Hub reduction gear and tractor

Abstract

The utility model provides a hub reduction gear and a tractor. The hub reduction gear is mainly applied to a tractor and comprises a knuckle shell, a first transmission shaft, a hub, an outer cover shell, a fixing shaft, an inner gear ring, a planetary gear, a limiting groove and a needle bearing, the limiting groove is formed in an inner ring of the planetary gear, the needle bearing comprises a bearing inner seat, a first needle roller, a second needle roller and a first clamping spring, the bearing inner seat is arranged on the fixing shaft in a sleeving mode, and the first clamping spring is arranged on the bearing inner seat. The first roller pin, the first clamp spring and the second roller pin are arranged in the circumferential direction of the bearing inner seat side by side in the axial direction of the bearing inner seat, and the first clamp spring is partially embedded in the limiting groove. According to the hub reduction gear, the needle bearing is arranged between the inner ring of the planetary gear and the fixing shaft as a whole, the first clamping spring is partially embedded in the limiting groove, the axial freedom degree of the needle bearing is completely limited and fixed, displacement does not exist between the first needle roller and the second needle roller, and the reliability of the hub reduction gear is improved.

Description

Technical Field

[0001] This utility model relates to the field of tractor technology, and in particular to a wheel-side reducer and a tractor. Background Technology

[0002] The wheel-side reducer mainly consists of a sun gear, planetary gears, a ring gear, and a planetary gear carrier. Its primary function is to reduce the speed and torque transmitted from the main reducer and then transmit it to the wheel, allowing the wheel to generate greater driving force under the reaction force of the ground adhesion. Simultaneously, it reduces the stress on the components in front of the wheel-side reducer, thus meeting the matching requirements of the entire transmission system. In existing technology, planetary gears are assembled onto the planetary carrier via planetary gear shafts, needle rollers, retaining rings, and bolts, and rotate around the planetary gear shafts. This results in a complex structure, cumbersome assembly, and large accumulated tolerances in the machining of parts. Therefore, it is necessary to provide a wheel-side reducer and tractor to overcome the aforementioned shortcomings. Utility Model Content

[0003] The purpose of this invention is to provide a wheel-side reducer and a tractor.

[0004] According to one aspect of the present invention, a wheel-side reducer and a tractor are provided, comprising: a steering knuckle housing; a first drive shaft, one end of which is disposed within the steering knuckle housing, and the other end of which is circumferentially provided with a toothed groove to form a sun gear shaft, the sun gear shaft passing through the steering knuckle housing to the outside of the steering knuckle housing; a hub, which is sleeved on the steering knuckle housing and rotatably connected to the steering knuckle housing; an outer cover, which is disposed on the side of the hub away from the steering knuckle housing; a fixed shaft, which is disposed inside the outer cover; and an internal gear ring, which is sleeved on the sun gear shaft. The upper part is fixed to the end of the steering knuckle housing; a planetary gear, which is sleeved on the fixed shaft and is evenly distributed between the internal gear ring and the sun gear shaft along the circumferential direction of the first transmission shaft; a limiting groove, which is provided on the inner ring of the planetary gear; a needle roller bearing, which includes a bearing inner seat, a first needle roller, a second needle roller and a first retaining ring, the bearing inner seat is sleeved on the fixed shaft, the first needle roller, the first retaining ring and the second needle roller are arranged side by side along the axial direction of the bearing inner seat in the circumferential direction of the bearing inner seat, and the first retaining ring is partially fitted into the limiting groove.

[0005] Preferably, the fixed shaft and the outer casing are an integral structure.

[0006] Preferably, the fixed shaft has a first step at the end near the outer casing and a first annular groove at the end away from the outer casing. A second retaining ring is provided on the first annular groove, and the bearing inner seat is located between the first step and the second retaining ring.

[0007] Preferably, the bearing inner seat is further provided with a boss portion, which is located between the first needle roller and the second needle roller, and the boss portion is aligned with the first retaining spring.

[0008] Preferably, the steering knuckle housing has a horizontal mounting hole in the middle, and the two ends of the mounting hole connect the inside of the outer cover and the inside of the steering knuckle housing. The sun gear shaft passes through the steering knuckle housing along the mounting hole to the outside of the steering knuckle housing.

[0009] Preferably, the end of the first drive shaft away from the outer casing is connected to the second drive shaft via a universal joint, and the second drive shaft is connected to the differential assembly.

[0010] Preferably, a bushing and a first oil seal are provided between the first drive shaft and the steering knuckle housing, a second step is provided inside the steering knuckle housing, the bushing is interference-fitted with the steering knuckle housing, and the first oil seal is located on one side of the bushing outer cover.

