Self-locking differential

Abstract

A kind of self-locking differential, including left inner disc and right inner disc being arranged in middle shell, control disc being arranged between left inner disc and right inner disc in middle shell, left and right end surfaces of control disc respectively extend to left inner disc and right inner disc peripheral surface and form multiple evenly arranged arc plate structures, and hollow roller placement slot is opened in the middle part of each arc plate structure, and one roller is placed in each roller placement slot, the diameter of roller is greater than the thickness of arc plate structure, and the inner side wall of middle shell is provided with multiple roller limiting grooves corresponding to roller, and the bottom surface of roller limiting groove on both sides of roller is formed wedge surface by gradually shallow from middle to both sides.The axial force is not generated in the process of torque transmission, and the torsion transmission efficiency is high;Automatic locking can be realized, and unilateral wheel edge slip does not occur in driving process or when vehicle starts;In the condition that left and right rotating speeds are inconsistent, differential preferentially drives the wheel edge of slow side.

Description

Technical Field

[0001] This utility model relates to the field of differential technology, specifically a self-locking differential. Background Technology

[0002] Traditional planetary gear differentials (symmetrical bevel planetary gear differentials) are core components of automotive transmission systems. They mainly consist of a differential housing, planetary gears (usually four), half-shaft gears (two), planetary gear shafts, and gaskets. The power transmission path is: main reducer → differential housing → planetary gear shaft → planetary gears → half-shaft gears → half-shaft → wheel. The planetary gears, sun gear (half-shaft gears), and ring gear (differential housing) form a dynamic torque distribution structure. The planetary gears and half-shaft gears are symmetrical in size, ensuring an even distribution of torque between the left and right wheels, regardless of the driving state (straight or turning). The clearance of the planetary gear shaft bore is strictly controlled within 0.1–0.15 mm; the surface roughness of the journal is ≤0.5 µm to ensure lubrication efficiency.

[0003] However, current planetary gear differentials also have drawbacks, such as traction distribution defects and "slippage disadvantage": when one drive wheel loses traction (e.g., getting stuck in mud), the differential will distribute most of the torque to the spinning wheel, causing the vehicle to be unable to get out of trouble. Therefore, a limited-slip differential (LSD) or differential lock needs to be installed to force locking, but this increases cost and complexity. In addition, precision fitting requires high-precision machining, and the repair cost after wear is high. Although the welded structure improves strength, the process is complex, such as high-nickel welding wire to solve the carbon content problem. When the planetary gear system runs at high speed, friction loss increases, and the energy efficiency is lower than at low speed. The compact structure leads to lubrication dead zones, and long-term high load can easily cause gear pitting or journal wear. Utility Model Content

[0004] To address the aforementioned problems, the purpose of this invention is to provide a self-locking differential that, unlike conventional planetary gear structures, does not contain internal gears. Instead, it employs a wedge and roller locking principle to transmit the torque of the passive gear to the half-shaft and wheel edge.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows: a self-locking differential, comprising a left inner plate and a right inner plate disposed within a middle shell, a control plate disposed between the left and right inner plates and located within the middle shell, the left and right inner plates respectively rubbing against the control plate, the left and right end faces of the control plate respectively extending towards the circumference of the left and right inner plates to form multiple evenly arranged arc-shaped plate structures, and each arc-shaped plate structure has a hollowed-out roller placement groove in the middle, each roller placement groove containing a roller, the diameter of the roller being larger than the thickness of the arc-shaped plate structure, the inner sidewall of the middle shell being provided with multiple roller limiting grooves corresponding to the rollers, and the roller limiting grooves gradually becoming shallower from the middle to both sides, so that the bottom surface of the roller limiting grooves on both sides of the rollers forms a wedge surface.

[0006] Furthermore, each roller has a T-shaped push block telescopic cavity on the side wall of the roller placement groove on both sides. Each push block telescopic cavity contains a T-shaped push block. The narrower end of the push block is close to the adjacent roller. The inner end of the push block is elastically supported in the push block telescopic cavity by multiple springs or wave springs.

