WO2020148357A2

WO2020148357A2 - Spindle drive for an adjusting element of a motor vehicle

Info

Publication number: WO2020148357A2
Application number: PCT/EP2020/050957
Authority: WO
Inventors: Marco Schramm; Franziska Eßel; Matthias Fischer
Original assignee: Brose Fahrzeugteile Se & Co. Kommanditgesellschaft, Bamberg
Priority date: 2019-01-16
Filing date: 2020-01-16
Publication date: 2020-07-23
Also published as: WO2020148357A3; DE102019101065A1

Abstract

The invention relates to a spindle drive for an adjusting element (2) of a motor vehicle, wherein: a tubular drive housing (5) is provided, having a housing inner tube (5a) and a housing outer tube (5b), which telescope inside one another on adjustment of the spindle drive (1) between an extended position and a retracted position; a spindle/spindle nut transmission (7) is provided in the drive housing (5), having a spindle (8) and a spindle nut (9) in meshing engagement therewith for generating linear drive movements along the geometrical spindle axis (4) of the spindle (8); a first drive connection (10) and a second drive connection (11) are provided to output the drive movements; a sealing cap (15) is provided, which seals the drive housing (5) in the region of the first drive connection (10) and which is penetrated by a drive-train component (13) of the spindle drive (1), which comprises the first drive connection (10); the sealing cap (15) is connected in an axially fixed manner to the housing inner tube (5a); an annular space (16) is formed between the radially outer face of the housing inner tube (5a) and the radially inner face of the sealing cap (15), into which annular space the housing outer tube (5b) is axially plunged on an adjustment of the spindle drive (1) from the extended position into the retracted position. According to the invention, the sealing cap (15) has at least one drain cut-out (17, 18, 19) arranged offset and/or at a radial distance from the geometrical spindle axis (4).

Description

Spindle drive for an adjusting element of a motor vehicle

The invention relates to a spindle drive for an adjusting element of a motor vehicle according to the preamble of claim 1 and a spindle drive for an adjusting element of a motor vehicle according to the preamble of claim 16.

The spindle drive in question can be used for all types of adjusting elements of a motor vehicle. Exemplary adjustment elements are tailgates, trunk lids, side doors, bonnets or the like.

Particularly when the spindle drive is used in the wet area, for example in an area located to the side of a tailgate opening, there are particularly high demands on the spindle drive with a view to preventing moisture from entering the drive housing.

The known spindle drive (DE 10 2016 120 178 A1), from which the invention is based, shows a tubular, two-part drive housing with two housing sections in the form of a housing inner tube and a housing outer tube running telescopically therein. The drive housing is closed in the area of a drive connection by a housing cover which is penetrated by a drive train component of the spindle drive, which comprises an assigned drive connection. As an additional sealing measure, a sealing cap is provided which is placed on the drive housing in the area of this drive connection and which is likewise penetrated by the drive train component.

While the known spindle drive generally provides a good seal of the drive housing, a certain position of the spindle drive can result in moisture between the sealing cap and the drive housing via a gap between the radial outside of the housing inner tube and the radial inside of the sealing cap into the interior of the sealing cap arrives in an annular space between the inner tube and sealing cap. If the spindle drive is then adjusted to its retracted position, the outer housing tube moves telescopically along the inner tube and plunges into the annular space between the inner tube and Sealing cap, so that the moisture in this annulus cannot escape. Under certain circumstances, the liquid in this annular space is compressed so much when the outer housing tube is immersed that a part gets between the inner tube and the outer tube. A challenge is therefore to keep the area between the inner tube and the sealing cap as free as possible from moisture, in order to avoid, among other things, that the moisture freezes in the cold and this can lead to a system failure or damage to the drive. The invention is based on the problem of designing and developing the known spindle drive in such a way that the sealing of the drive housing is improved.

The above problem is solved in a spindle drive according to the preamble of claim 1 by the features of the characterizing part of claim 1.

The fundamental consideration is to design the sealing cap in such a way that any moisture or liquid that may accumulate in it can run off as optimally as possible. The drainage of accumulated liquid is improved at least for a position of the spindle drive in which the housing outer tube is not yet or at least not completely immersed in the sealing cap when the spindle drive is adjusted in the direction of its retracted position. However, it is particularly preferably possible to run off even when the housing outer tube is in its end position in the retracted position of the spindle drive. The drainage of liquid is, as proposed, achieved by drainage cutouts. A drainage recess is generally a recess in the sealing cap through which liquid can flow outwards from the inside of the sealing cap. In this case, such a recess can be a recess on the edge or an axial recess on the edge, that is to say a recess that is not completely enclosed by the material of the sealing cap. However, a recess can also be formed by an opening or a hole, that is to say by a recess which is completely surrounded by the material of the sealing cap. Specifically, it is proposed that the sealing cap have at least one drain recess radially spaced and / or offset from the geometric spindle axis. In particular, the respective drain recess is radially spaced and / or offset from a drive connection opening which is coaxial with the geometric spindle axis and through which the drive train component, which axially penetrates the sealing cap, is passed from the inside of the cap to the outside.

