Internal combustion engine

Claim 1

IN AN INTERNAL COMBUSTION ENGINE HAVING A COMBUSTION CHAMBER SUPPLIED BY AN INTAKE MANIFOLD MEANS, AND A CRANKSHAFT HOUSED BY A CRANKCASE AND ROTATED BY A RECIPROCATING PISTON AND CONNECTING ROD MEANS, THE COMBINATION OF CRANKCASE FUME UTILIZATION MEANS COMPRISING MEANS EFFECTIVE TO PREVENT THE EMISSION TO ATMOSPHERE OF CRANKCASE FUMES AND TO SEAL SAID CRANKCASE AGAINST THE ENTRANCE OF AIR OR AIRBORNE MATTER THEREINTO, A NORMALLY CLOSED, PRESSURE RESPONSIVE VALVE MEANS DISPOSED IN COMMUNICATION WITH THE INTERIOR OF SAID CRANKCASE AND BIASED TO OPEN ONLY IN THE EVENT THAT PRESSURE WITHIN THE CRANKCASE EXCEEDS BY A PREDETERMINED MAGNITUDE THE ATMOSPHERIC PRESSURE AT THE ALTITUDE AT WHICH THE ENGINE IS SITUATED, CONDUIT MEANS CONNECTING THE INTERIOR OF SAID CRANKCASE WITH SAID INTAKE MANIFOLD MEANS FOR CONDUCTING CRANKCASE FUMES TO SAID INTAKE MANIFOLD MEANS, A FLOW RESTRICTING ORIFICE INTERPOSED IN SAID CONDUIT MEANS, AND A NORMALLY CLOSED CHECKVALVE MEANS WHILE RESPONSIVE TO INTAKE MANIFOLD VACUUM TO PERMIT CRANKCASE FUMES TO PASS THERETHROUGH EN ROUTE TO SAID INTAKE MANIFOLD MEANS IN SAID CONDUIT MEANS CONSTANTLY EFFECTIVE TO PREVENT FLOW OF AIR AND GAS FROM THE INTAKE MANIFOLD INTO SAID CRANKCASE THROUGH SAID CONDUIT MEANS.