DE19602926C1 - Shaft in housing, for seat adjusting drives, etc. - Google Patents

Abstract

One end of the shaft (1) is supported via a bearing body on a contact face of the transmission housing. The bearing body (11) is connected articulated to the shaft end (4), forming a single modular group. One group element supports itself on a support face of the other element, or an insert (20) connected to it. The surface area (12) of the bearing body engaging on the contact face of the transmission housing is flat. The bearing body is located in a recess (21) in the shaft. It is formed as a flattened ball.

Description

The invention relates to a stored in a housing Shaft, in particular for gearboxes of adjustment devices in motor vehicles, according to the preamble of claim 1.

Such a gear shaft for an adjustment drive in Motor vehicles are known from DE 38 15 356 A1. This Document shows a worm gear with a Gear housing, a worm rotatably mounted in the housing wheel and a worm meshing with the worm wheel,  wherein at least one end of the worm shaft on one Contact surface on its part on the gear housing supporting insert. The support of the The shaft end on the contact surface is done via a rei exercise-reducing, centrally arranged to the shaft axis hump-like elevation, so that a point load at the bearing point works. A rubberized metal part is featured as an insert see to stop tensions of the worm gear to diminish.

This known worm gear has the disadvantage that the low-friction and low-wear design of the axial bearing requires a correspondingly high installation effort. Before the worm can be inserted into the gear housing there are still several preparatory steps to be carried out ren: To prevent that at the front shaft end hump-like elevation arranged centrally to the shaft axis due to the loads occurring in operation in the Material of the gearbox incorporated and given around if an additional axial suspension has to be reached an insert with a contact surface for the front Worm shaft end in a suitable installation space of the Ge drive housing to be attached. Furthermore, the contact area surface of the insert are greased to reduce friction to reduce the point bearing.

The invention has for its object a gear for Adjustment devices in motor vehicles at the beginning to create the type that is easy and quick to assemble can be.  

According to the invention, this object is characterized by the solved the features of claim 1.

The solution according to the invention is characterized above all by this from that serving for the axial bearing of a shaft Bearing body itself with a flattened, evenly formed Surface area on the designated contact surface supports the housing.

By this measure, the surface pressure in the loading rich, in which the bearing body on the contact surface of the housing ses applied, reduced. Therefore, the bearing body directly on a contact surface of the housing or one support component connected to the housing without it is necessary between the bearing body and the contact surface che a special insert, e.g. B. a pressure piece or a pot socket to arrange.

The bearing body is also articulated with the shaft end connected. This means that the shaft and the bearing body form a uniform assembly, which is already before Inserting the shaft into the housing is created. (So This creates an axial bearing integrated in the shaft.) the articulated formation of this connection is secured represents that in operation even with a slight inclination of the The shaft of the bearing body is always flattened Surface area to the associated contact surface of the Can create housing.  

The articulated connection between the shaft end and the bearing bracket per is realized in a low-friction manner by that one of the two components (bearing body or Shaft end) point-like on a supporting surface of each other component or one connected to it Insert part supported. Because the contact with the housing Surface area of the bearing body is flattened, acts a point load in the transmission according to the invention exclusively on the articulated connection of the bearing body and shaft end.

The inventive design of the axial storage the bearing body serving the shaft and its (articulated) Connection with a shaft end facilitate the assembly of the Shaft in one housing considerably. The wave can be in one Work step can be inserted into the housing without the previously special components for supporting the shaft in axially fixed in the housing and given if you need to grease. This will not only Assembly costs reduced, but also possible sources of error switched off during assembly.

Under a housing is the rotatable storage understood a necessary assembly shaft. The exact Ge staltung this housing is for the present invention irrelevant. In particular, the term "housing" is not to understand in its narrow sense as a closed component hen.

From the German utility model 74 41 431 is a shock - absorbing bearing for a rotating shaft journal in known small instruments or clockwork, in which the Shaft journal articulated in connection with a bearing body  stands. However, this known bearing is neither one punctiform still a pre-assembled connection between the shaft and the bearing body provided.

