Differential ball joint

Abstract

The invention belongs to the technical field of robots, and discloses a differential ball joint which comprises a shell, a first input bevel gear, a second input bevel gear, an output bevel gear and a phase adjusting assembly, and the first input bevel gear, the second input bevel gear and the output bevel gear are all rotationally arranged on the shell; the first input bevel gear and the second input bevel gear are both meshed with the output bevel gear, and the axis of the output bevel gear is perpendicular to the axis of the first input bevel gear and the axis of the second input bevel gear. The phase adjusting assembly is used for adjusting phases of the first input bevel gear and the second input bevel gear, so that gear teeth in the first input bevel gear and the second input bevel gear make contact with tooth surfaces of two adjacent gear teeth in the output bevel gear, and therefore transmission gaps between the first input bevel gear and the output bevel gear and between the second input bevel gear and the output bevel gear are eliminated. The transmission stability is improved, and the transmission noise is reduced.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, and in particular to a differential ball joint. Background Art

[0002] The joint mechanism is an important structure of the robot, which is the basis for the robot to achieve various actions. In the related art, the joint mechanism consists of a housing, two input bevel gears and an output bevel gear. The rotation of the output gear and / or the housing is achieved by the same-direction rotation and reverse rotation of the two input bevel gears, thereby achieving the pitch, extension and adduction and other actions of the joint mechanism. However, there will be a transmission gap between the two input bevel gears and the output bevel gear, which will affect the transmission accuracy of the joint mechanism, poor transmission stability, and transmission noise. Summary of the invention

[0003] The object of the present invention is to provide a differential ball joint, which eliminates the transmission clearance between the first input bevel gear, the second input bevel gear and the output bevel gear, improves the transmission stability and reduces the transmission noise.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] Differential ball joint, including:

[0006] case;

[0007] A first input bevel gear and a second input bevel gear are both rotatably disposed on the housing;

[0008] An output bevel gear is rotatably disposed on the housing, the output bevel gear is meshed with the first input bevel gear and the second input bevel gear at the same time, and the axis of the output bevel gear is perpendicular to the axes of the first input bevel gear and the second input bevel gear;

[0009] The phase adjustment component is used to adjust the phases of the first input bevel gear and the second input bevel gear so that the gear teeth of the first input bevel gear and the gear teeth of the second input bevel gear contact the tooth surfaces of two adjacent gear teeth in the output bevel gear.

[0010] Preferably, the phase adjustment assembly includes a first capstan, a second capstan, a third capstan, a first pulling member and a second pulling member, the first capstan is fixedly mounted on the shaft of the first input bevel gear, the second capstan is fixedly mounted on the shaft of the second input bevel gear, the third capstan is fixedly mounted on the shaft of the output bevel gear, the first pulling member is wound around the first capstan and the third capstan, one end of the first pulling member is fixedly connected to the third capstan, and the other end is adjustably connected to the third capstan, the second pulling member is wound around the second capstan and the third capstan, one end of the second pulling member is fixedly connected to the third capstan, and the other end is adjustably connected to the third capstan.

[0011] Preferably, the phase adjustment assembly also includes a first sliding member and / or a second sliding member, the first sliding member and / or the second sliding member are slidably connected to the third capstan, the first sliding member is connected to an adjustable end of the first pulling member, and / or the second sliding member is connected to an adjustable end of the second pulling member.

[0012] Preferably, the phase adjustment assembly also includes a first screw and / or a second screw, the first screw and / or the second screw are arranged on the third capstan, the first sliding member is threadedly connected to the first screw, and / or the second sliding member is threadedly connected to the second screw.

[0013] Preferably, the third winch is provided with a first slide groove and / or a second slide groove, the first sliding member is arranged in the first slide groove, and / or the second sliding member is arranged in the second slide groove.

[0014] Preferably, the first capstan is provided with two first through holes, the third capstan is provided with two third through holes, the portion of the first pulling member wound around the first capstan passes through the two first through holes, and the portion of the first pulling member wound around the third capstan passes through the two third through holes;

[0015] And / or, two second through holes are provided on the second capstan, two fourth through holes are provided on the third capstan, the part of the second pulling member wound around the second capstan passes through the two second through holes, and the part of the second pulling member wound around the third capstan passes through the two fourth through holes.

