JPH0768482A - Hand holding device - Google Patents

Abstract

PURPOSE:To surely hold a hand on the side of a hand mounting table in a hand holding device to hold the hand connected to the tip of a robot arm on the hand mounting table. CONSTITUTION:In a hand holding device, a hand 2 to be connected to the tip of a robot arm 1 is held on a hand mounting table 3. This device is provided with a claw part to be brought into contact with the hand 2, and also provided with a hook 5 which is rotational around the shaft fixed to the hand mounting table 3, and a cam 11 to rotate the hook by a cam surface with the surface perpendicular to the rotary surface of the hook 5 as the rotary surface. When the cam surface at the position of the minimum radius of the cam 11 is brought into contact with the hook 5, the hook 5 is opened, and the hand 2 is mounted on the hand mounting table 3. Then, the cam 11 is rotated, the cam surface at the position of the maximum radius is brought into contact with the hook 5, and the hook 5 is closed thereby, and the hand 2 is fixed to the hand mounting table 3 by the claw part at the tip of the hook 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hand holding device for holding a hand connected to the tip of a robot arm on a hand setting table.

In recent years, space robots have been developed which perform work such as attachment / detachment of connectors and fastening of bolts on orbits in outer space. These robots are designed to handle multiple tasks by replacing multiple hands. The present invention relates to a hand holding device for holding an unused hand on a hand setting table among the plurality of hands, and particularly solves a problem peculiar to outer space. It is applicable.

[0003]

2. Description of the Related Art Conventionally, in order to replace a hand with a robot, the robot arm approaches a hand installation table and separates the hand attached to a hand attachment mechanism called a tool fixture provided at the tip of the robot arm. It is done by placing it on the hand stand and attaching a new hand to the tool fixture.

In the ground robot arm, the gravity of the hand is utilized to separate the hand from the tool fixture. Also, regarding the storage of the hand after separation, the gravity of the hand is used to restrain the hand on the hand setting table.

[0005]

However, since there is almost no gravity in outer space, it is necessary to hold the hand on the side of the hand setting table when separating the hand from the tool fixture, and to store the hand. Sometimes a holding device is needed to hold the hand on the hand stand.

Further, the joint of the space robot arm has a considerable play in consideration of the expansion and contraction of the material due to the severe temperature difference in outer space. For this reason, the positioning accuracy of the tip of the robot arm is poor, and therefore accurate positioning is required when positioning the hand to a predetermined position on the hand installation table to separate the hands or to newly mount the hand on the tool fixture. However, there is a problem that the hand cannot be replaced smoothly.

Further, since a satellite equipped with a robot is violently vibrated at the time of launch, it is necessary to fix the tip of the robot arm somewhere. The present invention has been made in order to meet such problems and demands, and an object of the present invention is to provide a hand holding device that holds a hand on the side of a hand setting table.

Another object of the present invention is to provide a hand holding device that allows the hands to be separated and mounted smoothly. Still another object of the present invention is to provide a hand holding device that can fix the tip of the robot arm when launching a satellite.

[0009]

In order to achieve the above object, the present invention, as shown in FIG. 1, holds a hand 2 for holding a hand 2 connected to the tip of a robot arm 1 on a hand setting table 3. A device is provided. This device is provided with a claw portion that comes into contact with the hand 2 and also has a hand installation table 3
It is characterized by having a hook 5 rotatable about an axis fixed to a shaft, and a cam 11 which rotates with a plane perpendicular to the plane of rotation of the hook 5 as a plane of rotation and rotates the hook 5 by a cam surface.

[0010]

In the above structure, first, when the cam surface of the cam 11 at the minimum radius position contacts the hook 5, the hook 5 is opened, and at this time, the hand 2 is mounted on the hand setting table 3. After that, the cam 11 is rotated and the cam surface at the maximum radius position contacts the hook 5, whereby the hook 5 is closed and the hand 2 is fixed to the hand setting table 3 by the claw portion at the tip of the hook 5.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a schematic configuration of a space robot arm including a hand holding device. In the figure, a hand 2 is attached to the tip of a space robot arm 1 fixed to a satellite. The hand 2 is held by the hand holding table 4 on the hand setting table 3. The hand stand 3 is fixed to the satellite. Here, it is assumed that the part of the hand 2 that contacts the hand holding device 4 has a cylindrical shape.

