JP2013255958A - Robot hand and robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a robot hand transmitting driving force of a piezoelectric motor to a movable part by a transmitting shaft and operating, avoiding the generation of force inclining the transmitting shaft.SOLUTION: A robot hand is moved by transmitting the driving force of a piezoelectric motor to a movable part via a transmitting shaft. A supporting part pushing and pressing the transmitting shaft in a direction opposite to a direction in which the piezoelectric motor pushes the transmitting shaft is arranged in an opposite side of the piezoelectric motor to the transmitting shaft because the piezoelectric motor is used while being pushed to the transmitting shaft. Thus, force inclining the transmitting shaft is not generated because force by which the piezoelectric motor pushes and presses the transmitting shaft can be received by the supporting part. As a result, various kinds of problems are prevented from being generated by the transmitting shaft unevenly abutting on a member supporting the transmitting shaft.

Description

  The present invention relates to a robot hand and a robot.

A piezoelectric motor that drives a target object by vibrating a vibrating body including a piezoelectric material is known (for example, Patent Document 1). In addition, a robot hand equipped with a piezoelectric motor as a power source for opening and closing the finger has been proposed (Patent Document 2).

Since the robot hand has a large space restriction, it is often difficult to mount a power source such as a piezoelectric motor close to a member driven by the power source such as a finger. For this reason, it is normal to transmit the driving force generated by the power source to a member to be driven such as a finger portion via a transmission shaft.

JP 2008-187768 A JP 2008-1000031 A

However, since the piezoelectric motor is used by being pressed against the object to be driven, there is a problem that when the one end side of the transmission shaft is driven by the piezoelectric motor, a force that tilts the transmission shaft is generated. As a result, the transmission shaft easily contacts with the member supporting the transmission shaft, causing friction, shortening the service life, or rattling between the member supporting the transmission shaft and the transmission shaft. There was a bad effect such as that it is easy to generate sticking.

The present invention has been made to solve the above-described problems of the prior art,
In a robot hand using a piezoelectric motor as a power source, an object is to provide a technique capable of suppressing the generation of a force that tilts a transmission shaft that transmits a driving force from the piezoelectric motor to a movable portion.

In order to solve the above-described problems, the robot hand of the present invention employs the following configuration. That is,
A transmission shaft for transmitting a driving force to the movable part;
A piezoelectric motor that is pressed by the transmission shaft to drive the transmission shaft;
A support portion that is provided on the opposite side to the piezoelectric motor with respect to the transmission shaft, and that presses the transmission shaft in a direction opposite to the direction in which the piezoelectric motor presses the transmission shaft;
It is a summary to provide.

In the robot hand of the present invention having such a configuration, the movable portion connected to the transmission shaft is driven by driving the transmission shaft by the piezoelectric motor. In addition, the piezoelectric motor is provided in a state of being pressed against the transmission shaft, and on the side opposite to the piezoelectric motor with respect to the transmission shaft, the direction opposite to the direction in which the piezoelectric motor presses the transmission shaft. A support portion for pressing the transmission shaft is provided.

In this way, the force that the piezoelectric motor presses the transmission shaft can be supported by the support part,
It is possible to suppress the generation of a force for tilting the transmission shaft. As a result, the transmission shaft easily contacts with the member supporting the transmission shaft, causing friction, shortening the service life, or rattling between the member supporting the transmission shaft and the transmission shaft. It is possible to suppress adverse effects such as the occurrence of sticking.

In the above-described robot hand of the present invention, the piezoelectric motor may be provided in a state of being pressed against the transmission shaft from a direction orthogonal to the axial direction of the transmission shaft.

When driving the transmission shaft using a piezoelectric motor, driving the side surface of the transmission shaft from the direction orthogonal to the axial direction of the transmission shaft is more effective than driving the end surface of the transmission shaft. Since a long radius can be obtained, a large torque can be transmitted. However, when the side of the transmission shaft is driven, the force to tilt the transmission shaft also increases. However, if the transmission shaft is supported by the support from the opposite direction to the direction in which the piezoelectric motor presses the side of the transmission shaft, The force to tilt the shaft can be suppressed. For this reason, it is possible to transmit a large torque to the movable part of the robot hand without causing the harmful effect associated with the contact of the transmission shaft.

In the robot hand of the present invention described above, an elastic member that presses the transmission shaft may be provided in the support portion.

