CN212331085U

CN212331085U - Three-degree-of-freedom wrist joint structure for rope-driven mechanical arm

Info

Publication number: CN212331085U
Application number: CN202021258735.1U
Authority: CN
Inventors: 贺磊盈; 吴天次; 陈建国
Original assignee: Zhejiang University of Technology ZJUT
Current assignee: Zhejiang University of Technology ZJUT; Zhejiang Sci Tech University ZSTU; Zhejiang University of Science and Technology ZUST
Priority date: 2020-07-01
Filing date: 2020-07-01
Publication date: 2021-01-12
Anticipated expiration: 2030-07-01

Abstract

The utility model relates to a rope-driven arm field. The technical scheme is as follows: the utility model provides a three degree of freedom wrist joint structures for rope drive arm which characterized in that: the structure comprises three motor wheels arranged on a base, a rotary base rotationally positioned on the base, a plurality of pulleys fixed in the base, a transmission shaft rotationally positioned on the rotary base around a horizontal axis, a first reel fixed on the rotary shaft in a penetrating and sleeving manner, a second reel and a third reel rotatably sleeved on the rotary shaft, a first output wheel and two reels fixedly sleeved on the transmission shaft in a penetrating and sleeving manner, a second output wheel rotatably sleeved on the transmission shaft, a tail end platform connected with a rocker, two wire winding rings rotatably sleeved on a first rotary shaft of the universal joint in a penetrating and sleeving manner, two supporting rods sleeved on a second rotary shaft of the universal joint in a penetrating and sleeving manner, two transmission ropes for driving the rotary base, a plurality of transmission ropes for driving the rocker, and a plurality of other transmission ropes for driving the tail end platform. The invention can improve the operable space of the mechanical arm.

Description

Three-degree-of-freedom wrist joint structure for rope-driven mechanical arm

Technical Field

The utility model relates to a rope-driven arm field, concretely relates to three degree of freedom wrist joint structures that are used for rope to drive arm.

Background

In robotics, rope drives are mainly applied to the transmission of parallel mechanisms and robot paws. The rope drive can realize remote transmission, effectively reduces articulated weight, realizes the lightweight of arm, consequently receives people's attention and attention more and more to the research of rope drive arm technique.

In the robot technology, the joints are indispensable members for connecting the hands, arms, body, legs, and feet of the robot. Most of the joints are moved in a rotational or short-range translational motion. Among the various joints, the wrist joint has the most complicated motion and the most freedom. In the existing rope-driven mechanical arm technology, wrist joints are basically two degrees of freedom, and the operable space is limited; therefore, for those needing continuous operation on a spatial curved surface, such as: for robots used for welding, painting, concrete spraying in tunnel boring, etc., a wrist joint having at least three rotational degrees of freedom is absolutely necessary.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming not enough among the above-mentioned background art, providing a three degree of freedom wrist joint structures that is used for rope to drive arm to promote the operable space of arm.

The utility model adopts the technical proposal that:

the utility model provides a three degree of freedom wrist joint structures for rope drive arm which characterized in that: the structure comprises three motor wheels which are arranged on a base and are driven by the motors one by one respectively, a rotary base which is rotationally positioned on the base through a vertically arranged rotary shaft, a plurality of pulleys which are fixed in the base one by one respectively through a plurality of mounting plates, a transmission shaft which is rotationally positioned on the rotary base around a horizontal axis through a bearing seat, a first reel which is sleeved and fixed on the rotary shaft, a second reel and a third reel which are rotationally sleeved on the rotary shaft, a first output wheel and two reels which are fixedly sleeved on the transmission shaft, a second output wheel which is rotationally sleeved and fixed on the transmission shaft and fixedly connected with a rocker, a tail end platform which is connected with the rocker through a universal joint, two wire winding rings which are rotationally sleeved and fixed on a first rotary shaft of the universal joint, two supporting rods which are sleeved and fixed on a second rotary shaft of the universal joint respectively, and two supporting rods which are wound on the first motor wheel and guided through the pulleys and then matched Two transmission ropes of the rotary base, a plurality of transmission ropes driven by the second motor wheel to drive the rocker, and a plurality of transmission ropes driven by the third motor wheel to drive the rest of the tail end platform.