FIG. 2 is a plan view of the hand setting table 3 and the hand holding device 4. The hand holding device 4 is mainly 120
Three hooks 5-7 arranged at intervals, three conical guides 8-10 arranged at intervals of 120 degrees, and a cam 11
And the hand setting table 3 has a conical guide 8 ...
10 are provided.

FIG. 3 is an elevational view showing the structure of the hook 5. Since the hooks 5 to 7 have the same structure, only the structure of the hook 5 is shown, and the description of the other hooks 6 and 7 is omitted.

The hook 5 is supported on a part 3a of the hand setting table 3 by a shaft 5a and is rotatable about the shaft 5a in the directions of arrows 12 and 13. Hand 2 at one end of hook 5
Is provided with a hook-shaped claw portion 5b, and the roller 14 is connected to the other end via a roller shaft 15. Again hook 5
A coil spring 16 is provided between the convex portion 5c of FIG. 3 and the convex portion 3b of the hand setting table 3, and the coil spring 16 constantly biases the hook 5 in the direction of arrow 12.

FIG. 4 is a perspective view showing the structure of the conical guides 8-10. Each of the conical guides 8 to 10 is provided on the hand setting table 3 and has a tapered surface 8 facing the center for positioning the hand 2 at the center position of the hand setting table 3.
a, 9a, 10a (9a is not visible in FIG. 4). Further, only the conical guide 10 is further provided with a V-shaped groove portion 10b along the radial direction.

FIG. 5 is a view for explaining the cam 11.
(A) is a plan view of the cam 11, (B) is an elevation view showing the relationship between the cam 11 and the hook 5 at the OA position in (A), (C)
FIG. 7A is an elevational view showing the relationship between the cam 11 and the hook 5 at the OB position in (A).

As shown in FIG. 5A, the cam 11 has 12
It has rotational symmetry every 0 degrees, and has a cam surface at the rotation end, and the rollers 14, 16, 17 (16, 1) are provided on this cam surface.
7 is a roller connected to the hooks 6 and 7) is a coil spring 1
Due to the action of 6 etc., it is always in contact. Cam 1
The rotation surface of 1 is perpendicular to the rotation surfaces of the hooks 5 to 7, and the cam 11 is rotationally driven by a stepping motor (not shown). In addition, the cam surface of the cam 11 is perpendicular to the rotation surface in the maximum radius portion [Fig. 5 (B)],
In the minimum radius portion, the rotary surface is provided at an acute angle [FIG. 5 (C)] to improve the familiarity between the contact surface of the roller and the cam surface.

The operation of the hand holding device having the above-described structure will be described with reference to FIG. 6 which is an elevational view of the hand holding device 4 and FIGS. First, when the minimum radius portion of the cam 11 is in contact with the rollers 14, 16 and 17 and the hooks 5 to 7 are in the rotation positions as shown in FIG. 5C, the hand 2 approaches the hand setting table 3. , Tapered surfaces 8a, 9 of the conical guides 8-10 provided on the hand setting table 3
a, 10a, so that the hand 2 is positioned at the center of the hand setting table 3. At the same time, the rod-shaped guide pin 2a provided on the cylindrical side surface of the hand 2 moves to the groove bottom along the V-shaped wall surface of the groove portion 10b provided on the conical guide 10a, whereby the hand 2 rotates a predetermined amount. Be positioned in position.

Next, the cam 11 is rotated by the stepping motor. As a result, the maximum radius portion of the cam 11 comes into contact with the rollers 14, 16 and 17, and the hooks 5 to 7 are arranged as shown in FIG.
The hand 2 is fixed to the hand installation base 3 by moving to the rotation position as shown in FIG.

As described above, since the rotating surface of the cam 11 is at right angles to the rotating surfaces of the hooks 5 to 7, the transmission of force becomes irreversible, and the hooks 5 to 7 that have been closed once can be opened by vibration or the like. Rather, the hand 2 can be held reliably and with high rigidity. Therefore, the hand 2 can be easily separated from the tool fixture (not shown) of the robot arm 1 even in the space where there is almost no gravity, and the hand 2 can be securely stopped on the hand setting table 3 when the hand 2 is stored. be able to.

