초록 ▼

A fastener driving device of pneumatic type comprises a piston (20) within a cylinder (49), and a driver (21), connected to the piston (20) and movable through a fastener driving throat (26) formed by the housing of the device. A chamber (52) is provided within the housing to function as an air pres

A fastener driving device of pneumatic type comprises a piston (20) within a cylinder (49), and a driver (21), connected to the piston (20) and movable through a fastener driving throat (26) formed by the housing of the device. A chamber (52) is provided within the housing to function as an air pressure reservoir. First and second valves (15) provide an appreciably lower pressurized air to the underside of the piston (20). The valves (15) are so arranged that when they are in a first position they allow a flow of pressurized air from the reservoir (18) to the underside of the piston (20) and after the pressurized air under the piston (20) increases to a reduced predetermined ratio to that in the reservoir (18), the valves (15) shift to a second position blocking the flow. The valves (15) are capable of shifting to a third position allowing communication of the air pressure under the piston (20) with atmosphere while continuing to block communication with the reservoir.

대표청구항 ▼

A pneumatically powered fastener driving device comprising in combination a housing, a cylinder within said housing, a piston within said cylinder, a driver connected to said piston, a driving stroke means providing pressurized air to the upper side of said piston, a portion of said housing forming

A pneumatically powered fastener driving device comprising in combination a housing, a cylinder within said housing, a piston within said cylinder, a driver connected to said piston, a driving stroke means providing pressurized air to the upper side of said piston, a portion of said housing forming a driving throat through which said driver can move, means for inserting a fastener into said driving throat, a chamber within said housing to function as an air pressure reservoir, characterized in that it further comprises return stroke means providing an appreciably lower pressurized air to the underside of said piston, said return stroke means when in a first position allowing a flow of pressurized air from said reservoir to said underside of piston, after said pressurized air under said piston increases to a reduced predetermined ratio to that in said reservoir said return stroke means shifting to a second position blocking said flow, said return stroke means being capable of shifting to a third position allowing communication of said air pressure under the piston with atmosphere while continuing to block communication with said reservoir.