Drive unit for a locking element of a motor vehicle

Abstract

Drive unit (1) for a locking element (2) of a motor vehicle (3) with mechanical drive connections (4, 5) that are adjustable relative to each other, wherein the drive unit (1) comprises a retractable drive train coupled to the drive connections (4, 5) with an electric motor (6) and a feed gear (8), in particular a spindle-spindle nut gear, which is connected downstream of the electric motor (6) and has a geometric feed gear axis (7), wherein the drive unit (1) comprises a switching arrangement (12) by means of which the electric motor (6) can be controlled, wherein the switching arrangement (12) can be brought into a braking state in which the electric motor (6) operates as a generator and opposes a generator braking force to a force introduced into the drive connections (4, 5) via the locking element (2), and wherein the switching arrangement (12) can be brought into a release state.in which the electric motor (6) opposes a force introduced into the drive terminals (4, 5) with a lower, in particular no, generator braking force, characterized in that the circuit arrangement (12) has a mechanical switch (13), that the mechanical switch (13) has a neutral state in which the circuit arrangement (12) can assume the braking state, that the mechanical switch (13) can be actuated by a force introduced into the drive terminals (4, 5), and that actuation of the mechanical switch (13) by the force introduced into the drive terminals (4, 5) transitions the circuit arrangement (12) from the braking state to the release state.

Description

[0001] The present invention relates to a drive unit for a locking element of a motor vehicle according to the preamble of claim 1, a method for braking a locking element according to claim 13 and a locking element arrangement with a locking element according to claim 14.

[0002] The drive unit in question is used to adjust a locking element of a motor vehicle. Such a drive unit can, for example, be part of a drive mechanism for a tailgate, lid, hood, side door, sliding door, or the like of a motor vehicle. In this context, the term "locking element" is to be interpreted broadly.

[0003] Several methods exist for holding locking elements in the open position or an intermediate position to prevent them from closing unintentionally due to their own weight, wind, or other external influences. A permanent friction brake is often used for this purpose. The problem with this method is that the friction brake also engages when the locking element is moved by a motor, necessitating a larger electric motor. Mechanically actuated brakes are also known, but these are complex and prone to failure. Another known method is using the electric motor as a regenerative brake, typically a short-circuit brake, by connecting the motor's supply terminals, specifically by short-circuiting them. Regenerative braking of the electric motor offers several advantages, most notably its low wear.However, regenerative braking prevents not only unintentional but also intentional manual actuation of the locking element. Such devices are known in the prior art from DE 41 00 335 A1, DE 10 2008 042 183 A1 and DE 10 2008 057 014 A1.

[0004] It is a challenge to allow manual operation of the locking element in a simple way in a drive unit that is braked by operating the electric motor as a generator.

[0005] The invention is based on the problem of designing and further developing the known drive units in such a way that further optimization is achieved with regard to the aforementioned challenge.

[0006] The above problem is solved by the features of the characterizing part of claim 1.

[0007] The invention relates to a drive unit for a locking element of a motor vehicle with mechanical drive connections that are adjustable relative to each other, wherein the drive unit comprises a retractable drive train coupled to the drive connections, comprising an electric motor and a feed gear, in particular a spindle-spindle nut gear, connected downstream of the electric motor and having a geometric feed gear axis, wherein the drive unit comprises a circuit arrangement by which the electric motor can be controlled, wherein the circuit arrangement can be brought into a braking state in which the electric motor operates as a generator and opposes a force introduced into the drive connections via the locking element with a generator braking force, and wherein the circuit arrangement can be brought into a release state in which the electric motor exerts a lower force on a force introduced into the drive connections.in particular none, counteracting generator braking force.

[0008] The essential consideration is that a mechanical switch can be used which is actuated by introducing a force into the locking element, particularly resulting from manual operation, and which, through its actuation, changes the wiring of the electric motor in such a way that the braking effect of the electric motor is reduced, in particular eliminated.

