Patent ID: 7488020
Filing Date: 2009-02-10
Classification: B25J,Y10S

Abstract:
1. A workpiece-gripping chuck for gripping a workpiece by means of a pair of openable/closable gripping members, said workpiece-gripping chuck comprising: a body having a pair of ports to which a pressure fluid is supplied and cylinder chambers into which said pressure fluid is introduced; a driving section connected to said body which drives and rotates a pinion gear in accordance with an electrical signal; a pair of pistons displaceable in an axial direction in said cylinder chambers, wherein a driving force is transmitted to said pistons from said driving section via rack grooves meshed with said pinion gear, said rack grooves being formed on respective side surfaces of each of said pistons; a gripping section including said pair of gripping members connected to said pair of pistons, wherein said gripping members are openable/closable under a displacement action of said pistons; and a displacement amount-measuring mechanism which detects a displacement amount of said pistons in said axial direction, wherein said pistons are arranged oppositely to one another about a center of said pinion gear, and said pistons are displaced in said axial direction by applying said driving force from said driving section and/or a pressing force exerted by said pressure fluid.