From DE 27 39 721 A1 and DE 42 09 835 A1 are also Known ball joint connections, which is an articulated connection between a rod-shaped component (e.g. a Piston rod or a ball stem) and a bearing body demonstrate. However, the rod-shaped element and the Bearing body with each other over a large area in operative connection. Such storage is quick rotating shafts of adjusting devices in motor vehicles unsuitable and would lead to high friction losses in the Operate. This also applies to the steering linkage for Motor vehicles, which is known from DE-OS 19 16 578.

In the bearing according to the invention, the bearing body is in front preferably in a recess of the at least one arranged axial bearing serving shaft end.

This variant of the invention can, for. B. realized thereby be that the bearing body is formed as a flattened ball det, the flattened surface area of the system Surface of the housing is facing and its surface at a solid angle of more than 2 π from the wall of the Recess is included in the shaft. The term solid angle is related here in its classic meaning with spherical coordinates for the description of rotational symmetry understood body. Accordingly, a complete one Spherical surface with a solid angle 4 π This means that in the present case more than half of the spherical surface of the Wall of the recess is included in the shaft. This can  the spherical bearing body in the recess of the shaft be held securely even when there are no axial forces act on the flattened spherical surface that the sphere press into the recess. This is especially true of Meaning if the shaft after the bearing body in it was ordered, is still to be transported.

If for structural reasons an elongated design of the bearing body is preferred, it can be provided that the bearing body is designed as a ball with a extension that is rotationally symmetrical with respect to the shaft axis is provided with a flat surface area is supported on the contact surface of the housing. Because the Bearing body even with an elongated design has spherical section, its attachment in a recess of the shaft facilitated.

In another advantageous variant of the invention the bearing body is provided with a recess in which the Shaft end is arranged.

This variant of the invention can in particular ver become real that the shaft end is spherical det and that its surface at a solid angle of more than 2π from the wall of the recess of the bearing body pers is included. This means more than half the spherical surface from the wall of the recess in the Wave is embraced.  

The bearing body is preferably designed as a bush det, one end of which consists of a flat surface, which rests on a contact surface of the housing, and by the second end of the shaft end into the recess of the bearing body protrudes.

To avoid tension that occurs in particular ten when in an end stop position of an adjustment the drive motor did not drive until a short time after starting switches off at the time of the strike and compensate for tolerances to be able to, the insert is resilient. Of the The bearing body is accordingly in the direction of the system surface of the housing spring loaded. This will make the Degree of tension of the gearbox when starting an An impact significantly reduced, so Umschalt-Knackge noise can be largely avoided and the wear of the Camp is reduced.  

The insert is preferably a resilient pressure plate, especially designed as a rubberized metal plate. The Me The tall surface then forms the low-friction and low-wear Support surface for the bearing body. An elastomer spring on The back of the metal part allows the one you want Springback even after long periods of operation.

In other preferred embodiments of the invention the insert part is designed as a plate spring, or it is by one made of a resilient material, in particular one viscous, curable elastomer existing hump-like Survey formed.

The aforementioned embodiments of the invention with a Resilient insert element allow axial compensation Tolerances and tension. There are no additional ones Steps when inserting the shaft into a gearbox housing necessary. Because the necessary measures to manufacture development of a low-friction and low-wear as well as given if resilient axial bearings can be Manufacturing the shaft can be done by the bearing body and, if necessary, the necessary insert parts or pre-assembled in the shaft. The one with an inte The axially supported shaft bearing can then directly into the Housing are used.

For some applications of the invention it is advantageous to if both ends of the shaft are each over a bearing body support each on a contact surface of a housing.  

In particular in the implementation of the invention in the Input stage of a transmission can be provided that at least one end of the shaft including the bearing bracket pers arranged in a recess of the gear housing is. This can also radial of the gear housing Powers are absorbed.

One on the gear shaft mounted according to the invention Ordered gear element can, for. B. out as a snail be educated. The worm can be used with a worm wheel Drive a rope window regulator or with a rack Comb to drive a cross arm window lifter.

