ELECTROMOTIVE ANCILLARY UNIT

Abstract

An electromotive ancillary unit of a motor vehicle, particularly a seat adjustment, having a mounting plate and an adjustment drive having an electric motor and a gearing mechanism. The gearing mechanism is disposed within a gearbox closed by means of a cover through which an output shaft connected to the gearing mechanism protrudes. The gearbox is mounted on the mounting plate, and the cover abuts to the mounting plate via a damping element in the axial direction of the output shaft. The invention further relates to a seat of a motor vehicle having a seat adjustment.

Claims

1. An electromotive ancillary unit of a motor vehicle, particularly a seat adjustment, the electromotive ancillary unit comprising: a mounting plate; and an adjustment drive comprising an electric motor and a gearing mechanism disposed inside of a gearbox and closed via a cover through which an output shaft connected to the gearing mechanism protrudes, wherein the gearbox is mounted to the mounting plate, wherein the cover abuts to the mounting plate via a damping element in an axial direction of the output shaft, wherein the cover comprises a collar that circumferentially surrounds the output shaft and a first portion of the collar is disposed between the damping element and the output shaft in a direction perpendicular to the axial direction, and wherein the mounting plate circumferentially surrounds the collar and directly abuts to a second portion of the collar.

2. The electromotive ancillary unit according to claim 1, wherein the damping element circumferentially surrounds the output shaft.

3. (canceled)

4. (canceled)

5. The electromotive ancillary unit according to claim 1, wherein the damping element is a washer.

6. The electromotive ancillary unit according to claim 1, wherein the damping element is made of rubber and/or the mounting plate is made of a metal.

7. The electromotive ancillary unit according to claim 1, wherein the cover and/or the gearbox are formed of a plastic material.

8. The electromotive ancillary unit according to claim 1, wherein the gearing mechanism comprises a worm drive and/or tumble gearing.

9. The electromotive ancillary unit according to claim 1, wherein the output shaft is provided with a pinion that is integrally formed, and/or wherein the electric motor is a commutator motor provided with brushes.

10. A seat of a motor vehicle comprising electromotive ancillary unit according to claim 1, wherein the electromotive ancillary unit is a seat adjustment.

11. The electromotive ancillary unit according to claim 1, further comprising a bearing element that is non-integrally mounted on the output shaft, the bearing element having a circumferential collar, wherein an outer surface of the collar of the bearing element abuts an internal surface of the collar of the cover and wherein a coefficient of friction the bearing element is smaller than a coefficient of friction of the collar of the cover.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0025] FIG. 1 shows a schematically facilitated view of a seat of a motor vehicle comprising a seat adjustment,

[0026] FIG. 2, 3 shows respective perspective views of an adjustment drive of the seat adjustment,

[0027] FIG. 4 shows an exploded view of the seat adjustment,

[0028] FIG. 5 shows a perspective view of a section of the adjustment drive, and

[0029] FIG. 6, 7 shows a respective sectional view of the seat adjustment.

DETAILED DESCRIPTION

[0030] FIG. 1 shows a schematically facilitated view of a seat 2 of a motor vehicle comprising a seating area 4 and a backrest 6. Below the seating area 4, the mechanics 8 of an electromotive ancillary unit 10 in the form a seat adjustment are disposed. A position of the seating area 4 and the backrest 6 connected thereto is changed by means of the mechanics 8, both being either lifted or lowered. In other words, a height adjustment is concerned. The electromotive ancillary unit 10 comprises an adjustment drive 12 connected to a control unit 14 in terms of signalling or electrically. The control unit 14 itself is connected to a sensing device 16 in terms of signalling. During operation, the sensing device 16 is activated by a user. This is detected by means of the control unit 14, and depending thereon, the adjustment drive 12 is operated to which end an electric current flow towards it is established. The mechanics 8 are driven by means of the adjustment drive 12. Consequently, the height of the seating area 4 and the backrest 6 connected to it are changed.

[0031] In FIG. 2 a perspective view of the adjustment drive 12 is shown. It comprises an electric motor 18 which is a commutator motor provided with brushes. On the face side, the electric motor is mounted on a gearbox 20 of a gearing mechanism 22 manufactured from a plastic material by means of an injection moulding method. The gearbox 20 comprises a recess 24 closed by a cover 26. The cover 26 is formed of the same plastic material as the gearbox 20 and also produced by means of a plastic injection moulding process.