By doing so, when the force that the piezoelectric motor presses the transmission shaft becomes strong and the transmission shaft is inclined, the elastic member provided in the support portion is compressed, and the support portion presses the transmission shaft from the opposite side. Since the force also becomes strong, the inclination of the transmission shaft can be suppressed. Further, if the force with which the piezoelectric motor presses the transmission shaft becomes weak, the force with which the support portion presses the transmission shaft from the opposite side also becomes weak, so the transmission shaft does not tilt in the reverse direction.

In the robot hand of the present invention described above, the support portion may be configured by providing a piezoelectric motor on the opposite side of the transmission shaft from the piezoelectric motor. When the piezoelectric motor presses the end surface of the transmission shaft, the piezoelectric motor can be provided so as to press the end surface of the transmission shaft in the same direction from the position opposite to the piezoelectric motor with respect to the transmission shaft. That's fine. In addition, when the piezoelectric motor is pressing the side surface of the transmission shaft, the piezoelectric motor can be provided so as to press the end surface of the transmission shaft in the opposite direction from the position opposite to the piezoelectric motor with respect to the transmission shaft. That's fine.

In this way, the force with which one piezoelectric motor presses the transmission shaft can be canceled by the pressing force of the piezoelectric motor provided on the opposite side of the transmission shaft, so that the transmission shaft does not tilt. In addition, since the transmission shaft can be driven using two piezoelectric motors, a large driving force can be transmitted to the movable part of the robot hand.

Further, the above-described robot hand of the present invention may have the following configuration.
First, the robot hand is provided with two movable parts (a first movable part and a second movable part), a first drive shaft that transmits the driving force to the first movable part, and a first that transmits the driving force to the second movable part. 2 drive shafts are provided. Further, the second transmission shaft is incorporated inside the first transmission shaft. Then, the first transmission shaft may be driven by the first piezoelectric motor, and the second transmission shaft may be driven by the second piezoelectric motor.

In such a robot hand, since the first movable part and the second movable part can be driven by the first transmission shaft and the second transmission shaft incorporated inside the first transmission shaft, the robot hand can be reduced in size. Can be In addition, when the first transmission shaft and the second transmission shaft are incorporated coaxially, if any force that tilts the transmission shaft is applied to any of the transmission shafts, an adverse effect due to the contact is likely to occur. Since the force for tilting can be supported by the support portion, it is possible to reduce the size of the robot hand without causing any adverse effects associated with the contact.

In the robot hand of the present invention described above, the first piezoelectric motor and the second piezoelectric motor may be provided so as to overlap in the axial direction of the transmission shaft.

If the first piezoelectric motor and the second piezoelectric motor are overlapped in the axial direction of the transmission shaft, a region where the piezoelectric motor does not exist around the transmission shaft can be made wider than when the first piezoelectric motor and the second piezoelectric motor are not stacked. For this reason, since other components can be mounted in such a region, it is possible to reduce the size of the robot hand.

Alternatively, in the robot hand of the present invention described above, the first piezoelectric motor and the second piezoelectric motor may be provided at positions where the contours of the piezoelectric motor do not overlap when viewed from the axial direction of the transmission shaft.

When the contour of the first piezoelectric motor and the contour of the second piezoelectric motor overlap with each other when viewed from the axial direction of the transmission shaft, a portion where the surface of the first piezoelectric motor and the surface of the second piezoelectric motor face each other occurs,
In such a portion, it is difficult for either the first piezoelectric motor or the second piezoelectric motor to dissipate heat generated by driving. Therefore, if the contour of the first piezoelectric motor and the contour of the second piezoelectric motor are not overlapped when viewed from the axial direction of the transmission shaft, the heat generated by driving can be easily dissipated. It is possible to avoid the deterioration of the performance of the piezoelectric motor due to the above.

Further, the present invention described above can be grasped in the following manner. That is,
A robot equipped with a robot hand having a movable part,
The robot hand is
A transmission shaft for transmitting a driving force to the movable part;
A piezoelectric motor that is pressed by the transmission shaft to drive the transmission shaft;
A support portion that is provided on the opposite side to the piezoelectric motor with respect to the transmission shaft, and that presses the transmission shaft in a direction opposite to the direction in which the piezoelectric motor presses the transmission shaft;
It can also be grasped as a robot equipped with.

In such a robot of the present invention, the movable part of the robot hand is driven by the piezoelectric motor via the transmission shaft, so that the robot hand can be reduced in size. Moreover, since the force that the piezoelectric motor tries to tilt the transmission shaft can be supported by the support portion, it is possible to prevent the transmission shaft from tilting. As a result, it is possible to realize a robot that does not cause any adverse effects due to the tilt of the transmission shaft.

