Differential mechanism with compact structure and electronic locking function
By optimizing the assembly position of the locking mechanism and designing the tapered relationship of the locking ring, combined with electromagnetic control, a mechanical self-locking differential with locking function in a compact structure was achieved. This solved the problem of strength and size matching in existing differentials, and improved the vehicle's ability to get out of trouble and its safety performance.
Patent Information
- Application Number
- CN202520871232.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-06
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2035-05-06
AI Technical Summary
Existing differentials with locking functions have a significantly larger outer envelope size than open differentials to meet the same strength requirements, making them difficult to match with the vehicle. Furthermore, they are prone to failure under increasing factors such as motor torque, vehicle weight, and tire size, affecting driving function and safety.
The assembly position and orientation of the locking mechanism inside the differential are optimized to free up arrangement space. The axial taper of the locking ring teeth is designed to be opposite to the axial taper of the ring body dog teeth. A mechanical self-locking design is adopted, and the locking actuator is controlled by an electromagnetic coil to achieve a compact structure for locking function.
While maintaining the same outer envelope size, the mechanical strength and functional safety of the locking mechanism have been improved, achieving mechanical self-locking under high torque and enhancing the vehicle's ability to get out of trouble and its passability.
Smart Images
Figure CN223868484U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of differential technology, and in particular to a compact differential with electronic locking function. Background Technology
[0002] Currently, most cars on the market employ open differentials between the output shaft of the transmission or reduction gearbox and the corresponding half-shaft. This is to eliminate understeer caused by the difference in turning radii between the inner and outer wheels when cornering, and to address issues affecting the lifespan of the steering mechanism and tires. However, when an open differential encounters a situation where the friction coefficients of the wheels differ significantly—for example, if one wheel loses traction or becomes airborne—the structural characteristics of the open differential prevent torque from being transferred to the wheel with traction, making it impossible for the vehicle to escape such a predicament. Locking differentials, on the other hand, can significantly improve a vehicle's ability to escape such situations. However, due to the added locking and actuator mechanisms, locking differentials often require a significantly larger external envelope than conventional open differentials to achieve the same strength requirements, making them difficult to integrate with vehicle systems. On the other hand, many existing differentials with locking functions have significantly reduced strength after locking in order to maintain a similar size to open differentials. This makes them difficult to adapt to the increasing load, impact, and fatigue caused by the increasing motor torque, vehicle weight, and tire size, leading to premature failure and affecting driving function and safety. Utility Model Content
[0003] This application addresses the shortcomings of existing manufacturing technologies by providing a compact differential with electronic locking functionality. It optimizes the assembly position and orientation of the locking mechanism within the differential, thereby freeing up space for the locking mechanism. While maintaining the same external envelope space for the entire product assembly, the optimized dimensions of the internal locking mechanism enhance the overall mechanical strength of the mechanism. Furthermore, it enables mechanical self-locking of the locking mechanism in the locked state, improving functional safety and maneuverability.
[0004] The technical solution adopted in this utility model is as follows:
[0005] A compact differential with electronic locking function includes a differential housing and a differential gear assembly disposed within the differential housing. The differential housing includes a housing and a cover, the housing having an opening on one side, and the cover being connected to the opening-side end face of the housing.
[0006] The differential gear assembly includes a planetary gear shaft with a cross-shaped structure. The planetary gear shaft is perpendicular to the axis of rotation and is located at the center of the differential housing. A planetary gear is rotatably connected to each of the four ends of the planetary gear shaft via bearings. A first half-shaft gear and a second half-shaft gear are respectively provided at the front and rear parts of the planetary gear shaft. Each of the four planetary gears is meshed with the first half-shaft gear and the second half-shaft gear. The first half-shaft gear and the second half-shaft gear can rotate around the axis of rotation.