In the particularly preferred embodiment according to claim 2, at least one drain recess is an edge recess on the axial edge of the sealing cap facing the second drive connection. The sealing cap has in particular a cover section and a sleeve section, the axial edge of the sealing cap then being the axial edge of the sealing cap facing away from the cover section. Additionally or alternatively, at least one drain recess is provided, which is designed as an opening in the sealing cap, that is to say as a hole completely surrounded by material.

According to the further preferred embodiment according to claim 3, a plurality of drainage cutouts can also be arranged in the circumferential direction, in particular at uniform angular intervals over the circumference, in order to cover all positions / outlet directions in the case of a variable installation position.

Claims 4 to 7 define preferred configurations in which at least one drainage recess is designed as an edge-side recess. One or more such drain recesses on the edge form an uneven course of the end of the sealing cap facing the second drive connection. In particular, a circumferential, crown-like contour can be created here, that is to say a contour which is distinguished by projecting and recessed sections which alternate in each case. Such an uneven contour has the advantage that liquid can adhere less well to the radial inner side of the sealing cap when the axial edge of the sealing cap facing the second drive connection at least essentially points in the direction of gravity than in the case of a uniform circumferential axial edge of the sealing cap. An uneven contour reduces the adhesive force, which means that water cannot flow off a surface in the direction of gravity. Claim 8 defines a particularly preferred construction of the sealing cap with a sleeve section and a cover section. The cover section faces the first drive connection and the sleeve section extends axially from the cover section in the direction of the second drive connection. The cover section preferably has a drive connection opening which is coaxial with the geometric spindle axis and through which the drive train component, which comprises the first drive connection, is guided. The one or more drain recesses provided according to the proposal are then preferably radially spaced from the drive connection opening.

Claims 9 to 12 relate to preferred configurations in which at least one drain recess is formed by an opening in the sealing cap. At least one opening in the sleeve section and / or at least one opening in the cover section can be provided. The at least one opening forming an outlet recess opens particularly preferably into an outlet channel which is formed by a sealing cap projection. A sealing cap projection is a projection which, in addition, protrudes radially or axially with respect to the sealing cap. To this extent, it can be a radial sealing cap projection or an axial sealing cap projection. The sealing cap projection is shaped in such a way that it connects the respective opening forming a drainage recess in the cover section or in the sleeve section with the surroundings. The respective outlet channel extends from the corresponding opening in the cover section or sleeve section to a corresponding channel outlet. In principle, however, it is also conceivable to provide only the respective opening forming a drain recess, in particular in the sleeve section, and to dispense with an additional sealing cap projection with a drain channel. The opening then particularly preferably has an opening wall with two mutually opposite wall sections which, in a cross section along a plane in which the spindle axis lies, run at an angle to the spindle axis and in this respect form an oblique channel within the wall forming the sleeve section. This channel particularly preferably has a course starting from the radial inside to the radial outside of the sleeve section, which has a directional component from the first drive connection in the direction of the second drive has connection. The radially inside channel entrance is therefore axially closer to the cover section than the radially outside channel exit.

In the further preferred embodiment according to claim 13, a drive motor is provided in the drive housing, to which the spindle-spindle nut transmission is connected in terms of drive technology. In principle, the spindle drive can also be designed without a motor.

Claim 14 defines a particularly preferred embodiment, in which a guide tube is connected axially fixed to the first drive connection and, together with the first drive connection, forms said drive train component which penetrates the sealing cap. The drive train component is axially fixed to the spindle nut. Accordingly, the sealing cap provided according to the proposal is a sealing cap provided on the spindle nut side or on the output side. In principle, however, the case is also conceivable in which the sealing cap forms a spindle-side or drive-side sealing cap. In this case, the spindle or the drive motor is axially fixed to the first drive connection and, together with the first drive connection, forms said drive train component.

In the further preferred embodiment according to claim 15, a seal of the drive housing is provided in the area of the first drive connection. The seal can be achieved via an at least sectionally elastic sealing cap, which rests sealingly on the drive train component.