The two reels are a fourth reel and a fifth reel, respectively.

Two driving ropes of the driving rotary base are a first driving rope and a second driving rope.

The mode of driving the rocker is as follows: the ninth transmission rope and the tenth transmission rope are respectively wound on the second motor wheel and are respectively wound on the third reel after passing through the pulley, and the eleventh transmission rope and the twelfth transmission rope are respectively wound on the third reel and are respectively wound on the second output wheel after passing through the pulley, so that the rocker swings under the driving of the motor wheel driven by the motor.

The manner of driving the end platform is: the third transmission rope and the fourth transmission rope are respectively wound on the third motor wheel, pass through the pulley and then are respectively wound on the second reel, and the fifth transmission rope and the sixth transmission rope are respectively wound on the second reel, pass through the pulley and then are respectively wound on the first output wheel; the seventh transmission rope wound on the fourth reel is wound on the first support rod after bypassing the first winding ring; the eighth transmission rope wound on the fifth reel bypasses the second winding ring and then is wound on the second support rod in a loading manner; thereby realizing the driving of the end platform.

The utility model has the advantages that: on the basis of the original two-degree-of-freedom mechanical arm wrist joint, one more degree of freedom can be added to improve the operable space of the mechanical arm, so that the wrist joint can complete all bending, stretching, expanding and contracting motions and the rotation motion within a certain limit.

Drawings

Fig. 1 is a schematic perspective view of the present invention.

Fig. 2 is a second schematic perspective view (rotated 90 degrees with respect to fig. 1) of the present invention.

Fig. 3 is a schematic top view of fig. 2.

Fig. 4 is one of the schematic perspective structures of the inside of the rotating base (after removing the rotating base).

Fig. 5 is a second schematic perspective view of the interior of the rotating base (with the rotating base removed in fig. 1).

Fig. 6 is a third schematic perspective view of the interior of the rotary base (with the rotary base removed in fig. 1).

Fig. 7 is a schematic diagram of a winding structure of one of the motor wheels and the driving rope at the lower part of the base (the motor is omitted in the figure).

Reference numbers in the figures: the spinning mechanism comprises a spinning shaft 1, a bottom plate 2, a spinning base 3, a first transmission rope 4, a second transmission rope 5, a third transmission rope 6, a fourth transmission rope 7, a mounting plate 8, a fifth transmission rope 9, a sixth transmission rope 10, a seventh transmission rope 11, a first winding ring 12, a first support rod 13, an eighth transmission rope 14, a second winding ring 15, a second support rod 16, a ninth transmission rope 17, a tenth transmission rope 18, an eleventh transmission rope 19, a twelfth transmission rope 20, a rocker 21, a transmission shaft 22, a bearing cover 23, a base 24, an end platform 25, a universal joint 26, a bearing seat 27, a fastening retainer ring 28, a key 29, a bearing 30, a motor wheel 31, a first reel I, a second reel II, a third reel III, a fourth reel IV, a fifth reel V, a first output wheel I and a second output wheel II.

Detailed Description

The invention is further explained by the embodiment in the following with the attached drawings; however, the present invention is not limited to the following examples.

As shown in fig. 4, 5 and 6, the base plate 2 is mounted on the inner ring of the bearing 30, the revolving base 3 is mounted on the outer ring of the bearing 30, the bottom of the revolving base is fixed by the bearing cover 23 and is integrally placed on the base 24, and the bottom of the base 24 is mounted with a motor wheel (as shown in fig. 7; the motor is omitted in the figure) driven by the motor.

