JP6482188B2 - Robot arm - Google Patents

Description

  The present invention relates to a robot arm, and more particularly to a robot arm of an industrial robot using a parallel mechanism.

  Conventionally, a robot arm of an industrial robot using a parallel mechanism is known (for example, see Patent Document 1).

  This robot arm has a base part, three arm bodies arranged at equal angles with the vertical axis C1 of the base part as the center, and a bracket. Each arm body includes a first arm and a second arm. Each first arm is attached to an arm support member that rotates about an axis C2 whose base end portion is parallel to the base portion. Each second arm includes a pair of rods. And each 2nd arm is comprised so that the axis line C3 which passes along the base end part of a pair of rod, and is parallel to the axis line C4, and the axis line C4 which passes along the front-end | tip part of a pair of rod maintain a parallel relationship. Yes. The bracket swings around the free end of each second arm. Accordingly, when each first arm is moved around the axis C2, the bracket is moved while maintaining a parallel relationship with the base portion.

JP 2009-248286 A

  However, the robot arm described in Patent Document 1 has a problem in that each arm main body greatly protrudes from the base portion to the outside in the radial direction of the vertical axis C1 to increase the installation area.

  In order to solve the above problems, a robot arm according to an aspect of the present invention includes a fixed plate extending in parallel to a first plane including first to third arm rotation axes intersecting at a first center point, and a base plate. A first arm whose end is connected to the fixed plate so as to be rotatable about the first arm rotation axis, and a base end which is connected to the fixed plate so as to be rotatable about the second arm rotation axis A second arm that is connected; and a third arm that has a base end portion that is connected to the fixed plate so as to be rotatable about the third arm rotation axis. A first subunit configured to move on the first phantom spherical surface centered on the first center point by rotating the arms, and a second subunit; Fourth to sixth arm rotation shafts intersecting at the center point An intermediate plate extending parallel to the second plane including the intermediate portion between the base end portion and the distal end portion is coupled to the intermediate plate so as to be rotatable about the fourth arm rotation axis. A fourth arm, a fifth arm in which an intermediate portion between the base end portion and the tip end portion is connected to the intermediate plate so as to be rotatable around the fifth arm rotation axis, a base end portion and a tip end portion; An intermediate portion between the intermediate plate and a sixth arm connected to the intermediate plate so as to be rotatable about the sixth arm rotation axis, and the fourth to sixth arms are rotated. A second subunit configured such that the distal end portion and the proximal end portion of the fourth to sixth arms move on a second phantom spherical surface centered on the second center point; and a third center point An output profile extending parallel to the third plane including the intersecting seventh to ninth arm rotation axes. , A seventh arm whose base end is connected to the output plate so as to be rotatable about the seventh arm rotation axis, and a base end is rotatable about the eighth arm rotation axis And an eighth arm connected to the output plate, and a ninth arm having a base end portion connected to the output plate so as to be rotatable about the ninth arm rotation axis. A third sub is configured such that the tip ends of the seventh to ninth arms move on a third phantom spherical surface centered on the third center point by rotating the seventh to ninth arms. A distal end portion of each of the first to third arms of the first subunit is R-B-R to a proximal end portion of the fourth to sixth arms of the second subunit, respectively. Connected by a rotary joint of the mold, the second subunit of the second subunit The distal ends of the fourth to sixth arms are connected to the distal ends of the seventh to ninth arms of the third subunit by R-B-R type rotary joints, respectively.

  According to this configuration, the output plate can be moved relative to the fixed plate by rotating the first arm, the second arm, and the third arm.

  The first subunit, the second subunit, and the third subunit are arranged in a row in the direction in which the robot arm extends, and the first to ninth arms are stretched in a direction perpendicular to the extending direction of the robot arm. Therefore, the robot arm can be reduced in size.

  The fixed plate and the intermediate plate are configured to be symmetrically located with respect to a predetermined first symmetry plane, and the intermediate plate and the output plate are predetermined to extend in parallel with the first symmetry plane. It may be configured to be positioned symmetrically with respect to the second symmetry plane.

  According to this configuration, the output plate can be moved so that the output plate and the fixed plate extend in parallel.

  An R-B-R type rotary joint connecting the distal end portions of the first to third arms of the first subunit and the proximal end portions of the fourth to sixth arms of the second subunit. Each includes a fixed-side connecting piece and an intermediate-side first connecting piece connected to the fixed-side connecting piece so as to be rotatable around a bending axis, and the fixed-side connecting piece has the first center point. The intermediate first connecting piece passes through the second center point and passes through the bending axis, and is connected to the distal ends of the first to third arms so as to be rotatable around an axis orthogonal to the bending axis. Connected to the base ends of the fourth to sixth arms so as to be rotatable around an axis orthogonal to the front end of the fourth subunits of the second subunit and the third subunits. An R-B-R type rotating shaft connecting the tip ends of the seventh to ninth arms. Each of the inlets includes an intermediate second connecting piece and an output connecting piece connected to the intermediate second connecting piece so as to be rotatable around a bending axis, and the intermediate second connecting piece includes: The output side connecting piece passes through the third center point and passes through the second center point and is connected to the tip end portions of the fourth to sixth arms so as to be rotatable around an axis orthogonal to the bending axis. You may connect with the front-end | tip part of the said 7th thru | or 9th arm so that rotation around the axis line orthogonal to the said bending axis line is possible.

  According to this configuration, the first to third subunits can be connected even when the relative positions of the first to third subunits change.

  A first drive unit that drives the first arm to rotate about the first arm rotation axis; a second drive unit that drives the second arm to rotate about the second arm rotation axis; and the third arm And a third drive unit that rotates the third arm around the rotation axis of the third arm.

  According to this configuration, the output plate can be positioned at a predetermined position by driving the first to third driving units.

  An odd number of the second subunits are provided, and the odd number of second subunits are arranged in a row of second subunits adjacent to the tip ends of the fourth to sixth arms of one second subunit. The base ends of the fourth to sixth arms and the R-B-R type rotary joints are connected to each other, and the distal ends of the first to third arms of the first subunit are connected to each other. Are connected to the base ends of the fourth to sixth arms of the second subunit located at one end of the second subunit by the R-B-R type rotary joint, and are connected to each other. The distal ends of the fourth to sixth arms of the second subunit located at the other end of the second subunit are the distal ends of the seventh to ninth arms of the third subunit, respectively. And R-B-R type times It may be connected by a joint.

  According to this configuration, the distance between the first subunit and the third subunit is set to be radially outside the center line passing through the first center point of the first subunit and the third center point of the third subunit. It can extend, suppressing the overhang dimension of the 1st-9th arm.

  You may further provide the turning mechanism which rotates the said fixed plate around a turning axis.

  According to this configuration, the hand connected to the output plate can be rotated around the previous axis with a simple configuration.

  The present invention has an effect that the robot arm can be reduced in size.

