Drive device and assembly method

Abstract

Drive device (A) comprising: o a component assembly comprising a carrier (2) with a receptacle (20) and a retaining pin (1) for mounting in the receptacle (20), the retaining pin (1) comprising: - a cylindrical base body (10) with a cylinder axis (Z) and a lateral surface (M) and - at least one projection (11) extending radially outwards from the cylindrical surface (M) and forming a cutting edge (110), which is designed to cut into a radially inwards projecting material area (201) of the receptacle (20) when the retaining pin (1) is rotated in the receptacle (20) about the cylinder axis (Z) and while maintaining its axial position relative to the receptacle (20) in such a way as to prevent axial displacement of the retaining pin (1), wherein the projection (11) extends in the circumferential direction (U) along a section of the cylindrical surface (M) and within a plane perpendicular to the cylinder axis (Z), wherein the retaining pin (1) can be axially inserted into the receptacle (20) and the receptacle (20) has an inner contour shaped to fit the cylindrical surface (M) and the at least one projection (11) of the retaining pin (1) and has at least one inwardly projecting material area (201) into which the projection (11) of the retaining pin (1) can cut when the retaining pin (1) inserted into the receptacle (20) is rotated about its cylindrical axis (Z) in order to fasten the retaining pin (1) to the carrier (2), and a shaft (3) which is mounted at a bearing point (21) of the carrier (2) of the assembly, wherein the retaining pin (1) can be inserted into the receptacle (20) in such a way that it can act directly or indirectly on an axial end (30) of the shaft (3).

Description

[0001] The invention relates to a drive device according to claim 1 and a method.

[0002] Components are generally manufactured with specific tolerances. When components with tolerances are assembled, play often results. Especially in moving components, such play can lead to noise. For example, a worm shaft in a worm gear may have axial play in its bearings, which can cause noise, for instance, when the direction of rotation changes. To avoid such noise, the axial play can be compensated for by using spring elements such as rubber springs, as described in the introduction to DE 19 537 503 A1.

[0003] However, such spring elements can have the disadvantage of exerting pressure on the shaft, thus hindering its rotation. This can result in reduced gearbox efficiency. Furthermore, such springs can cause a reversing shock, particularly when a drive motor changes direction, for example, due to preloading of the spring in one direction by the drive motor. This can generate a noticeable noise. In many applications, however, the quietest possible operation is desirable.

[0004] Vargus's "TM Solid Solid Carbide Thread Milling Tool", 4th edition, 2012, describes various thread milling tools. Some thread milling tools have helical flutes, others straight flutes.

[0005] DE 698 04 135 T2 describes a geared motor for driving automotive accessories, with means for eliminating the axial play of its shaft. A metallic plug is provided, the diameter of which is larger than the diameter of an axial receptacle formed in a wall of a gearbox housing.

[0006] US Patent 2,976,088 A describes a device for preventing end play in the shaft of a dynamo-electric machine with a pin having an external thread.

[0007] US 2010 / 196091 A1, JP 2016-3727 A, JP 2009-270615 A, US 2013 / 017014 A1 and US 4,770,560 A each describe retaining components with outwardly projecting protrusions for attachment to a corresponding support.

[0008] The object of the present invention is to enable improved axial play compensation.

[0009] This problem is solved by an object having the features of claim 1.

[0010] A drive device with axial play compensation is then provided. The drive device comprises an assembly and a shaft rotatably mounted at a bearing point of the assembly's support. The assembly includes a support with a receptacle and a retaining pin for mounting in the receptacle, which can be used, for example, to compensate for the axial play of the shaft. The retaining pin comprises a cylindrical base body with a cylindrical axis and an outer surface, and at least one projection extending radially outward from the outer surface and forming a cutting edge.The projection is designed to cut into a radially inwardly projecting material area of ​​the receptacle by means of its cutting edge when the retaining pin (arranged in the receptacle) is rotated about its cylindrical axis and while maintaining its axial position relative to the receptacle, such that axial displacement of the retaining pin is prevented, wherein the projection extends circumferentially along a section of the cylindrical surface and within a plane perpendicular to the cylindrical axis, wherein the retaining pin can be axially inserted into the receptacle and the receptacle has an inner contour shaped to fit the cylindrical surface and the at least one projection of the retaining pin and has at least one inwardly projecting material area into which the projection of the retaining pin can cut when the retaining pin inserted into the receptacle is rotated about its cylindrical axis in order to secure the retaining pin to the carrier.The shaft is mounted at a bearing point of the carrier of the assembly, wherein the retaining pin can be inserted into the receptacle in such a way that it can act directly or indirectly on an axial end of the shaft.

