WO2017208656A1 - Manipulator - Google Patents

Abstract

One embodiment of a manipulator according to the present invention is characterized by comprising: a first transfer member that links a first rotation member and a third rotation member and transfers a rotation of the first rotation member to the third rotation member via tensile force; and a second transfer member that links a second rotation member and the third rotation member and transfers a rotation of the second rotation member to the third rotation member via tensile force, wherein when a rotational torque in one direction around a first rotational center axis is applied to the first rotation member, the first transfer member transfers, to the third rotation member, a rotational torque in one direction around a second rotational center axis, and when a rotational torque in the one direction around the first rotational center axis is applied to the second rotation member, the second transfer member transfers, to the third rotation member, a rotational torque in the other direction around the second rotational center axis.

Description

manipulator

The present invention relates to a manipulator.
This application claims priority on May 31, 2016 based on Japanese Patent Application No. 2016-109120 for which it applied to Japan, and uses the content here.

A configuration is known in which the rotational drive of two pulleys is transmitted to a biaxial joint via a differential gear mechanism and controlled independently (for example, Patent Document 1).

Japanese Patent Publication No. 6-4230

In the differential gear mechanism as described above, force is transmitted by meshing gears rotating around each axis. Therefore, there has been a problem that the degree of freedom of arrangement of the driving shaft and the degree of freedom of arrangement of the driving device for transmitting power to the differential gear mechanism are reduced.

In view of the above problems, an aspect of the present invention provides a manipulator capable of independently controlling a plurality of rotation center shafts by a plurality of drive devices while ensuring the degree of freedom of arrangement of the rotation center shaft and the drive device. Is one of the purposes.

One aspect of the manipulator of the present invention includes a first member, a second member rotatably attached to the first member around a first rotation center axis, the first member, and the second member. Both of the first rotation member and the second rotation member rotatably attached to the first rotation center axis, and a second rotation different from the first rotation center axis with respect to the first member. A third rotating member rotatably attached around a central axis, a first driving device for rotating the first rotating member around the first rotating central axis, and the second rotating member at the first rotating central axis A first transmission that connects the second driving device that rotates around, the first rotating member, and the third rotating member, and transmits the rotation of the first rotating member to the third rotating member via tension. Connecting a member, the second rotating member, and the third rotating member A second transmission member that transmits the rotation of the second rotation member to the third rotation member via tension, and the first transmission member is connected to the first rotation center shaft by the first rotation member. When a rotational torque in one direction around is applied, a rotational torque in one direction around the second rotation center axis is transmitted to the third rotational member, and the second transmission member is the second rotational member. When a rotation torque in one direction around the first rotation center axis is applied to the third rotation member, a rotation torque in the other direction around the second rotation center axis is transmitted to the third rotation member.

According to one aspect of the present invention, there is provided a manipulator capable of independently controlling a plurality of rotation center shafts by a plurality of drive devices while ensuring the degree of freedom of arrangement of the rotation center shaft and the drive device.

It is a perspective view which shows the manipulator of 1st Embodiment. It is sectional drawing which shows the part of the manipulator of 1st Embodiment. It is a perspective view which shows the shoulder part of 1st Embodiment, and the part of a drive unit. It is a perspective view which shows the drive unit of 1st Embodiment. It is a perspective view which shows the drive unit of 1st Embodiment. It is a perspective view for demonstrating the drive method of the upper arm part by the drive unit of 1st Embodiment. It is a perspective view for demonstrating the drive method of the upper arm part by the drive unit of 1st Embodiment. It is a schematic diagram for demonstrating the principle of an example which controls three rotation center axes by three motors. It is a schematic diagram for demonstrating the principle of the other example which controls three rotation center axes by three motors. It is a schematic diagram for demonstrating the principle of the other example which controls three rotation center axes by three motors. It is a typical perspective view which shows the 1st pulley of 2nd Embodiment. It is a typical perspective view which shows the 1st pulley of 2nd Embodiment. It is a typical side view which shows the drive unit of 3rd Embodiment. It is a typical side view which shows the drive unit of 3rd Embodiment. It is a typical side view which shows the drive unit of 4th Embodiment. It is a typical side view which shows the drive unit of 4th Embodiment.

Hereinafter, a manipulator according to an embodiment of the present invention will be described with reference to the drawings. The scope of the present invention is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical idea of the present invention. In the following drawings, the scale and number of each structure may be different from the scale and number of the actual structure in order to make each configuration easy to understand.

<First Embodiment>
FIG. 1 is a perspective view showing a manipulator 1 of the present embodiment. FIG. 2 is a cross-sectional view showing a portion of the manipulator 1. FIG. 3 is a perspective view showing the shoulder 40 and the drive unit 10A. In FIG. 3, a part of the shoulder 40 is cut away. FIG. 4 is a perspective view showing the drive unit 10A.

As shown in FIG. 1, the manipulator 1 includes a shoulder 40, an upper arm 43, a forearm 46, a hand 47, and drive units 10A, 10B, and 10C. The drive unit 10 </ b> A connects the shoulder 40 and the upper arm 43, and drives the upper arm 43 with respect to the shoulder 40. The drive unit 10 </ b> B connects the upper arm portion 43 and the forearm portion 46, and drives the forearm portion 46 with respect to the upper arm portion 43. The drive unit 10 </ b> C connects the forearm portion 46 and the hand portion 47 and drives the hand portion 47 with respect to the forearm portion 46.

Since the drive units 10A to 10C basically have the same configuration, the configuration common to each unit may be described only for the drive unit 10A as a representative.

In the following description, assuming that the position and posture of the shoulder 40 are fixed, the posture of the manipulator 1 shown in FIGS. 1 to 4 is referred to as a “reference posture”. In addition, the positional relationship of each unit will be described with reference to the three-dimensional orthogonal coordinate system (XYZ coordinate system) shown in each drawing as appropriate. The Z-axis direction is a direction parallel to a second rotation center axis J2 described later. The X-axis direction is orthogonal to the Z-axis direction and is a direction parallel to one side of a bottom 41 described later of the shoulder 40. The Y-axis direction is a direction orthogonal to both the Z-axis direction and the X-axis direction.

In the following description, the Z-axis direction may be referred to as “vertical direction”, the X-axis direction may be referred to as “front-rear direction”, and the Y-axis direction may be referred to as “left-right direction”. The positive side (+ Z side) in the Z-axis direction may be referred to as “upper side”, and the negative side (−Z side) in the Z-axis direction may be referred to as “lower side”. The positive side (+ X side) in the X-axis direction may be called “front side”, and the negative side (−X side) in the X-axis direction may be called “rear side”. The positive side (+ Y side) in the Y-axis direction may be referred to as “right side”, and the negative side (−Y side) in the Y-axis direction may be referred to as “left side”. In addition, for a certain target, a side close to a second rotation center axis J2 (to be described later) in the left-right direction may be referred to as “inward in the left-right direction”. Sometimes called “outside”.

In addition, the vertical direction, the front-rear direction, the left-right direction, the upper side, the lower side, the front side, the rear side, the right side, and the left side are simply names for explaining the positional relationship of each part. There is no limitation on the mode of use and posture.

As shown in FIGS. 2 and 3, the shoulder 40 includes a bottom 41 and a side wall 42. The bottom 41 has a square plate shape. As shown in FIG. 2, a wire through hole 41 a that penetrates the bottom 41 in the vertical direction is formed in the bottom 41. Although illustration is omitted, a total of eight wire through-holes 41 a are formed, two on each of the front and rear direction sides (± X side) and the left and right direction sides (± Y side) across the center of the bottom 41. In the center of the upper surface of the bottom portion 41, a concave portion 41b recessed downward is formed. At the center of the bottom surface of the recess 41b, a bottom center through hole 41c that penetrates the bottom 41 in the vertical direction is formed.

The side wall 42 is fixed to the upper surface of the bottom 41 as shown in FIGS. The side wall portion 42 is a rectangular frame-shaped wall portion that rises upward from the outer edge of the upper surface of the bottom portion 41 and opens upward. The side wall portion 42 is provided with a tension adjusting mechanism 50 described later.

The drive unit 10A is connected to the lower side of the shoulder 40 as shown in FIGS. The drive unit 10A rotates the upper arm 43 with respect to the shoulder 40 around the first rotation center axis J1 (± θ1 direction) and the second rotation center axis J2 (± θ2 direction).

The first rotation center axis J1 is an axis parallel to the left-right direction (Y-axis direction) in the reference posture. As described above, the second rotation center axis J2 is an axis parallel to the vertical direction (Z-axis direction). In the present embodiment, the direction of the second rotation center axis J2 does not change regardless of the relative movement of each part of the manipulator 1. The second rotation center axis J2 is different from the first rotation center axis J1. In the present embodiment, the second rotation center axis J2 is an axis orthogonal to the first rotation center axis J1.

As shown in FIGS. 2 and 4, the drive unit 10 </ b> A includes a support member (first member) 20, a first motor (first drive device) 21, a second motor (second drive device) 22, 1 pulley (first rotating member) 31, second pulley (second rotating member) 32, third pulley (third rotating member) 33, central bolt 29a, and first wire (first transmission member) 81 And a second wire (second transmission member) 82 and a tension adjusting mechanism 50.

In the following description of the configuration of the drive unit 10A, the positional relationship of each part will be described on the assumption that the manipulator 1 is in the reference posture.

The support member 20 supports the first motor 21, the second motor 22, the first pulley 31, and the second pulley 32 so as to be rotatable about the first rotation center axis J1 (± θ1 direction). The support member 20 includes a first plate member 23, a second plate member 24, a third plate member 25, a bush 28, bearing holding members 26a and 26b, a first output bearing 26c, and a second output bearing 26d. A first auxiliary pulley support portion 27a, a second auxiliary pulley support portion 27b, first auxiliary pulleys 34a and 34b, and second auxiliary pulleys 35a and 35b.

The first plate member 23 includes a first pulley support portion 23a and a first upper plate portion 23b. The 1st pulley support part 23a is plate shape extended to the plane (ZX plane) orthogonal to the left-right direction. The shape of the first pulley support portion 23a viewed along the left-right direction (Y-axis direction) (hereinafter referred to as a side view) is a rectangular shape that is long in the up-down direction. The first pulley support portion 23 a is located on the outer side in the left-right direction (−Y side) with respect to the first motor 21 and the first pulley 31. As shown in FIG. 2, the first pulley support portion 23a is formed with a first output shaft through hole 23d that penetrates the first pulley support portion 23a in the left-right direction.

The first upper plate portion 23b has a plate shape extending inward in the left-right direction (+ Y side) from the upper end of the first pulley support portion 23a. The shape of the first upper plate portion 23b viewed from the upper side to the lower side (hereinafter referred to as a plan view) is a substantially rectangular shape that is long in the left-right direction (Y-axis direction). The first upper plate portion 23b is formed with a first central through hole 23c that penetrates the first upper plate portion 23b in the vertical direction. The first central through hole 23c has a circular shape passing through the second rotation center axis J2 at the center.