[0016] Preferably, the fixed end of the first pulling member is limited by one of the third through holes to a side of the third capstan away from the winding portion thereof, and the position-adjustable end of the first pulling member is adjustably connected to a side of the third capstan away from the winding portion thereof;

[0017] And / or, the fixed end of the second pulling member is limited by one of the fourth through holes to the side of the third capstan away from its winding portion, and the position-adjustable end of the second pulling member is adjustably connected to the side of the third capstan away from its winding portion.

[0018] Preferably, the first capstan is provided with a first annular winding groove, the second capstan is provided with a second annular winding groove, the third capstan is provided with third and fourth annular winding grooves, the portion of the first pulling member wound on the first capstan is located in the first winding groove, the portion of the first pulling member wound on the third capstan is located in the third winding groove, the portion of the second pulling member wound on the second capstan is located in the second winding groove, and the portion of the second pulling member wound on the third capstan is located in the fourth winding groove.

[0019] Preferably, an auxiliary support member is further included, which is arranged in the shell and located in a space enclosed by the first input bevel gear, the second input bevel gear and the output bevel gear, the first input bevel gear and the second input bevel gear are both rotatably connected to the auxiliary support member, and a shaft in the output bevel gear located on the inner side of the shell passes through the auxiliary support member.

[0020] Preferably, the shell comprises an upper shell and a lower shell, and the upper shell and the lower shell are detachably connected.

[0021] Beneficial effects of the present invention:

[0022] The present invention provides a differential ball joint, comprising a housing, a first input bevel gear, a second input bevel gear, an output bevel gear and a phase adjustment component, wherein the first input bevel gear, the second input bevel gear and the output bevel gear are all rotatably arranged on the housing, the first input bevel gear and the second input bevel gear are both meshed with the output bevel gear, and the axis of the output bevel gear is perpendicular to the axis of the first input bevel gear and the second input bevel gear; the phase adjustment component is used for adjusting the phase of the first input bevel gear and the second input bevel gear, so that the gear teeth in the first input bevel gear and the second input bevel gear are in contact with the tooth surfaces of two adjacent gear teeth in the output bevel gear, thereby eliminating the transmission clearance between the first input bevel gear and the second input bevel gear and the output bevel gear, improving the transmission stability and reducing the transmission noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of a differential ball joint provided by an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of the structure of the differential ball joint provided by an embodiment of the present invention with the upper shell removed;

[0025] Figure 3 is a schematic structural diagram of a differential ball joint provided by an embodiment of the present invention with the upper shell and auxiliary support member removed;

[0026] Figure 4 is a top view of the differential ball joint provided by an embodiment of the present invention with the housing and the auxiliary support member removed;

[0027] Figure 5 is a bottom view of the differential ball joint provided by an embodiment of the present invention with the housing and the auxiliary support member removed;

[0028] Figure 6 is a schematic structural diagram of a differential ball joint provided by an embodiment of the present invention from a first-view perspective after the housing is removed;

[0029] Figure 7 is a schematic structural diagram of a differential ball joint provided by an embodiment of the present invention with the housing removed from a second viewing angle;

[0030] Figure 8 It is a schematic structural diagram of the differential ball joint provided by an embodiment of the present invention from a third perspective after the housing is removed.

[0031] In the figure:

[0032] 10. Housing; 11. Upper housing; 12. Lower housing; 20. First input bevel gear; 21. First input shaft; 22. First input tooth; 30. Second input bevel gear; 31. Second input shaft; 32. Second input tooth; 40. Output bevel gear; 41. First output shaft; 42. Second output shaft; 43. Output tooth; 51. First capstan; 511. First through hole; 52. Second capstan; 521. Second through hole; 53. Third capstan; 531. Third through hole; 532. Fourth through hole; 533, first slide groove; 534, second slide groove; 54, first pulling member; 541, first fixed end; 542, first position adjustable end; 55, second pulling member; 551, second fixed end; 552, second position adjustable end; 56, first sliding member; 57, second sliding member; 58, first screw rod; 59, second screw rod; 61, first outer support bearing; 62, second outer support bearing; 71, first inner support bearing; 72, second inner support bearing; 73, third inner support bearing; 80, auxiliary support member. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0034] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0037] like Figures 1 to 8 As shown, an embodiment of the present invention provides a differential ball joint, including a housing 10, a first input bevel gear 20, a second input bevel gear 30, an output bevel gear 40 and a phase adjustment component, wherein the first input bevel gear 20, the second input bevel gear 30 and the output bevel gear 40 are all rotatably arranged on the housing 10, the first input bevel gear 20 and the second input bevel gear 30 are both meshed with the output bevel gear 40, and the axis of the output bevel gear 40 is perpendicular to the axis of the first input bevel gear 20 and the second input bevel gear 30; the phase adjustment component is used to adjust the phase of the first input bevel gear 20 and the second input bevel gear 30, so that the gear teeth in the first input bevel gear 20 and the second input bevel gear 30 are in contact with the tooth surfaces of two adjacent gear teeth in the output bevel gear 40, thereby eliminating the transmission clearance between the first input bevel gear 20 and the second input bevel gear 30 and the output bevel gear 40, improving the transmission stability and reducing the transmission noise.

[0038] In this embodiment, refer to Figure 2The first input bevel gear 20 includes a first input shaft 21 and a first input tooth portion 22 disposed at one end of the first input shaft 21. The second input bevel gear 30 includes a second input shaft 31 and a second input tooth portion 32 disposed at one end of the second input shaft 31. The output bevel gear 40 includes a first output shaft 41, a second output shaft 42, and an output tooth portion 43 disposed between the first output shaft 41 and the second output shaft 42. The first input shaft 21 is rotatably connected to the housing 10. The first input shaft 21 is rotatably connected to the housing 10. 10, a first inner support bearing 71 is arranged between the second input shaft body 31 and the housing 10, a second inner support bearing 72 is arranged between the second input shaft body 31 and the housing 10, the first output shaft body 41 and the second output shaft body 42 are both rotatably connected to the housing 10, a third inner support bearing 73 is arranged between the first output shaft body 41 and the housing 10, a fourth inner support bearing is arranged between the second output shaft body 42 and the housing 10, and the first input tooth portion 22 and the second input tooth portion 32 are both meshed with the output tooth portion 43. In this embodiment, the differential ball joint further includes an auxiliary support member 80, which is disposed in the housing 10 and is located in a space enclosed by the first input tooth portion 22, the second input tooth portion 32 and the output tooth portion 43. The first output shaft 41 passes through the auxiliary support member 80. The auxiliary support member 80 is provided with a first support portion on the side facing the first input tooth portion 22, and a second support portion on the side facing the second input tooth portion 32. The first input tooth portion 22 is rotatably sleeved on the first support portion, and the second input tooth portion 32 is rotatably sleeved on the second support portion. By providing the auxiliary support member 80, the first input bevel gear 20, the second input bevel gear 30 and the output bevel gear 40 can be auxiliary supported, so that the operation of the first input bevel gear 20, the second input bevel gear 30 and the output bevel gear 40 is more stable.

[0039] In this embodiment, refer to Figure 2 and Figure 3The phase adjustment component includes a first capstan 51, a second capstan 52, a third capstan 53, a first pulling member 54 and a second pulling member 55. The first capstan 51 is fixedly mounted on the first input shaft 21, the second capstan 52 is fixedly mounted on the second input shaft 31, the third capstan 53 is fixedly mounted on the second output shaft 42, the first pulling member 54 is wound around the first capstan 51 and the third capstan 53, one end of the first pulling member 54 is fixedly connected to the third capstan 53, and the other end is adjustably connected to the third capstan 53, the second pulling member 55 is wound around the second capstan 52 and the third capstan 53, one end of the second pulling member 55 is fixedly connected to the third capstan 53, and the other end is adjustably connected to the third capstan 53. By adjusting the position of one adjustable end of the first pulling member 54, the first pulling member 54 can be pre-tightened. When the first pulling member 54 is pre-tightened, the first input bevel gear 20 will change in phase and move closer to the output bevel gear 40, thereby eliminating the transmission gap between the two. Similarly, by adjusting the position of one adjustable end of the second pulling member 55, the second pulling member 55 can be pre-tightened. When the second pulling member 55 is pre-tightened, the second input bevel gear 30 will change in phase and move closer to the output bevel gear 40, thereby eliminating the transmission gap between the two.

