Sundstrand Corporation

John Edward Cygnor

Jeff Clark Miller

Shin Katsumata

Duane C Mosure

Terry L Whitesel

John H Hallman

A fuel pressurization and pumping system for use in a turbine powered aircraft or the like makes use of the advantages of centrifugal pumps, even in a high pressure mode and includes a centrifugal volute pump (24) having a fuel inlet (28) and fuel outlet (32) along with a regenerative pump (34) having a fuel inlet (36) and a fuel outlet (38). The fuel outlet (32) of the centrifugal volute pump (24) is connected to the fuel inlet (36) of the regenerative pump (34) and a valve (50) is provided for blocking flow from the centrifugal volute pump (24) to the regenerative pump (34). A first pressure regulator (56) is connected to regenerative pump outlet (38) for maintaining pressure thereat at a relatively low elevated level and a second pressure regulator (130) is connected to the regenerative pump outlet (38) for maintaining pressure thereat at a relatively high elevated level. A valve system (66), (90) is provided for selectively disabling the first pressure regulator (56).

Aircraft fuel pump with centrifugal pump and regenerative pump stages

Difficulties in adapting centrifugal pumps for use as fuel pumps for turbine powered aircraft are avoided in a system including a centrifugal volute pump (22) on a common shaft (18) with a regenerative pump (24). A pressure responsive throttling valve (46) is connected to the inlet (50) of the regenerative pump (24) so as to cause the regenerative pump (24) to provide fuel at a desired, substantially constant pressure while a check valve (80) is connected to the outlet (72) of the centrifugal volute pump (22) to allow flow from the volute (72) but not the reverse. The outlet side of the check valve (80) can also be selectively connected to the outlet (84) of the regenerative pump (24) so that when the pumps are rotating relatively slowly, the regenerative pump (24) will pump fuel at the desired, substantially constant pressure and, as rotational speed increases, the check valve (80) will open when the centrifugal volute pump (22) is pumping fuel at or about the desired substantially constant pressure.

Aircraft pump system with internal pressure control, comprising a

The weight and volume of a centrifugal fuel pump ideally suited for use in a fuel system for a turbine engine (12) may be reduced in a construction including a single shaft (10) mounting an inducing impeller (18), an impeller (22) for a regenerative pump, and an impeller (24) for a centrifugal volute pump. Hydrostatic bearings (26), (28) journal the shaft (10) within a pump housing (14) and are provided with fuel under pressure via a conduit (30) connected to the outlets of the regenerative pump and the centrifugal volute pump defined by the impellers (22) and (24), respectively.

High speed self-lubricated fuel pump with hydrostatic bearings

A regenerative pump which has a controlled output by having movable lateral channel arcuate slots (36, 38) in channel plates (26) which are on opposite sides of a bladed rotor (18). The channel plates (26) are mounted for sliding movement to reduce the effective vortex channel length in a range from about 325.degree. to about 40.degree.. This will result in a proportional reduction of pump pressure rise and input power requirements. The position of the channel plates may be varied by a servo system that responds to a desired system output performance such as pressure rise or flow delivery rate.

Controlled vortex regenerative pump

The use of a single main centrifugal fuel pump for supplying fuel to an aircraft gas turbine engine has advantages over other known systems, however a problem has existed in that the centrifugal pump, when driven in a fixed ratio to the engine speed, cannot deliver fuel at adequate pressure under engine starting conditions. The disclosed fuel supply system using a main centrifugal pump overcomes this shortcoming by having a turbine-driven start pump added to the fuel supply system with both the turbine and the start pump receiving fuel pumped by the main centrifugal pump and the turbine utilizing the high flow, low pressure fuel to drive the start pump which increases the pressure of the fuel to a value adequate for engine starting. The start pump delivers fuel until such time as the main centrifugal fuel pump has reached a speed to provide the fuel to the engine at the required pressure, at which time the turbine is no longer driven and the output of the start pump goes to zero.

Fluid supply system with turbine driven start pump

The use of a single main centrifugal fuel pump for supplying fuel to an aircraft gas turbine engine has advantages over other known systems, however a problem has existed in that the centrifugal pump, when driven in a fixed ratio to the engine speed, cannot deliver fuel at adequate pressure under engine starting conditions. The disclosed fuel supply system using a main centrifugal pump overcomes this shortcoming by having a turbine-driven start pump added to the fuel supply with both the turbine and the start pump receiving fuel pumped by the main centrifugal pump and the turbine utiliziing the high flow, low pressure fuel to drive the start pump which incresases the pressure of the fuel to a value adequate for engine starting. The start pump delivers fuel until such time as the main centrifugal fuel pump has reached a speed to provide the fuel to the engine at the required pressure, at which time the turbine is no longer driven and the output of the start pump goes to zero.

Fuel supply system with turbine driven start pump

A lubrication scavenge system for an engine bearing compartment or the like utilizing a gear pump with two or more independent inlets with separate flow paths through the pump. The inlets and flow paths are maintained separate from each other by the use of inlet and discharge seal arcs to avoid any fluid communication therebetween. The pump can operate to pump different fluids through each inlet with the fluid being either a gas or liquid or a mixture of both and with the pump continuing its pumping action when there is an instantaneous interchange in the fluid being pumped at each inlet as can occur when the engine bearing compartment is subjected to varying positive and negative gravity forces.

Lubrication scavenge system

This invention relates to a fully modulatable centrifugal pump capable of handling a fluid containing solid contaminant particles and minimizing the temperature rise of the pumped fluid. The pump is of the type that includes an impeller to propel the fluid through a radial outlet to a diffuser which includes a plurality of diffuser passages. The improvement is comprised of the following cooperative combination which includes rotatably mounted valve elements passing, in part, through the diffuser and across the diffuser passages. Each of the valve elements have a port therethrough to variably selectively allow fluid passage therethrough upon rotation of the valve element. A driving arrangement is coupled to each of the valve elements to thereby affect a yieldable rotation of the valve elements in one direction to progressively reduce the opening of the valve element port to the diffuser passage. The aforementioned driving arrangement is also drivingly coupled to the valve elements to provide a direct mechanical coupling to the valve element to thereby affect a nonyieldable rotation of the valve element in an opposite direction to increase the opening of the valve port to the diffuser passage, to thereby ensure that contaminant particles that lodge between a portion of said valve port and the diffuser passage and interrupt movement of one or more valve element port closings do not prevent the remaining valve port elements from closing. During the opposite rotation of the valve elements there is a direct mechanical drive that ensures the opening of the valve port to thereby release the contaminant particle and allow passage of the particle from the valve element and the diffuser.

Growing community of inventors

Rockford, IL, United States of America

John Edward Cygnor