Lock, in particular tailgate lock, for a motor vehicle

Abstract

The invention relates to a lock (1) for a motor vehicle, comprising a locking mechanism (2) that includes a rotary latch (4) and at least one pawl (5), by means of which the rotary latch (4) can be locked in a prelocking position and a main locking position, and a shutting and opening drive (3), by means of which the locking mechanism (2) can be moved from a prelocking position into a main locking position, said movement being performed using an adjustable torque; once the locking mechanism (2) has been unlocked, the pawl (5) can be maintained in a disengaged position by means of the shutting and opening drive (3).

Description

[0001] P22057WO 1 November 15, 2023 Description Lock, in particular a tailgate lock, for a motor vehicle The invention relates to a lock, in particular a tailgate lock, for a motor vehicle having a locking mechanism with a rotary latch and at least one pawl, wherein the rotary latch can be locked in a pre-locking position and a main locking position by means of the pawl, a closing and opening drive, wherein the locking mechanism can be transferred from a pre-locking position to a main locking position by means of the closing and opening drive, and wherein the transfer takes place by means of a variable torque. In today's motor vehicles, more and more electrically assisted operating and / or functional elements are being installed. These electrically assisted assistance systems make it easier for the user to operate the motor vehicle or, for example, to make getting in and out easier.The invention relates to a motor vehicle locking device, such as can be used, for example, in doors or hatches. It is already common practice today for these locking devices to be equipped with electric drives that enable the door or hatch to be opened and / or closed electrically. The words “lock”, “motor vehicle lock”, and “locking device” are used synonymously below and refer to a locking device with which a component movably arranged on the motor vehicle can be securely held in a position during operation. P22057WO 2 November 15, 2023 A motor vehicle lock with an electric drive is known from DE 10 2009 020 488 A1. Such a motor vehicle lock usually has a rotary latch that includes at least one main catch. In the closed position, the rotary latch engages a striker orinto a lock holder that is attached, for example, to a vehicle body. The rotary latch engages with a pawl, which secures the rotary latch in the main position against rotation, preferably by means of a positive locking mechanism. The motor vehicle lock further comprises an electromotive drive unit. Functional elements of the drive unit act on the rotary pawl of the motor vehicle lock via a pawl mechanism. This allows the pawl to be moved with the drive element about a rotational axis of the pawl, whereby, for example, the rotary latch can be unlocked. To secure the position of the functional elements, the document discloses friction contacts that secure the holding position of the functional elements when the drive element is switched off. A closing and opening device for a motor vehicle lock is known from DE 10 2013 106 672 A1.The closing and opening device is equipped with a drive and a transmission element. A locking mechanism is also implemented. The drive operates with the transmission element interposed on the locking mechanism to open or close it. By means of the closing drive, the locking mechanism can be transferred from a pre-locking position to a main locking position, with the transfer taking place by means of a variable torque. In the locking systems or motor vehicle locks according to the invention, locking mechanisms are used that have a pre-locking position and a main locking position. In other words, a locking mechanism consisting of a rotary latch and at least one pawl is inherent in the locking system.To close a tailgate, for example, and particularly when closing a tailgate electrically, the tailgate moves into the area of ​​a lock holder, with the locking system and the lock holder working together. Typically, when the tailgate is closed, the locking system first moves into the pre-lock position, in which the rotary latch is held by the pawl. The locking mechanism can then be moved into the main locking position using the closing drive. When the locking mechanism is opened, the pawl is also released from the rotary latch using the electric drive, so that the rotary latch is released and the tailgate can be opened or opened electrically. Depending on the load acting on the locking mechanism, a more or less loud opening noise can be heard when the pawl is released from the rotary latch. This opening noise is also referred to as an opening bang.One aim of automobile manufacturers as well as the developers of locking systems is always to make the opening noise as quiet as possible, which in turn generates a quality feature for the operator. This is where the invention comes in. The object of the invention is to provide an improved motor vehicle lock. Furthermore, the object of the invention is to provide a motor vehicle lock in which a secure electrical opening of a locking system can be realized using the simplest design means. This object is achieved by the features of independent patent claim 1. Advantageous embodiments are specified