[0040] In this embodiment, see Figure 5-Figure 6 as well as Figure 8 The first capstan 51 is provided with two first through holes 511, and the third capstan 53 is provided with two third through holes 531. The portion of the first pulling member 54 wound around the first capstan 51 passes through the two first through holes 511, and the portion of the first pulling member 54 wound around the third capstan 53 passes through two of the third through holes 531. The two ends of the first pulling member 54 are respectively a first fixed end 541 and a first position-adjustable end 542. When the first pulling member 54 is wound around the first capstan 51 and the third capstan 53, firstly, the first position-adjustable end 542 of the first pulling member 54 passes through a third through hole 531 on the third capstan 53 from the side of the third capstan 53 away from the winding portion to the winding portion side of the third capstan 53, and then the first pulling member 54 is wound around the first capstan 51 for at least one turn, and when wound around the first capstan 51, the first pulling member 54 sequentially passes through the two first through holes 511 on the first capstan 51, so that the first pulling member 54 The part is located on the side of the first capstan 51 away from the winding part to prevent the first pulling member 54 from detaching from the first capstan 51, and then the first pulling member 54 is wound around the third capstan 53 for at least one circle, and finally the first position adjustable end 542 of the first pulling member 54 passes through another third through hole 531 on the third capstan 53 from the winding part side of the third capstan 53 to the side away from the winding part. After the first pulling member 54 is wound, its first fixed end 541 is limited to the side of the third capstan 53 away from the winding part, and its first position adjustable end 542 is adjustably connected to the side of the third capstan 53 away from the winding part.

[0041] Similarly, see Figure 3-Figure 4 as well as Figure 7-Figure 8 The second capstan 52 is provided with two second through holes 521, and the third capstan 53 is provided with two fourth through holes 532. The portion of the second pulling member 55 wound around the second capstan 52 passes through the two second through holes 521, and the portion of the second pulling member 55 wound around the third capstan 53 passes through the two fourth through holes 532. The two ends of the second pulling member 55 are respectively a second fixed end 551 and a second position-adjustable end 552. When the second pulling member 55 is wound around the second capstan 52 and the third capstan 53, first, the second position-adjustable end 552 of the second pulling member 55 passes through a fourth through hole 532 on the third capstan 53 from the side of the third capstan 53 away from the winding portion to the winding portion side of the third capstan 53. Then, the second pulling member 55 is wound around the second capstan 52 for at least one turn. When the second pulling member 55 is wound around the second capstan 52, the second pulling member 55 passes through the two second through holes 521 on the second capstan 52 in sequence, so that the second pulling member 55 The part is located on the side of the second capstan 52 away from the winding part to prevent the second pulling member 55 from detaching from the second capstan 52, and then the second pulling member 55 is wound around the third capstan 53 for at least one circle, and finally the second position adjustable end 552 of the second pulling member 55 passes through another fourth through hole 532 on the third capstan 53 from the winding part side of the third capstan 53 to the side away from the winding part. After the winding of the second pulling member 55 is completed, its second fixed end 551 is limited to the side of the third capstan 53 away from the winding part, and its second position adjustable end 552 is adjustably connected to the side of the third capstan 53 away from the winding part.

[0042] In this embodiment, the first capstan 51 is provided with an annular first winding groove, the second capstan 52 is provided with an annular second winding groove, the third capstan 53 is provided with an annular third winding groove and a fourth winding groove, the portion of the first pulling member 54 wound on the first capstan 51 is located in the first winding groove, the portion of the first pulling member 54 wound on the third capstan 53 is located in the third winding groove, the portion of the second pulling member 55 wound on the second capstan 52 is located in the second winding groove, and the portion of the second pulling member 55 wound on the third capstan 53 is located in the fourth winding groove. Through the above arrangement, the stability of the winding of the first pulling member 54 and the second pulling member 55 is further increased.

[0043] Optionally, the first pulling member 54 and the second pulling member 55 may be ropes or chains.

