Differential pressure responsive apparatus

Claim 1

APPARATUS FOR MEASURING THE FLOW OF A GAS AND FOR PRODUCING A SIGNAL CORRESPONDING TO THE MEASURED FLOW, COMPRISING, IN COMBINATION: MEANS IN THE FLOWING GAS STREAM TO CREATE A PRESSURE DROP AND TO DEVELOP A DIFFERENTIAL PRESSURE SIGNAL CORRESPONDING THERETO, FIRST SENSING MEANS COMPRISING A PRESSURE CELL RESPONSIVE TO SAID DIFFERENTIAL PRESSURE TO PRODUCE A FIRST INPUT FORCE-SIGNAL CORRESPONDING TO SAID DIFFERENTIAL PRESSURE SIGNAL, A FORCE BAR COUPLED AT ONE END THEREOF TO SAID PRESSURE CELL TO BE ACTED ON BY SAID FIRST INPUT FORCE-SIGNAL, SECOND SENSING MEANS RESPONSIVE TO A CHARACTERISTIC OF SAID GAS FOR PRODUCING A SECOND FORCE-SIGNAL PROPORTIONAL TO THE VALUE OF SAID CHARACTERISTIC; A FIRST STAGE MECHANISM FOR PRODUCING AN INTERMEDIATE SIGNAL REPRESENTING THE PRODUCT OF SAID FIRST AND SECOND FORCE-SIGNAL, SAID MECHANISM COMPRISING A FIRST BALANCEABLE MEMBER, MEANS CONNECTING THE OTHER END OF SAID FORCE BAR TO SAID BALANCEABLE MEMBER TO TRANSMIT THERETO A FORCE CORRESPONDING TO SAID FIRST FORCE-SIGNAL; A FIRST REACTION ELEMENT, A CONNECTING FLEXURE DIRECTLY SECURING SAID REACTION ELEMENT TO SAID BALANCEABLE MEMBER SO THAT SAID REACTION ELEMENT SERVES TO CONTROL THE EXTENT OF MOVEMENT OF SAID BALANCEABLE MEMBER IN RESPONSE TO CHANGES IN FORCE APPLIED THERETO, FIRST FORCE-TRANSMITTING MEANS FOR APPLYING A FORCE TO SAID BALANCEABLE MEMBER, SECOND FORCE-TRANSMITTING MEANS FOR ADJUSTING THE ANGULAR POSITION OF SAID REACTION ELEMENT WITH RESPECT TO SAID BALANCEABLE MEMBER SO AS TO ADJUST THE EXTENT OF MOVEMENT OF SAID BALANCEABLE MEMBER IN RESPONSE TO CHANGES IN FORCE THEREON, FIRST FEEDBACK MEANS RESPONSIVE TO MOVEMENT OF SAID BALANCEABLE MEMBER FOR PRODUCING A REBALANCE SIGNAL CORRESPONDING TO ANY UNBALANCE OF FORCES ON SAID MEMBER, MEANS FOR DIRECTING SAID SECOND FORCE-SIGNAL TO ONE OF SAID FORCE-TRANSMITTING MEANS, MEANS FOR DIRECTING SAID REBALANCE SIGNAL TO THE OTHER OF SAID FORCE-TRANSMITTING MEANS TO MAINTAIN THE FORCES ON SAID MEMBER IN BALANCE, SAID BALANCE SIGNAL THEREBY SERVING AS SAID INTERMEDIATE SIGNAL AND REPRESENTING BY ITS MAGNITUDE THE PRODUCT OF SAID FIRST AND SECOND FORCESIGNALS; AND A SECOND STAGE MECHANISM PHYSICALLY MOUNTED TOGETHER WITH SAID FIRST STAGE MECHANISM AND STRUCTURALLY SIMILAR THERETO, SAID SECOND STAGE MECHANISM SERVING TO PRODUCE A FINAL OUTPUT SIGNAL CORRESPONDING TO A SQAURE-ROOT FUNCTION OF THE QUANTITY REPRESENTED BY SAID INTERMEDIATE SIGNAL, SO THAT THE FINAL OUTPUT SIGNAL IS LINEARLY RELATED TO THE GAS FLOW RATE, SAID SECOND STAGE MECHANISM COMPRISING A SECOND BALANCEABLE MEMBER, A SECOND REACTION ELEMENT SECURED TO SAID SECOND BALANCEABLE MEMBER BY A SECOND CONNECTING FLEXURE, A SET OF THREE FORCE-TRANSMITTING MEANS CONSISTING OF THIRD AND FOURTH FORCETRANSMITTING MEANS FOR APPLYING TRANSVERSELY-DIRECTED FORCES TO SAID BALANCEABLE MEMBER AND A FIFTH FORCETRANSMITTING MEANS FOR ADJUSTING THE ANGULAR POSITION OF SAID SECOND REACTION ELEMENT WITH RESPECT TO SAID SECOND BALANCEABLE MEMBER, SECOND FEEDBACK MEANS RESPONSIVE TO MOVEMENT OF SAID SECOND BALANCEABLE MEMBER FOR MOVEMENT OF SAID SECOND BALANCEABLE SPONDING TO ANY UNBALANCE OF FORCES ON SAID SECOND BALANCEABLE MEMBER, MEANS FOR DIRECTING SAID INTERMEDIATE SIGNAL TO ONE OF SAID SET OF THREE FORCETRANSMITTING MEANS, AND MEANS FOR DIRECTING SAID REBALANCE SIGNAL TO THE REMAINING TWO FORCE-TRANSMITTING MEANS OF SAID SET, SO THAT SAID SECOND REBALANCE SIGNAL SERVES AS A FINAL OUTPUT SIGNAL CORRESPONDING TO THE SQUARE-ROOT OF THE PRODUCT OF THE SIGNALS REPRESENTING SAID GAS FLOW RATE AND SAID CHARACTERISTIC RESPECTIVELY.