Actuating drive for a vehicle flap

Abstract

The invention relates to an actuating drive (1) for a vehicle flap (VF), comprising a housing (2) which can be telescopically extended along a drive axis (D); at least a first housing part (3) and a second housing part (4) which can be telescopically displaced relative to the first housing part (3); a first connection element (5), which is coupled to a first end (2a) of the housing (2), for connecting to one of the components consisting of the vehicle flap (VF) and the vehicle body (VB); a second connection element (6), which is coupled to the second end (2b) of the housing (2) opposite the first end (2a), for connecting to the other component of the components consisting of the vehicle flap (VF) and the vehicle body (VB); and a drive device (15) provided in the housing (2) for adjusting the second housing part (4) relative to the first housing part (3), wherein a coupling device (7) is provided between the first connection element (5) and the housing (2), and the coupling device (7) comprises a locking unit (9) having at least a first locking element (11) which locks the position of the coupling device (7) relative to the housing (2). According to the invention, an actuating drive which allows a flexible displacement of the vehicle flap, in particular in the event of an accident, is provided in that the first locking element (11) has a predetermined breaking point between a first sub-portion and a second sub-portion.

Description

[0001] Actuator for a vehicle hatch

[0002] The invention relates to an actuator for a vehicle flap, comprising a telescopic housing, a first connection element for connection to one of the vehicle flap and vehicle body, a second connection element for connection to the other of the vehicle flap and vehicle body, and a drive device arranged in the housing for motorized adjustment of the housing between a retracted and an extended position.

[0003] Linear actuators for vehicle doors or hatches are commonly used in practice. Under normal operating conditions, they automatically open and close a vehicle hatch or door between a closed and an open position. The maximum opening angle of the hatch is determined by the maximum stroke of the actuators, which are typically designed as linear drives. However, it is sometimes desirable to adjust a hatch beyond this predefined opening angle, for example, to perform servicing. Opening angles of approximately 60° are common, particularly for engine hoods, and are generally sufficient for routine maintenance. However, this maximum opening angle is not always adequate for more extensive servicing.Furthermore, it is sometimes necessary to allow additional freedom of movement for the vehicle flap in the event of an accident, for example to cushion an impact on the hood.

[0004] DE 102021 120210 A1 discloses an actuator for a vehicle hatch, comprising a telescopically extendable housing, wherein the housing includes a first housing part and a second housing part that is telescopically movable relative to the first housing part. The actuator further comprises a first connection element coupled to a first end of the housing for connection to one of the vehicle hatch and vehicle body, and a second connection element coupled to a second end of the housing opposite the first end for connection to the other of the vehicle hatch and vehicle body.

[0005] Finally, the actuator comprises a drive device arranged in the housing, designed as a spindle drive, for adjusting the second housing part relative to the first housing part, the drive device extending along a drive axis. Actuation of the drive device pivots the vehicle flap between a closed position and an open position by increasing the distance between the first and second connection elements.

[0006] DE 102023 114287 B3 discloses an actuator for a vehicle flap, comprising a housing, a first housing part, and a second housing part that is telescopically displaceable relative to the first housing part, wherein a first connecting element is coupled to a first end of the housing and a second connecting element is coupled to a second end of the housing. A coupling device is arranged between the first connecting element and the housing, which, together with the first connecting element, is displaceable relative to the housing along a drive axis of the actuator.

[0007] The object of the invention is to create an actuator for a vehicle flap which enables flexible relocation of the vehicle flap, especially in the event of an accident.

[0008] This problem is solved according to the invention by an actuator having the features of claim 1.

[0009] According to one aspect of the invention, an actuator, particularly for a vehicle hatch, is designed to comprise a housing telescopically extendable along a drive axis, wherein the housing includes at least a first housing part and a second housing part that is telescopically displaceable relative to the first housing part. The actuator further comprises a first connection element coupled to a first end of the housing for connection to one of the vehicle hatch and the vehicle body, and a second connection element coupled to a second end of the housing opposite the first end for connection to the other of the vehicle hatch and the vehicle body. Advantageously, the actuator can be articulated to connect between the vehicle hatch and the vehicle body.The actuator further comprises a drive device arranged in the housing for adjusting the second housing part relative to the first housing part, wherein the drive device extends along the drive axis, and wherein a coupling device is arranged between the first connecting element and the housing, the coupling device comprising a locking device with at least one first locking element which locks the position of the coupling device relative to the housing. Advantageously, this allows for subsequent lengthening or shortening of the actuator without having to increase the overall length of the drive device located in the housing or the stroke provided by the drive device. The actuator according to the invention is characterized in that the first locking element has a predetermined breaking point between a first subsection and a second subsection.

