Differential lubricating structure

Abstract

The differential lubricating structure comprises an outer shell, a half axle gear, a planetary pin shaft and a planetary gear, the planetary pin shaft is installed in the outer shell in the radial direction, the planetary gear is connected with the planetary pin shaft in a matched mode, the half axle gear is installed in the outer shell in the axial direction, and the half axle gear is meshed with the planetary gear; a first oil inlet hole is formed in the end part of the outer shell, a radial oil channel is formed in the planetary pin shaft, an axial oil hole communicated with the radial oil channel is formed in the side part of the planetary pin shaft, and the radial oil channel is communicated with the first oil inlet hole through an elastic pin shaft; lubricating oil enters the radial oil channel through the first oil inlet hole and the elastic pin shaft and flows to the matching face of the planetary pin shaft and the planetary gear through the axial oil hole. The differential mechanism has the advantages of being compact in structure, good in lubricating effect, high in stability and the like, and the failure risks of planet pin shaft ablation, turning abnormal sound and the like of the differential mechanism are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to a differential lubrication structure. Background Art

[0002] The differential regulates the speeds of the left and right wheels in a vehicle's powertrain, allowing the drive wheels to rotate at different speeds when the vehicle turns. Its function necessitates the transmission of complex and demanding motion and power by its subcomponents. When a differential occurs, friction occurs between the axle shafts and the outer housing, between the planetary gears and the planetary pins, between the planetary gear spacers and the outer housing, and between the axle shaft gear spacers and the outer housing. The friction pair between the planetary gears and the planetary pins, in particular, often heats up due to insufficient lubrication due to the high loads and high speed differentials, leading to high-temperature erosion and failure of the planetary pins. Furthermore, insufficient lubrication between the planetary gears and the planetary shafts during slow turns can cause abnormal low-speed cornering noise, a common form of differential failure.

[0003] In existing differential lubrication systems, the rotation of the differential drives the oil, which splashes into the space between the planetary gears and the planetary pins. This results in low oil transfer efficiency and limited oil volume. When extreme differential conditions occur, insufficient lubrication can cause the mating friction pairs to heat up, leading to planetary pins eroding and breaking, resulting in vehicle power interruption and other failures. Furthermore, in existing systems, the differential lubrication is slow during low-speed cornering, making it difficult for the oil to effectively penetrate the mating surfaces. This prevents the oil film from forming, and can easily cause dry friction between the planetary gears and the planetary pins, resulting in abnormal cornering noise. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a differential lubrication structure with compact structure, good lubrication effect and high stability in response to the above-mentioned problems in the prior art.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A differential lubrication structure includes an outer shell, a half-shaft gear, a planetary pin shaft and a planetary gear, wherein the planetary pin shaft is radially mounted inside the outer shell, the planetary gear is cooperatively connected to the planetary pin shaft, the half-shaft gear is axially mounted inside the outer shell, and the half-shaft gear is meshed with the planetary gear; a first oil inlet hole is provided at the end of the outer shell, a radial oil passage is provided inside the planetary pin shaft, an axial oil hole is provided on the side of the planetary pin shaft that passes through the radial oil passage, and the radial oil passage is connected to the first oil inlet hole through an elastic pin shaft; lubricating oil enters the radial oil passage through the first oil inlet hole and the elastic pin shaft, and flows to the mating surface of the planetary pin shaft and the planetary gear through the axial oil hole.

[0007] As a further improvement of the present invention, a detachable sealing plug is provided on the planetary pin shaft to seal the end of the axial oil hole.

[0008] As a further improvement of the present invention, a radial oil guide hole is provided on the side of the elastic pin shaft, and the lubricating oil entering the elastic pin shaft through the first oil inlet hole flows into the axial oil hole through the oil guide hole.