[0011] Preferably, the internal gear ring is fixed to the end of the steering knuckle housing by a gear ring seat, and a spacer ring is provided on the side of the internal gear ring near the outer cover. A locking ring and a third retaining ring are provided on the first drive shaft, and the spacer ring and the locking ring are clearance-fitted.

[0012] Preferably, the inner side of the outer casing is provided with a mounting part, and a limiting block is provided on the mounting part. A predetermined number and / or a predetermined thickness of shims are provided between the limiting block and the mounting part, so that the limiting block and the sun gear shaft maintain a predetermined gap.

[0013] According to another aspect of the present invention, a tractor is provided, including the aforementioned wheel-side reducer.

[0014] Compared with the prior art, the wheel-side reducer and tractor provided by this utility model have the following advantages: Due to the adoption of the above technical solution, this utility model has the advantages of simple structure, ingenious design and low cost. By setting the needle roller bearing as a whole between the inner ring of the planetary gear and the fixed shaft, and the first snap ring is partially fitted into the limiting groove, the axial degree of freedom of the needle roller bearing is completely restricted and fixed, and there is no movement between the first needle roller and the second needle roller, which improves the reliability of the wheel-side reducer. Attached Figure Description

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0016] Figure 1 This is a schematic diagram of the wheel-side reducer in this utility model;

[0017] Figure 2 The needle roller bearing in this utility model ( Figure 1 A magnified view of a portion of region A in the middle;

[0018] Figure 3 This is a schematic diagram of the structure of the needle roller bearing with a protective sleeve in this utility model;

[0019] Figure 4 The bushing in this utility model ( Figure 1 A magnified view of a portion of region B in the middle;

[0020] Figure 5 The limiting block in this utility model ( Figure 1 A magnified view of a portion of region C in the middle;

[0021] Figure 6 This is a schematic diagram of the drive axle in this utility model.

[0022] Explanation of reference numerals in the attached drawings: 100, wheel-side reducer; 200, differential assembly; 1, steering knuckle housing; 11, mounting hole; 12, spacer ring; 2, first drive shaft; 21, sun gear shaft; 22, bushing; 23, first oil seal; 24, locking ring; 25, third snap ring; 3, outer cover; 31, fixed shaft; 311, first step; 312, first ring groove; 313, second snap ring; 32, mounting part; 321 1. Limiting block; 322. Gasket; 4. Hub; 41. First bearing; 42. Second bearing; 43. Second oil seal; 5. Internal gear ring; 51. Gear ring seat; 52. Pin; 6. Planetary gear; 61. Limiting groove; 7. Needle roller bearing; 71. Bearing inner seat; 72. First needle roller; 73. Second needle roller; 74. First snap ring; 75. Protective sleeve; 711. Boss; 8. Universal joint; 9. Second drive shaft. Detailed Implementation

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] To keep the drawings concise, only the parts relevant to this invention are shown schematically in each figure, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of the components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."

[0025] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0026] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the specific implementation methods of this utility model will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of this utility model. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0029] See appendix Figures 1 to 6 This embodiment discloses a wheel-side reducer 100, which is mainly used in tractors. The wheel-side reducer 100 includes a steering knuckle housing 1, a first drive shaft 2, a wheel hub 4, and an outer cover 3.

[0030] The steering knuckle housing 1 is connected to the drive axle housing via a kingpin (not shown in the figure). A horizontal mounting hole 11 is provided in the middle of the steering knuckle housing 1 for the first drive shaft 2 to pass through. One end of the first drive shaft 2 is located inside the steering knuckle housing 1 and passes through the mounting hole 11. The two ends of the mounting hole 11 connect the interior of the outer casing 3 and the interior of the steering knuckle housing 1. The other end of the first drive shaft 2 has circumferentially toothed grooves forming a sun gear shaft 21. The sun gear shaft 21 passes through the mounting hole 11 to the outside of the steering knuckle housing 1.

[0031] The hub 4 is fitted onto the steering knuckle housing 1 and is rotatably connected to the steering knuckle housing 1 via a first bearing 41 and a second bearing 42. A second oil seal 43 is also provided between the hub 4 and the steering knuckle housing 1. The outer cover 3 is located on the side of the hub 4 away from the steering knuckle housing 1 and is fixed to the hub 4. The hub 4 and the outer cover 3 are fixed to form a receiving cavity.