It is explanatory drawing which shows the structure of the robot hand of a present Example. It is explanatory drawing which shows operation | movement of the robot hand of a present Example. It is explanatory drawing which shows the structure of the transmission shaft unit of the robot hand of a present Example. It is explanatory drawing which showed operation | movement of the transmission shaft unit of a present Example. It is explanatory drawing which shows the structure of the transmission shaft unit and piezoelectric motor of the robot hand of a 1st modification. It is explanatory drawing which shows the structure of the transmission shaft unit and piezoelectric motor of the robot hand of a 2nd modification. It is explanatory drawing which illustrated the single arm robot provided with the robot hand. It is explanatory drawing which illustrated the robot of the multiple arms provided with the robot hand.

Hereinafter, in order to clarify the contents of the present invention described above, examples will be described in the following order.
A. The structure of the robot hand of this embodiment:
B. Holding operation of the robot hand of this embodiment:
C. Variations:
D. Application example:

A. The structure of the robot hand of this embodiment:
FIG. 1 is an explanatory diagram showing the structure of the robot hand 100 of the present embodiment. As shown in the figure, the robot hand 100 of this embodiment includes a plurality of blocks, a rack or a guide member for connecting the blocks, and the like. First, the configuration of the block will be described. In FIG. 1, the blocks are displayed with diagonal lines. The robot hand 100 of this embodiment is
Roughly speaking, four peripheral blocks 110B to 110E and four finger blocks 120, 130, and 140 are centered on a central block 110A provided on the base case 160.
, 150 are arranged around the central block 110A. Of these, the four peripheral blocks 110B to 110E are arranged to form a cross with the central block 110A as the center. The finger block 120 is disposed between the peripheral block 110B and the peripheral block 110C, and the finger block 130 is disposed between the peripheral block 110B and the peripheral block 110D. Similarly, the finger block 140 is connected to the peripheral block 11.
The finger block 150 is arranged between the 0C and the peripheral block 110E.
It is arranged between 0D and the peripheral block 110E. Also, finger blocks 120, 130
, 140, 150 are provided with finger members 122, 132, 142, 152, respectively. On the upper surface side of the central block 110A, a flat palm member 116 formed in a cross shape.
Is provided.

In addition, racks 114B to 114E are extended from the central block 110A in four directions, and the peripheral blocks 110B to 114E are provided at the tips of the racks 114B to 114E, respectively.
110E is attached. Of these, the racks (rack 114B and rack 114E, or rack 114C and rack 114D) connected to peripheral blocks at positions facing each other across the central block 110A are the bottom surfaces (base case 16) of the central block 110A.
The height from the attachment surface to 0) extends from the same position. In this embodiment, the rack 114B and the rack 114E are provided at higher positions than the rack 114C and the rack 114D. Each of the racks 114B to 114E has a gear tooth profile cut on one side of the side surface. The gears of these racks 114B to 114E are connected to a drive mechanism (not shown) provided inside the central block 110A. The drive mechanism will be described in detail later.

Each of the finger blocks 120, 130, 140, 150 is slidably attached to the peripheral blocks on both sides by two guide members. This will be specifically described below. First, a guide member 126a and a guide member 126b are erected on the finger block 120 in directions orthogonal to each other. Of these, the guide member 126a is a peripheral block 110.
The guide member 126b is slidably inserted into the guide hole 114 formed in the peripheral block 110C.

Similarly, for the finger block 130, the guide member 136a and the guide member 136b are erected in directions orthogonal to each other. The guide member 136a is a peripheral block 11.
The guide member 136b is slidably inserted into the guide hole 114 formed in the peripheral block 110B. Finger block 14
The same applies to 0 and the finger block 150. That is, from the finger block 140,
The guide member 146a and the guide member 146b are erected in directions orthogonal to each other,
The guide member 146a and the guide member 146b are slidably inserted through guide holes 114 formed in the peripheral block 110C and the peripheral block 110E, respectively. Similarly, a guide member 156a and a guide member 156b are erected from the finger block 150 in directions orthogonal to each other, and the guide member 156a and the guide member 156b are guides formed on the peripheral block 110E and the peripheral block 110D, respectively. The hole 114 is slidably inserted.

The inner diameters of the guide holes 114 provided in the peripheral blocks 110 </ b> B to 110 </ b> E are guide members 126 a, 126 b, 136 a, and 136 b that are fitted in the respective guide holes 114.
, 146a, 146b, 156a, 156b are set to sizes that can slide without rattling.