[0009] As a further improvement of the present invention, a second oil inlet hole is further provided at the end of the outer shell, and the first oil inlet hole and the second oil inlet hole are symmetrically arranged at both ends of the outer shell, and the oil inlet directions of the first oil inlet hole and the second oil inlet hole are opposite, and the first oil inlet hole and the second oil inlet hole are respectively connected to the two ends of the axial oil hole to realize the simultaneous introduction of lubricating oil at both ends of the axial oil hole.

[0010] As a further improvement of the present invention, the axial oil holes on both sides of the radial oil passage are arranged in groups of two and are provided on the matching surfaces of the planetary pins and the planetary gears.

[0011] As a further improvement of the present invention, axial mounting holes communicating with the radial oil passage are symmetrically provided at both ends of the planetary pin shaft, and the axial mounting holes are used for mounting the elastic pin shaft.

[0012] As a further improvement of the present invention, radial mounting holes are symmetrically provided at both ends of the planetary pin shaft, and the radial mounting holes are located inside the axial mounting hole for connecting the planetary gears.

[0013] As a further improvement of the present invention, a gasket is provided between the inner wall of the outer shell and the planetary gear.

[0014] Compared with the prior art, the advantages of the present invention are:

[0015] The differential lubrication structure of the present invention is characterized in that the planetary pin is radially installed inside the outer shell, the planetary gear is matched with the planetary pin, the half-shaft gear is axially installed inside the outer shell, and the half-shaft gear is meshed with the planetary gear, thus forming a compact differential lubrication structure body; further, a first oil inlet hole is provided at the end of the outer shell, a radial oil passage is provided inside the planetary pin, and an axial oil hole that passes through the radial oil passage is provided on the side of the planetary pin, and the radial oil passage is connected to the first oil inlet hole through the elastic pin, thereby realizing the connection of the planetary pin with an external lubricating oil supply source; during the operation of the differential, the lubricating oil enters the radial oil passage through the first oil inlet hole and the elastic pin, and then flows to the mating surface of the planetary pin and the planetary gear through the axial oil hole, ensuring that a stable oil film is established on the mating surface, reducing the risk of failure of the differential such as planetary pin ablation and abnormal turning noise, ensuring the lubrication of each friction pair inside the differential, and taking into account the flow rate of the lubricating oil and the working efficiency of the reducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structural principle of a differential lubrication structure in a specific embodiment of the present invention;

[0017] Figure 2 A schematic diagram of the structural principle of the differential lubrication structure in another embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the structural principle of the elastic pin in a specific embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of the structural principle of a star-shaped pin shaft in a specific embodiment of the present invention;

[0020] Legend: 1. Outer casing; 2. Axle gear; 4. Elastic pin; 5. Planetary pin; 6. Gasket; 7. Planetary gear; 8. Sealing plug; 11. First oil inlet hole; 12. Second oil inlet hole; 41. Oil guide hole; 51. Axial oil hole; 52. Radial oil channel; 53. Axial mounting hole; 54. Radial mounting hole. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the scope of protection of the present invention is not limited thereby.

[0022] In the description of the present invention, it should be understood that the terms "side", "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0024] Example

[0025] like Figures 1 to 4As shown, the differential lubrication structure of the present invention comprises an outer housing 1, side gears 2, planetary pins 5, and planetary gears 7. The planetary pins 5 are radially mounted within the outer housing 1, and the planetary gears 7 are matingly connected to the planetary pins 5. A gasket 6 is provided between the inner wall of the outer housing 1 and the planetary gears 7. The side gears 2 are axially mounted within the outer housing 1 and mesh with the planetary gears 7. A first oil inlet 11 is provided at the end of the outer housing 1. A radial oil passage 52 is provided within the planetary pins 5. An axial oil hole 51 is provided on the side of the planetary pins 5, extending through the radial oil passage 52. The radial oil passage 52 is connected to the first oil inlet 11 via the elastic pin 4. The first oil inlet 11 not only guides oil but also serves as a mounting hole for the elastic pin 4, radially positioning the planetary pin 5. Lubricating oil enters the radial oil passage 52 through the first oil inlet 11 and the elastic pin 4, and flows through the axial oil hole 51 to the mating surface between the planetary pin 5 and the planetary gear 7, providing lubrication and cooling. It can be seen that a gear gasket is provided between the side gear 2 and the outer shell 1 . The specific structure of the side gear 2 adopts the conventional setting in this field and will not be described in detail here.

