DE102012106196B3 - Adjustment drive for a motor vehicle seat - Google Patents

Abstract

Adjustment drive (1) for a motor vehicle seat, with - a drive unit (3) mounted on a housing (2), - a spindle nut (4) arranged inside the housing (2) and driven by the drive unit (3), - one on the spindle nut (4) arranged in relation to the housing (2) adjustable in the longitudinal axis direction threaded spindle (5) and - a housing (2) at least partially surrounding the cage (6), the housing (2) being articulated to the cage (6) and Is guided against the cage (6) by a support element (7) arranged on the housing (2), characterized in that - in the area between the spindle nut (4) and the support element (7) for fixing the housing (2) opposite the cage (6) is arranged axially with a stop surface (9) on the spindle nut (4), compared to the support element (7) via a screw thread (10) axially adjustable to the spindle nut (4) spacer element (11).

Description

• – einer an einem Gehäuse gelagerten Antriebseinheit,
• – einer innerhalb des Gehäuses angeordneten, durch die Antriebseinheit antreibbaren Spindelmutter,
• – einer an der Spindelmutter angeordneten, gegenüber dem Gehäuse in Längsachsenrichtung verstellbaren Gewindespindel und
• – einem das Gehäuse zumindest teilweise umgebenden Käfig, wobei das Gehäuse gelenkig mit dem Käfig verbunden ist und über ein an dem Gehäuse angeordnetes Abstützelement an dem Käfig anliegend geführt ist.

The invention relates to an adjusting drive for a motor vehicle seat, with

• A drive unit mounted on a housing,
• A spindle nut, which can be driven within the housing and can be driven by the drive unit,
• - One arranged on the spindle nut, relative to the housing in the longitudinal axis direction adjustable threaded spindle and
• - A housing at least partially surrounding the cage, wherein the housing is pivotally connected to the cage and is guided over a arranged on the housing support member to the cage fitting.

Adjusting drives of the type mentioned are known in various embodiments from the prior art. In this case, at least part of the housing is located inside the cage and on the one hand hingedly connected to the cage and on the other hand guided to the cage fitting. Such an adjustment basically converts a rotational movement of the drive unit into a linear movement of the threaded spindle, this usually taking place via a transmission arranged therebetween. The threaded spindle can be pivoted in relation to the cage, whereby an additional degree of freedom of movement is available, as it is required for example in the construction of complex mechanisms, such as a spindle cage drive in a motor vehicle seat. An adjustment of the aforementioned type is from the document US 4,802,374 A known.

In order to ensure efficient operation, while the housing relative to the cage in the axial direction of the threaded spindle must be fixed without play, on the other hand, the pivotability of the housing on the cage should be minimized as possible. In particular, in a series production of the cage and the housing, there is always a certain variance of the dimensions, resulting in an undesirable play of the adjustment axially to the threaded spindle. This can easily lead to an imprecise function of the adjustment and noise during operation.

The skilled person is known to compensate for such a game by the fact that in the arrangement of the housing on the cage during assembly an individually adapted or appropriately selected spacer element, such as a spacer plate, a washer or a spring ring between the housing and the cage is arranged, which has the disadvantage that either an individual spacer element must be made or as precisely as possible spacer element is to be selected, whereby a fully automatic assembly is excluded. In addition, a complete compensation of the game is possible only in exceptional cases, whereby adverse effects, although reduced, but can not be avoided. In addition to the already mentioned impact noise and the imprecise operation, it can also lead to undesirable power losses due to excessive voltage and thus increased friction between the cage and housing. In addition, both increased friction and unwanted play leads to accelerated wear of the adjustment.

The invention has for its object to provide an adjustment with a pivotally mounted on a cage and supported against the cage housing, in which in a simple way the dimension of the housing can be precisely adapted to the dimensions of the cage, so that even in mass production Both components deviations in the building dimensions during assembly can be compensated cost-effectively and in a simple manner.

The object is achieved by a device according to claim 1. Advantageous developments of the invention are specified in the dependent claims.