It is a figure which shows the structural example of the robot arm which concerns on Embodiment 1 of this invention. It is a figure which shows schematically the structural example of the robot arm of FIG. FIG. 2 is a diagram schematically illustrating a configuration example of a first subunit of the robot arm of FIG. 1. It is a figure which shows schematically the structural example of the 2nd subunit of the robot arm of FIG. It is a figure which shows roughly the structural example of the 3rd subunit of the robot arm of FIG. It is a figure which shows schematically the structural example of the robot arm of FIG. 1, and is a figure which shows the structure by which the 1st arm, the 4th arm, and the 7th arm are connected by the RBR type rotary joint. . It is a figure which shows schematically the structural example of the robot arm of FIG. 1, and is a figure which shows the structure by which the 2nd arm, the 5th arm, and the 8th arm are connected by the RBR type rotary joint. . It is a figure which shows schematically the structural example of the robot arm of FIG. 1, and is a figure which shows the structure by which the 3rd arm, the 6th arm, and the 9th arm are connected by the RBR type rotary joint. . It is a figure which shows schematically the operation example of the robot arm of FIG. It is a perspective view which shows the structural example of the robot arm which concerns on Embodiment 2 of this invention, and is a figure which shows a 1st state. It is a perspective view which shows the structural example of the robot arm of FIG. 6, and is a figure which shows a 2nd state. FIG. 7 is a diagram schematically illustrating a configuration example of a robot arm in FIG. 6. It is a figure which shows the structural example of the robot arm which concerns on Embodiment 4 of this invention, and is a figure which shows a 1st state. It is a figure which shows the structural example of the robot arm of FIG. 8, and is a figure which shows a 2nd state. It is a figure which shows the structural example of the robot arm which concerns on Embodiment 5 of this invention, and is a figure which shows a 1st state. It is a figure which shows the structural example of the robot arm of FIG. 11A, and is a figure which shows a 2nd state. It is a figure which shows the structural example of the robot arm of FIG. 11A, and is a figure which shows a 3rd state. It is a figure which shows the structural example of the robot arm which concerns on Embodiment 6 of this invention, and is a figure which shows a 1st state. It is a figure which shows the structural example of the robot arm of FIG. 12A, and is a figure which shows a 2nd state. It is a figure which shows the structural example of the robot arm of FIG. 12A, and is a figure which shows a 3rd state. It is a figure which shows the structural example of the robot arm which concerns on Embodiment 7 of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout the drawings, and redundant description thereof is omitted.

(Embodiment 1)
FIG. 1 is a diagram showing a configuration example of a robot arm 100 according to the first embodiment of the present invention.

  As shown in FIG. 1, the robot arm 100 is a parallel mechanism in which the fixed plate 10 and the output plate 30 are connected in parallel by a plurality of links, and the output plate can be positioned at an arbitrary position in the operation region. It is configured as follows.

  FIG. 2 is a diagram schematically illustrating a configuration example of the robot arm 100.

[overall structure]
As shown in FIG. 2, the robot arm 100 includes a first subunit 1, a second subunit 2, a third subunit 3, a first subunit 1, and a second subunit 2 that are connected to each other. A connection mechanism 4, a second connection mechanism 5 that connects the second subunit 2 and the third subunit 3, and an arm drive mechanism 6 are provided.

  In the present embodiment, the robot arm 100 is provided so as to extend upward from the first subunit 1 toward the third subunit 3, but is not limited thereto, and extends downward. Or may be provided so as to extend laterally.

[First subunit]
FIG. 3A is a diagram schematically illustrating a configuration example of the first subunit 1 of the robot arm 100.

  As shown in FIG. 3A, the first subunit 1 has a fixed plate 10, a first arm 11, a second arm 12, and a third arm 13.

  The fixed plate 10 extends in parallel to a first plane F1 including a first arm rotation axis L1, a second arm rotation axis L2, and a third arm rotation axis L3 that intersect at the first center point O1. The fixed plate 10 is fixed to a base (not shown), for example. The fixed plate 10 can have an arbitrary shape such as a plate-like body or a columnar body.

  The first arm 11, the second arm 12, and the third arm 13 are formed in the same shape as each other, for example, are formed so as to extend in an arc shape along the first phantom spherical surface S1 centered on the first center point O1. Has been. Thereby, the extension of the first arm 11, the second arm 12, and the third arm 13 in the extending direction of the first plane F1 (or the direction orthogonal to the extending direction of the robot arm 100) can be suppressed. The first arm 11, the second arm 12, and the third arm 13 each have an arc angle from the base end to the tip, that is, a first imaginary line connecting the first center point O1 and the tip of the arm. An angle formed by an imaginary line connecting the center point O1 and the base end portion of the arm connected to the fixed plate 10 is, for example, 90 degrees.

  The first arm 11 has a base end portion 11a connected to the fixed plate 10 and a first arm rotation axis L1 between a lying position and a standing position where the tip portion is located above the lying position. It is connected so that it can rotate. The second arm 12 has a base end portion 12a connected to the fixed plate 10, and rotates around the second arm rotation axis L2 between a lying position and a standing position where the tip portion is located above the lying position. Connected as possible. The third arm 13 is connected to the fixed plate 10 at the base end portion 13a, and rotates around the third arm rotation axis L3 between a lying position and a standing position where the tip portion is located above the lying position. Connected as possible.

  The first arm 11, the second arm 12, and the third arm 13 are, for example, such that the first arm rotation axis L1, the second arm rotation axis L2, and the third arm rotation axis L3 are on the first plane F1. , The first center point O1 is connected to the fixed plate 10 so as to be rotationally symmetrical at equal intervals of 120 degrees.

  Accordingly, the first arm 11, the second arm 12, and the third arm 13 are rotated so that the distal end portion 11 b of the first arm 11, the distal end portion 12 b of the second arm 12, and the distal end portion 13 b of the third arm 13. Are configured to move along trajectories T1, T2, and T3 on the first phantom spherical surface S1, respectively. The first plane F1 described above constitutes the equator plane of the first phantom spherical surface S1.

[Second subunit]
FIG. 3B is a diagram schematically illustrating a configuration example of the second subunit 2 of the robot arm 100.

  As illustrated in FIG. 3B, the second subunit 2 includes an intermediate plate 20, a fourth arm 21, a fifth arm 22, and a sixth arm 23.

  The intermediate plate 20 extends in parallel to the second plane F2 including the fourth arm rotation axis L4, the fifth arm rotation axis L5, and the sixth arm rotation axis L6 that intersect at the second center point O2. The shape of the intermediate plate 20 is preferably a plate-like body to avoid interference with the arm, but is not limited thereto.

  The fourth arm 21, the fifth arm 22, and the sixth arm 23 are formed in the same shape. The portion from the middle part to the base end part of the fourth arm 21, the fifth arm 22, and the sixth arm 23 is, for example, more than the second plane F2 of the second phantom spherical surface S2 centered on the second center point O2. It is formed to extend in an arc shape along the spherical surface of the portion on the first subunit 1 side. Further, the portion from the middle portion to the tip portion of the fourth arm 21, the fifth arm 22, and the sixth arm 23 is, for example, from the second plane F2 of the second phantom spherical surface S2 centered on the second center point O2. Is also formed to extend in an arc along the spherical surface of the portion on the third subunit 3 side. Thereby, the extension of the fourth arm 21, the fifth arm 22, and the sixth arm 23 in the extending direction of the second plane F2 (or the direction orthogonal to the extending direction of the robot arm 100) can be suppressed.

  And the 4th arm 21 is connected with the intermediate part 20c between the base end part 21a and the front-end | tip part 21b with the intermediate | middle plate 20, and is connected so that rotation around the 4th arm rotation axis L4 is possible. The fifth arm 22 has an intermediate portion 22c between the base end portion 22a and the distal end portion 22b connected to the intermediate plate 20, and is connected to be rotatable about the fifth arm rotation axis L5. In the sixth arm 23, an intermediate portion 23c between the base end portion 23a and the distal end portion 23b is connected to the intermediate plate 20, and is connected so as to be rotatable around the sixth arm rotation axis L6.

  The fourth arm 21, the fifth arm 22, and the sixth arm 23 are, for example, the fourth arm rotation axis L4, the fifth arm rotation axis L5, and the sixth arm rotation axis L6 are the second plane. On F2, it is connected to the intermediate plate 20 so as to be positioned rotationally symmetrical at equal intervals of 120 degrees around the second center point O2.