[0026] In this embodiment, a compact differential lubrication structure is formed by radially mounting the planetary pins 5 within the outer housing 1, matingly connecting the planetary gears 7 to the planetary pins 5, and axially mounting the side gears 2 within the outer housing 1, where the side gears 2 mesh with the planetary gears 7. Furthermore, a first oil inlet 11 is provided at the end of the outer housing 1, radial oil passages 52 are provided within the planetary pins 5, and axial oil holes 51 are provided on the sides of the planetary pins 5, extending through the radial oil passages 52. The radial oil passages 52 communicate with the first oil inlet 11 via the elastic pins 4, thereby connecting the planetary pins 5 to an external lubricating oil supply. During the operation of the differential, the lubricating oil enters the radial oil channel 52 through the first oil inlet hole 11 and the elastic pin 4, and then flows to the mating surface of the planetary pin 5 and the planetary gear 7 through the axial oil hole 51. The lubricating oil can more easily enter the mating surface between the planetary gear 7 and the planetary pin 5, ensuring that a stable oil film is established on the mating surface, reducing the risk of failure of the differential such as erosion of the planetary pin 5 and abnormal noise during cornering, ensuring the lubrication of the friction pairs inside the differential, and taking into account the flow rate of the lubricating oil and the working efficiency of the reducer.

[0027] like Figure 1 and Figure 2 As shown, one end of the planetary pin 5 is a closed structure and the other end is an open structure. A detachable sealing plug 8 is provided at the open end of the planetary pin 5 to seal the end of the axial oil hole 51 to prevent the lubricating oil in the axial oil hole 51 from leaking out.

[0028] like Figure 3As shown, a radial oil guide hole 41 is provided on the side of the elastic pin 4. Lubricating oil entering the interior of the elastic pin 4 through the first oil inlet hole 11 flows through the oil guide hole 41 into the axial oil hole 51. The elastic pin 4 also has a long strip opening on the side. When the elastic pin 4 is installed and secured, this long strip opening faces the end of the axial oil hole 51. If the oil guide hole 41 becomes blocked, the lubricating oil entering the elastic pin 4 can overflow from the long strip opening and flow into the axial oil hole 51.

[0029] like Figure 1 As shown, a second oil inlet hole 12 is further provided at the end of the outer shell 1, and the first oil inlet hole 11 and the second oil inlet hole 12 are symmetrically arranged at both ends of the outer shell 1, and the oil inlet directions of the first oil inlet hole 11 and the second oil inlet hole 12 are opposite. The first oil inlet hole 11 and the second oil inlet hole 12 are respectively connected to the two ends of the axial oil hole 51 to achieve the simultaneous introduction of lubricating oil into both ends of the axial oil hole 51.

[0030] like Figure 1 As shown in FIG, the first oil inlet hole 11 and the second oil inlet hole 12 are both blind holes. By providing an elastic pin 4 in the first oil inlet hole 11, the planetary pin 5 can be positioned radially. In other embodiments, an elastic pin 4 can also be provided in the second oil inlet hole 12 to improve the accuracy of radial positioning of the planetary pin 5 inside the outer shell 1.

[0031] like Figure 1 and Figure 4 As shown, the axial oil holes 51 on both sides of the radial oil passage 52 are arranged in groups of two on the mating surfaces of the planetary pin 5 and the planetary gear 7. Specifically, two groups of axial oil holes 51 are provided on the upper mating surfaces of the planetary pin 5 and the planetary gear 7, and two groups of axial oil holes 51 are also provided on the lower mating surfaces of the planetary pin 5 and the planetary gear 7.