[0032] As shown in FIG. 3, the pot-shaped cover 26 comprises studs 28 protruding to the outside and located in associated grooves 30 of the gearbox 20. A anti-twist protection of the cover 26 relative to the gearbox 20 is realised by means of the studs 28 and the grooves 30. The cover 26 has a central opening 32 formed by a collar 34 having a hollow cylindrical design. The collar 34 is disposed at the bottom of the pot-shaped cover 26 and is directed away from the gearbox 20. An output shaft 36 provided with a pinion 38 protrudes through the opening 32 and therefore through the collar 34. The pinion 38 is integrally and therefore monolithically formed with the output shaft 36. The output shaft 36 is supported so as to be rotatable about a rotational axis 38 which is parallel to an axial direction 40. The collar 34 is rotationally symmetric with regard to the rotational axis 38 here, and therefore also extends in axial direction 40. The output shaft 36 protrudes through the collar 34 which therefore circumferentially surrounds the output shaft 36.

[0033] As shown in FIG. 3 with the gearbox 20 removed, the gearing mechanism 22 is provided with a worm drive 42 the worm gear 44 being superimposed to a motor shaft 46 of the electric motor 18. This constituent part of the motor shaft 46 is disposed within the gearbox 20 in the mounted state. A worm wheel 48 of the worm drive is disposed on an intermediate shaft 50 and drives it.

[0034] In FIG. 4, the electromotive ancillary unit 10 is partially shown in an exploded view. The gearing mechanism 20 further comprises a tumble gearing 52 which comprises a ring-shaped guide disk 54 and a crossbar 56. By means of these, a tumbling wheel 58 is guided in a plane which is perpendicular to the axial direction 40, an intrinsic rotation of the tumbling wheel 58 relative to the crossbar 56 being prevented by detents 60 of the tumbling wheel 58 which engage in associated retainers 62 of the crossbar 56. The tumbling wheel 58 is moved within the plane by means of an eccentric tappet 64 disposed on the intermediate shaft 50. In the course of these movements the tumbling wheel 58 provided with exterior teeth engages in an internal gearing 66 of the output shaft 36 and rolls along in it as shown in FIG. 5. Consequently, the output shaft 36 is set into a rotary motion about the rotational axis 38.

[0035] On the output shaft 36, a bearing element 68 in the form of a plain bearing ring is mounted which is circumferentially surrounded by the collar 34 of the cover 26. The output shaft 36 is stabilised within the opening 32 of the cover 26 by means of the bearing element 68. In addition, friction of the output shaft 36 during a rotary motion about the rotational axis 38 is reduced by means of the bearing element 68.

[0036] The electromotive ancillary unit 10 further comprises a damping element 70 in the form of a washer disposed perpendicular to the axial direction 40. The damping element 70 is made of an elastic rubber and circumferentially abuts to the collar 34. Consequently, the damping element 70 circumferentially surrounds the output shaft 36. In other words, the collar 34 is disposed between the damping element 70 and the output shaft 36. Further, the electromotive ancillary unit 70 comprises a mounting plate 72 in the form of a lateral seat plate part. The mounting plate 70 is manufactured of metal which is, for example, powder-coated. The mounting plate 72 has an opening 74 in which the free end of the collar 34 is disposed as shown in FIG. 6 in a lateral sectional view and in FIG. 7 in a perspective sectional view. Therefore, the mounting plate 72 which has a substantially planar design and extends perpendicular to the axial direction 40 circumferentially surrounds the collar 34 and abuts to it forming a clearance fit. Therefore, the output shaft 36 is disposed between the cover 26 and the mounting plate 72 of the damping element 70 in the axial direction 40, the cover 26 abutting to the mounting plate 72 via the damping element 70 in the axial direction 40.

[0037] The mounting plate 72 is mounted on the gearbox 22 by means of three screws 76 guided through an associated screw opening 78 in the mounting plate 72. Therefore, is the cover 26 abuts to the mounting plate 72 via a damping element 70 in the axial direction 40 of the output shaft 36. Vibrations of the cover 26 relative to the mounting plate 72 are attenuated by means of the damping element 70 so that they will not be transmitted to the mounting plate 72. Consequently, no excitation of the mounting plate 72 will take place which will be transmitted to the cover 26 due to the engagement of the teeth of the gearing mechanism 20. Thereby, the acoustic impression during the operation of the seat adjustment 10 is improved.

[0038] The invention is not limited to the embodiment described above. Rather, other variants of the invention can be derived by persons skilled in the art without deviating from the subject matter of the invention. In particular, all individual features described in connection with the embodiment can be further combined in other ways without deviating from the subject matter of the invention.

[0039] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.