Gear assembly, transmission device and adjusting device for motor vehicle

Abstract

The invention relates to a gear assembly (10) comprising a gear (14) and at least one stop disc (30, 32) having a substantially annular stop surface (54), the gear (14) having an axis of rotation (16) and teeth (18) arranged about the axis of rotation (16), the teeth (18) being provided with teeth (22) and tooth gaps (24) arranged alternately in a circumferential direction (20) about the axis of rotation (16), the teeth (18) having at least one axial end face (34, 36), the teeth (22) being provided with teeth (22) and tooth gaps (24) being provided with teeth (22) and tooth gaps (24) arranged alternately in the circumferential direction (20) about the axis of rotation (16). At least one stop disk (30, 32) having a recess (38) extending about the axis of rotation (16), the at least one stop disk (30, 32) having at least one disk projection (56) projecting radially above the stop surface (54) and being arranged in the recess (38) in such a way that the at least one disk projection (56) engages radially in each of the tooth gaps (24); and a transmission device (72) having the gear assembly (10); the invention further relates to an adjusting device for a motor vehicle, in particular for a motor vehicle seat.

Description

Technical Field

[0001] The present invention relates to a gear assembly, a transmission device having such a gear assembly, and an adjustment device for a motor vehicle. Background Technology

[0002] Seat longitudinal adjustment devices are frequently used for electrically adjusting the longitudinal position of seats in motor vehicles. These devices typically have a main shaft drive mechanism that transmits speed and torque between a worm gear and the main shaft. For this purpose, a main shaft nut is mounted on the main shaft, and this nut has a toothed ring with external teeth for engaging with the worm gear.

[0003] To support the spindle nut, a sliding bearing is typically used, arranged in a bearing housing on the spindle nut axially adjacent to the external teeth. In particular, when the external teeth are constructed as helical teeth, it is necessary to provide appropriate support to the spindle nut in the axial direction, taking into account the resulting axial forces. Therefore, it is necessary to provide an axial stop surface on the spindle nut, configured to form a sliding contact with the sliding bearing. To provide such a stop surface on the axial end face of the external teeth, the prior art uses a stop disc to cover the axially open external teeth. For the sliding contact to be definitively formed between the sliding bearing and the stop disc, the stop disc must be arranged on the spindle nut in an anti-rotation manner. Various different solutions are known to prevent the stop disc from rotating relative to the spindle nut.

[0004] For example, DE102013207665A1 recommends pressing the stop disc onto the spindle nut. However, the disadvantage of doing so is that the pressing process may cause chip generation and deformation of the stop disc. Both of these conditions can lead to premature failure of the drive mechanism.

[0005] As known from KR101920222B1, a stop disc with an axial protrusion is provided, which can engage in the axial direction between two teeth of the external toothed portion. A disadvantage of this solution is that the manufacture of the stop disc is relatively complex.

[0006] The stop disc shown in DE10362040B4 has a radial protrusion that bends axially after the stop disc is mounted on the spindle nut, thus enabling axial engagement between two teeth of the external gear. A drawback of this system is that additional manufacturing steps are required to bend the radial protrusion when mounting the stop disc on the spindle nut. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide a gear assembly in which a stop disc can be simply and reliably arranged on the end side of the gear teeth. The present invention also aims to provide a corresponding transmission device and a corresponding adjustment device for a motor vehicle.

[0008] According to the present invention, these objectives are achieved by a gear assembly having the features of claim 1, a transmission device having the features of claim 12, and an adjustment device having the features of claim 15.

[0009] Advantageous designs and modifications of the invention are described in the dependent claims. A gear assembly according to the invention comprises a gear and at least one stop disc having a substantially annular stop surface, wherein the gear has a rotation axis and teeth arranged around the rotation axis, the teeth having alternating teeth and tooth clearances in a circumferential direction about the rotation axis, wherein each tooth has at least one axial end side having a groove extending around the rotation axis. Thus, each tooth may have a first portion and a second portion disposed axially rearward relative to the first portion. Preferably, the tooth is radially defined on one side by a root circle diameter and on the other side by a head circle diameter. Thus, the groove can be divided by the tooth clearance. Preferably, the tooth is configured as an external tooth, preferably defined radially outward by a head circle diameter and radially inward by a root circle diameter. Unless otherwise stated, the terms "radial" and "axial" as used herein and hereinafter refer to the axis of rotation.