The second plate member 24 includes a second pulley support portion 24a and a second upper plate portion 24b. The 2nd pulley support part 24a is plate shape extended to the plane (ZX plane) orthogonal to the left-right direction. The side view shape of the second pulley support portion 24a is a rectangular shape that is long in the vertical direction. The second pulley support 24 a is located on the outer side in the left-right direction (+ Y side) than the second motor 22 and the second pulley 32. The second pulley support portion 24a is formed with a second output shaft through hole 24d that penetrates the second pulley support portion 24a in the left-right direction. The 1st pulley support part 23a and the 2nd pulley support part 24a are provided facing the left-right direction (Y-axis direction).

The second upper plate portion 24b has a plate shape extending from the upper end of the second pulley support portion 24a to the inner side in the left-right direction (−Y side). The plan view shape of the second upper plate portion 24b is a substantially rectangular shape that is long in the left-right direction (Y-axis direction). The left (−Y side) portion of the second upper plate portion 24b overlaps the right (+ Y side) portion of the first upper plate portion 23b in the vertical direction (Z-axis direction). The upper surface of the left side portion of the second upper plate portion 24b is fixed in contact with the lower surface of the right portion of the first upper plate portion 23b.

The second upper plate portion 24b is formed with a second central through hole 24c penetrating the second upper plate portion 24b in the vertical direction. The second central through hole 24c has a circular shape passing through the second rotation center axis J2 at the center. The second central through hole 24c overlaps the first central through hole 23c in the vertical direction.

The third plate member 25 is fixed to the upper surface of the first upper plate portion 23 b in the first plate member 23. As shown in FIGS. 2 and 4, the third plate member 25 has a plate shape that extends in a plane (XY plane) orthogonal to the vertical direction. The plan view shape of the third plate member 25 is a square shape.

As shown in FIG. 2, a third central through hole 25 a penetrating the third plate member 25 in the vertical direction is formed at the center of the third plate member 25. The third central through hole 25a has a circular shape concentric with the first central through hole 23c and the second central through hole 24c. The inner diameter of the third central through hole 25a is smaller than the inner diameter of the first central through hole 23c and the inner diameter of the second central through hole 24c. On the upper surface of the third plate member 25, a concave portion 25b that is recessed downward is formed. The recess 25b has an annular shape that extends radially outward from the inner edge of the third central through hole 25a.

The first plate member 23, the second plate member 24, and the third plate member 25 are fixed to each other by a bolt that penetrates each member in the vertical direction and a nut that is screwed to the lower end of the bolt.

The bush 28 includes a bush main body 28a and a flange portion 28b. The bush main body 28a is open at both ends in the vertical direction and has a cylindrical shape centered on the second rotation center axis J2. The lower part of the bush main body 28a is inserted inside the second central through hole 24c, the first central through hole 23c, and the third central through hole 25a. The bush main body 28a is fitted inside the third central through hole 25a.

The flange portion 28b has an annular shape extending from the lower end of the bush main body 28a to the radially outer side of the second rotation center axis J2. The flange portion 28b is fitted inside the first central through hole 23c and the second central through hole 24c. The upper surface of the flange portion 28 b is in contact with the lower surface of the third plate member 25.

The bearing holding members 26a and 26b are cylindrical members that open on both sides in the left-right direction (± Y side) and center on the first rotation center axis J1. The bearing holding member 26a is fixed to the outer surface in the left-right direction (−Y side) of the first pulley support portion 23a with a screw. The bearing holding member 26a has a flange portion that extends radially outward at an end portion on the first pulley support portion 23a side (+ Y side). The inner side of the bearing holding member 26a overlaps the first output shaft through hole 23d in the left-right direction (Y-axis direction).

The bearing holding member 26b is fixed to the surface on the outer side in the left-right direction (+ Y side) of the second pulley support portion 24a with a screw. The bearing holding member 26b has a flange that extends radially outward at the end on the second pulley support portion 24a side (−Y side). The inner side of the bearing holding member 26b overlaps the second output shaft through hole 24d in the left-right direction (Y-axis direction).

The first output bearing 26c has a cylindrical shape that opens on both sides in the left-right direction (± Y side) and has the first rotation center axis J1 as the center. The first output bearing 26c is provided in a hole formed by the inside of the bearing holding member 26a and the first output shaft through hole 23d. The outer peripheral surface of the first output bearing 26c is fixed to the inner peripheral surface of the bearing holding member 26a with screws.

The second output bearing 26d has a cylindrical shape that opens on both sides in the left-right direction (± Y side) and has the first rotation center axis J1 as the center. The second output bearing 26d is provided in a hole formed by the inner side of the bearing holding member 26b and the second output shaft through hole 24d. The outer peripheral surface of the second output bearing 26d is fixed to the inner peripheral surface of the bearing holding member 26b with screws.

As shown in FIGS. 2 and 4, the first auxiliary pulley support portion 27a is fixed to the left (−Y side) portion of the upper surface of the first upper plate portion 23b. As shown in FIG. 4, the first auxiliary pulley support portion 27a is a rectangular parallelepiped member that is long in the front-rear direction (X-axis direction). As shown in FIG. 2, the first auxiliary pulley support portion 27a is formed with a plurality of (six in the figure) shaft fixing holes 27c that penetrate the first auxiliary pulley support portion 27a in the front-rear direction.

The first auxiliary pulley shaft 34c is inserted and fixed in one of the plurality of shaft fixing holes 27c. The first auxiliary pulley shaft 34c has a cylindrical shape extending in the front-rear direction (X-axis direction). Both ends of the first auxiliary pulley shaft 34c in the front-rear direction protrude from the shaft fixing hole 27c.

As shown in FIG. 4, the first auxiliary pulley 34a is rotatably connected to the front (+ X side) end of the first auxiliary pulley shaft 34c. The first auxiliary pulley 34b is rotatably connected to the rear (−X side) end of the first auxiliary pulley shaft 34c. As a result, the first auxiliary pulleys 34a and 34b can rotate around the first auxiliary pulley shaft 34c independently of each other. In the present embodiment, the position where the first auxiliary pulleys 34a and 34b are provided can be easily adjusted by changing the shaft fixing hole 27c into which the first auxiliary pulley shaft 34c is inserted.

The second auxiliary pulley support portion 27b is fixed to the right side (+ Y side) portion of the upper surface of the second upper plate portion 24b, as shown in FIGS. As shown in FIG. 4, the second auxiliary pulley support portion 27b is a rectangular parallelepiped member that is long in the front-rear direction (X-axis direction). The upper surface of the second auxiliary pulley support portion 27b is located below the upper surface of the first auxiliary pulley support portion 27a. As shown in FIG. 2, the second auxiliary pulley support portion 27b is formed with a plurality (four in the figure) of shaft fixing holes 27d penetrating the second auxiliary pulley support portion 27b in the front-rear direction.

The second auxiliary pulley shaft 35c is inserted and fixed in one of the plurality of shaft fixing holes 27d. The second auxiliary pulley shaft 35c has a cylindrical shape extending in the front-rear direction (X-axis direction). Both ends of the second auxiliary pulley shaft 35c in the front-rear direction protrude from the shaft fixing hole 27d.

As shown in FIG. 4, the second auxiliary pulley 35a is rotatably connected to the front (+ X side) end of the second auxiliary pulley shaft 35c. The second auxiliary pulley 35b is rotatably connected to the rear (−X side) end of the second auxiliary pulley shaft 35c. As a result, the second auxiliary pulleys 35a and 35b can rotate around the second auxiliary pulley shaft 35c independently of each other. In the present embodiment, the position where the second auxiliary pulleys 35a and 35b are provided can be easily adjusted by changing the shaft fixing hole 27d into which the second auxiliary pulley shaft 35c is inserted.

The first motor 21 and the second motor 22 are, for example, servo motors. In the present embodiment, the first motor 21 and the second motor 22 are fixed to the upper arm portion 43. In the relationship with the drive unit 10A, the upper arm portion 43 corresponds to the second member. The first motor 21 and the second motor 22 are fixed to each other so that their output shafts face opposite sides in the left-right direction (Y-axis direction).

The first motor 21 is fixed to the left side (−Y side) of the second motor 22 as shown in FIG. The first motor 21 includes a first pulley receiving portion 21b that protrudes to the left. The first pulley receiving portion 21b has a cylindrical shape centered on the first rotation center axis J1. The first output shaft 21a of the first motor 21 extends to the left from the first pulley receiving portion 21b. The first output shaft 21a has a cylindrical shape centered on the first rotation center axis J1. The first output shaft 21a is rotatably supported inside the first output bearing 26c. Thereby, the first output shaft 21a of the first motor 21 can rotate about the first rotation center axis J1 (± θ1 direction) with respect to the support member 20.

The second motor 22 is fixed to the right side (+ Y side) of the first motor 21. The second motor 22 includes a second pulley receiving portion 22b that protrudes to the right. The second pulley receiving portion 22b has a columnar shape centered on the first rotation center axis J1. The second output shaft 22a of the second motor 22 extends to the right from the second pulley receiving portion 22b. The second output shaft 22a has a cylindrical shape with the first rotation center axis J1 as the center. That is, in the present embodiment, the first output shaft 21a of the first motor 21 and the second output shaft 22a of the second motor 22 are arranged coaxially. The second output shaft 22a is rotatably supported by the second output bearing 26d. As a result, the second output shaft 22a of the second motor 22 can rotate about the first rotation center axis J1 (± θ1 direction) with respect to the support member 20.

The first pulley 31 is disposed between the first pulley support portion 23a of the first plate member 23 and the first motor 21 in the left-right direction (Y-axis direction). The first pulley 31 is fixed to the first output shaft 21 a of the first motor 21. Thereby, the first motor 21 can rotate the first pulley 31 around the first rotation center axis J1 (± θ1 direction). The 1st pulley 31 is provided with the 1st pulley main-body part 31a, the disc part 31b, and the fixing | fixed part 31c.

The first pulley main body 31a is a cylindrical portion around which the first wire 81 is wound. The disc portion 31b is a disc-shaped portion that extends from both ends in the left-right direction of the first pulley main body portion 31a to the outside in the radial direction of the first rotation center axis J1. The fixing portion 31c is a cylindrical portion that protrudes outward in the left-right direction from the disc portion 31b on the outer side in the left-right direction (−Y side). The outer diameter of the fixing portion 31c is smaller than the outer diameter of the first pulley main body portion 31a.