[0007] Furthermore, annular grooves are provided in the end faces of the left inner plate and the right inner plate, and friction blocks or magnetic blocks that are in close contact with the end face of the control plate are provided in the annular grooves, so that the control plate and the left inner plate and the right inner plate can achieve linkage and speed difference by the resistance of the friction blocks or magnetic blocks.

[0008] Furthermore, the left and right openings of the middle shell are respectively covered by the left and right shells, which have a cylindrical structure in the middle.

[0009] Furthermore, the diameter of the left shell is larger than that of the right shell, and multiple triangular reinforcing ribs are arranged around the cylindrical structure on the outer side of the left shell.

[0010] Furthermore, the annular edge on the left side of the middle shell is in close contact with the left shell, and a ring of evenly arranged mounting holes is provided on the annular edge on the left side of the middle shell, the left shell, and the right shell near the outer edge.

[0011] Furthermore, annular gasket structures are placed between the left inner disc and the left shell, and between the right inner disc and the right shell.

[0012] Furthermore, the inner diameter sidewalls of the left and right inner discs have multiple spline grooves arranged along their axes.

[0013] Furthermore, the length of the roller is greater than the length of the arc-shaped plate structure.

[0014] With the above settings, this utility model does not generate axial force during torque transmission, has low torque loss efficiency, and high torsional transmission efficiency; it can achieve automatic locking, and there will be no slippage on one side of the wheel, whether during driving or when the vehicle starts; in the case of inconsistent left and right speeds, the differential prioritizes driving the wheel with the slower speed, and in the case of excessively low friction on one side of the wheel, the differential prioritizes driving the wheel with higher friction. Attached Figure Description

[0015] The present invention will now be further described with reference to the accompanying drawings.

[0016] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0017] Figure 2 This is a three-dimensional structural diagram of the right side of this utility model;

[0018] Figure 3This is a three-dimensional structural diagram of the left side of this utility model;

[0019] Figure 4 This is a schematic diagram of the main cross-sectional structure of this utility model;

[0020] Figure 5 This is a side view cross-sectional structural diagram of the present invention;

[0021] Figure 6 This is an enlarged cross-sectional structural diagram of the roller part of this utility model;

[0022] Figure 7 This is a three-dimensional structural diagram of the present invention with the right shell removed;

[0023] Figure 8 This is a three-dimensional structural diagram of the present invention without the outer shell.

[0024] Figure 9 This is a three-dimensional structural diagram of the control panel of this utility model. Detailed Implementation

[0025] like Figure 1-9 As shown, a self-locking differential includes a left inner plate 2 and a right inner plate 3 disposed within a middle shell 1. A control plate 4 located within the middle shell 1 is disposed between the left inner plate 2 and the right inner plate 3. The left and right end faces of the control plate 4 extend towards the circumference of the left inner plate 2 and the right inner plate 3, respectively, to form multiple evenly arranged arc-shaped plate structures. Each arc-shaped plate structure has a hollowed-out roller placement groove 5 in the middle part. A roller 6 is placed in each roller placement groove 5. The diameter of the roller 6 is larger than the thickness of the arc-shaped plate structure. The inner sidewall of the middle shell 1 is provided with multiple roller limiting grooves 7 corresponding to the roller 6. The roller limiting grooves 7 gradually become shallower from the middle to both sides, so that the bottom surface of the roller limiting grooves 7 on both sides of the roller 6 forms a wedge surface 8.

[0026] To ensure a more uniform thrust on each roller 6, T-shaped push block telescopic cavities 9 are provided on the side walls of the roller placement grooves 5 on both sides of each roller 6. Each push block telescopic cavity 9 contains a T-shaped push block 10. The narrower end of the middle part of the push block 10 is close to the adjacent roller 6. The inner end of the push block 10 is elastically supported in the push block telescopic cavity 9 by multiple springs or wave springs 11. The aforementioned springs refer to ordinary helical springs. Thus, when there is an error in the placement groove 5 and the control disk 4 cannot directly push each roller 6 at the same time, the push block 10 can push each roller 6 by compressing the springs or wave springs 11 in the push block telescopic cavity 9, so that each roller 6 has thrust and is locked using each roller 6.

