| 摘要 |
<p>A fluid-operated actuator (10) for collets, vises, chucks and other workpiece engagement devices, for example, the actuator (10) having a piston (22) which moves the engagement device (14) toward the workpiece (16) with a force equal to product of the area of the face (32) of the piston (22) times the pressure of a fluid applied to the face. When the engagement device (14) has engaged the workpiece (16), additional, relatively slight movement of the piston causes a force multiplying mechanism (42-50) to provide increased engagement force without increasing the pressure of the actuating fluid. The overall travel of the actuator mechanism is not limited by the force-multiplying mechanism which begins to function only after the unrelated distance of travel of the engagement device to the workpiece. Thus, for example, compressed air at ordinary shop pressures may be used to actuate collets or chucks on automatic lathes or the like to provide relatively high clamping forces.</p> |
