JPH0232120B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flexible arm used in industrial robots and the like.

A column is rotatably attached to a support base, an arm is attached to one end of the column so that it can rotate (swing), and a painting nozzle, for example, is attached to the tip of the arm, and the nozzle can be freely operated by rotating the column and swinging the arm. There are known robots that automatically set themselves to the desired position and perform painting work.

By the way, the arms used in this type of robot are generally not bendable, so it is relatively difficult to set the nozzle to any desired position.
A robot having such an arm can only be applied to a workpiece having a simple shape, and is not very versatile.

On the other hand, recently, various bendable flexible arms have been proposed, but all of them have complicated structures, and if the arm is relatively long, it will bend due to the weight of the arm itself, and the nozzle will not be able to hold the nozzle in a predetermined position. is difficult to set, and if this were to be dealt with, a member with extremely high rigidity would have to be used, which would be impractical.

Furthermore, in the conventionally proposed flexible arms, it is difficult to obtain a sufficient amount of deformation relative to the amount of operation caused by the working device, and it is difficult to make maximum use of the effect of bendability.

The present invention has been made in view of the above points,
The aim is to provide a flexible arm with favorable bending performance. An object of the present invention is to provide a first hook joint having two orthogonal axes, a first axis and a second axis orthogonal to each other, a third axis substantially parallel to the first axis, and a second axis substantially parallel to the first axis. a second hook joint having two orthogonal axes with a fourth axis substantially parallel to the axis; a first rigid segment connected to the first axis; and one end connected to the second axis. With,
a second rigid body segment whose other end is connected to the third axis; a third rigid body segment whose other end is connected to the fourth axis; and a second rigid body segment that is movable along the second axis and around the second axis. a first sliding member rotatably connected to a second shaft, one end of which is rotatably connected to a first rigid body node about an axis parallel to the first shaft; a first link member rotatably connected to the first sliding member around an axis parallel to the first axis;
a second sliding member connected to the fourth axis so as to be movable along the axis and rotatable about the fourth axis, and one end of which is rotatable about an axis parallel to the third axis; a second link member that is connected to the second rigid body segment and whose other end is rotatably connected to the second sliding member about an axis parallel to the third axis; a first input link member connected to an intermediate portion of the first link member and configured to translate along the center axis on the first shaft side of the first hook joint; a third sliding member coupled to the second shaft so as to be movable along the second axis together with the member and rotatable about the second axis independently of the first sliding member; , one end is connected to a third sliding member rotatably around an axis parallel to the third axis, and the other end is connected to a second link rotatably around an axis parallel to the third axis. a third link member connected to the intermediate portion of the member; and a fourth sliding member connected to the first axis so as to be movable along the first axis and rotatable about the first axis. and a fourth rigid body node, one end of which is rotatably connected to the second rigid body node around an axis parallel to the second axis, and the other end of which is rotatably connected to the second rigid body node around an axis parallel to the second axis. a fourth link member connected to the sliding member; a fifth sliding member connected to the third axis so as to be movable along the third axis and rotatable about the third axis; , one end is connected to a fifth sliding member rotatably around an axis parallel to the fourth axis, and the other end is connected to a third sliding member rotatably around an axis parallel to the fourth axis.
a fifth link member connected to the rigid body node; a second input link member connected at one end to the fourth sliding member and configured to translate along the aforementioned central axis; a sixth shaft coupled to the third shaft so as to be movable along the third axis together with the fifth sliding member and rotatable about the third axis independently of the fifth sliding member; a sliding member, one end of which is connected to a sixth sliding member so as to be rotatable around an axis parallel to the second axis, and the other end rotatable around an axis parallel to the second axis. and a sixth link member connected to the intermediate portion of the fourth link member.

Next, a preferred specific example of the present invention will be explained based on the drawings.

Incidentally, FIG. 1 shows a schematic diagram of the principle, and the following explanation will be easier to understand by referring to FIG.

