Patent ID: 7490748
Filing Date: 2009-02-17
Classification: B25C

Abstract:
1. A pneumatically operated fastener driving tool comprising: a housing having a top wall region provided with a shaft; a cylinder disposed within the housing; a piston reciprocally slidably disposed within the cylinder, the piston being movable between its top dead center and a bottom dead center; a head bumper against which the piston bumps when the piston is moved toward its top dead center, the head bumper being made from an elastic material and having a fitting portion elastically fitted over the shaft and a contacting portion integral with the fitting portion and having one end surface in contact with the top wall region and having an outer peripheral surface; and a sleeve valve movable in a moving direction of the piston between a first position and a second position, the sleeve valve having an inner peripheral surface part in contact with the outer peripheral surface of the contacting portion and has one axial end in contact with the top wall region when the sleeve valve is positioned at the first position; wherein the contacting portion being deflectable when the inner peripheral surface part is slidingly moved from the first position toward the second position with respect to the outer peripheral surface of the contacting portion; wherein a discharge port is formed to allow a compressed fluid entered between the top wall region and the contacting portion to be discharged to an atmosphere.