[0009] Specifically, it is proposed that the circuit arrangement includes a mechanical switch, that the mechanical switch has a zero state in which the circuit arrangement can assume the braking state, that the mechanical switch can be actuated by a force introduced into the drive terminals, and that actuation of the mechanical switch by the force introduced into the drive terminals transfers the circuit arrangement from the braking state to the release state.

[0010] Claim 2 specifies preferred embodiments of the invention. According to claim 3, the mechanical switch can be arranged in a supply line of the electric motor and disconnects this line when actuated. In particular, this makes it possible in a simple manner to enable manual actuation of the locking element both in the braking state and during motorized adjustment of the locking element. In the latter case, the motorized actuation is automatically interrupted.

[0011] In a preferred embodiment according to claim 4, the mechanical switch directly disconnects a current path of a braking current of the electric motor. Thus, no control unit is required to evaluate a signal from the mechanical switch.

[0012] According to claim 5, the mechanical switch is only actuated after a threshold value of the applied force has been exceeded. Of particular interest is a variant in which the threshold value is the same for actuating the locking element in both its opening and closing directions, after subtracting the weight force of the locking element, so that the user has to apply approximately the same force in both directions to enable adjustment. Another variant is one in which the threshold value is direction-dependent, in order to offer, for example, greater protection against the accidental slamming of a locking element such as a tailgate, even if, for example, snow is present on the tailgate.

[0013] Claims 6 and 7 relate to a spring arrangement that opposes actuation of the mechanical switch. This allows the threshold value to be adjusted. In particular, according to claim 7, the mechanical switch can be biased into the zero position.

[0014] Claims 8 and 9 relate to the direction of the applied force and the preload in preferred embodiments.

[0015] Claim 10 relates to a control arrangement of the drive unit, which is preferably independent of the mechanical switch.

[0016] Claims 11 and 12 relate to the preferred placement of the mechanical switch and its efficient integration into the drive unit. The force applied to the drive terminals is preferably transmitted directly to the mechanical switch, which in turn preferably directly switches off the braking effect. This ensures a fast and efficient response to the applied force.

[0017] According to a further teaching as per claim 13, which has independent significance, a method for braking a locking element by means of a drive unit according to one of the preceding claims is claimed.

[0018] Reference may be made to all statements concerning the proposed drive unit.

[0019] According to a further teaching according to claim 14, which also has independent significance, a locking element arrangement is claimed with a locking element to which a drive unit according to one of the preceding claims is assigned.

[0020] Reference may be made to all statements concerning the proposed drive unit and the proposed procedure.

[0021] The invention will now be explained in more detail with reference to a drawing that illustrates only one embodiment. The drawing shows Fig. 1 the rear area of ​​a motor vehicle with a proposed drive unit for the locking element located there, Fig. 2. From a) to b) or to c), the release of the brake state by manual actuation of the locking element, Fig. 3. From a) to b) or to c), in each case the manual interruption of a motorized adjustment of the locking element and Fig. 4 schematically shows the connection of the electric motor to the control arrangement.

[0022] The proposed drive unit 1 is assigned to a locking element assembly, for example a tailgate assembly, which in turn is equipped with a locking element 2, here a tailgate. The locking element assembly is assigned to a motor vehicle 3 ( Fig. 1).

[0023] As mentioned at the outset, the locking element 2 can also be another locking element 2 of a motor vehicle 3, in particular a sliding door or a side door. All descriptions apply accordingly to other locking elements 2.

[0024] The drive unit 1 has a first, here lower, drive connection 4, which is coupled to the vehicle 3, and a second, here upper, drive connection 5, which is coupled to the locking element 2, here and preferably the tailgate. The drive connections 4, 5 are linearly adjustable relative to each other, thereby changing the distance between the drive connections 4, 5. By adjusting the drive connections 4, 5, the locking element 2 can be adjusted relative to the vehicle 3. At least one of the drive connections 4, 5, and in particular both drive connections 4, 5, is or are here and preferably designed as a ball socket or ball sockets.