Further, when the hand 2 is attached to the tip of the robot arm 1 at the time of launching a satellite and the hand 2 is held on the hand setting table 3 by the hand holding device of the present invention having high rigidity, the robot arm 1 will be Fixing can be easily realized.

Even if the outer shape of the hand 2 is changed, the shape of the claws of the hooks 5 to 7 and the conical guide 8 to.
This can be dealt with only by changing the shapes of the 10 tapered surfaces 8a, 9a, 10a.

In the above hand holding device, the hook 5
If there are variations in parts dimensions such as ~ 7 and cam 11,
There is a possibility that the contact state or the pressing force of the hooks 5 to 7 on the hand 2 may not be desired. If the hooks 5 to 7 do not come into contact with the hand 2, the hand 2 cannot be held securely, and if the pressing force is excessive, the hand 2 will be destroyed. A hook that takes this into consideration will be described with reference to FIG. 7.

7A and 7B are views for explaining a hook capable of adjusting a rotational position and a pressing force, FIG. 7A is a perspective view of a hook including an adjusting means and a roller, and FIG. 7B is a cross-sectional view thereof. That is, the roller 19 is attached to the end of the hook 18.
Are connected via the roller shaft 20 and the adjusting means 21. The structure of the hook 18 is the same as that shown in FIG. 3, and the roller 19 has a cam 11 (not shown) at the upper portion of FIG.
Touch the cam surface of. The adjusting means 21 has a columnar shape, and the roller shaft 20 is fixed to one end of the adjusting means 21 at an axial position eccentric to the cylinder. Adjusting means 21
The cylindrical portion at the other end is embedded in the end portion of the hook 18 and has a slot 21a at the tip for engaging with a flat-blade screwdriver.
Is provided. Further, the lock screw 22 is provided on the hook 18 at a position where it abuts on the columnar portion at the other end of the adjusting means 21.
Is provided.

In such a structure, when a minus driver is engaged with the slide 21a and the adjusting means 21 is rotated, the roller shaft 20 moves in the vertical direction in the figure because the shaft is eccentric, and the roller 19 is rotated. The position of is adjusted vertically. When the position of the roller 19 reaches an appropriate position, the adjusting means 21 is fixed by the lock screw 22.
Do not rotate.

With the adjusting means as described above, the contact state of the hook with the hand and the pressing force can be adjusted to a desired value, and the hand can be securely fixed to the hand setting table. Next, a first device in which a hand installation table provided with such a hand holding device is floated from a satellite serving as a base and can be moved along the surface of the base will be described with reference to FIG.

8A and 8B show a first device in which the hand installation table is supported by parallel links, FIG. 8A is a plan view thereof, and FIG. 8B is its elevation view. Since the hand holding device has the same configuration as that shown in FIGS. 1 to 6, the same reference numerals are given and description thereof will be omitted. In addition, in FIG.
7, the conical guides 8 and 9, the cam 11 and the like are omitted.

The hand installation base 3 is connected to the base via a bearing 23 and a parallel link mechanism 24. The bearing 23 is for allowing the hand installation base 3 to freely rotate about a plane parallel to the plane of the base as a rotation surface. In other words, the bearing 23 is the hand installation base 3
Is rotatably supported within the plane of the hand setting table 3, and the parallel link mechanism 24 is
Is to be movable along a plane parallel to the base while maintaining its posture.

Further, the hand installation base 3 and the parallel link mechanism 2
4, a vine winding spring 25 having both ends fixed to the hand setting table 3 and the parallel link mechanism 24 is provided. The vine spring 25 is for holding the rotational position of the hand setting table 3 with respect to the base at the origin position.

Further, a returning means 26 for returning the hand setting table 3 to a predetermined plane origin position is provided on a part 3c of the hand setting table 3. It should be noted that the illustration of the returning means 26 is omitted in FIG.

FIG. 9 is an explanatory diagram of the restoring means 26.
That is, the cylindrical portion 26a is provided on the part 3c of the hand setting table 3 and the posts 26b to 26d (2
6d is not visible in FIG. 9) and three coil springs 26e to 26g (26g is not visible in FIG. 9) between the cylindrical portion 26a.
Are placed. The coil spring 26 is provided inside the cylindrical portion 26a.
h and a steel ball 26i are provided, and the steel ball 26i
A pedestal 26j is provided on the base as a receiving side. The cradle 26j includes a dent portion 26ja for positioning and a guide portion 2
6jb.

