Abstract: A vibrating cutting tool having an input shaft driven by a live spindle of a machine tool and an output shaft having a cutter mounting portion. The input shaft and the output shaft are coupled together through a coupling mechanism so as to be at least circumferentially movable relative to each other. Recesses are formed in one of the input shaft and the output shaft and holes are formed in the other at locations opposite to the recesses. Moving elements are mounted between the recesses and the holes with a predetermined gap defined between the moving elements and the recesses or the peripheral surfaces of the holes. The gaps serve to restrict a circumferential movement of the moving elements. Springs are provided to urge the moving elements against the recesses. The movement of the moving elements is restricted by stoppers. An adjusting ring may be provided to adjust the biasing force of the springs.

Abstract: The present invention relates to improvements in a hydropneumatic gun for setting blind-rivet nuts used for integrally securing, for example, two panels to each other with a nut. In the hydropneumatic gun for setting blind-rivet nuts, an air piston fitted in air cylinder is moved to pressurize oil housed in the gun body, causing an oil piston to be retracted, so that a screw mandrel attached to the oil piston at its tip is retracted to the inner part of the gun body, thereby to exert a deforming force to a sleeve of a nut threadedly mounted on the screw mandrel. The hydropneumatic gun for setting blind-rivet nuts comprises an air motor to be rotated by compressed air, an air motor driving air guide passage, an air motor forward/reverse rotation direction changeover mechanism for switching the rotation direction of the air motor, and a power transmission mechanism for transmitting an air motor driving force to the screw mandrel.