[0010] According to the invention, at least one stop disc has at least one disc protrusion that projects radially relative to the stop surface, and is arranged in a groove such that the at least one disc protrusion radially engages in one tooth gap. Thus, at least one stop disc can be easily manufactured and can be fixedly arranged on the gear during the manufacturing process to prevent torsion. Therefore, at least one stop disc can be arranged on the gear such that at least one disc protrusion is supported on a tooth flank radially adjacent to the groove. Therefore, no additional fixing structure, such as a (particularly axial) fixing groove, is required on the gear side. Preferably, at least one disc protrusion is arranged in one of the tooth gaps only radially engaged. The stop surface is described as substantially annular, meaning that the free cutting surface of the protrusion of at least one disc protrusion can be cut from the stop surface.

[0011] Preferably, at least one end side has at least one shoulder that defines a groove in the radial direction. The at least one shoulder is preferably configured as annular. Preferably, at least one end side has exactly one shoulder.

[0012] At least one shoulder preferably has a shoulder diameter, wherein the shoulder diameter is particularly preferably configured to be smaller than the head circle diameter of the tooth and larger than the root circle diameter of the tooth. Therefore, the shoulder can be divided by the tooth gap.

[0013] At least one shoulder may be arranged to define a groove radially inward and / or radially outward. Preferably, depending on the arrangement of the at least one shoulder, at least one disc protrusion may be configured to project radially inward and / or radially outward from the stop surface. Particularly preferably, at least one shoulder is arranged to define a groove only inward. In this case, the corresponding first portion of the tooth is radially arranged within the corresponding second portion of the tooth.

[0014] The tooth portion may have a tooth height, and at least one shoulder may have a shoulder height, wherein the ratio of the shoulder height to the tooth height is 0.05 to 0.3, preferably 0.05 to 0.15. The tooth height described herein and hereinafter is preferably understood as the difference between the head circle diameter and the root circle diameter. When the tooth portion is configured as an external tooth portion, the tooth height is preferably expressed as the difference between the shoulder diameter and the root circle diameter, while when the tooth portion is configured as an internal tooth portion, the tooth height is preferably expressed as the difference between the shoulder diameter and the head circle diameter. The axial shoulder width of at least one shoulder preferably corresponds substantially to the axial disk width of at least one stop disk.

[0015] In a preferred embodiment of the invention, the gear and at least one stop disc are interacting and connected only by form-locking. In this case, the at least one stop disc may have radial and axial clearances relative to the gear. Therefore, preferably, there is no frictional locking between the at least one stop disc and the gear. Thus, in particular, the at least one stop disc can be arranged on the gear without generating chips or causing deformation of the at least one stop disc.

[0016] In an improved embodiment of the invention, the protrusion profile of at least one disc protrusion is at least partially mathematically similar to the clearance profile of one of the tooth gaps. Therefore, the degree of freedom of movement of at least one stop disc relative to the gear can be reduced, particularly in the circumferential direction. Preferably, the protrusion profile is similar to a portion of the clearance profile, i.e., the portion in which the corresponding disc protrusion engages. In particular, the protrusion profile can be constructed in such a way that it is centrally compressed compared to the corresponding portion of the clearance profile. Therefore, a suitable clearance between at least one stop disc and the gear can be achieved.

[0017] At least one stop disc may have multiple disc protrusions. Each disc protrusion preferably has the features of at least one disc protrusion as described above. Preferably, at least one stop disc has three to nine disc protrusions. Particularly preferably, the disc protrusions are evenly spaced in the circumferential direction.

[0018] In an improved embodiment of the invention, the gear has at least one radial bearing housing arranged axially adjacent to the teeth. Preferably, the at least one radial bearing housing is axially adjacent to the teeth, and a free cutting surface for the bearing housing is provided between the teeth and the radial bearing housing. The at least one radial bearing housing is preferably constructed in a cylindrical shape. Preferably, the gear is a one-piece structure.

[0019] According to a preferred embodiment, the gear is configured as a spindle nut. The spindle nut preferably has a threaded through hole formed along the axis of rotation for receiving a threaded spindle.

[0020] In an improved embodiment of the invention, a first stop disc of at least one stop disc is arranged on a first end side of at least one end side, and a second stop disc of at least one stop disc is arranged on a second end side of at least one end side, wherein the second end side and the first end side are axially opposite each other. Therefore, the gear can be axially supported on both sides of the teeth.

[0021] The transmission device according to the invention, particularly the adjustment device for motor vehicles, includes the aforementioned gear assembly.

[0022] The transmission device preferably has at least one sliding bearing, wherein the at least one sliding bearing has an axial bearing portion arranged to axially abut against the stop surface of at least one stop disc. Therefore, the axial force acting on the gear can be supported by at least one stop disc and the sliding bearing. The axial bearing portion can be arranged on the transmission device housing, with its rear side positioned axially opposite the stop surface.

