Cap and gauge structure for crankcase fill opening

Claim 1

A CAP AND GAUGE FOR THE FILL OPENING OF A CRANKCASE COMPRISING, MEANS PROVIDING A TUBE HAVING A GENERALLY CENTRAL PORTION ADAPTED TO BE DETACHABLY ENGAGED IN CLOSING AND PRESSURE SEALING RELATION TO A FILL OPENING, SAID TUBE HAVING AN END PORTION ADAPTED TO PROJECT TO THE CRANKCASE INTERIOR AND HAVING AN OPENING SUBSTANTIALLY AT THE LOW CRITICAL LEVEL OF OIL IN THE CRANKCASE, SAID TUBE HAVING ANOTHER PORTION WITH A TRANSPARENT SIDE WALL ADAPTED TO PROJECT EXTERIORLY OF THE CRANKCASE, SAID ANOTHER TUBE PORTION HAVING A CLOSURE, MEANS PROVIDING A SMALL ORIFICE IN SAID CLOSURE, MEANS PROVIDING A RESILIENTLY DISTORTABLE VACUUM-PRODUCING BULB SECURED TO SAID OTHER END OF SAID TUBE AND BEING IN COMMUNICATION WITH THE TUBE INTERIOR THROUGH SAID ORIFICE SO THAT PRESSURE FLUCTUATIONS IN SAID CRANKCASE ARE TRANSMITTED TO THE BULB INTERIOR IN DAMPED CONDITION THROUGH SAID ORIFICE, SAID ORIFICE BEING DIMENSIONED TO RESTRICT FLOW OF FLUID INTO SAID BULB UNDER THE RECOVERY FORCE EXERTED BY SAID BULB IN COLLAPSED CONDITION, AND BEING ADEQUATE TO DELAY SUBSTANTIAL RESILIENT RECOVERY OF SAID BULB FOR A PERIOD OF TIME GREATER THAN THAT REQUIRED FOR OIL TO RETURN TO AN ENGINE CRANKCASE SUBSEQUENT TO STOPPING OF THE ENGINE, SAID BULB UPON RECOVERY THEREOF BEING OPERABLE TO DRAW FLUID THROUGH SAID ORIFICE, WHEREBY TO DRAW A COLUMN OF OIL FROM THE CRANKCASE INTO SAID OTHER PORTION.