[0011] Such a self-tapping retaining pin can be inserted into a correspondingly shaped receptacle precisely until any existing play is compensated. In this position, the retaining pin can be secured in the receptacle. This securing is possible without exerting any axial force, or with a negligible axial force (along the cylinder axis of the retaining pin), for example, on a shaft supported by the retaining pin with zero axial play. This reduces or completely eliminates noise during shaft operation. Furthermore, it enables particularly smooth shaft operation, which can lead to improved device efficiency. The axial play compensation is thus improved, in particular, by enabling reduced noise and simultaneously enhanced efficiency.

[0012] The projection can be shaped like a milling tooth. For example, the projection is shaped like the milling tooth of a tap for an internal thread, with the difference that the projection of the retaining pin has no pitch (i.e., it follows a circular arc and not a helix). A milling tooth can cut particularly effectively.

[0013] The retaining pin can have a large number of projections for particularly secure attachment to the mount, e.g., more than ten projections. Optionally, all of these projections can have the same shape.

[0014] In one embodiment, several projections arranged offset from each other along the cylinder axis form a group of projections.

[0015] Furthermore, several groups of projections, particularly those offset from one another in the circumferential direction, can be provided, enabling a particularly uniform cut. Optionally, (exactly) three groups of projections are provided. This allows for a particularly symmetrical cut without tilting.

[0016] The retaining pin may include a tool interface formed at one axial end of the retaining pin (e.g. Torx, hex socket, slot or cross recess) and / or a stop surface formed at one (other) axial end.

[0017] Optionally, the carrier can be designed as a housing, e.g. as a gearbox housing for an adjustment drive.

[0018] The retaining pin can be rotated around its cylindrical axis relative to the receptacle at various insertion depths within the carrier. This allows the pin's projection to engage with the internally projecting material of the receptacle at each insertion depth, securing the pin to the carrier at that depth. Depending on the existing axial play, the retaining pin can be inserted deeper or shallower into the receptacle and then secured in this position by rotation. Elastic spring elements are no longer required.

[0019] The retaining pin has an outer contour that matches the inner contour of the receptacle. The inner contour is defined in particular by the inwardly projecting material areas and the pockets formed between them, while the outer contour is defined by the outer surface and the projections.

[0020] The retaining pin can be inserted into the receptacle in such a way that it can act directly or indirectly on an axial end of the shaft, e.g., by being brought into contact with it or by bringing an intermediate component into contact with it.

[0021] Optionally, a positive-locking receptacle is formed on the carrier and a positive-locking insert is provided, wherein the positive-locking insert can be inserted into the positive-locking receptacle in such a way that it is positively locked against rotation relative to the positive-locking receptacle (in particular against rotation about the cylinder axis of the retaining pin arranged in the receptacle). The positive-locking insert can prevent a rotation of the shaft from unintentionally releasing the retaining pin secured in the receptacle.

[0022] The positive locking mechanism is located, for example, between the receptacle for the retaining pin and the bearing point.

[0023] The positive locking insert can be inserted into the positive locking receptacle in such a way that it can be brought into contact with the axial end of the shaft by inserting the retaining pin into the receptacle in order to compensate for any possible axial play.

[0024] The retaining pin can be fixed in the receptacle by rotating it around its cylindrical axis in a position where the positive locking insert is in contact (or almost in contact) with the axial end of the shaft and the retaining pin, in order to mount the shaft axially free of play on the support.

[0025] Optionally, the shaft can be designed as a worm shaft. The drive device includes, for example, a worm gear.

[0026] According to one aspect, a method for mounting the retaining pin on the carrier of the drive device is provided according to any embodiment described herein. The method comprises the following steps: first, the retaining pin is inserted into the receptacle of the carrier; then, the retaining pin is rotated about its cylindrical axis relative to the receptacle such that at least one projection of the retaining pin cuts into at least one inwardly projecting material area of ​​the receptacle, thereby securing the retaining pin to the carrier.

[0027] The support has a bearing point for a shaft and is designed in such a way that the retaining pin can be inserted into the receptacle in such a way that it can act directly or indirectly on an axial end of the shaft supported at the bearing point, and wherein the retaining pin is inserted so deeply into the receptacle that the shaft is supported on the support without axial play as a result of this action.

