DRIVE FOR ADJUSTING AN ADJUSTING ELEMENT OF A MOTOR VEHICLE

Description

[0001] The invention relates to a drive for adjusting an adjusting element, in particular a flap, of a motor vehicle according to the preamble of claim 1 and to a method for assembling a drive according to claim 14.

[0002] The term "adjustment element" is to be understood broadly in this context. It includes, for example, flaps such as tailgates, trunk lids, hoods, side doors, cargo area flaps, or the like, or sliding doors of a motor vehicle.

[0003] Different drive types are known for adjusting such an adjustment element, for example, a tailgate. Motor-driven, motorless, and especially spring-driven drives are known. A motor-driven drive, for example, is a spindle drive, which uses a drive motor to drive a spindle-spindle nut gear as a feed gear to generate linear drive movements. A motorless drive, in particular, comprises a gas spring, which has a drive unit with a gas-filled gas spring cylinder and an axially guided gas spring piston rod—i.e., a push rod with a piston at one end. The gas filled in the cylinder is then pressurized, thereby providing the spring force.This drive unit can additionally be supported by a drive spring arrangement with at least one drive spring, in particular a helical spring, for example a helical compression spring, which provides an additional spring force.

[0004] The known drive (DE 10 2008 061 117 A1), from which the invention is based, has such a drive unit in the form of a gas pressure spring. The drive unit is radially surrounded by a drive spring arrangement with a drive spring in the form of a helical compression spring. To transmit linear drive movements to the motor vehicle, the drive has two joint parts that are adjustable relative to one another along a geometric drive axis between a retracted position and an extended position. Each joint part, with a counter-joint part on the motor vehicle side, forms a drive connection for coupling to the adjustment element on the one hand and the rest of the motor vehicle on the other hand. One joint part is axially fixedly coupled to a hollow cylinder of the drive unit, namely the gas pressure spring cylinder, and the other joint part is axially fixedly coupled to a rod of the drive unit, namely the rod provided with the gas pressure spring piston.A metal plate is provided between each joint part and the drive unit, on which the drive spring of the drive spring arrangement is axially supported in order to transmit the spring force to the joint parts.

[0005] The drive housing, which is made of a plastic material, is angled inward at both axial ends, thus forming a base that secures the respective metal plate towards the joint part against the spring force of the drive spring assembly. When mounted on the vehicle, the two joint parts themselves provide further axial security; each is coupled to the associated component of the gas spring, i.e., the gas spring cylinder on the one hand, and the gas spring piston rod on the other. However, the problem is that if the housing and the joint parts are damaged, for example in the event of a fire, there is a risk of unintentional expansion of the drive spring of the drive spring assembly, as the two metal plates may then no longer have any, or at least insufficient, axial hold.

[0006] It is also known to provide metal bodies for the axial support of a drive spring of a drive spring assembly. These metal bodies are crimped to the drive unit components that transmit the drive force, i.e., the hollow cylinder and the rod axially guided therein. This secures the metal bodies axially to the drive unit and thereby prevents unwanted expansion of the drive spring. These metal bodies are then typically overmolded with plastic material to form the associated joint part. Such a drive has a relatively complex structure and comprises a large number of parts.

[0007] Other known drives are known from DE 10 2018 117 889 A1, US 9,360,077 B2, DE 10 2016 214 837 A1 and DE 10 2014 201 941 A1.

[0008] The invention is based on the problem of designing and developing the known drive in such a way that a high level of operational reliability is ensured while at the same time maintaining a simple structure.

[0009] The above problem is solved in a drive for adjusting an adjusting element, in particular a flap, of a motor vehicle according to the preamble of claim 1 by the features of the characterizing part of claim 1.

[0010] The fundamental idea is to axially secure the spring assembly to the associated drive force-transmitting component of the drive unit using a locking element. The locking element projects radially into the imaginary extension of the spring material, i.e., the spring wire forming the spring coils, of the drive spring assembly, particularly the axially closest drive spring. The term "axial" refers to the direction of the spring centerline or geometric drive axis. The imaginary extension, hereinafter referred to as "projection," of the spring material runs here and preferably in a ring around the geometric drive axis. On the one hand, this ensures particularly simple assembly, since the respective locking element only needs to be screwed on. On the other hand, the usually robustly designed component of the drive unit will not melt, or at least not as quickly, in the event of a fire.If the safety element is also designed to be fireproof, the joint part can melt away without the spring arrangement causing any danger.

[0011] In detail, it is proposed that in the assembled state at least one of the components of the drive unit, in particular both components of the drive unit, is or are axially fixedly coupled to a securing element via a threaded connection, and that the securing element projects radially into an axial projection of a spring material of the drive spring arrangement.

