Control valve means for forward and reverse clutches

Claim 1

CONTROL VALVE MEANS FOR SELECTIVELY ACTUATING FORWARD AND REVERSE CLUTCHES OF A TRUCK TRANSMISSION TO PROVIDE INCHING OF THE TRUCK AND COMPRISING A VALVE HOUSING HAVING A VALVE CHAMBER INCLUDING A VALVE CYLINDER, A VALVE ELEMENT SLIDABLY MOUNTED IN SAID CYLINDER, FIRST PASSAGEWAY MEANS COMMUNICATING WITH SAID VALVE CYLINDER FOR CONNECTION TO A SOURCE OF HYDRAULIC FLUID UNDER PRESSURE, MEANS IN SAID VALVE CHAMBER INCLUDING SAID VALVE ELEMENT FORMING A FIRST EXPANDABLE CHAMBER, MEANS IN SAID VALVE CHAMBER INCLUDING SAID VALVE ELEMENT FORMING A SECOND EXPANDABLE CHAMBER, A FIRST PASSAGEWAY IN SAID VALVE ELEMENT FOR INTERCONNECTING SAID FIRST PASSAGEWAY MEANS AND SAID FIRST EXPANDABLE CHAMBER, A SECOND PASSAGEWAY IN SAID VALVE ELEMENT FOR INTERCONNECTING SAID FIRST PASSAGEWAY MEANS AND SAID SECOND EXPANDABLE CHAMBER, SECOND PASSAGEWAY MEANS COMMUNICATING WITH SAID FIRST AND SECOND EXPANDABLE CHAMBERS FOR CONNECTION TO THE LUBRICATING SYSTEM OF THE TRTUCK AND INCLUDING A FIRST PORT IN SAID FIRST EXPANDABLE CHAMBE AND A SECOND PORT IN SAID SECOND EXPANDABLE CHAMBER, SAID FIRST PORT BEING AT LEAST PARTIALLY CLOSED UPON MOVEMENT OF SAID VALVE ELEMENT IN A FIRST DIRECTION AND SAID SECOND PORT BEING AT LEAST PARTIALLY CLOSED BY MOVEMENT OF SAID VALVE ELEMENT IN A SECOND DIRECTION; THIRD PASSAGEWAY MEANS COMMUNICATING WITH SAID VALVE CYLINDER FOR CONNECTION TO A FIRST FLUID ACTUATED CLUTCH, FOURTH PASSAGEWAY MEANS COMMUNICATING WITH SAID VALVE CYLINDER FOR CONNECTION TO A SECOND FLUID ACTUATED CLUTCH, MEANS INCLUDING SAID VALVE ELEMENT FOR PLACING SAID FIRST PASSAGEWAY SELECTIVELY IN COMMUNICATION WITH SAID THIRD AND FOURTH PASSAGEWAY MEANS, SAID VALVE ELEMENT BEING PROVIDED WITH MEANS FOR MAINTAINING SAID FIRST PASSAGEWAY MEANS AND SAID FIRST EXPANDABLE CHAMBER IN COMMUNICATION WHEN SAID VALVE ELEMENT IS MOVED IN SAID FIRST DIRECTION AND CLOSING SAID FIRST PASSAGEWAY MEANS RELATIVE TO SAID FIRST EXPANDABLE CHAMBER WHEN SAID VALVE ELEMENT IS MOVED IN SAID SECOND DIRECTION AND ADDITIONALLY PROVIDED WITH MEANS MAINTAINING SAID FIRST PASSAGEWAY MEANS AND SAID SECOND EXPANDABLE CHAMBER IN COMMUNICATION WHEN SAID VALVE ELEMENT IS MOVED IN SAID SECOND DIRECTION AND CLOSING SAID FIRST PASSAGEWAY MEANS RELATIVE TO SAID SECOND EXPANDABLE CHAMBER WHEN SAID VALVE IS MOVED IN SAID FIRST DIRECTION, ACTUATING MEANS OPERABLE TO MOVE SAID VALVE ELEMENT IN SAID FIRST AND SECOND DIRECTIONS TOWARD A POSITION TO CONTRACT SAID EXPANDABLE CHAMBERS TO CLOSE SAID FIRST AND SECOND PORTS RESPECTIVELY TO PROVIDE A PRESSURE BUILD-UP IN THE RESPECTIVE ONE OF SAID CHAMBERS WHICH TENDS TO EXPAND SAID CHAMBERS, AND SPRING MEANS CONNECTED TO RESILIENTLY RESTRAIN THE EXPANSION OF SAID EXPANDABLE CHAMBERS DUE TO THE PRESSURE THEREIN SO AS TO AT LEAST PARTIALLY MAINTAIN OPEN SAID FIRST AND SECOND PORTS RESPECTIVELY UNTIL THE PRESSURE IN THE ASSOCIATED EXPANDABLE CHAMBER IS IN EQUILIBRIUM WITH THE RESTRAINING FORCE OF THE SPRING MEANS, THE RESTRAINING FORCE OF SAID SPRING MEANS BEING A FUNCTION OF THE DISTANCE THROUGH WHICH ACTUATING MEANS IS MOVED.