Wheel-side speed reduction structure

Abstract

The utility model provides a hub reduction structure which comprises a knuckle shell, a hub, a planetary transmission assembly, a gear ring seat and an inner gear ring, and the hub is connected with the knuckle shell through a first bearing assembly; the planetary transmission assembly comprises a planet carrier fixed to the end of the hub and a planet wheel arranged on the planet carrier. The gear ring seat is connected with the steering knuckle shell in a sleeving manner through a spline; the inner gear ring is arranged in the hub and meshed with the planet wheel, the inner gear ring is connected with the gear ring seat through a spline, a first step part which is concave outwards is arranged on the side, close to the steering knuckle shell, of an inner ring of the inner gear ring, and the gear ring seat is arranged in the first step part and abuts against the step face of the end of the first step part. The side, away from the steering knuckle shell, of the inner gear ring abuts against the planet carrier, axial limiting of the inner gear ring is achieved, parts are saved, assembling is easy, cost is reduced, and meanwhile the overall reliability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of tractor drive axles, in particular to a wheel-side speed reduction structure. Background Art

[0002] In the prior art, the existing front axle wheel reducer transmission structure is composed of a steering knuckle, a front wheel hub, a gear ring seat, an inner gear ring, a terminal universal joint shaft, a planetary gear, and a planetary frame. The power is transmitted from the terminal universal joint shaft to the wheel hub. The inner gear ring is fixed to the gear ring seat by a wire retaining ring, and the gear ring seat is fixed to the steering knuckle housing by bolts. The terminal universal joint shaft is free to rotate in the steering knuckle housing through a bushing. The axial movement of the terminal universal joint shaft is limited by the limit block on the planetary frame and the shaft elastic retaining ring. At the same time, a combined oil seal is installed on the terminal universal joint shaft for sealing. This structure often has poor coaxiality when the gear ring seat is fixed to the steering knuckle housing by bolts, resulting in an eccentric load on the planetary transmission mechanism, which in turn causes oil seal leakage. At the same time, this structure has many parts, is difficult to assemble, and has high requirements for the precision of parts.

[0003] Therefore, it is necessary to provide a wheel-side reduction structure to overcome the above-mentioned defects. Utility Model Content

[0004] The utility model aims to provide a wheel-side speed reduction structure.

[0005] According to one aspect of the utility model, a wheel-side reduction structure is provided, comprising:

[0006] A steering knuckle housing, wherein the steering knuckle housing is connected to an axle housing of a drive axle;

[0007] a wheel hub, the wheel hub being connected to the steering knuckle housing via a first bearing assembly;

[0008] A planetary transmission assembly, the planetary transmission assembly comprising a planet carrier fixed to an end of a wheel hub and a planetary wheel arranged on the planet carrier;

[0009] A gear ring seat, the gear ring seat is sleeve-connected to the steering knuckle housing via a spline;

[0010] An inner ring gear, the inner ring gear is arranged in the wheel hub and meshes with the planetary gear, the inner ring gear is connected to the ring gear seat through a spline, the inner ring of the inner ring gear is provided with a first step portion recessed outward on the side close to the steering knuckle housing, the ring gear seat is placed in the first step portion and abuts against the step surface at the end of the first step portion, and the inner ring gear is abutted against the planetary carrier on the side away from the steering knuckle housing to achieve axial limitation of the inner ring gear.

[0011] Preferably, it also includes a transmission shaft, one end of which passes through the steering knuckle housing and is connected to the drive shaft in the bridge housing through a universal joint, and the other end of the transmission shaft extends into the inner gear ring and is provided with a sun gear meshing with the planetary gear.

[0012] Preferably, the steering knuckle housing includes a connecting portion extending into the wheel hub and a cover housing portion located on the connecting portion away from the wheel hub and used to be connected to the bridge housing, the connecting portion is provided with a second step portion protruding radially outward, the gear ring seat is splined with the connecting portion, a spacer sleeve is provided between the gear ring seat and the second step portion, and the gear ring seat is abutted against the second step portion through the spacer sleeve.

[0013] Preferably, the connecting portion is connected to the wheel hub via a first bearing assembly, the connecting portion is connected to the transmission shaft via a second bearing assembly, and the transmission shaft is provided with a third step portion for supporting the second bearing assembly.

[0014] Preferably, the first bearing assembly includes a first tapered roller bearing and a second tapered roller bearing arranged between the wheel hub and the connecting portion, the inner ring end face of the first tapered roller bearing contacts the inner gear ring, the inner ring end face of the second tapered roller bearing contacts the side face of the cover shell portion, and the outer ring of the first tapered roller bearing and the outer ring of the second tapered roller bearing at opposite ends both contact the wheel hub.