[0028] The underlying concept of the invention will be explained in more detail below with reference to the exemplary embodiments shown in the figures. These are shown in schematic representations: Fig. 1 a retaining pin for axial play compensation; Fig. 2 a drive device in the form of an adjustment drive for a vehicle component with the retaining pin according to Fig. 1; Fig. 3A and Fig. 3B Views of the drive device according to Fig. 2 in a first stage of assembly; Fig. 4A and Fig. 4B Views of the drive device according to Fig. 2 in a second stage of assembly; Fig. 5 a vehicle seat with the drive device according to Fig. 2 to 4B; and Fig. 6 a motor vehicle with multiple drive devices according to Fig. 2 to 4B.

[0029] Fig. Figure 1 shows a retaining pin 1. The retaining pin 1 has a base body 10 which has a substantially circular cylindrical shape. The base body 10 has a cylindrical axis Z, a lateral surface M and two opposing axial ends.

[0030] Several projections 11, in the form of milling teeth, extend radially outwards from the cylindrical surface M and along the circumferential direction U around the cylinder axis Z. The projections 11 are arranged in groups G1-G3, specifically in three groups G1-G3, which are offset from each other by 120° in the circumferential direction U. Each group G1-G3 comprises a plurality of projections 11, which are equidistant from each other along the cylinder axis Z. Each projection 11 has the shape of a rib that tapers to a sharp point like a blade. The projections 11 each include at least one cutting edge 110, in this case, one cutting edge 110 at each end in the circumferential direction U.

[0031] When the retaining pin 1 is inserted into a receptacle that has an internal contour shaped to match the cylindrical surface M and the projections 11, and then rotated in the receptacle about its cylindrical axis Z, the projections 11 with their cutting edges 110 cut into the material of the receptacle, thus securing the retaining pin 1 to the receptacle. This cutting occurs without axial feed. Therefore, the retaining pin 1 can be inserted into the receptacle (with a force approaching zero N) and secured at this insertion depth to achieve optimal clearance compensation for adjacent components.

[0032] The retaining pin 1 is a single piece and is made of metal, for example steel. The retaining pin 1 has the shape of a pin.

[0033] Fig. Figure 2 shows an assembly comprising the retaining pin 1 according to Fig. 1 and a support 2, which here is designed in the form of a housing, specifically a gearbox housing. A shaft 3 in the form of a worm shaft is rotatably mounted in the gearbox housing and is in gearbox connection with a worm gear. The shaft 3 is guided by a Fig. The assembly is driven by two electric motors (not shown). It is therefore part of a drive device A.

[0034] Several manufacturing tolerances combine in the bearing arrangement of shaft 3, namely in particular those of shaft 3 itself, those of the support 2, and those of a positive-locking insert 4 against which shaft 3 can be axially supported. These tolerances can lead to axial play.

[0035] To compensate for this axial play, the retaining pin 1 is used, which can be inserted into a receptacle 20 of the support 2 that is aligned coaxially with the axis of rotation of the shaft 3. For this purpose, the retaining pin 1 is inserted into the receptacle 20, as shown in Fig. 2 illustrated by means of an arrow. As in Fig. As shown in Figure 2, the receptacle 20 has an inner contour that matches the retaining pin 1 inserted in the axial direction.

[0036] Fig. 3A and Fig. Figure 3B shows the retaining pin 1 during the insertion process. The inner contour of the receptacle 20 is defined by pockets 200 and material areas 201 projecting radially inwards from the pockets 200. In this case, the receptacle comprises three pockets 200 and three inwardly projecting material areas 201. The inwardly projecting material areas 201 each describe a section of a cylindrical surface and guide the retaining pin 1 along its cylindrical surface M. The pockets 200 receive the projections 11.

[0037] In the intermediate position according to Fig. In Figure 3B, the retaining pin 1 is in contact with the positive-locking insert 4, which is still arranged at a distance from an axial end 30 of the shaft 3. The positive-locking insert 4 is displaceable along an axis and positively locked against rotation about this axis in a positive-locking receptacle 22 of the carrier 2. As shown in particular in Fig. As can be seen in 2, the positive locking insert 4 in the present example is essentially star-shaped.

[0038] The receptacle 20, the axis of the positive locking receptacle 22 and the shaft 3 mounted at the bearing point 21 are aligned coaxially to each other.

[0039] The retaining pin 1 is opposite Fig. 3B is inserted even deeper into the receptacle 20 until the retaining pin 1 with a stop surface 13 is struck against the positive locking insert 4 and the positive locking insert 4 is in contact with the axial end of the shaft 3.

