Bearing assembly for supporting a helical gear shaft of a helical planetary gear and method for producing such a bearing assembly, including a helical planetary gear and motor-gear assembly, in particular for an adjustment device in vehicles for adjusting two mutually adjustable vehicle parts

Abstract

A bearing assembly for supporting a helical-wheel shaft of a helical planetary gear, in particular an adjustment device in vehicles for adjusting two mutually adjustable vehicle parts, wherein the helical-wheel planetary gear is a helical-wheel shaft with a helical-gear toothing, which shaft is rotatably mounted about a helical-wheel shaft axis, and a planetary carrier comprising at least three helical planetary gears, each rotatably mounted in the planetary carrier about a planetary gear axis, and each having a planetary gear toothing, wherein the helical gear planetary axes extend obliquely to the helical-wheel shaft axis, and the bearing assembly for supporting the helical gear shaft has a first bearing section and a second bearing section, wherein the first bearing section consists of an axial and radial bearing, and the second bearing section consists of helical-wheel planetary gears, wherein the planetary gear toothing in the second bearing section meshes with the helical-gear toothing.

Claims

1. A helical planetary gear system, comprising: an electric motor, and a helical gear shaft with helical-gear toothing, is the helical gear shaft being rotatably mounted about a helical gear axis; a planetary carrier having at least three helical planetary gears, each helical planetary gear of the at least three helical planetary gears mounted rotatably about a planetary gear axis in the planetary carrier, and each helical planetary gear of the at least three helical planetary gears having planetary gear toothing, wherein the helical planetary gear axes extend obliquely to the helical gear shaft axis; an inner helical gear having an inner toothing, which meshes with the planetary gear toothing; a bearing assembly for supporting the helical gear shaft comprising a first bearing section and a second bearing section; wherein the first bearing section is arranged outside the planetary carrier and comprises an axial and radial bearing; wherein the second bearing section comprises the helical planetary gears; a bearing seat, wherein the axial and radial bearing is arranged in the bearing seat, and wherein the bearing seat is arranged between the electric motor and the inner helical gear; and wherein the electric motor has a motor shaft, which is non-rotatably connected to the helical gear shaft.

2. The helical planetary gear system according to claim 1, wherein the inner helical gear is non-rotatably connected to the electric motor.

3. The helical planetary gear system according to claim 1, wherein the bearing seat is molded around the axial and radial bearing.

4. A method for producing a helical planetary gear system, comprising: providing a helical gear shaft having a first end, a second end, and a helical gear toothing; providing a first bearing section with an axial and radial bearing; providing a planetary carrier having at least three helical planetary gears, each helical planetary gear of the at least three helical planetary gears rotatably mounted about a planetary gear axis in the planetary carrier, and each helical planetary gear of the at least three helical planetary gears having a planetary gear toothing, wherein helical planetary gear axes extend obliquely to a helical gear shaft axis, and the planetary gears form a second bearing section; inserting the helical gear shaft into the first bearing section with the first end; and inserting the helical gear shaft into the second bearing section with the second end, such that the planetary gear toothing in the second bearing section meshes with the helical gear toothing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Exemplary embodiments of the present application are explained in more detail below with reference to the accompanying drawings. In the drawings:

(2) FIG. 1a) an exemplary embodiment of a proposed bearing assembly in a perspective view;

(3) FIG. 1b) the exemplary embodiment shown in FIG. 1a) in a lateral partial sectional view, each in the unassembled state;

(4) FIG. 1c) the exemplary embodiment shown in FIG. 1a) in a lateral partial sectional view in the assembled state;

(5) FIGS. 2-7 Various assembly steps for producing a proposed motor-gear assembly having a helical planetary gear with the bearing assembly shown in FIG. 1a), both in perspective views and lateral partial sectional views;

(6) FIGS. 8a) and 8b) Various illustrations of a helical gear shaft; and

(7) FIG. 9 a separate illustration of another embodiment of a bearing seat.

DETAILED DESCRIPTION

(8) FIGS. 1a) to 1c) show an exemplary embodiment of a bearing assembly 10 according to the present disclosure for supporting a first embodiment of a helical gear shaft 12.sub.1 of a helical planetary gear 14 (see FIG. 7). In FIG. 1a), the bearing assembly 10 is shown in a perspective view, while in FIG. 1b), the bearing assembly 10 is shown in a side view, showing the bearing assembly 10 in partial section there. Both in FIG. 1a) and FIG. 1b), the bearing assembly 10 is shown in the unassembled state, while FIG. 1c), shows the assembled state.