[0032] See appendix Figure 1This embodiment uses a dry-field axle as an example. The end of the first drive shaft 2 furthest from the outer casing 3 is connected to the second drive shaft 9 via a universal joint 8. The second drive shaft 9 is connected to the differential assembly 200 to achieve power transmission. For a paddy-field axle, due to the height difference between the wheel hub 4 and the differential assembly 200, the end of the first drive shaft 2 furthest from the outer casing 3 can be connected to the second drive shaft 9 via a column and a bevel gear set. Of course, other types of front axles may have other connection and transmission methods, which will not be elaborated here.

[0033] In this embodiment, the fixed shaft 31 is located inside the outer casing 3, and there are three fixed shafts 31. The fixed shafts 31 and the outer casing 3 are an integral structure, forming a planetary carrier. The internal gear ring 5 is sleeved on the sun gear shaft 21 and fixed to the end of the steering knuckle housing 1. The planetary gears 6 are sleeved on the fixed shaft 31, and the planetary gears 6 are evenly distributed between the internal gear ring 5 and the sun gear shaft 21 along the circumferential direction of the first transmission shaft 2. The fixed shaft 31 is rotatably connected to the corresponding planetary gears 6.

[0034] Among them, the internal gear ring 5 is a fixed end. The rotation of the first transmission shaft 2 drives multiple planetary gears 6 to rotate synchronously, which in turn drives the planet carrier (i.e., the fixed shaft 31 and the outer cover 3) to rotate, which in turn drives the wheel hub 4 to rotate, thereby realizing the power output of the wheel-side reducer 100.

[0035] See appendix Figure 2 A roller bearing is provided between the inner ring of the planetary gear 6 and the sun gear shaft 21, and the planetary gear 6 is installed through the needle roller bearing 7. Specifically, a limiting groove 61 is provided on the inner ring of the planetary gear 6. The needle roller bearing 7 includes a bearing inner seat 71, a first needle roller 72, a second needle roller 73, and a first retaining ring 74. The bearing inner seat 71 is sleeved on the fixed shaft 31. The first needle roller 72, the first retaining ring 74, and the second needle roller 73 are arranged side by side along the axial direction of the bearing inner seat 71 in the circumferential direction of the bearing inner seat 71. The first retaining ring 74 is partially fitted into the limiting groove 61.

[0036] The fixed shaft 31 has a first step 311 at the end near the outer casing 3 and a first annular groove 312 at the end away from the outer casing 3. A second retaining ring 313 is provided on the first annular groove 312. The bearing inner seat 71 is located between the first step 311 and the second retaining ring 313. The bearing inner seat 71 also has a boss 711 located between the first needle roller 72 and the second needle roller 73. The boss 711 is aligned with the first retaining ring 74 to hold the first needle roller 72 and the second needle roller 73 in the bearing inner seat 71.

[0037] See appendix Figure 3 The image shows a needle roller bearing 7 with a protective sleeve 75 in an uninstalled state, where the first retaining ring 74 is not deployed due to the limiting effect of the protective sleeve 75.

[0038] During installation, the needle roller bearing 7 with protective sleeve 75 is aligned with the planetary gear 6. The needle roller bearing 7 is pushed into the annular gap formed between the inner ring of the planetary gear 6 and the sun gear shaft 21. When the needle roller bearing 7 abuts against the first step 311, the first retaining ring 74 moves to the limiting groove 61 and automatically opens, locking itself in the limiting groove 61. Finally, the second retaining ring 313 is locked in the first annular groove 312, so that the needle roller bearing 7 is located in the first step 311 and the second retaining ring 313, thus realizing the installation of the needle roller bearing 7.

[0039] See appendix Figure 4 A bushing 22 and a first oil seal 23 are provided between the first drive shaft 2 and the steering knuckle housing 1. The first rotating shaft is supported in the mounting hole 11 by the bushing 22 and the first oil seal 23, which improves the coaxiality of the assembly. A second step is provided inside the steering knuckle housing 1 for positioning. The bushing 22 is interference-fitted into the steering knuckle housing 1. The bushing 22 and the steering knuckle housing 1 are interference-fitted. The first oil seal 23 is located on one side of the outer cover 3 of the bushing 22. The first oil seal 23 is a combination oil seal.

[0040] The internal gear ring 5 is fixed to the end of the steering knuckle housing 1 via a gear ring seat 51 and a pin 52. A spacer ring 12 is provided on the side of the internal gear ring 51 closest to the outer housing 3. A locking ring 24 and a third retaining ring 25 are provided on the first drive shaft 2, with a clearance fit between the spacer ring 12 and the locking ring 24. When the sun gear shaft 21 moves axially away from the outer housing 3, the locking ring 24 abuts against the spacer ring 12, thus restricting and fixing the axial freedom of the first drive shaft 2, improving the reliability of the overall mechanism.

