Actuating and control system for a pressure fluid operated track displacement apparatus

Claim 1

IN A PRESSURE FLUID OPERATED TRACK DISPLACEMENT APPARATUS, COMPRISING A PRESSURE FLUID, CYLINDER MEANS INCLUDING A CYLINDER AND A PISTON WITH AN ASSOCIATED PISTON ROD SLIDABLY SUPPORTED IN SAID CYLINDER, A TRACK ENGAGING MEANS CONNECTED WITH SAID CYLINDER MEANS, AND A PRESSURE FLUID CONDUIT ARRANGED TO SUPPLY PRESSURE FLUID TO THE CYLINDER FOR MOVING THE CYLINDER MEANS THROUGH A TRACK DISPLACEMENT STROKE: AN ACTUATING AND CONTROL SYSTEM FOR THE PRESSURE FLUID SUPPLY, SAID SYSTEM COMPRISING A VALVE MEANS IN SAID PRESSURE FLUID CONDUIT, SAID VALVE MEANS HAVING AN OPEN AND A NORMALLY CLOSED POSITION, AN ELECTRIC CONTROL CIRCUIT, A POWER SOURCE DELIVERING ELECTRIC CURRENT TO SAID CIRCUIT, MEANS FOR HOLDING THE VALVE MEANS IN THE NORMALLY CLOSED POSITION, ELECTRO-MAGNETIC MEANS CONNECTED IN SAID CIRCUIT AND ENERGIZABLE BY THE CURRENT FOR MOVING THE VALVE MEANS FROM SAID NORMALLY CLOSED INTO THE OPEN POSITION, FIRST SWITCH MEANS IN THE CIRCUIT, SAID SWITCH MEANS BEING ACTUATABLE TO CLOSE THE CIRCUIT FOR ENERGIZATION OF THE ELECTRO-MAGNETIC MEANS, ENERGIZATION OF THE ELECTROMAGNET MEANS BRINGING THE VALVE MEANS INTO THE OPEN POSITION WHEREBY PRESSURE FLUID IS SUPPLIED TO THE CYLINDER, ACTUATING MEANS RESPONSIVE TO THE SUDDEN PRESSURE INCREASE CAUSED IN THE PRESSURE FLUID CONDUIT BY THE INCEPTION OF THE TRACK DISPLACEMENT STROKE, A SECOND SWITCH MEANS IN SAID CIRCUIT, SAID SECOND SWITCH MEANS BEING NORMALLY OPEN AND BEING CLOSABLE BY SAID PRESSURE INCREASE RESPONSIVE MEANS UPON THE SAID SUDDEN PRESSURE INCREASE, AN ADJUSTABLE TIME-DELAY RELAY IN SAID CIRCUIT, SAID RELAY BEING ENERGIZED UPON CLOSING OF THE SECOND SWITCH MEANS, A THIRD SWITCH MEANS IN THE CIRCUIT, SAID THIRD SWITCH MEANS BEING NORMALLY OPEN AND BEING CLOSABLE BY SAID TIME-DELAY RELAY, MEANS FOR ADJUSTING THE RELAY TO A DESIRED TIME LAG, AND MEANS FOR OPENING THE FIRST SWITCH MEANS, SAID SWITCH OPENING MEANS BEING CONNECTED IN THE CIRCUIT AND BEING OPERATED WHEN SAID THIRD SWITCH MEANS IS CLOSED BY THE TIME-DELAY RELAY, OPENING OF THE FIRST SWITCH MEANS CAUSING DE-ENERGIZATION OF THE ELECTRO-MAGNETIC MEANS AND RETURN OF THE VALVE MEANS INTO THE NORMALLY CLOSED POSITION.