The first pulley 31 is formed with a through hole that communicates with the inside of the fixed portion 31c and penetrates the first pulley 31 in the left-right direction (Y-axis direction). The first output shaft 21a passes through the through hole. Has been. The fixing portion 31c is fixed to the first output shaft 21a by tightening screws from the outer peripheral surface of the fixing portion 31c to the outer peripheral surface of the first output shaft 21a.

On the inner surface (+ Y side) of the first pulley 31 in the left-right direction, a fitting recess 31d is formed that is recessed outward in the left-right direction (−Y side). The first pulley receiving portion 21b of the first motor 21 is fitted in the fitting recess 31d. The first pulley 31 is supported by the first pulley receiving portion 21b so as to be rotatable about the first rotation center axis J1 (± θ1 direction). The first pulley 31 is attached to both the support member 20 and the upper arm portion 43 to which the first motor 21 is fixed so as to be rotatable around the first rotation center axis J1 (± θ1 direction).

The second pulley 32 is disposed between the second pulley support portion 24a of the second plate member 24 and the second motor 22 in the left-right direction (Y-axis direction). The second pulley 32 is fixed to the second output shaft 22 a of the second motor 22. Accordingly, the second motor 22 can rotate the second pulley 32 around the first rotation center axis J1 (± θ1 direction). The 2nd pulley 32 is provided with the 2nd pulley main-body part 32a, the disc part 32b, and the fixing | fixed part 32c.

The second pulley main body 32a is a cylindrical portion around which the second wire 82 is wound. The disc portion 32b is a disc-shaped portion that extends from both ends in the left-right direction of the second pulley main body portion 32a to the outside in the radial direction of the first rotation center axis J1. The fixing portion 32c is a cylindrical portion that protrudes outward in the left-right direction from the disc portion 32b on the outer side in the left-right direction (+ Y side). The outer diameter of the fixed portion 32c is smaller than the outer diameter of the second pulley main body portion 32a.

The second pulley 32 is formed with a through hole that communicates with the inside of the fixed portion 32c and penetrates the second pulley 32 in the left-right direction (Y-axis direction). The second output shaft 22a passes through the through hole. Has been. The fixing portion 32c is fixed to the second output shaft 22a by tightening a screw from the outer peripheral surface of the fixing portion 32c to the outer peripheral surface of the second output shaft 22a.

A fitting recess 32d that is recessed outward in the left-right direction (+ Y side) is formed on the inner surface (−Y side) in the left-right direction of the second pulley 32. The second pulley receiving portion 22b of the second motor 22 is fitted in the fitting recess 32d. The second pulley 32 is supported by the second pulley receiving portion 22b so as to be rotatable around the first rotation center axis J1 (± θ1 direction). The second pulley 32 is attached to both the support member 20 and the upper arm portion 43 to which the second motor 22 is fixed so as to be rotatable around the first rotation center axis J1 (± θ1 direction).

The third pulley 33 is fixed to the lower surface of the bottom 41 of the shoulder 40. More specifically, the third pulley 33 is fixed to the bottom portion 41 by tightening a screw from the bottom surface of the recess 41 b of the bottom portion 41 to the upper surface of the third pulley 33. The third pulley 33 includes an upper body part 33a, a lower body part 33b, an upper disk part 33c, a central disk part 33d, and a lower disk part 33e.

The upper body portion 33a is a portion around which the first wire 81 is wound. The upper body part 33a has a columnar shape centered on the second rotation center axis J2. The lower body part 33b is located below the upper body part 33a. The lower main body portion 33b is a portion around which the second wire 82 is wound. The lower main body portion 33b has a columnar shape centered on the second rotation center axis J2. The outer diameter of the upper body part 33a and the outer diameter of the lower body part 33b are the same.

The upper disk part 33c is a disk-shaped part that extends from the upper end of the upper body part 33a to the outside in the radial direction of the second rotation center axis J2. The upper part of the upper disk part 33 c is fitted in a recess formed in the lower surface of the bottom part 41 in the shoulder part 40.

The upper disc portion 33c is formed with a wire through hole 33f that penetrates the upper disc portion 33c in the vertical direction. Although illustration is omitted, a total of eight wire through-holes 33f are formed on each of the two sides on the front and rear direction (± X side) and the both sides in the left and right direction (± Y side) across the second rotation center axis J2. Yes. The plurality of wire through holes 33 f communicate with the plurality of wire through holes 41 a in the bottom 41. The plurality of wire through holes 33f overlap with the plurality of wire through holes 41a in the bottom portion 41 in plan view.

The central disc part 33d is located at the center in the vertical direction between the upper body part 33a and the lower body part 33b. The central disc portion 33d is a disc-shaped portion that extends outward in the radial direction of the second rotation center axis J2. The central disc portion 33d is formed with a wire through hole 33g that penetrates the central disc portion 33d in the vertical direction. Although illustration is omitted, a total of eight wire through holes 33g are formed, two on each of the front and rear direction sides (± X side) and the left and right direction sides (± Y side) across the second rotation center axis J2. Yes. The plurality of wire through holes 33g overlap with the plurality of wire through holes 33f in the upper disk portion 33c in a plan view.

The lower disk part 33e is a disk-shaped part that extends from the lower end of the lower body part 33b to the radially outer side of the second rotation center axis J2. The lower disc portion 33e is formed with a wire through hole 33h that penetrates the lower disc portion 33e in the vertical direction. Although illustration is omitted, a total of eight wire through-holes 33h are formed, two on each of the front and rear direction sides (± X side) and the left and right direction sides (± Y side) across the second rotation center axis J2. Yes. The plurality of wire through holes 33h overlap with the plurality of wire through holes 33f in the upper disk part 33c and the plurality of wire through holes 33g in the central disk part 33d in plan view.

The outer diameter of the upper disk portion 33c, the outer diameter of the central disk portion 33d, and the outer diameter of the lower disk portion 33e are, for example, the same. The upper disc portion 33c, the central disc portion 33d, and the lower disc portion 33e overlap the concave portion 25b of the third plate member 25 in plan view.

The lower surface of the third pulley 33 is formed with a concave portion 33i that is recessed upward. The shape viewed from the lower side of the concave portion 33i is a circular shape passing through the center by the second rotation center axis J2. The upper end of the bush main body 28a in the bush 28 is inserted into the recess 33i. A pulley central through hole 33j that passes through the third pulley 33 in the vertical direction is formed at the center of the top surface of the recess 33i. The plan view shape of the pulley central through hole 33j is a circular shape passing through the center through the second rotation center axis J2.

The central bolt 29a is inserted into the second central through hole 24c from the lower side of the second upper plate portion 24b in the second plate member 24. The central bolt 29a is inserted from the second central through hole 24c into the shoulder 40 through the inside of the bush 28, the pulley central through hole 33j, the bottom central through hole 41c, and the recess 41b.

The central bolt 29a is fixed to the third pulley 33 by screws tightened from the outer peripheral surface of the upper main body portion 33a of the third pulley 33 and the outer peripheral surface of the lower main body portion 33b to the outer peripheral surface of the central bolt 29a. ing. A locking nut 29d is screwed onto the upper end of the central bolt 29a.

A guide member 29b is mounted on the outer peripheral surface of the head side (-Z side) portion of the central bolt 29a. The guide member 29b has a cylindrical shape that opens at both ends in the vertical direction. The guide member 29 b is inserted inside the bush 28 and is supported so as to be rotatable with respect to the inner surface of the bush 28.

A washer 29c is provided between the head of the central bolt 29a and the guide member 29b and the bush 28 in the vertical direction. The upper surface of the washer 29 c is in contact with the lower surface of the guide member 29 b and the lower surface of the bush 28. The head of the central bolt 29a supports the bush 28 from below via a washer 29c. The lower surface of the third plate member 25 fixed to the first plate member 23 and the second plate member 24 is in contact with the upper surface of the flange portion 28 b of the bush 28. Therefore, the head of the central bolt 29a supports the support member 20 from below via the washer 29c. Thus, the shoulder 40 and the third pulley 33 and the support member 20 are connected via the central bolt 29a.

Since the bush 28 is rotatably supported with respect to the guide member 29b, the support member 20 is rotated around the second rotation center axis J2 (± θ2 direction) with respect to the central bolt 29a, the third pulley 33, and the shoulder 40. ) Can be rotated. Therefore, the third pulley 33 is attached to the support member 20 so as to be rotatable around the second rotation center axis J2.

The first wire 81 connects the first pulley 31 and the third pulley 33 as shown in FIG. The first wire 81 transmits the rotation of the first pulley 31 to the third pulley 33 via tension. The first wire 81 is, for example, a stainless steel wire. In the present embodiment, the first wire 81 includes two wires, a front first wire 81a and a rear first wire 81b.

The front side first wire 81a is wound around the first pulley 31 several times (for example, twice) and pulled out from the front side (+ X side) of the first pulley 31 to the upper side. The front first wire 81a drawn to the upper side is guided to the inner side in the left-right direction (+ Y side) by being hooked on the first auxiliary pulley 34a, and several times from the front side with respect to the upper main body portion 33a of the third pulley 33. It is wound (for example, twice).

The rear first wire 81b is wound around the first pulley 31 several times (for example, twice), and is drawn upward from the rear side (−X side) of the first pulley 31. The rear first wire 81b drawn upward is guided to the inner side in the left-right direction (+ Y side) by being hooked on the first auxiliary pulley 34b, and from the rear side with respect to the upper main body portion 33a of the third pulley 33. It is wound several times (for example, twice).

Although not shown, the front first wire 81a is arranged in the left-right direction of the first pulley 31 through two holes formed in the disk portion 31b of the first pulley 31 while being wound around the first pulley 31. Pulled out to the outside. A clamp tube is attached to the portion of the front first wire 81a that is drawn outward in the left-right direction. As a result, the front first wire 81 a is fixed to the first pulley 31. The rear first wire 81 b is fixed to the first pulley 31. The method of fixing the rear first wire 81b to the first pulley 31 is the same as that of the front first wire 81a.

As shown in FIG. 2, the end of the rear first wire 81 b on the third pulley 33 side is inside the wire through hole 33 f in the upper disk portion 33 c of the third pulley 33 and inside the wire through hole 41 a of the bottom 41. It passes through the shoulder 40. The end of the rear first wire 81b on the third pulley 33 side is wound and fixed on a winding shaft 53 (described later) of the tension adjusting mechanism 50.

Although illustration is omitted, the end portion of the front first wire 81a on the third pulley 33 side passes through wire through holes 33f and 41a different from the wire through holes 33f and 41a through which the rear first wire 81b is passed. It is pulled out inside the shoulder 40. And the edge part by the side of the 3rd pulley 33 of the front side 1st wire 81a is wound around the winding axis | shaft 53 different from the winding axis | shaft 53 around which the back side 1st wire 81b was wound, and is being fixed.