The adjusting drive according to the invention for a motor vehicle seat has a drive unit mounted on a housing, a housing arranged within the housing, driven by the drive unit spindle nut, arranged on the spindle nut, relative to the housing in the longitudinal axis adjustable threaded spindle and the housing at least partially surrounding cage. In this case, the housing is pivotally connected to the cage and guided over an arranged on the housing support member to the cage fitting. In the area between the spindle nut and the support element for fixing the housing relative to the cage an axially with a stop surface on the spindle nut fitting, arranged relative to the support member via a screw thread axially adjustable to the spindle nut spacer element.

The over the screw thread of the spacer element in a simple manner adjustable arrangement of the support allows particularly easy and quick to adapt the dimension of the housing to the dimensions of the cage, whereby the game between the housing and cage can be adjusted individually and extremely precise. In this case, the installation effort is reduced compared to devices of the prior art, the assembly of all components can be done automatically and in a simple manner and in addition it is possible to adjust the adjustment at a later date in a particularly simple manner.

In principle, the housing can be designed in any desired manner and consist of any material, such as metal, a plastic, a composite material or a ceramic. The object of the housing is to hold the housing arranged on the components, such as the drive unit or the spindle nut, in a spatially fixed relation to each other and to unite to form an assembly which is hingedly connected via the housing with the cage. The housing can be formed in one piece or from several components and also fulfill other functions. In this case, the housing can partially or completely enclose the components arranged thereon.

In principle, the drive unit can be any desired means for driving. This is preferably an electrically operated motor, which is particularly preferably connected directly to a drive shaft. Mechanical solutions for the drive, such as mechanisms with prestressed springs or the transmission of a movement of another component via a shaft, a chain, a belt or the like are basically conceivable as a drive unit.

The spindle nut is fixed axially relative to the threaded spindle on the housing and acts via an internal thread with an external thread of the threaded spindle directly together. In this case, the spindle nut can basically be formed from any material, such as a metal, a plastic, a fiber composite or a ceramic. The spindle nut may be formed in one piece or from a plurality of components and fulfill other functions in addition to the function of a power transmission from the drive unit to the threaded spindle.

Preferably, the spindle nut is fixed to the housing in such a way that, on the one hand, the frictional forces occurring in a relative movement of the spindle nut relative to the housing are as low as possible, on the other hand, however, the spindle nut is guided sufficiently firmly against the housing, so that substantially only a rotation of the spindle nut on the housing is possible, but not angling, a tilt or a translation.

In principle, the threaded spindle can have any shape and be formed from any material, such as a metal, a plastic or a composite material. In this case, the threaded spindle has at least one region which has a constant outer diameter orthogonal to the central longitudinal axis of the threaded spindle and has an external thread. The outer diameter and the outer thread are designed such that this region of the threaded spindle can interact with the internal thread of the spindle nut. A rotation of the spindle nut fixed to the housing then leads to a linear displacement of the threaded spindle with respect to the housing along the central longitudinal axis in the longitudinal axis direction, with the further requirement that the threaded spindle is connected to another component secured against rotation about the central longitudinal axis.

The threaded spindle can be formed integrally or consist of several components. Preferably, the region of the threaded spindle which has the external thread is at least as long, more preferably at least 1.5 times as long and most preferably at least twice as long as the housing along a direction of the central longitudinal axis of the threaded spindle arranged on the housing via the spindle nut , Further preferably, the spindle nut has at least one end an area to which a fastening means can be attached and by means of which the linear movement of the spindle can be transmitted during operation.

The support element can in principle be shaped in any desired manner and consist of any material, such as a metal, a plastic, a composite material or a ceramic. Preferably, it is formed from the same material as the housing. In this case, the support element can be arranged arbitrarily on the housing and thereby rest partially or completely on a part of the housing or form part of the housing itself, so that the support element closes an open area of the housing.

The cage is any component that at least partially surrounds the housing and to which the housing is hinged, thereby allowing movement of the housing relative to the cage. In this case, the housing can preferably not completely detach from the cage during operation. The cage can surround the housing only partially or even on all sides, wherein the cage can have any number of openings. In principle, the cage can be formed from any material, such as a metal, a plastic, a composite material or a ceramic. In addition, the cage can fulfill even more functions, wherein it is preferably the task of the cage to fasten the housing so as to be pivotable relative to another component, for example a part of a motor vehicle seat structure. For this purpose, the cage preferably has at least one fastening means or a fastening area Attachment, in particular on the motor vehicle seat or the vehicle seat structure, on.