[0007] The second half-shaft gear has a protruding gear shaft at the center of its end face facing the housing cover. A locking ring is fitted onto the gear shaft of the second half-shaft gear. The outer ring of the locking ring has multiple radially protruding ring teeth. The opening side end face of the housing cover has multiple ring tooth grooves corresponding to the ring teeth, and the multiple ring teeth can be connected to the multiple ring tooth grooves one-to-one. The end face of the second half-shaft gear facing the locking ring has multiple gear dog teeth, and the end face of the locking ring facing the second half-shaft gear has multiple ring body dog teeth. The multiple gear dog teeth and the multiple ring body dog teeth can be axially meshed and connected to transmit torque. A locking actuation component is provided on the side of the housing cover facing away from the housing. The locking actuation component can contact and push the locking ring to press against the second half-shaft gear.
[0008] Furthermore, four radially penetrating shaft holes are provided on the surface of the housing, and the four ends of the planetary gear shaft are respectively connected to the four shaft holes provided on the housing.
[0009] Furthermore, a planetary gear shim is provided between the planetary gear and the housing, and the planetary gear shim is fitted onto the shaft end of the planetary gear shaft. Two first half-shaft gear shims are provided between the first half-shaft gear and the housing. A protruding gear shaft portion is provided at the center position of the end face of the first half-shaft gear facing the housing. The two first half-shaft gear shims are fitted onto the gear shaft portion of the first half-shaft gear. Two second half-shaft gear shims are provided between the second half-shaft gear and the housing cover. The second half-shaft gear shims are fitted onto the gear shaft portion of the second half-shaft gear.
[0010] Furthermore, the four ends of the planetary gear shaft are respectively provided with through-holes, and planetary gear positioning pins are provided in the positioning holes. Multiple housing positioning holes are provided on the open side end face of the housing, and multiple housing positioning holes are provided on the circumferential end face of the housing cover. The front and rear ends of the planetary gear positioning pins extend into the housing positioning holes and the housing positioning holes, respectively.
[0011] Furthermore, the planetary gear shaft includes a transversely arranged long planetary shaft, with a short planetary shaft mounting hole at the upper and lower ends of the middle of the long planetary shaft, and a short planetary shaft connected to each of the two short planetary shaft mounting holes. The long planetary shaft and the two short planetary shafts are connected to form a cross-shaped structure.
[0012] Furthermore, the axial taper of the locking ring teeth is always designed to be opposite to the axial taper of the ring body's dog teeth, and the angle α1 of the axial taper of the ring teeth is always greater than the angle α2 of the axial taper of the ring body's dog teeth.
[0013] Furthermore, the root width of the locking ring's ring teeth and the gear teeth of the second half-shaft gear are smaller than the tip width.
[0014] Furthermore, a return spring is provided between the locking ring and the second half-shaft gear. The return spring is fitted on the gear shaft of the second half-shaft gear, and the return spring biases the locking ring toward the separation position through spring force.
[0015] Furthermore, the locking actuator includes an actuator ring and an electromagnetic coil. An axially protruding inner shaft portion is provided at the center of the side of the cover facing away from the housing. The actuator ring is fitted on the inner shaft portion of the cover. Multiple protruding actuator claws are provided on the side of the actuator ring facing the cover. The actuator claws can pass through the through holes provided on the cover corresponding to the actuator claw positions and contact the locking ring. A coil mounting groove is provided on the end face of the cover facing away from the housing. The electromagnetic coil is connected in the coil mounting groove. The actuator ring is located in the inner ring of the electromagnetic coil.
[0016] Furthermore, a coil retainer is fitted onto the inner shaft of the housing cover. The inner ring of the coil retainer facing the execution ring has a first positioning end face, and the outer ring of the coil retainer facing the execution ring has a second positioning end face. The first positioning end face can axially contact the side of the execution ring, and the second positioning end face can axially contact the side of the electromagnetic coil. An annular groove is provided on the inner shaft of the housing cover, and a retaining spring is fitted into the annular groove. The retaining spring presses against the side of the coil retainer.
