Limited slip differential lock structure and drive axle

Abstract

The utility model discloses a limited slip differential lock structure and a drive axle, the limited slip differential lock structure is installed on the drive axle and comprises two half shafts and a differential mechanism; the differential mechanism is characterized in that the differential mechanism comprises a differential shell, two half axle gears, a planetary gear assembly and a friction plate assembly, the two half axle gears, the planetary gear assembly and the friction plate assembly are arranged in an inner cavity of the differential shell, the friction plate assembly comprises a first friction pair, and the first friction pair comprises a plurality of driving friction plates and a plurality of driven friction plates which surround a connecting shaft; the multiple driving friction plates are stacked to form a first friction plate set, the multiple driven friction plates are stacked to form a second friction plate set located on one side of the first friction plate set, and the driving friction plates and the driven friction plates are connected with the differential shell and the connecting shaft through splines respectively. Through the structural design, the internal friction torque of the differential mechanism is increased, the purpose of increasing the locking coefficient is achieved, and the slip limiting effect of the differential mechanism is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile accessories, in particular to a limited slip differential lock structure and a drive axle. Background Art

[0002] When the vehicle is driving in harsh conditions, the internal friction torque generated by the friction plate inside the differential is used to improve the vehicle's passability and prevent the wheels from slipping. The existing differential lock structure includes two half-axles, a differential case, and two half-axle gears installed in the inner cavity of the differential case, a planetary gear assembly, and a friction plate assembly. The differential case is connected to the inner ends of the two half-axles, and the outer end faces of the half-axle gears are formed with a connecting shaft. The planetary gear assembly is meshed with the two half-axle gears. The friction plate assembly includes multiple active friction plates and multiple driven friction plates. The multiple active friction plates and multiple driven friction plates are respectively connected to the differential case and the connecting shaft and are arranged at intervals. When the differential is locked, the active friction plate generates an internal friction torque by axially pressing the driven friction plate to complete the locking operation and realize the limited slip function. However, the limited slip effect of the above structure is poor, which is not conducive to the vehicle getting out of trouble. Utility Model Content

[0003] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a limited slip differential lock structure and a drive axle that improve the limited slip effect by stacking multiple active friction plates of a first friction pair into a first friction plate group and stacking multiple driven friction plates of the first friction pair into a second friction plate group.

[0004] To achieve the above purpose, the embodiment of the utility model adopts the following technical solutions:

[0005] The limited slip differential lock structure is installed on the drive axle and includes two half shafts and the differential;

[0006] The two half shafts are rotatably connected in the axle housing of the drive axle;

[0007] The differential includes a differential case surrounding the inner ends of the two half-shafts and two half-shaft gears, a planetary gear assembly and a friction plate assembly arranged in the inner cavity of the differential case, one of the half-shaft gears is connected to the inner end of the other half-shaft and its outer end surface forms a connecting shaft; the planetary gear assembly is located between the two half-shaft gears and meshes with the two half-shaft gears, and is rotatably connected to the differential case; the friction plate assembly includes a first friction pair, the first friction pair includes a plurality of active friction plates and a plurality of driven friction plates surrounding the outside of the connecting shaft, the plurality of active friction plates are stacked and form a first friction plate group, the plurality of driven friction plates are stacked and form a second friction plate group located on one side of the first friction plate group, and the active friction plates and the driven friction plates are respectively connected to the differential case and the connecting shaft through splines.

[0008] Furthermore, the first friction plate group is close to the inner end wall of the differential housing inner cavity relative to the second friction plate group, the first friction plate group has two fitted active friction plates, the second friction plate group is located on the inner side of the first friction plate group and has two fitted driven friction plates, and the driven friction plates can be tightly fitted with the active friction plates adjacent to them.