The housing is hinged to the cage. An articulated connection can first be understood to mean any connection which permits mobility between the housing and the cage and in which at least one reference point between the cage and the housing is spatially fixed. This may be a tilting movement in one or more spatial directions, a rotatability along one or more axes or an overlapping of the aforementioned tilting movements and rotations. By contrast, a translation along one or more spatial directions is essentially prevented by the articulated arrangement.

The spacer element is rotatably arranged about a central longitudinal axis of the spindle nut and thereby axially supported on a stop surface along the central longitudinal axis of the spindle nut on this. In this case, the spacer element at least in a section of a screw, preferably an external thread that cooperates with another screw on the support, preferably an internal thread, such that by rotation of the spacer relative to the spindle nut or the housing, the support along the central longitudinal axis Spindle nut is moved. The spacer may be formed of any material, such as a metal, a plastic or a composite material.

The abutment surface of the spacer element preferably has a particularly smooth surface, so that the spacer element supported by the stop surface on the spindle nut can be rotated relative to the spindle nut, the frictional forces occurring being small.

According to another embodiment of the invention may also be arranged a spacer to reduce the friction between the spindle nut and the spacer element. In this case, preferably at least one surface of the spacer is smooth and / or consists of a material having a low coefficient of friction in contact with the spindle nut or the spacer element.

According to an advantageous embodiment of the invention, the housing completely surrounds the components arranged thereon, the threaded spindle being guided out of the housing through recesses on two sides. In addition, the housing preferably has at least one removable cover, by means of which a part of the housing can be opened and closed again. The components inside the housing are thus protected in a particularly simple manner from contamination, with a repeated engagement by the removable cover, such as readjustment or maintenance, is still possible.

According to an advantageous embodiment of the invention, the spacer element is designed as a bearing element between the spindle nut and the support element, preferably as a sliding bearing, whereby the spindle nut and the support element with respect to each other can be rotated particularly easily and wear of both components by mechanical friction in a particularly simple manner is reduced.

In a particularly advantageous embodiment of the invention, the spacer element has an adjusting element or an adjusting element is arranged on the spacer element, which is accessible through an opening in the housing from the outside, preferably by means of a tool, and by means of which the spacer element can be rotated relative to the spindle nut.

According to an advantageous embodiment of the invention, the screw thread between the spacer element and the support element can be materially blocked, wherein it is preferably designed such that a substance, in particular an adhesive, can be supplied to the cohesive connection of both threaded parts, which in a particularly simple manner the screw thread can be secured against undesired adjustment. For this purpose, the thread is preferably designed in such a way that the substance can be well supplied to the cohesive connection and distributed on the thread. This can be done for example by channels, grooves or interruptions of the thread on the spacer element and / or on the support element.

According to a further advantageous embodiment of the invention, a locking device is provided, by means of which the screw thread between the spacer element and the support element can be positively or positively locked, wherein preferably a locking element is provided as part of the locking device. Such a locking device makes it possible to secure the screw thread against undesired rotation in a particularly advantageous manner, with very particular preference the locking device can be reversibly operated, whereby in a simple manner a repeated adjustment of the support element is possible.

Preferably, the support element has a smooth and / or curved surface, which is particularly preferably adapted to the shape of a portion of the cage, which cooperates with the support element, whereby a secure and uniform guidance of the support element on the cage during movement of the housing in the cage is guaranteed. Most preferably, the support member is arranged on the housing such that it is not rotatable relative to the housing.

According to a preferred embodiment of the invention, the support member and the housing are shaped and arranged to each other, that the support element can not lose contact with the housing in an adjustment to the screw thread between the support element and spacer element. This can be achieved in that a part of the support element protrudes into the housing and is guided during an adjustment by means of the screw thread of the spacer element on the housing. This can be done for example by means of interlocking grooves or in another form-fitting manner.

According to an advantageous embodiment of the invention, the support member relative to the housing by means of the screw thread by at least 5 mm, preferably at least 10 mm, more preferably adjusted by at least 20 mm, thereby adapting a corresponding game between the cage and the housing in a particularly simple Way becomes possible.