To drive the shaft itself, a second, preferably designed as a worm gear gear ment to be provided with a drive in operative connection manure stands. The gear shaft can also be a component a commutator motor and have a commutator. This is particularly advantageous if the engine housing se, the gearbox and the electronics housing one Adjustment drive for motor vehicles a compact unit should form.

Various preferred embodiments are described below men of the invention explained in detail with reference to the figures.

Show it:

Fig. 1 - is a screw provided with a shaft, at both ends thereof a flattened, rotationally symmetrical bearing body each is provided for the axial mounting;

Figure 2 - a variant of the thrust bearing according to the invention with a flattened ball as a bearing body.

Fig. 3 - a second embodiment of the axial bearing fiction, contemporary with a flattened ball and a rubberized metal part to the springs of the support;

Fig. 4 - another embodiment of the example of Figure 3, in which the ball has a rotationally symmetrical extension.

Fig. 5 - another embodiment of the invention with a flattened ball for the axial position tion of the shaft, wherein a silicone drop is provided as a resilient insert;

Fig. 6 - a fourth embodiment of the invention with a flattened ball for the axial position tion of the shaft, wherein a plate spring is provided as a resilient insert part;

Fig. 7 - a variant of the invention, in which the shaft end provided with the axial bearing is mounted in a recess of the gearbox housing;

Fig. 8 - a variant of the invention, in which the bearing body has a recess in which the spherical shaft end is arranged;

Fig. 9 - an example of the arrangement of the transmission shaft according to the invention housed in a gearbox.

Fig. 1 shows a shaft 1, on which a worm 2 and a worm wheel 3 are mounted. The two shaft ends 4 and 4 'are rotatably gela in bearing rings 6 and 7 , which form self-centering spherical bearings due to their spherical outer circumference.

At the shaft ends 4 and 4 'is also an end face, with the shaft axis 5 aligned cylindrical recess 21 and 21 ' is provided. In the recesses 21 , 21 ', a spherical, flattened bearing body is arranged by 11 or 11 '.

The spherical bearing body 11 and 11 'are supported on the rear inner wall of the recesses 21 and 21 ' point-like over resilient insert elements 20 and 20 '. Further details on the storage of the bearing body by 11 , 11 'in the recesses 21 , 21 ' of the shaft ends 4 , 4 'are explained below with reference to FIGS. 2 to 6.

The shaft 1 shown in Fig. 1 is driven by the worm wheel 3, which can be accommodated for this purpose with a drive in operative connection. The worm 2 again, for example, can mesh with a worm wheel that is coupled with the cable pulley of a cable window regulator. Likewise, the worm 2 can be provided for driving the toothed segment lever of a cross arm window lifter.

Furthermore, its use in electrical seat adjusters equipment or for adjusting sunroofs and the like possible.

For this purpose, the worm 2 is usually arranged in a gearbox housing, the spherical, flattened bearing bodies 11 and 11 'serving to axially support the worm shaft 1 .

The particular advantage of the embodiment shown in FIG. 1, the axial bearing of the screw shaft 1 lies in the fact that the bearing bodies 11 and 11 ', including any necessary resilient insert portions 20 and 20' gene in suitable Ausnehmun 21 and 21 'of the shaft 1 and hence in this are integrated. The worm 2 can therefore be inserted without further preparatory work steps for its axial mounting in a gear housing and fastened there. In particular, the flattened surface areas of the balls 11 and 11 'are important, via which the shaft 1 can be supported on suitable contact surfaces of the gear housing. Due to the flattened, flat design of the surface areas of the balls 11 and 11 'facing the gear housing, the surface pressure which occurs when axial forces are transmitted from the shaft 1 to the transmission housing is reduced. This eliminates the need to arrange additional insert parts between the bearing bodies 11 and 11 'and the associated contact surfaces of the Getriebegehäu ses.

Fig. 2 shows a first embodiment of an integrated in a recess 21 of the worm shaft 1 Axialla gers. In the recess 21 , a spherical bearing body 11 is inserted with a flattened, flat surface area 12 (flattened rolling elements). With this surface area 12 , the shaft 1 can be supported on a suitable contact surface of the gear housing. Characterized the spherical bearing body 11 is pressed against the rear inner wall 22 of the recess 21 , so that a point load acts at position 15 .