[0023] In a preferred embodiment, at least one sliding bearing has a radial bearing portion perpendicular to the axial bearing portion, wherein the radial bearing portion is arranged to abut against a radial bearing housing, and wherein... The axial inner diameter of the axial bearing portion is greater than or equal to the inner diameter of the stop surface, and / or The axial outer diameter of the axial bearing portion is less than or equal to the outer diameter of the stop surface.

[0024] The axial inner diameter and axial outer diameter preferably define the contact surface of at least one sliding bearing, which is configured to contact the interface of the object to be axially supported, particularly the stop surface of at least one stop disc. In a half-section, at least one sliding bearing may be L-shaped. At least one sliding bearing may be constructed such that the radial bearing portion and the axial bearing portion are each arranged near the chamfer connecting the radial bearing portion and the axial bearing portion.

[0025] The adjustment device for motor vehicles, particularly for motor vehicle seats, according to the present invention includes the aforementioned transmission device. Preferably, the adjustment device is configured as a seat longitudinal adjustment device, particularly for a longitudinal adjustment device for motor vehicle seats. Attached Figure Description

[0026] Embodiments of the present invention will be explained with reference to the accompanying drawings. In the drawings: Figure 1 A perspective view of an embodiment of a gear assembly having a main shaft nut and two stop discs is shown; Figure 2 It shows Figure 1 The embodiment shown is an end-side side view, in which section CC is shown; Figure 3 It shows Figure 1 The illustrated embodiment, along Figure 2 The cross-sectional view shown is a section cut by section CC. Figure 4 It shows Figure 1 A perspective view of the spindle nut in the embodiment shown; Figure 5 It shows Figure 4 The end-side side view of the spindle nut shown, in which section AA is shown; Figure 6 It shows Figure 4 The spindle nut shown, along Figure 5 The sectional view shown is a section cut by section AA; Figure 7 It shows Figure 1 Perspective view of one of the stop discs in the illustrated embodiment; Figure 8 A perspective view of an embodiment of a transmission device having a main shaft nut and a rotating axis is shown; Figure 9 It shows Figure 8 The illustrated embodiment shows a longitudinal section cut along the axis of rotation. Detailed Implementation

[0027] Figures 1 to 9 Various embodiments are shown. The same reference numerals are used for the same and functionally identical parts. For clarity, not all reference numerals are used in every figure.

[0028] Figure 1A perspective view of a gear assembly 10 is shown, which has a gear 14 forming a main spindle nut 12. The main spindle nut 12 has a rotation axis 16 and teeth 18 rotating about the rotation axis 16, the teeth 18 having alternately arranged teeth 22 and tooth clearance 24 in a circumferential direction 20 about the rotation axis 16. The teeth 18 are designed here as external teeth. The main spindle nut 12 also has a through hole 28 formed along the rotation axis 16 for receiving a threaded spindle, the through hole 28 having threads 26. Figure 1 As shown, the gear assembly 10 includes a first stop plate 30 and a second stop plate 32.

[0029] Figure 4-6 A separate view of the spindle nut 12 is shown. It can be seen that the tooth 18 has a first end side 34 arranged axially and a second end side 36 arranged axially opposite to the first end side 34. The first end side 34 and the second end side 36 each have a groove 38 extending about the axis of rotation 16. Therefore, each tooth 22 may have a first portion 40 and a second portion 42 that is axially rearward relative to the first portion 40. The tooth 18 is defined radially outward by a head circle diameter 44 and radially inward by a root circle diameter 46 (see [link to original text]). Figure 6 ).from Figure 4 The diagram shows that the corresponding groove 38 is divided by the tooth gap 24.

[0030] in particular, Figure 4 and Figure 6 Each end face 34, 36 is shown to have an annular shoulder 48 that defines a corresponding groove 38 in the radial direction. The shoulder 48 has a shoulder diameter 49, which is configured to be smaller than the head circle diameter 44 and larger than the root circle diameter 46. Therefore, the shoulder 48 is divided by the tooth gap 24.

[0031] On both end sides 34, 36, shoulders 48 are configured to define radially inward grooves 38. Since the shoulders 48 define grooves 38 only radially inward, the corresponding first portion 40 of each tooth 22 is radially arranged within the corresponding second portion 42 of the tooth 22.

[0032] like Figure 6 As shown, the tooth 18 has a tooth height 50, and the shoulder 48 has a shoulder height 52, wherein the ratio of the shoulder height 52 to the tooth height 50 is 0.05 to 0.3, preferably 0.05 to 0.15. Figure 6 The schematic diagram also shows that, in the illustrated embodiment, tooth height 50 corresponds to the difference between head circle diameter 44 and root circle diameter 46, while shoulder height 52 corresponds to the difference between shoulder diameter 49 and root circle diameter 46.