[0041] See appendix Figure 5 The inner side of the outer casing 3 is provided with a mounting part 32, and a limiting block 321 is provided on the mounting part 32. A shim 322 with adjustable thickness is provided between the limiting block 321 and the mounting part 32. Due to the accumulation of processing errors, the gap between the limiting block 321 and the end face of the first drive shaft 2 is not fixed. The predetermined number and predetermined thickness of the shim 322 are adjusted according to the specific actual situation so that the limiting block 321 and the sun gear shaft 21 maintain a predetermined gap. Preferably, the predetermined gap is 0.5mm, so as to avoid the first drive shaft 2 from axial movement and friction with the lip of the first oil seal 23, and reduce the failure rate of the wheel-side reducer 100.

[0042] It will be apparent to those skilled in the art that various modifications and variations can be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the present invention. Therefore, it is intended that the present invention cover modifications and variations falling within the scope of the appended claims and their equivalents.

Claims

1. A wheel-side reducer, characterized in that, include: Steering knuckle housing; A first drive shaft, one end of which is located inside the steering knuckle housing, and the other end of which is circumferentially provided with toothed grooves and forms a sun gear shaft, the sun gear shaft passing through the steering knuckle housing to the outside of the steering knuckle housing; A wheel hub, which is fitted onto the steering knuckle housing and rotatably connected to the steering knuckle housing; An outer casing, wherein the outer casing is located on the side of the wheel hub away from the steering knuckle housing; A fixed shaft is provided on the inner side of the outer casing; An internal gear ring, which is fitted onto the sun gear shaft and fixed to the end of the steering knuckle housing; Planetary gears are sleeved on the fixed shaft and are evenly distributed between the internal gear ring and the sun gear shaft along the circumferential direction of the first transmission shaft. A limiting groove is provided on the inner ring of the planetary gear; The needle roller bearing includes a bearing inner seat, a first needle roller, a second needle roller, and a first retaining ring. The bearing inner seat is sleeved on the fixed shaft. The first needle roller, the first retaining ring, and the second needle roller are arranged side by side along the axial direction of the bearing inner seat in the circumferential direction. The first retaining ring is partially fitted into the limiting groove.

2. The wheel-side reducer as described in claim 1, characterized in that, The fixed shaft and the outer casing are an integral structure.

3. The wheel-side reducer as described in claim 1, characterized in that, The fixed shaft has a first step at the end near the outer casing and a first annular groove at the end away from the outer casing. A second retaining ring is provided on the first annular groove, and the bearing inner seat is located between the first step and the second retaining ring.

4. The wheel-side reducer as described in claim 1, characterized in that, The bearing inner seat is also provided with a boss portion, which is located between the first needle roller and the second needle roller, and the boss portion is aligned with the first retaining spring.

5. The wheel-side reducer as described in claim 1, characterized in that, The steering knuckle housing has a horizontal mounting hole in the middle. The two ends of the mounting hole connect the inside of the outer cover and the inside of the steering knuckle housing. The sun gear shaft passes through the steering knuckle housing along the mounting hole to the outside of the steering knuckle housing.

6. The wheel-side reducer as described in claim 5, characterized in that, The end of the first drive shaft away from the outer casing is connected to the second drive shaft via a universal joint, and the second drive shaft is connected to the differential assembly.

7. The wheel-side reducer as described in claim 1, characterized in that, A bushing and a first oil seal are provided between the first drive shaft and the steering knuckle housing. A second step is provided inside the steering knuckle housing. The bushing is interference-fitted with the steering knuckle housing. The first oil seal is located on one side of the bushing outer cover.

8. The wheel-side reducer as described in claim 1, characterized in that, The internal gear ring is fixed to the end of the steering knuckle housing by a gear ring seat. A spacer ring is provided on the side of the internal gear ring near the outer cover. A locking ring and a third retaining ring are provided on the first drive shaft. The spacer ring and the locking ring are fitted with a clearance.

9. The wheel-side reducer as described in claim 8, characterized in that, The inner side of the outer casing is provided with a mounting part, and a limiting block is provided on the mounting part. A predetermined number and / or a predetermined thickness of shims are provided between the limiting block and the mounting part, so that the limiting block and the sun gear shaft maintain a predetermined gap.

10. A tractor, characterized in that, Includes the wheel-side reducer as described in any one of claims 1 to 9.

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