Clamping apparatus for machine tools

摘要

A clamping apparatus (3) for holding a workpiece (W) between an upper punching tool (19) and a lower punching tool (21) in a machine (1). A frame (33) attaches the clamping apparatus (3) to the machine (1). The clamping apparatus (3) comprises an upper clamp (61) and a lower clamp (57), the latter pivotably cooperating with the upper clamp (61) in order to secure the workpiece (W). The clamping apparatus (3) also comprises a plate member (51) and rods (49) and (75). These rods (49) and (75) are mounted in the frame (33) in a direction perpendicular to the workpiece (W). The lower end of the rods (49) and (75) are attached to the lower clamp (57) and the upper end of the rods (49) and (75) are attached to the plate member (51). A spring (83) is arranged between the lower clamp (57) and the plate member (51) for the purpose of maintaining the lower clamp (57) and the plate member (51) in horizontal orientation whenever the lower clamp (57) collides with the lower punching tool (21).