Motor vehicle sliding door drive

Abstract

The invention relates to a motor vehicle sliding door drive (1) comprising an electric drive which has a transmission connected downstream of the drive and a cable drum; a door element movably mounted on the motor vehicle; and a drive carriage (3) for the door element, wherein the drive carriage (3) at least one drive cable (4) is connected to the electric drive, the drive cable (4) is connected to the drive carriage (3) via ball head connections (16, 17), a ball head (21) of the ball head connections (16, 17) is held in a ball socket (14, 15) by means of a securing ring (22), and the ball head (21) can be held in the ball socket (14, 15) by means of at least one other spring element (20).

Description

[0001] INTERNAL

[0002] P24172WO November 14, 2025

[0003] Description

[0004] Motor vehicle sliding door drive

[0005] The invention relates to a motor vehicle sliding door drive comprising an electric drive with a gearbox downstream of the drive and a cable drum, a door element slidably arranged on the motor vehicle, a drive carriage for the door element, wherein the drive carriage is connected to the electric drive by means of at least one drive cable, in particular indirectly via a cable drum, and the drive cable is connected to the drive carriage via ball joint connections, wherein a ball head of the ball joint connection is held in a ball socket by means of a retaining ring.

[0006] In modern motor vehicles, sliding doors are usually mounted on roller guides and tracks along the vehicle. To increase comfort, these sliding doors are typically electrically operated, opening, and closing. For this purpose, electric drives are equipped with a downstream gearbox and, depending on the design of the sliding door drive, a cable drum that, via pulleys, allows the door element to move back and forth. Depending on the direction of travel, the drive cables pull the door element into an open or closed position. Such sliding door drives are known from the prior art.

[0007] A sliding door drive is known, for example, from EP 1 905 629 Al. In this case, an electric drive acts on a cable drum via a downstream gearbox.

[0008] P24172WO November 14, 2025, wherein the cable drum receives the drive cable and, depending on the direction of rotation of the cable drum, moves the slidably arranged door element back and forth. The ends of the cables are attached to a drive carriage, the guide carriage being guided in a rail and moving the door element. By means of the drive mode, a torque is thus transmitted to the gearbox, whereby the gearbox moves the cable drum and the drive cable, via its connection to the guide carriage, can move the door element into an open or closed position.

[0009] Flexible pull cables are frequently used to drive the door element, as these flexible cables have proven particularly suitable for deflecting and thus transmitting the drive force to the movable drive carriage in a targeted manner. DE 10 2012 012 018 A1 discloses a connection between a drive cable and a guide carriage. The connection of the drive cable to the drive carriage is achieved via an angle joint in the form of a ball joint. The publication discloses a connection between a ball joint and a ball socket and presents a solution for achieving a safe and quiet transmission of the drive force from the drive cable to the drive carriage. A ball socket is attached to the drive cable, into which a bolt with a ball joint is inserted, the bolt engaging directly or indirectly with the guide carriage.On the one hand, the ball joint connection allows movement in the pull cable to be compensated for, and on the other hand, it allows high forces to be transmitted to the drive carriage. INTERNAL.

[0010] P24172WO November 14, 2025

[0011] High forces in the drive mechanism of a sliding door occur, for example, when the door element moves into a closed position and is forced into this position against the force of a door seal. To ensure reliable transmission of the drive force to the guide carriage even in such extreme situations, the ball joint is held in the ball socket by means of a retaining ring. DE 10 2012 012 018 A1 therefore demonstrates a method for transmitting a drive force to a door element using a pull cable in combination with a ball joint connection.

[0012] Unfavorable force transmissions or forces acting on the ball joint connection, such as those that can occur when the drive carriage is deflected within a guide track, pose a risk that the retaining ring will not provide sufficient support for the ball joint connection. This is particularly relevant when the door element moves from a straight sliding motion along the vehicle to the closing position. In this situation, the guide carriage is moved within its guide track towards the door opening and undergoes a deflection. This deflection, combined with the increased force required when closing the door element, causes the drive cable to twist and alters the force acting between the ball joint and the socket.However, with electrically operated sliding doors, it must be ensured at all times and throughout the vehicle's lifetime that the door element closes securely. This is where the invention comes in. INTERNAL.

[0013] P24172WO November 14, 2025

[0014] The object of the invention is to improve the ball joint connection in a sliding door drive. Furthermore, the invention aims to provide additional safety even in extreme situations and under extreme forces at the ball joint connection. The invention also aims to provide a structurally simple and cost-effective solution for securing the ball joint connection in the sliding door drive.