  Therefore, when the fourth arm 21, the fifth arm 22, and the sixth arm 23 rotate, the base end portion 21 a of the fourth arm 21, the base end portion 22 a of the fifth arm 22, and the sixth arm 23 The base end portion 23a is configured to move on the spherical surface on the first subunit 1 side with respect to the second plane F2 of the second phantom spherical surface S2. At the same time, the distal end portion 21b of the fourth arm 21, the distal end portion 22b of the fifth arm 22, and the distal end portion 23b of the sixth arm 23 are closer to the third subunit 3 than the second plane F2 of the second phantom spherical surface S2. It is configured to move on a spherical surface. The second plane F2 described above constitutes the equator plane of the second phantom spherical surface S2. In the fourth arm 21, the fifth arm 22, and the sixth arm 23, a second virtual circle C2 (details will be described later) passing through the base end portions of these arms passes through the distal end portions of these arms. It is configured to extend in parallel with a virtual circle C4 (details will be described later).

  In the present embodiment, the distal ends of the fourth arm 21, the fifth arm 22, and the sixth arm 23 are moved relative to the second center point O2 of the second subunit 2 by the rotation of these arms. It is configured to move the point symmetry position. However, it is not limited to this configuration. Further, the second phantom spherical surface S2 on the first subunit 1 side from the second plane F2 in which the base ends of the fourth arm 21, the fifth arm 22, and the sixth arm 23 move, the fourth arm 21, The second phantom spherical surface S <b> 2 on the third subunit 3 side may be configured to have a different diameter from the second plane F <b> 2 on which the distal ends of the fifth arm 22 and the sixth arm 23 move.

  The fourth arm 21, the fifth arm 22, and the sixth arm 23 are configured such that the second phantom spherical surface S2 has the same diameter as the first phantom spherical surface S1 of the first subunit 1. Further, a portion of the second subunit 2 closer to the first subunit 1 than the second plane F2 of the second phantom spherical surface S2 and the first phantom spherical surface S1 of the first subunit 1 are a first symmetry plane to be described later. It is comprised so that it may be located symmetrically on the basis of.

[Third subunit]
FIG. 3C is a diagram schematically illustrating a configuration example of the third subunit 3 of the robot arm 100.

  As shown in FIG. 3C, the third subunit 3 includes an output plate 30, a seventh arm 31, an eighth arm 32, and a ninth arm 33.

  The output plate 30 extends in parallel with a third plane F3 including a seventh arm rotation axis L7, an eighth arm rotation axis L8, and a ninth arm rotation axis L9 that intersect at the third center point O3. The shape of the output plate 30 is preferably a plate-like body to avoid interference with the arm, but is not limited to this. A hand (not shown) is attached to the output plate 30. In addition, the cable (not shown) connected to this hand is attached along the 1st arm 11, the 4th arm 21, and the 7th arm 31, for example.

  The seventh arm 31, the eighth arm 32, and the ninth arm 33 are formed in the same shape as each other, for example, are formed so as to extend in an arc shape along the third phantom spherical surface S3 with the third center point O3 as the center. Has been. Thus, the extension of the seventh arm 31, the eighth arm 32, and the ninth arm 33 in the extending direction of the third plane F3 (or the direction orthogonal to the extending direction of the robot arm 100) can be suppressed. The third arm 31, the eighth arm 32, and the ninth arm 33 each have a circular arc angle from the base end to the tip, that is, a virtual line connecting the third center point O3 and the tip of the arm and the third arm. An angle formed by an imaginary line connecting the center point O3 and the base end portion of the arm connected to the output plate 30 is, for example, 90 degrees.

  The seventh arm 31 is connected to the output plate 30 at the base end portion 31a so as to be rotatable around the seventh arm rotation axis L7. The eighth arm 32 has a base end portion 32a connected to the output plate 30, and is connected to be rotatable about the second arm rotation axis L2. The base end 33a of the ninth arm 33 is connected to the output plate 30, and is connected to be rotatable about the third arm rotation axis L3.

  The seventh arm 31, the eighth arm 32, and the ninth arm 33 are, for example, the seventh arm rotation axis L7, the eighth arm rotation axis L8, and the ninth arm rotation axis L9 on the third plane F3. Are connected to the output plate 30 so as to be positioned rotationally symmetrical at equal intervals of 120 degrees around the third center point O3.

  Therefore, when the seventh arm 31, the eighth arm 32, and the ninth arm 33 are rotated, the distal end portion 31b of the seventh arm 31, the distal end portion 32b of the eighth arm 32, and the distal end portion 33b of the ninth arm 33 are displayed. Are configured to move on the third phantom spherical surface S3. The third plane F3 described above constitutes the equator plane of the third phantom spherical surface S3.

  In the seventh arm 31, the eighth arm 32, and the ninth arm 33, the first phantom spherical surface S1 and the second subunit of the first subunit 1 are the third phantom spherical surface S3 on which the tips of these arms move. It is comprised so that it may have the same diameter as 2nd 2nd virtual spherical surface S2. Further, a portion of the second subunit 2 closer to the third subunit 3 than the second plane F2 of the second phantom spherical surface S2 and the third phantom spherical surface S3 of the third subunit 3 are a second symmetry plane to be described later. It is comprised so that it may be located symmetrically on the basis of.

[First coupling mechanism]
FIG. 4A is a diagram schematically illustrating a configuration example of the robot arm 100, in which the first arm 11, the fourth arm 21, and the seventh arm 31 are connected by an RBR type rotary joint. FIG. FIG. 4B is a diagram schematically illustrating a configuration example of the robot arm 100, in which the second arm 12, the fifth arm 22, and the eighth arm 32 are connected by an RBR type rotary joint. FIG. FIG. 4C is a diagram schematically illustrating a configuration example of the robot arm 100, in which the third arm 13, the sixth arm 23, and the ninth arm 33 are connected by an RBR type rotary joint. FIG.

  As shown in FIG. 2, the first connecting mechanism 4 includes a first connecting portion 41 that connects the first arm 11 of the first subunit 1 and the fourth arm 21 of the second subunit 2, and the first subunit. A second connecting portion 42 for connecting the first second arm 12 and the fifth arm 22 of the second subunit 2, the third arm 13 of the first subunit 1, and the sixth arm 23 of the second subunit 2. And a third connecting portion 43 for connecting the two.

  The first connecting portion 41, the second connecting portion 42, and the third connecting portion 43 are all R-B-R type rotary joints and are formed in the same shape.

  That is, as shown to FIG. 4A, the 1st connection part 41 has the fixed side connection piece 41a and the intermediate | middle side connection piece 41b (intermediate side 1st connection piece). The fixed-side connecting piece 41a is connected to the tip end portion 11b of the first arm 11 so as to be rotatable around an axis Lr1 passing through the first center point O1 and the tip end portion 11b of the first arm 11. The intermediate side connecting piece 41b is connected to the base end portion 21a of the fourth arm 21 so as to be rotatable around an axis Lr4 passing through the second center point O2 and the base end portion 21a of the fourth arm 21. The fixed side connecting piece 41a and the intermediate side connecting piece 41b are connected to each other so as to be rotatable around the first bending axis Lb1. The first bending axis Lb1 intersects the axis Lr1 and the axis Lr4 perpendicular to the plane including the axis Lr1 and the axis Lr4 at the intersection of the axis Lr1 and the axis Lr4.

  As shown in FIG. 4B, the second connecting portion 42 includes a fixed side connecting piece 42a and an intermediate side connecting piece 42b (intermediate side first connecting piece). The fixed-side coupling piece 42a is coupled to the distal end portion 12b of the second arm 12 so as to be rotatable around an axis Lr2 passing through the first center point O1 and the distal end portion 12b of the second arm 12. The intermediate side connecting piece 42b is connected to the base end portion 22a of the fifth arm 22 so as to be rotatable around an axis Lr5 passing through the second center point O2 and the base end portion 22a of the fifth arm 22. The fixed side connecting piece 42a and the intermediate side connecting piece 42b are connected to each other so as to be rotatable around the second bending axis Lb2. The second bending axis Lb2 intersects the axis Lr2 and the axis Lr5 perpendicular to the plane including the axis Lr2 and the axis Lr5 at the intersection of the axis Lr2 and the axis Lr5.