As described above, since the first wire 81 is wound around the first pulley 31 and the third pulley 33, the first wire 81 has a positive orientation around the first rotation center axis J1 around the first pulley 31. When a rotational torque in one direction (+ θ1 direction) is applied, a rotational torque in a positive direction (one direction, + θ2 direction) around the second rotation center axis J2 is transmitted to the third pulley 33.

The second wire 82 connects the second pulley 32 and the third pulley 33 as shown in FIG. The second wire 82 transmits the rotation of the second pulley 32 to the third pulley 33 via tension. The second wire 82 is, for example, a stainless steel wire. In the present embodiment, the second wire 82 includes two wires, a front second wire 82a and a rear second wire 82b.

The front second wire 82a is wound around the second pulley 32 several times (for example, twice), and is drawn upward from the front side (+ X side) of the second pulley 32. The front second wire 82a drawn upward is guided to the inner side in the left-right direction (−Y side) by being hooked on the second auxiliary pulley 35a, and from the front side to the lower main body portion 33b of the third pulley 33. It is wound several times (for example, twice).

The rear second wire 82b is wound around the second pulley 32 several times (for example, twice), and is drawn upward from the rear side (−X side) of the second pulley 32. The rear second wire 82b drawn upward is guided to the inner side in the left-right direction (−Y side) by being hooked on the second auxiliary pulley 35b, and is rearward relative to the lower main body portion 33b of the third pulley 33. It is wound several times (for example, twice) from the side.

The end of the second front wire 82 a on the second pulley 32 side is fixed to the second pulley 32. The end of the rear second wire 82 b on the second pulley 32 side is fixed to the second pulley 32. The method of fixing the front second wire 82a and the rear second wire 82b to the second pulley 32 is the same as the method of fixing the front first wire 81a to the first pulley 31.

As shown in FIG. 2, the end portion of the rear second wire 82b on the third pulley 33 side is inside the wire through hole 33g in the central disc portion 33d of the third pulley 33, and the wire through hole in the upper disc portion 33c. It passes through the inside of 33f and the wire through hole 41a of the bottom 41, and is pulled out into the shoulder 40. The end of the rear second wire 82b on the third pulley 33 side is wound around and fixed to a winding shaft 53 (described later) of the tension adjustment mechanism 50. The wire through holes 33f and 41a through which the rear second wire 82b is passed are wire through holes 33f and 41a different from the wire through holes 33f and 41a through which the first wire 81 is passed. The winding shaft 53 around which the rear second wire 82b is wound is a winding shaft 53 different from the winding shaft 53 around which the first wire 81 is wound.

Although illustration is omitted, the end portion of the front second wire 82a on the third pulley 33 side is different from the wire through holes 33g, 33f, 41a through which the rear second wire 82b is passed. It is pulled out to the inside of the shoulder 40 through 41a. And the edge part by the side of the 3rd pulley 33 of the front side 2nd wire 82a is wound around the winding axis | shaft 53 different from the winding axis | shaft 53 around which the back side 2nd wire 82b was wound, and is being fixed.

As described above, since the second wire 82 is wound around the second pulley 32 and the third pulley 33, the second wire 82 is positively oriented around the first rotation center axis J1 around the second pulley 32. When a rotational torque in the (+ θ1 direction) is applied, a rotational torque in the negative direction (the other direction, −θ2 direction) around the second rotation center axis J2 is transmitted to the third pulley 33. That is, when a rotational torque is applied to the first pulley 31 and the second pulley 32 in the same direction around the first rotation center axis J1, the rotational torque transmitted to the third pulley 33 by the first wire 81. And the direction of the rotational torque transmitted to the third pulley 33 by the second wire 82 are different from each other.

As shown in FIG. 3, four tension adjusting mechanisms 50 in the drive unit 10 </ b> A are provided on the side wall 42 of the shoulder 40. The four tension adjusting mechanisms 50 are respectively provided on the four outer surfaces of the side wall portion 42.

In the following description, the positional relationship of each part of the tension adjusting mechanism 50 will be described by taking the tension adjusting mechanism 50 provided on the outer side 42a on the front side (+ X side) of the outer side surfaces of the side wall part 42 as an example. The tension adjustment mechanism 50 includes a holding member 51, an adjustment member 52, a winding shaft 53, and a worm wheel 54.

The holding member 51 is fixed to the outer side surface 42a of the side wall portion 42 provided with the tension adjusting mechanism 50. The holding member 51 includes a fixed plate portion 51a and a holding portion 51b. The fixed plate portion 51 a has a plate shape that extends along the outer side surface 42 a of the side wall portion 42. The fixed plate portion 51a is fixed to the side wall portion 42 by screws.

The holding portion 51b is a plate that protrudes from both ends in the left-right direction (Y-axis direction) of the fixed plate portion 51a in the front-rear direction (X-axis direction) orthogonal to the outer surface 42a of the side wall portion 42 provided with the tension adjusting mechanism 50. Is. A side view shape of the holding portion 51b is a U-shape opening upward.

The adjusting member 52 includes a worm part 52a and a knob part 52b. The worm portion 52a extends in the left-right direction (Y-axis direction). A screw-shaped gear portion is formed on the outer surface of the worm portion 52a. The worm portion 52a is held by fitting both ends in the left-right direction into the opening of the holding portion 51b. The worm part 52a is rotatable around the central axis of the worm part 52a extending in the left-right direction. The knob 52b is fixed to the end of one side of the worm 52a in the left-right direction.

The winding shaft 53 extends along the front-rear direction (X-axis direction) orthogonal to the direction in which the worm portion 52a extends. The winding shaft 53 is provided inside the shoulder portion 40. The front end (+ X side) end of the winding shaft 53 penetrates the side wall portion 42 and the fixing plate portion 51a of the holding member 51 in the front-rear direction. The winding shaft 53 is rotatably held around the central axis of the winding shaft 53 extending in the front-rear direction. The rear end (−X side) of the winding shaft 53 is provided with a constricted portion with a smaller outer diameter, and the rear second wire 82b is wound and fixed to the constricted portion. ing.

The worm wheel 54 is fixed to the front (+ X side) end of the winding shaft 53. The worm wheel 54 is located on the front surface of the fixed plate portion 51a. A helical gear portion is formed on the outer surface of the worm wheel 54 and meshes with the gear portion of the worm portion 52a. Both the worm wheel 54 and the winding shaft 53 are rotatable around the central axis of the winding shaft 53.

Rotating the worm portion 52a via the knob 52b of the adjusting member 52 rotates the worm wheel 54 meshed with the worm portion 52a, and the winding shaft 53 rotates. Thereby, the tension | tensile_strength of the back side 2nd wire 82b can be enlarged by further winding up the back side 2nd wire 82b wound around the winding axis 53 around the winding axis 53. On the other hand, by rotating the winding shaft 53 in such a direction that the rear second wire 82b wound around the winding shaft 53 can be unwound, the tension of the rear second wire 82b can be reduced. In this way, the tension of the rear second wire 82b can be adjusted by the tension adjusting mechanism 50.

The front first wire 81a, the rear first wire 81b, and the front second wire 82a are wound around the winding shaft 53 of each tension adjusting mechanism 50 different from the tension adjusting mechanism 50 to which the rear second wire 82b is fixed. Is fixed. Thereby, the tension of each wire can be adjusted independently by operating each tension adjusting mechanism 50.

As shown in FIG. 1, the upper arm 43 is connected to the shoulder 40 via the drive unit 10A. The upper arm portion 43 includes an upper arm portion main body 44 and a connection portion 45. The upper arm portion main body 44 has an elongated rectangular tube shape extending in a direction orthogonal to the first rotation center axis J1. The direction in which the upper arm main body 44 extends is parallel to the second rotation center axis J4 in the drive unit 10B. The direction in which the upper arm main body 44 extends in the reference posture is the vertical direction (Z-axis direction).

As shown in FIG. 4, the first motor 21 and the second motor 22 are fixed to the upper arm main body 44. At the end of the upper arm 43 on the drive unit 10A side (+ Z side), a fork 44a is formed. The first motor 21 and the second motor 22 are sandwiched by a sandwiching portion 44a in a direction (X-axis direction) orthogonal to the output shaft of each motor, and are fixed to the upper arm main body 44. As described above, the first motor 21 and the second motor 22 are attached to the support member 20 so as to be rotatable about the first rotation center axis J1 (± θ1 direction). Therefore, the upper arm portion 43 is attached to the support member 20 so as to be rotatable around the first rotation center axis J1.

As shown in FIG. 1, four tension adjusting mechanisms 50 of the drive unit 10B are provided on the outer surface of the upper arm main body 44. Although illustration is omitted, each wire of the drive unit 10 </ b> B is wound around the winding shaft 53 of each tension adjusting mechanism 50 and fixed inside the upper arm main body 44. The connecting portion 45 is fixed on the opposite side (−Z side) of the upper arm main body 44 to the drive unit 10A. The drive unit 10 </ b> B is connected to the connection unit 45.

The drive unit 10B rotates the forearm portion 46 around the first rotation center axis J3 and the second rotation center axis J4 with respect to the upper arm portion 43. In relation to the drive unit 10B, the forearm portion 46 corresponds to a second member. In the reference posture, the first rotation center axis J3 is parallel to the first rotation center axis J1. In the reference posture, the second rotation center axis J4 is parallel to the second rotation center axis J2 and coaxial.

The forearm portion 46 is connected to the upper arm portion 43 via the drive unit 10B. The forearm 46 is an elongated rectangular tube extending in parallel with a direction orthogonal to the first rotation center axis J3 of the drive unit 10B. The direction in which the forearm 46 extends is a direction parallel to the second rotation center axis J6 in the drive unit 10C. The direction in which the forearm portion 46 extends in the reference posture is the front-rear direction (X-axis direction).

Four tension adjusting mechanisms 50 of the drive unit 10 </ b> C are provided on the outer surface of the forearm portion 46. The four tension adjusting mechanisms 50 are arranged side by side along the direction in which the forearm portion 46 extends (X-axis direction). Although illustration is omitted, each wire of the drive unit 10 </ b> C is wound around the winding shaft 53 of each tension adjusting mechanism 50 and fixed inside the forearm portion 46.

The drive unit 10C rotates the hand portion 47 about the first rotation center axis J5 and the second rotation center axis J6 with respect to the forearm portion 46. In the reference posture, the first rotation center axis J5 is parallel to the first rotation center axis J1. In the reference posture, the second rotation center axis J6 is perpendicular to the second rotation center axis J2.

FIG. 5 is a perspective view showing the drive unit 10C. FIG. 5 shows a case where the hand portion 47 is rotated around the first rotation center axis J5 from the reference posture. In FIG. 5, the illustration of the hand portion 47 is omitted. Further, in the drive unit 10C shown in FIG. 5, the same reference numerals are given to the same configurations as those of the drive unit 10A.