[0015] Further developing the invention, it is also an objective to counteract the misuse of the ball joint connection and the potential damage to the door sliding drive that may result. For example, if the drive is moved without a fixed connection between the cables and the carriage, and thus the cables are slack, this can lead to the cables becoming entangled on the cable drum and ultimately to the failure of the drive unit.

[0016] The problem is solved by the features of independent claim 1. Advantageous embodiments are specified in the dependent claims. It should be noted that the exemplary embodiments described below are not limiting; any variation of the features described in the description and in the dependent claims is possible.

[0017] According to claim 1, the object of the invention is achieved by comprising a motor vehicle sliding door drive comprising an electric drive with a gearbox downstream of the drive and a cable drum, a door element slidably arranged on the motor vehicle, an INTERNAL

[0018] P24172WO November 14, 2025

[0019] Drive carriage for the door element, wherein the drive carriage is connected to the electric drive by means of at least one drive cable, in particular indirectly via the cable drum, and the drive cable is connected to the drive carriage via ball joint connections, wherein a ball joint of the ball joint connection is held in a ball socket by means of a retaining ring, wherein the ball joint is secured in the ball socket by at least one further retaining element. The inventive design of the motor vehicle sliding door drive now makes it possible to provide an additional retaining mechanism for the ball joint in the ball socket. Due to the double securing of the ball joint and the spring element used, an additional spring force can act as a preload on the ball joint connection and thus improve the retention of the ball joint in the ball socket.The spring element acts between the ball head and the socket, securing the ball head in the socket and introducing a preload into the ball head. This preload acts in the direction of the connection between the ball head and the socket. Any force exerted on the ball head connection by unfavorable forces can thus be absorbed by the additional spring element.

[0020] The vehicle sliding door drive is equipped with a drive unit consisting of an electric motor, a downstream gearbox, and a cable drum. Such sliding door drives are preferably installed in the vehicle body and act on a guide carriage arranged in a track. The guide carriage, in turn, engages with the door element, which is usually held in roller guides and thus movable. The cable drum is connected internally.

[0021] P24172WO November 14, 2025 preferably a pull rope is attached or wound onto the drum so that it can be wound and unwound when the drum rotates. Depending on the direction of rotation of the drum, one end of the pull rope is wound up and the other end is unwound. It should be noted, for the avoidance of doubt, that, by way of example, two pull ropes may also be present, which are then connected separately to the drum, so that, depending on the direction of rotation of the drum, one rope is wound up and the other is unwound.

[0022] Pulling the cable causes the drive carriage to move in the guide rail via the ball joint connection, and the connection of the drive carriage to the door element, which is movably arranged in the vehicle, results in... :The sliding door is moved. Besides being inserted into the closed position, the door element can be equipped with an electrically operated vehicle lock, so that after the vehicle lock reaches a pre-latch position, the door element is moved from the pre-latch position to the main latch position by a drive unit in or on the vehicle lock. In other words, the complete closing process of the door element can be carried out either by the sliding door drive or by the closing action of the vehicle lock.

[0023] As explained above, the door element can be in different positions. On the one hand, it can be guided linearly along one side of the vehicle until, for example, it reaches an end position where it is held and secured in the open position, for instance, by means of an auxiliary lock. INTERNAL

[0024] P24172WO November 14, 2025

[0025] When the door element closes, it travels along the side of the vehicle and is guided into the vehicle's door opening. The linear movement of the door element along the vehicle guides it into the vehicle, ensuring the door opening closes completely. This deflection of the door element can lead to unfavorable force distribution in the ball socket or ball joint. This can cause the ball socket to tilt relative to the ball. The additional spring element, providing extra security between the ball joint and ball socket, ensures greater safety and extends the lifespan of the sliding door drive.

[0026] It has been found that it can be advantageous if the additional spring element can be mounted externally via the ball socket. Attaching the spring element to the outside of the ball socket allows for simple and easy installation, even after the ball head has been connected to the socket. For example, the spring element can be held on the pull cable itself during installation and then guided over the ball socket after the ball head and socket have been connected. Retrofitting to existing systems is also possible, as the spring element is mounted externally via the ball socket. The ball socket is connected to the pull cable. The ball socket is positioned for mounting the ball head, and the ball head is inserted into the socket via the retaining ring and secured in place by the first retaining element, i.e., the retaining ring.By means of an INTERNAL.

