Abstract: A fuel system including a fuel pump for supplying fuel from a source through a variable orifice flow metering valve and then through a variable orifice pressurizing valve to an engine utilizes a determination of the pressurizing valve orifice area to ascertain the fuel flow through the pressurizing valve. The pressurizing valve includes a movable piston with a piston section movable linearly to open and close selectively an orifice. The pressurizing valve may take the form of a cylindrical cavity with the piston reciprocable therein. The cavity is provided with an Inlet port and at least one sidewall outlet port and the piston section slidable along the sidewall outlet port to increase and decrease selectively the effective size of the orifice. A transducer is coupled to the piston to provide an indication of piston position. A second piston section for opening and closing selectively a second orifice may be provided.

Abstract: A fluid flow control device of the type having a spool valve mechanically biased toward a neutral position, a movable fluidic control such as a jet pipe for selectively moving the spool valve from its neutral position, a torque motor movable from a neutral position in response to a driving signal for positioning the fluidic control, a sensor for sensing the position of the spool and providing an output signal indicative thereof, and electronic control circuitry including a feedback circuit which utilizes the sensor signal to selectively modify the torque motor driving signal includes a second feedback arrangement which responds to the position of the fluidic control to modify the spool position. The second feedback arrangement may take the form a resilient mechanical coupling between the spool and the fluidic control and is operable independently of the sensor and feedback circuit.

Abstract: Fluidic control of a number of remote functions is achieved by a single servo controlled linearly actuated distribution valve (29) in conjunction with a like number of bistable hydraulically actuable holding relays (17,19,21) the individual states of which are controlled by the distribution valve. Each holding relay supplies one of two pneumatic signals to an associated remote device (11,13,15). Holding relay or distribution valve motion is only required when a change in a remote function is required. The distribution valve is also adapted to provide a fail-safe signal (79) to all remote devices simultaneously to set the individual remote functions to a desired safe condition.

Abstract: A closure member for sealing an opening for a cavity in a housing to prevent fluid from being communicated to the surrounding environment. The closure member has a shaft with an end member having a irregular radial surface thereon. A first torque is applied to the irregular surface to move threads into corresponding threads in the housing to join the closure member to the housing. A self locking fastener has as stem with threads that extend from a head that engages the housing when a second torque is applied to the head. A washer retained on the stem engages the irregular surface and deforms as the second torque is applied to the head. The deformation prevents relative rotation to thereafter occur between the closure member and housing to assure that the opening in the cavity remains sealed.

Abstract: A control system 30 for measuring the clearance "x" between the tip 26 of a blade 24 and wall 28 in a turbine engine8. A series of probes 32, 32' and 32.sup.N located in the wall 28 each have a reference orifice 52 and a sensing orifice 54. Fluid from a source flows through the reference orifices 52 into the turbine engine. This fluid flow is substantially unrestricted and as a result a fluid pressure P.sub.2 is established in a reference chamber 44. Fluid flow from the sensing orifice 54 is restricted by the relationship of the tip 26 of each blade 24 and as a result fluid pressure P.sub.2 ' is created in chamber 48. A multiplexer 62 sequentially provides transducer 92 and 94 with fluid pressure P.sub.2 from the reference chamber 44 and P.sub.2 ' from sensing chamber 48. The transducers 92 and 94 convert the pneumatic signals into electrical signals which are supplied to a computer 116.

Abstract: In a turbine engine (8) having a shaft (60) with turbine blades (24, 24', . . . 24.sup.N) thereon which rotate in a chamber (12) of the engine housing (10) to produce thrust in response to an operator input. A pneumatic sensor system (30) connected to said housing (10) for maintaining the space relationship between the tip (26, 26', . . . 26.sup.N) of the blades (24, 24', . . . 24.sup.N) and the wall (28) of housing 10 within set limits under varying operational conditions experienced by the turbine engine (8).

Abstract: A system for cooling the bearings supporting the shaft of a rotor in a pneumatic motor powered with hot pressurized fluid. The rotor responds to the flow of hot fluid under pressure by moving to develop output power. The rotors which conduct heat from the hot fluid through the shaft and into the bearings have a series of peripheral axial slots adjacent the ends of the shaft. Fasteners engage the shaft to position the bearings over the series of axial slots. A manifold connects the slots to a discharge conduit. Some of the hot pressurized fluid is diverted through a nozzle in the discharge conduit to create a pressure differential between the manifold and the surrounding environment. This pressure differential draws air from the surrounding environment through the slots and into the manifold. The air on flowing through the slots absorbs heat from the shaft and the inside of the bearings to thereafter maintain the temperature of the bearing below the hot fluid.