Abstract: A fuel metering unit including a pump having a rotor with a plurality of slots. The pump also includes a pivotally movable cam ring coaxially arranged with respect to the rotor. Vanes are slideably disposed in the slots for maintaining contact with the cam ring during movement thereof. A servovalve has a motor and nozzles operatively connected to the pump such that increased flow through the first nozzle pivots the ring of the pump toward maximum while increased flow through the second nozzle pivots the ring toward minimum. An arm extends between the nozzles for varying fluid flow therethrough. The arm couples to the motor such that the motor moves the arm. A flow meter connects to the pump and an end of the arm for applying a force against the arm to assist in maintaining position of the arm.

Abstract: A fuel metering unit including a pump having a rotor with a plurality of slots. The pump also includes a pivotally movable cam ring coaxially arranged with respect to the rotor. Vanes are slideably disposed in the slots for maintaining contact with the cam ring during movement thereof. A servovalve has a motor and nozzles operatively connected to the pump such that increased flow through the first nozzle pivots the ring of the pump toward maximum while increased flow through the second nozzle pivots the ring toward minimum. An arm extends between the nozzles for varying fluid flow therethrough. The arm couples to the motor such that the motor moves the arm. A flow meter connects to the pump and an end of the arm for applying a force against the arm to assist in maintaining position of the arm.

Abstract: A fuel metering unit including a pump having a rotor with a plurality of slots. The pump also includes a pivotally movable cam ring coaxially arranged with respect to the rotor. Vanes are slideably disposed in the slots for maintaining contact with the cam ring during movement thereof. A servovalve has a motor and nozzles operatively connected to the pump such that increased flow through the first nozzle pivots the ring of the pump toward maximum while increased flow through the second nozzle pivots the ring toward minimum. An arm extends between the nozzles for varying fluid flow therethrough. The arm couples to the motor such that the motor moves the arm. A flow meter connects to the pump and an end of the arm for applying a force against the arm to assist in maintaining position of the arm.

Abstract: A fuel pump for use in conjunction with a gas turbine engine is disclosed which includes a pump housing, a shrouded rotor member, and an inlet post member, wherein fluid is axially supplied along the pump centerline and then radially discharged at a first pressure to the interior chamber of the pump housing, at the base portion of vane elements associated with the rotor, thereby contacting the vane elements at a minimum angular velocity and angle of incidence. Also disclosed is a single bearing arrangement for eccentrically supporting a shrouded rotor member.

Abstract: A system is disclosed for draining residual fuel from the engine manifold of a gas turbine which includes an ejector having an inlet port for receiving high pressure fuel from a main fuel pump at engine shut-down, an outlet port and a suction port. The ejector defines a nozzle that extends between the inlet port and the outlet port for increasing the velocity of high pressure fuel flowing therethrough at engine shut-down so as to create suction at the suction port. A motive valve controls the flow of high pressure fuel between the main fuel pump and the inlet port of the ejector. The motive valve is configured for movement between a first position wherein high pressure fuel is directed from the main fuel pump to the engine manifold during engine start-up and operation, and a second position wherein high pressure fuel is directed from the main fuel pump to the inlet port of the ejector at engine shut-down.

Abstract: An adjustable fixed displacement vane pump is disclosed which includes a pump housing defining an interior pumping chamber having a central axis extending therethrough, a rotor member mounted for rotational movement within the interior pumping chamber of the pump housing about an axis aligned with the central axis of the interior pumping chamber, the rotor member having a central vane section with a plurality of circumferentially spaced apart radial vane slots formed therein, each vane slot supporting a corresponding vane element mounted for radial movement therein, and each vane element having an outer tip surface, a cam member mounted for pivotal movement within the interior pumping chamber of the pump housing about a fulcrum axis extending parallel to the central axis of the rotor member, the cam member defining a cam body having a circular bore extending therethrough for receiving the rotor member, the circular bore forming a cam chamber defining a cam surface making continuous contact with the outer tip

Abstract: A vane pump is disclosed for use with gas turbine engines adapted and configured to provide a failure mode similar to that of a traditional gear pump. The vane pump includes a pump housing, a cam member, a cylindrical rotor member and a mechanism for communicating a high pressure fluid from the discharge arc region to the inlet arc region when the tip surface of each vane element has experienced a predetermined amounted of wear so as to prevent pump startup. The wearing of the tip surface of each vane element resulting from the slideable engagement with the circumferential surface of the pumping cavity.

Abstract: A variable displacement vane pump includes a pump housing having a cylindrical interior chamber, a cylindrical rotor member mounted for rotational movement within the interior chamber of the pump housing, a cam member mounted for pivotal movement within the interior chamber of the pump housing about a fulcrum aligned with the vertical centerline of the interior chamber, the cam member defining a cam body having a circular bore extending therethrough for receiving the rotor member, the cam body having lateral sealing lands formed thereon, the sealing lands having arcuate sealing surfaces defining segments of a cam arc through which the cam member pivots, and static cam seals supported within the interior chamber of the pump housing and oriented on each end of a chord of the cam arc, each cam seal biased into a continuous contact position with an adjacent sealing surface of the cam member.

Abstract: A vane pump is disclosed for use with gas turbine engines which has pressurized fluid supplied to the undervane portion of the vane elements to balance the forces imparted thereon. The vane pump includes a pump housing, a cam member, a cylindrical rotor member and a chamber. The chamber is defined within the housing and positioned for fluid communication with the undervane portion of each vane element to provide a desired pressure thereto. The chamber is in fluid communication with a first pressure source and a second pressure source, wherein the first pressure source is associated with the discharge arc segment of the pumping cavity, and the second pressure source is associated with the inlet arc segment of the pumping cavity.

Abstract: A fuel metering unit including a pump having a rotor with a plurality of slots. The pump also includes a pivotally movable cam ring coaxially arranged with respect to the rotor. Vanes are slideably disposed in the slots for maintaining contact with the cam ring during movement thereof. A servovalve has a motor and nozzles operatively connected to the pump such that increased flow through the first nozzle pivots the ring of the pump toward maximum while increased flow through the second nozzle pivots the ring toward minimum. An arm extends between the nozzles for varying fluid flow therethrough. The arm couples to the motor such that the motor moves the arm. A flow meter connects to the pump and an end of the arm for applying a force against the arm to assist in maintaining position of the arm.

Abstract: A fuel pump for use in conjunction with a gas turbine engine is disclosed which includes a pump housing, a shrouded rotor member, and an inlet post member, wherein fluid is axially supplied along the pump centerline and then radially discharged at a first pressure to the interior chamber of the pump housing, at the base portion of vane elements associated with the rotor, thereby contacting the vane elements at a minimum angular velocity and angle of incidence. Also disclosed is a single bearing arrangement for eccentrically supporting a shrouded rotor member.

Abstract: A variable displacement vane pump is disclosed which includes a pump housing having a cylindrical interior chamber, a cylindrical rotor member mounted for rotational movement within the interior chamber of the pump housing, a cam member mounted for pivotal movement within the interior chamber of the pump housing about a fulcrum aligned with the vertical centerline of the interior chamber, the cam member defining a cam body having a circular bore extending therethrough for receiving the rotor member, the cam body having lateral sealing lands formed thereon, the sealing lands having arcuate sealing surfaces defining segments of a cam arc through which the cam member pivots, and static cam seals supported within the interior chamber of the pump housing and oriented on each end of a chord of the cam arc, each cam seal biased into a continuous contact position with an adjacent sealing surface of the cam member.