From the center of the upper surface of the central block 110A, a screw shaft 116 having a screw formed on the outer peripheral side surface.
a is erected, and a palm member 116 is attached to the tip of the screw shaft 116a. The screw shaft 116a is connected to a drive mechanism (not shown), which will be described later, in the central block 110A. Further, a guide shaft 116b is slidably provided on the upper surface of the central block 110A from the positions on both sides of the screw shaft 116a, and the tip of the guide shaft 116b is attached to the palm member 116.

The base case 160 is attached to the link portion 312 of the robot arm,
A piezoelectric motor (not shown) serving as a power source for a drive mechanism (not shown) is mounted inside the base case 160.

B. Holding operation of the robot hand of this embodiment:
FIG. 2 is an explanatory diagram illustrating an operation in which the robot hand 100 according to the present embodiment grips an object. When gripping an object, the size of the robot hand 100 in the width direction is changed according to the size of the object to be gripped. FIG. 2A shows how the size of the robot hand 100 in the width direction is changed. As described above with reference to FIG.
Guide members erected from 0, 130, 140, 150 are peripheral blocks 110B to 110.
The guide hole 114 of E is slidably inserted. Therefore, the peripheral block 110
If the distance between C and the peripheral block 110D is changed, the distance between the finger block 120 and the finger block 130 and the distance between the finger block 140 and the finger block 150 can be changed at the same time. Since the finger members 122, 132, 142, and 152 are attached to the upper surfaces of the finger blocks 120, 130, 140, and 150, when these finger blocks are moved, the finger members attached to the finger blocks are also moved. A mechanism for changing the interval between the peripheral block 110C and the peripheral block 110D will be described later. FIG. 2A illustrates a state where the interval is narrowed. In the robot hand 100 of this embodiment, FIG.
The direction in which the interval is narrowed in (a) is the “width direction”.

If the size in the width direction of the robot hand 100 is adjusted, the size in the holding direction of the robot hand 100 is reduced in accordance with the size of the object to be held. FIG.
b) shows how the size of the robot hand 100 in the holding direction is reduced.
The guide member erected from the finger blocks 120, 130, 140, 150 is the peripheral block 1
Since the guide holes 114 of 10B to 110E are slidably inserted, if the distance between the peripheral block 110B and the peripheral block 110E is narrowed, the distance between the finger block 120 and the finger block 140 is accordingly reduced. , And the interval between the finger block 130 and the finger block 150 can be simultaneously reduced. As a result, the distance between the finger member 122 and the finger member 142 and the distance between the finger member 132 and the finger member 152 can be simultaneously narrowed to hold the object. A mechanism for narrowing the distance between the peripheral block 110B and the peripheral block 110E will be described later. FIG. 2B illustrates how the interval is narrowed. In the robot hand 100 of this embodiment, the direction in which the interval is narrowed in FIG. 2B is the “gripping direction”.

Furthermore, in the robot hand 100 of the present embodiment, the palm member 116 is moved in the vertical direction,
The upper surface of the palm member 116 can be brought into contact with the object. In this way, the four finger members 12
2, 132, 152, 152 and the palm member 116 can be used to hold the object, so even a small object can be stably held. FIG. 2C shows the palm member 116.
A state in which the symbol is moved upward is shown.

Next, the width of the robot hand 100 and the size of the gripping direction are changed, or the palm member 116 is changed.
A mechanism for moving the frame up and down will be described.

FIG. 3 is an explanatory diagram showing the transmission shaft unit 200 mounted on the robot hand 100 of this embodiment. In FIG. 3, the transmission shaft unit 200,
Only the piezoelectric motor that drives the transmission shaft unit 200 is indicated by a solid line, and only a rough outline is indicated by a broken line.

The transmission shaft unit 200 of the present embodiment has a triple tube structure in which three transmission shafts are incorporated coaxially. A hollow circular tube-shaped first transmission shaft 212 is provided on the outermost transmission shaft of the transmission shaft unit 200, and a first pinion gear 206 is formed on the outer periphery of the upper end of the first transmission shaft 212. An annular flange 212 f is formed on the outer periphery of the lower end of the first transmission shaft 212.

On the inner side of the first transmission shaft 212, a hollow transmission pipe-shaped second transmission shaft 210 (not shown) (FIG. 4 (
b)) is housed rotatably with respect to the first transmission shaft 212. Second transmission shaft 21
0 is formed longer than the first transmission shaft 212, a second pinion gear 204 is formed on the outer periphery of the upper end of the second transmission shaft 210, and an annular flange 2 is formed on the outer periphery of the lower end of the second transmission shaft 210.
10f is formed. The first pinion gear 206 and the second pinion gear 204 are formed with the same outer diameter, and the flange 212f and the flange 210f are formed with the same outer diameter.

