Finger device of mechanical arm, mechanical arm and robot

Abstract

The utility model relates to the technical field of robots, and provides a mechanical arm finger device, a mechanical arm and a robot, the mechanical arm finger device comprises a transmission assembly, an anti-backlash elastic part and at least one movable knuckle, one end of the movable knuckle is provided with a rotating joint, an installation space is formed in the rotating joint, and a fixed wall is formed in the installation space; the transmission assembly comprises a driving piece and a driven piece which are in power coupling. The transmission assembly is arranged in the mounting space, and the driven part is connected to the corresponding movable knuckle; one end of the anti-backlash elastic piece is fixed on the fixed wall, and the other end is connected to the driven piece or the movable knuckle. According to the finger device of the mechanical arm, the mechanical arm and the robot, the finger device can flexibly move through dynamic coupling between the driving piece and the driven piece; the anti-backlash elastic part is connected with the fixed wall and the driven part, movement of the driven part in the installation space is limited through the elastic force of the anti-backlash elastic part, and therefore shaking of the movable knuckles in the movement process is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of robots, in particular to a finger device of a mechanical arm, a mechanical arm and a robot. Background Art

[0002] The finger device of the existing robot arm has multiple movable knuckles. At the joint of the end of the knuckle, a joint seat is generally provided, and multiple meshing gears are provided inside the joint seat as a transmission component to drive the knuckle to rotate. However, due to the limitation of the processing technology, there is a gap between the gear and the joint seat, which causes the knuckle to shake during the rotation process. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the related art. To this end, the utility model provides a finger device of a mechanical arm, a mechanical arm and a robot, which can prevent the movable knuckle from shaking during movement.

[0004] The utility model provides a finger device of a mechanical arm, comprising:

[0005] At least one movable finger joint, one end of which is provided with a rotating joint, the interior of the rotating joint forms an installation space, and the interior of the installation space forms a fixed wall;

[0006] A transmission assembly, comprising a driving member and a driven member, wherein the driving member and the driven member are dynamically coupled; the transmission assembly is arranged inside the installation space, and the driven member is connected to the corresponding movable knuckle;

[0007] The backlash-eliminating elastic member has one end fixed to the fixed wall and the other end connected to the follower or the movable knuckle.

[0008] According to the finger device of the mechanical arm of the embodiment of the utility model, a connecting shaft is fixedly provided on the driven member, the connecting shaft is connected to the movable finger joint and one end of the connecting shaft is rotatably connected to the fixed wall;

[0009] The backlash-eliminating elastic member is a torsion spring;

[0010] and / or,

[0011] The backlash-eliminating elastic member is sleeved on the connecting shaft;

[0012] and / or,

[0013] A first connecting protrusion is arranged on the connecting shaft, and the first connecting protrusion is suitable for connecting to the first end of the backlash-eliminating elastic member.

[0014] According to the finger device of the robotic arm of the embodiment of the utility model, two anti-backlash elastic members are provided, and the fixed walls are formed on opposite sides of the installation space, and the fixed walls correspond to the anti-backlash elastic members one by one; one of the anti-backlash elastic members is connected to one end of the connecting shaft, and the other anti-backlash elastic member is connected to the other end of the connecting shaft.

[0015] According to the finger device of the mechanical arm of the embodiment of the utility model, the movable finger joint is provided with a connecting portion, and the connecting portion is fixedly connected to the connecting shaft;

[0016] The connecting portion is provided with a threading hole;

[0017] and / or,

[0018] The connecting portion is provided with a receiving groove, the connecting shaft is passed through the side wall of the receiving groove and the driven member is located in the receiving groove.

[0019] According to the finger device of the robot arm of the embodiment of the utility model, a second connecting protrusion is arranged on the fixed wall, and the second connecting protrusion is suitable for connecting the second end of the backlash-eliminating elastic member.

