Control mechanism for adjustable gas turbine nozzle

Claim 1

AN ARRANGEMENT FOR CONTROLLING THE POSITION OF ADJUSTABLE NOZZLE VANES FOR A POWER TURBINE OF A VEHICLEMOUNTED GAS TURBINE ENGINE, COMPRISING PRESSURE RESPONSIVE MEANS OPERATIVELY CONNECTED TO SAID NOZZLE VANES, ACTUATING MEANS OPERATIVELY CONNECTED TO SAID PRESSURE RESPONSIVE MEANS FOR ACTUATING SAID PRESSURE RESPONSIVE MEANS IN ORDER TO ADJUST THE POSITION MEANS OPERATIVELY CONNOZZLE VANES, MANUALLY POSITIONED MEANS OPERATIVELY CONNECTED TO SAID ACTUATING MEANS FOR TRANSMITTING AN OPERATOR REQUEST SIGNAL THERETO AND POSITIONING SAID ACTUATING MEANS IN ACCORDANCE THEREWITH, SELECTOR VALVE MEANS ADDITIONALLY POSITIONED BY SAID ACTUATING MEANS AND HAVING TWO OPERATING POSITIONS, AND MEANS RESPONSIVE TO POWER TURBINE SPEED FOR AT TIMES ACTUATING SAID PRESSURE RESPONSIVE MEANS, SAID POWER TURBINE SPEED RESPONSIVE MEANS BEING EFFECTIVE WHENEVER THE SPEED OF SAID POWER TURBINE IS GREATER THAN A PREDETERMINED MINIMUM AND SAID MANUAL MEANS IS IN A POSITION CAUSING SAID SELECTOR VALVE MEANS TO BE IN ONE OF SAID TWO OPERATING POSITIONS TO OVERRIDE THE OPERATOR REQUEST SIGNAL TRANSMITTED TO SAID ACTUATING MEANS BY SAID MANUAL MEANS THEREBY CAUSING SAID PRESSURE RESPONSIVE MEANS TO POSITION SAID ADJUSTABLE NOZZLE VANES INTO ONE EXTREME POSITION, SAID POWER TURBINE SPEED RESPONSIVE MEANS BEING INEFFECTIVE TO OVERRIDE THE OPERATOR REQUEST SIGNAL WHENEVER THE SPEED OF SAID POWER TURBINE IS LESS THAN SAID PREDETERMINED MINIMUM OR WHENEVER SAID SELECTOR VALVE MEANS IS IN THE OTHER OF SAID TWO OPERATING POSITIONS.