SPINDLE GEAR, LENGTH ADJUSTER, VEHICLE SEAT

Abstract

Spindle gear (300; 400), in particular for a longitudinal adjuster (10), the spindle gear (300; 400) comprising: - a worm wheel (50a) mounted so as to be rotatable about an axis of rotation (A) and connectable to a spindle (20), - a drive worm (50b) connectable to a motor (60), by means of which the worm wheel (50a) can be driven, - a gear housing (52) enclosing the worm wheel (50a) and the drive worm (50b), wherein the worm wheel (50a) is positioned axially with respect to the axis of rotation (A) of the gear housing (52) without play, characterized in that ribs (310; 410) are arranged in the region of at least one contact surface (53d) between one of the housing halves (52a, 352b) and a bearing sleeve (56; 456), wherein at least one of the housing halves (52a, 352b) has the ribs (310) in the region of at least one contact surface (53d) for one of the bearing sleeves (56), and the ribs (310) cut at least partially into at least one of the bearing sleeves (56) when the two housing halves (52a, 352b) are plugged together, and as a result the worm wheel (50a) is positioned axially with respect to the axis of rotation (A) without play.

Description

[0001] The invention relates to a spindle gear, in particular for a longitudinal adjuster, the spindle gear comprising: - a worm wheel mounted so as to be rotatable about an axis of rotation, which can be connected to a spindle, - a drive worm that can be connected to a motor and by means of which the worm wheel can be driven, - a gear housing enclosing the worm wheel and the drive worm, wherein the worm wheel is positioned axially to the axis of rotation of the gear housing without play.

[0002] The invention further relates to a longitudinal adjuster, in particular for a vehicle seat, a vehicle seat. State of the art

[0003] DE 103 37 475 A1 discloses a longitudinal adjuster for adjusting an adjustment part in a motor vehicle, in particular a seat part, with a spindle gear. The spindle gear comprises a helical gear and a drive worm, each of which is mounted in bearings in a gear housing. Depending on the design of the bearings, both the helical gear and the drive worm can exhibit a certain amount of play relative to the gear housing. This play is caused by tolerances in the design of the gear housing and / or the helical gear or the drive worm and is detrimental to the operation of the spindle gear.If, in particular, the helical gear exhibits play in the longitudinal direction, which corresponds to the axial direction of a spindle that interacts with the helical gear during operation, this leads to inadequate support of the adjustment component to be adjusted by the spindle gear, for example, a vehicle seat. In this case, the seat is held by the spindle gear with play and can move relative to the spindle gear and thus to the adjustment mechanism during vehicle operation, particularly during a load reversal (braking, starting). This is unpleasant for the seat occupant and, secondly, leads to noise (rattling).

[0004] DE 10 2006 049 808 A1 discloses an adjusting gear for an adjusting device for adjusting an adjusting part in a motor vehicle, in particular a seat part. The adjusting gear comprises a gear housing and a helical gear arranged on a spindle of the adjusting device extending in a longitudinal direction and mounted on the gear housing for rotation about the longitudinal direction. The adjusting gear further comprises a drive worm rotatably mounted on the gear housing and interacting with the helical gear to drive the adjusting device. The adjusting gear has an additional means arranged on the gear housing in the form of a wedge-shaped projection, a bushing, or a spring washer, which acts between the gear housing and the helical gear and / or the drive worm to reduce the play between the gear housing and the helical gear and / or the drive worm.

[0005] DE 10 2008 029 152 A1 discloses a screw adjustment mechanism comprising a screw and a nut threaded onto the screw. The nut is rotatably mounted in a bearing that is elastically deformable and secured to a transverse wall of a housing. Task

[0006] The invention is based on the object of improving a spindle gear and a longitudinal adjuster of the type mentioned above, in particular of enabling a spindle gear with a lower tendency to develop disturbing noises, and of providing a corresponding longitudinal adjuster and vehicle seat. Solution

[0007] This object is achieved according to the invention by a spindle gear, in particular for a longitudinal adjuster, the spindle gear comprising: - a worm wheel mounted so as to be rotatable about an axis of rotation, which can be connected to a spindle, - a drive worm that can be connected to a motor and by means of which the worm wheel can be driven, - a gear housing enclosing the worm wheel and the drive worm, wherein the worm wheel is positioned axially free of play relative to the axis of rotation of the gear housing, wherein ribs are arranged in the region of at least one contact surface between one of the housing halves and a bearing sleeve.