[0009] Furthermore, the friction plate assembly also includes a second friction pair located on the inner side of the first friction pair, the second friction pair includes a plurality of active friction plates and a plurality of driven friction plates surrounding the outside of the connecting shaft, the active friction plates and the driven friction plates of the second friction pair are arranged at intervals, and the active friction plates and the driven friction plates of the second friction pair are respectively connected to the differential housing and the connecting shaft through splines.

[0010] Further, a first adjustment gasket is provided between the outer end surface of the friction plate assembly and the inner end wall of the corresponding differential housing inner cavity; and / or,

[0011] A second adjusting gasket is provided between the inner end surface of the friction plate assembly and the outer end surface of the corresponding side gear;

[0012] The first adjusting gasket and the second adjusting gasket are sleeved on the connecting shaft and have gaps with the inner walls of the differential housing inner cavity respectively so as to be disconnected from the differential housing.

[0013] Furthermore, the inner end of the friction plate assembly is provided with the first friction plate group close to the inner end wall, the outer end surface of the active friction plate of the first friction plate group forms the outer end surface of the friction plate assembly, and the first adjusting gasket is fitted with the outer end surface of the active friction plate; the outer end of the friction plate assembly is provided with the driven friction plate close to the outer end surface of the half-shaft gear, the inner end surface of the driven friction plate forms the inner end surface of the friction plate assembly, and the second adjusting gasket is fitted with the inner end surface of the driven friction plate.

[0014] Furthermore, the two inner end walls of the differential housing cavity are respectively concavely formed outwardly to form an annular groove corresponding to the outer end surface of the connecting shaft of each half-shaft gear, and a thrust washer is fitted in each of the grooves, and the thrust washer is sleeved on the inner end of the half-shaft.

[0015] Furthermore, there is a gap between the thrust washer and the outer end surface of the connecting shaft, and the outer diameter of the thrust washer is smaller than or equal to the outer diameter of the connecting shaft.

[0016] Furthermore, the differential case has two half shells, the inner end surfaces of the two half shells are butt-jointed and fixed by bolts, and one of the half shells is wrapped around the inner end of one of the half shafts; the half shaft gear is connected to the inner end of the half shaft by a spline, and the friction plate assembly has two groups, one group of the friction plate assemblies is wrapped around the outside of one of the connecting shafts, and the inner end surface of the driven friction plate is provided with friction material.

[0017] The friction plate assembly of the limited slip differential lock structure of the utility model increases the internal friction torque of the differential by stacking multiple active friction plates of the first friction pair into a first friction plate group and stacking multiple driven friction plates of the first friction pair into a second friction plate group, thereby increasing the locking coefficient and improving the limited slip effect of the differential. The limited slip differential lock structure of the utility model is simple and has a long service life.

[0018] An embodiment of the utility model further provides a drive axle, comprising the limited slip differential lock structure described in any of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a cross-sectional view of the limited slip differential lock structure of an embodiment of the utility model;

[0020] Figure 2 for Figure 1 A partial schematic diagram of

[0021] Figure 3 for Figure 2 A magnified view of the local area A;

[0022] Figure 4 for Figure 2 Schematic diagram of local three-dimensional decomposition. DETAILED DESCRIPTION

[0023] Below, in conjunction with the accompanying drawings and specific implementation methods, the utility model is further described:

[0024] like Figures 1 to 4 As shown, an embodiment of the utility model provides a limited slip differential lock structure, which is installed on a wet drive axle of a forklift truck, and includes two half shafts 1 and a differential 2, and the differential 2 is connected to the two half shafts 1.

