Liquid level indicating device

Claim 1

A LIQUID LEVEL INDICATING DEVICE FOR USE WITH A VESSEL CONFINING A LIQUID COMPRISING IN COMBINATION A METAL BASE HAVING A SCREW THREAD THEREON FOR FACILE CONNECTION TO SAID VESSEL, A METAL COVER CONNECTED TO THE BASE AND DEFINING WITHIN THE CONFINES OF THE COVER AND BASE A GENERALLY ELONGATED CAVITY, A REED SWITCH SUPPORTED WITHIN THE CAVITY AND EXTENDING AXIALLY THEREOF, SAID REED SWITCH INCLUDING A SEALED ENCLOSURE AND A PAIR OF ELONGATED SLENDER REEDS HAVING ENDS DISPOSED INSIDED AND OUTSIDE OF THE SEALED ENCLOSURE, A TERMINAL CARRIED BY SAID BASE AND INSULATED THEREFEOM, THE EXTERNAL ENDS OF THE REEDS BEING CONNECTED, RESPECTIVELY, TO SAID COVER AND TERMINAL FOR EXTENDING RESPECTIVE ELECTRICAL CONNECTIONS, THE INTERNAL ENDS OF SAID REEDS OVERLAPPING ONE ANOTHER SLIGHTLY TO PROVIDE SWITCH CONTACTS, A FLOAT ENCIRCLING SAID SWITCH INSIDE SAID COVER AND BUOYED BY THE LIQUID WITHIN THE CAVITY FOR AXIAL MOVEMENT IN SAID CAVITY RELATIVE TO SAID SWITCH, AN ANNULAR MAGNET SUPPORTED BY THE FLOAT, SAID MAGNET BEING MAGNETIZED WITH THE LINES OF FLUX DISPOSED AXIALLY OF THE LONGITUDINAL CENTER AXIS OF THE MAGNET AND IN LINE GENERALLY WITH THE AXIS OF THE REED SWITCH SAID REEDS BEING FABRICATED OF MAGNETIZABLE MATERIAL AND SAID COVER AND FLOAT BEING FABRICATED OF NONMAGNETIZABLE MATERIAL SO THAT AT VARIOUS POSITIONS OF THE FLOAT DETERMINED BY THE LEVEL OF LIQUID IN THE CAVITY THE PROXIMITY OF THE MAGNET TO THE CONTACTS ACTUATES THE REEDS TO OPEN AND CLOSE THE SWITCH CONTACTS, SAID COVER HAVING THEREIN AT LEAST ONE OPENING EXTENDING FROM PROXIMATE THE OPPOSITE ENDS OF THE CAVITY OPERABLE TO COMMUNICATE THE LIQUID WITHIN THE VESSEL TO AND FROM THE CAVITY, AND AN ADJUSTABLE POSITIONED NONNAGNETIZABLE FILTER EXTENDING OVER SAID ONE OPENING IN SAID COVE FOR SELECITIVELY DAMPING ANY FLOW OF LIQUID THROUGH THE OPENING.