In the figure, in this specific example, there are four rigid body nodes 1 to 4.
The rigid body nodes are similarly configured and connected in the same way, and rigid body nodes 1 and 2 will be described below. The rigid body sections 1 and 2 have cylindrical frames 5 and 6, respectively, and a shaft 7 is attached to the frame 5 so as to be rotatable in the A ₂ direction and _the B ₂ direction. direction and
A sliding member 8 is attached so as to be rotatable in _two directions B and movable in _one direction C and _one direction D, that is, slidably. A mounting member 11 is rotatably attached to the sliding member 8 by a washer 9 and a retaining ring 10, and a link member 13 is rotatably connected to the member 11 via a shaft 12. axis 7
A pin 14 is provided on the frame 5 in parallel with the frame 5, a connecting member 15 is fixed to the pin 14, a pin 16 is attached to the connecting member 15 orthogonal to the pin 14, and the pin 16 is attached to both ends. It is supported by frame 5. The link member 1 is rotatably attached to the pin 16.
7 are connected to each other, and a link member 13 is rotatably connected to the link member 13 approximately in the middle of the link member 17 via a shaft 18.
are connected. The link member 17 is attached to the shaft 1 at the other end.
It is rotatably connected to the mounting member 20 via 9. The attachment member 20 is rotatably attached to the sliding member 23 by a washer 21 and a retaining ring 22, and the sliding member 23 has an attachment member 2 corresponding to the member 11 used for connection with the rigid section 3.
4 is rotatably attached. A sliding member 23 corresponding to the member 8 is slidably attached to a shaft 25 parallel to the shaft 7, like the member 8, and is attached to the shaft 25 parallel to the shaft 7.
Similar to the shaft 7, the A ₂ direction and the B ₂ direction are attached to the frame 6 at both ends.
It is rotatably supported in the direction. A shaft 26 perpendicular to the shaft 25 has an enlarged portion 27a approximately at the center, and the shafts 26 and 25 are connected at the enlarged portion 27a. A sliding member 27b is slidably attached to the shaft 26, and members 8, 2 are attached to the sliding member 27b.
Similarly to 3, mounting members 30 and 31 are rotatably mounted by washers 28 and retaining rings 29, and a link member 33 is rotatably connected to the mounting member 31 via a shaft 32. pin 1
A link member 34 is rotatably connected to 4, and one end of a link member 33 is rotatably connected to the middle of the link member 34 via a shaft 35. The link member 34 is connected to the attachment member 36 at one end.
The mounting member 36 is rotatably connected to the sliding member 40 by a washer 38 and a retaining ring 39 through a shaft 37.

The sliding member 40 is slidably attached to the shaft 41 in the same way as the members 8, 23, and 27b.
An enlarged portion 42 is formed approximately in the center of the shaft 41 , and the shaft 41 and the shaft 7 perpendicular to the shaft 41 are connected at the enlarged portion 42 . The shaft 41 is rotatably supported by a cylindrical base frame 44a having side plates 43 at both ends, and the side plates 43 are fixed approximately at the center to a spline shaft 44b. Base frame 4 parallel to axis 41
A pin 45 supported by 4a is orthogonal to a pin 46, and the pin 46 is supported at both ends by a base frame 44a that constitutes the rigid section of the front plate of the rigid section 1.