[0015] Preferably, the second bearing assembly includes a third tapered roller bearing and a fourth tapered roller bearing arranged between the transmission shaft and the connecting portion, the inner ring end face of the third tapered roller bearing contacts with a retaining ring sleeved on the transmission shaft, the inner ring end face of the fourth tapered roller bearing contacts with the third step portion of the transmission shaft, and the outer ring of the third tapered roller bearing and the outer ring of the fourth tapered roller bearing have opposite ends that contact with the connecting portion.

[0016] Preferably, the planetary transmission assembly comprises a connecting shaft extending from the planet carrier to the inside of the wheel hub, and the planetary gear is rotatably connected to the connecting shaft.

[0017] Preferably, a first oil seal is provided at the connection between the cover portion and the wheel hub, the first oil seal is located on the outside of the second tapered roller bearing, a second oil seal is provided between the connecting portion and the transmission shaft, the second oil seal is located on the side of the fourth tapered roller bearing close to the universal joint.

[0018] Preferably, a limit block for abutting against the transmission shaft is provided on the inner surface of the planet carrier, and the axial movement of the transmission shaft is limited by the limit block and the retaining ring.

[0019] Preferably, the planet carrier comprises an annular boss extending into the wheel hub, and the inner gear ring is in abutment against the annular boss on a side away from the steering knuckle housing.

[0020] Compared with the prior art, the wheel-side reduction structure provided by the utility model has the following beneficial effects:

[0021] Due to the adoption of the above technical scheme, the utility model has the advantages of simple structure, ingenious design and low cost. The axial limitation of the inner ring gear and the ring gear seat is achieved through the annular boss, the inner ring gear, the inner ring gear seat, the retaining ring and the third step portion, which saves parts and components, simplifies assembly, reduces costs and improves overall reliability. The ring gear seat is connected to the steering knuckle housing sleeve by a spline, and the installation coaxiality of the inner ring gear is high, reducing the risk of oil leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The utility model is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0023] Figure 1 It is a structural schematic diagram of the wheel-side reduction structure of the utility model;

[0024] Figure 2 It is a three-dimensional diagram of the inner gear ring of the present utility model.

[0025] Among them, 1. bridge housing, 2. steering knuckle housing, 21. connecting part, 211. second step part, 22. cover part, 3. wheel hub, 4. planetary transmission assembly, 41. planet carrier, 411. limit block, 412. annular boss, 42. planetary gear, 43. connecting shaft, 5. gear ring seat, 6. inner gear ring, 61. first step part, 7. transmission shaft, 71. sun gear, 72. third step part, 8. first bearing assembly, 81. first tapered roller bearing, 82. second tapered roller bearing, 9. second bearing assembly, 91. third tapered roller bearing, 92. fourth tapered roller bearing, 101. spacer, 102. retaining ring, 103. first oil seal, 104. second oil seal, 105. universal joint, 106. drive shaft. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] In order to simplify the drawings, only the parts related to the utility model are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0028] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0029] In this article, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0030] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0031] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the specific implementation methods of the utility model will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0032] See also Figure 1 and Figure 2 The present embodiment discloses a wheel-side reduction structure, which is located on both sides of the drive axle and includes a steering knuckle housing 2, a wheel hub 3, a planetary transmission assembly 4, a gear ring seat 5 and an inner ring gear 6. The steering knuckle housing 2 is connected to the axle housing 1 of the drive axle, and the wheel hub 3 is connected to the steering knuckle housing 2 through a first bearing assembly 8. The planetary transmission assembly 4 includes a planet carrier 41 fixed to the end of the wheel hub 3 and a planetary wheel 42 arranged on the planet carrier 41. The gear ring seat 5 is sleeve-connected to the steering knuckle housing 2 through a spline. The inner ring gear 6 is arranged in the wheel hub 3 and connected to the gear ring seat 5 through a spline.

[0033] The planet carrier 41 includes a stopper 411 disposed in the middle of its inner surface and an annular boss 412 extending into the wheel hub. The stopper 411 and the annular boss 412 are coaxially arranged and both extend from the inner surface of the planet carrier 41 to the inside of the wheel hub 3. The annular boss 412 fits the inner surface of the wheel hub 3 and extends to the inside of the wheel hub 3, which further seals the connection between the planet carrier 41 and the wheel hub 3 to prevent water and dust. The planetary transmission assembly 4 also includes a plurality of connecting shafts 43 extending from the planet carrier 41 to the inside of the wheel hub 3. The connecting shafts 43 are arranged perpendicular to the planet carrier 41 and are circumferentially arranged around the stopper 411. The planetary gear 42 is sleeved on the end of the connecting shaft 43 and is rotatably connected to the connecting shaft 43.

