Integrating and proportional flow control apparatus

Claim 1

A VALVE ASSEMBLY FOR CONTROLLING THE FLUID PRESSURE DIFFERENTIAL ACROSS A VARIABLE SIZE FLUID RESTRICTED ORFICE COMPRISING: A HOUSING HAVING A PORT OF PERMITTING THE FLOW OF FLUID, A FIRST MOVABLE VALVE MEMBER CONTAINED IN SAID HOUSING AND SLIDABLE IN FIRST AND SECOND DIRECTIONS, SAID FIRST MOVABLE MEMBER INCLUDING A PATTERN OF HOLES OPERATIVE WITH SAID PORT OF FORM A VARIABLE FLUID FLOW PERMITTING AREA WHICH INCREASES IN EFFECTIVE FLOW PERMITTING AREA WHEN SAID FIRST MOVABLE MEMBER MOVES IN SAID FIRST DIRECTION AND DECREASES IN EFFECTIVE FLOW PERMITTING AREA WHEN SAID FIRST MOVABLE VALVE MEMBER MOVES IN SAID SECOND DIRECTION, CONDUIT MEANS CONNECTING SAID VARIABLE FLUID FLOW PERMITTING AREA WITH THE VARIABLE SIZE ORIFICE SUCH THAT THE FLUID FLOW THROUGH AND PRESSURE DIFFERENTIAL ACROSS THE VARIABLE SIZE ORFICE IS CONTROLLED AS A FUNCTION OF THE EFFECTIVE AREA OF SAID VARIABLE FLUID FLOW PERMITTING AREA, A SERVO PISTON CONNECTED TO SAID FIRST MOVABLE VALVE MEMBER AND OPERATIVE TO POSITION SAID FIRST MOVABLE VALVE MEMBER IN SAID FIRST AND SECOND DIRECTIONS AS A FUNCTION OF A CONTROL FLUID PRESSURE ACTING THEREON, HEAD SENSING MEANS OPERATIVE TO SENSE THE PRESSURE DIFFERENTIAL ACROSS THE VARIABLE SIZE ORFICE, SAID HEAD SENSING MEANS INCLUDING A SERVO CONTROL DEVICE AND CONNECTED TO SAID SERVO PISTON TO VARY THE CONTROL FLUID PRESSURE ACTING THEREON AS A FUNCTION OF THE PRESSURE DIFFERNTIAL ACROSS THE VARIABLE SIZE ORFICE, A SECOND MOVABLE VALVE MEMBER CONTAINED WITHIN SAID FIRST MOVABLE MEMBER AND ALSO MOVABLE IN SAID FIRST AND SECONE DIRECTIONS, SAID SECOND MOVABLE MEMBER INCLUDING A METERING EDGE OPERATIVE WITH SAID PATTERN OF HOLES TO VARY THE EFFECTIVE FLOW PERMITTING AREA THEREOF AS A FUNCTION OF THE POSITION OF SAID SECOND MOVABLE VALE MEMBER, AND MEANS FOR TRANSMITTING THE FLUID PRESSURE DIFFERENTIAL ACROSS THE VARIABLE SIZE ORIFICE TO SAID SECOND MOVABLE VALVE MEMBER SUCH THAT SAID SECOND MOVABLE VALVE MEMBER IS POSITIONED AS A FUNCTION OF THE PRESSURE DIFFERENTIAL ACROSS THE VARIABLE SIZE ORFICE.