  As shown in FIG. 4C, the third connecting portion 43 includes a fixed side connecting piece 43a and an intermediate side connecting piece 43b (intermediate side first connecting piece). The fixed-side coupling piece 43a is coupled to the distal end portion 13b of the third arm 13 so as to be rotatable around an axis Lr3 passing through the first central point O1 and the distal end portion 13b of the third arm 13. The intermediate side connecting piece 43b is connected to the base end portion 23a of the sixth arm 23 so as to be rotatable about an axis Lr6 passing through the second center point O2 and the base end portion 23a of the sixth arm 23. The fixed side connecting piece 43a and the intermediate side connecting piece 43b are connected to each other so as to be rotatable about the third bending axis Lb3. The third bending axis Lb3 intersects the axis Lr3 and the axis Lr6 perpendicular to the plane including the axis Lr3 and the axis Lr6 at the intersection of the axis Lr3 and the axis Lr6.

  Therefore, the first connecting portion 41, the second connecting portion 42, and the third connecting portion 43 are arranged so that the distal end portions 11 b of these arms are rotated when the first arm 11, the second arm 12, and the third arm 13 are rotated. , 12b, 13b, the first virtual circle C1 on the first virtual spherical surface S1, and the second virtual circle passing through the base ends 21a, 22a, 23a of the fourth arm 21, the fifth arm 22, and the sixth arm 23. It is comprised so that C2 and the state extended in parallel may be maintained.

  As described above, the portion of the second subunit 2 on the first subunit 1 side relative to the second plane F2 of the second phantom spherical surface S2 and the first phantom spherical surface S1 of the first subunit 1 are the first It is configured to be positioned symmetrically with respect to the symmetry plane. Further, the intermediate plate 20 of the second subunit 2 and the fixed plate 10 of the first subunit 1 are configured to be positioned symmetrically with respect to the first symmetry plane. In the present embodiment, the first symmetry plane is a plane on which the third imaginary circle C3 in which the first bending axis Lb1, the second bending axis Lb2, and the third bending axis Lb3 are tangents extends. The first symmetry plane (the third virtual circle C3) is configured to extend in parallel with the first virtual circle C1 and the second virtual circle C2 between the first virtual circle C1 and the first virtual circle C2. Has been. The position of the first symmetry plane is not limited to the above position.

  And if the 1st arm 11, the 2nd arm 12, and the 3rd arm 13 rotate and the diameter of the 1st virtual circle C1 shrinks, the 1st connection part 41, the 2nd connection part 42, and the 3rd connection part 43 moves the base end portions 21a, 22a, and 23a of the fourth arm 21, the fifth arm 22, and the sixth arm 23 so as to approach each other and reduce the diameter of the second virtual circle C2. In addition, when the first arm 11, the second arm 12, and the third arm 13 rotate and the diameter of the first virtual circle C1 increases, the first connecting portion 41, the second connecting portion 42, and the third connecting portion. 43 moves the base ends 21a, 22a, and 23a of the fourth arm 21, the fifth arm 22, and the sixth arm 23 so as to increase the diameter of the second virtual circle C2 while being spaced apart from each other. At this time, the angle between the axis Lr1 and the axis Lr4, the angle between the axis Lr2 and the axis Lr5, and the angle between the axis Lr3 and the axis Lr6 change, but the output side connecting piece of the corresponding connecting portion is connected to the intermediate side It rotates around the bending axis with respect to the piece to absorb the change in angle.

  Further, when the first arm 11, the second arm 12, and the third arm 13 rotate and the posture of the first virtual circle C1 with respect to the first plane F1 changes, that is, the first plane F1 and the first virtual circle C1. When the angle formed by the axis of the first connecting portion 41, the second connecting portion 42, and the third connecting portion 43 changes so that the second virtual circle C2 extends in parallel with the first virtual circle C1. Next, the base end portions 21a, 22a and 23a of the fourth arm 21, the fifth arm 22 and the sixth arm 23 are moved. At this time, the relative angular position around the axis Lr1 between the first arm 11 and the first connecting portion 41 and the relative angular position around the axis Lr4 between the fourth arm 21 and the first connecting portion 41 change. However, the 1st connection part 41 rotates relatively around the axis line Lr1 and the axis line Lr4 with respect to the 1st arm 11 and the 4th arm 21, respectively, and absorbs the change of the said angular position. In addition, the relative angular position around the axis Lr2 between the second arm 12 and the second connecting portion 42 and the relative angular position around the axis Lr5 between the fifth arm 22 and the second connecting portion 42 change. The second connecting portion 42 rotates relative to the second arm 12 and the fifth arm 22 around the axis Lr2 and the axis Lr5, respectively, and absorbs the change in the angular position. Furthermore, the relative angular position around the axis Lr3 between the third arm 13 and the third connecting portion 43 and the relative angular position around the axis Lr6 between the sixth arm 23 and the third connecting portion 43 change. The third connecting portion 43 rotates relative to the third arm 13 and the sixth arm 23 around the axis Lr3 and the axis Lr6, respectively, and absorbs the change in the angular position.

  Accordingly, when the distal ends of the first arm 11, the second arm 12, and the third arm 13 of the first subunit 1 move on the first phantom spherical surface S <b> 1, the first coupling mechanism 4 is connected to the second subunit 2. The fourth arm 21, the second imaginary circle C2 defined by the base end portion of each arm extends in parallel with the first imaginary circle C1 defined by the distal end portion of each arm of the first subunit 1. The base end portions of the fifth arm 22 and the sixth arm 23 are moved, and as a result, the intermediate plate 20 is positioned symmetrically with the fixed plate 10 with respect to the extending surface (first symmetry plane) of the third virtual circle C3. To move.

[Second coupling mechanism]
The second connection mechanism 5 is formed in the same shape as the first connection mechanism 4. As shown in FIG. 2, the second connecting mechanism 5 includes a fourth connecting portion 44 that connects the fourth arm 21 of the second subunit 2 and the seventh arm 31 of the third subunit 3, and a second subunit. A fifth connecting portion 45 that connects the second fifth arm 22 and the eighth arm 32 of the third subunit 3, a sixth arm 23 of the second subunit 2, and a ninth arm 33 of the third subunit 3. And a sixth connecting portion 46 for connecting the two.

  The fourth connecting portion 44, the fifth connecting portion 45, and the sixth connecting portion 46 are all R-B-R type rotary joints and are formed in the same shape.

  That is, as shown to FIG. 4A, the 4th connection part 44 has the intermediate side connection piece 44a (intermediate side 2nd connection piece) and the output side connection piece 44b. The intermediate coupling piece 44a is coupled to the distal end portion 21b of the fourth arm 21 so as to be rotatable around an axis Lr7 passing through the second center point O2 and the distal end portion 21b of the fourth arm 21. The axis Lr7 is coaxial with the axis Lr4 of the first coupling mechanism 4, but is not limited to this. The output side connecting piece 44b is connected to the tip end portion 31b of the seventh arm 31 so as to be rotatable around an axis Lr10 passing through the third center point O3 and the tip end portion 31b of the seventh arm 31. And the intermediate | middle side connection piece 44a and the output side connection piece 44b are mutually connected so that rotation around the 4th bending axis line Lb4 is possible. The fourth bending axis Lb4 intersects the axis Lr7 and the axis Lr10 perpendicular to the plane including the axis Lr7 and the axis Lr10 at the intersection of the axis Lr7 and the axis Lr10.

  As shown in FIG. 4B, the fifth connecting portion 45 includes an intermediate side connecting piece 45a (intermediate side second connecting piece) and an output side connecting piece 45b. The intermediate side connecting piece 45a is connected to the tip end portion 22b of the fifth arm 22 so as to be rotatable around an axis Lr8 passing through the second center point O2 and the tip end portion 22b of the fifth arm 22. The axis Lr8 is coaxial with the axis Lr5 of the first coupling mechanism 4, but is not limited to this. The output side connecting piece 45b is connected to the tip end portion 32b of the eighth arm 32 so as to be rotatable around an axis Lr11 passing through the third center point O3 and the tip end portion 22b of the eighth arm 32. And the intermediate | middle side connection piece 45a and the output side connection piece 45b are mutually connected so that rotation around the 5th bending axis line Lb5 is possible. The fifth bending axis Lb5 intersects the axis Lr8 and the axis Lr11 perpendicular to the plane including the axis Lr8 and the axis Lr11 at the intersection of the axis Lr8 and the axis Lr11.

  As shown in FIG. 4C, the sixth connecting portion 46 includes an intermediate side connecting piece 46a (intermediate side second connecting piece) and an output side connecting piece 46b. The intermediate coupling piece 46a is coupled to the distal end portion 23b of the sixth arm 23 so as to be rotatable about an axis Lr9 passing through the second center point O2 and the distal end portion 23b of the sixth arm 23. The axis Lr9 is coaxial with the axis Lr6 of the first coupling mechanism 4, but is not limited to this. The output side connecting piece 46b is connected to the tip end portion 33b of the ninth arm 33 so as to be rotatable about an axis Lr12 passing through the third center point O3 and the tip end portion 33b of the ninth arm 33. And the intermediate | middle side connection piece 46a and the output side connection piece 46b are mutually connected so that rotation around the 6th bending axis Lb6 was possible. The sixth bending axis Lb6 intersects the axis Lr9 and the axis Lr12 perpendicular to the plane including the axis Lr9 and the axis Lr12 at the intersection of the axis Lr9 and the axis Lr12.

  And the 4th connection part 44, the 5th connection part 45, and the 6th connection part 46 are the front-end | tip parts 21b of these arms at the time of rotation of the 4th arm 21, the 5th arm 22, and the 6th arm 23. , 22b, 23b, the fourth imaginary circle C4 on the second phantom spherical surface S2, and the fifth imaginary circle C5 passing through the tip portions 31b, 32b, 33b of the seventh arm 31, the eighth arm 32, and the ninth arm 33. Are maintained so as to extend in parallel.

  As described above, the portion of the second subunit 2 closer to the third subunit 3 than the second plane F2 of the second phantom spherical surface S2 and the third phantom spherical surface S3 of the third subunit 3 are the second It is configured to be positioned symmetrically with respect to the symmetry plane. Further, the intermediate plate 20 of the second subunit 2 and the output plate 30 of the third subunit 3 are configured to be positioned symmetrically with respect to the second symmetry plane. In the present embodiment, the second symmetry plane is a plane on which the sixth imaginary circle C6 in which the fourth bending axis Lb4, the fifth bending axis Lb5, and the sixth bending axis Lb6 are tangent extends. The second symmetry plane (sixth virtual circle C6) is configured to extend in parallel with the fourth virtual circle C4 and the fifth virtual circle C5 between the fourth virtual circle C4 and the fifth virtual circle C5. Has been. The second symmetry plane is configured to extend in parallel with the first target plane. Note that the position of the second symmetry plane is not limited to the above position.

  And when the 4th arm 21, the 5th arm 22, and the 6th arm 23 rotate and the diameter of the 4th virtual circle C4 shrinks, the 4th connection part 44, the 5th connection part 45, and the 6th connection part 46 moves the tip portions 31b, 32b, and 33b of the seventh arm 31, the eighth arm 32, and the ninth arm 33 so as to approach each other and reduce the diameter of the fourth virtual circle C4. Further, when the fourth arm 21, the fifth arm 22, and the sixth arm 23 rotate and the diameter of the fourth virtual circle C4 increases, the fourth connecting portion 44, the fifth connecting portion 45, and the sixth connecting portion. 46 moves the distal end portions 31b, 32b, 33b of the seventh arm 31, the eighth arm 32, and the ninth arm 33 so as to increase the diameter of the fourth virtual circle C4 apart from each other. At this time, the angle between the axis Lr7 and the axis Lr10, the angle between the axis Lr8 and the axis Lr11, and the angle between the axis Lr9 and the axis Lr12 change, but the output side connecting piece of the corresponding connecting portion changes. It rotates around the bending axis with respect to the intermediate connecting piece to absorb the change in angle.

  Moreover, when the 4th arm 21, the 5th arm 22, and the 6th arm 23 rotate and the attitude | position of the 4th virtual circle C4 with respect to the 2nd plane F2 changes, ie, 2nd plane F1 and the 4th virtual circle C4. When the angle formed by the axis changes, the fourth linking part 44, the fifth linking part 45, and the sixth linking part 46 are arranged such that the fifth imaginary circle C5 extends in parallel with the fourth imaginary circle C4. The tip portions 31b, 32b, and 33b of the seventh arm 31, the eighth arm 32, and the ninth arm 33 are moved. At this time, the relative angular position around the axis Lr7 between the fourth arm 21 and the fourth connecting part 44 and the relative angular position around the axis Lr10 between the seventh arm 31 and the fourth connecting part 44 change. However, the 4th connection part 44 rotates relatively around the axis line Lr7 and the axis line Lr10 with respect to the 4th arm 21 and the 7th arm 31, respectively, and absorbs the change of the said angular position. Further, the relative angular position around the axis Lr8 between the fifth arm 22 and the fifth connecting portion 45 and the relative angular position around the axis Lr11 between the eighth arm 32 and the fifth connecting portion 45 change. The fifth connecting portion 45 rotates relative to the fifth arm 22 and the eighth arm 32 about the axis Lr8 and the axis Lr11, respectively, and absorbs the change in the angular position. Furthermore, the relative angular position around the axis Lr9 between the sixth arm 23 and the sixth connecting portion 46 and the relative angular position around the axis Lr12 between the ninth arm 33 and the sixth connecting portion 46 change. The sixth connecting portion 46 rotates relative to the sixth arm 23 and the ninth arm 33 around the axis Lr9 and the axis Lr12, respectively, and absorbs the change in the angular position.

  Therefore, when the tip ends of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 2 move on the second phantom spherical surface S <b> 2, the second coupling mechanism 5 is connected to the third subunit 3. The seventh arm 31 and the eighth arm so that the fifth virtual circle C5 defined by the tip of each arm extends in parallel with the fourth virtual circle C4 defined by the tip of each arm of the second subunit 2. The distal ends of the arm 32 and the ninth arm 33 are moved so that the output plate 30 is positioned symmetrically with the fixed plate 10 with respect to the extending surface (second symmetry plane) of the sixth virtual circle C6. Moving.

[Arm drive mechanism]
As shown in FIGS. 1 and 2, the arm drive mechanism 6 includes a first drive unit 61, a second drive unit 62, and a third drive unit 63. The 1st drive part 61, the 2nd drive part 62, and the 3rd drive part 63 are servomotors, for example. The first drive unit 61 has an output shaft connected to the first arm 11 and rotates the first arm 11 about the first arm rotation axis L1. The second drive unit 62 has an output shaft coupled to the second arm 12 and rotationally drives the second arm 12 about the second arm rotation axis L2. The third drive unit 63 has an output shaft connected to the third arm 13 and rotates the third arm 13 around the third arm rotation axis L3.

  Then, the control unit of the robot controls the angular positions of the output shafts of the first driving unit 61, the second driving unit 62, and the third driving unit 63, so that the first arm 11, the second arm 12, and the second driving unit 63 are controlled. The angular position of the three arms 13 is controlled.

[Configuration of arms connected to each other]
In the present embodiment, as shown in FIG. 1, the arm of the second subunit 2 extends so as to be folded with respect to the arm of the first subunit 1, and the arm of the third subunit 3 is Two sub-units 2 extend so as to be folded back. That is, as viewed from above, the first arm 11, the second arm 12, and the third arm 13 extend to one side in the circumferential direction centered on the first center point O1, and the fourth arm 21, the fifth arm The arm 22 and the sixth arm 23 extend to the other side in the same circumferential direction, and the seventh arm 31, the eighth arm 32, and the ninth arm 33 extend to one side in the same circumferential direction. Exist. As a result, the cable connected to the hand is wired so as to be folded before the first connecting mechanism 4 and the second connecting mechanism 5, so that the cable does not straddle the first connecting mechanism 4 and the second connecting mechanism 5. Thus, the cable connected to the hand can be easily routed.

