Pneumatic fastener driving tool and an electronic control system therefor

An electronically controlled pneumatic fastener driving tool. The tool is of the type having a body containing a cylinder with a piston/driver assembly therein, a firing valve actuable to introduce high pressure air into the cylinder to cycle the piston/driver assembly, a manual trigger, a safety trip, and an electronic control system. The electronic control system comprises a remote solenoid valve to actuate the firing valve, a microprocessor having inputs from at least the trigger and safety trip and an output to energize the solenoid of the remote valve to cycle the tool, a battery to energize the microprocessor and a rechargeable battery to energize the solenoid of the remote valve. The microprocessor determines the mode of operation of the tool and may be designed to provide two or more modes selectable by a mode selection switch. The input from the trigger is provided with a reed switch closable by the trigger and the input from the safety trip is provided with a reed switch closable by the safety trip. The microprocessor may provide a timer to impose a time limit on the trigger, the safety trip, or both. The electronic control system comprises a part of the tool itself. The tool is provided with a generator which partially recharges the solenoid battery during each cycle of the tool.