Since the front end 24 of the wall of the cylindrical Ausneh tion 21 is bent inwards, the flattened ball 11 is covered at a solid angle of more than 2π from the wall of the recess. As a result, the ball 11 can also be held securely in the recess 21 when no axial forces act on the wall 22 on the surface region 12 thereof. This means in particular that the ball 11 is already in the recess 21 before the insertion of the shaft 1 in a gear housing and the shaft 1 can be stored and transported in this preassembled state.

Because of the spherical design of the bearing body 11 and its point-like support on the support surface 22 of the shaft 1, there is an articulated connection between the shaft 1 and the bearing body 11 . This ensures that in operation, even with a slight inclination of the shaft 1, the bearing body 11 can always create with its flattened upper surface area 12 on the associated contact surface 32 of the housing 31 (see FIGS . 7 and 9).

In order to reduce the friction in the bearing and to avoid bearing contamination, the recess 21 is also filled with grease.

Another embodiment of the bearing integrated into shaft 1 according to the invention is shown in FIGS . 3a and 3b. The bearing shown in FIG. 3b differs from the embodiment according to FIG. 2 in that a metal printing plate 25 is provided in the recess 21 , which is supported on the rear wall of the recess 21 via an elastomer or rubber spring 26 . The flattened ball 11 is accordingly supported on the surface 22 of the metal printing plate 25 , so that a point load acts there at position 15 . Due to the resilient design of the insert part 25 , 26 , the degree of tension of the transmission when starting a stop of an adjusting device is significantly reduced. Furthermore, 15 tolerances can be compensated for by the suspension of the bearing point. The load on the bearing point 15 is determined by the axial force F with which the surface area 12 of the ball 11 is pressed against the associated contact surface of the gear housing. As in the exemplary embodiment according to FIG. 2, the region of the recess 21 surrounding the ball 11 is also provided with lubricating grease.

FIG. 3a shows the bearing according to FIG. 3b in the preassembled state, that is to say before the shaft 1 has been inserted into a gear housing. Even if no axial forces act on the surface area 12 of the ball 11 , it cannot slip out of the recess 21 . Because by the inwardly curved front 24 of the wall of the recess 21 , more than half of the surface 16 of the ball 11 is covered by the wall of the recess 21 . The remaining cavity of the recess 21 is filled with grease, which fixes the position of the ball 11 in the recess 21 and in particular the orientation of the surface region 12 . The bent shaft end 24 also prevents dirt from entering the recess 21 or lubricant escaping from it. The bearing integrated in the shaft 1 can then be easily transported, stored and kept ready for further assembly steps in the preassembled state because the bearing body 11 is held in a form-fitting manner in the recess 21 .

The embodiment according to FIG. 4 differs from the previous exemplary embodiment only with regard to the design of the bearing body 11 , 13 . According to FIG. 4, the bearing body of a spherical rear portion 11 which is held in the recess 21 of the shaft 1, and an adjoining cylindrical, the shaft axis bezüg Lich 5 rotationally symmetric portion 13, the flat, planar front face 14 for bearing against an corresponding contact surface of a transmission housing is provided.

The embodiment of Fig. 5 differs from Fig. 3 in terms of the design of the resilient A set element.

Referring to FIG. 5, the resilient insert member is formed of a silicone drop 27, the flattened ball 11 in the recess 21 of the shaft 1 against the dot located on the bearing 15 is supported point-like.

It is also possible to use a plate-shaped plate spring 28 , which can also be slotted, as the resilient insert element. This embodiment of the invention is shown in FIG. 6.

In the exemplary embodiments from FIGS. 3 to 6, the resilient insert elements 25 , 26 , 27 , 28 are not only supported on the rear wall of the recess 21 , but are also secured against lateral sliding by the side walls of the recess 21 . As a result, the axial parts cannot escape laterally.