According to a further teaching according to claim 16, which is of independent importance, a spindle drive for an adjusting element of a motor vehicle is claimed, wherein a tubular drive housing with a housing inner tube and a housing outer tube, which when the spindle drive is adjusted between an extended position and a retracted position running telescopically into one another is provided, wherein in the drive housing a spindle-spindle nut gear is provided with a spindle and a spindle nut in meshing engagement with it for generating linear drive movements along the geometrical spindle axis of the spindle, with a first drive input for deriving the drive movements. End and a second drive connection are provided, wherein a sealing cap is provided, which closes the drive housing in the area of the first drive connection or in the area of the second drive connection and which is penetrated by a drive train component of the spindle drive, which comprises the drive connection, the sealing cap with the Housing inner or outer tube is axially connected. It is essential that the sealing cap has at least one joining surface via which it is integrally connected to the inner or outer tube of the housing by means of laser welding, in particular laser transmission welding, also called laser transmission welding. In this regard, reference may be made to all explanations regarding the proposed spindle drive according to the first teaching.

Claim 17 relates to a preferred embodiment in which the sealing cap is laser-transparent, that is to say transparent to the laser beam, as a result of which the latter can penetrate the material of the sealing cap during laser transmission welding and, at the joint, the material of the laser-absorbing inner or outer tube and by the heat generated in particular the material of the sealing cap can also melt locally at the joint. The integral connection is formed by cooling the melt.

Claim 18 relates to a preferred embodiment, in which the sealing cap connected to the housing inner or outer tube by means of laser welding, in particular laser transmission welding, has a drainage recess or is free of drainage recesses.

The invention is explained in more detail below on the basis of a drawing which merely shows exemplary embodiments. In the drawing shows

1 shows the rear area of a motor vehicle with a proposed spindle drive,

2 shows a first embodiment of the proposed spindle drive with the sealing cap provided in the area of the first drive connection a) in an almost extended position, b) in an intermediate position and c) in an almost retracted position, 3 shows a further exemplary embodiment of a proposed spindle drive with a sealing cap provided in the area of the first drive connection a) in a perspective view in an almost extended position of the spindle drive, b) in a sectional view in the almost extended position of the spindle drive and c) in a sectional view in an almost retracted position of the spindle drive,

4 shows yet another exemplary embodiment of a proposed spindle drive with a sealing cap provided in the area of the first drive connection a) in a perspective view in an almost extended position of the spindle drive, b) in a sectional view in the almost extended position of the spindle drive and c) in a sectional view in an almost retracted position of the spindle drive,

5 shows the rear area of a motor vehicle with a proposed spindle drive according to yet another exemplary embodiment, FIG. 6 variants of a sealing cap for the spindle drive according to FIG. 5, which closes the drive housing in the area of the first drive connection, shown in the assembled state, and

7 shows a variant of a sealing cap for the spindle drive according to FIG. 5, which closes the drive housing in the region of the second drive connection, shown in the assembled state.

The spindle drive 1 shown in the drawing is assigned to an adjusting element 2 of a motor vehicle, which here and preferably is a tailgate 3. In the present case, all statements relating to a tailgate 3 apply to all other types of adjustment elements 2 of a motor vehicle. In this respect, reference may be made to the exemplary list in the introductory part of the description. The spindle drive 1 is used for motorized adjustment of the tailgate 3. For this purpose, the spindle drive 1 is on the motor vehicle body on the one hand and on the Tailgate 3, on the other hand, articulated at a distance from a pivot axis 3a of the tailgate 3. The spindle drive 1 generates linear drive movements along the geometric spindle axis 4, so that the tailgate 3 can be adjusted by a motor between a closed position and the open position shown in FIG. 1.

1 shows that the spindle drive 1 has a tubular drive housing 5 with two housing sections 5a, 5b. Here and preferably, a housing inner tube 5a and a housing outer tube 5b are provided as housing sections, which telescopically run into one another when the spindle drive 1 is adjusted between an extended position and a retracted position.

Here and preferably, in the drive housing 5 along the spindle axis 4, a drive motor 6 and a spindle-spindle nut transmission 7 connected downstream of the drive motor 6 are provided one behind the other. An intermediate gear can optionally be provided between the drive motor 6 and the spindle-spindle nut gear 7. The drive motor 6 drives the spindle 8 of the spindle-spindle nut transmission 7, so that the spindle nut 9 of the spindle-spindle nut transmission 7, which is non-rotatably but axially movable in the spindle drive 1, performs an axial movement.