[Operation example]
Next, an operation example of the robot arm 100 will be described.

  FIG. 5 is a diagram illustrating an operation example of the robot arm 100.

  2 and 5, first, the control unit of the robot drives the arm driving mechanism 6, and the angular position of the first arm 11 around the first arm rotation axis L <b> 1, the second arm of the second arm 12. By controlling the angular position around the rotation axis L2 and the angular position around the third arm rotation axis L3 of the third arm 13, the tip end portion 11b of the first arm 11 and the first position on the first phantom spherical surface S1 are controlled. The tip 12b of the two arms 12 and the tip 13b of the third arm 13 are moved. As a result, the distal end portion 11b of the first arm 11, the distal end portion 12b of the second arm 12, and the distal end portion 13b of the third arm 13 define a first virtual circle C1 passing therethrough.

  And if the front-end | tip part 11b of the 1st arm 11, the front-end | tip part 12b of the 2nd arm 12, and the front-end | tip part 13b of the 3rd arm 13 prescribe | regulate the 1st virtual circle C1, the 1st connection mechanism 4 will become the 2nd virtual circle. The fourth arm 21, the fifth arm 22, and the sixth arm 23 are rotated so that C2 extends in parallel with the first virtual circle C1, and the fourth arm 21, the fifth arm 22, and the sixth arm are rotated. The base end portions 21a, 22a, and 23a of 23 are moved. Accordingly, the intermediate plate 20 moves so as to be positioned symmetrically with the fixed plate 10 with respect to the first symmetry plane.

  And if the 2nd virtual circle C2 is prescribed | regulated by the base end part 21a, 22a, 23a of the 4th arm 21, the 5th arm 22, and the 6th arm 23, the 4th virtual circle C4 will be 4th arm simultaneously with this. 21, the fifth arm 22, and the distal end portions 21 b, 22 b, and 23 b of the sixth arm 23.

  And if the 4th virtual circle C4 is prescribed | regulated by the front-end | tip part 21b, 22b, 23b of the 4th arm 21, the 5th arm 22, and the 6th arm 23, the 2nd connection mechanism 5 will be the 5th virtual circle C5. The tip portions 31b, 32b, and 33b of the seventh arm 31, the eighth arm 32, and the ninth arm 33 are moved so as to extend in parallel with the fourth virtual circle C4. As a result, the output plate 30 moves so as to be positioned symmetrically with the intermediate plate 20 with respect to the second symmetry plane. Here, since the first symmetry plane and the second symmetry plane extend in parallel with each other, the output plate 30 extending through the two symmetry planes extending in parallel with the fixed plate 10 is fixed to the fixed plate 10. And keep parallel.

  As described above, in the present embodiment, the robot arm 100 is configured such that the arm driving mechanism 6 rotates the first arm 11, the second arm 12, and the third arm 13 to rotate the fixed plate 10, the output plate 30, and the like. Is a robot arm having three degrees of freedom of translation, which can move the output plate 30 while maintaining a state in which they extend in parallel.

  As described above, in the robot arm 100 of the present invention, the distal ends of the first arm 11, the second arm 12, and the third arm 13 of the first subunit 1 are the fourth of the second subunit 2, respectively. The first arm 11 and the second arm 12 are connected to the base end portions of the arm 21, the fifth arm 22, and the sixth arm 23 by the first connection mechanism 4 that is an RBR type rotary joint. By rotating the third arm 13, the fourth arm 21, the fifth arm 22, and the sixth arm 23 can be rotated to move the intermediate plate 20 relative to the fixed plate 10. it can. The distal ends of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 2 are respectively the seventh arm 31, the eighth arm 32, and the ninth arm 33 of the third subunit 3. Are connected by the second connecting mechanism 5 which is an R-B-R type rotary joint, so that the fourth arm 21, the fifth arm 22, and the sixth arm 23 are rotated and the intermediate plate 20 is rotated. Is moved, the seventh arm 31, the eighth arm 32, and the ninth arm 33 are rotated in conjunction with this, and the output plate 30 can be relatively moved. Since the extension of the first to ninth arms in the direction orthogonal to the extending direction of the robot arm 100 can be suppressed, the robot arm 100 can be reduced in size.

(Embodiment 2)
FIG. 6 is a perspective view showing a configuration example of the robot arm 200 according to the second embodiment of the present invention, and shows a first state in which the robot arm 200 is contracted. FIG. 7 is a perspective view illustrating a configuration example of the robot arm 200, and is a diagram illustrating a second state in which the output plate 30 is moved from the position in the first state. The second state is a state in which the output plate of the robot arm 200 is positioned at a position relatively different from the first state with respect to the fixed plate. FIG. 8 is a diagram schematically illustrating a configuration example of the robot arm 200. In the first embodiment, the robot arm 100 has one second subunit 2, but in the present embodiment, the robot arm 200 includes an odd number of second subunits 2.

  That is, in the present embodiment, the robot arm 200 includes three second subunits 202A, 202B, and 202C, as shown in FIGS. Since the configuration of the second subunits 202A, 202B, 202C is the same as that of the second subunit 2, the description thereof is omitted.

  The second subunit 202A and the second subunit 202B are connected by the third connecting mechanism 204. In addition, the second subunit 202B and the second subunit 202C are connected by a fourth connecting mechanism 205. The configuration of the third coupling mechanism 204 and the fourth coupling mechanism 205 is the same as that of the first coupling mechanism 4, and therefore the description thereof is omitted. The planes extending from the first bending axis Lb1, the second bending axis Lb2, and the third bending axis Lb3 of the third coupling mechanism 204 and the fourth coupling mechanism 205 are tangent to the intermediate symmetry planes Fa and Fb. Is configured.

[Operation example]
The control unit of the robot drives the arm driving mechanism 6, and the angular position of the first arm 11 around the first arm rotation axis L 1, the angular position of the second arm 12 around the second arm rotation axis L 2, and the first By controlling the angular position of the three arms 13 around the third arm rotation axis L <b> 3, the distal end portion 11 b of the first arm 11 and the distal end of the second arm 12 on the first phantom spherical surface S <b> 1 of the first subunit 1. The part 12b and the tip 13b of the third arm 13 are moved. As a result, the distal end portion 11b of the first arm 11, the distal end portion 12b of the second arm 12, and the distal end portion 13b of the third arm 13 define a first virtual circle C1 passing therethrough.

  When the first virtual circle C1 is defined by the distal end portion 11b of the first arm 11, the distal end portion 12b of the second arm 12, and the distal end portion 13b of the third arm 13, the first coupling mechanism 4 is The fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202A are rotated so that the second virtual circle C2 of the subunit 202A extends in parallel with the first virtual circle C1, These base end portions 21a, 22a, and 23a are moved. Accordingly, the intermediate plate 20 of the second subunit 202A moves so as to be positioned symmetrically with the fixed plate 10 with respect to the first symmetry plane of the first coupling mechanism 4.

  Then, when the second virtual circle C2 of the second subunit 202A is defined by the base ends 21a, 22a, and 23a of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202A, At the same time, the fourth virtual circle C4 is defined by the fourth arm 21, the fifth arm 22, and the tip portions 21b, 22b, and 23b of the sixth arm 23 of the second subunit 202A.

  When the fourth virtual circle C4 is defined by the tip portions 21b, 22b, and 23b of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202A, the third coupling mechanism 204 is The fourth arm 21, the fifth arm 22, and the second arm of the second subunit 202 </ b> B so that the second virtual circle C <b> 2 of the second subunit 202 </ b> B extends in parallel with the fourth virtual circle C <b> 4 of the second subunit 202 </ b> A. The six arms 23 are rotated to move the base end portions 21a, 22a, and 23a. Accordingly, the intermediate plate 20 of the second subunit 202B moves so as to be positioned symmetrically with the intermediate plate 20 of the second subunit 202A with reference to the intermediate symmetry plane Fa of the third coupling mechanism 204.

  Then, when the second virtual circle C2 of the second subunit 202B is defined by the base ends 21a, 22a, and 23a of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202B, At the same time, the fourth virtual circle C4 is defined by the fourth arm 21, the fifth arm 22, and the distal end portions 21b, 22b, and 23b of the sixth arm 23 of the second subunit 202B.

  Then, when the fourth virtual circle C4 is defined by the tip portions 21b, 22b, and 23b of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202B, the third coupling mechanism 204 is The fourth arm 21, the fifth arm 22 and the second arm 202C of the second subunit 202C are arranged so that the second virtual circle C2 of the second subunit 202C extends in parallel with the fourth virtual circle C4 of the second subunit 202B. The six arms 23 are rotated to move the base end portions 21a, 22a, and 23a. Accordingly, the intermediate plate 20 of the second subunit 202C moves so as to be positioned symmetrically with the intermediate plate 20 of the second subunit 202B with reference to the intermediate symmetry plane Fb of the fourth coupling mechanism 205.

  Then, when the second virtual circle C2 of the second subunit 202C is defined by the base ends 21a, 22a, and 23a of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202C, At the same time, the fourth virtual circle C4 is defined by the fourth arm 21, the fifth arm 22, and the tip portions 21b, 22b, and 23b of the sixth arm 23 of the second subunit 202C.

  Then, when the fourth virtual circle C4 is defined by the tip portions 21b, 22b, and 23b of the fourth arm 21, the fifth arm 22, and the sixth arm 23 of the second subunit 202C, the second coupling mechanism 5 is The distal ends 31b, 32b, and 33b of the seventh arm 31, the eighth arm 32, and the ninth arm 33 are arranged so that the fifth virtual circle C5 extends in parallel with the fourth virtual circle C4 of the second subunit 202C. Move. Accordingly, the output plate 30 moves so as to be positioned symmetrically with the intermediate plate 20 of the second subunit 202C with reference to the second symmetry plane of the second coupling mechanism 5. Here, the first symmetry plane of the first coupling mechanism 4, the intermediate symmetry plane of the third coupling mechanism 204, the intermediate symmetry plane of the fourth coupling mechanism 205, and the second symmetry plane of the second coupling mechanism 5 are parallel to each other. Since it extends, the output plate 30 extending through the even number of symmetry planes extending parallel to the fixed plate 10 remains parallel to the fixed plate 10.

  Thus, by providing an odd number of second subunits 2 between the first subunit 1 and the third subunit 3, the dimensions of the robot arm 100 can be extended in the direction in which the robot arm 100 extends. it can.

(Embodiment 3)
In the first embodiment, the robot arm 100 may include a turning mechanism for turning the fixed plate 10 around the turning axis.

(Embodiment 4)
In the first embodiment, the robot arm 100 extends so that the arm of the second subunit 2 is folded with respect to the arm of the first subunit 1, and the arm of the third subunit 3 is the second subunit 2. However, instead of this, the arm of the second subunit 2 extends in the same direction as the arm of the first subunit 1, as shown in FIGS. The arm of the third subunit 3 may be provided so as to extend in the same direction as the arm of the second subunit 2. That is, as viewed from above, the first to ninth arms may be provided so as to extend to one side in the circumferential direction around the first center point O1.

(Embodiment 5)
FIG. 11A is a diagram showing a configuration example of a robot arm according to Embodiment 5 of the present invention. 11A shows a perspective view 1 of the first state of the robot arm, the upper center shows a front view of the robot arm in the first state, and the upper right side shows the robot arm. 2 is a perspective view 2 of the first state of the robot arm, the left side of the middle stage is a right side view of the first state of the robot arm, and the center of the middle stage is a plan view of the first state of the robot arm. The left side of the first state of the robot arm is shown on the right side of the middle stage, the perspective view 3 of the first state of the robot arm is shown on the left side of the lower stage, and the robot arm is shown in the lower center. A rear view of the first state is shown, and a perspective view 4 of the first state of the robot arm is shown on the lower right side. The first state is a state in which the robot arm according to the present embodiment is contracted.

  FIG. 11B is a diagram showing a configuration example of a robot arm according to Embodiment 5 of the present invention. 11B shows a perspective view 1 of the second state of the robot arm on the left side of the upper stage, FIG. 11B shows a front view of the second state of the robot arm at the center of the upper stage, and shows the robot arm on the right side of the upper stage. Fig. 2 is a perspective view 2 of the second state of the robot arm, the right side view of the second state of the robot arm is shown on the left side of the middle stage, and the plan view of the second state of the robot arm is shown at the center of the middle stage. The left side view of the second state of the robot arm is shown on the right side of the middle stage, and the perspective view 3 of the second state of the robot arm is shown on the lower side of the lower stage. A rear view of the second state is shown, and a perspective view 4 of the second state of the robot arm is shown on the lower right side. The second state is a state where the output plate of the robot arm according to the present embodiment is located at a position relatively different from the first state with respect to the fixed plate.

  FIG. 11C is a diagram illustrating a configuration example of the robot arm according to Embodiment 5 of the present invention. 11C shows a perspective view 1 of the third state of the robot arm on the left side of the upper stage, FIG. 11C shows a front view of the third state of the robot arm at the center of the upper stage, and shows the robot arm on the right side of the upper stage. FIG. 2 is a perspective view 2 of the third state of the robot arm, the left side of the middle stage is a right side view of the third state of the robot arm, and the center of the middle stage is a plan view of the third state of the robot arm. The left side view of the third state of the robot arm is shown on the right side of the middle stage, the perspective view 3 of the third state of the robot arm is shown on the left side of the lower stage, and the robot arm is shown in the center of the lower stage. A rear view of the third state is shown, and a perspective view 4 of the third state of the robot arm is shown on the lower right side. The third state is a state in which the output plate of the robot arm according to the present embodiment is located at a position relatively different from the first state and the second state with respect to the fixed plate.

  11A, 11B, and 11C, a bearing and a shaft that rotatably connect each arm and each connecting piece, a bearing and a shaft that rotatably connect the connecting pieces at each connecting portion, In addition, bearings and shafts that rotatably connect the plates and the arms are omitted.

  Since the configuration of the robot arm according to the fifth embodiment is the same as that of the robot arm according to the first embodiment, description thereof is omitted.

(Embodiment 6)
FIG. 12A is a diagram showing a configuration example of a robot arm according to Embodiment 6 of the present invention. 12A shows a perspective view 1 of the first state of the robot arm, the upper right side shows a perspective view 2 of the first state of the robot arm, and the middle left side shows the robot arm. The right side view of the first state of the arm is shown, the front view of the first state of the robot arm is shown at the center of the middle stage, and the left side view of the first state of the robot arm is shown on the right side of the middle stage. The lower part shows a plan view of the robot arm in the first state. The first state is a state in which the robot arm according to the present embodiment is contracted.

  FIG. 12B is a diagram showing a configuration example of a robot arm according to Embodiment 6 of the present invention. 12B shows a perspective view 1 of the second state of the robot arm on the upper left side of FIG. 12B, and FIG. 12B shows a perspective view 2 of the second state of the robot arm on the upper right side. The right side view of the second state of the arm is shown, the front view of the second state of the robot arm is shown in the middle center, and the left side view of the second state of the robot arm is shown on the right side of the middle stage. The lower part shows a plan view of the robot arm in the second state. The second state is a state where the output plate of the robot arm according to the present embodiment is located at a position relatively different from the first state with respect to the fixed plate.