[0017] The beneficial effects of this utility model are as follows:
[0018] This invention, while maintaining the overall outer envelope dimension, moves the mating surface of the housing and cover from the conventional flange face to the non-dog-tooth end face of the locking ring. This allows the radial design dimension of the locking ring to be unrestricted by the dimensions of the internal structure of the housing, enabling the placement of locking rings with larger radial dimensions in this mechanism and improving the mechanical strength of the entire differential locking mechanism. Furthermore, the axial taper of the locking ring teeth in this invention is always opposite to the axial taper angle of the dog-tooth teeth, and the axial taper angle α1 of the ring teeth is always greater than the axial taper angle α2 of the dog-tooth teeth. This ensures that after the dog teeth are engaged, the locking mechanism... The axial force generated by the transmitted torque that causes the dog teeth to tend to separate is always less than the axial force generated simultaneously between the locking ring teeth and the ring tooth groove of the housing 1 that causes the dog teeth to tend to engage, thus realizing the mechanical self-locking of the locking mechanism when subjected to large torque. In this utility model, the dog teeth of the locking ring and the gear dog teeth of the second half-shaft gear are designed with a negative angle design where the root width is less than the tip width. This ensures that the axial force generated by the locking ring and the second half-shaft gear containing the dog teeth when transmitting torque through the dog teeth tends to be in the direction of dog tooth engagement. At this time, when the axial taper α1 of the locking ring teeth and the ring tooth groove of the housing is equal to zero, the locking mechanism can still achieve self-locking. Attached Figure Description
[0019] Figure 1 This is an exploded view of the present invention.
[0020] Figure 2 This is a half-sectional view of the present invention.
[0021] Figure 3 This is a structural diagram of the planetary gear shaft of this utility model.
[0022] Figure 4 This is a structural diagram of the second half-shaft gear of this utility model.
[0023] Figure 5 This is a structural diagram of the second half-shaft gear and locking ring of this utility model.
[0024] The components are: 1. Housing; 2. First half-shaft gear washer; 3. First half-shaft gear; 4. Ring gear groove; 5. Planetary gear washer; 6. Long planetary shaft; 7. Planetary gear; 8. Short planetary shaft; 9. Second half-shaft gear; 10. Planetary shaft locating pin; 11. Second half-shaft gear washer; 12. Return spring; 13. Locking ring; 14. Housing cover; 15. Ring gear; 16. Actuating ring; 17. Electromagnetic coil; 18. Coil retainer; 19. Snap ring; 20. Rotation axis; 21. Shaft hole; 22. Gear dog tooth; 23. Ring body dog tooth; 24. Actuating claw; 25. Inner shaft part of housing cover. Detailed Implementation
[0025] The specific embodiments of this utility model are described below with reference to the accompanying drawings.
[0026] like Figure 1 and Figure 2 As shown, a compact differential with electronic locking function includes a differential housing and a differential gear assembly disposed within the differential housing. The differential housing includes a housing 1 and a cover 14. The housing 1 has an opening on one side, through which the differential gear assembly can be easily installed into the housing 1. The cover 14 is disposed on the opening side of the housing 1, and the cover 14 is connected to the opening side end face of the housing 1 by multiple bolts, and the cover 14 can seal and close the opening of the housing 1.
[0027] like Figure 1 As shown, the differential gear assembly includes a planetary gear shaft with a cross-shaped structure. The planetary gear shaft is perpendicular to the rotation axis 20 and is located at the center of the differential housing. A planetary gear 7 is rotatably connected to each of the four ends of the planetary gear shaft via bearings. A first half-shaft gear 3 and a second half-shaft gear 9 are respectively disposed at the front and rear ends of the planetary gear shaft. Each of the four planetary gears 7 meshes with both the first half-shaft gear 3 and the second half-shaft gear 9, allowing the first half-shaft gear 3 and the second half-shaft gear 9 to rotate around the rotation axis 20.
[0028] like Figure 1 and Figure 2 As shown, four radially through shaft holes 21 are provided on the surface of the housing 1. The four shaft ends of the planetary gear shaft are respectively connected to the four shaft holes 21 provided on the housing 1, and the planetary gear shaft is supported by the shaft holes 21 of the housing 1.