[0010] In an accident where a large force is applied to the vehicle hatch, the force is transferred to the predetermined breaking point between the first and second sections, causing it to break and releasing the coupling device or first connecting element relative to the housing. Advantageously, the distance between the first and second connecting elements is automatically increased or decreased by the coupling device's movement after the predetermined breaking point, while the actuator housing itself does not need to extend or retract further. Furthermore, the actuator is advantageously compact and yet allows for a larger adjustment range and evasive positions of the vehicle hatch in the event of an accident.

[0011] The predetermined breaking point is preferably designed to extend longitudinally transversely to the drive axis. It is advantageous that only the narrower side of the predetermined breaking point needs to break. This ensures that the required axial force is sufficiently low to allow the predetermined breaking point to break quickly and the coupling device or the first connecting element to be displaced rapidly. This is particularly important in the event of an accident, as a separate drive for raising the vehicle hatch into a pedestrian protection position may also be present, which then no longer has to work against the resistance of the drive device.

[0012] In a further advantageous embodiment of the actuator, the coupling device comprises a coupling housing that can be telescopically displaced relative to the housing. The coupling housing is particularly advantageously designed as a hollow cylinder and is arranged axially between the first connecting element and the housing at a first end. The coupling housing can advantageously be used to break off at a predetermined breaking point relative to the housing, thus releasing the displacement of the first connecting element. Preferably, the coupling housing extends radially around the first end of the housing. Advantageously, the displacement of the coupling housing is thus guided through the housing, resulting in an effective lengthening or shortening of the actuator, which allows for more flexible adjustment of the vehicle flap. The coupling housing is also advantageously accessible from the outside and easily replaceable.Furthermore, it is advantageous that the first connection element is permanently attached to one end of the coupling housing.

[0013] To allow the second section of the first locking element to shear off or break away, it is preferably provided that the second section of the first locking element radially penetrates the coupling housing in a locked position. Preferably, the first locking element thus provides a positive connection between the coupling housing and the actuator housing, which prevents axial displacement of the coupling housing along the drive axis. The first locking element is expediently displaceable between the locked position and a release position, whereby in the release position displacement of the coupling device relative to the housing is permitted.

[0014] Preferably, the second section projects partially beyond the outer surface of the coupling housing in the locked position. Advantageously, the second section of the first locking element passes through a first recess in the coupling housing in the locked position. Advantageously, under high axial loads between the first and second connecting elements, the second section is automatically detached from the first section by the fracture of the predetermined breaking point.

[0015] In a preferred embodiment, the first locking element has a slot-shaped recess between the first and second subsections, with the slot-shaped recess being located at the level of the predetermined breaking point. Advantageously, the first subsection can move relative to the second subsection in such a way that the predetermined breaking point can actually be broken. Preferably, the slot-shaped recess is semicircular, with the radius of the slot-shaped recess approximately corresponding to the mean radius of the hollow cylindrical coupling housing. Advantageously, the predetermined breaking point is located radially at the level of the inside of the coupling housing in the locked position. Corresponding to the shape of the slot-shaped recess, the predetermined breaking point is semicircular along its longitudinal extent.The mean radius of the predetermined breaking point along its longitudinal extent corresponds approximately to the inner radius of the coupling housing. Advantageously, the second section of the first locking element can be sheared or broken off by displacing the coupling housing relative to the housing.

[0016] In a preferred embodiment, the coupling device is movable at least between a first position intended for normal operation and a second position intended for service purposes. Normal operation in this context means that the actuator, as usual, performs a motorized adjustment of the vehicle hatch between the fully closed position and an open position intended for maintenance purposes. Service purposes are defined as those purposes where it is necessary to pivot the vehicle hatch beyond the opening angle typical during normal operation. For example, it may be provided that an opening angle of up to 60° is provided for the vehicle hatch during normal operation, whereas an opening angle of 90° or even more is required for service purposes.