in the subclaims. It is pointed out that the exemplary embodiments described below are not restrictive; rather, any desired variations of the features described in the description and the subclaims are possible.According to claim 1, the object of the invention is achieved in that a lock, in particular a tailgate lock, for a motor vehicle is provided, comprising a locking mechanism with a rotary latch and at least one pawl, wherein the rotary latch can be locked in a pre-locking position and a main locking position by means of the pawl, a closing and opening drive, wherein the locking mechanism can be transferred from a pre-locking position to a main locking position by means of the closing and opening drive, and wherein the transfer takes place by means of a variable torque, and wherein the pawl can be held in a release point after the locking mechanism has been unlocked by means of the closing and opening drive. A release position is characterized in that the pawl is pivoted so far out of the engagement area with the rotary latch that the pawl cannot fall back into the rotary latch contour of the main locking or pre-locking position.The lock according to the invention thus offers the advantage that the closing and opening drive comprises a multiple function. On the one hand, the closing and opening drive can be used to electrically unlock, i.e., open the locking mechanism. Furthermore, it is possible to move the locking mechanism from the initial position to the main position. As a further function of the closing and opening drive, a securing function can be implemented using the closing and opening drive. The securing function includes holding the pawl in the release position. P22057WO 5 November 15, 2023 When the release position is referred to according to the invention, this means the position of the pawl in which the pawl is located after the locking mechanism has been unlocked. To unlock, the pawl is pivoted by an electric motor so that the pawl is released from the rotary latch.The pawl is held in this release position until the rotary latch has reached its open position. If, according to the invention, reference is made to a lock for a motor vehicle, this refers to locks or locking systems that are used in motor vehicles. These can be locking systems for hoods, side doors, sliding doors, tailgates, covers or other locking systems in motor vehicles that are used wherever pivoting or displaceable components must be securely positioned and held in place by means of a locking mechanism during operation of the motor vehicle. The terms "lock", "locking system" or "motor vehicle lock" are used synonymously. The lock has a locking mechanism with a rotary latch and at least one pawl. Pawls can be used here, which interact with the rotary latch in different ways.It is conceivable that, for example, a closing or an opening moment is present in a main locking position, so that in the event of an opening moment, the pawl can additionally be held securely in the main locking position by an auxiliary pawl or a locking lever or a blocking lever. The locking mechanism according to the invention has a pre-locking position and a main locking position. When a side door, for example, is closed for the first time, the locking mechanism, in interaction with a lock holder, moves into a pre-locking position. From this pre-locking position, the locking mechanism or the rotary latch can be moved into the main locking position by means of the closing drive. The closing drive acts directly on the rotary latch and moves the rotary latch from a pre-locking position to the main locking position. In the main locking position, the pawl rests against a main notch of the rotary latch.According to the invention, the closing and opening drive has a mechanism or structure that can introduce a variable torque into the rotary latch. The variable torque offers an advantage, particularly when closing, in that when closing a side door, for example, the forces required during the transition from the preliminary detent to the main detent increase significantly. The increasing forces required during closing are due to the fact that the door must be moved against the resistance of the door seal. To ensure secure closing of the locking mechanism, and in particular secure closing when the locking mechanism is closed electrically, the locking mechanism is moved beyond the main detent position into an overtravel position. This overtravel position is characterized by the fact that the pawl can engage safely because the rotary latch has been pivoted beyond the main detent position.In the overtravel position, the locking surfaces between the pawl and the rotary latch are thus spaced apart from one another. An advantageous development of the invention is characterized in that the closing and opening drive has a cam disk, and that a control contour is arranged on the cam disk. The closing drive has at least one cam disk that can be driven by an electric motor. P22057WO 7 November 15, 2023 For this purpose, a gear can additionally be arranged between the electric motor and the cam disk so that sufficient force or torque can be provided. The cam disk itself has a control contour into which a closing pawl or a drive lever can engage directly.For this purpose, the drive lever can, for example, be pivotally mounted in the motor vehicle