A first drive connection 10 and a second drive connection 11 are provided for diverting the drive movements and are arranged here and preferably on the spindle axis 4.

A guide tube 12 is connected to the first drive connection 10 and, together with the first drive connection 10, forms a combined drive train component 13. Here and preferably, the drive connection 10 is equipped with a ball socket and with an extension 10b adjoining the ball socket. Instead of the ball socket, the first drive connection 10 can also be designed with a ball head or another connection element. The extension 10b is axially fixed and non-rotatably connected to the guide tube 12. At its end facing away from the first drive connection 10, the guide tube 12 is axially fixed and non-rotatably connected to the spindle nut 9 of the spindle-spindle nut transmission 7, so that the axial movements of the spindle nut 9 are passed on to the first drive connection 10 via the guide tube 12.

The second drive connection 1 1 is arranged on the motor side of the spindle drive 1, so that a motorized adjustment of the spindle nut 9 produces an adjustment of the drive connections 10, 1 1 relative to one another along the spindle axis 4.

The figures also show that the spindle drive 1 can also have a housing cover 14 which closes the drive housing 5 in the region of the first drive connection 10 and which is penetrated by the drive train component 13.

Furthermore, a sealing cap 15 is provided, which closes the drive housing 5 in the region of the first drive connection 10 and which is penetrated by the drive train component 13 of the spindle drive 1, which comprises the first drive connection 10. The sealing cap 15 is axially fixed to the housing inner tube 5a, an annular space 16 being formed between the radial outside of the housing inner tube 5a and the radial inside of the sealing cap 15, into which the housing outer tube 5b is moved when the spindle drive 1 is moved from the extended position into axially immerses the retracted position.

For the sake of completeness, it should be pointed out that here the guide tube 12 is connected axially fixed to the first drive connection 10 and, together with the first drive connection 10, forms the drive train component 13 which penetrates the sealing cap 15, the drive train component 13 with the spindle nut 9 of the spindle Spindle nut gear 7 is axially connected. Alternatively, it can also be provided in an exemplary embodiment (not shown here) that the spindle 8 or the drive motor 6 is axially fixed to the first drive connection 10 and, together with the first drive connection 10, forms the drive train component 13 which penetrates the sealing cap 15.

Up to this point, the structure of the proposed spindle drive 1 corresponds to the structure of the spindle drive shown in DE 10 2016 120 178 A1 goes back to the applicant and the content thereof is made the subject of the present application.

It is essential for the proposed solution that the sealing cap 15 has at least one drain recess 17, 18, 19 which is radially spaced and / or offset from the geometric spindle axis 4. A drainage recess is generally a recess through which moisture or liquid accumulated in the sealing cap 15 can flow out of the interior of the cap. In this way, moisture inside the cap is minimized compared to a completely closed sealing cap. Accordingly, it is prevented that, when the spindle drive 1 is retracted from its extended position into its retracted position, liquid gets between the inner tube 5a and the outer tube 5b. The risk of freezing in the case of minus degrees in the retracted position of the spindle drive 1 is also minimized.

2 on the one hand and FIGS. 3 and 4 on the other hand differ in the design of the drainage recess 17, 18, 19. In the case of FIG. 2, there are several edge-side recesses 17 on the second drive connection 1 1 facing axial edge 15a of the sealing cap 15 provided. 3 and 4, on the other hand, show an embodiment in which a plurality of drain recesses 18, 19 in the form of an opening, that is to say a hole, are provided in the sealing cap 15. In principle, only one such drain recess 17, 18, 19 can be provided, or several such drain recesses 17, 18, 19 can be provided. In principle, one or more cutouts 17 on the edge can also be combined with one or more openings 18, 19 forming a runout cutout. If a plurality of drainage cutouts 17, 18, 19 are provided, these are arranged, in particular distributed uniformly, in particular in the circumferential direction around the geometric spindle axis 4.

The exemplary embodiment according to FIG. 2 will first be discussed below. Here, a plurality of marginal recesses 17 are provided, which are arranged at regular angular intervals in the circumferential direction. The respective edge-side recess 17 has two recess side edges 17a, each axially with the one forming the axial edge 15a outer edge of the sealing cap 15 each meet in a corner 20, here an outer corner. Additionally or alternatively, it can also be provided that the respective drain recess 17 has a corner 20 in the form of an inner corner, which is formed at a point at which a recess base edge 17b, i.e. the deepest edge of the drain recess 17, meets the respective recess side edge 17a. By providing corners 20 here and preferably no curves, the adhesive force that holds the liquid on the inside of the sealing cap 15 is markedly reduced. In this way, as shown in FIG. 2b), liquid can flow off particularly easily if the spindle drive 1 is moved in the direction of its retracted position and the sealing cap is arranged such that its axial edge 15a facing the second drive connection 11 is at least partially in Direction of gravity.