[0017] The locking device preferably comprises a base housing in which the first locking element is arranged. Advantageously, the base housing has a bore in which the first locking element can be displaced between the locked and released positions. The bore advantageously serves as a guide for the first locking element. Particularly preferably, the bore is perpendicular to the drive axis of the drive device or to a longitudinal axis of the housing. More preferably, the base housing is rigidly connected to the first housing part. Advantageously, a positive locking of the coupling housing can be achieved by the radial overlap of the first locking element with the coupling housing and the first housing part.

[0018] The locking device preferably includes a preloading element that biases the first locking element into the locked position. Advantageously, unlocking or moving the first locking element into the release position can be achieved by applying an external force, whereas locking occurs automatically due to the preloading element. The first locking element expediently has a top surface that protrudes from the coupling housing in the locked position. Advantageously, the first locking element can be pressed from the outside inwards to unlock it.

[0019] In a preferred embodiment, the actuator is used in a pedestrian protection system as described above. This system comprises a fast-acting actuator or a pre-tensioning device that moves the vehicle's tailgate into a raised pedestrian protection position. Due to the predetermined breaking point, the actuator allows for rapid extension of its overall length. Furthermore, the pedestrian protection system can be resettable by moving the tailgate from the raised pedestrian protection position to a closed, default position. This repositioning can be performed either manually or automatically. This is particularly advantageous if the pedestrian protection system is triggered even though no accident or impact has occurred.

[0020] Further advantages, properties, features and further developments of the claimed invention will become apparent from the following description of a preferred embodiment and from the dependent claims.

[0021] The invention is explained in more detail below with reference to a preferred embodiment and the accompanying drawings.

[0022] Fig. 1 shows a preferred embodiment of an actuator 1 in a cross-sectional view,

[0023] Fig. 2 shows the locking device 9 in a

[0024] Cross-sectional view. Fig. 3 shows the first locking element 11 in a perspective view.

[0025] Fig. 4 shows the actuator 1 from Fig. 1 with the coupling housing 8 of the coupling device 7 partially displaced in the extension direction.

[0026] Fig. 5 shows the actuator 1 from Fig. 1 with the coupling housing 8 of the coupling device 7 partially displaced in the direction of entry.

[0027] Fig. 1 shows a preferred embodiment of an actuator 1 in a cross-sectional view. The actuator 1 comprises a housing 2 extending longitudinally along a drive axis D, which is telescopically extendable and retractable. The housing 2 comprises a first housing part 3 and a second housing part 4, wherein the second housing part 4 is arranged to be telescopically movable within the first housing part 3. A first connecting element 5 for connection to a vehicle body VB, shown here in dashed lines, is attached to a first end 2a of the housing 2. In the embodiment shown here, the first connecting element 5 is designed as a ball socket. Advantageously, this allows for an articulated coupling between the actuator 1 and the vehicle body VB.

[0028] At a second end 2b of the housing 2, a second connecting element 6 is attached for connection to a vehicle flap VF, shown here with dashed lines. The second connecting element 6 is also designed as a ball socket. Advantageously, the actuator 1 can be pivotally connected between the vehicle body VB and the vehicle flap VF via the first connecting element 5 and the second connecting element 6, whereby extending the actuator 1 or the telescopic housing 2 pivots the vehicle flap VF into an open position, or retracting the actuator 1 or the telescopic housing 2 pivots the vehicle flap VF into a closed position. A coupling device 7 is arranged axially between the first connecting element 5 and the housing 2, with the first connecting element 5 being rigidly connected to the coupling device 7.The coupling device 7 comprises a coupling housing 8, which is axially displaceable along the drive axis D between a first locking position shown here and free positions shown in Fig. 4 and Fig. 5, respectively, relative to the housing 2. The coupling housing 8 is designed as a hollow cylinder, which radially surrounds the first end 2a, specifically the first housing part 3. Accordingly, the coupling housing 8 is designed as a telescopically extendable extension of the housing 2 relative to the first housing part 3.

