Patents Assigned to Walbro Corporation
  • Patent number: 6009859
    Abstract: A fuel system for a fuel injected internal combustion engine has a liquid-cooled fuel pump which draws fuel from a liquid-vapor separator and delivers it under pressure to the engine at a rate higher than that necessary to operate the engine. Preferably, a fuel pressure regulator downstream of the fuel pump and adjacent the engine bypasses excess fuel to a return fuel chamber in communication with the liquid-cooled fuel pump to cool the return fuel before it is returned to the liquid-vapor separator. Reducing the temperature of the returned fuel before it is discharged into the liquid-vapor separator reduces the generation of vapor in the liquid-vapor separator thereby enabling use of a smaller, less expensive vapor separator. Reducing the amount of fuel vapor in the system is desirable because the fuel vapor can decrease the efficiency and life of the fuel pump and is environmentally hazardous.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: January 4, 2000
    Assignee: Walbro Corporation
    Inventors: Ronald H. Roche, Mark S. Swanson
  • Patent number: 6003845
    Abstract: A fuel mixture adjusting and limiting device for a carburetor has a body received in a bore of the carburetor and defining a fuel passage through which liquid fuel is supplied to the high and/or low speed system of the carburetor, an inlet opening in the body through which fuel enters the fuel passage from a metering chamber of the carburetor and a metering pin slidably carried by the body and capable of at least partially restricting the flow of fuel through the inlet opening to control the flow rate of fuel through the body. An adjustment screw threadably received in the bore of the carburetor is rotatable to axially displace the adjustment screw and during at least a portion of the axial range of movement of the adjustment screw, the adjustment screw bears on the metering pin to axially displace the metering pin and thereby control the flow area of the inlet opening.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: December 21, 1999
    Assignee: Walbro Corporation
    Inventor: Dale P. Kus
  • Patent number: 6000426
    Abstract: A system to collect and control the flow of fuel vapor within a vehicle fuel system. In one embodiment, a vapor control unit mounted in the fuel tank permits fuel vapor to be drawn into a tank fill pipe when liquid fuel is being added to the fuel tank to condense at least a portion of the fuel vapor. In a second embodiment a diaphragm actuated valve permits fuel vapor flow from the fuel tank into the tank fill pipe when liquid fuel is being added to the tank to condense at least a portion of the fuel vapor. By condensing the fuel vapor the system reduces the total amount of fuel vapor within the fuel system while preventing the escape of fuel vapor which is hazardous to the environment.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: December 14, 1999
    Assignee: Walbro Corporation
    Inventors: Charles H. Tuckey, Billy R. Blackwell, Lawrence E. Egle
  • Patent number: 6000683
    Abstract: A control mechanism for a carburetor having a throttle valve and a choke valve each having at least a cold-starting position and a full-speed position. The throttle valve is spring biased toward its third, low idle position, and the choke valve is spring biased toward its full-speed open position. When the choke valve is moved from its open position toward its cold start closed position a fast idle lever associated with the choke valve engages, via releasable latch parts, another lever associated with the throttle valve. The interengaging latch parts of these levers hold both valves in their respective cold-starting positions in opposition to the biasing springs. These latch levers can be released by operator actuation of the throttle valve control, thereby causing the choke valve to be automatically returned to its open position by its biasing spring, or, alternatively, the choke valve can be moved independently to its full-speed position.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: December 14, 1999
    Assignee: Walbro Corporation
    Inventor: James E. Van Allen
  • Patent number: 5997262
    Abstract: 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.
