Material spreaders having remote controls

Claim 1

IN A VEHICLE HAVING AN OPERATOR''S STATION. A FIRST MOTOR FOR PROPELLING SAID VEHICLE, AN AUXILIARY DRIVEN DEVICE ON SAID VEHICLE, AUXILIARY MOTOR MEANS ON SAID VEHICLE REMOTE FROM THE OPERATOR''S STATION FOR DRIVING SAID AUXILIARY DRIVEN DEVICE, A SPEED CONTROL FOR SAID AUXILIARY MOTOR MEANS, A REVERSIBLE ELECTRIC CONTROL MOTOR, MECHANICAL MEANS BETWEEN SAID ELECTRIC CONTROL MOTOR AND THE SPEED CONTROL FOR SAID AUXILIARY MOTOR MEANS FOR CONTROLLING THE OPERATION OF THE LATTER AND HENCE THE OPERATION OF SAID AUXILIARY DEVICE IN ACCORDANCE WITH THE OPERATION OF SAID ELECTRIC CONTROL MOTOR, A FIRST ELECTRIC CIRCUIT FOR SAID ELECTRIC CONTROL MOTOR, A REVERSING SWITCH IN SAID FIRST CIRCUIT, AN ELECTRIC BRIDGE CIRCUIT, A MASTER VARIABLE RESISTANCE MEANS WITH A MOVABLE WIPER IN SAID BRIDGE CIRCUIT AND LOCATED IN THE OPERATOR''S STATION, A SLAVE VARIABLE RESISTANCE MEANS IN SAID BRIDGE CIRCUIT AND HAVING ITS RESISTANCE IN PARALLEL WITH THE RESISTANCE OF SAID MASTER MEANS AND HAVING A MOVABLE WIPER, CONDUCTING MEANS INCLUDING A DISCRIMINATING RELAY ELECTRICALLY CONNECTING SAID WIPERS, ELECTRIC MEANS BETWEEN SAID DISCRIMINATING RELAY AND THE REVERSING SWITCH IN SAID FIRST ELECTRIC CIRCUIT FOR CAUSING OPERATION OF SAID ELECTRIC CONTROL MOTOR IN A SELECTED DIRECTION IN ACCORDANCE WITH THE ACTION OF SAID DISCRIMINATING RELAY WHEN THE BRIDGE CIRCUIT IS UNBALANCED DUE TO A CHANGE IN THE POSITION OF THE WIPER OF THE MASTER VARIABLE RESISTANCE MEANS, AND MEANS BETWEEN SAID ELECTRIC CONTROL MOTOR AND WIPER OF THE SLAVE VARIABLE RESISTANCE MEANS FOR CHANGING THE POSITION OF THE LATTER TO BRING THE CONTROL CIRCUIT BACK INTO BALANCE WHEREBY MOVEMENT OF THE WIPER OF THE MASTER VARIABLE RESISTANCE MEANS WILL CONTROL THE OPERATION OF THE SPEED CONTROL FOR THE AUXILIARY MOTOR MEANS, THERE BEING A VARIABLE SIGNAL SENDER WHICH IS RESPONSIVE TO THE GROUND SPEED OF THE VEHICLE IN SERIES WITH THE DISCRIMINATING RELAY.