Apparatus for maintaining clearances in fluid designs substantially constant

Claim 1

APPARATUS FOR KEEPING A CLEARANCE BETWEEN TWO BODIES SUBSTANTIALLY CONSTANT AT A PREDETERMINED VALUE, ONE OF WHICH BODIES SUPPORTS THE OTHER, THROUGH THE INTERMEDIARY OF A PRESSURE OPERATING FLUID IN TWO ZONES OP POSITE EACH OTHER, AGAINST FORCES PRODUCING MOVEMENTS OF SAID OTHER BODY TO ALTER SAID CLEARANCE, WHICH APPARATUS COMPRISES A SOURCE OF PRESSURE GAS, CONTROL MEANS HAVING A CASING WHICH INCORPORATES TWO CHAMBERS, A PRESSURE SENSITIVE ELEMENT SEPARATING THE TWO CHAMBERS FROM EACH OTHER, AND FIRST AND SECOND RESTRICTED ORIFICES PLACING THE TWO CHAMBERS RESPECTIVELY IN COMMUNICATION WITH SAID SOURCE, FIRST AND SECOND OUTLETS THROUGH WHICH GAS CAN ESCAPE FROM ONE OF THE CHAMBERS, A NOZLE AFFORDING SAID FIRST OUTLET AND ADAPTED TO BE FIXED IN ONE OF SAID BODIES ADJACENT A SURFACE OF THE OTHER BODY SUCH THAT RELATIVE MOVEMENT OF THE BODIES ALTERING SAID CLEARANCE ALTERS THE EFFECTIVE AREA OF THE FIRST OUTLET, A THIRD OUTLET THROUGH WHICH PRESSURE GAS CAN ESCAPE FROM THE OTHER CHAMBER, AND MEANS WHICH IS CONNECTED TO MOVE WITH THE PRESSURE SENSITIVE ELEMET AND WHICH WHEN SO MOVED VARIES THE EFFECTIVE AREAS OF THE SECOND AND THIRD OUTLETS IN THE SAME SENSE AS THE CAUSAL VARIATION OF THE EFFECTIVE AREA OF THE FIRST OUTLET, AND A VALVE TO WHICH THE ELEMENT IS COUPLED FOR VARYING THE OPERATING PRESSURES IN THE TWO ZONES IN RELATION TO EACH OTHER IN A SENSE TO MAINTAIN THE CLEARANCE AT SAID PREDETERMINED VALUE, VARIATION OF THE CLEARANCE IN EITHER SENSE ROM SAID PREDETERMINED VALUE PRODUCING A CORRESPONDING VARIATION IN THE EFFECTIVE AREA OF THE FIRST OUTLET WHICH ACTS TO MOVE THE ELEMENT TO OPERATE THE VALVE, THE SIZES OF SAID ORIFICES AND OUTLETS IN RELATION TO EACH OTHER AND THE OPERATION OF THE MEANS FOR VARYING THE EFFECTIVE AREAS OF THE SECOND AND THIRD OUTLETS BEING SUCH THAT THE OPPOSING FORCES, ON THE ELEMENT ARE EQUAL ONLY WHEN THE CLEARANCE HAS SAID PREDETERMINED VALUE AND THAT, UNDER STEADY CONDITIONS, THE FORCES ON THE ELEMENT ARE BALANCED WHEN THE CLEARANCE HAS SAID PREDETERMINED VALUE WHATEVER THE POSITION OF THE ELEMENT.