[0029] like Figure 1 As shown, a planetary gear washer 5 is provided between the planetary gear 7 and the housing 1, and the planetary gear washer 5 is fitted onto the shaft end of the planetary gear shaft. Two first half-shaft gear washers 2 are provided between the first half-shaft gear 3 and the housing 1. The first half-shaft gear 3 has a protruding gear shaft portion at the center of the end face facing the housing 1, and the two first half-shaft gear washers 2 are fitted onto the gear shaft portion of the first half-shaft gear 3. Two second half-shaft gear washers 11 are provided between the second half-shaft gear 9 and the housing cover 14. The second half-shaft gear 9 has a protruding gear shaft portion at the center of the end face facing the housing cover 14, and the second half-shaft gear washers 11 are fitted onto the gear shaft portion of the second half-shaft gear 9.
[0030] like Figure 1 As shown, the planetary gear shaft has through-holes at each of its four ends, and planetary gear shaft locating pins 10 are installed in these holes. Multiple housing locating holes are evenly distributed along the circumference on the open side of the housing 1. Multiple housing locating holes are also evenly distributed along the circumference on the circumferential end face of the cover 14. The planetary gear shaft locating pins 10 extend into the housing locating holes and the cover locating holes at their front and rear ends, respectively, to achieve the positioning and installation of the planetary gear shaft.
[0031] like Figure 3 As shown, the planetary gear shaft includes a transversely arranged long planetary shaft 6. A short planetary shaft mounting hole is provided at the upper and lower ends of the middle section of the long planetary shaft 6. A short planetary shaft 8 is connected to each of the two short planetary shaft mounting holes. The long planetary shaft 6 and the two short planetary shafts 8 are connected to form a cross-shaped structure. A planetary gear 7 is connected to the left and right ends of the two short planetary shafts 8 and the long planetary shaft 6, respectively.
[0032] like Figure 1 and Figure 4 As shown, a locking ring 13 is fitted onto the gear shaft of the second half-shaft gear 9. Multiple gear teeth 22 are arranged on the end face of the second half-shaft gear 9 facing the locking ring 13, and these teeth are equidistantly distributed along the circumference. Multiple annular teeth 23 are arranged on the end face of the locking ring 13 facing the second half-shaft gear 9, and these teeth are also equidistantly distributed along the circumference. The gear teeth 22 and annular teeth 23 can mesh axially to transmit torque.
[0033] like Figure 1 and Figure 2 As shown, the outer ring of the locking ring 13 is provided with multiple radially protruding ring teeth 15. On the open side end face of the housing 1, multiple ring tooth grooves 4 are provided corresponding to the multiple ring teeth 15. The multiple ring teeth 15 can be matched and connected in the multiple ring tooth grooves 4 one by one, so that the locking ring 13 can move axially and be assembled into the housing cover 14, but the rotational degree of freedom will always be bound.
[0034] like Figure 5 As shown, the axial taper A of the ring tooth 15 of the locking ring 13 is always opposite to the axial taper B of the ring body dog tooth 23, and the angle α1 of the axial taper A of the ring tooth 15 is always greater than the angle α2 of the axial taper B of the ring body dog tooth 23. This ensures that after the dog teeth are engaged, the axial force generated by the locking mechanism through the dog teeth to make the dog teeth tend to separate is always less than the axial force generated at the same time between the ring teeth of the locking ring 13 and the ring tooth groove of the housing 1 to make the dog teeth tend to engage, thus realizing the mechanical self-locking of the locking mechanism when subjected to large torque. Alternatively, the locking ring 13's ring teeth 23 and the second half-shaft gear 9's gear teeth 22 can be designed with a negative angle where the root width is less than the tip width. This ensures that the axial force generated by the locking ring 13 and the second half-shaft gear 9, which contain these teeth, tends to be in the direction of tooth engagement when transmitting torque through the teeth. At this time, when the axial taper α1 of the locking ring 13's ring teeth 15 and the housing 1's ring tooth groove is zero, the locking mechanism can still achieve self-locking.