According to an advantageous embodiment of the invention, the spindle nut and / or the drive unit on the outside of a toothing on which cooperate both components. In this case, a rotation axis of the spindle nut and a rotation axis of the drive unit are preferably arranged substantially orthogonal to one another. Particularly preferably, both components act together as a worm gear, wherein very particularly preferably the spindle nut are designed on its outer side as a helical worm wheel and the drive unit as a shaft with a helical external thread. In this way, the shaft of the drive unit and the outside of the spindle nut form a gear stage that can be designed with a high gear ratio. In addition, an embodiment as a worm gear has the advantage that due to the strong self-locking of a worm gear with stationary drive unit, the threaded spindle is effectively secured against external force and a resulting displacement along the central longitudinal axis.

According to an advantageous embodiment of the invention protrudes at least one end of the threaded spindle, preferably both ends of the threaded spindle out of the cage, wherein the cage has at least one opening, preferably at least two openings which are dimensioned such that unimpeded pivoting of the housing and the thereto arranged spindle is possible.

According to a further advantageous embodiment of the invention, the pivotable articulation of the housing takes place on the cage by means of at least one nose or an axis on one of the two components and an adapted receptacle on the other component, whereby a pivoting in a spatial direction is possible in a particularly simple manner while effectively preventing rotation or pivoting in another spatial direction.

According to a further embodiment of the invention, the cage and / or the housing at least a portion which can be closed and reopened. Particularly preferably, both the cage and the housing each have at least one lid, whereby in closed lids, a malfunction of the operation of the outside and contamination are effectively prevented and at the same time all components are accessible in a simple manner when needed.

An embodiment of the invention will be explained below with reference to the drawings. In the figures show:

1 a schematic sectional view through a central longitudinal axis of a threaded spindle of an embodiment of an adjustment;

2 a perspective view of the partially assembled, in 1 illustrated embodiment of the adjusting drive;

3 a 180 ° rotated exploded view of the in 2 illustrated, partially assembled embodiment of the adjustment and

4 a perspective view of the fully assembled, in 1 illustrated embodiment of the adjustment.

An in 1 illustrated embodiment of an adjustment 1 for a motor vehicle seat comprises one on a housing 2 mounted drive shaft 3 and one inside the housing 2 arranged spindle nut 4 , where the drive shaft 3 and the spindle nut 4 interact as a worm gear. At the spindle nut 4 is one opposite the case 2 in the longitudinal axis adjustable threaded spindle 5 arranged. All components are formed from a metal, in particular a steel.

To the case 2 there is a cage around 6 arranged. The housing 2 is with the cage 6 hingedly connected and one on the housing 2 arranged support plate 7 on a side of the cage opposite the articulation 6 guided fitting, wherein the support plate 7 so on casing 2 is arranged that a rotation with respect to the housing 2 not possible.

To the case 2 the exact inside dimension of the cage 6 to be able to adjust and the housing 2 opposite the cage 6 precise and with a desired contact pressure of the support plate 7 opposite an inner wall 8th of the cage 6 to be able to determine is in the area between the spindle nut 4 and the support plate 7 an axial with a stop surface 9 on the spindle nut 4 fitting, opposite the support plate 7 via a screw thread 10 axially to the spindle nut 4 adjustable slide bearing 11 arranged (cf. 2 ). The plain bearing has 11 the function, the spindle nut 4 on the support plate 7 and also on the housing 2 to store. In addition, the plain bearing allows 11 a precise adjustment of the distance between the on the spindle nut 4 arranged housing 2 and the support plate 7 ,

The on the case 2 mounted drive shaft 3 is powered by an electric motor that drives the drive shaft 3 around a first axis of rotation 12 drives. The drive shaft 3 works with the spindle nut 4 as a worm gear together, with the spindle nut 4 on its outside as a helical worm wheel and the drive shaft 3 are designed with a helical external thread.

A rotation of the drive shaft 3 around the first axis of rotation 12 causes a translated rotation of the spindle nut 4 around a second axis of rotation 13 passing through both the central longitudinal axis of the spindle nut 4 as well as the threaded spindle 5 runs. The spindle nut 4 is on the one hand on the sliding bearing 11 on the case 2 arranged support plate 7 and on the other hand via a second sliding bearing 14 directly on the housing 2 rotatably mounted.