The edge-side recesses 17 have the additional advantage that, at the beginning of the immersion of the outer housing tube 5b into the annular space 16, liquid is first forced out of the annular space 16 through the recesses 17 before the recesses 17 are covered or closed on the inside by the outer housing tube 5b .

The cutout side edges 17a run here and preferably parallel to the geometric spindle axis 4. The cutout base edge 17b runs here in a plane orthogonal to the geometric spindle axis 4. A circumferential, crown-like contour with essentially rectangular projections and depressions is thereby formed. However, other configurations of the radial cutouts 17 are also conceivable, for example those in which the two cutout side edges 17a of a cutout 17 meet directly and form an inner corner between them, in which case no cutout base edge is provided. Additionally or alternatively, configurations of the radial recesses 17 are also conceivable, in which a recess side 17a of a recess 17 and a recess side edge 17a of the respectively adjacent recess 17 meet directly and form an outer corner.

A preferably irregular contour, preferably with corners 20, is thus preferably created in the region of the axial edge 15a of the sealing cap 15, as a result of which the drainage of liquid is facilitated due to reduced adhesive forces.

Here and preferably, the outer housing tube 5b is in the retracted state of the spindle drive 1 with the edge-side recess 17 in at least partial, here complete, radial overlap.

Here, and preferably, it is further provided that the axial edge 21 of the outer housing tube 5b, which faces the first drive connection 10, has a circumferential chamfer 21a, which is here and preferably directed radially outward. Such a chamfer 21 a improves the displacement of liquid radially outwards at the beginning of the immersion of the housing outer tube 5 b in the annular space 16.

A further exemplary embodiment is now explained below with reference to FIG. 3. Here and preferably one or more openings forming a drain recess 18, that is to say holes surrounded by the material of the sealing cap 15, are provided in the sealing cap 15, specifically in a sleeve section 15b and / or in a cover section 15c of the sealing cap 15. In the illustration according to FIG 3 only one such opening 18 is shown, but such an opening 18 can also be provided at one or more other locations.

As can be seen in FIG. 3b), the cover section 15c here and preferably has a drive connection opening 22 coaxial with the geometric spindle axis 4, through which the drive train component 13, which axially penetrates the sealing cap 15, is passed axially. For sealing between the drive connection opening 22 and the drive train component 13 passed through it, the sealing cap 15 is here elastic, and preferably at least in sections, and is sealingly in contact with the drive train component 13.

The at least one, here exactly the one, drain recess or opening 18 is here and preferably radially spaced from the drive connection opening 22. The only drain recess or opening 18 here, as shown here, is particularly preferably at one in the extended and / or retracted ren position of the spindle drive 1 in the direction of gravity or the bottom of the spindle drive 1, which has the advantage that no rain water can penetrate through this opening 18 from the outside into the sealing cap 15.

In the embodiment according to FIG. 3 it is further provided that the at least one opening 18 opens into a drain channel 23 which is formed by a radial sealing cap projection 24, that is to say a section of the sealing cap 15 projecting in the radial direction relative to the sleeve section 15b. The drain channel 23 extends outside the sealing cap wall forming the sleeve section 15b. The sealing cap projection 24 is arranged here and preferably on the sleeve section 15b. The drain channel 23 runs here and preferably at least in sections, in particular in an end section, axially in the direction of the second drive connection to a channel outlet, in particular to an axial channel outlet.

As illustrated in FIG. 3b, when the spindle drive 1 is in its extended position, liquid that flows into the sealing cap 15 can flow out of it again directly via the outlet channel 23 and does not accumulate there, at least not to any significant degree.

It is further here and preferably so that the annular space 16 extends from the side of the sealing cap 15 facing the second drive connection 11 to the cover section 15c and extends axially past the opening 18. If, when the spindle drive 1 is moved into its retracted position, the outer housing tube 5b is immersed in the annular space 16, any liquid is axially displaced from the outer housing tube 5b in the direction of the cover section 15c, as a result of which the liquid reaches the area of the opening 18 and there via the outlet channel 23 can flow out of the sealing cap 15.

Additionally or alternatively, what is not shown here, at least one opening forming an outlet recess 18 can open into an outlet channel which is formed by an axial sealing cap projection, that is to say an axially projecting section of the sealing cap 15 from the cover section 15c. This sealing cap projection can thus be arranged on the cover section 15c and axially, in particular axially, in relation to the latter ß, protrude, the drain channel then preferably at least in sections, in particular in an end section, extends radially outward to a channel outlet, in particular to a radial channel outlet.