[0025] The drive unit 1 has a regenerative drive train coupled to the drive connections 4, 5, comprising an electric motor 6 and a feed gearbox 8 connected downstream of the electric motor 6, the feed gearbox having a geometric feed axis 7. The feed gearbox 8 is designed according to Fig. 1 in particular a spindle-spindle nut drive with a spindle 9 and a spindle nut 10 in meshing engagement with it.

[0026] The “geometric feed gear axis” is the geometric axis along which, during operation, the feed gear components, in the case of a spindle-spindle nut drive, the spindle 9 and the meshing spindle nut 10, move linearly relative to each other as intended.

[0027] The feed mechanism 8 is designed to generate linear drive movements along the geometric feed mechanism axis 7 between a retracted position of the drive unit 1, in which the locking element 2 is preferably closed, and an extended position of the drive unit 1, in which the locking element 2 is preferably open. The spindle 9 is coupled to one of the drive connections 4, 5 via the electric motor 6, and the spindle nut 10 is coupled to the other. The spindle-spindle nut drive thus effects the linear adjustment of the drive connections 4, 5.

[0028] An intermediate gearbox, for example a reduction gearbox, can be placed between the electric motor 6 and the feed gearbox 8.

[0029] Here, and preferably, the drive unit 1 is pre-tensioned into its extended position by means of a drive spring arrangement 11, here a compression spring arrangement.

[0030] The drive unit 1 further comprises a circuit arrangement 12 by which the electric motor 6 can be controlled. In particular, the circuit arrangement 12 serves to apply an operating voltage to the electric motor 6.

[0031] The circuit arrangement 12 can be brought into a braking state in which the electric motor 6 operates as a generator and opposes a force introduced into the drive terminals 4, 5 via the locking element 2 with a generator braking force. Using an electric motor 6 for regenerative braking is a known method for employing an electric motor 6 as a brake. The generator braking force is generated by applying an induced motor voltage to a circuit, thus creating a motor current that opposes the movement of the electric motor 6.

[0032] Furthermore, the circuit arrangement 12 can be brought into an enabling state in which the electric motor 6 opposes a reduced, and in particular no, generator braking force to a force introduced into the drive terminals 4, 5. The enabling state and the braking state are different from each other. Here, and preferably, the enabling state serves for manual actuation by a user, who, for example, pulls on the locking element 2. Additionally, it is conceivable, but not shown here, that the enabling state serves for motorized adjustment by the drive motor.

[0033] It is essential that the circuit arrangement 12 includes a mechanical switch 13. Fig. 2 and Fig. Figure 3 shows an example of a mechanical switch 13. Here, and preferably, the mechanical switch 13 is a three-pole switch. Alternatively, two two-pole mechanical switches 13 could also be provided.

[0034] The mechanical switch 13 has a zero state ( Fig. 2a), Fig. 3a)), in which the circuit arrangement 12 can assume the braking state. Specifically, the circuit arrangement 12 only assumes the braking state in Fig. 2a) the braking state, in Fig. 3a) The electric motor 6 actuates the locking element 2. Accordingly, it is preferably provided here that in the zero state the electric motor 6 can adjust the locking element 2.

[0035] The mechanical switch 13 can be actuated by a force introduced into the drive terminals 4 and 5. Fig. 2b), Fig. Figures 2c), 3b), and 3c) show actuated states of the mechanical switch 13, of which exactly two are possible here, and preferably. Actuation of the mechanical switch 13 by the force introduced into the drive terminals 4, 5 transitions the circuit arrangement 12 from the braking state to the enabling state. Here, and preferably, the circuit arrangement 12 transitions to the enabling state in both actuated states of the mechanical switch 13. Here, and preferably, the circuit arrangement 12 transitions to the enabling state by actuation of the mechanical switch 13, regardless of whether the circuit arrangement 12 was previously in the braking state.