[0027] P24172WO 14 November 2025 Following the subsequent installation of the spring element, a second locking element is therefore introduced into the ball joint connection.

[0028] A structurally simple solution has proven to be achieved when the spring element completely overlaps the ball socket. By positioning the spring element on the ball socket, easy assembly of the spring element is ensured, as the ball socket can serve as a guide for the spring element. Furthermore, the ball socket can provide support for the spring element in the assembled state, thus ensuring a secure hold of the spring element in the angle joint or ball-joint connection. Preferably, the spring element is designed such that a positive-locking engagement with the ball socket is possible, so that the ball socket serves as a guide during assembly.

[0029] If the spring element is designed as a spring steel strip, a further embodiment of the invention emerges. The use of a steel strip offers the advantage of a cost-effective material that also provides a permanently elastic, stable, and durable solution for securing the position of the ball head. Furthermore, a bent spring steel strip can also be supplied cost-effectively. Due to its flexibility, the spring steel strip is also easy to handle and install.

[0030] If the spring element is designed to lock into a ball-head neck, forming a locking contour, then INTERNAL

[0031] P24172WO November 14, 2025 presents a further embodiment of the invention. The ball head is inserted into the ball socket and initially secured in position by means of a spring ring within the ball socket. A ball head neck, which transitions into a bolt, is attached to the ball head. The bolt is then mounted, for example, in a mounting flange of the drive slide. When the spring element now passes over the ball socket, the spring element, and preferably the spring steel strip, is able to engage in the ball head neck protruding from the ball socket. For this purpose, the spring element has a detent contour that can engage into the ball head neck when the spring element is mounted beyond the ball socket. Thus, on the one hand, the spring steel strip facilitates easy guidance over the ball socket, and on the other hand, the detent contour ensures precise positioning of the spring element on the ball head connection.The ball-head neck offers an advantageous position for securing the spring element, since the ball-head neck protrudes from the ball socket and, due to its tapering compared to the ball head, provides a structurally favorable possibility for locking the spring element.

[0032] If the spring element has at least one insertion aid, preferably arranged on both sides, this results in a further advantageous embodiment of the invention. The spring element is preferably slid over the ball socket and moved into the mounting position. If the spring element has an insertion aid, the ball socket can provide guidance for the spring element, and the insertion aid facilitates its engagement on the ball head neck. Preferably, an insertion aid is provided internally on both sides at a slot or on the locking contour.

[0033] P24172WO 10 14 November 2025 is provided to facilitate easy mounting on the ball joint neck. Furthermore, it can be advantageous to have an insertion aid on both sides of the spring steel strip, resulting in a symmetrical design of the spring steel strip or spring element. This allows for mounting from either side and also provides a locking mechanism. Incorrect pre-assembly of the spring element can thus be prevented. The insertion aid can, for example, be in the form of an insertion ramp in the area of ​​the detent contour or the opening slot of the spring element.

[0034] If the spring element is essentially designed as a spring ring, with a chamfer in the area of ​​the detent contour, a further embodiment of the invention can be achieved. The spring element is preferably designed as a spring steel strip and forms a spring ring that extends circumferentially around the ball socket, which also has an essentially round shape. The largest possible contact surface of the spring ring on the ball socket serves as a guide and is positioned around the spring element, ensuring both a secure fit of the spring element on the ball socket and, at the same time, keeping the ball head in the ball socket with minimal play.If the spring element has a chamfer that engages in the ball head neck and is formed with a detent contour, the spring element can follow the shape of the ball socket and engage directly in the ball head neck where the ball head and / or the ball socket ends. The spring element thus essentially surrounds the ball socket in a form-fitting manner and engages directly with the ball head neck. INTERNAL.

[0035] P24172WO November 14, 2025

[0036] Thus, a second safety mechanism for holding the ball head in the ball socket can be provided by the spring element.

[0037] If the bend forms an essentially parallel line to one end of the ball socket, this can again provide an advantage for the spring element. The bend is formed integrally with the spring element and extends towards the ball head above the ball socket. When referring to an "above" and "below" the ball socket, the insertion opening of the ball socket forms the top of the ball socket, and the essentially lower rounded area of ​​the ball socket forms the bottom. The ball socket has a flat upper section into which the retaining ring is mounted and into which the ball head is inserted during assembly. The ball head protrudes from the upper section of the ball socket with its neck. The neck of the ball head is typically designed with a smaller diameter than the ball itself to allow the ball head to pivot within the ball socket.The design of the spring element as a spring ring offers the possibility that the spring element can move with the ball head, so that on the one hand a secure holding of the ball head in the ball socket can be ensured and on the other hand the ball head can be held with play in the ball socket.