A connecting member 47 is fixed approximately at the center of the pin 46, and the pin 45 is attached to the connecting member 47. A link member 48 is rotatably attached to the pin 46, the link member 48 is rotatably connected to a link member 50 via a shaft 49, and the link member 50 is rotatably connected to a mounting member 51 via a shaft 50a. is rotatably connected to. The mounting member 51 is attached to the sliding member 40 similarly to the member 36.
It is rotatably attached to the The link member 48 is rotatably connected to a link member 53 via a shaft 52, and the link member 53 is rotatably connected to a link member 55 via a shaft 54. The link member 55 is attached to a sliding member 57 by bolts 56, and the sliding member 57 is attached to a flange 58.
It consists of a cylindrical member 59 having a cylindrical member 59 and an annular member 60 screwed onto the cylindrical member 59. The cylindrical member 59 meshes with the spline shaft 44b, and the spline shaft 44b is rotated about the center line 61. While being rotated in the same manner as , it is slidable in the E direction and the F direction relative to the spline shaft 44b. An annular member 62 is attached to the sliding member 57, and needle bearings 63 and 64 are provided between the annular member 62 and the flange 58 and the annular member 60.
2 is rotatable about the center line 61 with respect to the cylindrical member 59. One end of a piston rod 66 is screwed onto a protrusion 65 protruding from the annular member 62, and the other end of the rod 66 is connected to a piston of a hydraulic cylinder (not shown). A link member 69 is rotatably connected via a shaft 68 to a mounting member 67 rotatably attached to the sliding member 8 in the same manner as the member 11, and the link member 69 is rotatably connected to the pin 45 at one end. freely connected. A pin 46 parallel to the axis 7 connects to the base frame 44a at both ends.
is supported by A link member 71 is rotatably connected to approximately the middle of the link member 69 via a shaft 70, and the link member 71 is rotatably connected to a link member 73 via a shaft 72.
The link member 73 is attached to the sliding member 75 via a bolt 74 at one end, and the link member 73 is attached to the sliding member 75 via a bolt 74.
is formed similarly to the member 57, and the cylindrical member 7
The annular member 81 is mounted between the flange 77 of No. 6 and the annular member 78 via needle bearings 79 and 80, and has a protrusion 82.
One end of a piston rod 83 is screwed onto the piston 2, and the other end of the rod 83 is connected to a piston of another hydraulic cylinder (not shown). The cylindrical member 76 meshed with the spline shaft 44b is rotated with the rotation of the spline shaft 44b about the center line 61, and is slidable in the E direction and the F direction with respect to the spline shaft 44b. The annular member 81 is rotatable with respect to the sliding member 75, and even if the sliding member 75 is rotated, the annular member 81 is not rotated. Spline shaft 44b
is connected to the rotary actuator 84, and when oil pressure is supplied to the rotary actuator 84, the spline shaft 44b moves toward the center line 61.
Rotate clockwise or counterclockwise around .

Hereinafter, the configuration of the present invention will be explained based on the constituent elements of the above-described specific examples of the present invention.

That is, the flexible arm of the present invention has two orthogonal axes 41, the first axis 41 and the second axis 7, which are orthogonal to each other.
7 and two orthogonal axes 26, a third axis 26 substantially parallel to the first axis 41 and a fourth axis 25 substantially parallel to the second axis 7; 2
5, a first rigid section 44a connected to the first shaft 41, one end connected to the second shaft 7, and the other end connected to the third shaft 2.
6 and a fourth shaft 25
a third rigid section 2 connected to the second shaft 7; and a first sliding member connected to the second shaft 7 so as to be movable along the second shaft 7 and rotatable about the second shaft 7. 8,
67, one end is connected to the first rigid body section 44a so as to be rotatable around an axis line parallel to the first axis 41, and the other end is rotatable around an axis line parallel to the first axis 41. a first link member 69 connected to the first sliding members 8, 67; and a fourth shaft 25.
a second sliding member 23 connected to the fourth shaft 25 so as to be movable along the axis and rotatably around the fourth axis 25; a second link member that is rotatably connected to the second rigid body segment 1 and whose other end is rotatably connected to the second sliding member 23 around an axis parallel to the third axis 26; 17, and a first input link member having one end connected to the intermediate portion of the first link member 69 and configured to translate along the central axis on the first axis side of the first hook joint. 71
and the second shaft 7 together with the first sliding members 8, 67.
The first sliding member 8, 67 is movable along the
The second
a third sliding member 8, 11 connected to the shaft 7;
One end is connected to the third sliding member 8, 11 so as to be rotatable around an axis parallel to the third shaft 26, and the other end is rotatable around an axis parallel to the third shaft 26. The third link member 13 is connected to the intermediate portion of the second link member 17, and the third link member 13 is connected to the first shaft 41 so as to be movable along the first shaft 41 and rotatable around the first shaft 41. The connected fourth sliding members 40 and 36 have one end connected to the second rigid body section 1 rotatably around an axis parallel to the second axis 7, and the other end connected to the second rigid body section 1. A fourth link member 34 rotatably connected to the fourth sliding members 40 and 36 around an axis parallel to the shaft 7, and a third shaft 2.
6, and a fifth sliding member 27b, 30 connected to the third shaft 26 so as to be movable along the axis 6 and rotatably around the third shaft 26; The fifth sliding member is connected to the fifth sliding member so as to be rotatable about the same, and the other end is connected to the third rigid body section 2 so as to be rotatable about the axis parallel to the fourth axis 25. a link member, a second input link member 50 whose one end is connected to the first shaft 41 and configured to translate along the aforementioned central axis, and fifth sliding members 27b, 30. together with a fifth sliding member 2 movable along the third axis;
A sixth sliding member 27b, 31 is connected to the third shaft 26 so as to be rotatable around the third shaft 26 independently of the third shaft 7b, 30; a sixth sliding member 27b rotatably around the
31, and the other end is rotatably connected to the fourth link member 3 around an axis parallel to the second shaft 7.
4 and a sixth link member 33 connected to the intermediate portion of the flexible arm.