[0036] To understand the switching states, a look at Fig. 4. A microprocessor 16, a PWM controller 17, and a PWM output stage 18 are connected to a voltage source, here exemplified by a vehicle battery 14, as part of a control arrangement 15 which will be explained later. These control the electric motor 6 in a known manner. Below in Fig. The mechanical switch 13 is arranged in a housing 19 of the drive unit 1. It is evident that this switch disconnects one of the, here by way of example, two, supply lines of the electric motor 6 when the mechanical switch 13 is actuated.

[0037] The mechanical switch 13 is actuated mechanically by the force introduced into the locking element 2. It is important that the applied force actually causes the actuation and that the force is not first measured and analyzed by a sensor, with the actuation of the switch then occurring electrically.

[0038] Here, and preferably, the braking state is a short-circuit state in which the supply terminals of the electric motor 6 are short-circuited. This state is in Fig. 4 in the position of the circuit arrangement 12 shown in solid line.

[0039] The enabled state here is, and preferably is, an idle state in which the supply terminals of the electric motor 6 are not connected to each other. Fig. Figure 4 also shows that opening the mechanical switch 13 causes one of the supply terminals of the electric motor 6 to be at a floating potential. Thus, the electric motor 6 is automatically in the no-load state. Alternatively, a resistor can also be switched on using the mechanical switch 13, which only reduces the braking effect.

[0040] Accordingly, it is provided here, and preferably, that the mechanical switch 13 is arranged in a supply line of the electric motor 6 and that the actuation of the mechanical switch 13 disconnects a supply line of the electric motor 6.

[0041] It also follows, and preferably, that the mechanical switch 13 can be actuated by manually operating the locking element 2, while the electric motor 6 adjusts the locking element 2 motorically, and that the motorized adjustment of the locking element 2 is thereby interrupted, in particular directly by the mechanical switch 13. Fig. 2 the actuation of the mechanical switch 13 from the braking state shows, shows Fig. 3. The actuation of the mechanical switch 13 during the motorized adjustment, which is thereby interrupted. In the Fig. 2b) and Fig. 3b) is indicated by the hand next to the weight force 20, an actuation of the locking element 2 in the direction of gravity is indicated, while in the Fig. 2c) and 3) indicate an action against the direction of gravity.

[0042] It is also preferably provided that the mechanical switch 13 is arranged in a current path of a generator current, in particular short-circuit current, generated by the electric motor 6 in the braking state and that the actuation of the mechanical switch 13 by the force introduced into the drive terminals 4, 5 immediately interrupts the current path.

[0043] Here, and preferably, the mechanical switch 13 is actuated by the force introduced into the drive terminals 4, 5 when the applied force exceeds a predefined threshold. Thus, not every action on the locking element 2 immediately leads to the actuation of the mechanical switch 13. The threshold is implemented mechanically here, and preferably. Naturally, the threshold is therefore subject to tolerances and can fluctuate somewhat depending on various factors such as temperature. Preferably, the threshold, after subtracting a weight force 20 of the locking element 2, is either independent of or dependent on the direction of the force. For example, in the case of a tailgate, it may be advantageous to set the threshold higher when the tailgate is actuated in the direction of gravity than when actuated against it. In contrast, a direction-independent threshold may be advantageous for a sliding door.Here, and preferably, pinch protection is also implemented via the mechanical switch 13. The threshold value can be a threshold value of the acceleration or the magnitude of the force.