As shown in FIG. 5, the drive unit 10C is different from the drive unit 10A in the arrangement of the motors. In the drive unit 10C, the first motor 121 and the second motor 122 are overlapped and fixed to each other in a direction orthogonal to the first rotation center axis J5. The output shaft of the first motor 121 and the output shaft of the second motor 122 are parallel to the first rotation center axis J5. The output shaft of the first motor 121 and the output shaft of the second motor 122 are disposed at positions different from each other, and are disposed at positions different from the first rotation center axis J5. A first output pulley 121 a is fixed to the output shaft of the first motor 121. A second output pulley 122 a is fixed to the output shaft of the second motor 122.

The drive unit 10C further includes motor clamping members 124a and 124b and a connection member 124c. The motor clamping members 124a and 124b have a plate shape that extends in a direction orthogonal to the first rotation center axis J5. The motor clamping member 124a and the motor clamping member 124b fix the first motor 121 and the second motor 122 so as to be sandwiched in a direction parallel to the first rotation center axis J5. The connection member 124c connects the motor holding member 124a and the motor holding member 124b.

The first pulley 131 of the drive unit 10C is connected to the motor holding member 124a so as to be rotatable around the first rotation center axis J5. The second pulley 132 of the drive unit 10C is connected to the motor holding member 124b so as to be rotatable around the first rotation center axis J5.

The first wire 181 of the drive unit 10C is wound around and fixed to the first output pulley 121a several times (for example, twice), and then is pulled out from the first output pulley 121a and the first pulley 131 and the first auxiliary pulley 34a. , 34b and wound around the third pulley 33 to be fixed. Thus, the first pulley 131 is rotated around the first rotation center axis J5 by the first motor 121, and the rotation of the first pulley 131 is transmitted to the third pulley 33 by the first wire 181. The first wire 181 is composed of, for example, two wires, similarly to the first wire 81 of the drive unit 10A.

The second wire 182 of the drive unit 10C is wound around and fixed to the second output pulley 122a several times (for example, twice), and then is pulled out from the second output pulley 122a and the second pulley 132 and the second auxiliary pulley 35a. , 35b and wound around the third pulley 33 to be fixed. Accordingly, the second pulley 132 is rotated around the first rotation center axis J5 by the second motor 122, and the rotation of the second pulley 132 is transmitted to the third pulley 33 by the second wire 182. Similar to the second wire 82 of the drive unit 10A, the second wire 182 is composed of, for example, two wires.

The hand portion 47 is connected to the forearm portion 46 through the drive unit 10C as shown in FIG. The hand portion 47 is fixed to the first motor 121, the second motor 122, and the motor holding members 124a and 124b in the drive unit 10C. In relation to the drive unit 10C, the hand portion 47, the motor clamping members 124a and 124b, and the connection member 124c correspond to a second member.

Next, a method for driving the upper arm 43 by the drive unit 10A will be described. 6 and 7 are perspective views for explaining a method of driving the upper arm portion 43 by the drive unit 10A. FIG. 6 shows a case where the upper arm 43 is rotated around the second rotation center axis J2 with respect to the shoulder 40 from the reference posture. FIG. 7 shows a case where the upper arm 43 is rotated around the first rotation center axis J1 with respect to the shoulder 40 from the reference posture.

When the upper arm 43 is rotated around the second rotation center axis J2 (± θ2 direction) with respect to the shoulder 40, the first pulley 31 is driven by the first motor 21 and the second motor 22, as shown in FIG. And a rotational torque in the opposite direction around the second rotation center axis J <b> 2 is applied to the second pulley 32. Thereby, rotational torque is applied to the third pulley 33 in the same direction around the second rotation center axis J <b> 2 via the first wire 81 and the second wire 82. Accordingly, the support member 20 and the third pulley 33 rotate relatively around the second rotation center axis J2. In the present embodiment, since the position of the shoulder 40 to which the third pulley 33 is fixed is fixed, the support member 20 rotates around the second rotation center axis J2 with respect to the third pulley 33. Accordingly, the upper arm 43 can be rotated around the second rotation center axis J2 with respect to the shoulder 40.

Specifically, in the example of FIG. 6, the first motor 21 applies a rotational torque in the positive direction (+ θ1 direction) around the first rotation center axis J <b> 1 to the first pulley 31, and the second motor 22 applies to the second pulley 32. A rotational torque in the negative direction (-θ1 direction) around the first rotation center axis J1 is applied. In this case, rotational torque is applied to the third pulley 33 in a positive direction (+ θ2 direction) around the second rotation center axis J2. However, since the position of the third pulley 33 is fixed in this embodiment, the support member 20 is opposite to the direction of the rotational torque applied to the third pulley 33 with respect to the third pulley 33 (−θ2 direction). ).

When the upper arm 43 is rotated about the first rotation center axis J1 (± θ1 direction) with respect to the shoulder 40, the first pulley 31 is driven by the first motor 21 and the second motor 22 as shown in FIG. And a rotational torque in the same direction is applied to the second pulley 32. Thereby, the rotational torques around the second rotation center axis J2 applied to the third pulley 33 via the first wire 81 and the second wire 82 are opposite to each other. Therefore, when the absolute values of the rotational torque transmitted to the third pulley 33 by the first wire 81 and the second wire 82 are the same, the rotational torques cancel each other, and the third pulley 33 and the support member 20 Does not rotate around the center axis J2.

In this case, the rotational torque applied to the first pulley 31 and the second pulley 32 is applied to the third pulley 33 around the first rotation center axis J1 (± θ1 direction) via the first wire 81 and the second wire 82. ). Therefore, the third pulley 33, the first motor 21, and the second motor 22 rotate relatively around the first rotation center axis J1. In the present embodiment, since the position of the third pulley 33 is fixed, the first motor 21 and the second motor 22 rotate with respect to the third pulley 33. Thereby, the upper arm 43 can be rotated around the first rotation center axis J1 with respect to the shoulder 40.

Specifically, in the example of FIG. 7, the first motor 21 and the second motor 22 are in the negative direction (−θ1 direction) around the first rotation center axis J1 to the first pulley 31 and the second pulley 32. Rotating torque is applied. The rotational torque by the first motor 21 and the rotational torque by the second motor 22 are the same. In this case, a negative rotational torque around the first rotation center axis J1 is applied to the third pulley 33. However, since the position of the third pulley 33 is fixed in this embodiment, the first motor 21 and the second motor 22 rotate in the direction opposite to the direction of the rotational torque applied to the third pulley 33 (+ θ1 direction). .

The relationship between the rotational torque of each pulley applied by each motor described above and the rotational torque around each rotational center axis is expressed by the following equation (1). τ ₁ is the rotational torque of the first pulley 31 applied by the first motor 21. τ ₂ is the rotational torque of the second pulley 32 applied by the second motor 22. T ₁ is the rotational torque around the first rotation center axis J1. T ₂ are a rotation torque around the second rotation axis J2.

Here, if each coefficient a ₁₁ to a ₂₂ is 1, the rotational torque applied to each rotation center axis is expressed by the following equations (2) and (3).

From equations (2) and (3), when the absolute values of the rotational torques τ ₁ and τ ₂ are the same, the direction of the rotational torque τ ₁ of the first pulley 31 and the direction of the rotational torque τ ₂ of the second pulley 32 are the same. if, it can be seen that the rotational torque T ₂ are 0 around the second rotation axis J2. Further, it can be seen that rotational torque T ₁ of the around the first rotation center axis J1 is twice the rotational torque of the pulleys. Further, if the direction of the rotational torque τ ₁ of the first pulley 31 and the direction of the rotational torque τ ₂ of the second pulley 32 are reversed, the rotational torque T ₁ around the first rotational center axis J ₁ becomes 0, and it can be seen that the rotational torque T ₂ of the around 2 rotation axis J2 is two times the torque of each pulley.

Further, for example, a rotational torque tau ₁ of the first pulley 31 if one zero of the torque tau ₂ of the second pulley 32, around the first rotation center axis J1 and around the second rotation axis J2 Rotational torque can be applied to both. In this case, the upper arm portion 43 rotates around the first rotation center axis J1 with respect to the shoulder portion 40 and simultaneously rotates around the second rotation center axis J2. In this case, the pulley having a rotational torque of 0 is moved around the first rotation center axis J1 together with the motor while maintaining the relative positional relationship around the first rotation center axis J1 with the motor driving the pulley. Rotate.

As described above, according to the present embodiment, the driving force of the two motors can be distributed around the two rotation center axes of the first rotation center axis J1 and the second rotation center axis J2. The rotation around the first rotation center axis J1 and the rotation around the second rotation center axis J2 can be controlled independently. Further, the rotation of the first pulley 31 and the rotation of the second pulley 32 driven by each motor are transmitted to the third pulley 33 by a wire via tension. Therefore, regardless of the arrangement relationship between the first rotation center axis J1 and the second rotation center axis J2 and the position where the first motor 21 and the second motor 22 are arranged, the driving force of each motor is applied to each rotation center axis. Easy to transmit and dispense. Therefore, according to the present embodiment, it is possible to obtain the manipulator 1 that can independently control the plurality of rotation center axes by the plurality of motors while ensuring the degree of freedom of arrangement of the rotation center axis and the motor.

Also, for example, in a conventional manipulator, when an arm such as the upper arm is rotated around the rotation center axis, one motor is installed for each rotation center axis. Therefore, the rotational torque that can be applied around one rotation center axis depends on the output of one motor, and in order to apply a large torque around the rotation center axis, for example, the output is increased by enlarging the motor. It was necessary to enlarge.

On the other hand, according to this embodiment, since the driving force of two motors can be used for rotation around one rotation center axis, even when the same number of motors of the same size as in the past are arranged, The output around one rotation center axis can be doubled. Therefore, the output of the manipulator 1 can be increased. On the other hand, when the output of the manipulator 1 is the same as the conventional output, the output of each motor can be reduced, so that the motor can be reduced in size.

In addition, when the driving force of each motor is transmitted by a gear, when a large external force is applied to the manipulator, the gear may be damaged by a load applied by the external force. On the other hand, according to the present embodiment, the driving force of the first motor 21 and the driving force of the second motor 22 are transmitted by the first wire 81 and the second wire 82. Therefore, when a large external force is applied to the manipulator 1, the first wire 81 and the second wire 82 expand and contract, and the load applied by the external force can be absorbed. Thereby, it can suppress that 10A of drive units are damaged, and the highly reliable manipulator 1 is obtained.

In the above-described embodiment, the configuration is such that two rotation center axes are controlled by two motors in one drive unit, but the present invention is not limited to this. In one drive unit, two or more rotation center axes may be controlled by two motors, or two rotation center axes may be controlled by three or more motors. Moreover, it is good also as a structure which controls three or more rotation center axes in one drive unit with three or more motors.

FIG. 8 is a schematic diagram for explaining an example principle of controlling three rotation central axes by three motors. In FIG. 8, an example of controlling three rotation central axes by three motors is shown as a link manipulator LM1 to which four links are connected. As shown in FIG. 8, the link manipulator LM1 includes three motors MA, MB, and MC, a base link BL, a first link L1, a second link L2, and a third link L3. The base link BL and the first link L1 are connected to each other so as to be rotatable around the rotation center axis JA. The first link L1 and the second link L2 are connected to each other so as to be rotatable around the rotation center axis JB. The second link L2 and the third link L3 are connected to each other so as to be rotatable around the rotation center axis JC. In the link manipulator LM1, the three motors MA, MB, and MC are fixed to the base link BL. The rotation center axes JA, JB, and JC are parallel to each other.

Consider the case where the rotation center axis JA, the rotation center axis JB, and the rotation center axis JC are independently controlled by the motor MA, the motor MB, and the motor MC. In this case, as an example, the wires WA1 and WA2 driven by the motor MA, the wires WB1 and WB2 driven by the motor MB, and the wires WC1 and WC2 driven by the motor MC include the links and the rotation center shafts. On the other hand, as shown in FIG.

The wires WA1 and WA2 are fixed to the motor MA and the third link L3. The wires WB1 and WB2 are fixed to the motor MB and the third link L3. The wires WC1 and WC2 are fixed to the motor MC and the third link L3. More specifically, each wire is fixed to a pulley that is rotated by receiving torque from each motor. Each wire is fixed to the base link BL via each motor. In FIG. 8, each wire passing around each rotation center axis indicates that a rotation torque can be applied to each rotation center axis.

Specifically, for example, when the wire WA1 passing above the rotation center axis JA moves to the right in FIG. 8, a rotation torque is applied to the rotation center axis JA in the clockwise direction. On the other hand, when the wire WA2 passing below the rotation center axis JA moves rightward in FIG. 8, a rotation torque is applied to the rotation center axis JA in the counterclockwise direction.

In the case of FIG. 8, the rotational torque of each pulley applied by each motor and the rotational torque around each rotational center axis are expressed by the following equation (4). τ _A is the rotational torque of the pulley applied by the motor MA. τ _B is the rotational torque of the pulley applied by the motor MB. τ _C is the rotational torque of the pulley applied by the motor MC. T _A is the rotational torque around the rotation center axis JA. T _B is the rotational torque around the rotation center axis JB. T _C is the rotational torque around the rotation center axis JC.

Here, if each coefficient a ₁₁ to a ₃₃ is 1, the rotational torque applied to each rotation center axis is expressed by the following equations (5) to (7).

From the equations (5) to (7), when the absolute values of the rotational torques τ _A and τ _C are the same, the rotational torque τ _{B is set} to 0 and the direction of the rotational torque τ _{A and} the direction of the rotational torque τ _C are reversed. if the rotational torque T _B of the rotational torque T _a and the rotational center axis JB of the rotation center axis JA is understood to be a zero. Further, it can be seen that the absolute value of the rotational torque T _C of the rotation center axis JC is twice the torque τ _A, τ _C. Thereby, rotational torque can be applied only around the rotation center axis JC. In this case, only the third link L3 can be driven to rotate around the rotation center axis JC with respect to the second link L2. Similarly, the other rotation center axes can be controlled independently, and each link can be driven independently. Based on the above formula (4), the manipulator 1 described above can be expanded to a manipulator capable of controlling three rotation center axes by three motors by increasing the number of motors, pulleys, and rotation center axes.

Specifically, the wires WA1 and WA2 between the rotation center axis JA and the rotation center axis JB and the wires WB1 and WB2 between the rotation center axis JB and the rotation center axis JC are added to the rotation center axis. In order to reverse the direction of the rotational torque, a location where the wire handling intersects is provided. As a result, like the coefficient a ₂₂ in the expression (1) and the coefficients a ₂₂ and a ₃₃ in the expression (4), there are places where the coefficient in the coefficient matrix is attached with a minus sign. Independent control is possible.

The arrangement relationship between the motors MA, MB, MC and the rotation center axes JA, JB, JC described above can be changed as appropriate without changing the fixed relationship of each wire to each link. 9 and 10 are schematic diagrams for explaining the principle of another example in which three rotation central axes are controlled by three motors.

The link manipulator LM2 shown in FIG. 9 differs from the link manipulator LM1 shown in FIG. 8 in that the axis of the motor MA, that is, the rotation axis of the pulley rotated by the motor MA coincides with the rotation center axis JA. The motor MA is fixed to the base link BL. The other configuration of the link manipulator LM2 is the same as that of the link manipulator LM1 shown in FIG. Also in the link manipulator LM2, the rotational torque of each pulley applied by each motor and the rotational torque around each rotation center axis are expressed by the above-described equation (4).

The link manipulator LM3 shown in FIG. 10 is different from the link manipulator LM2 shown in FIG. 9 in that the axis of the motor MB, that is, the rotation axis of the pulley rotated by the motor MB coincides with the rotation center axis JB. That is, the difference is that the rotation axis of the pulley rotated by the motor MC coincides with the rotation center axis JC.

In the link manipulator LM3, the motor MB is fixed to the second link L2, and the motor MC is fixed to the third link L3. The wires WB1 and WB2 are directly fixed to the third link L3 and the base link BL. The wires WB1 and WB2 are each wound around a motor MB, more specifically, a pulley rotated by the motor MB, and connected to the motor MB. Thus, the wires WB1 and WB2 can be driven by the motor MB. By winding the wires WB1 and WB2 around the motor MB, the wires WB1 and WB2 bend when the relative posture of each link changes and the path length around which the wires WB1 and WB2 are routed changes. Can be suppressed.

The wires WC1 and WC2 are fixed to a motor MC, more specifically, a pulley and a base link BL that are rotated by the motor MC. The other configuration of the link manipulator LM3 is the same as that of the link manipulator LM2 shown in FIG. Also in the link manipulator LM3, the rotational torque of each pulley applied by each motor and the rotational torque around each rotation center axis are expressed by the above-described equation (4).

When the motors MA, MB, and MC are fixed to the base link BL like the link manipulator LM1 shown in FIG. 8 and the link manipulator LM2 shown in FIG. 9, the first link L1 is fixed by fixing the base link BL. When driving the second link L2 and the third link L3, it is not necessary to compensate the own weights of the motors MA, MB, MC by the motors MA, MB, MC. Therefore, the rotational torque of each motor MA, MB, MC for driving each link can be reduced.

Further, when the motor MA is made to coincide with the rotation center axis JA like the link manipulator LM2 shown in FIG. 9, the lengths of the wires WA1 and WA2 can be made shorter than the link manipulator LM1 shown in FIG. Therefore, the expansion / contraction amount of the wires WA1 and WA2 as a whole can be reduced, and the driving force can be accurately transmitted to each link via the wires WA1 and WA2. Thereby, the error of the position of each link to drive can be made small, and each link can be driven with sufficient position accuracy. When each motor is arranged on each rotation center axis like the link manipulator LM3 shown in FIG. 10, the total length of each wire can be easily shortened, and the expansion / contraction amount of each wire can be reduced. Therefore, each link can be driven with higher positional accuracy.

Further, as in the link manipulator LM3 shown in FIG. 10, when the motors are arranged on the links, the wire handling is difficult to be complicated, and the mechanism for driving the links is easily unitized.

As examples of controlling the three rotation center axes by three motors, in addition to the examples shown in FIGS. 8 to 10, for example, the motor MB is shown in FIG. 8 for the link manipulator LM3 shown in FIG. The link manipulator which only the point fixed to the base link BL similarly to the link manipulator LM1 shown can also be mentioned.

By increasing the number of rotation center axes that can be controlled based on the principle shown by taking each of the link manipulators LM1, LM2, LM3 as an example, for example, the number of rotation centers equal to the number of joints of the human arm (26 axes) It is also possible to extend the configuration in which the shafts are interfered with each other by wires and the rotation is controlled using a plurality of motors. Therefore, the manipulator 1 of the present embodiment is particularly useful when applied to an artificial hand, an arm of a humanoid robot, and the like.

In addition, in FIGS. 8 to 10, each of the wires WA1 and WA2 may be configured by a single wire. Each of the wires WB1 and WB2 may be composed of a single wire. Each of the wires WC1 and WC2 may be composed of a single wire.

Further, according to the present embodiment, the driving force of each motor is transmitted and distributed to a plurality of rotation center axes using pulleys and wires. Therefore, it is possible to incorporate a load sensitive mechanism that can increase the output around the rotation center axis as the load on the first motor 21 and the load on the second motor 22 increase. Details will be described in the second to fourth embodiments described later.

Further, for example, when the manipulator 1 is an articulated manipulator as in the present embodiment, if a plurality of motors that drive each joint are collectively arranged at the same location, the handling of the wire is more complicated as the number of joints increases. There was a problem.

On the other hand, according to the present embodiment, the first motor 21 and the second motor 22 are fixed to the upper arm portion 43. Therefore, the device that drives the upper arm 43 with respect to the shoulder 40 can be unitized as the drive unit 10A. Thus, by connecting the two objects to be relatively driven by the drive unit 10A, the two objects can be easily driven relatively with a degree of freedom of the number of rotation center axes of the drive unit 10A. Moreover, since the handling of each wire is completed within the drive unit 10A, the handling of the wires does not become complicated even if the number of joints of the manipulator is increased. Therefore, it is easy to increase the number of joints of the manipulator, and it is easy to add joints.

The articulated manipulator as described above can be used as a manipulator that performs work in a narrow place, for example. As an example, a manipulator that conducts pipe inspection through a pipe, a manipulator that conducts exploration / search by entering a gap between rubbles at a disaster site, and the like. The manipulator 1 of the present embodiment is particularly useful when applied to such an articulated manipulator.

For example, consider the case where the manipulator 1 is used as a prosthetic hand. In this case, for example, when the first motor 21 and the second motor 22 are attached to the shoulder 40 to be fixed, each motor becomes an obstacle when connecting the shoulder 40 to the user's body, and the user's It is difficult to wear a prosthetic hand on the body.

On the other hand, according to the present embodiment, the first motor 21 and the second motor 22 are fixed to the upper arm portion 43 driven with respect to the shoulder portion 40, and the first motor 21 and the second motor 22 are changed together with the change in the posture of the upper arm portion 43. The motor 21 and the second motor 22 move. Therefore, the motor is not fixed to the shoulder 40, and when using the manipulator 1 as a prosthetic hand, it is easy to connect the shoulder 40 to the user's body. Therefore, the manipulator 1 of the present embodiment is particularly useful when used as a prosthetic hand.