[0033] Figure 7A separate view of the first stop plate 30 is shown. The first stop plate 30 and the second stop plate 32 are preferably designed with the same structure. Furthermore, from... Figure 1 and Figure 2 It can be seen that the first stop disc 30 and the second stop disc 32 each have a generally annular stop surface 54, and each has three disc protrusions 56 that protrude radially inward relative to the stop surface 54. In this case, the protruding free cutting surface 58 of the disc protrusions 56 radially cuts into the stop surface 54.

[0034] The first stop disc 30 is arranged in a groove 38 on the first end side 34 such that each disc protrusion 56 radially engages in a tooth gap 24. Therefore, the stop discs 30, 32 are arranged on the spindle nut 12 such that the disc protrusions 56 are supported on tooth sides radially adjacent to the corresponding grooves 38. Figure 3 As shown in the cross-sectional view, the disc protrusion 56 engages only radially in the corresponding tooth gap 24. From Figure 3 It can also be seen that the axial shoulder width 60 of the corresponding shoulder 48 is basically equal to the axial disc width 62 of the corresponding stop discs 30 and 32.

[0035] The spindle nut 12 and the stop discs 30 and 32 are connected by form-fitting only. In this case, the stop discs 30 and 32 may have radial and axial clearances relative to the spindle nut 12.

[0036] Each disc protrusion 56 has a protrusion profile 64 (see...) Figure 7 ).from Figure 2 As can be seen from the schematic diagram, the protrusion profile 64 is at least partially mathematically similar to the clearance profile 66 of each tooth gap 26. In this case, the protrusion profile 64 is similar to a portion of the clearance profile 66, i.e., the portion in which the corresponding disc protrusion 56 engages. In particular, the protrusion profile 64 is constructed to be similar in shape to the corresponding portion of the clearance profile 66, but compressed in the central direction. Therefore, a suitable clearance can be achieved between the stop discs 30, 32 and the spindle nut 12.

[0037] Especially Figure 1 , 3 As shown in Figures 4 and 6, radial bearing seats 68 are arranged axially adjacent to each other on both sides of the tooth portion 18 of the spindle nut 12. The radial bearing seats 68 are arranged axially adjacent to the tooth portion 18, and a corresponding free cutting surface 70 of the bearing seat is arranged between the tooth portion 18 and the radial bearing seat 68. The radial bearing seats 68 are cylindrical structures. The spindle nut 12 is an integral structure.

[0038] Figure 8A transmission device 72 for a longitudinal adjustment mechanism for a motor vehicle seat is shown. The transmission device 72 includes a transmission housing 74 and the aforementioned gear assembly 10. Figure 8 The diagram shows the through hole 28 of the spindle nut 12.

[0039] like Figure 9 As shown in the cross-sectional view, the transmission device 72 has two sliding bearings 76. Each sliding bearing 76 has an axial bearing portion 78 that abuts axially against the stop surface 54 of the corresponding stop discs 30, 32. Therefore, the axial force acting on the spindle nut 12 can be supported by the stop discs 30, 32 and the sliding bearings 76. For this purpose, the corresponding axial bearing portion 78 is arranged on the transmission device housing 74 by a bearing rear side 80 arranged axially relative to the stop surface 54.

[0040] Furthermore, each sliding bearing 76 has a radial bearing portion 82 disposed perpendicular to the axial bearing portion 78, wherein the corresponding radial bearing portion 82 is disposed abutting against one of the radial bearing seats 68. The axial inner diameter 84 of the axial bearing portion 78 is greater than or equal to the inner diameter 86 of the stop surface 54, and the axial outer diameter 88 of the axial bearing portion 78 is less than or equal to the outer diameter 90 of the stop surface 54.

[0041] The axial inner diameter 84 and axial outer diameter 88 preferably define the contact surface of the sliding bearing 76, which is used to contact the stop surface 54 of the stop discs 30 and 32. Figure 9 As shown, the sliding bearing 76 is L-shaped in the half-sectional view in each case. In this case, the radial bearing portion 82 and the axial bearing portion 78 are respectively adjacent to the chamfer 92 that connects the radial bearing portion 82 and the axial bearing portion 78.