[0044] The Fig. 2 and Fig. Figure 3 shows that the drive unit 1 preferably has a spring arrangement 21. In particular, the threshold value can be implemented by means of the spring arrangement 21. The spring arrangement 21 counteracts actuation of the mechanical switch 13, in particular by a weight force 20 of the locking element 2. In the Fig. 2 and Fig. Figure 3 shows a spring 22 of the spring assembly 21, which counteracts any movement of the mechanical switch 13 in the direction of gravity. Here, and preferably, the spring assembly 21 prevents the mechanical switch 13 from being actuated by a weight force 20 of the locking element 2 in at least 90%, preferably 100%, of all positions of the locking element 2. The spring 22 is here, and preferably, dimensioned such that even a snow load on the tailgate does not cause the mechanical switch 13 to be actuated. Preferably, the spring assembly 21 compensates for the weight force 20 of the locking element 2 in at least one position of the locking element 2, so that the mechanical switch 13 is essentially load-free. Fig. 2a) and Fig. 3a) each show a force equilibrium between the weight force 20 of the locking element 2, insofar as it is not already compensated otherwise, and a spring force of the spring 22.

[0045] Here, and preferably, the spring assembly 21 biases the mechanical switch 13 into the zero position. The spring assembly 21 can comprise a disc spring, in particular a disc spring assembly. Here, the spring 22 is shown only schematically. The disc spring assembly can be attached to the Fig. 2 and Fig. The spring assembly 21 is installed in the position shown in Figure 3. Preferably, the disc spring pre-tensions the mechanical switch 13. Additionally or alternatively, the spring assembly 21 can include an elastomer 23 that pre-tensions the mechanical switch 13. It can be provided that the spring assembly 21 opposes actuation of the mechanical switch 13 in two, here both, directions.

[0046] Furthermore, and preferably, it is provided that the force introduced into the locking element 2, which actuates the mechanical switch 13, can be a force introduced in the opening direction of the locking element 2 and / or a force introduced in the closing direction of the locking element 2. The force can be introduced in both directions. Preferably, the mechanical switch 13, as shown, can be actuated in different directions depending on the direction of the introduced force. Here, and preferably, the mechanical switch 13 brings the circuit arrangement 12 into the enable state.

[0047] Additionally, and preferably, it is provided here that the mechanical switch 13 can be actuated against one direction of the preload of the mechanical switch 13 by the spring arrangement 21 and / or in the direction of the preload of the mechanical switch 13 by the spring arrangement 21 by the force introduced into the locking element 2. Here, the sum of the spring forces is meant.

[0048] Again, primarily focusing on Fig. 4. The drive unit 1 may be provided with a control arrangement 15. The control arrangement 15 actuates at least one switch 24 of the circuit arrangement 12, separate from the mechanical switch 13, in order to bring the circuit arrangement 12 into the braking state and preferably the release state and / or a motorized adjustment state when the mechanical switch 13 is in the zero state. It is therefore possible, and preferably possible, to bring the electric motor 6 into the release state independently of the mechanical switch 13. However, this possibility can also be omitted. In addition, the drive unit 1 can, of course, adjust the locking element 2 motorically, for which the motorized adjustment state is provided. Starting from Fig. 3a) The PWM control 17 is used to control the PWM output stage 18 so that the electric motor 6 drives the feed gearbox 8.

[0049] Here, and preferably, the control arrangement 15 does not switch the mechanical switch 13; in particular, the mechanical switch 13 is independent of the control arrangement 15. Here, and preferably, the control arrangement 15 detects a position of the mechanical switch 13 and, in response to an actuation of the mechanical switch 13, implements a control-related measure, for example, the output of a warning signal.

[0050] Furthermore, it is preferably provided here that the drive unit 1 has a housing 19, in particular a telescopic one, in which the electric motor 6, the feed gear 8 and the mechanical switch 13 are arranged ( Fig. 1) Preferably, the mechanical switch 13 is arranged between one of the drive terminals 4, 5 and the electric motor 6.