[0038] If the spring element, in its axial extent, covers the ball socket, at least partially, preferably completely on both sides, a further embodiment of the invention results. The axial extent of the spring steel strip is preferably designed such that an INTERNAL

[0039] P24172WO November 14, 2025 Secure mounting of the spring element on the ball joint can be ensured. Furthermore, a guide for insertion is preferably provided on both sides of the spring element, as well as a detent contour, so that the axial extension of the spring steel strip advantageously projects beyond the ball socket on both sides. A symmetrical design of the spring strip prevents assembly errors, thus enabling easy and secure mounting of the spring element and ensuring a secure hold on the ball socket due to the ring shape of the spring element.

[0040] The invention is explained in more detail below with reference to the accompanying drawings and a preferred embodiment. However, it is important to note that this embodiment does not limit the invention but merely represents an advantageous configuration. The features shown can be implemented individually or in combination with other features described in the patent claims.

[0041] It shows:

[0042] Fig. 1 shows a three-dimensional view of a drive carriage in a linear guide, wherein the drive carriage is connected to a drive cable on both sides by ball joints,

[0043] Fig. 2 shows a section through a ball joint connection between the drive cable and the drive carriage, INTERNAL

[0044] P24172WO 13 14 November 2025

[0045] Fig. 3 shows a spring element designed according to the invention in a three-dimensional view and

[0046] Fig. 4 shows a mounted spring element on a ball joint connection, detached from the drive slide.

[0047] Figure 1 shows a part of a sliding door drive 1 in a motor vehicle 2. A drive carriage 3 is shown, which is movable by a drive cable 4. The drive carriage 3 is movably mounted in a guide track 5 by means of a guide roller. The guide roller is, for example, held in the drive carriage 3 by means of ball bearings. The drive carriage comprises the cable receptacles 7, 8, a base plate 9, a connecting plate 10, and the connecting element 11. A door (not shown) can, for example, be attached to the connecting element 11. The connecting element 11 is pivotably mounted in the base plate 9. The cable receptacles 7, 8 are integrally formed with the bearing point for the guide roller. The bolts 12, 13 for mounting the drive cable 4 are installed on the cable receptacles 7, 8.The bolts 12, 13 protrude through the cable receptacles 7, 8 and, together with the ball sockets 14, 15, form the ball joint 16, 17. A further bolt 18, visible in Fig. 1, serves to support another guide roller in the guide track 5. Thus, Fig. 1 shows the connection of the drive cable 4 to the drive carriage 3 in an end position of the drive carriage 3, e.g., in the closed position of a sliding door.

[0048] Fig. 2 shows an exemplary and enlarged ball joint 16, 17 with a spring element 20 INTERNAL.

[0049] P24172WO 14 November 14, 2025. A ball socket 14, 15 is shown into which a ball head 21 has been inserted, the ball head 21 being held in the ball socket 14, 15 by means of a retaining ring 22. As can be clearly seen in Fig. 2, the ball head 21 has a first reduction in diameter 23 into which the retaining ring 22 engages. The ball head neck 24 is adjacent to the diameter reduction 23. The ball head neck 24 in turn transitions into the cylindrical part of the bolt 12, 13. The bolt 12, 13 is positively and force-fitted in the cable receptacles 7, 8, as shown in Fig. 1.

[0050] The ball socket 14, 15 is enclosed by the spring element 20, which has an annular section 26 and a chamfer 27. The chamfer 27 has a detent contour 28, which in turn engages the ball head neck 24 in a form-fitting manner. The annular section 26 of the spring element 20 engages the ball socket 14, 15 in a form-fitting manner and is supported on a lower surface 29 of the ball socket 14, 15. The chamfer 27, in turn, engages a top surface 30 of the ball head 14, 15 and secures the position of the spring element 20 by means of this form-fitting engagement. The spring force of the spring element 20 ensures that the spring element 20 engages the ball socket 14, 15 securely and quietly, and simultaneously acts on the ball head 21 by means of the force of the spring element.