[0034] The inner ring gear 6 meshes with the planetary gear 42 and is supported by the ring gear seat 5. The inner ring gear 6 is in contact with the annular boss 412 on one side near the planetary carrier 41. A first step portion 61 is provided on the inner ring of the inner ring gear 6 near the steering knuckle housing 2 and is recessed radially outward. The ring gear seat 5 is placed in the first step portion 61 and is in contact with the step surface at the end of the first step portion 61. The inner ring gear 6 is fixed by being in contact with the annular boss 412 and the ring gear seat 5 on both sides.

[0035] The knuckle housing 2 includes a connection portion 21 extending into the wheel hub 3 and a cover portion 22 located on the side of the connection portion 21 away from the wheel hub 3 and used to connect with the bridge housing 1. The connection portion 21 is provided with a second step portion 211 protruding radially outward. The ring gear seat 5 is sleeved on the connection portion 21 and splined with the connection portion 21. A spacer sleeve 101 is sleeved between the ring gear seat 5 and the second step portion 211, one side of the spacer sleeve 101 is abutted against the second step portion 211, and the other side of the spacer sleeve 101 is abutted against the ring gear seat 5. The ring gear seat 5 is abutted against the second step portion 211 through the spacer sleeve 101. Further, in this embodiment, one side of the inner ring gear 6 is abutted against the annular boss 412, and the other side is abutted against the second step portion 211 through the ring gear seat 5 and the spacer sleeve 101, so that the axial freedom of the inner ring gear 6 and the ring gear seat 5 is limited. At the same time, by selecting the spacer sleeves 101 of different thicknesses, the axial installation clearance between the inner gear ring 6 and the gear ring seat 5 can be adjusted to adapt to wheel-side reduction structures of different sizes.

[0036] The wheel-side reduction structure of this embodiment also includes a transmission shaft 7. One end of the transmission shaft 7 passes through the steering knuckle housing 2 and is connected to the drive shaft 106 in the bridge housing 1 through a universal joint, and the other end of the transmission shaft 7 extends into the inner gear ring 6 and abuts against the limit block 411, and is provided with a sun gear 71 meshing with the planetary gear 42.

[0037] The connecting portion 21 is connected to the wheel hub 3 through the first bearing assembly 8, and the connecting portion 21 is connected to the transmission shaft 7 through the second bearing assembly 9. The transmission shaft 7 is provided with a third step portion 72 for resisting the second bearing assembly 9. The first bearing assembly 8 includes a first tapered roller bearing 81 and a second tapered roller bearing 82 arranged between the wheel hub 3 and the connecting portion 21. Among them, the first tapered roller bearing 81 is sleeved on the gear ring seat 5, and its inner ring end face is in contact with the vertical surface of the gear ring seat 5. The second tapered roller bearing 9 is sleeved on the third step portion 72, and its inner ring end face is in contact with the side surface of the cover shell portion 22. The outer ring of the first tapered roller bearing 81 and the outer ring of the second tapered roller bearing 82 are in contact with the wheel hub 3 at opposite ends.

[0038] The second bearing assembly 9 includes a third tapered roller bearing 91 and a fourth tapered roller bearing 92 disposed between the transmission shaft 7 and the connecting portion 21. The inner ring end face of the third tapered roller bearing 91 contacts the retaining ring 102 sleeved on the transmission shaft 7, and the inner ring end face of the fourth tapered roller bearing 92 contacts the end face of the third step portion 72 of the transmission shaft 7. The outer ring of the third tapered roller bearing 91 and the outer ring of the fourth tapered roller bearing 92 are opposite to each other at one end and contact the connecting portion 21. The transmission shaft 7 is free to rotate in the steering knuckle housing 2 through the third tapered roller bearing 91 and the fourth tapered roller bearing 92, and is axially limited by the limit block 411 and the retaining ring 102.

[0039] A first oil seal 103 is provided at the connection between the housing portion 22 and the hub 3, and the first oil seal 103 is located outside the second tapered roller bearing 82. A second oil seal 104 is provided between the connection portion 21 and the transmission shaft 7, and the second oil seal 104 is located on the side of the fourth tapered roller bearing 92 close to the universal joint 105. Compared with the traditional structure, this structure reduces many parts, simplifies assembly, reduces costs, and the inner gear ring seat is positioned by splines, and the coaxiality of the inner gear ring is better than the existing solution, reducing the risk of oil leakage.

