Hand device, robot arm, and robot

1. A hand device comprising:

a hand base;

a first finger which extends from a front end portion of the hand base and which is fixed to the hand base so as to be immoveable relative to the hand base;

a second finger which is located behind the first finger and is attached to the hand base so as to face the first finger; and

a drive mechanism which actuates the second finger so that a tip portion of the second finger approaches or separates from the first finger, or approaches and separates from the first finger,

wherein

the drive mechanism comprises:

a drive source which generates a drive force to actuate the second finger; and

a brake provided between the drive source and the second finger,

the drive source generates the drive force in making an opened state where the tip portion of the second finger is separated from the first finger, and

the brake enables actuation of the second finger at a time of drive, and stops the actuation of the second finger at a time of non-drive.

2. The hand device according to claim 1 , wherein the tip portion of the second finger is located at a position closer to the hand base than a tip portion of the first finger in a closed state where the tip portion of the second finger is made to approach the first finger.

3. The hand device according to claim 1 , wherein the drive mechanism maintains a closed state where the tip portion of the second finger is made to approach the first finger at the time of non-drive.

4. The hand device according to claim 1 , wherein the drive mechanism rotates the second finger so that the tip portion of the second finger approaches or separates from the first finger, or approaches and separates from the first finger.

5. The hand device according to claim 1 , wherein the first finger is formed to be longer than the second finger in a direction perpendicular to a longitudinal direction of the hand base and to a direction in which the first finger extends, and has a projection at a position which faces the tip portion of the second finger, the projection projecting in a direction separating from the hand base.

6. The hand device according to claim 5 , wherein

the second finger has a nail which abuts the projection in a closed state where the tip portion of the second finger is made to approach the first finger, and

a length of the nail in the direction perpendicular to the longitudinal direction of the hand base and to the direction in which the first finger extends corresponds to a length of the projection of the first finger.

7. The hand device according to claim 1 , wherein the first finger has a buffer member on an opposite side of the second finger side.

8. A robot arm including:

a hand device;

a movable link; and

a joint mechanism which couples the movable link to the hand device, wherein

the hand device comprising:

a hand base;

a first finger which extends from a front end portion of the hand base and which is fixed to the hand base so as to be immoveable relative to the hand base;

a second finger which is located behind the first finger and is attached to the hand base so as to face the first finger; and

a drive mechanism which actuates the second finger so that a tip portion of the second finger approaches or separates from the first finger, or approaches and separates from the first finger,

wherein

the drive mechanism comprises:

a drive source which generates a drive force to actuate the second finger; and

a brake provided between the drive source and the second finger,

the drive source generates the drive force in making an opened state where the tip portion of the second finger is separated from the first finger,

the brake enables actuation of the second finger at a time of drive, and stops the actuation of the second finger at a time of non-drive, and

the joint mechanism couples the hand base of the hand device to the movable link rotatably on an opposite side of a side on which the first finger is extended.

9. A robot including:

a base body;

a plurality of movable links;

a plurality of joint mechanisms which rotatably couple the each movable link to the base body; and

a hand device coupled to at least one of the plurality of movable links, wherein

the hand device comprising:

a hand base;

a first finger which extends from a front end portion of the hand base and which is fixed to the hand base so as to be immoveable relative to the hand base;

a second finger which is located behind the first finger and is attached to the hand base so as to face the first finger; and

a drive mechanism which actuates the second finger so that a tip portion of the second finger approaches or separates from the first finger, or approaches and separates from the first finger,

wherein

the drive mechanism comprises:

a drive source which generates a drive force to actuate the second finger; and

a brake provided between the drive source and the second finger,

the drive source generates the drive force in making an opened state where the tip portion of the second finger is separated from the first finger, and

the brake enables actuation of the second finger at a time of drive, and stops the actuation of the second finger at a time of non-drive.

10. The robot according to claim 9 , wherein

the plurality of movable links each include: a pair of right and left arm links provided at upper parts of the base body; and a pair of right and left leg links provided at lower parts of the base body, and

the robot is switchable between a bipedal walking mode only by the leg links or the arm links and a quadrupedal walking mode by the leg links and the arm links.

11. The robot according to claim 9 , wherein

each of the movable links has a drive part which rotates the hand device with respect to the movable link, and

the drive part is located on the base body side of the movable link at a time of a reference posture in which the movable link is not rotated.