[0027] The left inner disk 2 and the right inner disk 3 respectively rub against the control disk 4. In order for the wheel shafts on both sides to rotate synchronously under normal transmission conditions, the end faces of the left inner disk 2 and the right inner disk 3 are respectively provided with annular grooves. Friction blocks or magnetic blocks 12 that are in close contact with the end face of the control disk 4 are provided in the annular grooves. That is, the left inner disk 2 and the right inner disk 3 respectively rub against the control disk 4 through the friction blocks or magnetic blocks 12, so that the control disk 4 and the left inner disk 2 and the right inner disk 3 achieve linkage and speed difference through the resistance of the friction blocks or magnetic blocks 12.

[0028] Specifically: The left and right openings of the middle shell 1 are respectively covered by the left shell 13 and the right shell 14 with a cylindrical structure in the middle. The diameter of the left shell 13 is larger than the diameter of the right shell 14. Multiple triangular reinforcing ribs 15 are arranged around the cylindrical structure on the outer side of the left shell 13. The annular edge on the left side of the middle shell 1 is in close contact with the left shell 13. A ring of evenly arranged mounting holes 16 is provided on the annular edge on the left side of the middle shell 1, the left shell 13 and the right shell 14 near the outer edge. Annular gasket structures are respectively placed between the left inner plate 2 and the left shell 13, and between the right inner plate 3 and the right shell 14. Multiple spline grooves are opened on the inner diameter sidewalls of the left inner plate 2 and the right inner plate 3 along their axis. The length of the roller 6 is greater than the length of the arc-shaped plate structure. The retraction distance of the push block 10 is less than the locking distance of the two wedge surfaces of the roller 6.

[0029] Working principle of this utility model:

[0030] The driving principle is as follows: When the middle shell 1 rotates, the wedge surface 8, the roller 6, and the inner disk (i.e., the left inner disk 2 and the right inner disk 3) are locked together, achieving coordinated rotation. When the outer shell 1 transmits power to the left inner disk 2 and the right inner disk 3, the driving force drives the slower or more stressed side of the left and right inner disks. For example, when the right tire is on ice, the friction between the tire and the ground is much less than that between the left tire and the ground. Since the middle shell 1 is locked with the left roller 6 and the left inner disk 2, the right side rotates at the same speed as the left side, and there will be no idle rotation.

[0031] When moving forward: When the vehicle starts, moves, or accelerates forward, the engine's torque is transmitted to the tires. The driven gear is bolted to the mounting holes 16 of the middle shell 1 and the left shell 13. When the vehicle moves forward, the driven gear drives the middle shell 1 to drive the left shell 13 and the middle shell 1 to rotate. The control disc 4 is resisted by the friction blocks or magnetic force 12 inside the left inner disc 2 and the right inner disc 3, causing the roller 6 to move relative to the middle shell 1. This causes the wedge surface 8 in the groove of the middle shell 1 to lock the left and right rollers 7, so that the middle shell 1 drives the left inner disc 2 and the right inner disc 3, thereby transmitting the torque of the gear to the half shaft, achieving the condition of the vehicle moving forward. When moving backward, the principle is the same as the opposite direction of forward movement.

[0032] When coasting: When the vehicle is going downhill or coasting with the throttle released, the wheels drive the engine to rotate. In this condition, the left inner plate 2 and the right inner plate 3 drive the roller 6 to lock with the middle shell 1, realizing the reverse dragging condition. Specifically: When the two wheels coast, they rotate and are subjected to force, which gives the left inner plate 2 and the right inner plate 3 a forward driving force. The left inner plate 2 and the right inner plate 3 together drive the friction block or magnetic block 12 to rotate the control plate 4. At the same time, the control plate 4 pushes the roller 6 forward and locks with the wedge surface 8 of the middle shell 1, realizing the left and right inner plates dragging the middle shell 1 in the opposite direction, realizing the reverse dragging condition of coasting.