[0051] A look at the Fig. 2 and Fig. Figure 3 shows that here, and preferably, one contact of the mechanical switch 13, for example, the inner contact 25, is fixedly connected to one of the drive terminals 4, 5, here the upper drive terminal 5. Another contact, here the outer contact 26, of the mechanical switch 13 is here, and preferably, fixedly connected to the housing 19 of the drive unit 1. The contacts can be displaced relative to each other, here, and preferably, in two directions. When the contacts are in contact with each other, the mechanical switch 13 is closed, i.e., in the neutral position; otherwise, it is open, i.e., actuated. Of course, actuation could also result in the mechanical switch 13 being closed if the wiring is adjusted accordingly. Here, and preferably, the spring assembly 21 acts on one of the contacts, here the inner contact 25.

[0052] The force introduced into the drive terminals 4, 5 causes a displacement of one of the drive terminals 4, 5, here the upper drive terminal 5. This displacement is preferably relative to the housing 19 of the drive unit 1 and / or relative to the electric motor 6 and / or along the geometric feed axis 7. In particular, the displacement of the drive terminal 4, 5 occurs without a change in the length of the feed gear 8. This displacement actuates the mechanical switch 13. Here, and preferably, one of the contacts of the mechanical switch 13, here the inner contact 25, is displaced relative to the other contact along with the drive terminal 4, 5. Preferably, the spring arrangement 21 counteracts this displacement.

[0053] The relocated drive connection 4, 5 is preferably the drive connection 4, 5 attached to the locking element 2. The relocation can be in two directions, as shown by the transition of the Fig. 2a) and Fig. 3a) on the Fig. 2b) and Fig. 3b) or 2c) and 3c) shows.

[0054] Here, and preferably, the control arrangement 15 and, preferably, a part of the circuit arrangement 12 are arranged outside the housing 19.

[0055] According to a further teaching, a method for braking a locking element 2 by means of a proposed drive unit 1 is proposed.

[0056] Reference may be made to all statements concerning the proposed drive unit 1.

[0057] According to a further teaching, a locking element arrangement is proposed with a locking element 2 to which a proposed drive unit 1 is assigned.

[0058] Reference may be made to all statements concerning the proposed drive unit 1 and the proposed procedure.