[0040] The retaining pin 1 is then rotated in the receptacle 20, as shown in Fig. Figure 4A illustrates this with an arrow. Here, the projections 11 with their cutting edges 110 cut into the inwardly projecting material areas 201 of the receptacle 20. For example, a rotation of 50° to 70° is performed. The rotation is carried out, for example, by means of a tool that fits the tool interface 12 provided at the axial end of the retaining pin 1.

[0041] The rotation of the retaining pin 1 does not result in any axial displacement of the retaining pin 1, so that it is possible to fix the positive locking insert 4 without play, but essentially without axial forces.

[0042] The Fig. 4A and Fig. Figure 4B shows the projections 11 cut into the material of the inwardly projecting material areas 201. The projections 11 can also be described as teeth. The cut projections 11 prevent, in particular, axial displacement of the retaining pin 1.

[0043] The carrier 2 is made of a softer material compared to the retaining pin 1, e.g. aluminum or plastic.

[0044] The positive locking insert 4 absorbs a torque from the shaft 3.

[0045] Since shaft 3 is mounted with virtually no axial play, very little noise is generated during operation. Furthermore, shaft 3 can rotate particularly easily because it is not subjected to an axial force from a spring element or the like.

[0046] Fig. Figure 5 shows an adjustable vehicle seat. The vehicle seat comprises a seat base with several side panels, of which in Fig. 5 only one is shown, and one in Fig. The vehicle seat 5 includes a backrest, which is shown in 5 dashed lines. Furthermore, the vehicle seat 5 comprises a backrest which is in Fig. Figure 5 is only indicated. The vehicle seat 5 includes the drive device A, used here to adjust the position of the seat cushion relative to the side panels 50. For this purpose, the drive device A is mounted on one side panel 50 and coupled to an adjustment mechanism 52 via a Bowden cable. When the adjustment mechanism 52 is moved by activating the drive device A, the position of a crossbar 51 supporting the seat cushion is changed relative to the side panels 50. This allows, for example, the seat height to be adjusted or an easy-entry function to be provided.

[0047] The vehicle seat 5 also includes a longitudinal adjustment device 53, which can optionally also be operated by means of a drive device A according to Fig. 2 to 4B is adjustable. Furthermore, the inclination of the backrest relative to the seat is adjustable. For this purpose, the vehicle seat can also be equipped with a drive device A, e.g., coupled with a corresponding tilt adjuster, according to Fig. 2 to 4B. Other possible adjustment functions of the vehicle seat 5 can also be coupled with such a drive device A, e.g. a seat depth adjustment and / or an adjustable lumbar support.

[0048] Fig. Figure 5 further shows a drive motor 6 of the drive device A, which here is designed in the form of an electric motor.

[0049] Fig. Figure 6 shows a motor vehicle 7 with multiple drive devices A according to Fig. 2 to 4B.

[0050] A drive device A is operatively connected to a window regulator 700 of a door 70 of the motor vehicle 7. The drive device, for example, drives the actuator of the window regulator 700 to move a window pane in the door 70 up and down.

[0051] Another drive unit A is coupled to a door lock 701. The door lock 701 can be unlocked and locked by means of this drive unit A.

[0052] A drive device A is also coupled to a trunk lid 71 of the motor vehicle. By activating this drive device A, the trunk lid 71 can be opened and closed.

[0053] Alternatively or additionally, the motor vehicle 7 can include retaining pins 1 at several locations, optionally also without an associated drive device A, e.g. at locations where axial play needs to be adjusted and / or where fixation in a specific axial position is required, e.g. generally in the case of drives, controls and sensors, in particular their arrangement in the vehicle 7. Reference symbol list 1 retaining pin 10 basic shapes 11 lead 110 cutting edge 12 Tool interface 13 Stop surface 2 carriers 20 recordings 200 bags 201 Material area 21 storage location 22 Form-fit recording 3rd wave 30 axial end 4 Form-fitting insert 5 vehicle seats 50 side panel 51 Cross brace 52 Adjustment mechanism 53 Longitudinal adjustment device 6 Drive motor 7 Motor vehicle 70 Door 700 window regulators 701 Door lock 71 Trunk lid A drive device G1-G3 group of protrusions M surface area U circumferential direction Z cylinder axis