(9) The bearing assembly 10 includes the helical gear shaft 12.sub.1, which has a first end 16 and a second end 18. The helical gear shaft 12.sub.1 can be divided into a first section 20 and a second section 22, each having a substantially cylindrical shape. The first section 20 has a first diameter D1 and the second section 22 has a second diameter D2, the first diameter D1 being larger than the second diameter D2. The first section 20 forms the first end 16, while the second section 22 forms the second end 18.

(10) In addition, the helical gear shaft 12.sub.1 has helical gear toothing 24 arranged on the second section 22 and extending from the second end 18.

(11) Furthermore, the bearing assembly 10 comprises an axial and a radial bearing 26, which in the illustrated embodiment is designed as a rolling bearing 28, here as a ball bearing 30. The axial and radial bearing 26 forms a first bearing section 32 for supporting the helical gear shaft 12.sub.1.

(12) In addition, the bearing assembly 10 comprises a planetary carrier 34, in which three planetary gears 36 are rotatably mounted about a planetary wheel axle AP. The planetary gears 36 have planetary gear toothing 38, which is matched to the helical gear toothing 24 of the helical gear shaft 12.sub.1. The planetary gear toothing 38 form a second bearing section 40 for supporting the helical gear shaft 12.sub.1.

(13) As shown, in particular, in FIG. 1c), the first section of the helical gear shaft 12.sub.1 (20) is inserted into the axial and radial bearing 26, such that radially and axially acting forces may be transmitted from the helical gear shaft 12.sub.1 to the axial and radial bearing 26. For this purpose, the helical gear shaft 12.sub.1 may be molded with the first section 20 in the axial and radial bearings 26. Furthermore, the helical gear shaft 12.sub.1 with the helical gear toothing 24 is inserted into the second bearing section 40, such that the planetary gear toothing 38 of the planetary gears 36 meshes with the helical gear toothing 24. The helical gear shaft 12.sub.1 is thus rotatably mounted about a helical gear axis AS. It should be noted that the helical planetary wheel axles AP of the planetary gears 36 extend obliquely to the helical gear axle AS, as shown, in particular, in FIG. 1c).

(14) FIG. 1c), furthermore, shows that the second end 18 of the helical gear shaft 12.sub.1 does not project axially beyond the planetary gears 36 in the assembled state, but is enclosed sectionally by the helical gear planetary gears 36. Moreover, FIG. 1c) shows that the first bearing section 32 is arranged outside of the planetary carrier 34. The pressing of the helical gear shaft 12.sub.1 in the axial and radial bearings 26 can thus also be done outside of the planetary carrier 34, which simplifies assembly.

(15) FIGS. 2-7 show various process steps for producing a proposed motor-gear assembly 42 having the helical planetary gear 14 with the bearing assembly 10 shown in FIGS. 1a)-1c).

(16) Based on FIG. 1a), the helical gear shaft 12.sub.1 with its first section 20 is first pressed in the axial and radial bearing 26 to obtain the configuration shown in FIG. 2. The axial and radial bearing 26 shown in the exemplary embodiment formed as the ball bearing 30 has an outer 46 and an inner ring 48.

(17) The axial and radial bearing 26 is subsequently inserted into a bearing seat 44, as shown in FIG. 3. The inner ring 48 is connected to the first section 20 of the helical gear shaft 12.sub.1. The bearing seat 44 has a recess 50, whose diameter is roughly equal to the outer diameter of the outer ring 46. The outer diameter of the outer ring 46 may exceed the diameter of the recess 50 somewhat allowing for the outer ring 46 to be secured in the recess 50 by means of frictional engagement. Furthermore, the outer ring 46 axially abuts the bearing seat 44 in the recess 50, such that the axial and radial bearing 26 is secured in an axial direction.

(18) Subsequently, the bearing seat 44 is non-rotatably connected to an electric motor 52, as shown in FIG. 4. FIG. 3, in particular, shows that the bearing seat 44 has several projections 54, which engage in corresponding recesses 56 of the electric motor 52 and thus prevent the bearing seat 44 from rotating relative to the electric motor 52. To axially secure the bearing seat 44 against the electric motor 52, the projections 54 against the recesses 56 may be somewhat oversized in order for frictional locking to occur. Alternatively or cumulatively, the bearing seat 44 may also be glued, screwed or welded onto the electric motor 52.