Further, inside the second transmission shaft 210, a third transmission shaft 208 (not shown) having a hollow circular tube shape (not shown).
4 (c)) is housed rotatably with respect to the second transmission shaft 210. The third transmission shaft 208 is formed to be longer than the second transmission shaft 210, and a screw portion 202 that is internally threaded is provided on the outer periphery of the upper end of the third transmission shaft 208. An annular flange 208 f is formed on the outer periphery of the lower end of the transmission shaft 208. The screw portion 202 is connected to the palm member 11.
The screw shaft 116 a connected to the screw 6 is screwed. Further, the flange 208f is a flange 2
The outer diameter is the same as 12f and flange 210f.

The upper half of the transmission shaft unit 200 having such a structure is housed in the central block 110 </ b> A, and the lower half of the transmission shaft unit 200 is housed in the base case 160. Further, in the base case 160, a first piezoelectric motor 162X for driving the first transmission shaft 212, a second piezoelectric motor 162Y for driving the second transmission shaft 210, and a third transmission shaft 208 are driven. A third piezoelectric motor 162Z is housed. Among these, the first piezoelectric motor 162X is pressed against the flange 212f of the first transmission shaft 212 from a direction orthogonal to the central axis 200L of the transmission shaft unit 200. Further, the second piezoelectric motor 162Y is from a direction orthogonal to the central axis 200L of the transmission shaft unit 200,
The third piezoelectric motor 162Z is pressed against the flange 210f of the second transmission shaft 210.
Is the third transmission shaft 20 from the direction orthogonal to the central axis 200L of the transmission shaft unit 200.
8 is pressed against the flange 208f.

Furthermore, in the robot hand 100 of the present embodiment, the first piezoelectric motor 163X is provided on the opposite side of the first transmission shaft 212 from the first piezoelectric motor 162X, and the first piezoelectric motor 163X is the first piezoelectric motor. From the side opposite to 162X, the flange 2 of the first transmission shaft 212
It is pressed against 12f. Similarly, for the second piezoelectric motor 162Y, a second piezoelectric motor 163Y is provided on the opposite side to the second transmission shaft 210, and the second piezoelectric motor 163Y has a second side from the side opposite to the second piezoelectric motor 162Y. 2 Flange 21 of transmission shaft 210
It is pressed to 0f. Further, the third transmission shaft 2 is also applied to the third piezoelectric motor 162Z.
A third piezoelectric motor 163Z is provided on the opposite side to 08, and the third piezoelectric motor 1
63Z is a flange 208 of the third transmission shaft 208 from the side opposite to the third piezoelectric motor 162Z.
It is pressed against f.

As described above, in the robot hand 100 of the present embodiment, the two first piezoelectric motors 162X and 163X that are paired are provided on the opposite side with the first transmission shaft 212 interposed therebetween. Similarly, the two second piezoelectric motors 162Y and 163Y that form a pair are provided on the opposite side across the second transmission shaft 210, and the two third piezoelectric motors 162Z and 163Z that form a pair serve as the third transmission shaft 20.
8 is provided on the opposite side. Therefore, when viewed from one of the two piezoelectric motors in a pair, the other piezoelectric motor corresponds to the “support portion” in the present invention.

FIG. 4 is an explanatory diagram showing the movement of the transmission shaft unit 200 when each piezoelectric motor is operated. FIG. 4A shows a case where the first piezoelectric motors 162X and 163X are operated. Note that, in order to avoid complication of illustration, in FIG. 4A, only the relevant part is represented by a thick solid line, and the other part is represented by a thin broken line.

As described above with reference to FIG. 3, the first piezoelectric motors 162 </ b> X and 163 </ b> X are connected to the first transmission shaft 2.
12 flanges 212f. Accordingly, the first piezoelectric motor 162X, 1
When 63X is operated, the first transmission shaft 212 rotates and the first pinion gear 206 formed at the upper end of the first transmission shaft 212 is rotated. The first pinion gear 206 is a rack 114C.
114D, the rack 114C is connected to the peripheral block 110C, and the rack 114D is connected to the peripheral block 110D. Therefore, when the first pinion gear 206 rotates, the movement of the first pinion gear 206 via the racks 114C and 114D is performed on the peripheral blocks 110C and 1C.
10D, the interval between the peripheral block 110C and the peripheral block 110D (interval in the width direction) is changed. For example, when the first pinion gear 206 is rotated clockwise in FIG. 4A, the distance between the peripheral block 110C and the peripheral block 110D is increased. Conversely, when the first pinion gear 206 is rotated counterclockwise, it moves in a direction in which the distance between the peripheral block 110C and the peripheral block 110D is reduced.