[0029] The coupling device 7 further comprises a locking device 9, which locks the axial position of the coupling device 7 or the coupling housing 8 relative to the housing 2 during normal operation. The locking device 9 comprises a base housing 10, in which a first locking element 11, designed as a locking bolt, is received. The locking device 9 further comprises a preloading element 12, which biases the first locking element 11 radially outwards into the locking position shown here. In the embodiment shown here, the preloading element 12 is designed as a helical compression spring.

[0030] The locking device 9 further comprises a second locking element 13, which is arranged opposite the first locking element 11. The preloading means 12 is arranged between the first locking element 11 and the second locking element 13, so that both locking elements 11 and 13 are simultaneously preloaded into the locking position by the preloading means 12. In this locking position, the first locking element 11 engages a first recess 8a provided in the coupling housing 8, and the second locking element 13 engages a second recess 8b in the coupling housing 8, radially opposite the first recess 8a. Since the base housing 10 is fixedly connected to the first housing part 3, a first axial position of the first connecting element 5 relative to the housing 2 is thus established.

[0031] To define a second axial position of the first connecting element 5 relative to the housing 2, the coupling housing 8 has a third recess 8c and a fourth recess 8d radially opposite the third recess 8c. The third recess 8c and the fourth recess 8d are arranged axially below the first recess 8a and second recess 8b. Advantageously, the maximum distance between the first connecting element 5 and the second connecting element 6 is increased in the second axial position of the first connecting element 5. Advantageously, the vehicle flap VF can be pivoted relative to the vehicle body VB by a larger opening angle, for example, by up to 90° instead of only 60°.

[0032] The actuator 1 further comprises a drive device 15 arranged in the housing 2, wherein the drive device 15 is designed as a spindle drive in the embodiment shown here. The drive device 15 comprises a motor 16 designed as an electric motor, a gearbox 18, a torque limiting device 19 and a brake device 20, which are arranged axially between the motor 16 and a spindle rod 21 driven by the motor 16.

[0033] The spindle rod 21 is rotatably mounted in the housing 2 via a ball bearing 22. A spindle nut 24, arranged in a guide tube 23 to prevent rotation, is threaded in engagement with the spindle rod 21, so that when the spindle rod 21 is rotated about the drive axis D, the guide tube 23 is axially displaced together with the spindle nut 24. The guide tube 23 is fixedly connected to the second connecting element 6 via a screw connection, the second connecting element 6 being in turn connected to the second housing part 4 via an interference fit. The actuator 1 further comprises a helical compression spring 25 arranged between the first housing part 3 and the second housing part 4, which assists the actuating movement of the vehicle flap VF.

[0034] Fig. 2 shows the locking device 9 in a cross-sectional view. The base housing 10 comprises a coupling section 10a, which is provided for coupling with the housing 2 or, in the present embodiment, with the first housing part 3 (see Fig. 1). The coupling section 10a is hollow cylindrical, with its outer diameter approximately corresponding to the inner diameter of the first housing part 3. Advantageously, the base housing 10 of the locking device 9 can be connected to the first housing part 3 by an interference fit, a screw connection, and / or other fastening methods, in particular bonding or welding. The base housing 10 is made of plastic and is manufactured by injection molding.

[0035] The basic housing 10 further comprises a locking section 10b, in which the first locking element 11, the preloading device 12, and the second locking element 13 are accommodated. For this purpose, a bore B is provided in the locking section 10b, which is tapered in the middle, the inner diameter of which corresponds to the outer diameter of the preloading device 12. At its opposite ends, the bore B has an inner diameter that corresponds to the outer diameter of the first locking element 11 and the second locking element 13, respectively.

[0036] The first locking element 11 has a first section 11a facing the preloading element 12 and a second section 11b, which is connected to the first section 11a via a predetermined breaking point 11c. The first section 11a has an annular stop surface 30 on its inside, which is bounded by an outer wall 31 and an inner wall 32 concentrically surrounded by the outer wall 31. The preloading element 12, designed as a helical compression spring, bears against the stop surface 30 at one end, with the outer wall 31 and the inner wall 32 simultaneously forming guide surfaces for the preloading element 12. This advantageously ensures that the preloading element 12 cannot slip relative to the first locking element 11. The second subsection 11b projects radially out of the locking section 10b of the base housing 10 and passes through the recess 8a of the coupling housing 8 shown in Fig. 1.