lock, so that the drive lever can generate an additional transmission with respect to the closing pawl. In any case, the drive lever or the closing pawl is guided in the control contour of the cam disc, so that a transfer of the rotary latch from a pre-locking position to a main locking position can be guaranteed. The cam disc and the control contour are preferably made of a plastic. The drive lever and the closing pawl, on the other hand, are preferably formed from a metallic material, in particular sheet steel. The control contour can be used to initiate a targeted transmission of a variable torque to the closing pawl. According to a further development, the cam disc interacts with a drive lever, wherein closing can be carried out by means of the drive lever.The drive lever is mounted separately in the vehicle lock and can pivot within the vehicle lock. The drive lever is preferably mounted on a lock case of the vehicle lock. On one side, the drive lever engages the control contour of the cam disc via a guide pin, for example, and on the opposite side of the bearing, the drive lever is connected to the closing pawl. By using the drive lever, a favorable transmission ratio and an optimized arrangement of the bearing of the closing pawl in the vehicle lock can be achieved. The drive lever can interact with the control contour, for example, via a stepped mandrel or via a rotatable sleeve on the drive lever. By using a sleeve, friction losses between the drive lever and the control contour can be compensated.If the locking pawl can be held in the release position by means of the closing and opening drive until the rotary latch is in the open position, this results in a further embodiment of the invention. The rotary latch is in the open position when the rotary latch is able to accommodate the lock holder. When a motor vehicle lock is open, the rotary latch is open so far that an inlet area of ​​the rotary latch, the so-called inlet mouth, is aligned in such a way that a lock holder attached to the vehicle or to a hatch can engage in the inlet area of ​​the rotary latch. During electrical opening, the closing and opening drive moves the locking pawl far enough that the locking pawl releases the rotary latch. Usually, a spring acting on the rotary latch in the opening direction is sufficient to move the rotary latch into the open position.In addition, sealing pressure from the hatch or door acts on the rotary latch, which also exerts a force on the rotary latch and forces or moves the rotary latch into the open position. Now, it can happen that, for example, in the case of a tailgate lock, a load is placed on the tailgate, such as during heavy snowfall, so that the forces acting on the rotary latch are insufficient to move the rotary latch into the open position. Depending on the load on the hatch, it can then happen that the rotary latch remains in a position in which the pawl would be able to fall back into the pre-locking position, for example. By keeping the pawl in the release position, unintentional locking of the locking mechanism can be prevented.In order to achieve an additional safety feature and to ensure that the position of the rotary latch is clearly determined, it can be advantageous if a switching device, in particular a microswitch or a Hall sensor, can detect the position of the rotary latch, and in particular the open position of the rotary latch. Microswitches are advantageously used to query the position of the rotary latch, as this provides a reliable means of position detection. A control cam is arranged on the cam disc, with the cam disc including the control cam preferably being made of a plastic and in one piece. It can be advantageous if the drive lever can be guided in the control cam. The cam disc therefore serves to move the drive lever, with the drive lever interacting directly with the closing pawl, or the closing pawl being pivotally mounted on the drive lever.The closing mechanism thus consists of an electric motor, an optionally connected gear unit, the cam disc with the control cam, the drive lever, and the closing pawl. This design makes it possible to implement a compact design of the closing mechanism within the lock and to provide an adjustable and defined closing torque through the selection of the gear unit, the design of the control cam on the cam disc, the transmission ratio of the pivotally mounted drive lever, and the arrangement of the closing pawl in relation to the rotary latch. P22057WO 10 November 15, 2023 In addition to closing, the cam disc is responsible for the task or function of electrically opening the locking mechanism. A locking mechanism is said to be electrically opened when the pawl is moved out of engagement with the rotary latch. This can refer to the pre-locking as well as the main locking position of the locking mechanism.If the pawl has an extension and the extension can be brought into engagement with the cam disc, this results in a further embodiment of the invention. For electrical opening, the cam disc interacts directly with the extension on the pawl. In this case, the drive lever does not move or is guided in the cam disc in such a way that no movement is initiated in the drive lever. In other words, the control cam on the cam disc has a contour that corresponds to a radius or a length of the drive lever from the