Fluid control valves

Claim 1

A MOULDING MACHINE COMPRISING, IN COMBINATION, A FRAME, RELATIVELY MOVABLE MOULD-FORMING COMPONENTS MOUNTED ON SAID FRAME AND FORMING A VARIABLE CAPACITY MOULDING CAVITY, A FLUID CYLINDER UNIT ON SAID FRAME HAVING A RAM MOVABLE WITH ONE OF SAID MOULD FORMING COMPONENTS AND CONSTITUTING A DISPLACEABLE COMPONENT FOR WITHDRAWAL AT A CONTROLLED RATE TO EFFECT SLIGHT INCREASE IN THE VOLUMETRIC CAPACITY OF THE MOULDING CAVITY, AND A CONTROL UNIT FOR CONTROLLING DISPLACEMENT OF SAID DISPLACEABLE COMPONENT, SAID CONTROL UNIT COMPRISING A VALVE BODY CONNECTED TO SAID RAM SO AS TO BE MOVABLE THEREWITH AND HAVING AN ORIFICE THEREIN, A PISTON SLIDABLE IN SAID VALVE BODY FOR CONTROLLING THE FLOW OF A FLUID THROUGH SAID ORIFICE AND CONSTRUCTED TO BY-PASS PRESSURE FLUID FLOWING THROUGH SAID ORIFICE, MEANS BIASING SAID PISTON TO A NORMAL POSITION WHEREIN IT EFFECTS CLOSURE OF SAID ORIFICE, CONDUIT MEANS CONNECTING SAID FLUID CYLINDER UNIT TO SAID ORIFICE TO PERMIT DISCHARGE OF FLUID FROM SAID CYLINDER UNIT THROUGH SAID ORIFICE, SAID CLOSURE ACTION OF SAID PISTON SERVING TO THROTTLE THE FLOW OF PRESSURE FLUID BEING DISCHARGED FROM SAID CYLINDER UNIT VIA SAID ORIFICE, AND CONTROL MEANS CONNECTED TO SAID PISTON AND OPERABLE TO ACTUATE THE SAME TO PERMIT FLOW OF PRESSURE FLUID THROUGH SAID ORIFICE AND THEREBY CAUSE WITHDRAWING MOVEMENT OF SAID DISPLACEABLE COMPONENT, SAID CONTROL MEANS COMPRISING MEANS CONNECTED TO SAID PISTON AND OPERABLE TO MOVE THE LATTER RELATIVE TO SAID ORIFICED VALVE BODY AND SAID DISPLACEABLE COMPONENT AND AWAY FROM SAID ORIFICE IN OPPOSITION TO THE BIASING ACTION OF SAID BIASING MEANS, AND MEANS FOR MOVING SAID CONNECTING MEANS TO EFFECT SUCH OPENING OF THE ORIFICE SO THAT SAID DISPLACEABLE COMPONENT IS CAUSED TO BE WITHDRAWN AT A PREDETERMINED RATE, SAID CONTROL MEANS HAVING THE REQUIRED DISPLACEMENT CONSEQUENT UPON FLUID OPERATION OF THE MACHINE TO EFFECT SUBSTANTIALLY SMOOTH TRANSLATIONAL MOVEMENT OF THE ORIFICED VALVE BODY AND OF SAID DISPLACEABLE COMPONENT ASSOCIATED THEREWITH.