Pneumatic tool

Claim 1

A PNEUMATIC TOOL COMPRISING A SLENDER ELONGATED HOUSING, A CHAMBER IN EACH END OF SAID HOUSING, A PISTON INTIMATELY RECIPROCATING IN SAID HOUSING, A TOOL BIT HOLDER INTEGRAL WITH SAID PISTON, SAID HOLDER AND SAID PISTON BEING LONGITUDINALLY DISPOSED WITH RESPECT TO THE LONGITUDINAL AXIS OF SAID HOUSING, SAID PISTON BEING OF RELATIVELY SMALL MASS AND SMALL INERTIA WITH RESPECT TO SAID HOUSING, SAID HOUSING HAVING AN APERTURE IN ONE END WHEREBY THE RECIPROCAL MOTION OF SAID PISTON IN SAID HOUSING MAY BE TRANSMITTED TO SAID TOOL BIT HOLDER TO PROVIDE AN OPERATING FORCE OUTSIDE OF SAID HOUSING, A FLUID OUTLET AT THE OTHER END OF SAID HOUSING, CHANNEL MEANS IN SAID HOUSING AND IN SAID PISTON FOR ALTERNATELY DIRECTING FLUID FROM SAID INLET TO EACH OTHER OF SAID CHAMBERS TO DRIVE SAID PISTON IN A FORWARD STROKE AND IN A RETURN STROKE, SAID CHANNEL MEANS COMPRISING A DRIVE PASSAGE COMMUNICATING WITH SAID FLUID INLET AND HAVING A PAIR OF BRANCHES TERMINATING ADJACENT SAID PISTON, A FORWARD STROKE PASSAGE COMMUNICATING WITH ONE OF SAID CHAMBERS AND TERMINATING ADJACENT SAID PISTON, A RETURN STROKE PASSAGE COMMUNICATING WITH THE OTHER OF SAID CHAMBERS AND TERMINATING ADJACENT SAID PISTON, AND GROOVE MEANS IN SAID PISTON WHEREBY MOVEMENT OF SAID PISTON CAUSES SAID GROOVE MEANS TO OPEN AND CLOSE COMMUNICATION OF SAID DRIVE PASSAGE WITH SAID FORWARD STROKE PASSAGE AND SAID RETURN STROKE PASSAGE TO PERMIT SAID FLUID TO ALTERNATELY FLOW TO EACH OF SAID CHAMBERS.