[0012] The provision of a threaded connection results in not only the securing function but also a simple assembly in combination with a stable connection, which is provided in particular directly between the securing element and the component of the drive unit.

[0013] It is intended that a component of the drive unit is connected to the associated joint part via the securing element. This results in particularly simple assembly of the joint part and the securing element to the component of the drive unit, especially if both can be screwed on together.

[0014] Claim 2 concerns the preferred arrangement of the securing element along the drive shaft. This provides effective securing combined with simple assembly.

[0015] Claim 3 relates to preferred embodiments of the shape of the securing element, which are selected such that the securing element, and thus the component of the drive unit, is preferably secured against rotation relative to the joint part. A further possibility for implementing a rotation lock arises from claim 8, particularly in combination with claims 5 to 7.

[0016] Claim 4 relates to an axial extension of the hollow cylinder, onto which the securing element can be screwed. Claims 5 and 6 further provide a configuration in which the axial extension has an axial end section with a reduced cross-section. This can have several functions. Firstly, it preferably serves as a threading aid during assembly; secondly, it can increase the torque required to loosen the threaded connection when, as proposed in claim 6, it engages with a corresponding receptacle of the associated joint part. In addition, it can serve to center the hollow cylinder relative to the joint part.

[0017] Claim 6 relates to the preferred manner of forming the threaded connection. According to claim 7, the threaded connection can be secured against loosening. In a particularly preferred embodiment, this is achieved via an anti-rotation section, which can be formed by the axial end section.

[0018] Claims 8 and 9 relate to a drive housing and its preferred arrangement. For axial centering of at least one of the components of the drive unit, one of the housing tubes can have a centering collar. This centering collar, particularly in combination with an assembly aid, forms a further preferred embodiment.

[0019] Claim 11 relates to a preferred possibility of water management of the drive.

[0020] Claims 12 and 13 relate to embodiments of the drive spring arrangement, the securing element and the drive unit.

[0021] According to a further teaching according to claim 14, which has independent significance, a method for assembling a drive is claimed. This method serves in particular for assembling a proposed drive. Reference is made to all statements relating to the proposed drive.

[0022] The key to this process is the connection of the inner housing tube with the associated joint part, the drive unit and the spring arrangement, for which the centering collar is provided as an assembly aid.

[0023] Claim 15 concerns the assembly of the securing element.

[0024] The invention is explained in more detail below with reference to a drawing that merely illustrates exemplary embodiments. The drawing shows: Fig. 1 in a schematic perspective view the rear of a motor vehicle with a proposed drive, Fig. 2in a sectional view the proposed drive according to Fig. 1 in a retracted position Fig. 3 in a sectional view the proposed drive according to Fig. 1 in an extended position, Fig. 4 in an enlarged perspective view a detail of the proposed drive according to Fig. 1 in a schematic representation of an assembly process and Fig. 5 in an enlarged perspective view a detail of an alternative embodiment of the proposed drive according to Fig. 1 in a schematic representation of an assembly process.

[0025] The drive 1 shown in the drawing, which is designed as a linear drive, is here, and preferably in a manner to be explained later, configured as a gas spring drive. However, the drive 1 can also be designed as a spindle drive. The explanations for a gas spring drive therefore apply equally to a spindle drive.

[0026] The proposed drive 1, which is designed here as a gas pressure spring drive, serves for the motorless and purely spring-driven adjustment of an adjusting element 2, in particular a flap, of a motor vehicle 3. The adjusting element 2 is according to Fig. 1 a tailgate of the motor vehicle 3. Regarding other embodiments of the adjusting element 2, reference is made to the list in the introductory part of the description. As shown, several, in particular two, drives 1 can also be provided for adjusting the adjusting element 2.

[0027] The drive 1 comprises a drive unit 4, which comprises a hollow cylinder 5 and a rod 6 axially guided therein as drive force-transmitting components. The hollow cylinder 5 and the rod 6 are preloaded against each other, here, among other things, by a gas filled into the hollow cylinder 5, here and preferably in the extended position.

[0028] To transmit linear drive movements to the motor vehicle 3, the drive 1 has two joint parts 8, 9 that are adjustable relative to one another along the geometric drive axis 7 between a retracted position and an extended position, which joint parts 8, 9 are preferably identical in construction. Figures 2 and 3 The upper joint part 8 forms, together with a motor vehicle-side counter-joint part 10, which is arranged here on the adjusting element 2, a drive connection 12 for coupling with the adjusting element 2. The Figures 2 and 3The lower joint part 9, together with a motor vehicle-side counter-joint part 11, which is arranged here on the motor vehicle body, forms a drive connection 13 for coupling to the motor vehicle 3. Here and preferably, the two joint parts 8, 9 each have a ball socket, which are articulated to a ball head of the respective counter-joint part 10, 11. In principle, it is also conceivable for the joint parts 8, 9 to have a ball head and the counter-joint part 10, 11 to have a ball socket.