The threaded spindle 5 acts via an external thread with an internal thread of the spindle nut 4 together. Is the threaded spindle 5 firmly connected to another component which is to be moved via the threaded spindle, and thus secured against rotation about the central longitudinal axis, so causes a rotation of the spindle nut 4 around its axis of rotation 13 a linear displacement of the threaded spindle 5 along the central longitudinal axis.

To another component with the threaded spindle 5 To connect, has the threaded spindle 5 at a spindle end 16 a surface with a hole.

The housing 2 points in the axial direction of the threaded spindle 5 or the spindle nut 4 two openings on, leaving the threaded spindle 5 depending on the set position in the spindle nut 4 at least with a spindle end 16 , but mostly with two spindle ends 16 . 17 out of the case 2 sticking out. The openings on the housing 2 have a slightly larger diameter than the threaded spindle 5 , whereby on the one hand the threaded spindle 5 in the axial direction freely with respect to the housing 2 is movable, on the other hand, a penetration of foreign bodies in the housing 2 is prevented.

The housing 2 is formed as an assembly of three components - from a housing base on which the spindle nut 4 and the drive shaft 3 can be arranged, the support plate 7 that is part of the case 2 closes, as well as a cover plate 22 by means of the housing 2 can be closed and which can be disassembled if necessary, to those in the housing 2 arranged components can get to and optionally the distance of the support plate 7 to the housing 2 by turning the screw thread 10 on the plain bearing 11 to be able to vary (cf. 3 and 4 ).

The housing 2 is with the cage 6 articulated over one on the housing 2 shaped nose 20 in a picture 21 in the cage 6 engages, connected. This will cause the housing to pivot 2 in relation to the cage 6 possible in one spatial direction, the maximum deflection being determined by the size of the interior of the cage 6 in relation to the size of the case 2 is limited. A secure guidance of the housing 2 on the cage 6 is achieved by a continuous contact of the support plate 7 on the inner wall 8th of the cage 6 Ensures and at the same time prevents the nose 20 from the recording 21 of the cage 6 can solve.

For efficient adaptation of the game between the cage 6 and the support plate 7 of the housing 2 , Especially in mass-produced components, the distance between the support plate 7 and housing 2 be varied in that the sliding bearing 11 by means of a tool with fixed spindle nut 4 is rotated, causing an axial displacement of the support plate 7 along the screw thread 10 between plain bearings 11 and support plate 7 can be achieved. After adjustment, the screw thread becomes 10 firmly bonded by means of an adhesive to prevent undesired adjustment.

The rotation of the plain bearing 11 by means of a tool does not take place on the plain bearing 11 itself, but at one between the sliding bearing 11 and the spindle nut 4 arranged adjusting ring 15 which has notches on the outside in which the tool can grip. The adjusting ring acts 15 on the one side opposite the plain bearing 11 frictionally over a rough surface and form-fitting via recesses in the surface, which in a corresponding surface structure of the sliding bearing 11 grip, and on the other side has a particularly smooth surface, which is a sliding with low friction on the spindle nut 5 allows.

In a further embodiment, instead of the adjusting ring 15 a particularly smooth spacer ring between the spindle nut on both sides 5 and plain bearings 11 arranged and the rotation of the plain bearing 11 by means of a tool takes place directly on the plain bearing 11 , In yet another embodiment, there is no further component between the spindle nut 5 and plain bearings 11 intended.

The cage 6 has two recesses 18 . 19 on, through each one end of the spindle 16 . 17 out of the cage 6 can protrude out, with the recesses 18 . 19 are dimensioned such that a free pivoting of the housing 2 and the threaded spindle arranged thereon 5 is possible without causing contact between threaded spindle 5 and cage 6 comes.

For the cage 6 a side cover plate is provided by means of the cage 6 reversible can be closed, whereby penetration of foreign bodies is prevented.