[0020] According to the finger device of the mechanical arm of the embodiment of the utility model, the rotating joint includes a first seat and a second seat, the first seat is provided with a first groove, and the second seat is provided with a second groove; the first seat and the second seat are connected so that the first groove and the second groove are connected to form the installation space; the fixed wall is the inner wall of the first groove or the second groove;

[0021] and / or,

[0022] The movable knuckle comprises a first shell and a second shell, wherein the first shell and the second shell are connected to form a housing space of a driving part of the movable knuckle;

[0023] and / or,

[0024] The movable knuckle located at the end is a finger; the finger includes a first connection shell and a second connection shell that are connected to each other.

[0025] According to the finger device of the robot arm of the embodiment of the utility model, the rotating joint is provided with a matching protrusion on the side facing the movable finger joint, and the movable finger joint is provided with a matching recess that matches with the matching protrusion.

[0026] According to the finger device of the robot arm of the embodiment of the utility model, one of the active member and the driven member is a worm wheel, and the other is a worm, and the worm wheel and the worm are meshed;

[0027] or,

[0028] One of the driving member and the driven member is a driving gear, and the other is a driven gear, and the driving gear and the driven gear are meshed.

[0029] The utility model also provides a mechanical arm, comprising the finger device of the mechanical arm.

[0030] The utility model also provides a robot, comprising the finger device of the mechanical arm or the mechanical arm.

[0031] The above one or more technical solutions in the embodiments of the utility model have at least one of the following technical effects:

[0032] Through the power coupling between the active part and the driven part, the rotation of the movable finger joint is completed, thereby realizing the precise position control of the finger device, so that the finger device can move more freely and flexibly; the anti-backlash elastic part connects the fixed wall and the driven part, and through the elastic force of the anti-backlash elastic part, the movement of the driven part inside the installation space is limited, thereby avoiding the shaking of the movable finger joint during the movement.

[0033] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 It is a schematic diagram of the three-dimensional structure of the finger device of the mechanical arm provided by the embodiment of the utility model;

[0036] Figure 2 It is an exploded view of the finger device of the mechanical arm provided by the embodiment of the utility model;

[0037] Figure 3 It is a schematic diagram of the internal structure of the finger device of the mechanical arm provided by the embodiment of the utility model;

[0038] Figure 4 It is a schematic diagram of the three-dimensional structure of the second seat of the finger device of the robotic arm provided by an embodiment of the utility model.

[0039] Reference numerals:

[0040] 100, movable knuckle; 110, accommodating space; 120, first shell; 130, second shell; 140, matching recess; 150, connecting part; 151, threading hole; 152, accommodating groove;

[0041] 200, rotating joint; 210, installation space; 211, fixed wall; 212, second connecting protrusion; 213, connecting groove; 220, first seat; 221, first groove; 230, second seat; 231, second groove; 240, matching protrusion; 250, bottom plate; 260, weight reduction groove;

[0042] 300, transmission assembly; 310, driving member; 320, driven member; 321, connecting shaft; 3211, first connecting protrusion; 330, first cone wheel; 340, second cone wheel;

[0043] 400, backlash-eliminating elastic member;

[0044] 500, driving unit;

[0045] 600, finger; 610, first connection shell; 620, second connection shell. DETAILED DESCRIPTION

[0046] The following is a further detailed description of the implementation of the present utility model in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present utility model, but cannot be used to limit the scope of the present utility model.

[0047] In the description of the embodiments of the present utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0048] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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 directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0049] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0050] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model embodiment. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0051] See also Figure 1 and Figure 2 The first embodiment of the utility model provides a finger device of a robotic arm, including a transmission assembly 300, a backlash-eliminating elastic member 400 and at least one movable finger joint 100, one end of which is provided with a rotating joint 200, the interior of the rotating joint 200 forms an installation space 210, and the interior of the installation space 210 forms a fixed wall 211; the transmission assembly 300 includes an active member 310 and a driven member 320, and the active member 310 and the driven member 320 are power-coupled; the transmission assembly 300 is arranged inside the installation space 210, and the driven member 320 is connected to the corresponding movable finger joint 100; one end of the backlash-eliminating elastic member 400 is fixed to the fixed wall 211, and the other end is connected to the driven member 320 or the movable finger joint 100.