(19) The electric motor 52 has a motor shaft 58 which projects from the electric motor 52. The helical gear shaft 12.sub.1 forms a motor shaft holder 59, with which the motor shaft 58 engages, when the bearing holder 44 is connected to the electric motor 52. The cross sections of the motor shaft 58 and the motor shaft holder 59 are selected such that a torque may be transmitted. For this purpose, the cross sections may be, e.g., square or hexagonal.

(20) FIG. 5 shows the planetary carrier 34 as illustrated in FIGS. 1a)-1c), now inserted into an inner helical gear 60, which has an internal toothing 62 matching the planetary gear 38. As shown in FIG. 6, a shim 64 is inserted into the inner helical gear 60 and brought into axial contact with the inner helical gear 60, after inserting the planetary carrier 34 into the inner helical gear 60, such that the planetary gear toothing 38 meshes with the inner toothing 62 of the inner helical gear 60.

(21) The inner helical gear 60 has an annular collar 66, with which the inner helical gear 60 is pushed onto a similarly shaped shoulder 68 of the bearing seat 44. Likewise, the helical gear toothing 24 is meshed with the planetary gear 38. The ball bearing 30 with the outer ring 46 rests against the shim 64, such that the ball bearing 30 rests axially against the bearing seat 44, and also against the shim 64, and is thus axially secured.

(22) In order to connect the inner helical gear 60 and the bearing seat 44 with one another, the inner helical gear 60 and the bearing seat 44 are welded together, e.g., by laser-transmission welding. The motor-gear assembly 42 is now fully installed. The inner helical gear 60 is rotatably secured to the bearing seat 44, which in turn is rotatably connected to the electric motor 52.

(23) The helical planetary gear 14 consists of the helical-gear shaft 12.sub.1, the planetary carrier 34, the helical planetary gears 36, and the inner helical gear 60. As the inner helical gear 60 is rotationally fixed, the power take-off occurs via the rotating planetary carrier 34, which has a slaving means 70 for a not-shown output shaft.

(24) FIGS. 8a) and 8b) show a second exemplary embodiment of the helical gear shaft 12.sub.2 in a perspective and a sectional view. In the second exemplary embodiment, the helical gear toothing 24 does not extend to the second end 18 of the helical gear shaft 12.sub.2, instead the helical gear toothing 24 forms a free end 72. Between the free end 72 and the second end 18 of the helical gear shaft 12.sub.2, a cylindrical section 74 is arranged, in which an axially extending bore 76 is arranged. The helical gear toothing 24 has a root diameter D3, which is greater than a diameter D4 of the cylindrical section 74.

(25) Although a shim 64 is provided for mounting, in conjunction with FIG. 7, this shim 64 is optional if the bearing seat 44as shown in FIG. 9has an anterior, inwardly projecting flange 44a, and this circumferential flange encloses the ball bearing 30, at least at its outer ring 46.

(26) FIG. 9 shows a further exemplary embodiment of a bearing seat in a sectional view, which is essentially the same as the sectional view of FIG. 3. In contrast to the illustration shown in FIG. 3, the bearing seat 44 is injection-molded around the axial and radial bearing 26. Consequently, when injection-molding the bearing seat 44, a unit consisting of the bearing seat 44 and the axial and radial bearing 26 is created, whereby the assembly step of inserting the axial and radial bearing 26 into the bearing seat 44 is omitted, thus simplifying assembly. Furthermore, the use of the shim 64 can be done away with, thus reducing the number of parts in this embodiment.

REFERENCE NUMERAL LIST

(27) 10 Bearing assembly 12, 12.sub.1, 12.sub.2 Helical gear shaft 14 Helical planetary gear 16 First end 18 Second end 20 First section 22 Second section 24 Helical gear toothing 26 Axial and radial bearing 28 Rolling bearing 30 Ball bearing 32 First bearing section 34 Planetary carrier 36 Planetary gear 38 Planetary gear toothing 40 Second bearing section 42 Motor-gear assembly 44 Bearing seat 46 Outer ring 48 Inner ring 50 Recess 52 Electric motor 54 Projection 56 Recess 58 Motor shaft 59 Motor-shaft holder 60 Inner helical gear 62 Inner toothing 64 Shim 66 Collar 68 Shoulder 70 Slaving means 72 Free end 74 Cylindrical section 76 Bore AP Planetary wheel axle AS Helical gear shaft axis D1 First diameter D2 Second diameter D3 Root diameter D4 Diameter of cylindrical section