[0037] Due to the predetermined breaking point 8c between the first section 11a and the second section 11b, the second section 11b can shear off or break off under a strong external axial load on the actuator, particularly in an accident. The coupling housing 8 is then automatically decoupled from the housing 2, so that the first coupling element 5 can be freely displaced relative to the second coupling element 6, allowing the vehicle flap VF to either retract under the vehicle body VF or be lifted upwards.

[0038] Advantageously, the predetermined breaking point 11c is designed to extend longitudinally perpendicular to the drive axis D. Accordingly, a fracture occurs due to a load acting parallel to the significantly narrower side of the predetermined breaking point 11c, which occurs along the drive axis D in an accident involving force acting on the vehicle flap.

[0039] Fig. 3 shows the first locking element 11 in a perspective view. The first locking element 11 is made of plastic and is an injection-molded part. The first section 11a forms the lower end of the first locking element 11, and the second section 11b forms the upper end. Between the first section 11a and the second section 11b is the predetermined breaking point 11c, which connects the first section 11a and the second section 11b during normal operation of the actuator. At the level of the predetermined breaking point 11c, the locking element has a slot-shaped recess 11d, which is provided for forming the predetermined breaking point 11c. The slot-shaped recess 11d allows the second section 11b to break along a predetermined breaking edge running parallel to the longitudinal axis of the predetermined breaking point 11c.The slot-shaped recess 11d has a semicircular contour, and the predetermined breaking point 11c also has this semicircular contour. This is because the predetermined breaking point runs along the hollow cylindrical inner surface of the coupling housing.

[0040] Fig. 4 shows the actuator 1 from Fig. 1 with the coupling housing 8 of the coupling device 7 partially displaced in the extension direction. Due to a strong external force acting in the direction of the drive axis D, the second section 11b of the first locking element 11 was sheared or broken off from the first section 11a. Similarly, the second section 13b of the second locking element 13 was sheared or broken off from the first section 13a. Consequently, the first locking element 11 no longer passes through the first radial recess 8a of the coupling housing 8, and the second locking element 13 no longer passes through the second recess 8b of the coupling housing. As a result, the coupling housing 8 and the first connecting element 5 connected to the coupling housing 8 have been displaced into the extended position relative to the second connecting element 6.

[0041] Advantageously, releasing the coupling housing 8 or the first coupling element 5 relative to the housing 2 creates the possibility that the vehicle flap VF could be moved into a raised position in the state shown here, without the actuator 1 offering significant resistance to this movement. In this process, the base housing 10 was moved towards the third recess 8c and the fourth recess 8d, with the locking section 10b being arranged axially between the first recess 8a or second recess 8b and the third recess 8c or fourth recess 8d.

[0042] Fig. 5 shows the actuator 1 from Fig. 1 with the coupling housing 8 of the coupling device 7 partially displaced in the retraction direction. Due to a strong external force acting in the direction of the drive axis D, the second section 11b of the first locking element 11 was sheared or broken off from the first section 11a. Similarly, the second section 13b of the second locking element 13 was sheared or broken off from the first section 13a. Consequently, the first locking element 11 no longer passes through the first radial recess 8a of the coupling housing 8, and the second locking element 13 no longer passes through the second recess 8b of the coupling housing 8, so that the coupling housing 8 and the first connecting element 5 connected to the coupling housing 8 have been displaced into the retracted position relative to the second connecting element 6.The base housing 10 was displaced towards the first connecting element 5, with the locking section 10b being arranged axially between the first recess 8a or second recess 8b and the first connecting element 5. In the state shown here, the vehicle flap VF was moved into a position recessed relative to the vehicle body VB.

[0043] The invention has been explained above with reference to an exemplary embodiment in which two locking elements are arranged opposite each other in a base housing. Advantageously, this provides symmetrical locking relative to the drive axis; however, it is understood that only one locking element or more than two locking elements can also be provided.

[0044] The above explanation uses an exemplary embodiment in which the coupling housing is connected to the first connection element, which is coupled to the vehicle body. It is understood that the coupling housing can also be connected to the second connection element, which is coupled to the vehicle hatch.