[0052] The embodiment of the utility model completes the rotation of the movable knuckle 100 through the power coupling between the active member 310 and the driven member 320, thereby achieving precise position control of the finger device, so that the finger device can move more freely and flexibly; the backlash-eliminating elastic member 400 connects the fixed wall 211 and the driven member 320, and through the elastic deformation of the backlash-eliminating elastic member 400, the movement of the driven member 320 inside the installation space 210 is limited, thereby avoiding the shaking of the movable knuckle 100 during the movement.

[0053] It is understandable that the backlash-eliminating elastic member 400 can be disposed in the installation space 210 to reduce the redundant space in the installation space 210 and reduce the possibility of the follower 320 moving inside the installation space 210. Since the backlash-eliminating elastic member 400 has elastic force, it is disposed between the fixed wall 211 and the follower 320. When the movable knuckle 100 rotates, the backlash-eliminating elastic member 400 fills or adjusts the gap between the follower 320 and the fixed wall 211 by elastic deformation, so that the active member 310 and the follower 320 are closely matched to achieve the effect of backlash elimination.

[0054] See also Figure 1 and Figure 2 In one embodiment, a connecting shaft 321 is fixedly provided on the follower 320, the connecting shaft 321 is connected to the movable knuckle 100, and one end of the connecting shaft 321 is rotatably connected to the fixed wall 211; the follower 320 and the movable knuckle 100 are connected by the connecting shaft 321, thereby driving the movable knuckle 100 to move; at the same time, the connecting shaft 321 can be used as the rotation axis of the follower 320, and the connecting shaft 321 is rotatably connected to the fixed wall 211, and the connecting shaft 321 plays a supporting and fixing effect; in order to ensure the smooth rotation of the follower 320, both ends of the connecting shaft 321 are rotatably connected to the inner wall of the installation space 210; Figure 3 As shown, a connection groove 213 may be provided on the inner wall of the installation space 210 , and a connection shaft 321 may be rotatably provided inside the connection groove 213 to further ensure smooth movement of the driven member 320 .

[0055] It is understandable that the backlash-eliminating elastic member 400 may also be directly connected to the follower 320 to limit the shaking of the follower 320 in the installation space 210 ; of course, the backlash-eliminating elastic member 400 may also be connected to the corresponding movable knuckle 100 .

[0056] In one embodiment, Figure 2 As shown, the backlash-eliminating elastic member 400 can be sleeved on the connecting shaft 321 to facilitate the installation of the backlash-eliminating elastic member 400 .

[0057] In order to prevent the backlash-eliminating elastic member 400 from sliding out of the connecting shaft 321, in one embodiment, Figure 2 and Figure 3 As shown, a first connection protrusion 3211 can be provided on the connection shaft 321, and the first connection protrusion 3211 is suitable for connecting the first end of the backlash-eliminating elastic member 400 to fix the backlash-eliminating elastic member 400. Correspondingly, a second connection protrusion 212 can be provided on the fixing wall 211, and the second connection protrusion 212 is suitable for connecting the second end of the backlash-eliminating elastic member 400. By engaging the second connection protrusion 212 with the backlash-eliminating elastic member 400, the installation of the backlash-eliminating elastic member 400 can be completed.

[0058] Generally, the backlash-eliminating elastic member 400 is a torsion spring; the torsion spring can perform self-compensation according to the movement direction and angle of the follower 320, thereby filling the gap; due to the small size of the torsion spring, it is easy to install and arrange; in addition, the torsion spring has good shock absorption and stability performance, which can alleviate the impact and vibration of the finger device to a certain extent. The torsion spring has a spiral portion and a connecting end connected to both ends of the spiral portion, the spiral portion is sleeved on the connecting shaft 321, and the connecting end has at least one bend to facilitate the engagement of the connecting end with the first connecting protrusion 3211 or the second connecting protrusion 212. Of course, in other embodiments, the backlash-eliminating elastic member 400 can also be a compression spring, etc.

[0059] The embodiments of the present invention are not limited to this.

[0060] In one embodiment, two backlash-eliminating elastic members 400 are provided, and fixed walls 211 are formed on opposite sides of the installation space 210, and the fixed walls 211 correspond to the backlash-eliminating elastic members 400 one by one; one of the backlash-eliminating elastic members 400 is connected to one end of the connecting shaft 321, and the other backlash-eliminating elastic member 400 is connected to the other end of the connecting shaft 321. Through the two backlash-eliminating elastic members 400, the movement of the follower 320 can be restricted by both sides of the follower 320 to achieve a better backlash-eliminating effect; of course, in other embodiments, one, three or four backlash-eliminating elastic members 400 can also be provided, and the embodiment of the utility model is not limited to this.

[0061] See also Figure 3 In one embodiment, the movable knuckle 100 is provided with a connecting portion 150, and the connecting portion 150 is fixedly connected to the connecting shaft 321 to drive the movable knuckle 100 to rotate. The connecting portion 150 can be integrally formed with the connecting shaft 321 for easy processing.

[0062] See also Figure 3 In one embodiment, a receiving groove 152 is provided on the connecting portion 150, the connecting shaft 321 is passed through the side wall of the receiving groove 152, and the driven member 320 is located in the receiving groove 152. The receiving groove 152 serves to receive the driven member 320, provides a good working space for the driven member 320, and prevents the driven member 320 from being damaged by external impact force.

[0063] See also Figure 3 In one embodiment, a threading hole 151 is provided on the connecting portion 150; since the finger device needs to connect each movable knuckle 100 through a cable to transmit current and signals, etc., the threading hole 151 provides a channel for the cable to pass through, thereby preventing the cable from being pulled and broken during the movement of the movable knuckle 100.

[0064] See also Figure 2In one embodiment, the rotating joint 200 includes a first seat 220 and a second seat 230, a first groove 221 is set on the first seat 220, and a second groove 231 is set on the second seat 230; the first seat 220 and the second seat 230 are connected so that the first groove 221 and the second groove 231 are connected to form an installation space 210; the fixed wall 211 is the inner wall of the first groove 221 or the second groove 231.

[0065] It can be understood that there is a larger contact area and tightness between the first seat 220 and the second seat 230, which can provide a more secure and stable connection method. Since the transmission assembly 300 is arranged inside the installation space 210, the cooperation between the active member 310 and the driven member 320 requires higher precision, and the size of the general finger device is relatively small, which creates resistance to the installation of the transmission assembly 300; and the embodiment of the utility model forms an installation space 210 for the transmission assembly 300 by connecting the first groove 221 and the second groove 231, which can be easily disassembled and repaired, and the disassembly and assembly are flexible; the rotation joint 200 may include a base plate 250, and the base plate 250 is integrally formed with the first seat 220 or the second seat 230; during installation, the transmission assembly 300 is installed on the base plate 250, and then the first seat 220 and the second seat 230 are connected to complete the assembly of the rotation joint 200.

[0066] See also Figure 4 In one embodiment, at least one of the first seat 220 and the second seat 230 is provided with a weight-reducing groove 260 to reduce the dead weight, so that the finger device as a whole is lighter.

[0067] In one embodiment, one, two, three or four movable knuckles 100 may be provided. By providing multiple movable knuckles 100 and connecting multiple movable knuckles 100 in pairs, the flexibility and adjustability of the finger body can be improved, and the fine control ability of the finger can be improved to provide more accurate operation. By providing multiple movable knuckles 100, the finger body can wrap the target operation object more tightly to adapt to target operation objects of different shapes, and increase the stability and gripping force of the finger body. The embodiment of the utility model does not specifically limit the number of movable knuckles 100.

[0068] See also Figure 2In one embodiment, in order to realize the control of each movable knuckle 100, the movable knuckle 100 also includes a driving unit 500, and the driving unit 500 is suitable for driving the movable knuckle 100 on the lower side along the power transmission direction to move. Generally, the driving unit 500 is a motor. The movable knuckle 100 may include a first shell 120 and a second shell 130, and the first shell 120 and the second shell 130 are connected to form a accommodating space 110 for the driving unit 500 of the movable knuckle 100; the accommodating space 110 is formed by the connection of the first shell 120 and the second shell 130, and the driving unit 500 can be inspected by opening and closing the first shell 120 and the second shell 130. At the same time, the connection between the first shell 120 and the second shell 130 can improve the rigidity and stability of the movable knuckle 100.

[0069] See also Figure 2 In one embodiment, the movable knuckle 100 at the end is a finger 600; the finger 600 can improve the flexibility and gripping force of the finger device. The finger 600 includes a first connection shell 610 and a second connection shell 620 connected to each other. The connection between the first connection shell 610 and the second connection shell 620 can improve the rigidity and stability of the finger 600.

[0070] See also Figure 2 In one embodiment, the rotating joint 200 is provided with a matching protrusion 240 on the side facing the movable knuckle 100, and the movable knuckle 100 is provided with a matching recess 140 that matches with the matching protrusion 240. Since the movable knuckle 100 rotates with the rotating joint 200 as a fulcrum, the matching recess 140 is provided at one end of the movable knuckle 100, so that the rotation of the movable knuckle 100 is smoother; the shape of the matching protrusion 240 can match the matching recess 140, so that the matching protrusion 240 fits with the matching recess 140, thereby increasing the contact area between the movable knuckle 100 and the rotating joint 200, and making the connection between the movable knuckle 100 and the rotating joint 200 more stable.

[0071] See also Figure 2 In one embodiment, one of the active member 310 and the driven member 320 is a worm wheel, and the other is a worm, and the worm wheel and the worm are meshed.

[0072] It is understandable that the transmission of the worm gear can not only achieve a large reduction ratio, but also has a good self-locking characteristic, that is, when the movable finger joint 100 stops rotating, the inclined surface of the worm wheel and the spiral of the worm gear form a blocking effect, which can effectively prevent reversal or rotation, thereby improving the reliability of the transmission assembly 300. Compared with other transmission methods, the worm gear transmission structure is relatively simple and compact, occupies less space, and can achieve a large reduction ratio in the limited space inside the finger device. In addition, the transmission of the worm gear has a relatively stable operation characteristic, and the noise and vibration are relatively small.

[0073] Of course, in other embodiments, one of the driving member 310 and the driven member 320 may be a driving gear and the other may be a driven gear, and the driving gear and the driven gear may be meshed.

[0074] See also Figure 2 The transmission assembly 300 also includes a first bevel wheel 330 and a second bevel wheel 340, which are meshed with each other. The output shaft of the driving unit 500 is fixedly connected to the first bevel wheel 330; the second bevel wheel 340 is coaxially arranged with the active member 310 and rotates synchronously; when the driving unit 500 is working, the first bevel wheel 330 rotates, and the second bevel wheel 340 rotates accordingly, thereby driving the active member 310 to rotate. The first bevel wheel 330 is rotatably arranged on the bottom plate 250, and the second bevel wheel 340 is rotatably connected to the side wall of the installation space 210. The first bevel wheel 330 and the second bevel wheel 340 have the effect of transmitting force and torque. While realizing the direction conversion, the transmission ratio can be changed to realize the speed change. The second cone wheel 340 is fixedly connected to the active member 310, and a square groove can be set on the end surface of the first cone wheel 330, and a square column corresponding to the direction groove can be set on the end surface of the active member 310, and the square column is embedded in the inside of the square groove to achieve the cooperation between the active member 310 and the first cone wheel 330; of course, in other embodiments, the active member 310 and the first cone wheel 330 can also be matched in other ways, and the embodiments of the utility model are not particularly limited to this.

[0075] The second aspect of the utility model also provides a mechanical arm, including the finger device of the mechanical arm.

[0076] It can be understood that if the finger device of the robotic arm has the beneficial effects of the above-mentioned embodiment, then the robotic arm correspondingly has the beneficial effects of the above-mentioned embodiment. Its specific implementation method can refer to the above-mentioned embodiment, and this application will not elaborate on it.

[0077] The third aspect of the utility model also provides a robot, comprising the finger device of the above-mentioned robotic arm or the above-mentioned robotic arm.

[0078] It can be understood that if the finger device and the robotic arm of the robot have the beneficial effects of the above embodiments, then the robot will correspondingly have the beneficial effects of the above embodiments. The specific implementation methods thereof may refer to the above embodiments, and this application will not elaborate on them.

[0079] Finally, it should be noted that the above implementation modes are only used to illustrate the present invention, rather than to limit the present invention. Although the present invention is described in detail with reference to the embodiments, a person skilled in the art should understand that various combinations, modifications or equivalent replacements of the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and should be included in the scope of the claims of the present invention.

Claims

1. A finger device for a robotic arm, characterized in that: include: At least one movable finger joint, one end of which is provided with a rotating joint, the interior of the rotating joint forms an installation space, and the interior of the installation space forms a fixed wall; A transmission assembly, comprising a driving member and a driven member, wherein the driving member and the driven member are dynamically coupled; the transmission assembly is arranged inside the installation space, and the driven member is connected to the corresponding movable knuckle; The backlash-eliminating elastic member has one end fixed to the fixed wall and the other end connected to the follower or the movable knuckle.

2. The finger device of the robot arm according to claim 1, characterized in that: A connecting shaft is fixedly arranged on the driven member, the connecting shaft is connected to the movable finger joint and one end of the connecting shaft is rotatably connected to the fixed wall; The backlash-eliminating elastic member is a torsion spring; and / or, The backlash-eliminating elastic member is sleeved on the connecting shaft; and / or, A first connecting protrusion is arranged on the connecting shaft, and the first connecting protrusion is suitable for connecting to the first end of the backlash-eliminating elastic member.

3. The finger device of the robot arm according to claim 2, characterized in that: There are two backlash-eliminating elastic members, and the fixed walls are formed on opposite sides of the installation space, and the fixed walls correspond to the backlash-eliminating elastic members one by one; one of the backlash-eliminating elastic members is connected to one end of the connecting shaft, and the other backlash-eliminating elastic member is connected to the other end of the connecting shaft.

4. The finger device of the robot arm according to claim 2, characterized in that: The movable knuckle is provided with a connecting portion, and the connecting portion is fixedly connected to the connecting shaft; The connecting portion is provided with a threading hole; and / or, The connecting portion is provided with a receiving groove, the connecting shaft is passed through the side wall of the receiving groove and the driven member is located in the receiving groove.

5. The finger device of a robot arm according to any one of claims 1 to 4, characterized in that: A second connecting protrusion is arranged on the fixed wall, and the second connecting protrusion is suitable for connecting the second end of the backlash-eliminating elastic member.

6. The finger device of a robot arm according to any one of claims 1 to 4, characterized in that: The rotary joint comprises a first seat and a second seat, the first seat is provided with a first groove, and the second seat is provided with a second groove; the first seat and the second seat are connected so that the first groove and the second groove are connected to form the installation space; the fixed wall is an inner wall of the first groove or the second groove; and / or, The movable knuckle comprises a first shell and a second shell, wherein the first shell and the second shell are connected to form a housing space of a driving part of the movable knuckle; and / or, The movable knuckle located at the end is a finger; the finger includes a first connection shell and a second connection shell that are connected to each other.

7. The finger device of a robot arm according to any one of claims 1 to 4, characterized in that: The rotating joint is provided with a matching protrusion on a side facing the movable knuckle, and the movable knuckle is provided with a matching recess which matches with the matching protrusion.

8. The finger device of a robot arm according to any one of claims 1 to 4, characterized in that: One of the active member and the driven member is a worm wheel, and the other is a worm, and the worm wheel and the worm are meshed; or, One of the driving member and the driven member is a driving gear, and the other is a driven gear, and the driving gear and the driven gear are meshed.

9. A robotic arm, characterized in that: A finger device comprising a robotic arm as claimed in any one of claims 1 to 8.

10. A robot, characterized in that: A finger device comprising the robotic arm according to any one of claims 1 to 8 or the robotic arm according to claim 9.

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