[0040] It will be apparent to those skilled in the art that various modifications and variations can be made to the above 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 covers modifications and variations of the present invention that fall within the scope of the appended claims and their equivalent technical solutions.

Claims

1. A wheel-side reduction structure, characterized in that: include: A steering knuckle housing, wherein the steering knuckle housing is connected to an axle housing of a drive axle; a wheel hub, the wheel hub being connected to the steering knuckle housing via a first bearing assembly; A planetary transmission assembly, the planetary transmission assembly comprising a planet carrier fixed to an end of a wheel hub and a planetary wheel arranged on the planet carrier; A gear ring seat, the gear ring seat is sleeve-connected to the steering knuckle housing via a spline; An inner ring gear, the inner ring gear is arranged in the wheel hub and meshes with the planetary gear, the inner ring gear is connected to the ring gear seat through a spline, the inner ring of the inner ring gear is provided with a first step portion recessed outward on the side close to the steering knuckle housing, the ring gear seat is placed in the first step portion and abuts against the step surface at the end of the first step portion, and the inner ring gear is abutted against the planetary carrier on the side away from the steering knuckle housing to achieve axial limitation of the inner ring gear.

2. The wheel-side reduction structure according to claim 1, characterized in that: It also includes a transmission shaft, one end of which passes through the steering knuckle housing and is connected to the drive shaft in the bridge housing through a universal joint, and the other end of the transmission shaft extends into the inner gear ring and is provided with a sun gear meshing with the planetary gear.

3. The wheel-side reduction structure according to claim 2, characterized in that: The steering knuckle housing includes a connecting portion extending into the wheel hub and a cover housing portion located on the connecting portion away from the wheel hub and used to connect with the bridge housing, the connecting portion is provided with a second step portion protruding radially outward, the gear ring seat is splined with the connecting portion, a spacer sleeve is sleeved between the gear ring seat and the second step portion, and the gear ring seat is abutted against the second step portion through the spacer sleeve.

4. The wheel-side reduction structure according to claim 3, characterized in that: The connecting portion is connected to the wheel hub via a first bearing assembly, and the connecting portion is connected to the transmission shaft via a second bearing assembly. The transmission shaft is provided with a third step portion for resisting the second bearing assembly.

5. The wheel-side reduction structure according to claim 4, characterized in that: The first bearing assembly includes a first tapered roller bearing and a second tapered roller bearing arranged between the wheel hub and the connecting portion, the inner ring end face of the first tapered roller bearing contacts the inner gear ring, the inner ring end face of the second tapered roller bearing contacts the side face of the cover shell portion, and the outer ring of the first tapered roller bearing and the outer ring of the second tapered roller bearing at opposite ends both contact the wheel hub.

6. The wheel-side reduction structure according to claim 5, characterized in that: The second bearing assembly includes a third tapered roller bearing and a fourth tapered roller bearing which are arranged between the transmission shaft and the connecting portion, the inner ring end face of the third tapered roller bearing contacts with a retaining ring sleeved on the transmission shaft, the inner ring end face of the fourth tapered roller bearing contacts with a third step portion of the transmission shaft, and the outer ring of the third tapered roller bearing and the outer ring of the fourth tapered roller bearing have opposite ends which contact with the connecting portion.

7. The wheel-side reduction structure according to claim 1, characterized in that: The planetary transmission assembly comprises a connecting shaft extending from the planet carrier to the inside of the wheel hub, and the planetary gear is rotatably connected to the connecting shaft.

8. The wheel-side reduction structure according to claim 6, characterized in that: A first oil seal is provided at the connection between the cover shell and the wheel hub, and the first oil seal is located on the outside of the second tapered roller bearing. A second oil seal is provided between the connection portion and the transmission shaft, and the second oil seal is located on the side of the fourth tapered roller bearing close to the universal joint.

9. The wheel-side reduction structure according to claim 8, characterized in that: The inner surface of the planet carrier is provided with a limit block for resisting the transmission shaft, and the axial movement of the transmission shaft is limited by the limit block and the retaining ring.

10. The wheel-side reduction structure according to claim 1, characterized in that: The planet carrier comprises an annular boss extending into the wheel hub, and the inner gear ring abuts against the annular boss at a side away from the steering knuckle housing.

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