As shown in fig. 7, the first driving rope 4 and the second driving rope 5 are wound on the motor wheels in the base 24 in pairs, wherein the first driving rope 4 is wound on the motor wheels in a forward direction, and the second driving rope 5 is wound on the motor wheels in a reverse direction (two driving ropes are actually one of the two driving ropes which are connected end to end in a loop; for convenience of description, the two driving ropes are divided into two driving ropes, and the other two pairs of driving ropes (the second driving rope 6 and the third driving rope 7, the ninth driving rope 17 and the tenth driving rope 18) are wound on the other two motor wheels in the base 24 in the same manner (so the other two motor wheels are omitted in the figure).

As shown in fig. 1, 2 and 3, a through groove is formed on the rotary base 1 to allow a transmission rope to pass through, a bearing seat 27 is installed on the upper portion of the rotary base 3 by a screw, and the transmission shaft 22 is installed between the bearing seats 27; the first output wheel i, the fourth reel IV and the fifth reel V are fixedly arranged on the transmission shaft 22, and the second output wheel ii is fixedly connected with the rocker 21 and is sleeved on the transmission shaft 22 in an empty way; the upper part of the rocker is respectively connected with a first support rod 13 and a second support rod 16 of the tail end platform through a universal joint 26 (a first winding ring 12 and a second winding 15 are sleeved at two ends of a second rotating shaft of the universal joint in a sleeving manner and are respectively fixed with the first support rod and the second support rod; the upper part of the rocker is hinged with the first rotating shaft of the universal joint 26) so as to be further connected with the tail end platform 25; wherein, the seventh driving rope wound on the fourth reel can wind on the first fulcrum bar 13 after winding around the first winding ring 12; similarly, the eighth power cord wound on the fifth reel may be wound around the second branch 16 after being wound around the second winding ring 15.

As shown in fig. 4, 5 and 6, the tip end of the rotating shaft 1 is fixed to the upper part of the rotating base 3 by a key 29 and a fastening ring 11; a first reel (I) (not shown) fixedly mounted on the rotation shaft 2 to rotate in synchronism therewith; the second reel (II) and the third reel (III) are sleeved on the rotating shaft 2 in an empty way and are independent from the rotation of the rotating shaft; the matched pulleys are arranged on the inner wall of the rotary base one by one through a plurality of mounting plates 8 (the bottom of each mounting plate is fixed with the rotary base, and the top of each mounting plate is provided with a rotatable pulley).

As shown in fig. 6 and 7, the first drive rope 4 and the second drive rope 5 led out from the first motor wheel are wound on the first reel I (the winding directions of the two ropes are opposite to each other, and the forward and reverse rotation of the first reel is realized); after the motor is started, the winding wheel on the motor wheel is driven to rotate, the rotating shaft 1 is further driven to rotate, and the rotating base 3 is driven to rotate through the two transmission ropes.

As shown in fig. 4, the ninth driving rope 17 and the tenth driving rope 18 led out from the second motor wheel respectively wind around the pulley mounted on the mounting plate 8 and then are wound on the third reel III (the ninth driving rope 17 is wound counterclockwise, the tenth driving rope 18 is wound clockwise; as mentioned above, the two ropes are actually one end-to-end looped); an eleventh transmission rope 19, which is led out from the third reel III first in the counterclockwise direction, is wound around the second output wheel ii in the counterclockwise direction, first by passing around the pulley fixed to the swing base 3; then, the twelfth driving rope 20 (as mentioned above, the eleventh driving rope 19 and the twelfth driving rope 20 are actually one end-to-end looped) led out clockwise from the third reel III is sequentially wound around the pulley fixed on the revolving base 3 and then wound clockwise on the second output wheel ii; the motor wheel driven by the motor drives the second output wheel to rotate, so that the rocker 21 rotates.

As shown in fig. 5 and 6, the third driving rope 6 and the fourth driving rope 7 respectively pass through the pulleys fixed on the mounting plate 8 and are wound on the second reel II (the winding directions of the two ropes are opposite; as mentioned above, the two ropes are actually also one end to end in a loop); then, a fifth driving rope 9 and a sixth driving rope 10 (the winding directions of the two ropes are opposite; as described above, the two ropes are also one end-to-end looped) are led out from the second reel II, respectively, and are wound around the pulley fixed to the revolving base 1 and then wound around the first output wheel i. The reel is still driven by the motor wheel driven by the motor to drive the first output wheel i to rotate.