[0025] like Figure 1 , Figure 2 As shown, the two half shafts 1 are rotatably connected to the axle housing 100 of the drive axle, and the ends of the two half shafts 1 that are close to each other are the inner ends. The differential 2 includes a differential housing 21 surrounding the inner ends 11 of the two half shafts, and two half shaft gears 22, a planetary gear assembly 23 and a friction plate assembly 24 arranged in the inner cavity 211 of the differential housing. The outer peripheral walls at both ends of the differential housing 21 are matched with the inner cavity of the axle housing 100 through bearings. Specifically, the differential housing 21 has two half shells 212, and the inner end surfaces of the two half shells 212 are connected and fixed by bolts (such as Figure 4 As shown in FIG. 1 , a half shell 212 surrounds the inner end of the half shaft 1. A half shaft gear 22 is connected to the inner end 11 of the half shaft to rotate synchronously with the half shaft 1 and its outer end surface extends outward to form a connecting shaft 221. Specifically, the half shaft gear 22 is connected to the inner end 11 of the half shaft through a spline. The planetary gear assembly 23 is located between the two half shaft gears 22 and its planetary gear 231 is meshed with the two half shaft gears 22, and the planetary gear 231 is rotationally connected to the differential housing 21 through a cross shaft.

[0026] like Figures 1 to 3 As shown, there are two groups of friction plate assemblies 24, one group of friction plate assemblies 24 surrounds the outside of a connecting shaft 221. The friction plate assembly 24 includes a first friction pair 241, and the first friction pair 241 includes a plurality of active friction plates 2411 and a plurality of driven friction plates 2412 surrounding the outside of the connecting shaft 221. The plurality of active friction plates 2411 are stacked and form a first friction plate group, and the plurality of driven friction plates 2412 are stacked and form a second friction plate group located on one side of the first friction plate group. The active friction plates 2411 and the driven friction plates 2412 are respectively connected to the differential housing 21 and the connecting shaft 221 through splines, and the inner end surface of the driven friction plate 2412 is provided with friction material, which can enable the friction plate assembly 24 to generate internal friction torque when the differential 2 is locked. By stacking the multiple active friction plates 2411 of the first friction pair 241 into a first friction plate group and stacking the multiple driven friction plates 2412 of the first friction pair 241 into a second friction plate group, the internal friction torque of the differential 2 is increased, thereby achieving the purpose of increasing the locking coefficient, thereby improving the limited slip effect of the differential 2, and the structure is simple and easy to install.

[0027] like Figure 2 , Figure 3As shown, in this embodiment, the first friction plate group is close to the inner end wall 2111 of the differential housing cavity 211 relative to the second friction plate group. The first friction plate group has two fitted active friction plates 2411. The second friction plate group is located on the inner side of the first friction plate group and has two fitted driven friction plates 2412. The driven friction plates 2412 can be tightly fitted with the adjacent active friction plates 2411 to realize the locking function of the differential 2. Since the locking coefficient is related to the number of active friction plates 2411 and driven friction plates 2412 of the first friction plate group, when the locking coefficient needs to be reduced, the number of active friction plates 2411 and driven friction plates 2412 of the first friction plate group is increased to reduce the number of friction pairs; when the locking coefficient needs to be increased, the number of active friction plates 2411 and driven friction plates 2412 of the first friction plate group is reduced to increase the number of friction pairs; therefore, in other embodiments, when the locking coefficient needs to be reduced, the number of active friction plates 2411 and driven friction plates 2412 of the first friction plate group is set to be greater than or equal to 3 respectively. It can be seen that the number of active friction plates 2411 and driven friction plates 2412 of the first friction plate group can be selected according to the actual requirements of the locking coefficient.

[0028] like Figure 2 , Figure 3 As shown, in this embodiment, the friction plate assembly 24 further includes a second friction pair 242 located inside the first friction pair 241, and the second friction pair 242 includes a plurality of active friction plates 2411 and a plurality of driven friction plates 2412 surrounding the outside of the connecting shaft 221, and the active friction plates 2411 and the driven friction plates 2412 of the second friction pair 242 are arranged at intervals, and the active friction plates 2411 and the driven friction plates 2412 of the second friction pair 242 are connected to the differential housing 21 and the connecting shaft 221 respectively through splines. In another embodiment, the second friction pair 242 may not be provided, but multiple groups of first friction plate groups and multiple groups of second friction plate groups may be provided, and the first friction plate group and the second friction plate group may be arranged at intervals.