bearing point to the point of engagement in the control cam. Thus, although the drive lever is held in the control cam, no movement is initiated in the drive lever.The extension on the pawl is designed such that the extension engages with the cam disc and, in the event of a movement opposite to the closing movement, can move the pawl into the release position. For electrical opening and closing, the cam disc thus moves in different directions relative to a bearing point or pivot point of the cam disc. In a further design variant, the cam disc has a raised portion that interacts with an engagement surface on the pawl, in particular the extension. By forming a raised portion on the cam disc, secure and easy interaction between the pawl and the cam disc can be achieved. P22057WO 11 November 15, 2023Even though a raised portion on the cam disc is mentioned in this exemplary embodiment, it is of course also possible for the extension to rest directly with its engagement surface on an outer contour of the cam disc. In any case, the cam disc interacts directly with the cam disc via the extension on the pawl. The extension has the task of providing sufficient torque to open the locking mechanism, even in extreme situations. Particularly in the event of extreme temperatures, contamination and / or, for example, if the vehicle is decelerated as a result of an accident, the electric drive and an appropriate transmission ratio must be able to provide sufficient force or torque to open the locking mechanism.The extension acts as a lever, providing a suitable transmission ratio for unlocking the locking mechanism. It can also be advantageous if the extension is made, at least in part, of plastic. Plastics have the property that they are easily moldable and can be manufactured in almost any shape, while also being lightweight. Thus, the mechanism for electrical opening can be realized with minimal weight. The pawl itself is made, at least in part, of steel, and in particular of a stamped steel sheet, since the locking mechanism—i.e., the rotary latch and pawl—must be able to hold a high load, particularly in the event of an accident.The inventive design of the motor vehicle lock now makes it possible to provide a high level of functionality with minimal construction resources. In particular, the functions of closing, electrically opening, and holding the pawl in the release position can be realized by means of a cam disk. This provides a high level of functionality with simultaneous high functional reliability in the motor vehicle lock. The invention is explained in more detail below with reference to the attached drawings using a preferred exemplary embodiment. However, the basic principle applies that the exemplary embodiment does not limit the invention, but merely represents an advantageous embodiment of the invention. The features shown can be implemented individually or in combination with other features of the description and the patent claims.It shows: Figure 1 is a schematic representation of a motor vehicle lock with a locking mechanism in a main position and a closing and opening drive, Figure 2 is the locking mechanism in an unlocked state, wherein the locking mechanism was unlocked by means of the closing and opening drive, P22057WO 13 November 15, 2023 Figure 3 is the opened locking mechanism and a holding position as a function of a storage lever for the pawl, and Figure 4 is the initial position of the closing and opening drive and the position of the locking mechanism before the motor vehicle lock is closed. Figure 1 shows the tailgate lock 1, as well as a locking mechanism 2 and a closing and opening drive 3. The locking mechanism 2 comprises a rotary latch 4 and a pawl 5, wherein the locking mechanism 2 interacts with a lock holder 6 and is shown in a main position.In the main locking position, the rotary latch 4 is held in a main notch 7 by the pawl 5, with the pawl 5 resting against the main notch 7 of the pawl 4. The tailgate lock 1 is thus in a closed position, i.e., for example, in a closed tailgate position. The closing and opening drive 3 comprises an electric drive in the form of an electric motor 8, a cam disc 9, a drive lever 10, and, as shown, a closing pawl 11. A gear (not shown), for example a worm gear and / or spur gear, can be arranged between the electric motor 8 and the cam disc 9. A control cam 12 is formed on the cam disc 9 and interacts with the drive lever 10, for example, via an engagement sleeve 13.Figure 1 shows the starting position, i.e. the main detent position, in which the motor vehicle lock 1 is located when, for example, a tailgate is closed, i.e. the locking mechanism 2 with the lock holder 6 is in the main detent position and the vehicle is ready for operation. P22057WO 14 November 15, 2023 The pawl 5 rests against an outer surface contour 14 of the rotary latch 4, so that further engagement of the pawl 5 into the main detent 7 can be limited. In addition, the pawl 5 has an extension 15 that interacts with the cam disk 5. As can be seen from Figure 1, the pawl 5 is formed from different components. The pawl 5 has a first metallic core 16, wherein the extension 15 is formed from a plastic. The extension 15 rests with an engagement surface 17 on a protrusion 18 on the cam disc 9.Thus, the pawl 5 is guided in two ways: firstly by its engagement with the