Fluid level indicator

Claim 1

IN A FLUID LEVEL INDICATOR SYSTEM FOR THE OIL SUMP OF AN INTERNAL COMBUSTION AUTOMOTIVE VEHICLE AND THE LIKE, A SWITCH DEVICE COMPRISING A VERTICAL CYLINDRICAL METAL CAN, A FLUID INLET TUBE HAVING ONE END CONNECTED TO THE BOTTOM OF SAID CAN AND THE OTHER END IN COMMUNICATION WITH SAID OIL SUMP, A COVER OF INSULATING MATERIAL FOR SAID CAN, THE UPPER PART OF SAID CAN BEING VENTED TO PERMIT RISE AND FALL OF THE OIL LEVEL THEREIN CORRESPONDING TO THAT IN SAID SUMP, A CONDUCTIVE SPIDER INSIDE THE LOWER END OF SAID CAN, A CENTRAL VERTICAL CONDUCTIVE STUD MOUNTED ON SAID SPIDER SPACED UPWARDLY THERBY FROM THE BOTTOM OF SAID CAN, AN ELECTRIC SWITCH COMPRISING AN ELONGATED SEALED NON-CONDUCTIVE TUBE HAVING A PAIR OF MAGNETIZABLE CONTACT ELEMENTS EXTENDING LONGITUDINALLY INWARDLY FROM THE RESPECTIVE ENDS OF SAID TUBE WITH NORMALLY RESILIENTLY SPACED OVERLAPPING END PORTIONS ADAPTED TO BE DRAWN INTO CONTACT WITH EACH OTHER BY A MAGNETIC FIELD SURROUNDING SAID OVERLAPPING END PORTIONS, THE LOWER END OF SAID TUBE BEING MOUNTED ON SAID STUD WITH THE CORRESPONDING SAID CONTACT ELEMENT ELECTRICALLY CONNECTED WITH THE LATTER, THE UPPER END OF SAID TUBE BEING RECEIVED IN A RECESS IN SAID COVER, A FLOAT WITHIN SAID CAN HAVING A VERTICAL BORE THROUGH WHICH SAID TUBE PASSES, SAID FLOAT BEING ADAPTED TO REST UPON SAID SPIDER IN LOWERMOST POSITON AND BEING OF A LENGTH LESS THAN THE DISTANCE BETWEEN SAID SPIDER AND SAID COVER TO PERMIT SUBSTANTIAL VERTICAL RECIPROCATION OF SAID FLOAT AS THE FLUID LEVEL WITHIN SAID CAN RISES AND FALLS, AN ANNULAR PERMANENT MAGNET SUPPORTED BY SAID FLOAT AND ENCIRCLING SAID TUBE, SAID MAGNET POSITIONED ON SAID FLOAT TO LIE IN THE SAME HORIZONTAL PLANE AS THE OVERLAPPING END PORTIONS OF SAID CONTACT ELEMENTS WHEN SAID FLOAT IS IN ENGAGEMENT WITH SAID SPIDER TO PROVIDE SAID MAGNETIC FIELD, AND AN ELECTRIC BATTERY AND SIGNAL MEANS IN CIRCUIT WITH SAID SWITCH, SAID SIGNAL MEANS BEING ADAPTED TO BE ACTUATED BY SAID BATTERY WHEN SAID SWITCH IS CLOSED TO SIGNAL THAT THE FLUID IN SAID OIL SUMP HAS DROPPED TO A PREDETERMINED LEVEL.