[0033] When turning: When the vehicle turns left, the left tire rotates slower than the right tire. As the vehicle moves forward, the slower-rotating left roller 6, left inner plate 2, and middle shell 1 are locked. Meanwhile, the right inner plate 3 rotates faster than the middle shell 1. The right inner plate 3 and the friction block or magnetic block 12 drive the control plate 4 to rotate forward. At this time, the push block 10 retracts into the push block extension cavity 9, allowing the roller 6 to enter the middle shell gap space 7. The roller 6 is not in the wedge surface 8, and the right inner plate 3 can achieve a rotation speed greater than that of the middle shell 1. When the right inner plate 3 drives the middle shell 1 to rotate, the left roller 6 is locked, preventing the control plate 4 from rotating continuously. The movement distance of the push block 10 is less than the locking distance of the front and rear wedge surfaces 8 of the middle shell 1. Therefore, during continuous left turns, the right roller 6 and the wedge surface 8 of the middle shell 1 can never reach a locked state, thus achieving the working condition of differential turning.

[0034] The above description is merely an illustrative embodiment of this utility model and is not intended to limit the scope of this utility model. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of this utility model should fall within the protection scope of this utility model.

Claims

1. A self-locking differential, comprising a left inner disc (2) and a right inner disc (3) disposed within a middle housing (1), characterized in that: A control disk (4) located inside the middle shell (1) is provided between the left inner disk (2) and the right inner disk (3). The left inner disk (2) and the right inner disk (3) are in frictional contact with the control disk (4). The left and right end faces of the control disk (4) extend to the circumference of the left inner disk (2) and the right inner disk (3) to form multiple evenly arranged arc-shaped plate structures. Each arc-shaped plate structure has a hollowed-out roller placement groove (5) in the middle. Each roller placement groove (5) contains a roller (6). The diameter of the roller (6) is greater than the thickness of the arc-shaped plate structure. The inner side wall of the middle shell (1) is provided with multiple roller limiting grooves (7) corresponding to the roller (6). The roller limiting grooves (7) gradually become shallower from the middle to both sides, so that the bottom surface of the roller limiting grooves (7) on both sides of the roller (6) forms a wedge surface (8).

2. A self-locking differential as described in claim 1, characterized in that: Each roller (6) has a T-shaped push block telescopic cavity (9) on the side wall of the roller placement groove (5) on both sides. Each push block telescopic cavity (9) has a T-shaped push block (10) in its own part. The narrower end of the middle part of the push block (10) is close to the adjacent roller (6). The inner end of the push block (10) is elastically supported in the push block telescopic cavity (9) by multiple springs or wave springs (11).

3. A self-locking differential as described in claim 1, characterized in that: Annular grooves are provided in the end faces of the left inner plate (2) and the right inner plate (3), and friction blocks or magnetic blocks (12) that are in close contact with the end face of the control plate (4) are provided in the annular grooves, so that the control plate (4) and the left inner plate (2) and the right inner plate (3) can achieve linkage and speed difference by the resistance of the friction blocks or magnetic blocks (12).

4. A self-locking differential as described in claim 1, characterized in that: The left and right openings of the middle shell (1) are respectively covered by the left shell (13) and the right shell (14) with a cylindrical structure in the middle.

5. A self-locking differential as described in claim 4, characterized in that: The diameter of the left shell (13) is larger than that of the right shell (14), and multiple triangular reinforcing ribs (15) are provided around the cylindrical structure on the outer side of the left shell (13).

6. A self-locking differential as described in claim 4, characterized in that: The annular edge on the left side of the middle shell (1) is in close contact with the left shell (13). A ring of evenly arranged mounting holes (16) is provided on the annular edge on the left side of the middle shell (1), the left shell (13), and the right shell (14) near the outer edge.

7. A self-locking differential as described in claim 4, characterized in that: There are annular gasket structures between the left inner plate (2) and the left shell (13), and between the right inner plate (3) and the right shell (14).

8. A self-locking differential as described in claim 1, characterized in that: The inner diameter sidewalls of the left inner plate (2) and the right inner plate (3) have multiple spline grooves arranged along their axis.

9. A self-locking differential as described in claim 1, characterized in that: The length of the roller (6) is greater than the length of the arc-shaped plate structure.

10. A self-locking differential as described in claim 1, characterized in that: The distance by which the push block (10) retracts is less than the distance by which the two wedge surfaces (8) of the roller (6) lock.

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