LIST OF REFERENCE NUMBERS

1

adjustment

2

casing

3

drive unit

4

spindle nut

5

screw

6

Cage

7

supporting

8th

Contact section

9

stop surface

10

screw thread

11

spacer

12

axis of rotation

13

axis of rotation

14

bearing device

15

adjustment

16

spindle end

17

spindle end

18

recess

19

recess

20

Nose / axle

21

admission

22

cover

Claims (10)

Adjusting drive ( 1 ) for a motor vehicle seat, with - one on a housing ( 2 ) mounted drive unit ( 3 ), - one within the housing ( 2 ), by the drive unit ( 3 ) drivable spindle nut ( 4 ), - one on the spindle nut ( 4 ), with respect to the housing ( 2 ) in the longitudinal axis adjustable threaded spindle ( 5 ) and - the housing ( 2 ) at least partially surrounding cage ( 6 ), the housing ( 2 ) hinged to the cage ( 6 ) and via a on the housing ( 2 ) arranged supporting element ( 7 ) on the cage ( 6 ) is guided fitting, characterized in that - in the area between the spindle nut ( 4 ) and the supporting element ( 7 ) for fixing the housing ( 2 ) opposite the cage ( 6 ) an axial with a stop surface ( 9 ) on the spindle nut ( 4 ) abutting, opposite the support element ( 7 ) via a screw thread ( 10 ) axially of the spindle nut ( 4 ) adjustable spacer element ( 11 ) is arranged. Adjusting drive according to claim 1, characterized in that the spacer element ( 11 ) as a bearing element, preferably as a plain bearing, between the spindle nut ( 4 ) and the supporting element ( 7 ) is designed. Adjusting drive according to claim 1 or 2, characterized in that the spacer element ( 11 ) an adjusting element ( 15 ) by means of which the spacer element ( 11 ) relative to the spindle nut ( 4 ) can be twisted. Adjusting drive according to at least one of the preceding claims, characterized in that the screw thread ( 10 ) between the spacer element ( 11 ) and the supporting element ( 7 ) can be fixed cohesively, wherein the screw thread ( 10 ) is preferably designed such that a substance, in particular an adhesive, can be supplied to the cohesive connection of both threaded parts. Adjusting drive according to at least one of the preceding claims, characterized in that a locking device is provided, by means of which the screw thread ( 10 ) between the spacer element ( 11 ) and the supporting element ( 7 ) can be locked force or positive locking, wherein preferably a locking element is provided as part of the locking device. Adjusting drive according to at least one of the preceding claims, characterized in that the supporting element ( 7 ) has a smooth and / or curved surface which preferably conforms to the shape of a contact section ( 8th ) of the cage ( 6 ) connected to the support element ( 7 ) is adjusted. Adjusting drive according to at least one of the preceding claims, characterized in that the supporting element ( 7 ) opposite the housing ( 2 ) by means of the screw thread ( 10 ) around at least 5 mm, preferably at least 10 mm, more preferably at least 20 mm can be adjusted. Adjusting drive according to at least one of the preceding claims, characterized in that a first axis of rotation ( 12 ) of the spindle nut ( 4 ) and a second rotation axis ( 13 ) of the drive unit ( 3 ) are arranged substantially orthogonal to each other and thereby preferably both components ( 3 . 4 ) cooperate as worm gear, wherein particularly preferably the spindle nut ( 4 ) on its outside as a helical worm wheel and the drive unit ( 3 ) are designed as a shaft with a helical external thread. Adjusting drive according to at least one of the preceding claims, characterized in that at least one end ( 16 . 17 ) of the threaded spindle ( 5 ), preferably both ends ( 16 . 17 ) of the threaded spindle ( 5 ) out of the cage ( 6 protrude, with the cage ( 6 ) at least one recess ( 18 . 19 ), preferably at least two recesses ( 18 . 19 ), which are dimensioned such that unimpeded pivoting of the housing ( 2 ) and the threaded spindle ( 5 ) in the cage ( 6 ) is possible. Adjusting drive according to at least one of the preceding claims, characterized in that the pivotable articulation of the housing ( 2 ) on the cage ( 6 ) by means of at least one nose ( 20 ) or an axis ( 20 ) on one of the two components ( 2 . 6 ) and a recording adapted to it ( 21 ) on the other component ( 6 . 2 ) he follows.

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