[0044] In this embodiment, see Figure 8The phase adjustment assembly further includes a first sliding member 56 and / or a second sliding member 57, wherein the first sliding member 56 and / or the second sliding member 57 are slidably connected to the third capstan 53, and the first sliding member 56 is connected to the first position-adjustable end 542 of the first pulling member 54, and / or the second sliding member 57 is connected to the second position-adjustable end 552 of the second pulling member 55. By sliding the first sliding member 56, the first position-adjustable end 542 of the first pulling member 54 can be adjusted in position to adjust the preload force of the first pulling member 54; by sliding the second sliding member 57, the second position-adjustable end 552 of the second pulling member 55 can be adjusted in position to adjust the preload force of the second pulling member 55. In other embodiments, the first position-adjustable end of the first pulling member 54 can also be wound on a reeling device, and the position of the first position-adjustable end is adjusted by reeling the reeling device, and the same is true for the second pulling member 55.

[0045] In this embodiment, continue to refer to Figure 8 The phase adjustment assembly further includes a first screw rod 58 and / or a second screw rod 59, which are arranged on the third capstan 53, and a first sliding member 56 is threadedly connected to the first screw rod 58, and / or a second sliding member 57 is threadedly connected to the second screw rod 59. By screwing the first sliding member 56, the first sliding member 56 can be moved along the axis direction of the first screw rod 58, thereby adjusting the position of the first position adjustable end 542 of the first pulling member 54; by screwing the second sliding member 57, the second sliding member 57 can be moved along the axis direction of the second screw rod 59, thereby adjusting the position of the second position adjustable end 552 of the second pulling member 55, and the adjustment method is simple and convenient. In other embodiments, a slide rail can be arranged on the third capstan 53 to slide with the slide member.

[0046] In this embodiment, continue to refer to Figure 8 The third capstan 53 is provided with a first slide groove 533 and / or a second slide groove 534, the first sliding member 56 is provided in the first slide groove 533, and / or the second sliding member 57 is provided in the second slide groove 534. By providing the first slide groove 533 and the second slide groove 534, the movement of the first sliding member 56 and the second sliding member 57 can be limited.

[0047] In this embodiment, see Figure 1 The housing 10 includes an upper shell 11 and a lower shell 12, and the upper shell 11 and the lower shell 12 are detachably connected to facilitate assembly of the overall structure.

[0048] In this embodiment, continue to refer to Figure 1 The housing 10 is supported for rotation by the first outer support bearing 61 and the second outer support bearing 62 .

[0049] The working principle of the differential ball joint provided in this embodiment is as follows: when the first input bevel gear 20 and the second input bevel gear 30 rotate in the same direction and at the same speed, the output bevel gear 40 does not rotate, and the housing 10 rotates under the support of the first outer support bearing 61 and the second outer support bearing 62; when the first input bevel gear 20 and the second input bevel gear 30 rotate in the same direction but at different speeds, the output bevel gear 40 rotates, and the housing 10 also rotates; when the first input bevel gear 20 and the second input bevel gear 30 rotate in opposite directions and at the same speed, the output bevel gear 40 rotates, and the housing 10 does not rotate; when the first input bevel gear 20 and the second input bevel gear 30 rotate in opposite directions but at different speeds, the output bevel gear 40 rotates, and the housing 10 also rotates.

[0050] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A differential ball joint, characterized in that: include: Housing (10); A first input bevel gear (20) and a second input bevel gear (30) are both rotatably disposed on the housing (10); an output bevel gear (40) rotatably disposed on the housing (10), the output bevel gear (40) being meshed with the first input bevel gear (20) and the second input bevel gear (30) at the same time, and the axis of the output bevel gear (40) is perpendicular to the axes of the first input bevel gear (20) and the second input bevel gear (30); A phase adjustment component is used to adjust the phases of the first input bevel gear (20) and the second input bevel gear (30) so that the gear teeth of the first input bevel gear (20) and the gear teeth of the second input bevel gear (30) are in contact with the tooth surfaces of two adjacent gear teeth in the output bevel gear (40).

