Walbro Corporation

Kirk D Fournier

Charles H Tuckey

Wayne T Lipinski

George H Bucci

Daniel A Gilmour

Joseph M Ross

David E Mroczka

Glenn A Moss

Ronald B Kuenzli

George Earl Maroney

John F Combest

Steven P Finkbeiner

An electric motor regenerative or turbine type fuel pump has a fuel pumping channel with a cross sectional area which decreases from adjacent its inlet to at least midway through the pumping channel to improve the efficiency and vapor handling capability of the fuel pump. Preferably, the pumping channel generally continuously decreases in cross-sectional area from its inlet to its outlet. In one form, the pumping channel is defined between a pair of plates or caps and a split ring received between the caps and surrounding an impeller having a plurality of vanes formed about its periphery and disposed within the pumping channel. Each of the caps preferably has a groove therein forming a portion of the pumping channel with each of the grooves having a greater cross sectional area adjacent the inlet of the pumping channel compared to the outlet of the pumping channel. In another form, a so-called side channel turbine pump, has a pumping channel defined by a groove in a flat face of a stator and a rotor driven to rotate by the motor has a circumferential array of vanes formed in a flat face and in communication with the pumping channel to develop increasing pressure from the inlet to the outlet of the pumping channel. This pumping channel has a greater depth and hence a greater cross sectional area adjacent its inlet as compared to its outlet.

Tapered channel turbine fuel pump

An in-tank type electric motor fuel pump with a fuel inlet end cap, a fuel outlet cap, a case coaxially joining the end caps to form a pump housing, an electric motor mounted in the housing having a stator with spring-retained permanent field magnets surrounding the motor armature, and a gerotor pump in the housing rotatably driven by the motor armature. An inlet port plate, an outlet port plate and a cam ring sandwiched between the plates form a gerotor pocket axially between the plates, and inner and outer gear rotors are disposed in the pocket with intermeshing teeth defining circumferentially disposed expanding and ensmalling pumping chambers. A pair of alignment and fastening screw pins are the sole hardware for clamping the plates and cam ring in tightly sandwiched relationship and holding the pump unit together in properly axially, radially and angularly oriented component relationship in precision final assembly as an operable gerotor pump. The screw pins each have a cylindrical smooth surface shank portion precision fitting in smooth wall precision aligned bores in the plates and cam ring. The screw pin threaded end threadably engages a threaded portion of the inlet plate bore hole that is slightly reduced in diameter relative to the smooth surface bore holes. The radial tolerances between the pin and inlet plate hole threads are larger than that between the pin shank smooth portion and the associated smooth surface alignment bores in the plates and cam ring to prevent alignment distortion from thread seating stresses. The screw pins also have axially elongated and slotted screw heads that serve as fail-safe stops limiting loosening motion of the magnets. The pump rotors have predetermined fixed assembly axial and radial clearance dimensions relative to the pump plates and cam ring respectively established and maintained in assembly by the screw pins fitment in the plates and cam ring.

Screw pins for a gear rotor fuel pump assembly

An engine fuel delivery system and method, and for use therein, an in-tank fuel pump and reservoir canister module assembly having a primary fuel filter mounted in a base subassembly adjacent the bottom of the tank and defining a filter chamber in the base having an outlet connected to the inlet of an electric fuel pump received directly in the tank exteriorly alongside of an upright open top reserve fuel canister. The pump outlet is connected to a bypass pressure regulator which discharges fuel in excess of engine demand into the canister. The canister has a bottom outlet mounted on the base subassembly and closed by a flow controlling valve and/or by a restricted orifice communicating the canister outlet with the filter chamber for returning bypassed reserve fuel from the canister reservoir to the pump inlet, either continuously and/or when a low level supply of fuel in the tank to the primary filter is interrupted, such as during cornering or going up or down a steep hill or incline. The valve is formed integrally on or mounted in contact with a secondary filter diaphragm base mounted between the canister outlet and filter chamber and also communicating with the tank. The valve opens with canister outflow downwardly against the bias of a coil spring in response to pump suction acting on a capillary seal formed on the diaphragm filter material to thereby allow reserve fuel to wash over and flow through it into the filter chamber. At system shut-down a filter backwash flow can occur from the canister reservoir.

