Automatic submersible pump

Claim 1

IN COMBINATION, A SUBMERSIBLE PUMP, A MOTOR FOR DRIVING SAID PUMP, AND AN AUTOMATIC CONTROL DEVICE MOUNTED ON SAID PUMP FOR CONTROLLING THE OPERATION OF SAID PUMP MOTOR IN RESPONSE TO CHANGES IN THE WATER LEVEL AROUND SAID PUMP, SAID AUTOMATIC CONTROL DEVICE COMPRISING VERTICALLY SPACED UPPER AND LOWER ELECTRODES WHICH WHEN SUBMERGED ARE ADAPTED TO BE ELECTRICALLY CONNECTED TO AN EARTH OF SAID CONTROL DEVICE BY CONDUCTION THROUGH THE WATER IN WHICH THE PUMP IS IMMERSED, A TRANSFORMER HAVING A PRIMARY CIRCUIT WHICH IS ADAPTED TO BE CONNECTED TO A POWER SUPPLY AND A SECONDARY CIRCUIT, A RECTIFIER HAVING ONE INPUT TERMINAL CONNECTED TO ONE TERMINAL OF SAID SECONDARY CIRCUIT AND THE OTHER INPUT TERMINAL CONNECTED TO SAID UPPER ELECTRODE, THE OTHER TERMINAL OF SAID SECONDARY CIRCUIT BEING CONNECTED TO THE EARTH, A FIRST RELAY COIL CONNECTED ACROSS THE OUTPUT TERMINALS OF SAID RECTIFIER, A SECOND RELAY COIL A FIRST SWITCH CLOSED BY ENERGIZATION OF SAID FIRST RELAY COIL, SAID FIRST SWITCH BEING CONNECTED IN SERIES WITH SAID SECOND RELAY COIL ACROSS THE TRANSFORMER PRIMARY CIRCUIT FOR ENERGIZING SAID SECOND RELAY COIL WHEN SAID FIRST SWITCH IS CLOSED, SAID SECOND RELAY COIL, WHEN ENERGIZED, CLOSING ANOTHER SWITCH IN THE MOTOR CIRCUIT TO ACTUATE SAID PUMP MOTOR, AND A CHANGE-OVER SWITCH MEANS DIRECTLY COUPLED TO SAID MOTOR CIRCUIT SWITCH OPERATIVE TO MAKE A CONNECTION BETWEEN SAID LOWER ELECTRODE AND THE INPUT TERMINAL OF SAID RECTIFIER WHICH IS ALSO CONNECTED WITH SAID UPPER ELECTRODE IN RESPONSE TO THE CLOSING OF SAID MOTOR CIRCUIT SWITCH, WHEREBY SAID TRANSFORMER SECONDARY CIRCUIT WILL REMAIN CLOSED AND SAID PUMP MOTOR WILL CONTINUE TO OPERATE AS LONG AS SAID LOWER ELECTRODE IS CONDUCTIVELY CONNECTED TO THE EARTH THROUGH THE WATER IN WHICH THE PUMP IS EMERGED.