[0051] If, as shown in Fig. 2, a deviation from parallelism occurs between the ball socket 14, 15 and the rope receptacles 7, 8, the ball socket 14, 15 pivots by the angle α. In this extreme situation, the retaining ring 22 must stabilize and hold the ball head 21. An INTERNAL

[0052] P24172WO 15 14 November 2025 additional spring force is exerted on the ball head neck 24 via the spring element 20, so that two complementary locking elements 22, 24 are present to secure the position of the ball head 21 in the ball socket 14, 15 and return the ball head to the parallel starting position to the rope receptacle 7, 8 .

[0053] In Fig. 3, the spring element 20 is shown as a separate component, detached from the ball socket 14, 15. Visible are the annular area 26, the chamfer 27, the locking contour 28, and the insertion aids 31, 32 arranged on both sides. The symmetrical design of the spring element 20 is illustrated by the symmetry line S. The ball head neck 24 can be received by means of the locking contour 28, while the insertion aids 31, 32 serve to facilitate the assembly of the spring element 20.

[0054] Figure 4 shows the mounted spring element 20 on the ball socket 14, 15, released from the cable receptacles 7, 8. It can be seen that the spring element 20 extends axially beyond the ball socket 14, 15. In the direction of the drive cable 4, the spring element 20 also extends beyond the ball socket 14, 15, reaching a crimping area 33 for connecting the drive cable 4 to the ball socket 14, 15. The use of the spring element 20 provides additional security for the ball joint connection 16, 17, enabling the sliding door drive 1 to be equipped with a locking element 20 with minimal design effort and without any modifications to the design. INTERNAL

[0055] P24172WO November 14, 2025

[0056] Reference symbol list

[0057] 1 sliding door drive

[0058] 2 motor vehicle

[0059] 3 drive carriages

[0060] 4 drive rope

[0061] 5 Guide track

[0062] 6, 19 Leadership role

[0063] 7, 8 rope attachments

[0064] 9 Base plate

[0065] 10 Connecting plate

[0066] 11 Connection element

[0067] 12, 13, 18 bolts

[0068] 14, 15 ball trap

[0069] 16, 17 Ball joint

[0070] 20 spring element

[0071] 21 ball head

[0072] 22 retaining ring

[0073] 23 Diameter reduction

[0074] 24 Ball joint neck

[0075] 25 cylindrical part

[0076] 26 ring-shaped area

[0077] 27 bend

[0078] 28 Rast contour

[0079] 29 Underside

[0080] 30 Top

[0081] 31, 32 Insertion aid

[0082] 33 Grouting area

[0083] S symmetry line

Claims

INTERNAL P24172WO 17 14 November 2025 Patent claims 1. Motor vehicle sliding door drive (1) comprising an electric drive with a gearbox downstream of the drive and a cable drum, a sliding door element arranged on the motor vehicle, a drive carriage (3) for the door element, wherein the drive carriage (3) is connected to the electric drive by at least one drive cable (4), and the drive cable (4) is connected to the drive carriage (3) via ball joint connections (16, 17) and a ball head (21) of the ball head connection (16, 17) is held in a ball socket (14, 15) by means of a retaining ring (22), characterized in that the ball head (21) is held in the ball socket (14, 15) by means of at least one further spring element (20).

2. Sliding door drive (1) according to claim 1, characterized in that the further spring element (20) can be mounted from the outside via the ball socket (14, 15).

3. Sliding door drive (1) , according to one of claims 1 to 2, characterized in that the spring element (20) fully overlaps the ball socket (14, 15).

4. Sliding door drive (1) according to one of claims 1 to 3, characterized in that the spring element (20) is designed as a spring steel strip (20).

5. Sliding door drive (1) according to one of claims 1 to 4, characterized in that the spring element (20) INTERNAL P24172WO 18 14 November 2025 is designed to be snapped into a ball-head neck (24) so ​​that a snap contour (28) is formed.

6. Sliding door drive (1) according to one of claims 1 to 5, characterized in that the spring element (20) has at least one insertion aid (31, 32), preferably arranged on both sides.

7. Sliding door drive (1) according to one of claims 1 to 6, characterized in that the spring element (20) has a symmetrical structure.

8. Sliding door drive (1) according to one of claims 1 to 7, characterized in that the spring element (20) is essentially designed as a spring ring (20), wherein the spring element (20) has a chamfer (27) in the area of ​​the detent contour (28).

9. Sliding door drive (1) according to one of claims 1 to 8, characterized in that the bend (27) forms a substantially parallel plane to an upper end (30) of the ball socket (14, 15).

10. Sliding door drive (1) according to one of claims 1 to 9, characterized in that the spring element (20) completely covers the ball socket (14, 15) in its axial extension.

Images