2. The differential ball joint according to claim 1, characterized in that: The phase adjustment assembly comprises a first capstan (51), a second capstan (52), a third capstan (53), a first pulling member (54) and a second pulling member (55), wherein the first capstan (51) is fixedly sleeved on the shaft of the first input bevel gear (20), the second capstan (52) is fixedly sleeved on the shaft of the second input bevel gear (30), the third capstan (53) is fixedly sleeved on the shaft of the output bevel gear (40), and the first pulling member (54) is fixedly sleeved on the shaft of the output bevel gear (40). The first pulling member (54) is wound around the first capstan (51) and the third capstan (53), one end of the first pulling member (54) is fixedly connected to the third capstan (53), and the other end is adjustably connected to the third capstan (53); the second pulling member (55) is wound around the second capstan (52) and the third capstan (53), one end of the second pulling member (55) is fixedly connected to the third capstan (53), and the other end is adjustably connected to the third capstan (53).

3. The differential ball joint according to claim 2, characterized in that: The phase adjustment assembly further comprises a first sliding member (56) and / or a second sliding member (57), wherein the first sliding member (56) and / or the second sliding member (57) are slidably connected to the third capstan (53), the first sliding member (56) is connected to an end of the first pulling member (54) whose position is adjustable, and / or the second sliding member (57) is connected to an end of the second pulling member (55) whose position is adjustable.

4. The differential ball joint according to claim 3, characterized in that: The phase adjustment assembly also includes a first screw rod (58) and / or a second screw rod (59), wherein the first screw rod (58) and / or the second screw rod (59) are arranged on the third capstan (53), the first sliding member (56) is threadedly connected to the first screw rod (58), and / or the second sliding member (57) is threadedly connected to the second screw rod (59).

5. The differential ball joint according to claim 3, characterized in that: The third capstan (53) is provided with a first slide groove (533) and / or a second slide groove (534), the first sliding member (56) is provided in the first slide groove (533), and / or the second sliding member (57) is provided in the second slide groove (534).

6. The differential ball joint according to claim 2, characterized in that: The first capstan (51) is provided with two first through holes (511), the third capstan (53) is provided with two third through holes (531), the portion of the first pulling member (54) wound around the first capstan (51) passes through the two first through holes (511), and the portion of the first pulling member (54) wound around the third capstan (53) passes through the two third through holes (531); And / or, the second capstan (52) is provided with two second through holes (521), the third capstan (53) is provided with two fourth through holes (532), the portion of the second pulling member (55) wound around the second capstan (52) passes through the two second through holes (521), and the portion of the second pulling member (55) wound around the third capstan (53) passes through the two fourth through holes (532).

7. The differential ball joint according to claim 6, characterized in that: The fixed end of the first pulling member (54) is limited by one of the third through holes (531) to be located at a side of the third capstan (53) away from the winding portion thereof, and the position-adjustable end of the first pulling member (54) is adjustably connected to a side of the third capstan (53) away from the winding portion thereof; And / or, the fixed end of the second pulling member (55) is limited by one of the fourth through holes (532) to a side of the third capstan (53) away from its winding portion, and the position-adjustable end of the second pulling member (55) is adjustably connected to a side of the third capstan (53) away from its winding portion.

8. The differential ball joint according to claim 2, characterized in that: The first capstan (51) is provided with a first annular winding groove, the second capstan (52) is provided with a second annular winding groove, the third capstan (53) is provided with a third annular winding groove and a fourth winding groove, the portion of the first pulling member (54) wound on the first capstan (51) is located in the first winding groove, the portion of the first pulling member (54) wound on the third capstan (53) is located in the third winding groove, the portion of the second pulling member (55) wound on the second capstan (52) is located in the second winding groove, and the portion of the second pulling member (55) wound on the third capstan (53) is located in the fourth winding groove.

9. The differential ball joint according to any one of claims 1 to 8, characterized in that: The invention also includes an auxiliary support member (80), wherein the auxiliary support member (80) is arranged in the housing (10) and is located in a space enclosed by the first input bevel gear (20), the second input bevel gear (30) and the output bevel gear (40); the first input bevel gear (20) and the second input bevel gear (30) are both rotatably connected to the auxiliary support member (80); and a shaft in the output bevel gear (40) located on the inner side of the housing (10) passes through the auxiliary support member (80).

10. The differential ball joint according to any one of claims 1 to 8, characterized in that: The housing (10) comprises an upper shell (11) and a lower shell (12), and the upper shell (11) and the lower shell (12) are detachably connected.

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