[0029] Like the enlarged detail views in the Figures 2 and 3 As shown, one joint part 8 is axially fixedly coupled to an associated first of the components 5, 6 of the drive unit 4, here the hollow cylinder 5, and the other joint part 9 is axially fixedly coupled to an associated second of the components 5, 6 of the drive unit 4, here the rod 6, in the assembled state. The axially fixed coupling will be explained in more detail below.

[0030] Furthermore, the proposed drive 1 has a drive spring arrangement 14 with at least one drive spring 15, here precisely one drive spring 15, which acts on the two joint parts 8, 9, i.e. is preloaded thereon. The drive spring arrangement 14 and the gas filled in the hollow cylinder 5 preload the joint parts 8, 9 against each other, here in the extended position. The at least one drive spring 15, here precisely one drive spring 15, is in particular a helical spring and here and preferably a helical compression spring. In principle, according to an embodiment not shown here, it is also conceivable to provide a helical tension spring as part of the drive spring arrangement 14 in addition to or as an alternative to a helical compression spring.

[0031] It is now essential that in the assembled state at least one of the components 5, 6 of the drive unit 4, in particular both components 5, 6 of the drive unit 4, is or are axially fixedly coupled to a securing element 16 via a threaded connection, and that the securing element 16 projects radially into an axial projection P of a spring material of the drive spring arrangement 14.

[0032] Whenever reference is made here and below to the "assembled state," this always refers to the assembled state of the drive. In this state, the axial positive connection between the respective joint part 8, 9 and the associated component 5, 6 exists in both directions, i.e., along the geometric drive axis 7, both in the retracted and extended positions.

[0033] While a securing element 16 is provided here and preferably on both sides along the drive axis 7 so that in the event of a fault, particularly in the event of a fire, the drive spring arrangement 14 and in particular the drive spring 15 are secured against sudden release, it follows from the further explanations that an embodiment in which only a single proposed securing element 16 is provided is also advantageous. This particularly concerns the simple assembly of the securing element 16, which is here and preferably not identical for both joint parts 8, 9. Accordingly, the advantages of assembly on one side may be greater than on the other.

[0034] To perform its securing function, the securing element 16 protrudes radially into the axial projection P of the spring material. This is, in particular, the spring material of the drive spring 15. In the preferred helical spring, which is in particular a helical compression spring, the projection P is the projection of the spring coils at a certain radius from the drive axis 7. The term "spring material" thus refers to the area of ​​the drive spring arrangement 14 in which material of a drive spring 15 is actually present, and in particular the spring coils.

[0035] According to the invention, to simplify assembly, but also to increase the compactness and structural strength of the drive 1, it is provided that a component 5, 6 of the drive unit 4, in particular both components 5, 6 of the drive unit 4, is or are connected via the securing element 16 to the respectively associated joint part 8, 9. From a synopsis of the Figures 2 and 3 It is clear that this is intended for both components 5, 6 of the drive unit 4. This is exemplified in Fig. 4 for the hollow cylinder 5 and the upper joint part 8.

[0036] As in Fig. 4b ), the securing element 16 is accommodated according to the invention in the joint part 8, 9. This and the further explanations, which are made only with regard to one joint part 8, 9, can also apply to the other joint part 8, 9.

[0037] According to the invention, the joint part 8, 9 forms a receptacle 17 into which the securing element 16 is inserted from the radial direction. The insertion process is described in Fig. 4a ) is shown.

[0038] In principle, it is advantageous for the proposed drive 1 if the various components are and remain as centered as possible along the drive axis 7. This applies not only to assembly, but also during operation of the drive 1, for example in the event of icing, this centering can be important to prevent damage to less stable parts, especially plastic parts, if the icing breaks and some of the components of the drive 1 perform a jerky movement. In addition, a well-centered drive 1 allows the use of more cost-effective plastic parts, as these are more precise or subject to less stress. The threaded connection, particularly in combination with the holder 17, contributes to centering the components 5, 6 of the drive unit 4 with respect to the joint part 8, 9.Accordingly, the securing element 16 is here and preferably designed such that it centers the component 5, 6 with respect to the joint part 8, 9, in particular by the threaded connection being aligned along the drive axis 7 and / or coaxial therewith.

