Abstract: A driving tool includes a chamber to store compressed air and a relief valve in communication with the chamber. The relief valve includes an inflow channel communicating with the chamber and an outflow channel with a larger diameter formed at a downstream side of the inflow channel. A valve stem moves along the inflow channel. An O-ring to seal the inflow channel is attached in an annular groove of the valve stem. Air release channels are defined in the valve stem. Each air release channel includes an inlet that opens to an inner circumferential chamber and an outlet that opens to the outflow channel to allow the compressed air to be discharged from the inner circumferential chamber to the outflow channel when the O-ring moves toward the outflow channel and moves beyond the inflow channel due to the internal pressure of the chamber.

Abstract: A driving tool includes a chamber to store compressed air and a relief valve in communication with the chamber. The relief valve includes an inflow channel communicating with the chamber and an outflow channel with a larger diameter formed at a downstream side of the inflow channel. A valve stem moves along the inflow channel. An O-ring to seal the inflow channel is attached in an annular groove of the valve stem. Air release channels are defined in the valve stem. Each air release channel includes an inlet that opens to an inner circumferential chamber and an outlet that opens to the outflow channel to allow the compressed air to be discharged from the inner circumferential chamber to the outflow channel when the O-ring moves toward the outflow channel and moves beyond the inflow channel due to the internal pressure of the chamber.

Abstract: A magazine in a fastener driving tool includes a magazine body, a pusher, a biasing device and a pusher holding device. The magazine body defines a fastener receiving space for storing a plurality of fasteners therein. The pusher is mounted to the magazine body and is movable in a fastener feeding direction toward a fastener driving channel defined in a tool body of the fastener driving tool. The biasing device biases the pusher in the fastener feeding direction. The pusher holding device can hold the pusher at a midway position within a movable range of the pusher in the fastener feeding direction. The pusher holding device may include no insertion hole or only one insertion hole formed in the magazine body.

Abstract: A magazine in a fastener driving tool includes a magazine body, a pusher, a biasing device and a pusher holding device. The magazine body defines a fastener receiving space for storing a plurality of fasteners therein. The pusher is mounted to the magazine body and is movable in a fattener feeding direction toward a fastener driving channel defined in a tool body of the fastener driving tool. The biasing device biases the pusher in the fastener feeding direction. The pusher holding device can hold the pusher at a midway position within a movable range of the pusher in the fastener feeding direction. The pusher holding device may include no insertion hole or only one insertion hole formed in the magazine body.

Abstract: When a screw 14 is driven into workpieces 61 and 62, it is possible to reduce any reaction that a driver bit 11 is raised so as to obtain fast and reliable screw driving. In the screw driving method of the present invention, the screw is advanced with a strong pressing force of 7-10 Kg during a period from disengagement step of the screw from a carrier strip 14 to driving step of the tip of the screw to the predetermined depth (the lower surface) of the workpiece 61. When the screw is screwed into the workpiece 62, the driver bit 11 is advanced with a weak pressing force of 2-3 Kg. In a screw driving apparatus of the present invention, the fitted screw is disengaged from a screw carrier strip by means of a forward stroke force of the driver bit. The tip of the screw is driven to a predetermined depth in a workpiece. During the term between the disengagement and the driving of the screw, the driver bit is advised with a strong pressing force by a primary piston 26.