Patent ID: 6152659
Filing Date: 2000-11-28
Classification: B23G,Y10T

Abstract:
A rotary driving device for a press machine, which is supported by a supporting member and driven by a striker for rotating and extending a tool into a workpiece, the rotary driving device comprising:a main body including an upper member and a lower member, the main body being supported movably in an axial direction thereof by the supporting member;a push head member provided on the upper member of the main body, the push head member being movable in the axial direction of the striker;urging means mounted inside the upper member of the main body, for generating a return elastic force to urge the push head member in a direction opposite a striking direction of the striker;a male thread axle member supported rotatably by the push head member, the male thread axle member having a male thread;a female thread supported by the upper member of the main body, the female thread being movable in an axial direction and immovable in a circumferential direction relative to the upper member, and the female thread being in mesh with the male thread;a lead nut exchangeably and fixedly mounted on the lower member of the main body;a lead thread member in mesh with the lead nut and rotatably supported by the main body, for holding a rotary driven tool;coupling means for coupling the male thread axle member and the lead thread member in torque transmission relationship and in relative axial displacement relationship with respect to each other so as to absorb a difference in axial speeds between the male thread axle member and the lead thread member; andfirst impact absorbing means interposed between a lower surface of the female thread and an upper surface of the lower member.