Jet pipe regulator with null position adjustment

Claim 1

IN A HYDRAULIC CONTROL SYSTEM HAVING A JET PIPE WITH A NOZZLE AT ONE END THEREOF AND INCLUDING MEANS FOR CONNECTING PRESSURE FLUID THERETO AND MEANS FOR SHIFTING THE PIPE IN OPPOSITE DIRECTIONS FROM A STATIONARY NULL POSITION, THE COMBINATION OF A RECEIVER PORT MEMBER HAVING A SURFACE WITH TWO RECEIVER PORTS OPENING THERETO, SAID PORTS BEING INDEPENDENTLY CONNECTED TO OPPOSITELY DISPOSED END CHAMBERS IN WHICH ARE RESPECTIVELY EXPOSED PRESSURE EFFECTIVE OPPOSED END SURFACES OF THE RECEIVER PORT MEMBER, SAID CHAMBERS BEING ADAPTED FOR CONNECTION TO AN OUTPUT MEMBER, SAID RECEIVER PORT MEMBER, WITH THE JET PIPE IN THE NULL POSITION AND PRESSURE FLUID CONNECTED TO THE JET PIPE, BEING SHIFTABLE IN OPPOSITE DIRECTIONS IN RESPONSE TO A DIFFERENTIAL OF PRESSURE ON THE END SURFACES OF SAID MEMBER UNTIL THE RECEIVER PORTS ARE CENTERED RELETIVE TO THE JET PIPE NOZZLE AT WHICH TIME A PRESSURE BALANCE EXISTS AT THE OPPOSED ENDS OF THE MEMBER, AND MEANS FOR LOCKING SAID RECEIVER PORT MEMBER IN THE CENTERED POSITION RELATIVE TO THE NOZZLE WHILE SAID JET PIPE IS IN THE NULL POSITION FOR NORMAL OPERATION OF SAID CONTROL SYSTEM.