Robot hand for forging working

A robot arm for gripping a workpiece, comprising:

• (a) a robot hand including:
• (i) a grip hand for gripping the workpiece;
• and
• (ii) a grip hand support for supporting said grip hand;
• said grip hand including a plurality of fingers for gripping the workpiece, and a grip body having two end portions, one end portion having said fingers movably mounted thereon;
• said grip hand support having a longitudinal axis and including a casing into which the other end portion of said grip body is inserted;
• support means disposed in said casing for supporting said other end portion of said grip body so that said grip hand is movable relative to said casing in any desired direction in an imaginary plane passing through said casing and perpendicular to said longitudinal axis, inclinable relative to said casing in a desired direction in a three-dimensional space around a point on the imaginary plane and midway through said casing, and slidable relative to said casing in an axial direction of said grip hand;
• and supporting state changing means for changing the state of said grip hand support between a displacement changing state, in which said grip hand is movable, inclinable, and slidable relative to said casing when an external force is applied to said grip hand as said grip hand is gripping the workpiece, a constraining state in which said grip hand is constrained to inhibit the movement, inclination, and sliding thereof unless an external force greater than a predetermined force is applied to said grip hand, and an initial neutral position constraining state in which said grip hand is positioned at a predetermined initial neutral position and is constrained to inhibit the movement, inclination, and sliding thereof to make movement, inclination, and sliding of said grip hand impossible;
• and
• (b) a robot hand support for rotating said robot hand around the longitudinal axis of said grip hand support to rotate said grip hand.

A robot hand for gripping a workpiece to be forged, comprising:

• a grip for gripping the workpiece;
• and
• a grip support for supporting said grip so that said grip is movable in directions parallel with and rotatable around three independent axes which are perpendicular to each other in a three-dimensional space and so can be moved in a resultant direction;
• said grip including a plurality of fingers for gripping the workpiece, and a grip body having two end portions, one end portion having said fingers movably mounted thereon;
• said grip support including a casing into which the other end portion of said grip body is inserted;
• support means disposed in said casing for supporting said other end portion of said grip body so that said grip is movable and rotatable relative to said casing;
• and
• supporting state changing means for changing the supporting state of said grip support between a displacement enabling state, in which said grip is movable and/or rotatable relative to said casing when an external force is applied to said grip as said grip is gripping the workpiece, a constraining state, in which said grip is constrained to inhibit the movement and rotation thereof unless an external force greater than a predetermined force is applied to said grip, and an initial position constraining state in which said grip is positioned at a predetermined initial position relative to said casing and is constrained in said initial position to prevent movement and rotation thereof.