[0029] like Figure 2 , Figure 3As shown, in order to extend the service life of the limited slip differential 2 structure, in an optional embodiment, a first adjustment gasket 243 is provided between the outer end surface of the friction plate assembly 24 and the inner end wall 2111 of the corresponding differential housing inner cavity 211, or a second adjustment gasket 244 is provided between the inner end surface of the friction plate assembly 24 and the outer end surface of the corresponding side gear 22. In this embodiment, a first adjustment gasket 243 is provided between the outer end surface of the friction plate assembly 24 and the inner end wall 2111 corresponding thereto, and a second adjustment gasket 244 is provided between the inner end surface of the friction plate assembly 24 and the outer end surface of the corresponding side gear 22. The first adjustment gasket 243 and the second adjustment gasket 244 are sleeved on the connecting shaft 221 and have gaps with the inner walls of the differential housing inner cavity 211 respectively to disconnect them from the differential housing 21, wherein the first adjustment gasket 243 and the second adjustment gasket 244 have the same structure; specifically, The inner end of the friction plate assembly 24 is provided with a first friction plate group close to the inner end wall 2111, the outer end surface of the active friction plate 2411 of the first friction plate group forms the outer end surface of the friction plate assembly 24, and the first adjusting gasket 243 is fitted with the outer end surface of the active friction plate 2411; the outer end of the friction plate assembly 24 is provided with a driven friction plate 2412 close to the outer end surface of the half-shaft gear 22, the inner end surface of the driven friction plate 2412 forms the inner end surface of the friction plate assembly 24, and the second adjusting gasket 244 is fitted with the inner end surface of the driven friction plate 2412. By setting the first adjusting gasket 243 and the second adjusting gasket 244, while ensuring that the tooth side clearance between the planetary gear 231 of the planetary gear assembly 23 and the half-shaft gear 22 meets the conditions, the active friction plate 2411, the first adjusting gasket 243, the second adjusting gasket 244 and the end face of the half-shaft gear 22 are prevented from rotating relative to each other when the internal friction torque is generated in the differential 2, so as to avoid premature wear and tooth failure, thereby extending the service life.

[0030] like Figure 2 , Figure 3 As shown, in order to further extend the service life of the limited slip differential 2 structure, two inner end walls 2111 of the differential housing cavity 211 are respectively concavely formed with an annular clamping groove 2112 corresponding to the outer end surface of the connecting shaft 221 of each half-shaft gear 22, and each clamping groove 2112 is matched with a thrust washer 2113, and the thrust washer 2113 is sleeved on the inner end 11 of the half-shaft 1. Specifically, there is a gap between the thrust washer 2113 and the outer end surface of the connecting shaft 221, and its outer diameter is less than or equal to the outer diameter of the connecting shaft 221 to provide a clearance space for other parts of the limited slip differential 2. By setting the thrust washer 2113, after the vehicle is used for a long time, and when the driven friction plate 2412 is worn to a certain extent, the thrust washer 2113 is put into operation, thereby avoiding the situation of tooth failure caused by excessive tooth side clearance between the planetary gear 231 and the half-shaft gear 22 due to the wear of the driven friction plate 2412, and further extending the service life.

[0031] The friction plate assembly of the limited slip differential lock structure of the utility model increases the internal friction torque of the differential by stacking multiple active friction plates of the first friction pair into a first friction plate group and stacking multiple driven friction plates of the first friction pair into a second friction plate group, thereby increasing the locking coefficient and improving the limited slip effect of the differential. The limited slip differential lock structure of the utility model is simple and has a long service life.

[0032] The utility model further provides a drive axle, comprising the limited slip differential lock structure described in any one of the above embodiments. In this embodiment, the drive axle is a wet drive axle of a forklift truck.

