Hand apparatus of a robot

Claim 1

A hand apparatus of a robot, comprising: a wrist; a main frame; damper coupling means resiliently mounting said main frame on said wrist member; a pair of four-point-articulated link arms each pivotally mounted on said main frame; a pair of sub-frames each pivotally mounted on said respective link arms; a pair of finger means each pivotally mounted for movement in every direction on said respective link arms; a pair of hydraulic cylinder means each including a cylinder and a piston rod and defining a head end chamber and a rod end chamber therein, said cylinder being pivotally connected to said main frame and said piston rod being pivotally connected to said respective link arms; and means for selectively supplying pressurized fluid to said head end and to said rod end chambers; said damper coupling means comprises: a plurality of damper couplings each comprising a cylindrical member having end walls fixedly secured on said wrist member, an internally concave spherical bushing slidable mounted within said cylindrical member, a partly spherical ring member rotatably received within said internally concave spherical bushing, a holder member mounted in said spherical ring member, said holder member having two flanges sandwiching said spherical ring member therebetween, a first and a second spring each mounted between one of the flanges and one of the end walls of said cylindrical member, and a rod inserted in said holder member, said rod having one end coupled to said holder member and the other end pivotally coupled to said main frame.