[0035] like Figure 1 and Figure 2As shown, a return spring 12 is provided between the locking ring 13 and the second half-shaft gear 9. The return spring 12 is fitted on the gear shaft of the second half-shaft gear 9. The return spring 12 biases the locking ring 13 toward the separation position by the spring force.
[0036] like Figure 1 and Figure 2 As shown, a locking actuator is provided on the side of the cover 14 facing away from the housing 1. The locking actuator and the locking ring 13 can contact each other. When the locking function needs to be performed, the locking actuator can push the locking ring 13 to press against the second half-shaft gear 9 to realize the locking function.
[0037] like Figure 1 and Figure 2 As shown, the locking actuator assembly includes an actuator ring 16 and an electromagnetic coil 17. An axially protruding inner shaft portion 25 is provided at the center of the side of the cover 14 facing away from the housing 1, and the actuator ring 16 is fitted onto the inner shaft portion 25. Multiple protruding actuator claws 24 are provided on the side of the actuator ring 16 facing the cover 14. The actuator claws 24 can pass through through holes on the cover 14 corresponding to the positions of the actuator claws 24 and contact the locking ring 13 inside the differential housing, ultimately enabling adjustment and control of the axial position of the locking ring 13.
[0038] like Figure 1 and Figure 2 As shown, a coil mounting groove is provided on the end face of the cover 14 facing away from the housing 1. An electromagnetic coil 17 is connected in the coil mounting groove. The execution ring 16 is located in the inner ring of the electromagnetic coil 17. The electromagnetic coil 17 generates electromagnetic force by being energized, thereby controlling the axial movement of the execution ring 16.
[0039] like Figure 1 and Figure 2 As shown, a coil retainer plate 18 is mounted on the inner shaft portion 25 of the housing cover. The inner ring of the coil retainer plate 18 facing one side of the execution ring 16 has a first positioning end face, and the outer ring of the coil retainer plate 18 facing one side of the execution ring 16 has a second positioning end face. The first positioning end face can axially contact the side of the execution ring 16, and the second positioning end face can axially contact the side of the electromagnetic coil 17. The coil retainer plate 18 simultaneously achieves axial positioning of both the electromagnetic coil 17 and the execution ring 16. An annular groove is provided on the inner shaft portion 25 of the housing cover, and a retaining spring 19 is fitted into the annular groove. The retaining spring 19 presses firmly against the side of the coil retainer plate 18, achieving positioning and installation of the coil retainer plate 18.
[0040] The working principle of this utility model from the unlocked state to the locked state is as follows: When the electromagnetic coil 17 is powered and the minimum current required to achieve the function is maintained, the generated magnetic force is greater than the frictional resistance of the relevant system components and the resistance of the return spring 12 during the full stroke stage. Therefore, the electromagnetic force can push the actuator ring 16 to move towards the gear set. The actuator claw 24 can pass through the through hole on the cover 14 corresponding to the position of the actuator claw 24 and contact the locking ring 13 inside the differential housing. At this time, the ring teeth 23 of the locking ring 13 and the gear teeth 22 of the second half-shaft gear 9 are axially embedded and meshed. Since the ring teeth 15 of the locking ring 13 are always nested in the ring tooth groove 4 of the housing 1, the rotational degree of freedom of the second half-shaft gear 9 will be bound and locked to the housing 1 through the locking ring 13. Due to the structural characteristics of the differential gear set, the other four planetary gears 7 and the first half-shaft gear 3 of the differential mechanism will also have their rotational degrees of freedom locked, thereby causing the entire differential mechanism to lose its differential function and achieve synchronization of the torque output of the left and right wheels of the corresponding vehicle.
[0041] The working principle of this invention from the locked state to the unlocked state is as follows: When the electromagnetic coil 17 is de-energized, the electromagnetic force it generates disappears. The spring force of the return spring 12 overcomes the friction of the related components, thereby pushing the locking ring 13 to disengage from the second half-shaft gear 9. At this time, both the locking ring 13 and the actuator ring 16 return to their initial unlocked position. The maximum compression stroke of the return spring 12 returns to its preload stroke when unlocked. After disengaging from the locking ring 13, the second half-shaft gear 9 regains its rotational freedom, thus restoring the differential function of the entire differential mechanism and unlocking the differential.