[0039] The respective joint part 8, 9 here and preferably has a bearing section 8a, 9a for coupling to the counter-joint part 10, 11, here and preferably a ball socket, and, spaced therefrom, a connecting section 8b, 9b for coupling to the respectively assigned component 5, 6 of the drive unit 4. The bearing section 8a, 9a is connected to the connecting section 8b, 9b via a connecting section 8c, 9c. Particularly preferably, the bearing section 8a, 9a and the connecting section 8c, 9c, preferably also together with the connecting section 8b, 9b, are designed as a one-piece component. Here and preferably, the securing element 16 is received in the connecting section 8b, 9b. This here and preferably forms the receptacle 17.

[0040] With regard to the arrangement of the securing element 16 along the geometric drive axis 7, it is preferably provided here that the securing element 16 is arranged axially between the spring material and at least one section 8a, 8b, 8c, 9a, 9b, 9c, in particular the bearing section 8a, 9a, of the respective joint part 8, 9. It can also be provided that the securing element 16 is arranged between the entire joint part 8, 9 and the spring material.

[0041] Here, and preferably, the securing element 16 is axially coupled, in particular on both sides, with the respective joint part 8, 9 in a form-fitting manner. Here, and preferably, the securing element 16 cannot be moved, or cannot be moved significantly, in the axial direction relative to the respective joint part 8, 9. For this purpose, in particular, the securing element 16 is here, and preferably, in direct contact with the joint part 8, 9.

[0042] It can be provided that the securing element 16, in particular in interaction with the receptacle 17, provides a rotation lock of the securing element 16 relative to the joint part 8, 9, and thus in particular of the component 5, 6 of the drive unit 4 relative to the respectively associated joint part 8, 9.

[0043] In general, the securing element 16 is designed here, preferably in the radial direction, to be flat, in particular disc-shaped. The securing element 16 can have a substantially round radial outer contour. However, it can also be provided that the securing element 16 has a radial outer contour that deviates from a round shape. In particular, the securing element 16 can have a substantially oval or polygonal radial outer contour. This makes it possible for the securing element 16 to be secured against rotation on a counter-element 18, in particular one that is connected in a rotationally fixed manner to the respective joint part 8, 9 or is otherwise designed in one piece with the respective joint part 8, 9. In the exemplary embodiment, the counter-element 18 is the receptacle 17 or is formed by the walls of the receptacle 17.

[0044] As already indicated above, here and preferably the hollow cylinder 5, namely at its axial end facing the associated or coupled joint part 8, is provided with an axial extension 19 which is axially fixed to the hollow cylinder 5.

[0045] The securing element 16 is then screwed onto the axial extension 19, preferably in the assembled state. It is preferably provided here that the rod 6 also has an axial extension 19, which, however, preferably, unlike the hollow cylinder 5, does not have a reduced diameter compared to the rod 6. All statements regarding the axial extension 19 of the hollow cylinder 5 can apply correspondingly to the axial extension 19 of the rod 6.

[0046] Here, and preferably, the axial extension 19 has an axial end portion 20 with a cross-section that is reduced compared to the inner diameter of the securing element 16. By reducing the cross-section, here and preferably the diameter, a threading aid can be provided to simplify the joining of the securing element 16 and the axial extension 19 during assembly. A further preferred function of the axial end portion 20 will be explained below.

[0047] The axial extension 19 and in particular the axial end section 20 is or are here and preferably connected to the hollow cylinder 5 or the rod 6 in a materially bonded, positively bonded and / or non-positively bonded manner or are designed in one piece with the hollow cylinder 5 or the rod 6.

[0048] Here, and preferably, the axial extension 19 and / or the axial end section 20 is in engagement, in particular by force-fitting and / or material-fitting engagement, with a corresponding receptacle 21 of the respectively associated joint part 8, 9. This receptacle 21 of the joint part 8, 9 can fulfill a dual function. On the one hand, it can ensure radial centering of the component 5, 6 of the drive unit 4 relative to the joint part 8, 9 and thus simultaneously of the securing element 16. On the other hand, the axial end section 20 can have a surface contour 22 which, in interaction with the corresponding receptacle 21, provides an anti-twist feature, which also includes an anti-twist feature.In particular, it is provided that the said surface contour 22 is grooved, in particular with several longitudinal grooves, and is made of metal and digs into the receptacle 21 of the joint part 8, 9, which is made in particular of plastic, during a rotational movement.

[0049] By providing two axially spaced contact areas between the component 5, 6 of the drive unit 4 and the respectively associated joint part 8, 9 via the axial end section 20 and the threaded connection with the securing element 16, it is also possible to provide protection against tilting of the drive unit 4 relative to the joint part 8, 9.