In the restoring means 26 having such a structure,
The part 3c of the hand installation base 3 includes three coil springs 26e.
It always tries to return to a position where the urging force of ~ 26g is balanced. Further, since the restoring force is weak near the equilibrium position, the recess 26ja of the pedestal 26j is arranged near the equilibrium position. As a result, the steel ball 26i falls into the recess 26ja by the urging force of the coil spring 26h, and the hand setting table 3 can be accurately returned to the predetermined plane origin position.
The guide portion 26jb is a part 3c of the hand setting table 3.
Is to prevent the coil springs 26e to 26g from significantly moving against the biasing force of the coil springs 26e to 26g.

Returning to FIG. 8, a part 3d of the hand setting table 3
In addition, blocking means 27 for blocking the planar movement of the hand setting table 3 is provided. In FIG. 8B, the blocking means 27
Are not shown.

FIG. 10 is an explanatory view of the blocking means 27. First, a pin hole 3da is provided in a part 3d of the hand setting table 3. A hook 27a having a pin inserted into the pin hole 3da is rotatably supported on the base. The pin has a conical shape to facilitate the detachment of the pin from the pin hole 3da. A roller 27b is attached to the hook 27a, and a cam 27c in contact with the roller 27b is provided on the base. The cam 27c uses a surface perpendicular to the rotation surface of the hook 27a as a rotation surface so that force transmission is irreversible and prevents the hook 27a once closed from opening due to vibration or the like. The cam 27c is driven by the cam drive motor 27d.

In the blocking means 27 having such a structure,
The rotation of the cam 27c causes the hook 27a to rotate in the direction of the arrow 28, whereby the pin provided on the hook 27a is inserted into or removed from the pin hole 3da of the part 3d of the hand installation base 3. When it is inserted, the plane movement of the hand setting table 3 is prevented, and the cam 27c and the hook 27a are
Due to the irreversible transmission of force between the hand installation base 3 and the satellite body with high rigidity,
The disengagement of the pin provided on the hook 27a can be reliably performed by forming the pin into a conical shape.

The operation of the first device configured as described above will be described below. First, the hand 2 is the hand setting table 3
When it is not mounted on the
The rotation position of the hand setting table 3 is returned and held at the origin position, and the returning means 26 returns and holds the hand setting table 3 at the predetermined plane origin position. By thus returning to the origin position, it is possible to prevent the accumulation of positional deviation when the hand 2 is coupled to the hand setting table 3 due to the bearing 23 and the parallel link mechanism 24, a so-called compliance mechanism. In addition, at the time of launching the satellite, the hand setting table 3 supported by the compliance mechanism is fixed by the blocking means 27, and after the launch, the blocking means 27 releases the fixing of the hand setting table 3.

Next, after the satellite is launched, the blocking means 27
When the hand 2 approaches the hand setting table 3 and comes into contact with the conical guides 8 to 10 provided on the hand setting table 3 after releasing the fixing of the hand setting table 3, the parallel link mechanism 24 is moved to the position of the hand 2. The hand setting table 3 is actuated following it, and the hand setting table 3 is moved along a plane parallel to the base table while maintaining its posture.
In addition, the rod-shaped guide pin 2a provided on the cylindrical side surface of the hand 2 has a V of the groove portion 10b provided on the conical guide 10a.
When in contact with the wall surface, the bearing 23 operates following the rotational position of the hand 2 to rotate the hand setting table 3 within the plane of the hand setting table 3.

Usually, a compliance mechanism is often provided on the wrist of the robot arm to give flexibility, but the movable range is ± several millimeters. On the other hand, there is an error of about ± 10 mm in the space robot arm that intentionally has rattling. However, by installing the parallel link mechanism 24 and the bearing 23 as described above, the tip position error of the robot arm can be sufficiently absorbed, and even a robot arm having a poor tip position accuracy can surely perform hand replacement, mounting, and the like. Further, by using the parallel link mechanism, the posture in the plane can be kept constant, and a relatively lightweight device can be obtained.

