Pressure and volume limiting ventilating apparatus

Claim 1

IN A VENTILATING APPARATUS HAVING AN INHALATION PHASE AND AN EXHALATION PHASE IN ITS OPERATIVE CYCLE, A CONTROLLER HAVING AN INLET ADAPTED TO BE CONNECTED TO A SOURCE OF GAS UNDER PRESSURE, SAID CONTROLLER HAVING AN OUTLET ADAPTED TO BE CONNECTED TO THE AIRWAY OF THE PATIENT, A MAIN CONTROL VALVE IN THE CONTROLLER MOVABLE BETWEEN OPEN AND CLOSED POSITIONS TO CONTROL THE FLOW OF GAS FROM THE INLET TO THE OUTLET, MEANS FOR OPERATING SAID MAIN CONTROL VALVE SO THAT THE MAIN CONTROL VALVE IS IN AN OPEN POSITION IN THE INHALATION PHASE AND IN A CLOSED POSITION IN THE EXHALATION PHASE OF THE VENTILATING APPARATUS, AND MEANS FOR SUPPLYING ADDITIONAL GASES TO THE OUTLET WHEN THE MAIN CONTROL VALVE DOES NOT SHIFT FROM AN OPEN POSITION TO A CLOSED POSITION WITHIN A PREDETERMINED PERIOD OF TIME, SAID LAST NAMED MEANS INCLUDING A FLUID SOURCE, ADJUSTABLE METERING MEANS FOR METERING THE FLOW OF FLUID FROM SAID FLUID SOURCE, AUTOMATIC FLOW ACCELERATOR VALVE MEANS CONNECTED TO SAID METERING MEANS AND ADAPTED TO RECEIVE FLUID FROM THE METERING MEANS, SAID FLOW ACCELERATOR VALVE MEANS INCLUDING A VALVE BODY HAVING A BORE THEREIN AND A VALVE MEMBER HAVNG AN ELONGATE STEM SLIDABLY DISPOSED IN THE BORE AND MOVABLE BETWEEN OPEN AND CLOSED POSITIONS WITH RESPECT TO THE BORE, AND MEANS CONNECTED TO SAID AUTOMATIC FLOW ACCELERATOR VALVE MEANS FOR SUPPLYING ADDITIONAL GAS TO THE OUTLET AS THE VALVE MEMBER IS MOVED TO AN OPEN POSITION.