rotary latch and secondly by the interaction of the protrusion 18 on the cam disc 9 in interaction with the protrusion 18. Overall, the pawl 5 is pivotally mounted in the motor vehicle lock 1 around the axis 19 and the rotary latch 4 around the axis 20. Figure 2 shows the state of the locking mechanism 2 in which the motor vehicle lock 1 is when an electrical opening has been initiated by the operator. The electric drive 8 has moved the cam disc 9 clockwise in the direction of arrow P, resulting in interaction between the engagement surface 17 and the protrusion 18. The pawl 5 was moved out of the engagement area of ​​the main catch 7 by means of the extension 15, so that the pawl 5 is released from the main catch 7 on the rotary latch 4.The rotary latch 4 is now able to pivot around the axis 20 in the direction of arrow P1. The rotary latch 4 is pivoted by the forces acting on the rotary latch 4 from a rotary latch spring (not shown) and by the door seal pressure acting on the lock 1. P22057WO 15 November 15, 2023 When the locking pawl 5 is lifted via the cam disc 9, the closing pawl 11 is moved simultaneously, whereby the closing pawl 11 is pivoted around the axis 21. It should be noted that in this case, the drive lever 10 forms a fixed bearing point for the closing pawl 11. In other words, the drive lever 10 remains in its initial position, which is shown in Figure 1. In Figure 2, the locking pawl is pivoted in the direction of arrow P2 and the closing pawl 11 is pivoted around the axis 21.The drive lever 10 is accommodated, for example, in a lock case of the motor vehicle lock 1 so as to be pivotable about an axis 22 in the tailgate lock 1. Figure 2 shows the unlocked locking mechanism 2. Figure 3 shows the closing and opening drive 3 in a position corresponding to Figure 2. That is, the position of the pawl 5 in an unlocked position, as well as the closing and opening drive 3 in a position after electrical opening. The lock holder 6 is now released by the locking mechanism 2 so that the tailgate 1 can be opened. The advantage of this solution is that the electrical unlocking of the locking mechanism 2 can be achieved with a movement of the cam disk 9, and at the same time, a snow load function is realized via the interaction of the engagement surface 17 with the elevation 18.Snow load function here means that the pawl 5 is kept out of engagement with the rotary latch 4 during the complete opening movement of the rotary latch 4 in the direction of arrow P1. The interaction of the engagement surface 17 and the elevation 18 prevents the pawl 5 from engaging a notch of the rotary latch 4, i.e., a preliminary notch 23 as well as a main notch 7. Consequently, if the tailgate does not open due to a load, such as a thick layer of snow, the pawl 5 is kept out of engagement with the rotary latch until a control signal, for example, a microswitch 24 arranged on the rotary latch, is actuated, so that a clear signal is generated by the rotary latch 4 that the rotary latch 4 is in a fully open position. This ensures maximum security when opening the tailgate or opening the tailgate lock 1.Figure 4 shows the open tailgate, i.e., the tailgate lock 1 is spaced apart from the lock holder 6. A relative movement between the tailgate lock 1 and the usually stationary lock holder 6 allows the lock holder to move into the inlet area 25 of the rotary latch 4. To minimize noise during the interaction between the lock holder 6 and the rotary latch 4, the rotary latch has a plastic casing 26, which forms a buffer pocket 27 in the inlet area 25 to minimize noise. In Figure 4, the cam disc 4 has been electrically moved back clockwise in the direction of arrow P3, so that the cam disc returns to its initial position, as shown in Figure 1.By turning back the cam disc 9, the engagement between the engagement surface 17 and the elevation 18 is lost, so that the locking pawl 5, spring-loaded, comes into contact with the surface contour 14 of the rotary latch 4. The locking pawl 4 is thus spring-loaded in Figure 4 against the rotary latch 4, allowing the locking mechanism 2 to close again. Even when the cam disc 5 is moved back, the drive lever 10 remains in its position shown in Figure 1, so that only the closing pawl or the locking pawl are moved during electrical opening. The closing pawl 11 is also moved out of the engagement area with the rotary latch 4, allowing unhindered opening of the locking mechanism 2.In Figure 4, the closing pawl 11 also rests against the surface contour 14 of the rotary latch, spring-loaded, which on the one hand enables the locking pawl 5 to engage the pre-lock 23 as well as the main lock 7, and at the same time the closing pawl 11 is able, for example, to access the pre-lock 23 and enable the locking mechanism 2 to close. When closing, the rotary latch 4 is transferred from the pre-lock position to the main lock position, with the cam disc 9 being moved in the direction of arrow P3 for closing. When opening the tailgate lock 1 according to the invention, the advantage arises that, by means of a cam disc and the interaction between the locking pawl 5 and the closing and opening drive 3, on the one hand, electrical opening and, on the other hand, a snow load function can be realized. This implementation is made possible with minimal design resources and is therefore cost-effective.