FIG. 4B shows a case where the second piezoelectric motors 162Y and 163Y are operated. In FIG. 4B as well, only the relevant part is represented by a thick solid line, and the other part is represented by a thin broken line. The second piezoelectric motors 162Y and 163Y are pressed against the flange 210f of the second transmission shaft 210. Accordingly, when the second piezoelectric motors 162Y and 163Y are operated, the second transmission shaft 210 rotates and the second pinion gear 204 formed at the upper end of the second transmission shaft 210 is rotated. The second pinion gear 204 has racks 114B and 114E.
The rack 114B is connected to the peripheral block 110B, and the rack 114E is connected to the peripheral block 110E. Therefore, when the second pinion gear 204 is rotated, the interval between the peripheral block 110B and the peripheral block 110E (interval in the gripping direction) is changed. For example, when the second pinion gear 204 is rotated clockwise in FIG. 4B, it moves in the direction in which the distance between the peripheral block 110B and the peripheral block 110E increases. Conversely, when the second pinion gear 204 is rotated counterclockwise, the peripheral block 110B and the peripheral block 1
It moves in the direction that the interval with 10E is narrowed.

FIG. 4C shows a case where the third piezoelectric motors 162Z and 163Z are operated. In FIG. 4C, only the relevant part is represented by a thick solid line, and the other part is represented by a thin broken line. The third piezoelectric motors 162Z and 163Z are pressed against the flange 208f of the third transmission shaft 208. Accordingly, when the third piezoelectric motors 162Z and 163Z are operated, the third transmission shaft 208 rotates, and the screw portion 202 formed at the upper end of the third transmission shaft 208 is rotated. The screw portion 202 is screwed with the screw shaft 116a, and the screw shaft 116a.
A palm member 116 is attached to the upper end of the. Further, a guide shaft 116b is erected from the upper surface of the central block 110A and attached to the palm member 116. For this reason, the palm member 116 can move up and down with respect to the central block 110A, but cannot rotate. Therefore, when the screw portion 202 is rotated, the screw shaft 116a screwed with the screw portion 202 moves in the vertical direction, and accordingly, the palm member 116 moves in the vertical direction. For example, in the example shown in FIG. 4C, when the screw portion 202 is rotated clockwise, the palm member 116 is rotated.
When the screw part 202 is rotated counterclockwise, the palm member 116 is moved.
Move in the direction of rising.

Thus, in the robot hand 100 of the present embodiment, when the flanges 212f, 210f, and 208f provided on the lower end side of the transmission shaft unit 200 are driven, the force is applied to the first pinion gear 206 on the upper end side of the transmission shaft unit 200. The second pinion gear 204 and the screw portion 202 are transmitted. Therefore, the first piezoelectric motors 162X, 163X, the second piezoelectric motors 162Y, 163Y, and the third piezoelectric motor 16 that drive the flanges 212f, 210f, 208f.
2Z and 163Z can be accommodated in the base case 160 on the lower end side of the transmission shaft unit 200. The transmission shaft unit 200 includes a first transmission shaft 212, a second transmission shaft 210, and a third transmission shaft.
Since the transmission shaft 208 has a triple tube structure in which the transmission shaft 208 is coaxially incorporated, the transmission shaft 208 can be very compact. Since the transmission shaft unit 200 is driven by a piezoelectric motor, the robot hand 100 can be made compact.

Here, as is well known, the piezoelectric motor is an object to be driven (here, the flange 2
12f, 210f, 208f). For this reason, the first transmission shaft 212,
A force that inclines the axes acts on the second transmission shaft 210 and the third transmission shaft 208. However, in this embodiment, a pair of piezoelectric motors (a first piezoelectric motor 162X and a first piezoelectric motor 163X, a second piezoelectric motor 162Y and a second piezoelectric motor) provided with the transmission shaft unit 200 interposed therebetween.
Since the piezoelectric motor 163Y, the third piezoelectric motor 162Z, and the third piezoelectric motor 163Z) are provided, the pressing forces of the paired piezoelectric motors cancel each other. Therefore, no force is applied to the first transmission shaft 212, the second transmission shaft 210, and the third transmission shaft 208 to incline the shaft. As a result, the first transmission shaft 212, the second transmission shaft 210, the third
It can be avoided that the transmission shaft 208 or the like is inclined inside the transmission shaft unit 200 to cause friction due to one-sided contact, occurrence of rattling or shortening of the service life.

