Vacuum operated oil level indicator

Claim 1

A CONDITION INDICATOR FOR AN AUTOMOBILE LUBRICATING SYSTEM HAVING A PUMP AND A NORMALLY OPEN PRESSURE SWITCH ASSOCIATED THEREWITH, SAID CONDITION INDICATOR COMPRISING: VALVE MEANS HAVING AN INLET FROM THE INTAKE MANIFOLD AND AN OUTLET REMOTELY POSITIONED FROM SAID INLET, SAID VALVE MEANS INCLUDING A PISTON NORMALLY BIASED IN ONE DIRECTION AND MOVABLE TO BRING THE INLET INTO FLUID COMMUNICATION WITH THE OUTLET; PRESSURE RESPONSIVE MEANS INCLUDING A SPRING LOADED DIAPHRAGM IN PRESSURE COMMUNICATION WITH THE OUTLET OF THE VALVE MEANS, SAID PRESSURE RESPONSIVE MEANS INCLUDING SWITCHING MEANS IN NORMALLY CLOSED DISPOSITION BEING RESPONSIVE TO MOVEMENT OF THE DIAPHRAGM TO AN OPEN POSITION; A PRESSURE LINE CONNECTING THE PRESSURIZED PORTION OF THE PRESSURE RESPONSIVE MEANS AND AN OIL RESERVOIR, SAID DIAPHRAGM FURTHER PROVIDING A MEANS FOR BLOCKING FLUID FLOW BETWEEN THE OUTLET OF SAID VALVE MEANS AND SAID PRESSURE LINE, AN OPPOSITE END OF THE PRESSURE LINE BEING DISPOSED AT A PREDETERMINED LEVEL IN THE OIL RESERVOIR CORRESPONDING TO A MINIMUM ACCEPTABLE LEVEL OF OIL THEREIN; INDICATING MEANS ENERGIZABLE BY MOVEMENT OF THE PISTON IN THE VALVE MEANS AND INCLUDING A CIRCUIT ESTABLISHED BETWEEN A TELL-TALE LAMP AND AN ELECTRICAL SOURCE THROUGH THE SWITCHING MEANS FORMED AS A PORTION OF THE PRESSURE RESPONSIVE MEANS; SAID PRESSURE RESPONSIVE MEANS BEING POSITIONED BY KEEP ENERGIZED THE CIRCUIT ESTABLISHED BETWEEN THE TELL-TALE LAMP AND THE ELECTRICAL SOURCE AS THE PISTON OF THE VALVE MEANS IS MOVED IN ONE DIRECTION WHEN THE OIL LEVEL IN THE RESERVOIR HAS DROPPED BELOW THE OPPOSITE END OF THE PRESSURE LINE, THE PRESSURE RESPONSIVE MEANS ADAPTED TO DEENERGIZE THE CIRCUIT ESTABLISHED BY MOVEMENT OF THE PISTON BETWEEN THE TELL-TALE LAMP AND THE ELECTRICAL SOURCE WHEN THE OIL LEVEL IN THE RESERVOIR IS ABOVE THE MINIMUM ACCEPTABLE LEVEL, SAID TELL-TALE LAMP BEING ALTERNATELY ENERGIZED DIRECTLY BY A CLOSING OF SAID PRESSURE SWITCH IF PUMP PRESSURE DECREASES BELOW PREDETERMINED LIMITS.