The operation of the flexible arm configured in this way will be explained. When oil pressure is supplied to the actuator 84 and the shaft 44b is rotated about the center line 61, the base frame 44a is rotated, and thereby the shaft 7
and 41, the rigid body segment 1 is rotated, and then the rigid body segments 2, 3, and 4 are sequentially rotated about the center line 61. Then rigid body section 4
For example, if a paint spray nozzle is attached to the tip of the rigid body section 4, the nozzle is rotated together with the rigid section 4. When hydraulic pressure is supplied to one hydraulic cylinder and the rod 66 is moved in the E direction, the sliding member 57 moves toward the shaft 44.
b in the E direction, and the link member 55 is also moved in the E direction. As the link member moves in the E direction, the link member 48 is rotated in the _A2 direction via the link member 53, and the link member 50
The sliding member 40 is moved in the _C2 direction.
As the sliding member 40 moves in the _C2 direction, a force in the _C2 direction is applied to the pin 14 via the link member 34.
As a result, the frame 5 is rotated about the axis 7 in the _A2 direction. As the frame 5 rotates in the _A2 direction, the link member 34 is rotated in the _A2 direction about the shaft 37, so that the link member 33 is moved in the G direction and the sliding member 27b is moved in the _C2 direction. As the sliding member 27 moves in the _C2 direction, the frame 6 is rotated in the _A2 direction about the shaft 25 in the same manner as described above.
Thereafter, the frames of the rigid body sections 3 and 4 are successively rotated in the _A2 direction, so that the flexible arm is bent upward as a whole in FIG. Therefore, when a nozzle is attached to the tip of the rigid section 4, the nozzle is set in a bent position. Conversely, when the rod 66 is moved in the F direction, the sliding member 40 is moved in the _D2 direction, and the frame 5 is rotated about the axis 7 in the _B2 direction, so that the other frames are also moved in the _B2 direction. Rotated, the flexible arm is bent generally downwardly in FIG. When hydraulic pressure is supplied to the other hydraulic cylinder and the rod 83 is moved in the E direction, the sliding member 7
5 is moved in the E direction along the shaft 44, and the link member 73 is also moved in the E direction. As the link member 73 moves in the E direction, the link member 69 is rotated in the _B1 direction about the shaft 45 via the link member 71, so that the _D1 of the sliding member 8
B ₁ centered on axis 41 to axis 7 with movement in direction
A rotational force in the direction is applied, which causes the frame 5 to align with the axis 41.
It is rotated in the _B1 direction around . As a result of the rotation of the frame 5 in the _B1 direction and the movement of the link member 13 in the H direction, the link member 17 is rotated in the _B1 direction about the pin 16, and the sliding member 23 is moved in the _D1 direction. D When the sliding member 23 moves in _one direction, the frame 6 moves around the shaft 26 in the same way as above.
B Rotated in _one direction. Thereafter, the frames of the rigid body sections 3 and 4 are successively rotated in the _B1 direction, so that the flexible arm is bent downward as a whole in FIG. Conversely, when the rod 83 is moved in the F direction, the shaft 7 rotates in the _A1 direction about the axis 41, and the sliding member 8 is moved in the _C1 direction, causing the frame 5 to rotate in the A1 direction about the axis ₄₁ . As a result of being rotated in the A1 direction, the other frame is also rotated in the _A1 direction and the flexible arm is bent upward as a whole in FIG.