Further, since each of the first transmission shaft 212, the second transmission shaft 210, and the third transmission shaft 208 can be driven by two piezoelectric motors, a large driving force can be generated, and the gripping force of the robot hand 100 can be generated. The gripping operation can be performed quickly.

Furthermore, in the robot hand 100 of the present embodiment, the first piezoelectric motor 162X, the second piezoelectric motor 162Y, and the third piezoelectric motor 162Z are provided in an overlapping manner. Similarly, the first piezoelectric motor 163X, the second piezoelectric motor 163Y, and the third piezoelectric motor 163Z are provided in an overlapping manner. For this reason, since six piezoelectric motors can be mounted in the base case 160 in two places, three by three, a large space for mounting other components in the base case 160 can be secured. . As a result, the robot hand 100 can be reduced in size.

C. Modified example:
There are several variations of the robot hand 100 of this embodiment described above. Hereinafter, these modified examples will be briefly described. In the following modification, the same components as those in the above-described embodiment are denoted by the same reference numerals as those in the above-described embodiment, and detailed description thereof is omitted.

C-1. First modification:
In the robot hand 100 of the embodiment described above, a pair of piezoelectric motors (first piezoelectric motor 162X and first piezoelectric motor 163X, second piezoelectric motor 162Y and second piezoelectric motor 163Y, third piezoelectric motor 162Z and third piezoelectric motor). 163Z) is provided on the opposite side across the transmission shaft (first transmission shaft 212, second transmission shaft 210, third transmission shaft 208), so that the pressing force of the piezoelectric motor is canceled by the piezoelectric motor on the opposite side As explained. However, it is sufficient if the pressing force of the piezoelectric motor can be supported from the opposite side, and it is not necessary to use a pair of piezoelectric motors.

For example, on the opposite side of the first piezoelectric motor 162X, the convex portion 16 that contacts the flange 212f.
4X may be provided so that the pressing force of the first piezoelectric motor 162X is supported by the convex portion 164X. Similarly, a convex portion 164Y is provided on the opposite side of the second piezoelectric motor 162Y, and a convex portion 164Z is provided on the opposite side of the third piezoelectric motor 162Z, so that the pressing force of the second piezoelectric motor 162Y or the third piezoelectric motor 162Z. May be supported by the convex portion 164Y or the convex portion 164Z. Furthermore, as shown in FIG. 5, an elastic member 16 such as a coil spring.
The convex portions 164X to 164Z may be urged to the flanges 212f to 208f using 5X to 165Z.

C-2. Second modification:
In the robot hand 100 of the present embodiment described above, the first to third piezoelectric motors (the first piezoelectric motor 162X and the second piezoelectric motor 162Y and the third piezoelectric motor 162Z, or the first piezoelectric motor 163X and the second piezoelectric motor). Motor 163Y and third piezoelectric motor 163Z
) Is provided so as to overlap with the axial direction of the transmission shaft unit 200. However, the first to third piezoelectric motors may be provided at positions that do not overlap with the axial direction of the transmission shaft unit 200.

FIG. 6 is an explanatory view illustrating the robot hand 100 of the second modified example. As shown in the drawing, in the robot hand 100 of the second modification, the first piezoelectric motor 162X, the second piezoelectric motor 162Y, and the third piezoelectric motor 162Z are provided at positions that do not overlap with each other.
The piezoelectric motor 163X, the second piezoelectric motor 163Y, and the third piezoelectric motor 163Z are provided at positions that do not overlap. In this way, a sufficient gap can be secured around any piezoelectric motor. For this reason, since the cooling performance of the piezoelectric motor is improved, the performance does not deteriorate due to heat.

D. Application example:
The robot hand 100 of this embodiment and the modification described above can be applied to the following robots.

FIG. 7 is an explanatory view illustrating a single-arm robot 300 including the robot hand 100. As illustrated, the robot 350 includes a plurality of link units 312 and the link units 31.
It has the arm 310 provided with the joint part 320 which connects between two in the state which can be bent.
The robot hand 100 is connected to the tip of the arm 310. For this reason, it is possible to grip the target by driving the arm 310 to bring the robot hand 100 close to the position of the target and driving the finger members 122, 132, 142, 152 of the robot hand 100 in this state. Is possible.

