig. 4 and Fig. 5 is working as follows: starting from the catch 3 being in its primary closed position (Fig. 4), the drive element 6 is being driven in its predefined drive direction 7, in Fig. 4 in the clockwise direction.

Driving the drive element 6 in its predefined direction 7 leads to the coupling surface 5a' to come into engagement with the coupling surface 5b', moving the pawl engagement lever 20 into engagement with an engagement surface 22 of the pawl 4. This results in a movement of the pawl 4 into its release state, as shown in Fig. 5. Flere it is to be noted, that the proposed solution is also interesting in terms of control technology. Fig. 2 shows, that an electric, in particular electronical, lock control 23 is provided for controlling the drive movements of the motorized drive 24, that produces the above noted drive movement of the drive element 6. When the pawl 4 has reached its release state, a pawl sensor 25 is activated, leading to stopping the motorized drive 24 by the lock control 23. With the drive train between the drive element 6 and the motorized drive 24 preferably being backdriveable, the catch 3 with its engagement surface 18, driven by the seal 12 of the closing element C, backdrives the catch engagement lever 17 and with it the drive element 6 into the direction of its initial position. The situation after completion of the release sequence is shown in Fig. 2.

The cinching sequence starts from the catch 3 resting in its secondary closed position shown in Fig. 3. Driving the drive element 6 in the predefined drive di- rection leads first of all to the drive element 6 passing the release drive move ment 13, moving the pawl 4 into the release state as noted before. In the course of the cinching drive movement 14, especially in the course of the movement section 14', here and preferably after bringing the drive arrangement 5 into its decoupling state, the catch engagement lever 17 enters into engage- ment with the engagement surface 18 of the catch 3, driving the catch 3 into the direction of the primary closed position, here and preferably into the overtravel position as shown in Fig. 7. When reaching the primary closed position and/or the overtravel position, a catch sensor 26 is activated, which causes the lock control 23 to stop the motorized drive 24. As a result, the drive element 6 is driven into its initial position mainly by its drive element spring 27.

In all embodiments, it is preferred, that the motorized drive 24 is provided, which is coupled to the drive element 6 of the drive train arrangement 5 in order to provide a motorized cinching sequence and a motorized release sequence as noted above. Such motorized drive 24 is indicated in the drawings. The mo- torized drive 24 may be an integral part of the motor vehicle lock 1 , leading to a compact overall arrangement. However, here and preferably, the motorized drive 24 is realized and arranged separately from the motor vehicle lock 1. Fur ther preferably, the motorized drive 24 is coupled to the drive element 6 via a drive cable, in particular, a bowden cable 28.

According to a second teaching, a motor vehicle lock arrangement 29 is claimed as such, which comprises an above noted motor vehicle lock 1 as well as an above noted motorized drive 24. It is essential to this second teaching, that the motorized drive 24 is coupled to the drive element 6 of the drive train arrangement 5 in order to provide a motorized cinching sequence and a motor ized release sequence. All explanations given for the motor vehicle lock 1 and its interaction with the motorized drive 24 are fully applicable to this teaching.

Preferably, the motorized drive 24 is arranged separately from the motor vehi- cle lock 1 as noted above. Further preferably, the coupling between the motor ized drive 24 and the drive element 6 comprises a drive cable and, in particular, an above noted bowden cable 28, which is indicated in the drawings by just a solid line. According to a third teaching, the motorized drive 24 for a motor vehicle lock may be provided by a closing element drive (not shown), which serves for driv ing the closing element between an opened position and a closed position of the closing element. The closing element drive is coupled to the closing ele ment on the one hand and to a drive cable, in particular a bowden cable, on the other hand. The closing element drive is assigned a mechanical linkage, which may be driven between a deployed state and a retracted state by the closing element drive, wherein the drive cable transmits a drive movement depending on its change in state.

A motor vehicle lock 1 , such as a motor vehicle lock 1 described above, may be coupled to the drive cable. In the shown embodiment, the drive element 6 may be coupled to the drive cable, such that a cinching sequence and/or a release sequence may be initiated by the closing element drive. The motor vehicle lock 1 may be brought into an opening state, into a secondary closing state and into a primary closing state.

The closing element drive comprises a drive motor, which may be driven in two drive directions, whereby the drive motor may be positioned into a number of drive positions. In order to drive the motor vehicle lock 1 into its secondary closing state, in a first step, the drive motor is driven in its first drive direction into a first drive posi tion, driving the closing element into a position, which corresponds to the sec ondary closing position of the motor vehicle lock 1. In a second step, the drive motor is again driven in its first drive direction into a second position, which leads to the mechanical linkage changing its state and thereby driving the motor vehicle lock 1 via the drive cable into its primary closed position. Finally, in a third step, the drive motor is driven in its second drive direction into a third drive position, which is arranged between the first drive position and the second drive position. Those three drive positions are stored in a motor controller and may be optimized during the operation of the proposed system. The drive positions may be represented by the respective number of rotations of a motor shaft or the like.

There are a number of advantageous constructional variants possible to realize the mechanical linkage. The linkage, for example, may comprise a sliding guide, being able to be slid between the above noted deployed and the above noted retracted state. The mechanical linkage may as well include a rotating cam, which rotation may lead to reaching the above noted deployed and the above noted retracted state. It may finally be pointed out, that the above noted third teaching is not restricted to be used in connection with the above noted motor vehicle lock 1 according to the first teaching. It is rather universally applicable to all kinds of motor vehicle locks 1 that provide a cinching mechanism, which may be driven by a drive ca- ble, like a bowden cable.