Although the specific example described above is configured with four rigid body nodes, the present invention is not limited thereto, and may be configured with one or more rigid body nodes. When a flexible arm is constituted by one rigid body joint, the base frame is regarded as one rigid body joint. Furthermore, the present invention is not limited to applications for painting, but can also be applied to, for example, welding robots.
It can also be applied to magic hands other than robots.

According to the flexible arm of the present invention, since the arm is configured to be bendable, it is possible to provide a flexible arm that can be applied to a workpiece having a complicated shape and that can increase versatility. In addition, since the arm is composed of a hook joint and a link mechanism, it does not require the use of highly rigid members.
With a simple configuration, the same effect as using a member equivalently superior in rigidity can be obtained, without bending,
The tip of the arm can be accurately positioned at a predetermined position, and in addition, a sufficient amount of bending of the arm can be obtained even with a small amount of movement of the input link member,
Furthermore, due to the reversible characteristic of the link mechanism, it can be applied to so-called teaching operations.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of the principle of a specific example of the present invention;
FIG. 2 is a side view of a preferred embodiment of the invention;
The figure is a bottom view of the specific example shown in Figure 2, and Figure 4 is the bottom view of the specific example shown in Figure 2.
It is a sectional view taken along the line shown in the figure. 1, 2, 3, 4, 5...rigid body node, 7,41...axis,
8, 40...Sliding member, 13, 17, 33, 34...
link member.

Claims (1)

[Scope of Claims] 1. A first hook joint having two orthogonal axes, a first axis and a second axis orthogonal to each other; a third axis substantially parallel to the first axis; and a third axis substantially parallel to the first axis; a second axis having two orthogonal axes, a fourth axis substantially parallel to the second axis;
a hook joint connected to the first shaft;
a second rigid body segment having one end connected to the second shaft and the other end connected to the third shaft.
a third rigid body joint connected to the fourth axis; and a third rigid body joint connected to the second axis so as to be movable along the second axis and rotatable about the second axis. A connected first sliding member, one end of which is connected to the first rigid body section rotatably around an axis parallel to the first axis, and the other end of which is connected to the first rigid body segment.
said first rotatably around an axis parallel to the axis of
a first link member coupled to the sliding member; and a second link member coupled to the fourth axis so as to be movable along the fourth axis and rotatable about the fourth axis. a sliding member, one end of which is rotatably connected to the second rigid section around an axis parallel to the third axis, and the other end rotatable around an axis parallel to the third axis; a second link member rotatably connected to the second sliding member; one end connected to an intermediate portion of the first link member; the first axis of the first hook joint; a first input link member configured to translate along a side central axis; and a first input link member configured to translate along a central axis of the side;
a third sliding member coupled to the second shaft so as to be movable along the axis and rotatable about the second shaft independently of the first sliding member; The third sliding member is connected to the third sliding member so as to be rotatable about an axis parallel to the third axis, and the other end is connected to the second sliding member so as to be rotatable about the axis parallel to the third axis. A third link member connected to the intermediate portion of the link member.
a fourth sliding member connected to the first shaft so as to be movable along the first shaft and rotatable about the first shaft, and one end of which is connected to the second shaft. The fourth sliding member is connected to the second rigid body section so as to be rotatable about an axis parallel to the axis of the fourth sliding member, and the other end is rotatable about an axis parallel to the second axis. a fourth link member connected to the third axis; and a fifth sliding member connected to the third axis so as to be movable along the third axis and rotatable about the third axis. , one end is rotatably connected to the fifth sliding member around an axis parallel to the fourth axis, and the other end is connected to the fourth sliding member.
said third rotatably around an axis parallel to the axis of
a fifth link member connected to the rigid body node; and a second input link member connected at one end to the fourth sliding member and configured to translate along the central axis; to the third axis so as to be movable along the third axis together with the fifth sliding member and rotatable about the third axis independently of the fifth sliding member; a connected sixth sliding member, one end of which is rotatably connected to the sixth sliding member around an axis parallel to the second axis, and the other end of which is connected to the second axis; a sixth link member rotatably connected to an intermediate portion of the fourth link member about parallel axes; 2. The flexible arm of claim 1, wherein the first rigid segment is configured to rotate about the central axis.