[0032] like Figure 4 As shown, axial mounting holes 53 that penetrate the radial oil passage 52 are symmetrically provided at both ends of the planetary pin 5 . The axial mounting holes 53 are close to the ends of the planetary pin 5 and are used to mount the elastic pin 4 .

[0033] like Figure 4 As shown, radial mounting holes 54 are symmetrically provided at both ends of the planetary pin 5 for connecting to the planetary gears 7. On the planetary pin 5, the radial mounting holes 54 are not connected to the radial oil passages 52. The radial mounting holes 54 are located inside the axial mounting holes 53, and the axial oil holes 51 are located inside the radial mounting holes 54. This allows the lubricating oil in the axial oil holes 51 to flow to the mating surfaces of the planetary pin 5 and the planetary gears 7 for lubrication and cooling.

[0034] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A differential lubrication structure, characterized in that: The invention comprises an outer shell (1), a half-shaft gear (2), a planetary pin shaft (5) and a planetary gear (7); the planetary pin shaft (5) is radially mounted inside the outer shell (1); the planetary gear (7) is matched and connected with the planetary pin shaft (5); the half-shaft gear (2) is axially mounted inside the outer shell (1); the half-shaft gear (2) is meshed with the planetary gear (7); a first oil inlet hole (11) is provided at the end of the outer shell (1); a radial oil passage (52) is provided inside the planetary pin shaft (5); an axial oil hole (51) which is connected to the radial oil passage (52) is provided on the side of the planetary pin shaft (5); the radial oil passage (52) is connected to the first oil inlet hole (11) through an elastic pin shaft (4); lubricating oil enters the radial oil passage (52) through the first oil inlet hole (11) and the elastic pin shaft (4), and flows to the matching surface between the planetary pin shaft (5) and the planetary gear (7) through the axial oil hole (51).

2. The differential lubrication structure according to claim 1, characterized in that: The planetary pin shaft (5) is provided with a detachable sealing plug (8) for sealing the end of the axial oil hole (51).

3. The differential lubrication structure according to claim 2, characterized in that: The side of the elastic pin shaft (4) is provided with a radial oil guide hole (41), and the lubricating oil entering the elastic pin shaft (4) through the first oil inlet hole (11) flows into the axial oil hole (51) through the oil guide hole (41).

4. The differential lubrication structure according to claim 3, characterized in that: The outer shell (1) is also provided with a second oil inlet hole (12) at the end thereof; the first oil inlet hole (11) and the second oil inlet hole (12) are symmetrically arranged at the two ends of the outer shell (1); and the oil inlet directions of the first oil inlet hole (11) and the second oil inlet hole (12) are opposite; the first oil inlet hole (11) and the second oil inlet hole (12) are respectively connected to the two ends of the axial oil hole (51) so as to simultaneously introduce lubricating oil into the two ends of the axial oil hole (51).

5. The differential lubrication structure according to claim 4, characterized in that: The axial oil holes (51) on both sides of the radial oil passage (52) are arranged in pairs on the matching surfaces of the planetary pin shaft (5) and the planetary gear (7).

6. The differential lubrication structure according to any one of claims 1 to 5, characterized in that: Axial mounting holes (53) that are in communication with the radial oil passage (52) are symmetrically arranged at both ends of the planetary pin shaft (5), and the axial mounting holes (53) are used to mount the elastic pin shaft (4).

7. The differential lubrication structure according to claim 6, characterized in that: The two ends of the planetary pin shaft (5) are symmetrically provided with radial mounting holes (54), and the radial mounting holes (54) are located inside the axial mounting holes (53) for connecting the planetary gears (7).

8. The differential lubrication structure according to any one of claims 1 to 5, characterized in that: A gasket (6) is provided between the inner wall of the outer shell (1) and the planetary gear (7).

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