In the blocking means 27, the hook 27
An adjusting means having an eccentric shaft as shown in FIG. 7 is interposed between a and the rotating shaft of the roller 27b, and the distance between the two is adjusted by this adjusting means. As a result, it is possible to prevent the pins from coming off the pin holes due to variations in the dimensions of parts such as pins, pin holes, and cams, and the improper pressing force of the pins to the hand installation base. Can be securely fixed.

Next, a second device in which the hand setting table provided with the hand holding device is floated from the satellite serving as the base and can be moved along the surface of the base will be described with reference to FIG. To do.

FIG. 11 shows a second device in which the hand setting table is supported by a linear guide, and (A) is a plan view thereof.
(B) is an elevation view thereof. In addition, the hand holding device,
Since the configuration is the same as that shown in FIGS. 1 to 6, the same reference numerals are given and description thereof is omitted. Note that in FIG. 11B, the hooks 5 to 7, the conical guides 8 and 9, the cam 11 and the like are omitted.

The hand installation base 3 is connected to the base via a bearing 23 and a linear guide mechanism 29. The bearing 23 has the same structure as that shown in FIG. Further, the linear guide mechanism 29 is one in which two sets of linear guides are orthogonal to each other, and has the same function as the parallel link mechanism 24 shown in FIG. 8, and the hand installation table 3 is parallel to the base table. It moves along a flat plane while maintaining its posture.

As a result, the hand 2 approaches the hand setting table 3 and the conical guides 8 to 1 provided on the hand setting table 3 are provided.
When it comes into contact with 0, the linear guide mechanism 29 operates following the position of the hand 2 to move the hand setting table 3 while keeping its posture along a plane parallel to the base. Also,
A rod-shaped guide pin 2a provided on the cylindrical side surface of the hand 2
Bearing contacts the V-shaped wall surface of the groove portion 10b provided in the conical guide 10a, the bearing 23 operates following the rotational position of the hand 2 to move the hand setting table 3 to the hand setting table 3.
Rotate in the plane of.

Therefore, the tip position error of the robot arm can be sufficiently absorbed, and even a robot arm having a poor tip position accuracy can be replaced or mounted. Further, by using the linear guide mechanism, the posture in the plane can be kept constant, and a device having relatively high rigidity can be obtained.

Although not shown in FIG. 11, the second device is also provided with the vine spring 2 as in the first device.
5, a return means 26 and a blocking means 27 are provided, and the same operation is performed.

In the above embodiments, the hand holding device for the robot arm used in outer space has been described, but the present invention is applied to the hand holding device for the robot arm used in the ground FA system. You may

Further, in the above embodiment, the hand holding device 4
Although the part of the hand 2 that contacts with is made cylindrical, if this part is not cylindrical, the hand is provided with a cylindrical or disk-shaped guide.

[0048]

As described above, according to the present invention, by providing the hook for holding the hand and the cam for rotationally driving the hook, the hand can be securely held on the hand setting table side. Also, the robot arm tip can be fixed when the satellite is launched.

Further, by providing the parallel link mechanism or the linear guide mechanism, the bearing, the coil spring, and the returning means, the hands can be separated and attached smoothly.

Furthermore, by providing the blocking means, it is possible to provide a hand holding device that can withstand vibrations when the satellite is launched.

[Brief description of drawings]

FIG. 1 is a front view showing a schematic configuration of a space robot arm including a hand holding device.

FIG. 2 is a plan view of a hand installation table and a hand holding device.

FIG. 3 is an elevation view showing the structure of a hook.

FIG. 4 is a perspective view showing the structure of a conical guide.

5A and 5B are diagrams illustrating a cam, FIG. 5A is a plan view of the cam, FIG. 5B is an elevational view showing the relationship between the cam and the hook at the OA position in FIG. It is an elevation view which shows the relationship between a cam and a hook in the OB position of A).

FIG. 6 is an elevation view of the hand holding device.

7A and 7B are diagrams illustrating a hook capable of adjusting a rotational position and a pressing force, FIG. 7A is a perspective view of a hook including an adjusting unit and a roller, and FIG. 7B is a cross-sectional view thereof.

8A and 8B show a first device in which a hand installation base is supported by parallel links, FIG. 8A is a plan view thereof, and FIG. 8B is an elevation view thereof.