[0033] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein, and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. Limited slip differential lock structure, installed on the drive axle, characterized by: Includes two half shafts and differential; The two half shafts are rotatably connected in the axle housing of the drive axle; The differential includes a differential case surrounding the inner ends of the two half-shafts and two half-shaft gears, a planetary gear assembly and a friction plate assembly arranged in the inner cavity of the differential case, one of the half-shaft gears is connected to the inner end of the other half-shaft and its outer end surface forms a connecting shaft; the planetary gear assembly is located between the two half-shaft gears and meshes with the two half-shaft gears, and is rotatably connected to the differential case; the friction plate assembly includes a first friction pair, the first friction pair includes a plurality of active friction plates and a plurality of driven friction plates surrounding the outside of the connecting shaft, the plurality of active friction plates are stacked and form a first friction plate group, the plurality of driven friction plates are stacked and form a second friction plate group located on one side of the first friction plate group, and the active friction plates and the driven friction plates are respectively connected to the differential case and the connecting shaft through splines.

2. The limited slip differential lock structure according to claim 1, characterized in that: The first friction plate group is closer to the inner end wall of the differential housing inner cavity relative to the second friction plate group. The first friction plate group has two fitted active friction plates. The second friction plate group is located on the inner side of the first friction plate group and has two fitted driven friction plates. The driven friction plates can be tightly fitted with the adjacent active friction plates.

3. The limited slip differential lock structure according to claim 1, characterized in that: The friction plate assembly also includes a second friction pair located on the inner side of the first friction pair, the second friction pair includes a plurality of active friction plates and a plurality of driven friction plates surrounding the outside of the connecting shaft, the active friction plates and the driven friction plates of the second friction pair are arranged at intervals, and the active friction plates and the driven friction plates of the second friction pair are respectively connected to the differential housing and the connecting shaft through splines.

4. The limited slip differential lock structure according to claim 1, characterized in that: A first adjustment gasket is provided between the outer end surface of the friction plate assembly and the inner end wall of the corresponding differential housing inner cavity; and / or, A second adjusting gasket is provided between the inner end surface of the friction plate assembly and the outer end surface of the corresponding side gear; The first adjusting gasket and the second adjusting gasket are sleeved on the connecting shaft and have gaps with the inner walls of the differential housing inner cavity respectively so as to be disconnected from the differential housing.

5. The limited slip differential lock structure according to claim 4, characterized in that: The inner end of the friction plate assembly is provided with the first friction plate group close to the inner end wall, the outer end surface of the active friction plate of the first friction plate group forms the outer end surface of the friction plate assembly, and the first adjusting gasket is fitted with the outer end surface of the active friction plate; the outer end of the friction plate assembly is provided with the driven friction plate close to the outer end surface of the half-shaft gear, the inner end surface of the driven friction plate forms the inner end surface of the friction plate assembly, and the second adjusting gasket is fitted with the inner end surface of the driven friction plate.

6. The limited slip differential lock structure according to claim 1, characterized in that: The two inner end walls of the differential housing cavity correspond to the outer end surface of the connecting shaft of each half-shaft gear and are concave outward to form an annular groove. A thrust washer is fitted in each groove, and the thrust washer is sleeved on the inner end of the half-shaft.

7. The limited slip differential lock structure according to claim 6, characterized in that: There is a gap between the thrust washer and the outer end surface of the connecting shaft, and the outer diameter of the thrust washer is smaller than or equal to the outer diameter of the connecting shaft.

8. The limited slip differential lock structure according to claim 1, characterized in that: The differential case has two half shells, the inner end surfaces of the two half shells are butted against each other and fixed by bolts, and one of the half shells is wrapped around the inner end of one of the half shafts; the half shaft gear is connected to the inner end of the half shaft through a spline, and the friction plate assembly has two groups, one group of the friction plate assemblies is wrapped around the outside of one of the connecting shafts, and the inner end surface of the driven friction plate is provided with friction material.

9. Drive axle, characterized in that: It comprises the limited slip differential lock structure as claimed in any one of claims 1 to 8.

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