Material level detector

Claim 1

APPARATUS FOR DETECTING THE LEVEL OF MATERIAL RESIDING WITHIN PRE-ESTABLISHED LIMITS WITHIN A TANK COMPRISING: (A) A ROTATING MATERIAL CONTACTOR ADAPTED TO MOVE UP AND DOWN WITHIN THE TANK, (B) A REVERSIBLE, ELECTRICALLY ENERGIZED DRIVE MEANS WHICH RAISES SAID MATERIAL CONTACTOR WITHIN THE TANK WHEN THE DRIVE MEANS IS ENERGIZED IN ONE DIRECTION AND WHICH LOWERS THE MATERIAL CONTACTTOR WITHIN THE TANK WHEN ENERGIZED IN THE REVERSE DIRECTION, (C) A DOUBLE-THROW SWITCH WHICH IS ACTUATED TO A FIRST RELATION OF THROW BY A TORQUE FORCE CREATED UPON ENGAGEMENT OF SAID ROTATING CONTACTOR WITH MATERIAL IN THE TANK AND WAHICH IS ACTUATED BY SPRING TENSION TO A SECOND RELATION OF THROW UPON DISENGAGEMENT OF SAID CONTACTOR WITH MATERIAL IN THE TANK, (D) MEANS FOR SUPPLYING ENERGIZING CURRENT TO THE ELECTRICALLY OPERATED DRIVE MEANS THROUGH THE DOUBLETHROW SWITCH, SAID DRIVER MEANS BEING GENERGIZED IN A DIRECTION WHICH RAISES SAID MATERIAL CONTACTOR WHEN TO DOUBLE-THROW SWITCH IS IN THE FIRST RELATION OF THROW SWITCH, SAID DRIVE MEANS BEING ENERGIZED IN A REVERSE DIRECTION WHEN THE DOUBLE-THROW SWITCH IS ACTUATED TO THE SECOND RELATION OF THROW, WHEREBY SAID MATERIAL CONTACTING MEANS IS REPEATEDLY AND AUTOMATICALLY RAISED AND LOWERED BY INTERRUPTIVE ENGAGEMENT OF THE ROTATING CONTACTOR WITH MATERIAL CONTAINER IN THE TANK.