As shown in fig. 5 and 6, the seventh power cord 11, which is drawn out counterclockwise from the fourth reel IV, is wound around the first winding ring 12 and then around the first stay 13; an eighth driving rope 14 led out clockwise from the fifth reel V, after bypassing the second winding ring 15, is wound around the second stay 16; after the first output wheel i rotates, the fourth reel and the fifth reel synchronously rotate, so that the first supporting rod 13 and the second supporting rod 16 are driven to rotate, and the tail end platform 25 is caused to swing around a second rotating shaft of the universal joint.

Claims

1. The utility model provides a three degree of freedom wrist joint structures for rope drive arm which characterized in that: the structure comprises three motor wheels (31) which are arranged on a base (24) and are respectively driven by the motors one by one, a rotary base (1) which is rotatably positioned on the base through a vertically arranged rotary shaft (2), a plurality of pulleys which are respectively fixed in the base one by one through a plurality of mounting plates (8), a transmission shaft (22) which is rotatably positioned on the rotary base around a horizontal axis through a bearing seat (27), a first reel (I) which is sleeved and fixed on the rotary shaft, a second reel (II) and a third reel (III) which are rotatably sleeved on the rotary shaft, a first output wheel (I) and two reels which are sleeved and fixed on the transmission shaft, a second output wheel (II) which is rotatably sleeved and fixed on the transmission shaft and fixed with a rocker (21), a tail end platform (25) which is connected with the rocker through a universal joint (26), and two winding rings which are rotatably sleeved and fixed on the first rotary shaft of, The two supporting rods which are sleeved on the second rotating shaft of the universal joint in a penetrating mode and are respectively fixed with the tail end platform, the two transmission ropes which are wound on the first motor wheel and are guided by the pulleys and then are wound and matched with the first winding wheel to drive the rotary base, the plurality of transmission ropes which are driven by the second motor wheel to drive the rocker and the plurality of transmission ropes which are driven by the third motor wheel to drive the tail end platform.

2. The three-degree-of-freedom wrist joint structure for the rope-driven mechanical arm according to claim 1, characterized in that: the two reels are a fourth reel (IV) and a fifth reel (V), respectively.

3. The three-degree-of-freedom wrist joint structure for the rope-driven mechanical arm according to claim 2, characterized in that: two transmission ropes of the driving rotary base are a first transmission rope (4) and a second transmission rope (5).

4. The three-degree-of-freedom wrist joint structure for the rope-driven mechanical arm according to claim 3, wherein: the mode of driving the rocker is as follows: the ninth transmission rope (17) and the tenth transmission rope (18) are respectively wound on the second motor wheel and are respectively wound on the third reel (III) after passing through the pulley, and the eleventh transmission rope (19) and the twelfth transmission rope (20) are respectively wound on the third reel and are respectively wound on the second output wheel (ii) after passing through the pulley, so that the rocker swings under the driving of the motor wheel driven by the motor.

5. The three-degree-of-freedom wrist joint structure for the rope-driven mechanical arm according to claim 4, wherein: the manner of driving the end platform is: a third transmission rope (6) and a fourth transmission rope (7) are respectively wound on the third motor wheel, pass through the pulley and then are respectively wound on a second reel (II), and a fifth transmission rope (9) and a sixth transmission rope (10) are respectively wound on the second reel, pass through the pulley and then are respectively wound on a first output wheel (i); a seventh driving rope (11) wound on a fourth reel (IV) and wound on the first branch rod (13) after bypassing the first winding ring (12); an eighth driving rope (14) wound on the fifth reel (V) and wound on the second strut (16) in a loaded manner after winding around the second winding ring (15); thereby realizing the driving of the end platform.