ES375864A1 - Fluid pressure operated fastener driving device - Google Patents

Abstract

A fastener driving device, comprising: a box having means defining a pressure reservoir for receiving and containing pressurized fluid, supplied thereto from a pressurized fluid source; means defining a driving track for receiving successive fasteners to be driven, from a supply of fasteners fed thereto; fastener driving means, supported by said box, for movement from a fastener receiving position, through said driving track, in a driving stroke, to a driven fastener position, and from said driven fastener position, to through a return stroke, to said bras receiving position; means within said box, which define a driving pressure chamber, arranged in fluid communication relationship with said fastening driving means; main control valve means, movable between a first position that communicates said driving chamber with the atmosphere and that closes the communication between said driving chamber and said tank, and a second position that communicates said driving chamber with said tank and which closes the communication of said driving chamber with the atmosphere, so that said fastener driving means is moved through said driving stroke, in response to the movement of said main valve means, to said second position and through said return stroke, in response to movement of said main valve means, to said first position; means defining a pilot pressure chamber; a pilot pressure actuated member arranged in pressure communication relationship with said pilot chamber for movement between a first position, in response to pilot pressure communication within said pilot chamber, and a second position in response to leakage from said pilot chamber to the atmosphere; means operable, in response to movement of said pilot pressure actuated member to said first position, to effect movement of said main valve means to said second position, and operable, in response to movement of said pilot pressure actuated member to said first position second position, to effect movement of said main valve means to said first position; means defining a restricted orifice, which continuously communicates said tank with said pilot chamber; means defining an exhaust outlet for said pilot chamber, of a size greater than said restricted orifice; manually operable valve means, mounted for movement between a normally closed position that prevents communication of said pilot pressure chamber with said exhaust outlet, and an open, manually operated position, which communicates said pilot chamber with said exhaust outlet; self-firing valve means, arranged in series with said manually operable valve means, between said pilot chamber and said exhaust outlet, to control communication of said pilot chamber and said exhaust outlet when said manually operable valve means are arranged in said manually operated open position; said self-firing valve means including a valve member mounted for movement between an open position, which communicates said pilot pressure chamber with said exhaust outlet, when said manually operated valve means are arranged in said manually operated open position, and a closed position that prevents communication of said pilot chamber with said exhaust outlet when said manually operated valve means are arranged in said manually operated open position; first pressure surface means, functionally associated with said valve member and arranged in pressure communication relationship with said pilot chamber, operable to load said valve member to said open position, in response to pressure communication in said pilot chamber with the same; second pressure surface means functionally associated with said valve member, of an effective area sufficiently greater than the effective area of said first pressure surface means, to load said valve member to said closed position, in response to communication of signal pressure therewith, with a force greater than the force acting on said first pressure surface means loading said valve member to said open position; and means for communicating with said second pressure surface means a signal pressure, separate from said pilot pressure, established as a consequence of movement of said pilot pressure actuated member to said second position, the signal pressure of which is dissipated as a consequence of movement of said pilot pressure actuated member to said first position, such that when said manually operable valve means are disposed in said manually operated open position, said self-firing valve means is operable to effect movement of said driving means fasteners through continuous driving and return stroke cycles, until said manually operable valve means is moved to said closed position. (Machine-translation by Google Translate, not legally binding)