In summary, the exemplary embodiments of FIGS. 2 to 6 show the important advantages of the solution according to the invention, with which an axial bearing, which is integrated in the shaft 1 , is created. This is pre-greased and sealed and has only a single bearing point 15 , whereby particularly low coefficients of friction are achieved.

FIGS. 7a and 7b show embodiments of the dung OF INVENTION which are particularly when they are used in a transmission Eingangsstu fe advantageous.

Fig. 7a shows a worm shaft 1 with a worm 2 , the front end 4 is housed in the recess 35 of the housing 31 Getriebege. The axial bearing is the spherical bearing body 11 , which is supported with the flattened surface area 12 on the contact surface 32 in the recess 35 of the gear housing 31 . A point load is only present at position 15 in this thrust bearing, where the bearing body 11 is supported against the rear wall of the recess 21 in the gear shaft 1 .

This type of bearing is particularly advantageous in the input stage of gearboxes, where high speeds, a high axial pressure and high thermal loads often only have a low radial pressure. Due to the large-area interaction of the surface area 12 of the ball 11 and the contact surface 32 of the gear housing 31 compared to a point load, the surface pressure is sufficiently limited in spite of the large axial forces, so that the bearing body by 11 without the interposition of a cup bushing or the like directly at the Bearing surface 32 of the gear housing 31 can rest without damaging the housing. The gearbox housing, which can consist of a magnesium alloy, for example, generally has a much better thermal conductivity than the sintered metal bushings typically used. The solution according to the invention therefore not only has the advantage that a pot bushing is saved in the axial bearing, but the heat generated by friction can also be dissipated better.

By arranging the shaft end 4 including the bearing body 11 in the recess 35 of the Getriebegehäu ses 31, the transmission housing 31 takes up radial forces.

Fig. 7b shows a further embodiment of the invention, in which one end 4 of the shaft 1 is arranged in a recess 35 'of the gear housing 31 . This embodiment differs from Fig. 7a on the one hand in terms of the design of the recess 35 '. The recess 35 'is here directly to the shape of the front shaft end 4 is. On the other hand, the spherical bearing body 11 is resiliently mounted in the recess 21 of the shaft 1 with the aid of the insert part 20 . This enables tolerances and axial tension to be better compensated.

Fig. 8 shows a further preferred variant of the solution according to the invention. One end 41 of the shaft 1 is spherical and is arranged in the recess 54 of a bush-like bearing body 51 . The surface 42 of the shaft end 41 is so comprised of the wall 54 of the recess 54 bent inwards at its front end 53 that it is held securely in the recess 54 filled with grease.

In the recess 54 of the bearing body 51 , a rubberized metal pressure plate 25 , 26 is also provided, on the metallic support surface 22 of which the shaft end 41 is supported point-like at position 15 .

In this variant of the invention, the bearing body 51 rests with the flat surface area 52 on a bearing surface of a transmission housing provided for this purpose.

Fig. 9 schematically shows a possible arrangement of the transmission shaft 1 according to the invention in a Getriebegehäu se 31st This is based on flattened surface areas 12 , 12 'of the bearing body arranged in recesses of the shaft 1 on opposite contact surfaces 32 and 32 ' of the gear housing 31 . (In the uncut depicting lung shown in FIG. 9, the bearing body are largely concealed by the shaft 1.) The shaft 1 has at its rear end 4 ', a worm gear 3, on which they drive nut from the on 8 is driven. The worm 2 itself is in operative connection with the toothed segment of a lever arm 9 , which can be part of a cross arm lifter, for example.

Fig. 9 shows only an example of the possible arrangement of the screw 1, 2 in a gear housing 31. For the sake of clarity, the presentation of further details, such as. B. the calottes from Fig. 1 waived. Many variants are conceivable in addition to that shown in FIG. 9. On the one hand, this relates to the design of the transmission housing itself. This is not subject to any particular restrictions when using the solution according to the invention. It only has to have at least one contact surface for the axial mounting of a gear shaft. In particular, it is not necessary for the transmission housing to be a closed structure.

