Gripping device

Abstract

A gripping device 10 for providing large moment-carrying capability for handling long cylindrical work-pieces W of a wide range of diameters. The device 10, which may be attached as an end effector for a robotic arm, includes two spaced pairs of parallel jaw type gripping members, 87, 102 and 101, 98. Each gripping member includes a gripping pad 110d with a contour which accommodates the grasping of cylindrical objects of different diameters. Movement of the gripping members between a fully open position (FIG. 3) and a fully closed position (FIG. 4) is controlled by a pair of concentrically arranged inner and outer output drive shafts 56, 59, each of which is provided with a pair of arms (81,82 and 83,84) extending in generally opposed radial directions of the shaft axis and to which a gripping member is pivotally attached near its distal end. The gripping device 10 includes a reversible motor 17 and transmission means 20 for simultaneously driving the pair of output drive shafts 56, 59 in counter-rotating directions relative to one another and for reversing their directions of rotation whereby the gripping member of each pair of gripping members may be moved to any position between their fully open and fully closed positions as desired. A mechanical linkage means such as members 81, 87, 89 and pivotally connected structure between pivots 91 and 92 is provided for each said gripping member for maintaining the gripping pads in parallel relationship throughout their range of movement.