  FIG. 12C is a diagram illustrating a configuration example of the robot arm according to Embodiment 6 of the present invention. 12C shows a perspective view 1 of the third state of the robot arm on the upper left side of FIG. 12C, and FIG. 12C shows a perspective view 2 of the third state of the robot arm on the upper right side. The right side view of the third state of the arm is shown, the front view of the third state of the robot arm is shown at the center of the middle stage, and the left side view of the third state of the robot arm is shown on the right side of the middle stage. The lower part shows a plan view of the robot arm in the third state. The third state is a state in which the output plate of the robot arm according to the present embodiment is located at a position relatively different from the first state and the second state with respect to the fixed plate.

  In FIGS. 12A, 12B, and 12C, the bearing and shaft that rotatably connect the fixing plate of the first subunit and the first to third arms and the arm drive mechanism are omitted.

  Since the configuration of the robot arm according to the sixth embodiment is the same as that of the robot arm according to the fourth embodiment, description thereof is omitted.

(Embodiment 7)
FIG. 13 is a diagram showing a configuration example of a robot arm 700 according to Embodiment 7 of the present invention. In FIG. 13, a bearing and a shaft that rotatably connect the fixing plate of the first subunit and the first to third arms and the arm driving mechanism are omitted.

  In the second embodiment, the robot arm 200 has three second subunits 202A, 202B, and 202C. However, in the present embodiment, the robot arm 700 has five second subunits 702A and 702B. , 702C, 702D, and 702E. The configuration of each second subunit and the configuration of the connecting mechanism that connects the second subunits to each other are the same as the configurations in the second embodiment, and a description thereof will be omitted.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  The present invention can be applied to a robot for processing and transporting articles.

C1 1st virtual circle C2 2nd virtual circle C3 3rd virtual circle C4 4th virtual circle C5 5th virtual circle C6 6th virtual circle F1 1st plane F2 2nd plane F3 3rd plane L1 1st arm rotation axis L2 Second arm pivot axis L3 Third arm pivot axis L4 Fourth arm pivot axis L5 Fifth arm pivot axis L6 Sixth arm pivot axis L7 Seventh arm pivot axis L8 Eighth arm pivot axis L9 First 9-arm rotation axis O1 1st center point O2 2nd center point O3 3rd center point S1 1st virtual spherical surface S2 2nd virtual spherical surface S3 3rd virtual spherical surface 1 1st subunit 2 2nd subunit 3 3rd subunit 4 First connection mechanism 5 Second connection mechanism 6 Arm drive mechanism 10 Fixed plate 11 First arm 12 Second arm 13 Third arm 20 Intermediate plate 21 Fourth arm 22 Fifth arm 23 Sixth Over arm 30 output plate 31 seventh arm 32 eighth arms 33 ninth arm 41 first connecting portion 42 a second connecting portion 43 third connecting portion 44 fourth connecting portion 45 fifth connecting portion 46 sixth connecting portion 100 the robot arm

Claims (6)

The fixed plate extending in parallel to the first plane including the first to third arm rotation axes intersecting at the first center point, and the fixed portion so that the base end portion is rotatable about the first arm rotation axis. A first arm connected to the plate, a second arm connected to the fixed plate so that a base end is rotatable about the second arm rotation axis, and a base end is connected to the third arm. And a third arm coupled to the fixed plate so as to be rotatable around a movement axis, and the distal ends of the first to third arms as the first to third arms rotate. Is configured to move on a first phantom spherical surface centered on the first center point , and configured to change a diameter of a phantom circle passing through the tip portions of the first to third arms. A first subunit,
The intermediate plate extending parallel to the second plane including the fourth to sixth arm rotation axes intersecting at the second center point and the intermediate portion between the base end portion and the distal end portion are the fourth arm rotation. A fourth arm connected to the intermediate plate so as to be rotatable around an axis, and an intermediate portion between a base end portion and a distal end portion are provided on the intermediate plate so as to be rotatable around the fifth arm rotation axis. A fifth arm that is connected, and a sixth arm that is connected to the intermediate plate so that an intermediate portion between the base end portion and the distal end portion can rotate about the sixth arm rotation axis. Then, as the fourth to sixth arms rotate, the distal end portions and the proximal end portions of the fourth to sixth arms move on the second phantom spherical surface centered on the second center point. A second subunit configured as:
An output plate extending parallel to a third plane including the seventh to ninth arm rotation axes intersecting at the third center point, and the output so that a base end portion can rotate about the seventh arm rotation axis A seventh arm connected to the plate, an eighth arm connected to the output plate so that a base end is rotatable about the eighth arm rotation axis, and a base end is connected to the ninth arm. A ninth arm coupled to the output plate so as to be rotatable about a movement axis, and the distal end portions of the seventh to ninth arms by rotating the seventh to ninth arms. And a third subunit configured to move on a third phantom spherical surface centered on the third center point,
The distal ends of the first to third arms of the first subunit are connected to the base ends of the fourth to sixth arms of the second subunit by R-B-R type rotary joints, respectively. And
The distal ends of the fourth to sixth arms of the second subunit are connected to the distal ends of the seventh to ninth arms of the third subunit by R-B-R type rotary joints, respectively. Robot arm.   The fixed plate and the intermediate plate are configured to be symmetrically located with respect to a predetermined first symmetry plane, and the intermediate plate and the output plate are predetermined to extend in parallel with the first symmetry plane. The robot arm according to claim 1, wherein the robot arm is configured to be positioned symmetrically with respect to the second symmetry plane. An R-B-R type rotary joint connecting the distal end portions of the first to third arms of the first subunit and the proximal end portions of the fourth to sixth arms of the second subunit. Each includes a fixed-side connecting piece and an intermediate-side first connecting piece connected to the fixed-side connecting piece so as to be rotatable around a bending axis, and the fixed-side connecting piece has the first center point. The intermediate first connecting piece passes through the second center point and passes through the bending axis, and is connected to the distal ends of the first to third arms so as to be rotatable around an axis orthogonal to the bending axis. Connected to the base ends of the fourth to sixth arms so as to be rotatable around an axis perpendicular to the axis,
An R-B-R type rotary joint connecting the distal ends of the fourth to sixth arms of the second subunit and the distal ends of the seventh to ninth arms of the third subunit is , Each of the intermediate side second connection pieces, and an output side connection piece connected to the intermediate side second connection piece so as to be rotatable around a bending axis. The output side connecting piece passes through the third center point and is bent, and is connected to tip ends of the fourth to sixth arms so as to be rotatable about an axis passing through a center point and orthogonal to the bending axis. 3. The robot arm according to claim 1, wherein the robot arm is connected to tip portions of the seventh to ninth arms so as to be rotatable around an axis perpendicular to the axis. 4. A first drive section for driving the first arm to rotate about the first arm rotation axis;
A second drive section for driving the second arm to rotate around the second arm rotation axis;
The robot arm according to any one of claims 1 to 3, further comprising: a third driving unit that drives the third arm to rotate about the third arm rotation axis. An odd number of the second subunits;
The odd number of second subunits are arranged in a row, and the base ends of the fourth to sixth arms of the second subunit adjacent to the distal ends of the fourth to sixth arms of one second subunit. Are connected to each other by an R-B-R type rotary joint,
The distal ends of the first to third arms of the first subunit are respectively the fourth to sixth of the second subunit located at one end of the second subunit connected to each other. It is connected to the base end of the arm by a RBR type rotary joint,
The distal ends of the fourth to sixth arms of the second subunit located at the other end of the second subunit connected to each other are respectively connected to the seventh to ninth of the third subunit. The robot arm according to any one of claims 1 to 4, wherein the robot arm is connected to the tip of the arm by an RBR type rotary joint.   The robot arm according to claim 1, further comprising a turning mechanism for turning the fixed plate about a turning axis.

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