Scroll type under-actuated mechanical finger

Abstract

The invention provides a reel type under-actuated mechanical finger, aims to solve the problems of heavy structure and low take-up efficiency in the prior art, and realizes compact structure, light weight and efficient take-up. The finger is mainly composed of a miniature reel, a rack, a near knuckle, a middle knuckle, a far knuckle, a motor, a spring and a traction cable. The knuckles are connected through hinges, a pull wire is adopted to penetrate through wire guide holes in the knuckles from the pin positions of the fingertips far away from the knuckles in an equal-diameter winding mode, and finally the pull wire is fixed to small holes of the miniature reels. Miniature limiting devices and pin holes are designed on the surfaces of the knuckles, knuckle bearings are arranged in the knuckles, spring grooves are formed in the knuckles, and tension springs are arranged in the spring grooves. The scroll is designed to comprise an axial through hole and a radial threaded hole. Through unique design and cooperative cooperation of all the components (especially equal-diameter winding, built-in miniature limiting, spring grooves, tension springs, knuckle bearings and reel structures), the take-up device is light and simple successfully in a limited space, the rope storage efficiency and reliability are remarkably improved, and the take-up device is suitable for being popularized and applied. And the defects of a traditional device are effectively overcome, an innovative thought is provided for miniaturization development of the line-driven mechanical arm, and wide application prospects are achieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of robots, and particularly relates to a reel type under-actuated mechanical finger. BACKGROUND

[0002] In the field of robots, with the continuous development of technology, the management of internal lines of robots is becoming increasingly critical. The traditional take-up device exposes many defects when applied to robots: on the one hand, the internal space of the robot is limited, the traditional take-up device has a complex structure and a large volume, and it is difficult to be reasonably laid out in the narrow mechanical structure, which seriously affects the overall compact design of the robot, and may even interfere with the normal operation of other key components. On the other hand, its heavy weight will increase the load of the robot, reduce the energy utilization efficiency, shorten the cruising range, and is not conducive to the flexible movement and long-time operation of the robot. For example, in the joint parts of some small service robots or precision industrial robots, the requirement for wire harness storage is extremely high, and the traditional take-up method cannot effectively meet the space and weight restrictions of these special parts. Moreover, the complex transmission structure is prone to jamming, wear and other problems during frequent robot movements, which reduces the reliability and stability of the take-up, and further affects the overall performance and service life of the robot.

[0003] For example, CN105960311B discloses a wire driving device and a robot, wherein the wire driving device has a pair of wires, a pair of pulleys, a pair of driven gears, a driving gear and a pair of movable gears, one end of the pair of wires is installed on a movable part, and the movable part is driven in opposition; the other end of each wire is fixed on the pair of pulleys and wound around each wire; the pair of driven gears are coaxially fixed on each pulley; the driving gear is connected with a driving source generating power; the pair of movable gears are arranged between the driving gear and each driven gear, can transmit the power of the driving source from the driving gear to the driven gear, and the movable gear is movably arranged to engage with the driving gear and the driven gear when the driving gear rotates in the direction in which the wire is wound on the pulley, and to disengage from the engagement with at least one of the driving gear and the driven gear when the driving gear rotates in the direction in which the wire is unwound from the pulley.

[0004] In order to solve the problem of complex and large space occupied by the take-up device of the wire-driven robot hand, the present application provides a reel type under-actuated mechanical finger. SUMMARY

[0005] The present application aims to provide a device with compact structure, light weight and high efficiency of take-up, to solve the problems in the prior art.

[0006] The reel type under-actuated mechanical finger mainly comprises a support, a proximal phalanx, a middle phalanx, a distal phalanx, a micro reel, a driving motor, a jackscrew, a tension spring, a joint and a traction cable, the support has a wire hole inside, the proximal phalanx has a wire hole inside, the middle phalanx has a wire hole inside, the micro reel is gap-fitted with the motor output shaft and is fastened through the jackscrew, the tension spring is embedded in the back groove of each phalanx, the joint is provided with a joint bearing with a groove, and the traction cable adopts an equal-diameter winding mode, the first end of the traction cable is fixed to one end of the reel close to the driving motor, and the path of the traction cable sequentially passes through the wire hole inside the support, the wire hole of the proximal phalanx, the joint bearing groove at the joint between the proximal phalanx and the middle phalanx, the wire hole of the middle phalanx, the joint bearing groove at the joint between the middle phalanx and the distal phalanx, and the wire hole of the distal phalanx, and the second end of the traction cable is wound and fixed to the pin inside the distal phalanx.

[0007] According to the above technical scheme, the motor is embedded in the rack, the micro reel is gap-fitted with the motor shaft and is fastened through four jackscrews, the driving motor is embedded in the support, one end of the traction cable is fixed to the pin, and the other end of the traction cable passes through the two micro reel holes and is fixed through the extrusion of the two jackscrews; the position of the wire hole of the support is close to the end face of the micro reel, so that when the driving motor shaft rotates axially to wind the traction cable, the traction cable can be effectively contracted in the radial direction of the reel.

[0008] According to the above technical scheme, the surface of the phalanx of the mechanical finger is provided with a micro limiting device, the micro limiting device is provided with a spring groove on the side, the spring groove is provided with a tension spring, the phalanx is provided with a pin hole and a wire hole inside.

[0009] According to the above technical scheme, the micro reel has an axial through hole and a radial threaded hole, the axial through hole is used for assembling the motor shaft, the radial threaded hole is convenient for rotating the jackscrew into the micro reel and the motor shaft, and the radial threaded hole can also fix one end of the traction cable.

[0010] According to the above technical scheme, the surface of the joint bearing is provided with a groove for guiding and limiting the traction cable.

[0011] Compared with the prior art, the reel device of the present application realizes the light and simple wire rope storage function in a limited space, effectively solves the shortcomings of the traditional reel device, improves the efficiency and reliability of wire rope management, provides a new idea for the miniaturization of wire-driven mechanical hands, and has a wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0012] The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of the specification, illustrate embodiments of the application and are used to explain the application, but are not to be considered as limiting the application. In the drawings:

[0013] Figure 1 is a positive isometric view of the reel type underactuated mechanical finger of the present application;

[0014] Figure 2 is an exploded structure view of the reel type underactuated mechanical finger of the present application;

[0015] Figure 3 is an extension view of the reel type underactuated mechanical finger of the present application;

[0016] Figure 4 is an internal wiring view of the reel type underactuated mechanical finger of the present application;

[0017] Figure 5 is an enlarged view of the take-up part of the reel type underactuated mechanical finger of the present application

[0018] Figure 6 is a bending view of the reel type underactuated mechanical finger of the present application.

[0019] In the drawings: 1, frame, 11, micro-limiting stop block at the joint of the proximal phalanx, 12, spring groove, 13, pin hole, 14, wire hole; 2, proximal phalanx, 21, micro-limiting stop block at the joint of the proximal phalanx, 22, spring groove, 23, pin hole, 24, pin hole; 3, middle phalanx, 31, micro-limiting stop block at the joint of the proximal phalanx, 32, spring groove, 33, pin hole, 34, pin hole, 35, wire hole; 4, distal phalanx, 41, micro-limiting stop block at the joint of the proximal phalanx, 42, spring groove, 43, pin hole, 44, wire hole; 5, reel, 51, thread hole near the motor side, 52, thread hole away from the motor side; 6, motor, 61, motor shaft, 62, motor wiring hole; 7, jackscrew; 8, tension spring; 9, joint, 911, proximal phalanx joint bearing, 912, middle phalanx joint bearing, 913, distal phalanx joint bearing, 921, proximal phalanx joint pin, 922, middle phalanx joint pin, 923, distal phalanx joint pin; 10, traction cable. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0021] Please refer to Figures 1-6The application provides a technical scheme: a reel type underdrive mechanical finger, which comprises a support 1, a proximal phalanx 2, a middle phalanx 3, a distal phalanx 4, joints between the proximal phalanx 2, the middle phalanx 3 and the distal phalanx 4 are connected through a pin 921, a pin 922 and a pin 923 to form a hinge connection, so that the three phalanges can rotate relative to each other.

[0022] Please refer to Figure 1 and 3 A micro-limiting structure 21, a micro-limiting structure 31 and a micro-limiting structure 41 are respectively arranged on the edges of a finger phalanx spring groove 22, a spring groove 32 and a spring groove 42, so as to prevent the finger from bending in the opposite direction and turning over when the finger is stressed, and affecting normal gripping of the finger.

[0023] Please refer to Figure 1 and 4 A spring groove 12, a spring groove 22, a spring groove 32 and a spring groove 42 are arranged on the back of the finger phalanx, and a spring 8 is arranged in the spring grooves, so that the spring 8 generates a restoring force when the finger is bent, and the finger can automatically stretch.

[0024] Please refer to Figures 2-4 A micro-reel 51, a micro-reel 52, a micro-reel 53 and a micro-reel 54 are arranged on the micro-reel 5, and when the reel 5 cooperates with a motor shaft 61, the four positions of the micro-reels are fixed by a jack 71, a jack 72, a jack 73 and a jack 74.

[0025] Please refer to Figure 4 and 5 A wire 10 passes through a wire hole 44, is fixed on a pin at a pin hole 43, sequentially passes through a distal phalanx joint bearing 913, a pin 34, a wire hole 35, a pin 33, a middle phalanx joint bearing 912, a pin 24, a wire hole 25, a pin 24, a proximal phalanx joint bearing 911, a wire hole 14, and finally passes through a micro-reel hole 54 and a micro-reel hole 52 of the reel 5, and the traction cable 10 is fixed by the jack 74 and the jack 72, so that when the motor shaft 61 rotates, the wire 10 is wound on the surface of the micro-reel 5, the length of the wire 10 in the phalanx is shortened, the finger is bent, and the bending angle is related to the traction cable: L=L0-r(θ1+θ2+θ3), wherein L0 is an initial wire length, r is the radius of the groove bearing 91, θ1 is a proximal phalanx joint rotation angle, θ2 is a middle phalanx joint rotation angle, and θ3 is a distal phalanx joint rotation angle.

[0026] The application is a reel type under-actuated mechanical finger embodiment: the traction cable 10 is first threaded through the guide hole 44, fixed on the pin in the pin hole 43, and then threaded through the distal joint bearing 913, the pin 34, the guide hole 35, the pin 33, the middle joint bearing 912, the pin 24, the guide hole 25, the pin 24, the proximal joint bearing 911, the guide hole 14, forming an equal diameter winding, and finally threaded through the micro-reel hole 54 and the micro-reel hole 52 of the reel 5, and fixed with the jackscrew 74 and the jackscrew 72, respectively. When the motor shaft 61 rotates, the cable 10 is wound on the surface of the reel 5, so that the total length of the cable 10 in the finger joint is shortened, and the finger is bent. The groove bearing diameter is 9.5m, the micro-reel radius is 4m, the bending angles of the three joints of the finger are 80, 100 and 90 degrees, respectively, and the change amount of the traction cable when the finger reaches the final bending state is about 22.38m, and the micro-reel rotates about 5.6ad, as shown in Figure 6 ; when the motor reverses, the traction cable becomes longer, and the finger gradually returns to the initial state due to the restoring force of the spring, as shown in Figure 3 .

[0027] Finally, it should be pointed out that the above is only the preferred embodiment of the application and is not intended to limit the application. Although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent replacements to some technical features. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A reel-type underactuated mechanical finger, characterized in that, include: The device comprises a support (1), a proximal phalanx (2), a middle phalanx (3), a distal phalanx (4), a miniature spool (5), a drive motor (6), a set screw (7), a tension spring (8), a joint (9), and a traction cable (10). The support (1) has a wire hole (15) inside, the proximal phalanx (2) has a wire hole (25) inside, and the middle phalanx (3) has a wire hole (35) inside. The miniature spool (5) and the output shaft (61) of the motor (6) are fitted with a clearance and secured by the set screw (7). The tension spring (8) is embedded in the groove on the back of each phalanx. The joint (9) is equipped with a grooved joint bearing 1 (911) and a joint bearing 2 (911). 912), joint bearing 3 (913); the traction cable (10) adopts an equal diameter winding method, and its first end is fixed to the end (52) of the reel (5) near the drive motor. Its path passes through the following in sequence: the wire hole (15) inside the bracket (1), the wire hole (25) of the proximal phalanx, the joint shaft groove 1 (911) at the connection between the proximal phalanx (2) and the intermediate phalanx (3), the wire hole (35) of the intermediate phalanx, the joint bearing groove 2 (912) at the connection between the intermediate phalanx (3) and the distal phalanx (4), and the wire hole (45) of the distal phalanx. The second end of the traction cable is wound and fixed to the pin (43) inside the distal phalanx.

2. The underactuated mechanical finger according to claim 1, characterized in that: The micro-coil holes 1 (51), 2 (52), 3 (53), and 4 (54) are respectively fitted with set screws 1 (71), 2 (72), 3 (73), and 4 (74) to fix the micro-coil (5) on the output shaft (61) of the drive motor. The drive motor (6) is embedded in the bracket (1). One end of the traction cable is fixed to the pin (43), and the other end passes through the micro-coil holes 4 (54) and 2 (52) and is pressed and fixed by set screws 2 (72) and 4 (74). The position of the wire hole (15) of the bracket is such that when the drive motor shaft (61) rotates axially to wind the traction cable, the traction cable (10) can effectively contract in the radial direction of the coil (5).

3. The underactuated mechanical finger according to claim 1, characterized in that: The proximal phalanx (2), intermediate phalanx (3) and distal phalanx (4) are provided with micro-limiting structures 1 (21), 2 (31) and 3 (41) on the back of the fingers to increase joint strength and limit excessive bending of the phalanx in the direction of extension.

4. The underactuated mechanical finger according to claim 1, characterized in that: The grooves on the spherical bearings 1 (911), 2 (912), and 3 (913) are used to guide and limit the traction cable (10), while the spherical bearings (9) are rotatable.

5. The underactuated mechanical finger according to claim 1, characterized in that: The tension springs (8) located on the back of each phalanx generate a restoring force that allows the finger body to remain or return to an extended state when the traction cable (10) is released.

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