Claims

PATENT CLAIMS 1. Actuator (1), in particular for a vehicle flap (VF), comprising a housing (2) telescopically extendable along a drive axis (D), comprising at least a first housing part (3) and a second housing part (4) telescopically displaceable relative to the first housing part (3), a first connection element (5) coupled to a first end (2a) of the housing (2) for connection to a vehicle flap (VF) and vehicle body (VB), a second connection element (6) coupled to a second end (2b) of the housing (2) opposite the first end (2a) for connection to the other of vehicle flap (VF) and vehicle body (VB), a drive device (15) arranged in the housing (2) for adjusting the second housing part (4) relative to the first housing part (3), wherein a coupling device (7) is arranged between the first connecting element (5) and the housing (2), wherein the coupling device (7) comprises a locking device (9) with at least one first locking element (11) which locks the position of the coupling device (7) relative to the housing (2), characterized by that the first locking element (11 ) has a predetermined breaking point (11 c) between a first subsection (11a) and a second subsection (11 b).

2. Actuator according to claim 1, characterized in that the predetermined breaking point (11c) extends longitudinally transversely to the drive axis (D).

3. Actuator (1) according to claim 1 or 2, characterized in that the coupling device (7) comprises a coupling housing (8) that is telescopically displaceable relative to the housing (2).

4. Actuator according to claim 3, characterized in that the coupling housing (8) runs radially around the first end (2a) of the housing (2).

5. Actuator according to claim 3 or 4, characterized in that the first connecting element (5) is firmly connected to one end of the coupling housing (8).

6. Actuator (1 ) according to one of claims 3 to 5, characterized in that the second subsection (11b) of the first locking element (11) radially penetrates the coupling housing (8) in a locking position.

7. Actuator according to claim 6, characterized in that the second subsection (11 b) in the locking position partially projects beyond the outside of the coupling housing (8).

8. Actuator according to one of claims 2 to 7, characterized in that the second subsection (11 b) of the first locking element (11) penetrates a first recess (8a) of the coupling housing (8) in the locking position.

9. Actuator according to one of the preceding claims, characterized in that the first locking element (8) has a slot-shaped recess (11d) between the first subsection (11a) and the second subsection (11b), wherein the slot-shaped recess (11d) is arranged at the level of the predetermined breaking point (11c).

10. Actuator according to claim 9, characterized in that the slot-shaped recess (11d) is semicircular, wherein the radius of the slot-shaped recess (11d) corresponds approximately to the mean radius of the coupling housing (8).

11. Actuator according to one of claims 3 to 10, characterized in that the predetermined breaking point (11c) is arranged radially at the level of the inside of the coupling housing (8) in the locking position.

12. Actuator according to one of the preceding claims, characterized in that the predetermined breaking point (11c) is formed in a semicircular shape along its longitudinal extent.

13. Actuator according to claim 12, characterized in that the mean radius of the predetermined breaking point along its longitudinal extent corresponds approximately to the inner radius of the coupling housing (8).

14. Actuator according to one of the preceding claims, characterized in that the locking device (9) comprises a base housing (10) in which the first locking element (11) is arranged.

15. Actuator according to claim 14, characterized in that the base housing (10) has a bore (B) in which the first locking element can be displaced between the locking position and the release position.

16. Actuator according to claim 15, characterized in that the bore (B) is perpendicular to the drive axis (D) of the drive device (15) or to a longitudinal axis of the housing (2).

17. Actuator (1) according to any one of claims 14 to 16, characterized in that the base housing (10) is fixedly connected to the first housing part (3).

18. Actuator (1 ) according to one of the preceding claims, characterized in that the locking device (9) comprises a preloading means (12) which preloads the first locking element (11 ) into the locking position.

19. Use of an actuator (1) according to one of the preceding claims in a pedestrian protection system, wherein the pedestrian protection system comprises a drive or a pretensioning means which moves the vehicle flap (VF) into a raised pedestrian protection system position.

20. Use according to claim 19, characterized in that the pedestrian protection system is designed to be resettable by moving the vehicle flap (VF) from the raised pedestrian protection position to a closed basic position.

Images