FIG. 9 is an explanatory diagram of a returning unit.

FIG. 10 is an explanatory diagram of blocking means.

[FIG. 11] Second hand support table supported by a linear guide
2A is a plan view thereof, and FIG. 3B is an elevation view thereof.

[Explanation of symbols]

 1 Robot Arm 2 Hand 3 Hand Installation Stand 4 Hand Holding Device 5 Hook 10 Conical Guide 11 Cam

Claims (16)

[Claims] 1. A hand holding device for holding a hand (2) connected to a tip of a robot arm (1) on a hand setting table (3), comprising a claw portion that comes into contact with the hand (2). A hook (5) rotatable around an axis fixed to the hand setting table (3) and a cam surface, and rotating by using a surface perpendicular to the rotation surface of the hook (5) as a rotation surface. A hand holding device comprising: a cam (11) for rotating the hook (5) by a cam surface. 2. A roller provided on the hook (5) and in contact with the cam surface of the cam (11) and a roller interposed between the hook (5) and the rotary shaft of the roller, and the distance between the two. The hand holding device according to claim 1, further comprising: an adjusting means having an eccentric shaft for adjusting. 3. A guide provided on the hand setting table (3) and having a tapered surface for positioning the hand (2) at a predetermined position of the hand setting table (3). The hand holding device according to claim 1. 4. A guide pin provided on the hand (2), and a V-shaped groove portion provided on the guide for engaging with the guide pin to position the rotational position of the hand (2). The hand holding device according to claim 3, further comprising: 5. The hand holding device according to claim 1, further comprising a parallel link provided on a base and supporting the hand installation base (3). 6. A return means for returning the hand installation base (3) to a predetermined plane origin position, comprising a plurality of coil springs provided between the base and the hand installation base (3). The hand holding device according to claim 5, further comprising: 7. A pin hole provided in the hand setting table (3), and an engagement means provided in the base and provided with a pin that engages with the pin hole. The hand holding device according to claim 5. 8. The engaging means rotates around a shaft fixed to the base as a center, and a hook surface rotatable about a surface perpendicular to the rotation surface of the hook portion as a rotation surface, and the engagement surface is rotated by a cam surface. A cam portion that rotates the hook portion, a roller portion that is provided on the hook portion and is in contact with the cam surface of the cam portion, and is interposed between the hook portion and the rotation shaft of the roller portion. 8. The hand holding device according to claim 7, further comprising an adjusting unit having an eccentric shaft for adjusting. 9. A bearing interposed between the parallel link and the hand installation table (3) for rotatably supporting the hand installation table (3) in a plane of the hand installation table (3). The hand holding device according to claim 5, further comprising: 10. A vine winding spring, which is interposed between the base and the hand installation base (3) and holds a rotational position of the hand installation base (3) with respect to the base at an origin position. The hand holding device according to claim 9, further comprising: 11. The hand holding device according to claim 1, further comprising a linear guide which is provided on a base and supports the hand installation base (3). 12. A return means for returning the hand installation table (3) to a predetermined plane origin position, comprising a plurality of coil springs provided between the base table and the hand installation table (3). Further comprising:
Hand holding device described. 13. A pin hole provided in the hand installation base, and an engagement means provided with a pin that is provided in the base and engages with the pin hole, further comprising: 11. The hand holding device according to item 11. 14. The engaging means is rotatable around a shaft fixed to the base, and a hook surface rotatable about a plane perpendicular to a rotation surface of the hook portion, and is rotated by a cam surface. A cam portion that rotates the hook portion, a roller portion that is provided on the hook portion and is in contact with the cam surface of the cam portion, and is interposed between the hook portion and the rotation shaft of the roller portion. 14. The hand holding device according to claim 13, further comprising an adjusting unit having an eccentric shaft for adjusting. 15. A bearing interposed between the linear guide and the hand installation table (3) for rotatably supporting the hand installation table (3) in a plane of the hand installation table (3). The hand holding device according to claim 11, further comprising: 16. A vine wound spring interposed between the base and the hand installation base (3) for holding a rotational position of the hand installation base (3) with respect to the base at an origin position, The hand holding device according to claim 14, further comprising: