Mechanical finger with T-shaped shaft joint structure

Abstract

The utility model discloses a mechanical finger with a T-shaped shaft joint structure, which comprises a T-shaped shaft component, the T-shaped shaft component comprises a joint part and a shaft part, and a metacarpal bone unit and a finger unit are respectively hinged to two ends of the shaft part and the joint part; one end of the first rotary kinematic pair is connected to the finger unit, and the other end is movably connected to the distal end of the metacarpal bone unit; one end of the second rotary kinematic pair is connected to the finger unit, and the other end is movably connected to the near end of the metacarpal bone unit; when the rotating directions of the first rotating motion pair and the second rotating motion pair are opposite, the finger unit performs side-sway motion along the joint part relative to the metacarpal bone unit; and when the rotating directions of the first rotating motion pair and the second rotating motion pair are the same, the finger unit performs bending motion along the shaft part relative to the metacarpal bone unit. A parallel and stable double-supporting frame is formed, the torsion resistance and lateral load resistance of the joint in the side-sway and bending state are enhanced, and high-rigidity and high-precision double-degree-of-freedom movement in a compact space is achieved.

Description

Technical Field

[0001] This utility model relates to the field of robotics, and in particular to a mechanical finger with a T-shaped joint structure. Background Technology

[0002] In fields such as robotics, prosthetic design, and industrial automation, mechanical fingers are key components for grasping, manipulating, and performing fine motor actions, and their performance directly affects the flexibility, adaptability, and practicality of the entire system.

[0003] Traditional mechanical fingers often employ a series joint configuration, with each phalanx typically connected by a single hinge axis. This structure often suffers from insufficient support rigidity and complex motion coupling when subjected to lateral loads or achieving complex motions. In particular, when finger units need to simultaneously achieve bending and lateral swinging movements, simple single-axis hinges are unable to provide stable and reliable dual-degree-of-freedom support in a compact space, easily leading to phalanx wobbling and decreased accuracy. To avoid these problems, some existing technologies have introduced complex independent drive and compensation mechanisms, but this further increases the complexity of the structure and the difficulty of control. Utility Model Content

[0004] The purpose of this invention is to provide a mechanical finger with a T-shaped shaft joint structure. The T-shaped shaft component is introduced as the core connection and load-bearing element. The metacarpal unit and the finger unit are respectively hinged to the two ends of the T-shaped shaft component, forming a parallel and stable double support frame. This enhances the joint's resistance to torsion and lateral load in lateral swing and bending states, and realizes high rigidity and high precision dual-degree-of-freedom motion in a compact space.

[0005] The above-mentioned technical objective of this utility model is achieved through the following technical solution: a mechanical finger with a T-shaped joint structure, comprising:

[0006] Metacarpal units;

[0007] Finger unit;

[0008] The T-shaped shaft component includes a joint portion and a shaft portion, wherein the metacarpal unit and the finger unit are respectively hinged to the two ends of the shaft portion and the joint portion;

[0009] The first rotational kinematic pair has one end connected to the finger unit and the other end movably connected to the distal end of the metacarpal unit;

[0010] The second rotational kinematic pair has one end connected to the finger unit and the other end movably connected to the proximal end of the metacarpal unit;

[0011] When the first and second rotary kinematic pairs rotate in opposite directions, the finger unit performs a lateral swinging motion relative to the metacarpal unit along the joint; when the first and second rotary kinematic pairs rotate in the same direction, the finger unit performs a bending motion relative to the metacarpal unit along the axis.

[0012] By adopting the above technical solution and introducing a T-shaped shaft component as the connecting core, a rigid parallel support frame is constructed between the metacarpal unit and the finger unit. This structure significantly enhances the overall rigidity and resistance to lateral loads of the joint during lateral swing and bending movements, and ensures the smoothness and stability of the compound movement process.

[0013] A further feature of this invention is that the first rotary kinematic pair rotates along a first axis, and the second rotary kinematic pair rotates along a second axis, wherein the first axis and the second axis are parallel to each other.

[0014] By adopting the above technical solution, the two movement modes of lateral swing and bending of the finger unit are separated, allowing them to be controlled independently without interference. Moreover, the load can be effectively transmitted and distributed through the parallel shaft system and T-shaped shaft components, enhancing the rigidity and load-bearing capacity of the joint.

[0015] A further feature of this invention is that a rotating roller is provided on the hinge shaft of the first rotary kinematic pair, the second rotary kinematic pair and the finger unit, and the joint is sleeved on the rotating roller.

[0016] By adopting the above technical solution, a stable force transmission structure with a clear transmission path and balanced torque is formed, while avoiding interference between lateral swaying motion and bending motion, thus ensuring the smoothness and stability of the compound motion process.

[0017] A further feature of this invention is that: both ends and the middle of the rotating roller are formed with spherical connecting portions, the spherical connecting portions at both ends are movably connected to the first rotary kinematic pair and the second rotary kinematic pair respectively, and the spherical connecting portion in the middle is movably connected to the T-shaped shaft component.

[0018] By adopting the above technical solutions, a flexible connection node with low friction and multi-dimensional compliance is provided. It can adapt to the angle deflection and displacement generated during the movement, effectively release internal assembly stress and movement interference, reduce jamming and wear caused by lateral movement, and improve the flexibility, smoothness and reliability of the joint under lateral movement.

[0019] A further feature of this invention is that when the finger unit is in its initial state, the roller and the shaft are parallel to each other.

[0020] By adopting the above technical solution, in addition to ensuring the support effect on the finger unit, the rotation angle of the first and second rotary kinematic pairs is directly converted into the bending or lateral swing angle of the finger unit, realizing the synchronization of input and output angles, and making the lateral swing and bending motion processes smoother and more stable.

[0021] A further feature of this invention is that the rotating roller is provided with a limiting protrusion, and the limiting protrusion and the spherical connecting portions located on both sides of the rotating roller together restrict the axial movement of the finger unit.

[0022] By adopting the above technical solution, axial movement of the finger unit is effectively prevented when it moves or bears load, making the movement of the finger unit more stable.

[0023] A further configuration of this utility model is as follows: the first rotary kinematic pair includes a first motor fixedly installed at the distal end of the metacarpal unit, a first connecting rod drivenly connected to the first motor, and a second connecting rod drivenly connected to the first connecting rod. The second connecting rod is connected to the shaft of the metacarpal unit. The second rotary kinematic pair includes a second motor fixedly installed at the proximal end of the metacarpal unit, a third connecting rod drivenly connected to the second motor, and a fourth connecting rod drivenly connected to the third connecting rod. The fourth connecting rod is connected to the shaft of the metacarpal unit. The first connecting rod and the third connecting rod are parallel to each other, and the second connecting rod and the fourth connecting rod are parallel to each other.

[0024] By adopting the above technical solution and the above symmetrical and parallel double-link layout, the two kinematic pairs driving the lateral swing and bending are highly consistent in mechanical structure, the motion transmission relationship is more regular and symmetrical, effectively reducing the dynamic coupling and spatial interference between the two motions, and also simplifying the manufacturing, assembly and calibration process of the parts.

[0025] A further feature of this invention is that the metacarpal unit includes an inclined segment, the end of which is hinged to the axial portion of the T-shaped shaft member.

[0026] By adopting the above technical solutions, we can better adapt to the spatial layout constraints of the hand or wrist of the robotic arm, leave sufficient internal space for the movement of the T-axis component and finger unit, avoid interference with the metacarpals or other components, and optimize the initial force transmission angle from the metacarpal unit to the T-axis component.

[0027] A further feature of this invention is that the finger unit includes a first joint and a second joint arranged sequentially from distal to proximal relative to the metacarpal unit. A third motor and a fourth motor are respectively installed in the first joint and the second joint. The third motor and the fourth motor are respectively connected to the shafts of the first joint and the second joint to drive the first joint and the second joint to perform bending movements.

[0028] By adopting the above technical solution, two additional active bending degrees of freedom are provided to the finger unit, which enhances the finger's ability to adaptively wrap around complex-shaped objects, its precise pinching ability, and its dexterity in performing fine operations, making the function of a single finger more powerful and comprehensive.

[0029] In summary, this utility model has the following beneficial effects:

[0030] 1. A T-shaped shaft component is adopted, including a joint and a shaft. The metacarpal unit and the finger unit are hinged to the two ends of the shaft and the joint, respectively. One end of the first rotational kinematic pair is connected to the finger unit, and the other end is movably connected to the distal end of the metacarpal unit. One end of the second rotational kinematic pair is connected to the finger unit, and the other end is movably connected to the proximal end of the metacarpal unit. When the rotation directions of the first and second rotational kinematic pairs are opposite, the finger unit performs lateral swinging motion relative to the metacarpal unit along the joint. When the rotation directions of the first and second rotational kinematic pairs are the same, the finger unit performs bending motion relative to the metacarpal unit along the shaft. By introducing the T-shaped shaft component as the connecting core, a rigid parallel support frame is constructed between the metacarpal unit and the finger unit. This structure significantly enhances the overall rigidity and resistance to lateral loads of the joint during lateral swinging and bending motions, and ensures the smoothness and stability of the compound motion process.

[0031] 2. A rotating roller is installed on the hinge shaft of the first and second rotary kinematic pairs and the finger unit. When the finger unit is in the initial state, the rotating roller is parallel to the shaft. In addition to ensuring the support effect on the finger unit, the rotation angle of the first and second rotary kinematic pairs is directly converted into the bending or lateral swing angle of the finger unit, realizing the synchronization of input and output angles, and making the lateral swing and bending motion process smoother and more stable.

[0032] 3. The first rotary kinematic pair includes a first motor fixedly installed at the distal end of the metacarpal unit, a first link driven by the first motor, and a second link driven by the first link. The second link is connected to the shaft of the metacarpal unit. The second rotary kinematic pair includes a second motor fixedly installed at the proximal end of the metacarpal unit, a third link driven by the second motor, and a fourth link driven by the third link. The fourth link is connected to the shaft of the metacarpal unit. The first link and the third link are parallel to each other, and the second link and the fourth link are parallel to each other. Through the symmetrical and parallel double-link layout, the two kinematic pairs driving the lateral swing and bending are highly consistent in mechanical structure, and the motion transmission relationship is more regular and symmetrical. This effectively reduces the dynamic coupling and spatial interference between the two motions and simplifies the manufacturing, assembly and calibration processes of the parts. Attached Figure Description

[0033] Figure 1 This is a three-dimensional representation of the present invention. Figure 1 .

[0034] Figure 2 This is a three-dimensional representation of the present invention. Figure 2 .

[0035] Figure 3 This is a schematic diagram of the back of this utility model.

[0036] Figure 4 This is a utility model Figure 3 Enlarged view of point A in the middle.

[0037] In the diagram: 1. Metacarpal unit; 11. Inclined segment; 2. Finger unit; 21. First joint; 22. Second joint; 23. Third motor; 24. Fourth motor; 3. T-shaped shaft component; 31. Joint portion; 32. Shaft portion; 4. First rotary kinematic pair; 41. First motor; 42. First connecting rod; 43. Second connecting rod; 5. Second rotary kinematic pair; 51. Second motor; 52. Third connecting rod; 53. Fourth connecting rod; 6. Rotating roller; 61. Spherical connector; 62. Limiting protrusion;

[0038] X1, the first axis; X2, the second axis. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings.

[0040] A mechanical finger with a T-shaped joint structure, such as Figure 1-4 As shown, it includes:

[0041] Metacarpal unit 1 constitutes part of the palm;

[0042] Finger unit 2, which constitutes the entire finger;

[0043] The T-shaped shaft component 3 includes a joint portion 31 and a shaft portion 32, which are perpendicular to each other. The metacarpal unit 1 is hinged to both ends of the shaft portion 32, and the finger unit 2 is hinged to both ends of the joint portion 31.

[0044] The first rotational kinematic pair 4 has one end connected to the finger unit 2 and the other end movably connected to the distal end of the metacarpal unit 1, that is, the end away from the finger unit 2.

[0045] The second rotational kinematic pair 5 has one end connected to the finger unit 2 and the other end movably connected to the proximal end of the metacarpal unit 1, that is, the end close to the finger unit 2.

[0046] When the first rotary kinematic pair 4 and the second rotary kinematic pair 5 rotate in opposite directions, the finger unit 2 performs a lateral swinging motion relative to the metacarpal unit 1 along the joint portion 31; when the first rotary kinematic pair 4 and the second rotary kinematic pair 5 rotate in the same direction, the finger unit 2 performs a bending motion relative to the metacarpal unit 1 along the axis portion 32.

[0047] It should be noted that the first rotary kinematic pair 4 and the second rotary kinematic pair 5 operate synchronously. That is, during lateral swinging motion, the first rotary kinematic pair 4 and the second rotary kinematic pair 5 rotate in different directions, while during bending motion, they rotate in the same direction. Since the first rotary kinematic pair 4 and the second rotary kinematic pair 5 are connected to the metacarpal unit 1 at different positions, their lever arms will be different. In order to keep the first rotary kinematic pair 4 and the second rotary kinematic pair 5 moving synchronously, the rotational speed of the second rotary kinematic pair 5 is greater than that of the first rotary kinematic pair 4. When the first rotary kinematic pair 4 and the second rotary kinematic pair 5 are operating, the finger unit 2 forms an indirect and robust connection with the metacarpal unit 1 through the T-shaped shaft member 3, so that the load can be efficiently transmitted between the metacarpal unit 1 and the finger unit 2 through the rigid body of the T-shaped shaft member 3.

[0048] By introducing a T-shaped shaft component 3 as the connecting core, a rigid parallel support frame is constructed between the metacarpal unit 1 and the finger unit 2. This structure significantly enhances the overall rigidity and resistance to lateral loads of the joint during lateral swing and bending movements, and ensures the smoothness and stability of the compound movement process.

[0049] Preferably, the first rotary kinematic pair 4 rotates along the first axis X1, and the second rotary kinematic pair 5 rotates along the second axis X2, with the first axis X1 and the second axis X2 being parallel to each other. Through this structural design, the lateral swing and bending motion modes of the finger unit 2 are separated, allowing for independent control without interference. Furthermore, the load can be effectively transmitted and distributed through the parallel shaft system and the T-shaped shaft component 3, enhancing the rigidity and load-bearing capacity of the joint.

[0050] It should be noted that the lateral swing motion and the bending motion operate independently; that is, the bending motion does not occur during the lateral swing motion, and vice versa.

[0051] Preferably, a rotating roller 6 is provided on the hinge shaft of the first rotary kinematic pair 4, the second rotary kinematic pair 5, and the finger unit 2, and the joint portion 31 is sleeved on the rotating roller 6. Through the above design, a stable force transmission structure with a clear transmission path and balanced torque is formed, while avoiding interference between lateral swaying motion and bending motion, ensuring the smoothness and stability of the compound motion process.

[0052] Preferably, the roller 6 has spherical connecting portions 61 formed at both ends and in the middle. The spherical connecting portions 61 at both ends are movably connected to the first rotary kinematic pair 4 and the second rotary kinematic pair 5, respectively, and the spherical connecting portion 61 in the middle is movably connected to the joint portion 31. By setting the spherical connecting portions 61, a flexible connecting node with low friction and multi-dimensional compliance is provided. It can adapt to the angular deflection and displacement generated during the movement, effectively release internal assembly stress and motion interference, reduce jamming and wear caused by lateral swinging motion, and improve the flexibility, smoothness and reliability of the joint under lateral swinging motion.

[0053] It should be noted that the finger unit 2 performs a lateral swinging motion along the spherical connecting portion 61 in the middle, and the finger unit 2 performs a bending motion along the hinge axis 32 and the metacarpal unit 1.

[0054] Preferably, when the finger unit 2 is in its initial state, the roller 6 and the shaft 32 are parallel to each other. The initial state is when the finger unit 2 has not yet begun lateral or bending movements. Through the above structural design, in addition to ensuring the support effect for the finger unit 2, the rotation angles of the first rotary kinematic pair 4 and the second rotary kinematic pair 5 are directly converted into the bending or lateral angles of the finger unit 2, achieving synchronization of input and output angles, and making the lateral and bending movements smoother and more stable.

[0055] Preferably, the roller 6 is provided with limiting protrusions 62, which, together with the spherical connecting portions 61 located on both sides of the roller 6, restrict the axial movement of the finger unit 2 along the roller 6. This design effectively prevents the finger unit 2 from axially moving or bearing load, making the movement of the finger unit 2 more stable.

[0056] Preferably, the first rotary kinematic pair 4 includes a first motor 41 fixedly mounted on the distal end of the metacarpal unit 1, a first connecting rod 42 driven by the first motor 41, and a second connecting rod 43 driven by the first connecting rod 42. The second connecting rod 43 is axially connected to the metacarpal unit 1. The second rotary kinematic pair 5 includes a second motor 51 fixedly mounted on the proximal end of the metacarpal unit 1, a third connecting rod 52 driven by the second motor 51, and a fourth connecting rod 53 driven by the third connecting rod 52. The fourth connecting rod 53 is axially connected to the metacarpal unit 1. The first connecting rod 42 and the third connecting rod 52 are parallel to each other, and the second connecting rod 43 and the fourth connecting rod 53 are parallel to each other. Through the above symmetrical and parallel double-link layout, the two kinematic pairs driving lateral swing and bending are highly consistent in mechanical structure, the motion transmission relationship is more regular and symmetrical, effectively reducing the dynamic coupling and spatial interference between the two motions, and also simplifying the manufacturing, assembly and calibration processes of the parts.

[0057] It is worth noting that the direction of the first axis X1 is the setting direction of the output shaft of the first motor 41, and the direction of the second axis X2 is the setting direction of the output shaft of the second motor 51.

[0058] As a preferred embodiment, the first motor 41 and the second motor 51 are arranged coaxially, which reduces the space occupied by the arrangement.

[0059] Preferably, the metacarpal unit 1 includes an inclined segment 11, which is inclined toward the axis 32 of the T-shaped axis member 3, and the end of the inclined segment 11 is hinged to the axis 32 of the T-shaped axis member 3. By setting the inclined segment 11, the spatial layout constraints of the hand or wrist of the robotic hand are better accommodated, providing ample internal space for the movement of the T-shaped axis member 3 and the finger unit 2, avoiding interference with the metacarpals or other components, and also optimizing the initial force transmission angle from the metacarpal unit 1 to the T-shaped axis member 3.

[0060] Preferably, the finger unit 2 includes a first joint 21 and a second joint 22 arranged sequentially from distal to proximal to the metacarpal unit 1. A third motor 23 and a fourth motor 24 are respectively installed in the first joint 21 and the second joint 22. The third motor 23 and the fourth motor 24 are respectively connected to the shafts of the first joint 21 and the second joint 22 to drive the first joint 21 and the second joint 22 to perform bending movements. Through the above structural design, the finger unit 2 is provided with two additional active bending degrees of freedom, which enhances the finger's ability to adaptively wrap around complex-shaped objects, its precise pinching ability, and its dexterity in performing fine operations, making the function of a single finger more powerful and comprehensive.

[0061] It is worth noting that the first motor 41, the second motor 51, the third motor 23, and the fourth motor 24 mentioned above are all worm gear reducers, and their transmission method is the meshing transmission of the worm and the worm wheel.

[0062] The above description is only a preferred embodiment of the present utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of the present utility model patent application are included in the scope of the present utility model patent application.

Claims

1. A mechanical finger having a T-shaped axis joint structure, characterized by, The utility model relates to a kind of prosthetic hand, comprising: Metacarpal unit (1); Finger unit (2); T-shaped shaft component (3), comprising joint part (31) and shaft part (32), the metacarpal unit (1) and the finger unit (2) are respectively articulated in the two ends of the shaft part (32), the joint part (31); First rotary pair (4), one end is connected to the finger unit (2), the other end is movably connected to the distal end of the metacarpal unit (1); Second rotary pair (5), one end is connected to the finger unit (2), the other end is movably connected to the proximal end of the metacarpal unit (1); When the rotary direction of the first rotary pair (4) and the second rotary pair (5) is opposite, the finger unit (2) is relative to the metacarpal unit (1) along the joint part (31) and performs side swing motion;When the rotary direction of the first rotary pair (4) and the second rotary pair (5) is same, the finger unit (2) is relative to the metacarpal unit (1) along the shaft part (32) and performs bending motion.

2. The mechanical finger with a T-shaped axis joint structure according to claim 1, characterized in that: The first rotary pair (4) rotates along the first axis, and the second rotary pair (5) rotates along the second axis, and the first axis and the second axis are parallel to each other.

3. The mechanical finger with a T-shaped axis joint structure according to claim 1, characterized in that: The first rotary pair (4), the second rotary pair (5) and the hinge shaft of the finger unit (2) are provided with a rotating roller (6), and the joint part (31) is sleeved on the rotating roller (6).

4. The mechanical finger having a T-shaped axis joint structure according to claim 3, characterized by: Both ends and the middle part of the rotating roller (6) are formed with spherical connecting parts (61), the spherical connecting parts (61) at both ends are movably connected with the first rotary pair (4) and the second rotary pair (5) respectively, and the spherical connecting part (61) in the middle part is movably connected with the joint part (31).

5. The mechanical finger having a T-shaped axis joint structure according to claim 3, characterized by: When the finger unit (2) is in the initial state, the rotating roller (6) is parallel to the shaft part (32).

6. The mechanical finger having a T-shaped axis joint structure according to claim 4, characterized by: The rotating roller (6) is provided with a limiting protrusion (62), and the limiting protrusion (62) and the spherical connecting parts (61) on both sides of the rotating roller (6) jointly limit the axial movement of the finger unit (2).

7. The mechanical finger having a T-shaped axis joint structure according to claim 1, characterized by: The first rotary pair (4) comprises a first motor (41) fixedly installed at the distal end of the metacarpal unit (1), a first connecting rod (42) in transmission connection with the first motor (41), and a second connecting rod (43) in transmission connection with the first connecting rod (42), wherein the second connecting rod (43) is connected with the metacarpal unit (1) in the shaft, the second rotary pair (5) comprises a second motor (51) fixedly installed at the proximal end of the metacarpal unit (1), a third connecting rod (52) in transmission connection with the second motor (51), and a fourth connecting rod (53) in transmission connection with the third connecting rod (52), wherein the fourth connecting rod (53) is connected with the metacarpal unit (1) in the shaft, the first connecting rod (42) and the third connecting rod (52) are parallel to each other, and the second connecting rod (43) and the fourth connecting rod (53) are parallel to each other.

8. The mechanical finger having a T-shaped axis joint structure according to claim 1, characterized by: The metacarpal unit (1) comprises an inclined section (11), the end of which is hinged to the shaft part (32) of the T-shaped shaft member (3).

9. The mechanical finger having a T-shaped axis joint structure according to any one of claims 1 to 8, characterized in that: The finger unit (2) comprises a first joint (21) and a second joint (22) arranged successively from distal to proximal relative to the metacarpal unit (1), the first joint (21) and the second joint (22) are respectively provided with a third motor (23) and a fourth motor (24), the third motor (23) and the fourth motor (24) are respectively connected with the first joint (21) and the second joint (22) shaft, for driving the first joint (21) and the second joint (22) to bend.

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