[0050] Here and preferably, the hollow cylinder 5, in particular the axial extension 19, and / or the rod 6 has an external thread 23. The securing element 16 here and preferably has a corresponding internal thread 24. The external thread 23 then forms the threaded connection with the internal thread 24 in the assembled state. Here and preferably, a threaded section 25 on the axial extension 19, which forms the external thread 23, adjoins the axial end section 20 when viewed from the outside.

[0051] The threaded connection is preferably secured against loosening, whereby known measures can be used. In particular, the threaded section 25 of the axial extension 19 can have a non-circular cross-section and / or be non-cylindrical in order to increase the loosening torque.

[0052] Additionally or alternatively, the hollow cylinder 5, in particular the axial extension 19, and / or the rod 6 has an anti-rotation section 26, which is in engagement, in particular by force-locking and / or form-locking, with a corresponding receptacle 27 of the respectively associated joint part 8, 9. The anti-rotation section 26 is arranged here and preferably axially outside the threaded section 25. Here and preferably, the axial end section 20 of the axial extension 19 forms the anti-rotation section 26 and / or the receptacle 21 corresponding to the axial end section 20 forms the receptacle 27.

[0053] In a further embodiment, the engagement of the internal thread 24 with the external thread 23 in the release direction can be designed to be self-locking.

[0054] Furthermore, as in particular the Figures 2 and 3To illustrate, the drive 1 comprises a drive housing 28 with two housing tubes 29, 30, here an inner housing tube 29 and an outer housing tube 30, which telescopically intersect when adjusted between the retracted position and the extended position. The two housing tubes 29, 30 are here and preferably axially fixed to a respective one of the joint parts 8, 9. Here, the inner housing tube 29 is connected to the Figures 2 and 3 lower joint part 9 and the housing outer tube 30 to the Figures 2 and 3 upper joint part 8 axially fixed.

[0055] The drive spring assembly 14, which here is formed by a single drive spring 15, but can also be formed by multiple drive springs 15, is arranged here and preferably radially between the drive unit 4 and the drive housing 28. To guide the at least one, and here only, drive spring 15, a spring guide tube 31 is arranged radially between the drive unit 4 and the drive spring assembly 14.

[0056] As shown in the figures, a spacer 32 can also be provided between the drive spring 15 and the respective joint part 8, 9, on which the drive spring 15 is supported.

[0057] The axially fixed connection between the inner housing tube 29 and the associated joint part 9 is achieved here and preferably by an axial positive fit, such that a housing flange 33 is axially fixed between an axial stop of the joint part 9 and the drive spring arrangement 14. This can be provided in addition to the coupling via the securing element 16. Furthermore, it can be provided that the respective housing tube 29, 30, in the assembled state, extends axially beyond the respective securing element 16 and / or radially surrounds the respective securing element 16. The securing element 16 is thus radially secured and not easily accessible from the outside. Since this radial securing is preferably not necessary here, it can also serve purely aesthetic purposes.

[0058] It can also, as the enlarged view in Fig. 3As shown below, at least one of the housing tubes 29, 30, in particular the inner housing tube 29, has a centering collar 34 which runs radially inside the housing tube 29, 30 in the axial direction along the respectively assigned component 5, 6 of the drive unit 4, in particular the axial extension 19 or the rod 6, and preferably forms a receptacle 35 which widens radially in the axial direction for the respectively assigned component 5, 6 as an assembly aid. In the proposed drive 1, the inner housing tube 29 is pushed blindly over the rod 6 during assembly. The centering collar 34 serves to simplify this. This guides the rod 6 through the slope of the receptacle 35.

[0059] Additionally or alternatively, the centering collar 34 can center the respective component 5, 6 with respect to the respective associated joint part 8, 9. This prevents the component 5, 6 from tilting relative to the drive axis 7 and simplifies assembly on the securing element 16 and / or the joint part 8, 9.

[0060] Here, and preferably, the centering collar 34 is integrally connected to the housing tube 29, 30. Here, and preferably, the centering collar 34 is designed to seal in the axial direction. This can improve water management of the drive 1.

[0061] Since the drive 1 on the motor vehicle 3 may come into contact with rainwater, for example, at least one drainage opening 36 is provided for water management here and preferably furthermore on at least one of the housing tubes 29, 30, in particular on the lower housing tube 29, 30 when mounted on the motor vehicle 3. Here and preferably, at least two drainage openings 36, more preferably at least three drainage openings 36, even more preferably at least four drainage openings 36 are provided. The corresponding water flow is in Fig. 3 indicated by arrows.