[0042] This invention, while maintaining the overall outer envelope size, moves the mating surface of the housing 1 and the cover 14 from the conventional flange surface to the non-dog tooth end face of the locking ring 13. This allows the differential gear assembly inside the differential housing to be assembled from this mating surface side, and then the return spring 12 and the locking ring 13 are assembled last. This assembly sequence allows the radial design dimension of the locking ring 13 to be unrestricted by the dimensions of the internal structure of the housing 1, thereby allowing for the arrangement of a locking ring 13 with a larger radial dimension in this mechanism, improving the mechanical strength of the entire differential locking mechanism. Meanwhile, the axial taper A of the ring teeth 15 of the locking ring 13 is always opposite to the axial taper B of the ring body dog teeth 23, and the angle α1 of the axial taper A of the ring teeth 15 is always greater than the angle α2 of the axial taper B of the ring body dog teeth 23. This ensures that after the dog teeth are engaged, the axial force generated by the locking mechanism through the torque transmitted by the dog teeth that causes the dog teeth to tend to separate is always less than the axial force generated at the same time between the ring teeth of the locking ring 13 and the ring tooth groove of the housing 1 that causes the dog teeth to tend to engage, thereby realizing the mechanical self-locking of the locking mechanism when subjected to large torque. Alternatively, the locking ring 13's ring teeth 23 and the second half-shaft gear 9's gear teeth 22 can be designed with a negative angle where the root width is less than the tip width. This ensures that the axial force generated by the locking ring 13 and the second half-shaft gear 9, which contain these teeth, tends to be in the direction of tooth engagement when transmitting torque through the teeth. At this time, when the axial taper α1 of the locking ring 13's ring teeth 15 and the housing 1's ring tooth groove is zero, the locking mechanism can still achieve self-locking.
[0043] The above description is an explanation of the present utility model and not a limitation thereof. The scope of the present utility model is defined by the claims. Within the protection scope of the present utility model, any form of modification may be made.
Claims
1. A compact differential with electronic locking function, comprising a differential housing and a differential gear assembly disposed within the differential housing, characterized in that: The differential housing includes a housing (1) and a cover (14). The housing (1) has an opening on one side, and the cover (14) is connected to the opening side end face of the housing (1). The differential gear assembly includes a planetary gear shaft with a cross-shaped structure. The planetary gear shaft is perpendicular to the rotation axis (20) and is located at the center of the differential housing. A planetary gear (7) is rotatably connected to each of the four ends of the planetary gear shaft through bearings. A first half-shaft gear (3) and a second half-shaft gear (9) are respectively provided at the front and rear parts of the planetary gear shaft. Each of the four planetary gears (7) is meshed with the first half-shaft gear (3) and the second half-shaft gear (9). The first half-shaft gear (3) and the second half-shaft gear (9) can rotate around the rotation axis (20). The second half-shaft gear (9) has a protruding gear shaft at the center of its end face facing the housing cover (14). A locking ring (13) is fitted onto the gear shaft of the second half-shaft gear (9). The outer ring of the locking ring (13) has multiple radially protruding ring teeth (15). Multiple ring tooth grooves (4) are provided on the open side end face of the housing (1) corresponding to the multiple ring teeth (15). The multiple ring teeth (15) can be connected to the multiple ring tooth grooves (4) one by one. Multiple gear teeth (22) are provided on the end face of the locking ring (13) facing the second half-shaft gear (9), and multiple ring teeth (23) are provided on the end face of the locking ring (13) facing the second half-shaft gear (9). The multiple gear teeth (22) and multiple ring teeth (23) can be axially meshed and connected to transmit torque. The cover (14) is provided with a locking actuator on the side facing away from the housing (1). The locking actuator can contact and push the locking ring (13) to press against the second half-shaft gear (9).
2. A differential with electronic locking function in a compact structure as described in claim 1, characterized in that: The surface of the housing (1) is provided with four radially penetrating shaft holes (21), and the four shaft ends of the planetary gear shaft are respectively connected to the four shaft holes (21) provided on the housing (1).