Claims

[1] Drive device (A) comprising: o an assembly comprising a carrier (2) with a receptacle (20) and a retaining pin (1) for mounting in the receptacle (20), the retaining pin (1) comprising: - a cylindrical base body (10) with a cylinder axis (Z) and a lateral surface (M) and - at least one projection (11) extending radially outwards from the cylindrical surface (M) and forming a cutting edge (110), which is designed to cut into a radially inwards projecting material area (201) of the receptacle (20) when the retaining pin (1) is rotated in the receptacle (20) about the cylinder axis (Z) and while maintaining its axial position relative to the receptacle (20) in such a way as to prevent axial displacement of the retaining pin (1), wherein the projection (11) extends in the circumferential direction (U) along a section of the cylindrical surface (M) and within a plane perpendicular to the cylinder axis (Z), wherein the retaining pin (1) can be axially inserted into the receptacle (20) and the receptacle (20) has an inner contour shaped to fit the cylindrical surface (M) and the at least one projection (11) of the retaining pin (1) and has at least one inwardly projecting material area (201) into which the projection (11) of the retaining pin (1) can cut when the retaining pin (1) inserted into the receptacle (20) is rotated about its cylindrical axis (Z) in order to fasten the retaining pin (1) to the carrier (2), and a shaft (3) which is mounted at a bearing point (21) of the carrier (2) of the assembly, wherein the retaining pin (1) can be inserted into the receptacle (20) in such a way that it can act directly or indirectly on an axial end (30) of the shaft (3). [2] Drive device (A) according to claim 1, characterized by , that the projection (11) of the retaining pin (1) is designed as a milling tooth. [3] Drive device (A) according to one of the preceding claims, characterized by a multitude of projections (11) on the retaining pin (1). [4] Drive device (A) according to any of the preceding claims, characterized by , that several projections (11) of the retaining pin (1) arranged offset from each other along the cylinder axis (Z) form a group (G1-G3) of projections (11). [5] Drive device (A) according to claim 4, characterized by several groups (G1-G3) of projections (11) of the retaining pin (1) arranged in circumferential direction (U) offset from each other. [6] Drive device (A) according to any of the preceding claims, characterized by a tool interface (12) formed at one axial end of the retaining pin (1) and a stop surface (13) formed at the other axial end of the retaining pin (1). [7] Drive device (A) according to any of the preceding claims, characterized by , that the carrier (2) is designed as a housing. [8] Drive device (A) according to any of the preceding claims, characterized by , that the retaining pin (1) can be rotated about its cylindrical axis (Z) relative to the receptacle (20) at different insertion depths in the receptacle (20) of the carrier (2), so that the projection (11) of the retaining pin (1) can cut into the internally projecting material area (201) of the receptacle (20) in order to secure the retaining pin (1) to the carrier (2) at the respective insertion depth. [9] Drive device (A) according to any of the preceding claims, characterized by a positive locking receptacle (22) on the carrier (2) and a positive locking insert (4) which can be inserted into the positive locking receptacle (22) in such a way that it is positively locked against rotation relative to the positive locking receptacle (22). [10] Drive device (A) according to claim 9, characterized by , that the positive locking receptacle (22) is arranged between the receptacle (20) for the retaining pin (1) and the bearing point (21). [11] Drive device (A) according to claim 9 or 10, characterized by , that the positive locking insert (4) can be inserted into the positive locking receptacle (22) in such a way that it can be brought into contact with an axial end (30) of the shaft (3) by inserting the retaining pin (1) into the receptacle (20). [12] Drive device (A) according to claim 11, characterized by , that the retaining pin (1) in a position in which the positive locking insert (4) is in contact with the axial end (30) of the shaft (3) and the retaining pin (1) can be fixed in the receptacle (20) by a rotation about its cylindrical axis (Z) in order to support the shaft (3) axially without play on the support (2). [13] Drive device (A) according to any of the preceding claims, characterized by , that the shaft (3) is designed as a worm shaft. [14] Method for mounting the retaining pin (1) of the drive device (A) according to one of the preceding claims on the carrier (2) of the drive device (A), comprising the following steps: - Inserting the retaining pin (1) into the receptacle (20) of the carrier (2), - Rotating the retaining pin (1) about its cylindrical axis (Z) relative to the receptacle (20) such that at least one projection (11) of the retaining pin (1) cuts into at least one inwardly projecting material area (201) of the receptacle (20), so that the retaining pin (1) is attached to the carrier (2), wherein the retaining pin (1) is inserted into the receptacle (20) to such an extent that the shaft (3) is supported on the carrier (2) without axial play.

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