A lot of possibilities are also conceivable for the design of the gear shaft 1 . Thus, the bearing according to the invention can also be used with the motor shaft of a commutator motor which is provided with a commutator. Likewise, various designs of Zahn Zahnele element 2 are conceivable, which need not be a snail.

Claims (16)

1. In a housing rotatably mounted shaft of a transmission for adjusting devices in motor vehicles, such as seat adjustments, window regulators or the like. At least one end of the shaft is supported axially via a bearing body axially on a flat contact surface of the transmission housing or of a component connected to the transmission housing, characterized in that the bearing body ( 11 , 11 ', 51 ) is articulated to the shaft end ( 4 , 4 ', 41 ) and the two components form a unitary, preassembled assembly, one of the two components being punctually on a support surface ( 22 ) of the other component or an insert connected to this part ( 20 , 25 , 26 , 27 , 28 ), and that the surface area ( 12 ) lying against the contact surface ( 32 , 32 ') of the transmission housing ( 31 ) 12 ', 52 ) of the Lagerkör pers ( 11 , 11 ', 51 ) is flat. 2. Device according to claim 1, characterized in that the bearing body ( 11 , 11 ') in a recess ( 21 , 21 ') of the shaft ( 1 ) is arranged. 3. Apparatus according to claim 2, characterized in that the bearing body ( 11 ) is ausgebil det as a flattened ball, the flat surface area ( 12 ) abuts the contact surface ( 32 ) and the surface at a solid angle of more than 2 π from the wall the recess ( 21 ) in the shaft ( 1 ) is included. 4. Apparatus according to claim 2 or 3, characterized in that the bearing body ( 11 ) is ausgebil Det as a ball, which is provided with a with respect to the shaft axis ( 5 ) ro tationsssymmetrischen extension ( 13 ) having a flat, frontal surface area ( 14 ) on the contact surface ( 32 ). 5. The device according to claim 1, characterized in that the shaft end ( 41 ) in a recess ( 54 ) of the bearing body ( 51 ) is arranged. 6. The device according to claim 5, characterized in that the shaft end ( 41 ) is spherical and that its surface ( 42 ) is covered at a solid angle of more than 2π from the wall of the recess ( 54 ) of the bearing body ( 51 ). 7. The device according to claim 5 or 6, characterized in that the bearing body ( 51 ) is designed as a socket, one end face of which consists of a flat surface ( 52 ) which abuts a contact surface of the housing ( 31 ), and by the second end face ( 55 ) the shaft end ( 41 ) in the recess ( 54 ) of the Lagerkör pers ( 51 ) protrudes. 8. Device according to one of the preceding claims, characterized in that the insert part ( 20 , 25 , 27 , 28 ) in a direction parallel to the shaft axis ( 5 ) is resilient. 9. The device according to claim 8, characterized in that the insert part ( 25 , 26 ) is designed as a resilient pressure plate, in particular as a rubberized metal plate. 10. The device according to claim 8, characterized in that the insert part ( 28 ) is designed as a plate spring. 11. The device according to claim 8, characterized in that the insert part ( 27 ) is formed by a hump-like elevation consisting of a resilient material, in particular a viscous, curable elastomer. 12. Device according to one of the preceding claims, characterized in that the two ends ( 4 , 4 ') of the shaft ( 1 ) each have a bearing body ( 11 , 11 ') on a respective bearing surface ( 32 , 32 ') of Support the housing ( 31 ). 13. Device according to one of the preceding claims, characterized in that the shaft end ( 4 ) is finally arranged a bearing body ( 11 ) in a recess ( 35 , 35 ') of the housing ( 31 ). 14. Device according to one of the preceding claims, characterized in that on the shaft ( 1 ) a preferably designed as a worm gear transmission element ( 2 ) is mounted. 15. The apparatus according to claim 14, characterized in that on the shaft ( 1 ), a second, preferably designed as a worm gear gear element ( 3 ) is provided, which is in active connection with a drive ( 8 ). 16. Device according to one of the preceding claims, characterized in that the shaft ( 1 ) is part of a commutator motor.