3. A differential with electronic locking function and a compact structure as described in claim 2, characterized in that: A planetary gear shim (5) is provided between the planetary gear (7) and the housing (1). The planetary gear shim (5) is fitted onto the shaft end of the planetary gear shaft. Two first half-shaft gear shims (2) are provided between the first half-shaft gear (3) and the housing (1). A protruding gear shaft portion is provided at the center position of the end face of the first half-shaft gear (3) facing the housing (1). The two first half-shaft gear shims (2) are fitted onto the gear shaft portion of the first half-shaft gear (3). Two second half-shaft gear shims (11) are provided between the second half-shaft gear (9) and the housing cover (14). The second half-shaft gear shims (11) are fitted onto the gear shaft portion of the second half-shaft gear (9).
4. A differential with electronic locking function in a compact structure as described in claim 3, characterized in that: The four ends of the planetary gear shaft are respectively provided with a through-hole. The planetary gear positioning pin (10) is provided in the positioning hole. Multiple housing positioning holes are provided on the open side end face of the housing (1). Multiple housing positioning holes are provided on the circumferential end face of the cover (14). The front and rear ends of the planetary gear positioning pin (10) extend into the housing positioning hole and the cover positioning hole, respectively.
5. A compact differential with electronic locking function as described in claim 4, characterized in that: The planetary gear shaft includes a transversely arranged long planetary shaft (6), with a short planetary shaft mounting hole at the upper and lower ends of the middle part of the long planetary shaft (6), and a short planetary shaft (8) connected in the upper and lower short planetary shaft mounting holes respectively. The long planetary shaft (6) and the two short planetary shafts (8) are connected to form a cross-shaped structure.
6. A compact differential with electronic locking function as described in claim 5, characterized in that: The axial taper of the ring tooth (15) of the locking ring (13) is always opposite to the axial taper of the ring body dog tooth (23), and the angle α1 of the axial taper of the ring tooth (15) is always greater than the angle α2 of the axial taper of the ring body dog tooth (23).
7. A differential with electronic locking function in a compact structure as described in claim 6, characterized in that: The root width of the locking ring (13) and the gear dog tooth (22) of the second half-shaft gear (9) is smaller than the tooth tip width.
8. A differential with electronic locking function in a compact structure as described in claim 7, characterized in that: A return spring (12) is provided between the locking ring (13) and the second half-shaft gear (9). The return spring (12) is mounted on the gear shaft of the second half-shaft gear (9). The return spring (12) biases the locking ring (13) toward the separation position by spring force.
9. A compact differential with electronic locking function as described in claim 8, characterized in that: The locking actuator includes an actuator ring (16) and an electromagnetic coil (17). The inner shaft portion (25) of the cover (14) is axially protruding at the center position on the side facing away from the housing (1). The actuator ring (16) is fitted on the inner shaft portion (25). The actuator ring (16) has multiple protruding actuator claws (24) on the side facing the cover (14). The actuator claws (24) can pass through the through holes on the cover (14) corresponding to the positions of the actuator claws (24) and contact the locking ring (13). The end face of the cover (14) facing away from the housing (1) is provided with a coil mounting groove. The electromagnetic coil (17) is connected in the coil mounting groove. The actuator ring (16) is located in the inner ring of the electromagnetic coil (17).
10. A compact differential with electronic locking function as described in claim 9, characterized in that: A coil clamping plate (18) is fitted on the inner shaft part (25) of the cover. The inner ring of the coil clamping plate (18) facing the side end face of the execution ring (16) is provided with a first positioning end face, and the outer ring of the coil clamping plate (18) facing the side end face of the execution ring (16) is provided with a second positioning end face. The first positioning end face can axially contact the side of the execution ring (16), and the second positioning end face can axially contact the side of the electromagnetic coil (17). An annular groove is provided on the inner shaft part (25) of the cover, and a retaining spring (19) is installed in the annular groove. The retaining spring (19) presses against the side of the coil clamping plate (18).