[0062] The drainage opening 36 fluidically connects an interior of the drive 1 with the environment. In particular, this protects metal parts inside the drive 1 from corrosion. The interior of the drive 1 that is fluidly connected to the environment is preferably the interior that accommodates the drive spring 15. Here, and preferably, the centering collar 34 has at least one drainage opening 37. The drainage opening 37 of the centering collar 34 is in fluidic contact with the drainage opening 36 of the joint part 8, 9.

[0063] Here, and preferably, the respective securing element 16 and / or the at least one drive spring 15 of the drive spring arrangement 14 and / or the respective component 5, 6, i.e., the hollow cylinder 5 or the rod 6, and / or the axial extension 19, are each made of metal. Additionally or alternatively, it is provided here that the respective joint part 8, 9 and / or the respective housing tube 29, 30 are made of a plastic material.

[0064] As already mentioned, here and preferably the drive 1 is designed as a gas spring drive. Here and preferably the drive unit 4 is designed as a gas spring 38, wherein the first component 5 is a gas-filled gas spring cylinder 39 and the second component 6 is a gas spring piston rod 40 axially guided therein. A gas spring piston rod 40 is a unit comprising a push rod 40a and a piston 40b.

[0065] As previously indicated, the proposed drive 1 is not limited to the gas spring drive configuration, but can also be configured as a spindle drive. In this case, the drive unit 4 is configured as a spindle drive unit, with the first component 5 being a spindle nut tube with an axially and rotationally fixed spindle nut, and the second component 6 being a threaded spindle meshing with the spindle nut. Such a spindle-spindle nut transmission is well known and requires no further explanation here. An optional drive motor of the drive unit 4 can then actuate the spindle-spindle nut transmission in the usual way.

[0066] According to a further teaching of independent significance, a method for assembling a drive 1 is proposed. The method is used in particular for assembling a proposed drive 1. Reference may be made to all statements relating to the proposed drive 1.

[0067] A key feature of the method is that the inner housing tube 29 is connected to the associated joint part 9, the drive unit 4, and the spring assembly 14. For this purpose, the inner housing tube 29 is preferably pushed over one of the components 5, 6 of the drive unit 4, in particular the rod 6, and the drive spring 15. In this case, the inner housing tube 29 is centered relative to the component 5, 6 of the drive unit 4 via the centering collar 34.

[0068] The associated joint part 9 can be connected to the inner housing tube 29 before or after sliding it on. It is screwed onto the rod 6, preferably after sliding it on, via the securing element 16. It can be provided that the drive spring 15 is compressed, particularly externally, when sliding the inner housing tube 29 on.

[0069] After connecting the inner housing tube 29 with the associated joint part 9, the drive unit 4 and the spring arrangement 14, here and preferably the securing element 16, as in Fig. 4a ), is inserted into the other joint part 8. The joint part 8 is then screwed via the securing element 16 to the associated component 6 of the drive unit 4, in particular the axial extension 19, to form the threaded connection. Here and preferably during this time, the drive spring 15, as shown in Fig. 4a), compressed. The outer housing tube 30 can then be pushed over the joint part 8 and engages therein. For engagement, the joint part 8 can have a collar 41. Since here and preferably the joint parts 8, 9 are of identical construction in order to save production costs, the collar 41 can also be provided on the other joint part 9. In particular, the centering collar 34 and the associated water management also have their own significance, not only within the context of the method.

[0070] Fig. 5 shows corresponding to Fig. 4 an alternative embodiment of the previously described proposed drive 1 during and after assembly. This drive 1 differs from the one shown in the Figures 2 to 4shown drive 1 in that the securing element 16 is not designed as a single piece, but as a multi-piece, here and preferably as a two-piece. Thus, the securing element 16 is formed here and preferably by a first securing element part 16a and a second securing element part 16b, which together perform the functions of the single-piece securing element 16 of the Figures 2 to 4 namely, on the one hand, the axially fixed coupling of the securing element 16 with the respective components 5, 6 of the drive unit 4 via a threaded connection (first function), and on the other hand, that the securing element 16 projects radially into the axial projection P of the spring material of the drive spring arrangement 14 (second function).

[0071] Here and preferably, the first securing element part 16a is provided for the first function and the second securing element part 16b is provided for the second function.

[0072] For this purpose, the first securing element part 16a is designed in particular as a screw nut with an internal thread 24 corresponding to the external thread 23. On the radially outer side, the first securing element part 16a is non-circular, in particular angular, here as a hexagon, wherein here and preferably in the respective joint part 8, 9, the previously described receptacle 21 is provided, which here corresponds to the first securing element part 16a, in particular to its non-circular radial outer side.