A further exemplary embodiment is explained below with reference to FIG. 4. Here and preferably, as in FIG. 3, one or more openings forming a drain recess 19, that is to say holes surrounded by the material of the sealing cap 15, are provided in the sleeve section 15b and / or in a cover section 15c of the sealing cap 15. Several such openings 19 are provided here by way of example, but only one such opening 19 can also be provided here.

Here and preferably, the at least one opening 19 has an opening wall formed by the material of the sleeve section 15b. In this exemplary embodiment there is preferably no sealing cap projection with an outlet channel running outside the sealing cap wall forming the sleeve section 15b, but the opening 19 is designed such that it forms a channel within the sealing cap wall forming the sleeve section 15b.

Preferably, the opening wall, as shown in Fig. 4c, two opposite wall sections 19a, 19b, which are angular to the geometric spindle axis 4 in a cross section along a plane in which the geometric spindle axis 4 lies. The wall sections 19a, 19b run here and preferably starting from the radial inside of the sleeve section 15b to the radial outside of the sleeve section 15b in a direction which has a directional component from the first drive connection 10 in the direction of the second drive connection 11. The wall sections 19a, 19b thus form a channel which extends radially from the inside through the material of the sleeve section 15b and which has an angular course with respect to the geometric spindle axis 4 with a directional component from the first drive connection 10 in the direction of the second drive connection 11. Liquid runs out of the sealing cap 15 obliquely downwards. As illustrated in FIG. 4b, in this embodiment as well, when the spindle drive 1 is in its extended position, liquid that flows into the sealing cap 15 can flow out of the latter again directly via the opening 19.

Furthermore, it is here and preferably so that the annular space 16 only extends from the side of the sealing cap 15 facing the second drive connection 11 to approximately the axial height of the opening 19. In the further axial course, the sleeve section 15b then and preferably has a greater wall thickness here, the sealing cap wall extending radially inwards almost to the inner tube 5a or preferably even to the inner tube 5a. A constriction is thus formed here between the inside of the sleeve section 15b and the outside of the housing inner tube 5a. If, when the spindle drive 1 is moved into its retracted position, the outer housing tube 5b is immersed in the annular space 16, any liquid is displaced axially from the outer housing tube 5b out of the annular space 16 axially past the constriction in the direction of the cover section 15c, as a result of which the liquid enters the area of the opening 19 arrives and can flow out of the sealing cap 15 there.

According to a further teaching, which is of independent importance, a spindle drive 1 for an adjusting element 2 of a motor vehicle is claimed, a tubular drive housing 5 having a housing inner tube 5a and a housing outer tube 5b, which, when the spindle drive 1 is adjusted, moves between an extended position and one retracted position telescoping into each other, is provided, wherein in the drive housing 5, a spindle-spindle nut gear 7 with a spindle 8 and a meshing engagement with the spindle nut 9 is provided for generating linear drive movements along the geometric spindle axis 4 of the spindle 8, whereby for rejection of the drive movements, a first drive connection 10 and a second drive connection 11 are provided, a sealing cap 15 being provided which closes the drive housing 5 in the area of the first drive connection 10 or in the area of the second drive connection 11 and the is penetrated by a drive train component 13 of the spindle drive 1, which comprises the drive connection 10, 1 1, the sealing cap 15 being connected axially fixed to the inner or outer tube 5a, 5b. It is essential here that the sealing cap 15 has at least one joining surface 25, by means of which it is integrally connected to the inner or outer tube 5a, 5b by means of laser welding, in particular laser transmission welding. Reference may be made to the above statements regarding the proposed spindle drive 1 according to the first teaching.

Such an axial fixation is for a sealing cap 15 (FIGS. 5, 6) closing the drive housing 5 in the area of the first drive connection 10 and / or for a sealing cap 15 closing the drive housing 5 in the area of the second drive connection 11 (FIGS. 5, 7 ) conceivable.

Here, and preferably, it is provided that the sealing cap 15 penetrates into the sealing cap 15 at least in the, in particular radial, material section between the at least one joining surface 25 and the respective entry point 26, at which the laser beam 27 producing the cohesive connection during the assembly during laser transmission welding , is laser transparent. Here and preferably the entry point 26 is radially opposite the joining surface 25.

Optionally, not necessarily as in the first teaching, the sealing cap 15, as shown in FIGS. 6c) to e) for a sealing cap 15 closing the drive housing 5 in the area of the first drive connection 10, can be at least one radially spaced from the geometric spindle axis 4 and / or have staggered drain recesses 17, 18, 19. In this case, the at least one drain recess 17, 18, 19 can be spaced apart from the joining surface 25, as shown here, or can be arranged adjacent to the joining surface 25.

The drainage cutouts shown here are designed, for example, as openings 18 in the sleeve section 15b of the sealing cap 15. With regard to further configurations, reference may be made to the explanations for the first teaching.

Alternatively, however, it is also conceivable that the sealing cap 15 is free of drainage cutouts, as is shown in FIGS. 6a) and b) for a sealing cap 15 and in which seals the drive housing 5 in the region of the first drive connection 10 7 for a sealing cap 15 closing the drive housing 5 in the area of the second drive connection 11.

To axially fix the sealing cap 15 relative to the associated drive train component 13, the sealing cap 15 can, as shown in the enlarged detail in FIG. 6a), be locked with an element axially fixed to the associated drive connection 10, 11. It is also conceivable for the sealing cap 15 to be elastic at least in sections and to be sealingly in contact with the drive train component 13 and / or the associated drive connection 10, 11, as shown in FIGS. 6b) to e).

Claims

1. Spindle drive for an adjusting element (2) of a motor vehicle, a tubular drive housing (5) with a housing inner tube (5a) and a housing outer tube (5b) which telescopically when the spindle drive (1) is adjusted between an extended position and a retracted position run into each other, is provided, wherein in the drive housing (5) a spindle-spindle nut gear (7) with a spindle (8) and a meshing engagement with the spindle nut (9) for generating linear drive movements along the geometric spindle axis (4) of the spindle (8) is provided, with a first drive connection (10) and a second drive connection (11) being provided for diverting the drive movements, a sealing cap (15) being provided, which seals the drive housing (5) in the region of the first drive connection (10) closes and that of a drive train component (13) of the spindle drive (1) which connects the first drive connection (10) is penetrated, the sealing cap (15) being axially fixed to the housing inner tube (5a), an annular space (16) being formed between the radial outside of the housing inner tube (5a) and the radial inside of the sealing cap (15) the housing outer tube (5b) is immersed axially when the spindle drive (1) is adjusted from the extended position to the retracted position,

characterized,

that the sealing cap (15) has at least one drain recess (17, 18, 19) that is radially spaced and / or offset from the geometric spindle axis (4).

2. Spindle drive according to claim 1, characterized in that at least one drain recess (17) is an edge-side recess (17) on the second drive connection (11) facing axial edge (15a) of the sealing cap (15), and / or that at least one Drain recess (18, 19) is an opening (18, 19) in the sealing cap (15).

3. Spindle drive according to claim 1 or 2, characterized in that a plurality of drain recesses (17, 18, 19) are provided in the circumferential direction, in particular evenly distributed over the circumference.

4. Spindle drive according to one of the preceding claims, characterized in that the respective edge-side recess (17) has recess side edges (17a) and that at least one recess side edge (17a), preferably both recess side edges (17a), each with an axially outer edge (15a) the sealing cap (15) facing the second drive connection (11) meet in a corner (20), and / or that the respective edge-side recess (17) has recess side edges (17a) and that at least one recess side edge (17a ), preferably both recess side edges (17a), each with a recess base edge (17b) of the recess (17) facing the second drive connection (11) meet in a corner (20).

5. Spindle drive according to one of the preceding claims, characterized in that at least one recess side edge (17a), preferably both recess side edges (17a), run parallel to the geometric spindle axis (4), and / or that the recess base edge (17b) in one Geometric spindle axis (4) runs orthogonal plane.

6. Spindle drive according to one of the preceding claims, characterized in that the housing outer tube (5b) is in the retracted position with the edge recess (17) in at least sections, preferably in complete, radial overlap.

7. Spindle drive according to one of the preceding claims, characterized in that the axial edge (21) of the housing outer tube (5b), which faces the first drive connection (10), has a circumferential chamfer (21a), which is preferably directed radially outwards .

8. Spindle drive according to one of the preceding claims, characterized in that the sealing cap (15) has a sleeve section (15b) and a cover section (15c), preferably that the cover section (15c) has a drive connection opening (22) which is coaxial with the geometric spindle axis (4) ), through which the drive train component (13) which penetrates the sealing cap (15) is passed, further preferably that the at least one drain recess (17, 18, 19) is radially spaced from the drive connection opening (22).

9. Spindle drive according to one of the preceding claims, characterized in that at least one opening forming an outlet recess (18, 19) in the sleeve section (15b) and / or at least one opening forming an outlet recess (18, 19) in the cover section (15c) is trained.

10. A spindle drive according to claim 9, characterized in that at least one opening forming an outlet recess (18) opens into an outlet channel (23) which is formed by a radial sealing cap projection (24) which is arranged on the sleeve section (15b) and opposite it radially, in particular radially outwards, preferably that the outlet channel (23) at least in sections, in particular in an end section, axially in the direction of the second drive connection (11) to a channel outlet (23a), in particular to an axial channel outlet (23a), runs.

11. Spindle drive according to claim 9 or 10, characterized in that at least one opening forming an outlet recess (18) opens into an outlet channel which is formed by an axial sealing cap projection which is arranged on the cover section (15c) and axially, in particular axially, relative thereto protrudes to the outside, preferably that the drainage channel extends at least in sections, in particular in an end section, radially outward to a channel outlet, in particular to a radial channel outlet.

12. Spindle drive according to one of claims 9 to 11, characterized in that at least one opening forming a drainage recess (19) has an opening wall formed by the material of the sleeve section (15b), preferably in that the opening wall has two mutually opposite wall sections (19a, 19b ) which, in a cross section along a plane in which the geometric spindle axis (4) lies, run at an angle to the geometric spindle axis (4), further preferably that the wall sections (19a, 19b) starting from the radial inside of the sleeve section (15b ) to the radial outside of the sleeve section (15b) in a direction which has a directional component from the first drive connection (10) in the direction of the second drive connection (11).

13. Spindle drive according to one of the preceding claims, characterized in that in the drive housing (5) a drive motor (6) is provided, which is the spindle spindle gear (7) connected in terms of drive technology, wherein the drive housing (5) and the spindle nut gear (7) are arranged one behind the other in the drive housing (5) along the spindle axis (4), preferably that the spindle (8) is coupled in terms of drive technology to the drive motor (6), optionally via an intermediate gear.

14. Spindle drive according to one of the preceding claims, characterized in that a guide tube (12) with the first drive connection (10) is axially fixed and together with the first drive connection (10) the drive train component (13) which the sealing cap (15) penetrates, forms, wherein the drive train component (13) with the spindle nut (9) of the spindle-spindle nut gear (7) is axially fixed, or that the spindle (8) or the drive motor (6) with the first drive connection (10) axially fixed and together with the first drive connection (10) forms the drive train component (13) which penetrates the sealing cap (15).

15. Spindle drive according to one of the preceding claims, characterized in that for sealing between the drive connection opening (22) and the drive train component (13) passed therethrough, the sealing cap (15) is at least partially elastic and bears sealingly on the drive train component (13).

16. Spindle drive for an adjusting element (2) of a motor vehicle, in particular spindle drive according to one of the preceding claims, wherein a tubular drive housing (5) with a housing inner tube (5a) and a housing outer tube (5b) between an adjustment of the spindle drive (1) an extended position and a retracted position telescoping into each other is provided, wherein in the drive housing (5) a spindle spindle nut gear (7) with a spindle (8) and a spindle nut (9) in meshing engagement therewith for generating linear drive movements the geometric spindle axis (4) of the spindle (8) is provided, with a first drive connection (10) and a second drive connection (11) being provided for diverting the drive movements, a sealing cap (15) being provided, which seals the drive housing (5) in the region of the first drive connection (10) or in the area of the second drive connection (11) and which is penetrated by a drive train component (13) of the spindle drive (1), which comprises the drive connection (10, 11), the sealing cap (15) with the housing inner or outer tube (5a, 5b) is axially fixed,

characterized,

that the sealing cap (15) has at least one joining surface (25) by means of which it is integrally connected to the inner or outer tube (5a, 5b) by means of laser welding, in particular laser transmission welding.

17. Spindle drive according to claim 16, characterized in that the sealing cap (15) at least in the, in particular radial, material section between the at least one joining surface (25) and the respective entry point (26), on which during the assembly during laser transmission welding the Laser beam (27) which produces a materially bonded connection penetrates into the sealing cap (15), is laser-transparent, preferably that the entry point (26) is radially opposite the joining surface (25).

18. Spindle drive according to claim 16 or 17, characterized in that the sealing cap (15) has at least one drain recess (17, 18, 19) radially spaced and / or offset from the geometric spindle axis (4), preferably that at least one drain recess ( 17, 18, 19) is spaced from the joint surface (25) or is arranged adjacent to the joint surface (25), or that the sealing cap (15) is free of drainage cutouts (17, 18, 19).