Fluid amplifier-driven oscillator

Claim 1

IN A FLUID AMPLIFIER DRIVEN OSCILLATOR HAVING A PISTON ENCLOSED WITHIN A CYLINDER AND A ROD ATTACHED TO SAID PISTON AND EXTENDING EXTERNAL OF SAID CYLINDER AND BEING ACTED UPON BY THE PRESSURE OF THE STREAM OF FLUID SUPPLIED TO AN INPUT PORT IN SAID CYLINDER FROM AN OUTPUT CHANNEL OF A PURE FLUID BISTABLE AMPLIFIER TO PRODUCE RECIPROCATING MOVEMENT OF SAID PISTON, AND INCLUDING A FEEDBACK PATH FOR CONDUCTING A FLUID PRESSURE SIGNAL FROM A FEEDBACK PORT IN SAID CYLINDER TO A CONTROL NOZZLE OF SAID AMPLIFIER TO SWITCH THE POWER STREAM OF SAID AMPLIFIER INTO THE OTHER OUTPUT CHANNEL WHEN SAID PISTON HAS MOVED A PREDETERMINED DISTANCE, THE IMPROVEMENT COMPRISING: (A) CLOSURE MEANS SEPARATE FROM SAID PISTON AND HOUSED BY SAID CYLINDER FOR SELECTIVELY OPENING AND CLOSING SAID FEEDBACK PORT, (B) SAID CLOSURE MEANS BEING BIASED IN A CLOSED CONDITION TO PREVENT SPURIOUS FLUID SIGNALS FROM REACHING SAID CONTROL NOZZLE, AND (C) ACTUATING MEANS CARRIED BY SAID PISTON ROD COOPERATING WITH SAID CLOSURE MEANS TO OPEN SAID FEEDBACK PORT WHEN SAID PISTON HAS MOVED SAID PREDETERMINED DISTANCE.