[0073] Furthermore, here and preferably, the second securing element part 16b is designed as a form-fitting element that projects radially into the axial projection P of the spring material of the drive spring assembly 14. Here, the second securing element part 16b is, in particular, a snap-ring-like clamp having two legs, between which, at least in the assembled and here also in the unassembled state, a space is formed, in which the axial extension 19 extends in the assembled state.

[0074] As in Fig. 5a ) is also shown here during assembly preferably, corresponding to the Fig. 4a ), the securing element 16 is first inserted into the associated joint part 8 and then the joint part 8 is screwed via the securing element 16 to the associated component 6 of the drive unit 4, in particular the axial extension 19, to form the threaded connection.

[0075] The insertion of the securing element 16 into the associated joint part 8 here comprises several, in particular two, assembly steps, namely, on the one hand, the axial, in particular rotationally secured, insertion of the first securing element part 16a into the receptacle 21 and, on the other hand, in particular thereafter, the radial insertion of the second securing element part 16b into the receptacle 17. Here and preferably, the second securing element part 16b, in particular with its legs, projects radially into an axial projection of the material of the first securing element part 16a, so that the first securing element part 16a is axially secured in the associated joint part 8.

[0076] The joint part 8 is screwed to the associated component 6 of the drive unit 4, in particular the axial extension 19, via the securing element 16 by screwing the first securing element part 16a to the external thread 23. The external thread 23 and / or the internal thread 24 can be provided with a microencapsulation 42 prior to assembly, which, in the assembled state, prevents or impedes loosening during operation. It is conceivable that the microencapsulation 42 comprises a microencapsulated adhesive that is activated upon screwing.

Claims

1. Drive for adjusting an adjustment element (2), in particular a flap, of a motor vehicle (3), wherein the drive (1) has a drive unit (4) which has a hollow cylinder (5) and a rod (6), which is guided axially therein, as components transmitting a driving force, wherein, in order to conduct linear driving movements to the motor vehicle (3), the drive (1) has two joint parts (8, 9) which are adjustable with respect to each other along a geometrical drive axis (7) between a retracted position and an extended position and which, in each case with a mating joint part (10, 11) on the motor vehicle side, form a drive connection (12, 13) for coupling to the adjustment element (2) at one end and to the motor vehicle (3) furthermore at the other end, wherein, in each case in the mounted state, the one joint part (8) is coupled in an axially fixed manner to an associated first of the components (5, 6) of the drive unit (4), in particular to the hollow cylinder (5), and the other joint part (9) is coupled in an axially fixed manner to an associated second of the components (5, 6) of the drive unit (4), in particular to the rod (6), and wherein the drive (1) has a drive spring assembly (14) having at least one drive spring (15) which acts on the two joint parts (8, 9) , wherein, in the mounted state, at least one of the components (5, 6) of the drive unit (4), in particular both components (5, 6) of the drive unit (4), is or are coupled in an axially fixed manner to a securing element via a threaded connection, and wherein the securing element (16) projects radially into an axial projection (P) of a spring material of the drive spring assembly (14), and wherein one component (5, 6) of the drive unit (4), in particular both components (5, 6) of the drive unit (4), is or are connected to the respectively associated joint part (8, 9) via the securing element (16), and wherein the securing element (16) is accommodated in the joint part (8, 9), characterized in that the joint part (8, 9) forms a receptacle (17) into which the securing element (16) or a securing element part (16b) of the securing element (16) is introduced from the radial direction.

2. Drive according to Claim 1, characterized in that the securing element (16) is arranged axially between the spring material and at least one portion (8a, 8b, 8c, 9a, 9b, 9c), in particular bearing portion (8a, 9a), of the respective joint part (8, 9), preferably in that the securing element (16) is coupled axially, in particular on both sides, to the respective joint part (8, 9) in a form-fitting manner.

3. Drive according to either of the preceding claims, characterized in that the securing element (16) is configured to be flat, in particular disc-shaped, in the radial direction, and / or in that the securing element (16) has a radial outer contour which deviates from a round shape, and / or in that the securing element (16) has a substantially oval or round or polygonal radial outer contour, preferably in that the securing element (16) is secured against rotation on a mating element (18) which in particular is connected non-rotatably to the respective joint part (8, 9) or is furthermore formed integrally with the respective joint part (8, 9).

4. Drive according to one of the preceding claims, characterized in that the hollow cylinder (5), at its axial end facing the associated joint part (8), is provided with an axial extension (19) which is axially fixed with respect to the hollow cylinder (5), and in that, in the mounted state, the securing element (16) is screwed onto the axial extension (19), preferably in that the axial extension (19) has an axial end portion (20) with a cross section which is reduced in relation to the inside diameter of the securing element (16).

