Proportional pilot-controlled pneumatic control system for pneumatically powered hand-held tools

A system for powering and controlling a piston-actuated power tool having a piston, the system comprising:

• a primary power system including a first supply line in fluid communication with the tool, the primary power system operable to provide pressurized air to the tool so as to actuate the piston based upon a rate of exhausted pressurized air from the primary power system;
• and
• a control system for providing pressurized air to the tool so as to control the tool, the control system including—
• an exhaust line in fluid communication with the primary power system and the control system so as to supply the exhausted pressurized air from the primary power system and to the control system,
• a second supply line in fluid communication with a pressurized air source and the control system for supplying pressurized air to the control system,
• a spool valve in fluid communication with the exhaust line and the second supply line and including a metering slot,
• wherein the pressurized air from the pressurized air source is supplied to the spool valve via the second supply line, and
• wherein exhausted pressurized air from the primary power system is supplied to the spool valve via the exhaust line and exhausted out of the metering slot, and
• a control line in fluid communication with the second supply line and the power tool,
• wherein pressurized air supplied by the second supply line and to the spool valve is expelled from the spool valve via the control line by a user selectively expelling the pressurized air from the power tool, and
• wherein the selective expulsion of the pressurized air from the spool valve directly affects the amount of exhausted pressurized air exhausted from the metering slot of the spool valve.