FIG. 8 is an explanatory view illustrating a multi-arm robot 350 including the robot hand 100. As illustrated, the robot 350 includes a plurality of link units 312 and the link units 31.
There are a plurality of arms 310 (two in the illustrated example) provided with joint portions 320 that connect the two in a bendable state. A robot hand 100 and a tool 301 are connected to the tip of the arm 310. In addition, a plurality of cameras 353 are mounted on the head 352, and a control unit 356 that controls the overall operation is mounted inside the main body 354. Further, it can be conveyed by a caster 358 provided on the bottom surface of the main body 354. This robot 35
In addition, the robot 310 is driven to the position of the object by driving the arm 310, and the finger member 122, 132, 142, 152 of the robot hand 100 is driven in this state to hold the object. Is possible.

As described above, the robot hand and the robot according to various embodiments have been described. However, the present invention is not limited to all the embodiments and modifications described above, and can be implemented in various modes without departing from the gist thereof. is there.

100 ... Robot hand, 110A ... Central block,
110B to E ... peripheral block, 114 ... guide hole, 114B to E ... rack,
116 ... Palm member, 116a ... Screw shaft, 116b ... Guide shaft,
120 ... finger block, 122 ... finger member, 126a, b ... guide member,
130 ... finger block, 132 ... finger member, 136a, b ... guide member,
140 ... finger block, 142 ... finger member, 146a, b ... guide member,
150 ... finger block, 152 ... finger member, 156a, b ... guide member,
160: base case, 162X: first piezoelectric motor,
162Y: second piezoelectric motor, 162Z: third piezoelectric motor,
163X: first piezoelectric motor, 163Y: second piezoelectric motor,
163Z ... third piezoelectric motor, 164X to Z ... convex portion,
165X to Z ... elastic member, 200 ... transmission shaft unit, 202 ... screw part,
204 ... 2nd pinion gear, 206 ... 1st pinion gear,
208 ... third transmission shaft, 208f ... flange, 210 ... second transmission shaft,
210f ... flange, 212 ... first transmission shaft, 212f ... flange,
300 ... Robot, 301 ... Tool, 310 ... Arm,
312 ... Link part, 320 ... Joint part, 350 ... Robot,
352 ... head, 353 ... camera, 354 ... main body,
356 ... Control unit, 358 ... Caster

Claims (8)

A transmission shaft for transmitting a driving force to the movable part;
A piezoelectric motor that is pressed by the transmission shaft to drive the transmission shaft;
A support portion that is provided on the opposite side to the piezoelectric motor with respect to the transmission shaft, and that presses the transmission shaft in a direction opposite to the direction in which the piezoelectric motor presses the transmission shaft;
Robot hand equipped with. The robot hand according to claim 1,
The robot hand, wherein the piezoelectric motor is pressed from a direction orthogonal to the axial direction of the transmission shaft. The robot hand according to claim 1 or 2,
The robot hand according to claim 1, wherein the support portion includes an elastic member that presses the transmission shaft. The robot hand according to claim 1 or 2,
The robot hand according to claim 1, wherein the support portion is the piezoelectric motor provided on the opposite side to the piezoelectric motor with respect to the transmission shaft. A robot hand according to any one of claims 1 to 4,
The movable part includes a first movable part and a second movable part,
The transmission shaft includes a first transmission shaft that transmits a driving force to the first movable portion, and a second transmission shaft that is incorporated inside the first transmission shaft and transmits the driving force to the second movable portion. Has
The robot hand includes: a first piezoelectric motor that drives the first transmission shaft; and a second piezoelectric motor that drives the second transmission shaft. The robot hand according to claim 5,
The robot hand, wherein the first piezoelectric motor and the second piezoelectric motor are provided so as to overlap each other in the axial direction of the transmission shaft. The robot hand according to claim 5,
The robot hand, wherein the first piezoelectric motor and the second piezoelectric motor are provided at positions where the contours of the piezoelectric motor do not overlap when viewed in the axial direction of the transmission shaft. A robot equipped with a robot hand having a movable part,
The robot hand is
A transmission shaft for transmitting a driving force to the movable part;
A piezoelectric motor that is pressed by the transmission shaft to drive the transmission shaft;
A support portion that is provided on the opposite side to the piezoelectric motor with respect to the transmission shaft, and that presses the transmission shaft in a direction opposite to the direction in which the piezoelectric motor presses the transmission shaft;
Robot equipped with.

Images