[0008] Because the worm wheel is positioned axially to the axis of rotation of the gear housing without play and ribs are arranged in the area of ​​at least one contact surface between one of the housing halves and a bearing sleeve, abutment of the worm wheel in the axial direction against the gear housing is prevented, in particular when the direction of rotation is reversed, which leads to the formation of undesirable noises in the spindle gear.

[0009] Advantageous embodiments, which can be used individually or in combination with one another, are the subject of the subclaims.

[0010] The gear housing can be formed by several housing parts. The gear housing is preferably formed from two housing parts, in particular two housing halves. Furthermore, a gear holder can be provided, which encompasses the gear housing and by means of which the spindle gear is connected to the first rail. The spindle can be inserted through two mutually parallel legs of a substantially U-shaped gear holder. The two opposite legs are preferably connected to one another in a conventional manner via a web. Alternatively, the two legs can be without a web, i.e., without any connection to one another.

[0011] Each of the legs can be connected to a fastening leg, by means of which the gear holder is attached to the upper rail. Furthermore, the fastening legs are preferably bent or angled by approximately 90° relative to their respective legs. In the assembled state of the essentially U-shaped gear holder, the gear housing is preferably received between the legs in the longitudinal direction x. The fastening legs can have threaded holes, by means of which, in interaction with corresponding screws and / or threaded bolts, a connection to the first rail can be established.

[0012] The at least one surface section can be oriented longitudinally forward or rearward toward the gear holder, in particular a leg of the gear holder. The at least one surface section can be oriented vertically downward toward the gear holder, in particular a web of the gear holder. The at least one surface section can be oriented transversely to the left or right toward the first rail.

[0013] Parallel to a rotational axis of the worm gear, a step can be arranged on opposite outer sides of the gear housing. The gear housing can have a cylindrical bearing section adjacent to each step. The at least one step can protrude radially inward relative to the cylindrical bearing section. An inner diameter of the step can be smaller than an inner diameter of the cylindrical bearing section.

[0014] The gear housing can have a recess, preferably in an upper section of the cylindrical bearing portion. A worm gear screwed onto the spindle can be mounted in the gear housing by means of two bearing sleeves. The bearing sleeves can each have a collar. Each bearing sleeve can have a projection that interacts with the recess in the gear housing. The projection of the bearing sleeve in conjunction with the recess in the gear housing can provide an anti-rotation feature for the bearing sleeve. The bearing sleeves can be mounted in the gear housing in a rotationally secured manner.

[0015] The worm gear can be mounted in the gear housing by means of at least one bearing sleeve. The worm gear is preferably mounted in the gear housing by means of two bearing sleeves. The bearing sleeves can be arranged axially aligned with the rotational axis of the worm gear. The bearing sleeves can be arranged coaxially with the rotational axis of the worm gear.

[0016] The gear housing can have at least one cylindrical bearing section for supporting the worm gear. The gear housing can have a recess in the at least one cylindrical bearing section, and the at least one bearing sleeve can have a projection, wherein the projection of the bearing sleeve interacts with the recess of the gear housing.

[0017] The at least one bearing sleeve can have an end face, in particular a collar. A resilient means can be arranged between the end face or the collar of the at least one bearing sleeve and a respective adjacent contact surface of the gear housing, thereby positioning the worm gear axially free of play relative to the rotational axis. The resilient means can be a clamping washer or a disc spring.

[0018] At least one of the housing halves has rib-shaped means in the region of at least one contact surface for one of the bearing sleeves, which, particularly when the two housing halves are mated together, cut at least partially into at least one of the bearing sleeves, in particular a collar of at least one of the bearing sleeves, thereby positioning the worm gear axially free of play relative to the rotational axis. The rib-shaped means are preferably provided exclusively on one of the housing halves, whereas the cooperating housing half is free of rib-shaped means.

[0019] The at least one bearing sleeve can have a collar. The collar of the at least one bearing sleeve can have rib-shaped means on one half of a surface perpendicular to the axis of rotation, in the direction of the contact surface of the housing halves. These rib-shaped means support the respective bearing sleeve on the gear housing, particularly during mating of the two housing halves, such that the worm gear is positioned axially free of play relative to the axis of rotation.

[0020] The underlying object is further achieved according to the invention by a longitudinal adjuster, in particular for a vehicle seat, the longitudinal adjuster having at least one pair of rails which is formed from a first rail and a second rail which is displaceable in the longitudinal direction relative to the first rail, wherein the rails alternately engage around one another to form an inner channel, wherein a spindle mounted in the second rail is arranged in the inner channel, wherein a spindle gear which can be driven by means of a motor and interacts with the spindle is arranged in the first rail as described above.

[0021] The first rail is preferably a seat rail that can be connected to a vehicle seat. The second rail is preferably a floor rail that can be connected to a vehicle structure. A possible internal structure as well as the mode of operation and function of the spindle drive are known, for example, from DE 10 2013 207 665 A1, the relevant disclosure of which is hereby expressly incorporated by reference.

[0022] A spindle nut can be mounted on the second rail, which is operatively connected to the spindle.

[0023] The object is further achieved according to the invention by a vehicle seat with a previously described longitudinal adjuster. Figures and embodiments of the invention

[0024] Before describing embodiments of the invention in more detail below with reference to the figures, it should first be noted that the invention is not limited to the described components or the described method steps. Furthermore, the terminology used does not represent a limitation, but is merely exemplary. Where the singular is used in the description and claims below, the plural is also included unless the context explicitly excludes this.

[0025] The invention is explained in more detail below with reference to advantageous embodiments illustrated in the figures. However, the invention is not limited to these embodiments. They show: Fig. 1: a vehicle seat according to the invention, Fig. 2: a longitudinal adjuster according to the invention, Fig. 3: a side view of a pair of rails of the longitudinal adjuster of Fig. 2, with a first rail cut open in a first plane, Fig. 4: partial longitudinal section through the pair of rails of Fig. 3, in the area of ​​a spindle gear, Fig. 5: a perspective view of a first housing half of a gear housing of the spindle gear according to the prior art, Fig. 6: schematically the first half of the gearbox housing of Fig. 5 with inserted gearbox, Fig. 7: Partial perspective view of the first half of the gearbox housing with the gearbox inserted from Fig. 5, Fig. 8: schematically shows a spindle gear with the second housing half removed according to the first embodiment not according to the invention, Fig. 9: a perspective view of a bearing sleeve for use in a spindle gear according to a second embodiment not according to the invention, Fig. 10: a perspective view of a second housing half of a gear housing for use in a spindle gear according to a third embodiment, Fig. 11: a perspective view of a bearing sleeve for use in a spindle gear according to a fourth embodiment, Fig. 12: a partial schematic view of two housing halves with a bearing sleeve for use in a spindle gear according to a fifth embodiment not according to the invention, in a state during joining of the housing halves, and Fig. 13: the housing halves and the bearing sleeve of Fig. 12 in a state after joining the housing halves.

[0026] One in Fig. A vehicle seat 1 schematically illustrated in FIG. 1 is described below using three spatial directions running perpendicular to one another. In a vehicle seat 1 installed in the vehicle, a longitudinal direction x runs largely horizontally and preferably parallel to a vehicle longitudinal direction that corresponds to the normal direction of travel of the vehicle. A transverse direction y running perpendicular to the longitudinal direction x is also oriented horizontally in the vehicle and runs parallel to a vehicle transverse direction. A vertical direction z runs perpendicular to the longitudinal direction x and perpendicular to the transverse direction y. In a vehicle seat 1 installed in the vehicle, the vertical direction z runs parallel to the vehicle's vertical axis.

[0027] The position and direction specifications used, such as front, rear, top, and bottom, refer to the viewing direction of an occupant sitting in vehicle seat 1 in a normal seating position, with vehicle seat 1 installed in the vehicle, in a position suitable for passenger transport with the backrest 4 upright and oriented in the direction of travel as usual. However, vehicle seat 1 can also be installed in a different orientation, for example, transverse to the direction of travel.

[0028] In addition, the directional information used, such as axial, radial or circumferential, refers to cylindrical coordinates defined by means of a rotational axis A of a worm wheel 50a.

[0029] The Fig. The vehicle seat 1 for a motor vehicle shown in Figure 1 comprises a seat part 2 and a backrest 4 whose inclination is adjustable relative to the seat part 2. The inclination of the backrest 4 can be adjusted, for example, by means of a locking fitting or a geared fitting. The vehicle seat 1 is mounted on a longitudinal adjuster 10 for adjusting the seat's longitudinal position.

[0030] Fig. 2 shows, by way of example, a longitudinal adjuster 10 according to the invention for a vehicle seat 1. The longitudinal adjuster 10 has at least one pair of rails, in this case two pairs of rails. The pairs of rails are each formed from a first rail 12, in particular for connection to a seat structure of the vehicle seat 1, and a second rail 14, in particular for connection to a vehicle structure. The rails 12, 14 of the pair of rails are displaceable relative to one another in the longitudinal direction x and alternately engage around one another to form an inner channel 16. Arranged in the inner channel 16 are a spindle nut 30 fixedly connected to the second rail 14 and a spindle 20 operatively connected to the spindle nut 30. The spindle 20 extends along a spindle axis parallel to the longitudinal direction x. Arranged at a front end of the first rail 12 is a spindle gear 100; 200; 300; 400; 500, which can be driven by a motor 60.The spindle 20 is driven by means of the spindle gear 100; 200; 300; 400; 500. The motor 60 is held on a motor mount 70 mounted between the two spindle gears 100; 200; 300; 400; 500 of the respective rail pairs and drives by means of a . Fig. 2 not shown shaft the two spindle gears 100; 200; 300; 400; 500.

[0031] According to a modification not shown, the spindle gear 100; 200; 300; 400; 500, which can be driven by the motor 60, can be arranged in a central region of the first rail 12. The motor 60 and the motor mount 70 mounted between the two spindle gears 100; 200; 300; 400; 500 of the respective rail pairs are therefore also arranged in a central region of the first rail 12. The spindle 20 is held in a rotationally fixed manner, in particular fixed relative to the second rail 14, by means of two spindle holders. The first rail 12 is driven relative to the second rail 14 by screwing the spindle gear 100; 200; 300; 400; 500 along an external thread of the spindle 20.

[0032] Fig. 3 shows a side view of a pair of rails of the longitudinal adjuster 10 with the first rail 12 cut open in a first plane. The spindle 20 is rotatably mounted in the region of a rear end section 20b of the spindle 20 by means of a spindle holder. The spindle holder is designed as a pivot bearing 40 and held on the first rail 12. Alternatively, the spindle holder can be designed in the form of a plastic buffer for damping vibration of the spindle 20. In a region of a front end section 20a of the spindle 20, a spindle gear 100; 200; 300; 400; 500 is arranged for the rotational drive of the spindle 20. This spindle gear is held in a gear holder 54 that is firmly connected to the first rail 12.

[0033] Fig. 4 shows a partial longitudinal section through a pair of rails in the area of ​​the spindle gear 100; 200; 300; 400; 500. To support the individual gear elements of the spindle gear 100; 200; 300; 400; 500, a gear housing 52 is provided which, as a force-bearing housing, maximally fills an installation space defined between the gear holder 54 and the first rail with the greatest possible rigidity, and is therefore arranged essentially within the first rail 12. The gear housing 52 consists of two housing halves 52a, 52b; 52b, which abut one another in some areas and are screwed or riveted to one another. In the present case, only a first housing half 52a is shown. A second housing half 52b; 52b belonging to the gear housing 52 352b is not shown for technical reasons in order to allow a view into the interior of the spindle gear 100; 200; 300; 400; 500.

[0034] The first housing half 52a, in operative connection with the second housing half 52b, supports a drive worm 50b arranged transversely to the longitudinal direction x of the first rail 12. The drive worm 50b is operatively connected to a worm gear 50a mounted in the spindle gear 100; 200; 300; 400; 500. The worm gear 50a is rotatably mounted about a rotation axis A. In this case, the worm gear 50a is connected in a rotationally fixed manner to the spindle 20. For this purpose, the worm gear 50a, which has an internal thread section 58, is screwed onto the external thread of the spindle 20 in the front end section 20a of the spindle 20 and fixed by means of a locking element 34. The locking element 34 is pressed into a recess in the front end section 20a of the spindle 20 between the spindle 20 and the worm gear 50a.

[0035] The longitudinal adjuster 10 provides a press connection or crimp connection for the rotationally fixed connection of a front end portion 20a of the spindle 20 to the worm gear 50a. In this case, one or more securing elements 34 are pressed together by partially pushing them together between the front end portion 20a protruding forward from the worm gear 50a and a likewise forward-oriented portion of the worm gear 50a. These securing elements 34 are preferably annular or hollow-cylindrical in design and arranged on a thread-free front end portion 20a of the spindle 20.

[0036] The gear holder 54, which encloses the gear housing 52 and by means of which the spindle gear 100; 200; 300; 400; 500 is connected to the first rail 12, is essentially U-shaped. The spindle 20 is inserted through two parallel legs 54b of the gear holder 54. The two opposite legs 54b are preferably connected to one another in a conventional manner via a web 54a. Each of the legs 54b is adjoined by a fastening leg 54c, by means of which the gear holder 54 is attached to the first rail 12. The fastening legs 54c are further preferably bent or angled by approximately 90° relative to their respective leg 54b, in this case each bent in a direction away from the spindle gear 100; 200; 300; 400; 500. In the assembled state of the substantially U-shaped gear holder 54, the gear housing 52 is preferably received in the longitudinal direction x between the legs 54b.The fastening legs 54c have threaded holes by means of which, in interaction with corresponding screws and / or threaded bolts, a connection to the first rail 12 is established.

[0037] The following jointly described Fig. 5 to 7 show parts of a spindle gear 50 known from the prior art with an open gear housing 52, ie without a second housing half 52b.

[0038] The spindle gear 50 is enclosed by the gear housing 52. The gear housing 52 has two cylindrical bearing sections 53b for supporting a worm gear 50a connected to the spindle 20. The gear housing 52 has a step 53a adjacent to each of the cylindrical bearing sections 53b, wherein the step 53a is configured to support the worm gear 50a in the event of a crash.

[0039] A step 53a is arranged on each of the opposite outer sides of the gear housing 52. The steps 53a project radially inward relative to the cylindrical bearing section 53b. An inner diameter d1 of the steps 53a is smaller than an inner diameter d2 of the cylindrical bearing sections 53b. The gear housing 52 has a recess 53c in an upper section of the cylindrical bearing section 53b.

[0040] A worm gear 50a screwed onto the spindle 20 is mounted in the gear housing 52 by means of two bearing sleeves 56. The bearing sleeves 56 each have a substantially cylindrical base body and a collar 56a. Each bearing sleeve 56 has a projection 56b that interacts with the recess 53c of the gear housing 52. The bearing sleeves 56 are held in the gear housing 52 in a rotationally secure manner by means of the projections 56b. The gear housing 52 has a contact surface 53d that is axially aligned with the collar 56a of the bearing sleeves 56.

[0041] In the event of a crash, particularly a frontal or rear-end collision, the first rail 12 and the second rail 14 are loaded relative to one another in the longitudinal direction x by crash-related external forces. A force impulse introduced into the first rail 12 from the vehicle seat 1 must be transmitted to the vehicle via the gear holder 54, the spindle gear 50, the spindle 20, and the second rail 14, or vice versa. Such a load on the longitudinal adjuster 10 can lead to a comparatively very strong load on the worm gear 50a in the longitudinal direction x. The radially inwardly projecting steps 53a of the gear housing 52 offer the worm gear 50a additional support surfaces in the axial direction, or in this case essentially parallel to the longitudinal direction x, through which the load on the worm gear 50a in the longitudinal direction x can be better absorbed by the gear housing 52 and transmitted to the gear holder 54.

[0042] The following with reference to the Fig. The embodiments of the invention described in Figures 8 to 13 essentially correspond, unless explicitly stated otherwise, to the previously described spindle gear of the prior art. Identical components are provided with the same reference numerals.

[0043] Fig. 8 shows a spindle gear 100 without a second housing half 52b according to a first exemplary embodiment. The spindle gear 100 has a worm gear 50a mounted for rotation about a rotational axis A, which can be connected to a spindle 20, in particular via the internally threaded portion 58, in particular can be screwed onto an end portion of the spindle 20 and is secured by the securing element 34. Instead of connecting the worm gear 50a to the spindle 20 via the internally threaded portion 58, the worm gear 50a can alternatively have a rotationally asymmetric opening, which is plugged onto a rotationally asymmetric end portion of the spindle 20.

[0044] Furthermore, the spindle gear 100 has a drive worm 50b which can be connected to the motor 60 and driven by the motor 60 and which is in driving connection with the worm wheel 50a.

[0045] The worm gear 50a is mounted in the gear housing 52 by means of two bearing sleeves 56. The two bearing sleeves 56 are each arranged at one end of the worm gear 50a, axially to the rotational axis A of the worm gear 50a. The gear housing 52 has at least one cylindrical bearing section 53b for supporting the worm gear 50a, in particular with one of the bearing sleeves 50a interposed. The gear housing 52 has a recess 53c in the at least one cylindrical bearing section 53b.

[0046] The spindle gear 100 has a gear housing 52 enclosing the worm gear 50a and the drive worm 50b, wherein the worm gear 50a is axially aligned with the rotational axis A relative to the gear housing 52. To eliminate backlash of the worm gear 50a in the spindle gear 50, a spring-elastic means 110 is arranged axially aligned with the rotational axis A relative to the worm gear 50a in the first embodiment.

[0047] The resilient means 110 is preferably a clamping washer or a disc spring. According to the first embodiment of the spindle gear 100, the resilient means 110 is preferably configured to extend substantially completely around the rotational axis A. In an assembled state, the resilient means 110 can be clamped between the worm gear 50a, in particular a thrust washer of the worm gear 50a arranged directly thereon, and the adjacent collar 56a of the bearing sleeve 56. In the assembled state, the resilient means 110 can be clamped between the collar 56a of the bearing sleeve 56 and the adjacent contact surface 53d of the gear housing 52.

[0048] Fig. 9 shows a bearing sleeve 256 for use in the spindle gear 200 according to a second exemplary embodiment. According to the second exemplary embodiment of the spindle gear 200, a resilient means 210 is preferably arranged only in a circumferential section around the rotational axis A. The resilient means 210 is preferably a buffer element made of a plastic material. In an assembled state, the resilient means 210 can be clamped between the worm gear 50a, in particular a thrust washer of the worm gear 50a arranged directly thereon, and the respectively adjacent collar 56a of the bearing sleeve 256. In the assembled state, the resilient means 210 can be clamped between the collar 56a of the bearing sleeve 256 and the respectively adjacent contact surface 53d of the gear housing 52.

[0049] Fig. Figure 10 shows a second housing half 352b of the gear housing 52 for use in a spindle gear 300 according to a third embodiment of the invention. The housing half 352b has ribs 310 in the region of at least one contact surface 53d. For assembly of the spindle gear 300 according to the third embodiment, it is necessary that the remaining gear parts of the spindle gear 300, in particular the worm wheel 50a, the drive worm 50b and the bearing sleeves 56, are assembled in a manner similar to that shown in the Fig. 6 and Fig. 7, are arranged in the first housing half 52a. The worm wheel 50a arranged in the first housing half 52a initially has a play axially to the axis of rotation A. During a plugging together of the two housing halves 52a, 352b, in particular a plugging of the second housing half 352b onto the first housing half 52a, the ribs 310 cut at least partially into at least one of the bearing sleeves 56, in particular the collar 56a of the at least one bearing sleeve 56, and thereby clamp the worm wheel 50a axially to the axis of rotation A, so that the worm wheel 50a is set free of play.

[0050] Fig. 11 shows a perspective view of a bearing sleeve 456 for use in a spindle gear 400 according to a fourth embodiment of the invention. The bearing sleeve 456 has ribs 410 oriented in one half of a surface of the collar 56a, axially to the rotational axis A, in the direction of the contact surface 53d. To assemble the spindle gear 400 according to the fourth embodiment, it is necessary that the remaining gear parts of the spindle gear 400, in particular the worm wheel 50a, the drive worm 50b and the bearing sleeves 456, are assembled similarly to the Fig. 6 and Fig. 7, are arranged in the first housing half 52a. In this case, the bearing sleeve 456 with the ribs 410 arranged in sections is arranged in the first housing half 52a such that the section of the collar 56a with the ribs 410 is arranged outside the first housing half 52a. The worm gear 50a arranged in the first housing half 52a therefore initially has play axially to the axis of rotation A. During a plugging together of the two housing halves 52a, 52b, in particular during a plugging of the second housing half 52b onto the first housing half 52a, the ribs 410 are at least partially supported on the second housing half 52b, so that the bearing sleeve 456 clamps the worm gear 50a in the gear housing 400 axially to the axis of rotation A and the worm gear 50a is thus set free of play.

[0051] Fig. 12 shows a partial schematic view of two housing halves 52a, 52b with a bearing sleeve 556 for use in a spindle gear 500 according to a fifth embodiment, in a state during joining of the housing halves 52a, 52b. Fig. 13 shows the housing halves 52a, 52b and the bearing sleeve 556 of Fig. 12 in a state after joining the housing halves 52a, 52b.

[0052] The bearing sleeve 556 has a chamfer 510 in a transition region between the collar 56a and the substantially cylindrical base body. The chamfer 510 is preferably formed over its entire circumference. For the assembly of the spindle gear 500 according to the fifth embodiment, it is necessary that the inner gear parts of the spindle gear 500, in particular the worm gear 50a, the drive worm 50b and the bearing sleeves 556, are assembled similarly to the Fig. 6 and Fig.7, are arranged in the first housing half 52a. The bearing sleeves 556 are supported by their respective chamfers 510 on the first housing half 52a in such a way that the bearing sleeves 556, together with the worm gear 50a, are slightly pressed out of the first housing half 52a. During a mating of the two housing halves 52a, 52b, in particular during a mating of the second housing half 52b onto the first housing half 52a, the chamfer 510 serves as a run-on bevel. As a result, the two housing halves 52a, 52b displace the chamfer 510 of the respective bearing sleeve 556, so that the bearing sleeve 556 clamps the worm gear 50a in the gear housing 500 axially to the rotational axis A via the chamfer 510, and the worm gear 50a is thus set free of play.

[0053] The features disclosed in the above description, the claims and the drawings may be important both individually and in combination for the realization of the invention in its various embodiments.

[0054] Although the invention has been described in detail in the figures and the preceding description, these representations are to be understood as illustrative and exemplary, and not restrictive. In particular, the choice of the proportions of the individual elements shown in the drawings should not be interpreted as required or restrictive. Furthermore, the invention is not limited to the exemplary embodiments explained. Further variants of the invention and their implementation will become apparent to those skilled in the art from the preceding disclosure, the figures, and the claims.

[0055] Terms used in the claims such as "comprise," "have," "include," "contain," and the like do not exclude further elements or steps. The use of the indefinite article does not exclude a plurality. A single device may perform the functions of multiple units or devices mentioned in the claims. List of reference symbols 1 vehicle seat 2 seat part 4 backrest 10 longitudinal adjusters 12 first rail 14 second rail 16 inner channel 20 spindle 20a front end section (of spindle 20) 20b rear end section (of spindle 20) 30 spindle nut 34 Securing element 40 pivot bearings 50 spindle gears 50a worm gear 50b drive worm 52 Gearbox housing 52a first housing half 52b second housing half 53a level 53b cylindrical bearing section 53c recess 53d contact surface 54 Gearbox mount 54a footbridge 54b Thigh 54c mounting leg 56 bearing sleeve 56a collar 56b projection 58 internal thread section 60 engine 70 engine mounts 100 spindle gears 110 spring-elastic means, disc spring 200 spindle gears 210 spring-elastic means, buffer 256 bearing sleeve 300 spindle gears 310 ribs 352b second case half 400 spindle gears 410 ribs 456 bearing sleeve 500 spindle gears 510 chamfer 556 bearing sleeve A axis of rotation d1 inner diameter d2 inner diameter x longitudinal direction y transverse direction z Vertical direction

Claims

[1] Spindle gear (300; 400), in particular for a longitudinal adjuster (10), the spindle gear (300; 400) comprising: - a worm wheel (50a) mounted so as to be rotatable about an axis of rotation (A) and connectable to a spindle (20), - a drive worm (50b) connectable to a motor (60), by means of which the worm wheel (50a) can be driven, - a gear housing (52) enclosing the worm wheel (50a) and the drive worm (50b), wherein the worm wheel (50a) is positioned axially free of play relative to the rotational axis (A) of the gear housing (52), characterized byin that ribs (310; 410) are arranged in the region of at least one contact surface (53d) between one of the housing halves (52a, 352b) and a bearing sleeve (56; 456), wherein at least one of the housing halves (52a, 352b) has the ribs (310) in the region of at least one contact surface (53d) for one of the bearing sleeves (56), and the ribs (310) cut at least partially into at least one of the bearing sleeves (56) when the two housing halves (52a, 352b) are plugged together, and as a result the worm wheel (50a) is set free of play axially to the axis of rotation (A). [2] Spindle gear (300; 400) according to claim 1, wherein the gear housing (52) is formed from two housing halves (52a, 52b; 352b). [3] Spindle gear (300; 400) according to one of claims 1 or 2, wherein the worm wheel (50a) is mounted in the gear housing (52) by means of at least one bearing sleeve (56; 456), in particular by means of two bearing sleeves (56; 456). [4] Spindle gear (300; 400) according to one of claims 1 to 3, wherein the gear housing (52) has a recess (53c) in at least one cylindrical bearing portion (53b) and the at least one bearing sleeve (56; 456) has a projection (56b) which cooperates with the recess (53c) of the gear housing (52). [5] Spindle gear (300) according to one of claims 1 to 4, wherein the ribs (310) cut at least partially into at least one collar (56a) of at least one of the bearing sleeves (56) during a mating of the two housing halves (52a, 352b) and thereby the worm wheel (50a) is set free of play axially to the axis of rotation (A). [6] Spindle gear (400) according to one of claims 1 to 5, wherein the at least one bearing sleeve (456) has a collar (56a) and the collar (56a) of the at least one bearing sleeve (456) has the ribs (410) in one half of a surface, perpendicular to the axis of rotation (A), in the direction of a contact surface (53d), which ribs support the respective bearing sleeve (456) on the gear housing (52) in such a way that the worm wheel (50a) is thereby positioned axially free of play relative to the axis of rotation (A). [7] Longitudinal adjuster (10), in particular for a vehicle seat (1), the longitudinal adjuster (10) comprising at least one pair of rails which is formed from a first rail (12) and a second rail (14) which is displaceable in the longitudinal direction (x) relative to the first rail (12), wherein the rails (12, 14) alternately engage around one another to form an inner channel (16), wherein a spindle (20) mounted in the second rail (14) is arranged in the inner channel (16), wherein a spindle gear (300; 400) according to one of claims 1 to 6 is arranged in the first rail (12), which can be driven by means of a motor (60) and interacts with the spindle (20). [8] Vehicle seat (1) with a longitudinal adjuster (10) according to claim 7.

Images