Claims

[1] Drive unit (1) for a locking element (2) of a motor vehicle (3) with mechanical drive connections (4, 5) which are adjustable relative to each other, wherein the drive unit (1) comprises a rebounding drive train coupled to the drive connections (4, 5) with an electric motor (6) and a feed gear (8), in particular a spindle-spindle nut gear, which is connected downstream of the electric motor (6) and has a geometric feed gear axis (7), wherein the drive unit (1) comprises a switching arrangement (12) by means of which the electric motor (6) can be controlled, wherein the switching arrangement (12) can be brought into a braking state in which the electric motor (6) operates as a generator and opposes a generator braking force to a force introduced into the drive connections (4, 5) via the locking element (2), and wherein the switching arrangement (12) can be brought into a release state,in which the electric motor (6) opposes a lesser, in particular no, generator braking force to a force introduced into the drive connections (4, 5), , characterized by , that the circuit arrangement (12) has a mechanical switch (13), that the mechanical switch (13) has a zero state in which the circuit arrangement (12) can assume the braking state, that the mechanical switch (13) can be actuated by a force introduced into the drive terminals (4, 5), and that actuation of the mechanical switch (13) by the force introduced into the drive terminals (4, 5) brings the circuit arrangement (12) from the braking state to the release state. [2] Drive unit (1) according to claim 1, characterized by, that the braking state is a short-circuit state in which the supply terminals of the electric motor (6) are short-circuited, and / or that the release state is an idle state in which the supply terminals of the electric motor (6) are not connected to each other. [3] Drive unit (1) according to claim 1 or 2, characterized by , that the mechanical switch (13) is arranged in a supply line of the electric motor (6) and that the actuation of the mechanical switch (13) disconnects the supply line of the electric motor (6), and / or, that the mechanical switch (13) can be actuated by a manual actuation of the locking element (2) while the electric motor (6) is motorically adjusting the locking element (2), and that thereby the motorized adjustment of the locking element (2), in particular directly by the mechanical switch (13), is interrupted. [4] Drive unit (1) according to any one of the preceding claims, characterized by, that the mechanical switch (13) is arranged in a current path of a generator current, in particular short-circuit current, generated by the electric motor (6) in the braking state, and that the actuation of the mechanical switch (13) by the force introduced into the drive terminals (4, 5) immediately interrupts the current path. [5] Drive unit (1) according to any one of the preceding claims, characterized by , that the mechanical switch (13) is actuated by the force introduced into the drive terminals (4, 5) when the introduced force exceeds a predefined threshold value, preferably that the threshold value after subtracting a weight force (20) of the locking element (2) is independent or dependent on a force direction. [6] Drive unit (1) according to any one of the preceding claims, characterized by, that the drive unit (1) has a spring arrangement (21) that the spring arrangement (21) counteracts actuation of the mechanical switch (13), in particular by a weight force (20) of the locking element (2), in particular prevents actuation of the mechanical switch (13) by a weight force (20) of the locking element (2) in at least 90%, preferably 100%, of all positions of the locking element (2), preferably that the spring arrangement (21) compensates the weight force (20) of the locking element (2) in at least one position of the locking element (2), so that the mechanical switch (13) is essentially load-free. [7] Drive unit (1) according to any one of the preceding claims, characterized by, that the spring arrangement (21) biases the mechanical switch (13) into the zero position, and / or, that the spring arrangement (21) comprises at least one disc spring, in particular a disc spring assembly, preferably that the at least one disc spring biases the mechanical switch (13), and / or, that the spring arrangement (21) comprises an elastomer (23) that biases the mechanical switch (13). [8] Drive unit (1) according to any one of the preceding claims, characterized by , that the force actuating the mechanical switch (13) and introduced into the locking element (2) can be a force introduced in the opening direction of the locking element (2) and / or a force introduced in the closing direction of the locking element (2), preferably that the mechanical switch (13) can be actuated in different directions depending on the direction of the introduced force and preferably in each case brings the circuit arrangement (12) into the release state. [9] Drive unit (1) according to claims 6, optionally 7, and 8, characterized by , that the mechanical switch (13) can be actuated against a direction of the preload of the mechanical switch (13) by the spring arrangement (21) and / or in the direction of the preload of the mechanical switch (13) by the spring arrangement (21) by the force introduced into the locking element (2). [10] Drive unit (1) according to any one of the preceding claims, characterized by, that the drive unit (1) has a control arrangement (15), that the control arrangement (15) controls at least one switch (24) of the circuit arrangement (12) separate from the mechanical switch (13) in order to bring the circuit arrangement (12) into the braking state and preferably the release state and / or a motor adjustment state when the mechanical switch (13) is in the zero state, preferably that the control arrangement (15) does not switch the mechanical switch (13), further preferably that the mechanical switch (13) is independent of the control arrangement (15). [11] Drive unit (1) according to any one of the preceding claims, characterized by, that the drive unit (1) has a housing (19), in particular a telescopic one, in which the electric motor (6), the feed gear (8) and the mechanical switch (13) are arranged, preferably that the mechanical switch (13) is arranged between one of the drive terminals (4, 5) and the electric motor (6). [12] Drive unit (1) according to claim 11, characterized by , that the force introduced into the drive connections (4, 5) causes a displacement of one of the drive connections (4, 5) relative to the other of the drive connections (4, 5), in particular without a change in length of the feed gear (8), that the displacement causes the actuation of the mechanical switch (13), preferably that the spring arrangement (21) counteracts the displacement. [13] Method for braking a locking element (2) by means of a drive unit (1) according to one of the preceding claims. [14] Locking element arrangement with a locking element (2) to which a drive unit (1) according to one of the preceding claims is assigned.

Images