Further, in the drive unit 10A of the present embodiment, the first output shaft 21a of the first motor 21 and the second output shaft 22a of the second motor 22 are centered on the first rotation center axis J1. Therefore, the output of the first motor 21 can be directly transmitted to the first pulley 31 by fixing the first pulley 31 to the first output shaft 21a. Similarly, the output of the second motor 22 can be directly transmitted to the second pulley 32 by fixing the second pulley 32 to the second output shaft 22a. Thereby, the output of the first motor 21 and the output of the second motor 22 can be easily transmitted to the first pulley 31 and the second pulley 32.

In the drive unit 10 </ b> C of the present embodiment, the output shaft of the first motor 121 and the output shaft of the second motor 122 are arranged so as to be shifted from the first rotation center axis J <b> 5, and the first motor 121 and the second motor 122. Are stacked in a direction perpendicular to the first rotation center axis J5. Thereby, the dimension of the direction parallel to the 1st rotation central axis J5 between the 1st pulley 131 and the 2nd pulley 132 can be made small. Thereby, the dimension of the drive unit 10C in the direction parallel to the first rotation center axis J5 can be reduced, and the drive unit 10C can be easily downsized.

Further, according to the present embodiment, the tension adjusting mechanism 50 that adjusts the tension of the first wire 81 and the tension of the second wire 82 is provided. As a result, even if the first wire 81 and the second wire 82 are loosened and the tension of the first wire 81 and the tension of the second wire 82 are lowered, the first wire 81 and the second wire 82 Tension can be applied. Further, by adjusting the tension of the first wire 81 and the tension of the second wire 82, the advance angle or delay angle of the rotation around each rotation center axis with respect to the rotation of the first motor 21 and the rotation of the second motor 22 is adjusted. can do.

Note that the present invention is not limited to the above-described embodiment, and other configurations may be employed. In the following description, the same configurations as those described above may be omitted by appropriately attaching the same reference numerals.

The first wire 81 that connects the first pulley 31 and the third pulley 33 may be, for example, a single wire. In this case, the first wire 81 may only be wound around each pulley and may not be directly fixed to the pulley. The first wire 81 may be composed of three or more wires. The second wire 82 that connects the second pulley 32 and the third pulley 33 may be, for example, a single wire. In this case, the second wire 82 may only be wound around each pulley and may not be fixed directly to the pulley. The second wire 82 may be composed of three or more wires.

Also, the transmission member is not particularly limited as long as it can transmit rotation between pulleys via tension. The transmission member may be a rope, a chain, or a belt. Moreover, the material of the transmission member is not particularly limited.

Further, the rotating member is not particularly limited as long as it is rotatably attached to each part, and may not be a pulley.

Further, the arrangement of the first motor 21 and the arrangement of the second motor 22 are not particularly limited, and the first motor 21 and the second motor 22 may be fixed at a place other than the upper arm portion 43.

The tension adjusting mechanism 50 is not particularly limited as long as the tension of the first wire 81 or the tension of the second wire 82 can be adjusted. Further, the tension adjusting mechanism 50 may be provided for only one of the first wire 81 and the second wire 82.

Further, in the drive unit 10C, the wire connecting the first output pulley 121a and the first pulley 131 may be a wire different from the first wire 181. The wire connecting the second output pulley 122 a and the second pulley 132 may be a wire different from the second wire 182.

Further, the relationship between the first rotation center axis J1 and the second rotation center axis J2 is not particularly limited as long as they are different from each other. For example, the first rotation center axis J1 and the second rotation center axis J2 may intersect each other without being orthogonal, may be in a twisted position, or may be parallel to each other.

Further, for example, each wire of the drive unit 10A may be wound around each pulley of the drive unit 10B, and each wire of the drive unit 10B may be wound around each pulley of the drive unit 10A to interfere with each other. Thereby, it can be set as the structure which controls four rotation center axes with four motors. Further, the drive units 10A to 10C may interfere with each other.

Second Embodiment
The second embodiment is different from the first embodiment in that a variable mechanism 230 as a load sensitive mechanism is provided. 11 and 12 are perspective views showing the first pulley 231 of the present embodiment.

As shown in FIGS. 11 and 12, the first pulley 231 includes a first disc portion 231a, a second disc portion 231b, a support shaft 231c, a compression spring 231d, and a connecting wire 231e. Yes. In this embodiment, each part of the first pulley 231 constitutes a variable mechanism 230.

The first disc portion 231a and the second disc portion 231b have a disc shape that extends radially outward from the first rotation center axis J1 around the first rotation center axis J1. The first disc portion 231a and the second disc portion 231b are arranged to face each other in a direction parallel to the first rotation center axis J1.

The support shaft 231c has a cylindrical shape that extends in the axial direction of the first rotation center axis J1 with the first rotation center axis J1 as the center. One end of the support shaft 231c is fixed to the first disc portion 231a. The second disk portion 231b is connected to the other end side of the support shaft 231c so as to be movable in the axial direction of the first rotation center axis J1 with respect to the support shaft 231c.

The compression spring 231d is disposed between the first disc portion 231a and the second disc portion 231b. A support shaft 231c is passed inside the compression spring 231d. One end of the compression spring 231d is in contact with the surface of the first disc portion 231a on the second disc portion 231b side. The other end of the compression spring 231d is in contact with the surface of the second disc portion 231b on the first disc portion 231a side. The compression spring 231d is oriented so as to separate the first disc portion 231a and the second disc portion 231b from the first disc portion 231a and the second disc portion 231b in the axial direction of the first rotation center axis J1. Is adding power.

The connecting wire 231e is a wire that connects the first disc portion 231a and the second disc portion 231b between the first disc portion 231a and the second disc portion 231b. A plurality of connecting wires 231e are provided along the circumferential direction of the first rotation center axis J1. The plurality of connecting wires 231e surround the first rotation center axis J1 in the circumferential direction. The diameter of the connecting wire 231e is larger than the diameter of the first wire 81, for example.

In the present embodiment, the first pulley main body of the first pulley 231 is constituted by a plurality of connecting wires 231e. That is, in the present embodiment, the first wire 81 is wound around the outside of the bundle of the plurality of connecting wires 231e.

Here, FIG. 11 shows a case where the load of the first motor 21 is relatively small and the tension of the first wire 81 is relatively small. FIG. 12 shows a case where the load of the first motor 21 is relatively large and the tension of the first wire 81 is relatively large.

When the tension of the first wire 81 becomes relatively large, the tightening force of the first wire 81 wound around the bundle of the connecting wires 231e increases. Thereby, as shown in FIG. 12, the connecting wire 231e bends and the diameter D1 of the 1st pulley 231 becomes small. The diameter D1 of the first pulley 231 corresponds to the inner diameter of the wound first wire 81. In addition, while the connecting wire 231e bends, the 2nd disc part 231b moves in the direction which approaches the 1st disc part 231a.

When the tension of the first wire 81 is relatively small, the tightening force of the first wire 81 is small. As a result, as shown in FIG. 11, the second disc portion 231b is moved away from the first disc portion 231a by the compression spring 231d, and the connecting wire 231e is stretched. Therefore, the diameter D1 of the first pulley 231 is increased.

As described above, the first pulley 231 of the present embodiment includes the variable mechanism 230 that decreases the diameter D1 of the first pulley 231 as the tension of the first wire 81 increases.

According to this embodiment, when the load of the first motor 21 is increased and the tension of the first wire 81 is increased, the diameter D1 of the first pulley 231 is decreased. Therefore, the ratio between the diameter D1 of the first pulley 231 and the diameter of the third pulley 33 is increased, and the reduction ratio between the first pulley 231 and the third pulley can be increased. Therefore, a load sensitive mechanism that can increase the output around the second rotation center axis J2 as the load of the first motor 21 increases is obtained.

The variable mechanism 230 may be provided on the second pulley 32. Thereby, the diameter of the second pulley 32 can be changed according to the load of the second motor 22. The variable mechanism 230 may be provided in both the first pulley 31 and the second pulley 32, or may be provided in only one of them.

Further, for example, the second disk portion 231b may be connected to the support shaft 231c so as to be rotatable around the first rotation center axis J1 with respect to the first disk portion 231a. In this case, when the tension of the first wire 81 is increased, the diameter D1 of the first pulley 231 may be decreased by rotating the second disk portion 231b and tilting the connecting wire 231e. At this time, the connecting wire 231e may be bent or may not be bent.

Also, instead of the connecting wire 231e, the first disc portion 231a and the second disc portion 231b may be connected using an articulated link.

Further, instead of the variable mechanism 230 described above, for example, a configuration may be used in which the diameter D1 of the first pulley 231 is changed using a spiral spring.

<Third Embodiment>
The third embodiment is different from the first embodiment in that moving mechanisms 390a and 390b as load sensitive mechanisms are provided. FIGS. 13 and 14 are schematic side views of the drive unit 310 according to the present embodiment as viewed from the left side (−Y side) to the right side (+ Y side).

The drive unit 310 includes moving mechanisms 390a and 390b as shown in FIGS. The moving mechanism 390a is provided on the front side (+ X side) of the support member 20. The moving mechanism 390a includes a movable pulley 391a and a tension spring 392a. The movable pulley 391 a is provided so as to be movable with respect to the support member 20. A front first wire 81a is hung on the movable pulley 391a. The movable pulley 391a is in contact with the front first wire 81a from the front side.

The tension spring 392a connects the movable pulley 391a and the support member 20. The tension spring 392a extends diagonally forward and downward from the support member 20, and a movable pulley 391a is connected to the tip. The tension spring 392a applies a force that is obliquely upward to the movable pulley 391a. Thereby, the movable pulley 391a is pressed against the front first wire 81a from the front side.

The moving mechanism 390b is provided on the rear side (−X side) of the support member 20. The moving mechanism 390b includes a movable pulley 391b and a tension spring 392b. The movable pulley 391 b is provided so as to be movable with respect to the support member 20. A rear first wire 81b is hung on the movable pulley 391b. The movable pulley 391b is in contact with the rear first wire 81b from the rear side.

The tension spring 392b connects the movable pulley 391b and the support member 20. The tension spring 392b extends rearward and obliquely downward from the support member 20, and a movable pulley 391b is connected to the tip. The tension spring 392b applies a forward oblique upward force to the movable pulley 391b. Accordingly, the movable pulley 391b is pressed against the rear first wire 81b from the rear side.

Here, FIG. 13 shows a case where the load of the first motor 21 is relatively small and the tension of the first wire 81 is relatively small. FIG. 14 shows a case where the load of the first motor 21 is relatively large and the tension of the first wire 81 is relatively large.

When the tension of the first wire 81 becomes relatively large, the movable pulley 391a and the movable pulley 391b are moved by the tension of the first wire 81 as shown in FIG. The movable pulley 391a moves forward and obliquely downward. The movable pulley 391b moves rearward and obliquely downward. As a result, the front first wire 81a pushed from the front side (+ X side) to the movable pulley 391a moves to the front side, and the rear first wire 81b pushed from the rear side (−X side) to the movable pulley 391b. Moves to the back side. As a result, the front first wire 81a and the rear first wire 81b move away from the second rotation center axis J2.