[0002] P22057WO 18 15 November 2023 List of reference symbols 1 Tailgate lock 2 Locking mechanism 3 Closing opening drive 4 Rotary latch 5 Pawl 6 Lock holder 7 Main catch 8 Electric motor 9 Cam disc 10 Drive lever 11 Closing pawl 12 Control cam 13 Engagement sleeve 14 Surface contour 15 Extension 16 Metallic core 17 Engagement surface 18 Elevation 19, 20, 21, 22 Axle 23 Pre-lock 24 Microswitch 25 Inlet area 26 Plastic sheath 27 Buffer pocket P, P1, P2, P3 Arrow

Claims

P22057WO 19 November 15, 2023 Patent claims 1. Lock (1), in particular tailgate lock (1), for a motor vehicle having a locking mechanism (2) with a rotary latch (4) and at least one pawl (5), wherein the rotary latch (4) can be locked in a pre-locking position and a main locking position by means of the pawl (5), a closing and opening drive (3), wherein the locking mechanism (2) can be transferred from a pre-locking position to a main locking position by means of the closing and opening drive (3), and wherein the transfer takes place by means of a variable torque, characterized in that the pawl (5) can be held in a release position after the locking mechanism (2) has been unlocked by means of the closing and opening drive (3).

2. Lock (1) according to claim 1, characterized in that the closing and opening drive has a cam disc (9) and that a control cam (12) is arranged on the cam disc (9). 3.Lock (1) according to claim 2, characterized in that the cam disc (9) cooperates with a drive lever (10), and that closing can be carried out by means of the drive lever (10).

4. Lock (1) according to one of claims 1 to 3, characterized in that the locking pawl (5) can be held in the release position by means of the closing and opening drive (3) until an open position of the rotary latch is reached. P22057WO 20 November 15, 2023 5. Lock (1) according to claim 4, characterized in that the release position can be detected by means of a microswitch (24).

6. Lock (1) according to one of claims 3 to 5, characterized in that the drive lever (10) can be guided in the control cam (12).

7. Lock (1) according to one of claims 3 to 6, characterized in that the pawl (5) has an extension (50), and the extension (50) can be brought into engagement with the cam disc (9).

8. Lock (1) according to claim 7, characterized in that an elevation (18) is arranged on the cam disc (9), which elevation can be brought into engagement with an engagement surface (17) of the pawl (5).

9. Lock (1) according to one of claims 3 to 8, characterized in that the pawl (5) can be held in the release position by means of the cam disc (9) until the rotary latch (4) has reached an open position. 10.Lock (1) according to one of claims 1 to 9, characterized in that the pawl (5) is formed in two parts and has a metallic core (16) and an extension (15) formed from a plastic.

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