[0042] List of reference numerals 10 Gear Assembly 12 Spindle Nut 14 Gears 16. Rotation axis 18 teeth 20 Circumferential direction 22 teeth 24 tooth gap 26 thread 28 through holes 30 First stop plate 32 Second stop plate 34 First end side 36 Second end side 38 grooves 40 Part 1 42 Part Two 44. Head diameter 46. ​​Root diameter 48 shoulder 49 shoulder diameter 50 tooth height 52 Shoulder height 54 Stop surface 56 disc protrusions 58. Protruding free cutting surface 60 shoulder width 62 Disk Width 64. Protruding outline 66 Gap Profile 68 Radial bearing housing 70 Bearing housing free-cutting surface 72 Transmission device 74 Transmission device housing 76 Sliding bearings 78 Axial bearing section 80 bearing rear side 82 Radial bearing section 84 Axial inner diameter 86 Stop surface inner diameter 88 Axial outer diameter 90 Outer diameter of the stop surface 92 chamfer

Claims

1. A gear assembly (10) comprising a gear (14) and at least one stop disc (30, 32) having a substantially annular stop surface (54), wherein, The gear (14) has a rotation axis (16) and teeth (18) arranged around the rotation axis (16). The teeth (18) have alternating teeth (22) and tooth gaps (24) in a circumferential direction (20) about the rotation axis (16). The teeth (18) have at least one axial end side (34, 36) with a groove (38) extending around the rotation axis (16). Its features are, The at least one stop disc (30, 32) has at least one disc protrusion (56) that protrudes radially relative to the stop surface (54) and is arranged in the groove (38) such that the at least one disc protrusion (56) radially engages in one of the tooth gaps (24).

2. The gear assembly (10) according to claim 1. Its features are, The at least one end side (34, 36) has at least one shoulder (48) that defines the groove (38) in the radial direction.

3. The gear assembly (10) according to claim 2. Its features are, The at least one shoulder (48) has a shoulder diameter (49), wherein the shoulder diameter (49) is configured to be smaller than the head circle diameter (44) of the tooth (18) and larger than the root circle diameter (46) of the tooth (18).

4. The gear assembly (10) according to any one of claims 2 to 3. Its features are, The at least one shoulder (48) is arranged to define the groove (38) radially inward and / or radially outward.

5. The gear assembly (10) according to any one of claims 2 to 4. Its features are, The tooth (18) has a tooth height (50), and the at least one shoulder (48) has a shoulder height (52), wherein the ratio of the shoulder height (52) to the tooth height (50) is 0.05 to 0.3, preferably 0.05 to 0.

15.

6. The gear assembly (10) according to any one of the preceding claims. Its features are, The gear (14) and the at least one stop disc (30, 32) interact and are connected only by form-locking.

7. The gear assembly (10) according to any one of the preceding claims. Its features are, The protrusion profile (64) of at least one disc protrusion (56) is at least partially mathematically similar to the gap profile (66) of one of the tooth gaps (24).

8. The gear assembly (10) according to any one of the preceding claims. Its features are, The at least one stop disc (30, 32) has a plurality of disc protrusions (56).

9. The gear assembly (10) according to any one of the preceding claims. Its features are, The gear (14) has at least one radial bearing seat (68) arranged axially adjacent to the tooth (18).

10. The gear assembly (10) according to any one of the preceding claims. Its features are, The gear (14) is configured as the spindle nut (12).

11. The gear assembly (10) according to any one of the preceding claims. Its features are, The first stop disc (30) of the at least one stop disc (30, 32) is arranged on the first end side (34) of the at least one end side (34, 36), and the second stop disc (32) of the at least one stop disc (30, 32) is arranged on the second end side (36) of the at least one end side (34, 36), wherein the second end side (36) is axially opposite to the first end side (34).

12. A transmission device (72), particularly an adjustment device for a motor vehicle, comprising a gear assembly (10) according to any one of the preceding claims.

13. The transmission device (72) according to claim 12. Its features are, The transmission device (72) has at least one sliding bearing (76), wherein the at least one sliding bearing (76) has an axial bearing portion (78) which is configured to abut the stop surface (54) of the at least one stop disc (30, 32) in the axial direction.

14. The transmission device (72) according to any one of claims 12 to 13, wherein, The gear assembly is constructed according to claim 9. Its features are, The at least one sliding bearing (76) has a radial bearing portion (82) perpendicular to the axial bearing portion (78), wherein the radial bearing portion (82) is configured to abut against the radial bearing housing (68), and wherein, The axial inner diameter (84) of the axial bearing portion (78) is greater than or equal to the inner diameter (86) of the stop surface (54), and / or The axial outer diameter (88) of the axial bearing portion (78) is less than or equal to the outer diameter (90) of the stop surface (54).

15. An adjustment device for a motor vehicle, particularly for a motor vehicle seat, comprising a transmission device (72) according to any one of claims 12 to 14.

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