When the tension of the first wire 81 becomes relatively small, as shown in FIG. 13, the movable pulley 391a is moved obliquely upward rearward by the elastic force of the tension spring 392a, and the movable pulley 391b is moved forward by the elastic force of the tension spring 392b. Move diagonally upward. Thereby, the front first wire 81a is pushed by the movable pulley 391a and moved to the rear side (−X side), and the rear first wire 81b is pushed by the movable pulley 391b and moved to the front side (+ X side). Therefore, the front first wire 81a and the rear first wire 81b move in a direction approaching the second rotation center axis J2.

As described above, the moving mechanisms 390a and 390b move the first wire 81 to a position away from the second rotation center axis J2 as the tension of the first wire 81 increases.

According to the present embodiment, as the tension of the first wire 81 increases, the first wire 81 moves away from the second rotation center axis J2. Therefore, the second rotation center axis applied to the support member 20 via the first wire 81. The moment arm of the rotational moment around J2 can be increased. Therefore, a load sensitive mechanism that can increase the output around the second rotation center axis J2 as the load of the first motor 21 increases is obtained.

<Fourth embodiment>
The fourth embodiment differs from the third embodiment in the configuration of a moving mechanism as a load sensitive mechanism. 15 and 16 are schematic side views of the drive unit 410 according to this embodiment as viewed from the left side (−Y side) to the right side (+ Y side).

In this embodiment, the first wire 481 includes a front first wire 81a and a rear first wire 481b as shown in FIGS. Further, the rear first wire 481b is constituted by two divided wires 481c and 481d. The split wire 481c is wound around the first pulley 31 and fixed. The dividing wire 481d is wound around the third pulley 33 and fixed. The split wire 481c and the split wire 481d are connected via a lower wire support member 491a, an upper wire support member 491b, and a compression spring 495, which will be described later.

The drive unit 410 includes a moving mechanism 490. The moving mechanism 490 is provided on the support member 20. The moving mechanism 490 includes a lower wire support member 491a, an upper wire support member 491b, a compression spring 495, a link mechanism 492, and a movable pulley 494.

The lower wire support member 491a and the upper wire support member 491b are plate-like members that face each other in the vertical direction. The lower wire support member 491a and the upper wire support member 491b are provided on the rear side (−X side) with respect to the support member 20.

The lower wire support member 491a is formed with a through hole 491c that penetrates the lower wire support member 491a in the vertical direction. A split wire 481c drawn from the first pulley 31 is passed through the through hole 491c from below. The upper end of the split wire 481c passed through the through hole 491c is fixed to the lower surface of the upper wire support member 491b.

The upper wire support member 491b is located above the lower wire support member 491a. The upper wire support member 491b is formed with a through hole 491d that penetrates the upper wire support member 491b in the vertical direction. The through hole 491d is formed at a position shifted from the through hole 491c of the lower wire support member 491a in plan view. A split wire 481d drawn from the third pulley 33 is passed through the through hole 491d from above. The lower end of the split wire 481d passed through the through hole 491d is fixed to the upper surface of the lower wire support member 491a.

The compression spring 495 is disposed between the lower wire support member 491a and the upper wire support member 491b in the vertical direction, and connects the lower wire support member 491a and the upper wire support member 491b. The compression spring 495 applies a force to the lower wire support member 491a and the upper wire support member 491b in a direction to separate the lower wire support member 491a and the upper wire support member 491b from each other.

The link mechanism 492 is fixed to the lower wire support member 491a and the upper wire support member 491b. The link mechanism 492 extends to the front side (+ X side) from the lower wire support member 491a and the upper wire support member 491b as a whole. The link mechanism 492 includes first links 492a and 492b and second links 493a and 493b.

The first link 492a is rotatably connected to the front (+ X side) end of the lower wire support member 491a. The first link 492a extends diagonally forward from the front (+ X side) end of the lower wire support member 491a. The first link 492b is rotatably connected to the front end of the upper wire support member 491b. The first link 492b extends obliquely forward and downward from the front end of the upper wire support member 491b. The first link 492a and the first link 492b are arranged so as to intersect with each other, and are connected to each other through a connection shaft 492c so as to be rotatable.

The second link 493a is rotatably connected to the front (+ X side) end of the first link 492a. The second link 493a extends from the front end of the first link 492a obliquely downward to the front. The second link 493b is rotatably connected to the front end of the first link 492b. The second link 493b extends diagonally forward and upward from the front end of the first link 492b. The front end portion of the second link 493a and the front end portion of the second link 493b are rotatably connected to each other.

The movable pulley 494 is connected to the front (+ X side) end of the link mechanism 492. More specifically, the movable pulley 494 is connected to a location where the second links 493a and 493b are connected to each other. A front first wire 81a is hung on the movable pulley 494. The movable pulley 494 is in contact with the front first wire 81a from the rear side (−X side).

Here, FIG. 15 shows a case where the load of the first motor 21 is relatively small and the tension of the first wire 481 is relatively small. FIG. 16 shows a case where the load of the first motor 21 is relatively large and the tension of the first wire 481 is relatively large.

When the tension of the first wire 481 becomes relatively large, as shown in FIG. 16, the lower wire support member 491a and the upper wire support member 491b are pulled by the split wire 481c and the split wire 481d and approach each other. Moving. Thereby, the inclination with respect to the front-back direction (X-axis direction) of each link of the link mechanism 492 decreases, and the dimension of the link mechanism 492 in the front-rear direction increases. Accordingly, the movable pulley 494 connected to the front end (+ X side) of the link mechanism 492 moves to the front side and pushes the front first wire 81a to the front side. As a result, the front first wire 81a moves in the direction away from the front side, that is, the second rotation center axis J2.

When the tension of the first wire 481 becomes relatively small, the lower wire support member 491a and the upper wire support member 491b move in the vertical direction away from each other by the elastic force of the compression spring 495, as shown in FIG. As a result, the dimension of the link mechanism 492 in the front-rear direction (X-axis direction) is reduced, and the movable pulley 494 moves rearward (−X side). As a result, the front first wire 81a moves to the rear side, that is, in a direction approaching the second rotation center axis J2.

As described above, the moving mechanism 490 moves the first wire 481 (front first wire 81a) to a position away from the second rotation center axis J2 as the tension of the first wire 481 increases.

According to the present embodiment, as the tension of the first wire 481 increases, the first wire 481 moves away from the second rotation center axis J2, so that the second rotation center axis applied to the support member 20 via the first wire 481. The moment arm of the rotational moment around J2 can be increased. Therefore, a load sensitive mechanism that can increase the output around the second rotation center axis J2 as the load of the first motor 21 increases is obtained.

In addition, according to the present embodiment, the link mechanism 492 that pushes out the movable pulley 494 using the tension of the first wire 481 is provided, and therefore, the movable pulley 494 is more at the second rotation center than in the third embodiment. It can be moved to a position away from the axis J2. Therefore, as the load on the first motor 21 increases, the output around the second rotation central axis J2 can be increased.

In the above description, only one moving mechanism 490 is provided and only the front first wire 81a is moved. However, the present invention is not limited to this. For example, two moving mechanisms 490 may be provided to move the rear first wire 481b to the rear side. Further, for example, when the tension of the first wire 481 increases, the lower wire support member 491a and the upper wire support member 491b may move rearward. In this case, both the front first wire 81a and the rear first wire 481b can be moved in a direction away from the second rotation center axis J2 by one moving mechanism 490.

Further, the moving mechanism 490 of the present embodiment described above may be combined with the moving mechanisms 390a and 390b of the third embodiment. In addition, each moving mechanism may be provided for the second wire 82.

In addition, the manipulator of each embodiment mentioned above may be used for any apparatus, apparatus, etc. Moreover, the number of arms connected by the drive unit and the drive unit is not particularly limited.

Further, the above-described configurations can be appropriately combined within a range that does not contradict each other.

DESCRIPTION OF SYMBOLS 1 ... Manipulator, 20 ... Support member (1st member), 21 ... 1st motor (1st drive device), 21a ... 1st output shaft (output shaft), 22 ... 2nd motor (2nd drive device), 22a ... 2nd output shaft (output shaft), 31 ... 1st pulley (1st rotation member), 32 ... 2nd pulley (2nd rotation member), 33 ... 3rd pulley (3rd rotation member), 43 ... Upper arm part (Second member), 46 ... forearm part (second member), 47 ... hand part (second member), 50 ... tension adjusting mechanism, 81, 181, 481 ... first wire (first transmission member), 82, 182 ... second wire (second transmission member), 124a, 124b ... motor clamping member (second member), 124c ... connection member (second member), 230 ... variable mechanism, 390a, 390b, 490 ... movement mechanism, J1 , J3, J5: First rotation center axis, J2, J4, J6: During second rotation Axis

Claims (6)

1. A first member;
   A second member attached to the one member so as to be rotatable around a first rotation center axis;
   A first rotating member and a second rotating member which are attached to both the first member and the second member so as to be rotatable around the first rotation center axis;
   A third rotating member attached to the first member so as to be rotatable around a second rotation center axis different from the first rotation center axis;
   A first driving device for rotating the first rotating member around the first rotation center axis;
   A second driving device for rotating the second rotating member around the first rotation center axis;
   A first transmission member that connects the first rotation member and the third rotation member and transmits the rotation of the first rotation member to the third rotation member via a tension;
   A second transmission member that connects the second rotation member and the third rotation member, and transmits the rotation of the second rotation member to the third rotation member via a tension;
   With
   The first transmission member is directed in one direction around the second rotation center axis with respect to the third rotation member when a rotation torque in one direction around the first rotation center axis is applied to the first rotation member. The rotational torque of
   The second transmission member faces the other direction around the second rotation center axis with respect to the third rotation member when a rotation torque in one direction around the first rotation center axis is applied to the second rotation member. A manipulator characterized by transmitting the rotational torque of the motor.
2. The manipulator according to claim 1, wherein the first driving device and the second driving device are fixed to the second member.
3. The output shaft of the first drive device and the output shaft of the second drive device are centered on the first rotation center axis,
   The first rotating member is fixed to the output shaft of the first driving device,
   The manipulator according to claim 2, wherein the second rotating member is fixed to an output shaft of the second driving device.
4. The manipulator according to any one of claims 1 to 3, further comprising a tension adjustment mechanism that adjusts a tension of the first transmission member.
5. The manipulator according to any one of claims 1 to 4, wherein the first rotating member includes a variable mechanism that reduces the diameter of the first rotating member as the tension of the first transmission member increases.
6. The manipulator according to any one of claims 1 to 5, further comprising a moving mechanism that moves the first transmission member to a position farther from the second rotation center axis as the tension of the first transmission member increases. .

Images