In-tank fuel pump and reservoir

An in-tank fuel pump and reservoir canister module having a fuel filter mounted in the module base adjacent the bottom of the tank and defining a filter chamber having an outlet connected to the inlet of an electric fuel pump received directly in the tank exteriorly alongside of an upright overflow-type reserve fuel canister. A canister bottom outlet is closed by a flow controlling valve and/or by an always-open restricted orifice communicating with the filter chamber for returning engine bypassed reserve fuel from the canister reservoir to the pump inlet, either continuously and/or only when a low level supply of fuel in the tank to the filter is interrupted. The valve is operated by a diaphragm portion of the filter, base-mounted between the canister outlet and filter chamber and also communicating directly with the tank, the valve opening against the bias of a coil spring in response to pump suction acting on a capillary seal formed on the diaphragm filter to thereby allow reserve fuel to flow into the filter chamber. At system shut-down a filter backwash flow can occur from the canister reservoir. The pump rotary vane impeller chamber has an internal vapor purging passageway communicating at its outlet directly with the interior of the tank so as not to be subjected to any anti-purging gravity pressure head differential existing between the fuel level in the canister reservoir versus that of the main body of fuel in the tank.

An electric fuel pump and valve-controlled canister reservoir assembly mounted directly in a vehicle fuel tank with a pump main fuel inlet connected with a primary fuel filter disposed in the bottom of the tank. A pump fuel outlet supplies fuel for a vehicle engine and communicates through an engine bypass system with the canister reservoir to accumulate a reserve supply of fuel. The reservoir canister communicates with the pump inlet through a secondary filter and an inertia/gravity-activated valve module having a free rolling activator ball and associated can-like valve member cooperative with a large diameter annular valve seat to provide a sensitive valve with a large flow controlling cross-sectional area. The valve module thus provides an auxiliary supply of fuel to the pump inlet, preferably in bypass flow relation to the primary in-tank filter, and at a high flow rate when there is an interruption of fuel from the tank to the primary filter caused by adverse vehicle motion and/or orientation. The reservoir canister also may include an upright standpipe having an upper inlet opening at an elevation somewhat below the open top of the canister. The lower end of the standpipe opens to the valve chamber of the module to admit fuel to the pump inlet in bypass, always-open, flow relation with the module valve member and also in bypass flow relation to the primary filter.

In a fuel system for an internal combustion engine powering a motor vehicle, a fuel reservoir canister mounted in a main fuel tank. An annular fuel filter element is enclosed in an axially elongate housing with radially spaced apart inner and outer cylindrical side walls. The housing is received in the canister with its outer side wall bearing on and radially supported by a complementary side wall of the canister. Preferably, a fuel pump and pressure regulator are disposed in the canister preferably so they overlap with and are encircled by the filter housing. The high pressure outlet of the fuel pump is connected to the filter to supply filtered fuel to the engine at a pressure regulated and controlled by the pressure regulator.

High capacity fuel pump and filter combination

A gear rotor fuel pump having a gear rotor pump assembly received on a cantilever bearing in an end cap of the pump and an armature journalled for rotation at one end in the bearing while being rotatably unsupported at its other end for preventing bearing misalignment and reducing pump noise. The end cap preferably carries a bellows modulator for reducing pump noise by reducing the amplitude of fuel pressure pulses transmitted to the bellows from the pump assembly through a port in the end cap. To further reduce noise, the end cap preferably has at least one cavity for receiving compressible gas therein to further absorb the pressure pulses as well as noise generated by turbulent fuel flow at a pump inlet. Preferably, the end cap has an interior locator surface which abuts the pump assembly and a locator groove which are both preferably machined relative to the bearing axis so that the pump assembly and armature are accurately axially and radially located in the pump to reduce pump noise while increasing performance, reliability, accuracy and repeatability in the mass production of the pump.

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Essexville, MI, United States of America

Kirk D Fournier