5. Drive according to Claim 4, characterized in that the axial extension (19) and / or the axial end portion (20) is in, in particular force-fitting, engagement with a corresponding receptacle (21) of the respectively associated joint part (8, 9).

6. Drive according to one of the preceding claims, characterized in that the hollow cylinder (5), in particular the axial extension (19), and / or the rod (5) has an external thread (23), in that the securing element (16) has a corresponding internal thread (24), and in that the external thread (23) together with the internal thread (24) in the mounted state forms the threaded connection, preferably in that, on the axial extension (19), a threaded portion (25) which forms the external thread (23) adjoins the axial end portion (20).

7. Drive according to one of the preceding claims, characterized in that the threaded connection is secured against loosening, and / or in that the hollow cylinder (6), in particular the axial extension (19), and / or the rod (5) has a securing against rotation portion (26), in particular a securing against rotation portion (26) which is arranged axially outside the threaded portion (25) and which is in, in particular force-fitting, engagement with a corresponding receptacle (27) of the respectively associated joint part (8, 9), preferably in that the axial end portion of the axial extension (19) forms the securing against rotation portion (26), and / or in that the engagement of the internal thread (24) with the external thread (23) is configured to be self-locking in the release direction.

8. Drive according to one of the preceding claims, characterized in that the drive (1) has a drive housing (28) with an inner and an outer housing tube (29, 30), which housing tubes run telescopically one into the other during an adjustment between the retracted position and the extended position, preferably in that the two housing tubes (29, 30) are axially fixed with respect to one respectively associated joint part of the joint parts (8, 9) .

9. Drive according to one of the preceding claims, characterized in that the drive spring assembly (14) is arranged radially between the drive unit (4) and the drive housing (28), preferably in that a spring guide tube (31) is arranged radially between the drive unit (4) and the drive spring assembly (14).

10. Drive according to Claim 8 or 9, characterized in that at least one of the housing tubes (29, 30), in particular the inner housing tube (29), has a centring collar (34) which runs radially within the housing tube (29, 30) in the axial direction along the respectively associated component (5, 6) of the drive unit (4), in particular the axial extension (19) or the rod (6), and preferably, as an installation aid, forms a receptacle (35), which widens radially in the axial direction, for the respectively associated component (5, 6) and / or centres the respective component (5, 6) with respect to the respectively associated joint part (8, 9), furthermore preferably in that the centring collar (34) is configured to provide a seal in the axial direction.

11. Drive according to one of the preceding claims, characterized in that at least one of the housing tubes (29, 30) has at least one drainage opening (36), preferably at least two drainage openings (36), furthermore preferably at least three drainage openings (36), even furthermore preferably at least four drainage openings (36), said drainage openings fluidically connecting an internal space of the drive (1) to the surroundings, preferably in that the centring collar (34) has at least one drainage opening (37), and in that the drainage opening (36) of the joint part is fluidically in contact with the drainage opening (37) of the centring collar.

12. Drive according to one of the preceding claims, characterized in that the securing element (16) and / or the at least one drive spring (15) of the drive spring assembly (14) and / or the respective component (5, 6) of the drive unit (4) and / or the axial extension (19) are / is made from metal, and / or in that the respective joint part (8, 9) and / or the respective housing tube (29, 30) are / is made from a plastics material.

13. Drive according to one of the preceding claims, characterized in that the drive unit (4) is configured as a gas pressure spring (38), wherein the first component (5) is a gas-filled gas pressure spring cylinder (39) and the second component (6) is a gas pressure spring piston rod (40) guided axially therein, or in that the drive unit (4) is configured as a spindle drive unit, wherein the first component (5) is a spindle nut tube with a spindle nut axially fixed and rotationally fixed with respect thereto, and the second component (6) is a threaded spindle meshing with the spindle nut.

14. Method for installing a drive according to one of the preceding claims, characterized in that the inner housing tube (29) is connected to the associated joint part (9), to the drive unit (4) and to the spring assembly (14), preferably by the inner housing tube (29) being pushed over one of the components (5, 6) of the drive unit (4), in particular the rod (6), and the drive spring (15), and, in the process, being centred via the centring collar (34) with respect to the component (6) of the drive unit (4).

15. Method according to Claim 14, characterized in that subsequently the securing element (16) is introduced into the other joint part (8), in that subsequently the joint part (8) is screwed via the securing element (16) to the associated component (5) of the drive unit (4), in particular to the axial extension (19), in order to form the threaded connection, preferably in that subsequently the outer housing tube (30) is pushed over the joint part (8) and latches to the latter.