    Type: Grant
    Filed: April 10, 1997
    Date of Patent: December 7, 1999
    Assignee: Walbro Corporation
    Inventors: Steven P. Finkbeiner, Kirk D. Fournier, George E. Maroney, Glenn A. Moss
  • Patent number: 5984281
    Abstract: Improvement in peanut clip limiter cap holder, wherein the clip spring legs are interconnected by a spring web that flexes to accommodate flexing of the clip legs free ends during insertion of the associated limiter caps into the retaining clip, and prolongs the effective friction grip service life of the clip. Optional detent dimples on the clip spring legs and cooperative limiter cap grooves enhance yieldable retention of the caps in the clip and the clip on the needle valves. When the peanut clip is used to install only a single limiter cap on a single needle valve, a dummy stud is mounted to the carburetor in the vacant needle valve position and the stud head occupies the vacant limiter cap position in the clip. An improved needle valve is made as an assembly of a lathe-turned tip/shank part and a separate precision die cast head part.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: November 16, 1999
    Assignee: Walbro Corporation
    Inventors: David D. Hacker, Eric L. King, George M. Pattullo
  • Patent number: 5980221
    Abstract: An electric motor and a fuel pump are received within a circumferentially continuous cylindrical shell formed of a somewhat flexible and substantially resilient plastic material to at least partially absorb and reduce the dynamic fuel pressure pulses produced by the fuel pump. The plastic material of the shell tends to flex slightly when acted upon by the dynamic fuel pressure pulses produced by the operating fuel pump to absorb the pressure pulses and reduce their magnitude. Reducing the magnitude of the pressure pulses reduces the noise of the operating fuel pump and helps to achieve a smoother and more pulse free flow of fuel out of the fuel pump assembly outlet. The plastic shell material also reduces vibrations of the fuel pump module to reduce wear on the module and further decrease the noise of the fuel pump in use.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: November 9, 1999
    Assignee: Walbro Corporation
    Inventor: Bradley L. Uffelman
  • Patent number: 5979485
    Abstract: A fuel delivery system for vehicles with more than one fuel tank or a single tank with separate sections under at least some fuel level conditions. The system has an electric fuel pump disposed in the fuel container and a jet pump connected to the electric fuel pump with fuel pickups connected to the jet pump through a siphon. The electric fuel pump powers the jet pump to fill the siphon with liquid fuel and draw fuel through the pickups which are spaced apart in separate sections of the fuel container. When the siphon is completely filled with liquid fuel and the jet pump is operating, any difference in the heads or fuel levels in the sections of the fuel container will cause fuel to flow through the siphon from the section with the greater head to the other section of the tank. This flow, due to the difference in pressure associated with different fuel levels, continues until the fuel levels and, hence, the pressures are substantially the same in each section of the container.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: November 9, 1999
    Assignee: Walbro Corporation
    Inventors: Charles H. Tuckey, G. Clarke Oberheide
  • Patent number: 5979412
    Abstract: A drive circuit for energizing an engine fuel injector coil from a power source which has energy storage means responsive to a first control signal for selectively storing energy from the power source, and means responsive to a second control signal for selectively discharging energy stored in the energy storage means into said injector coil. The stored energy is discharged into the injector coil in addition to energy from the power source, to more rapidly open the fuel injector. In a preferred embodiment, the circuit has an inductor in circuit with the fuel injector, an inductor driver switch to control the flow of current through the inductor and an injector driver switch to control the flow of current through the fuel injector.
    Type: Grant
    Filed: August 12, 1997
    Date of Patent: November 9, 1999
    Assignee: Walbro Corporation
    Inventor: Matthew L. Werner
  • Patent number: 5975061
    Abstract: A bypass fuel pressure regulator disposed downstream of and in communication with a fuel pump outlet to bypass at least a portion of the outlet fuel from the fuel pump corresponding to the engine's fuel demand. The regulator has a bypass passage with an inlet in communication with the fuel pump outlet and an outlet in communication with the fuel tank. A valve assembly is received in and controls the flow of fuel through the bypass passage. The valve assembly has a disc carried on one end of a stem which has an enlarged valve head adjacent its other end which is movable to open and close an outlet opening of the regulator. The disc is disposed generally transverse to the axis of the bypass passage and upstream of the valve head. The disc has at least one and preferably several openings through which fuel flows into the bypass passage through the disc. A spring is received between the regulator body and the disc to yieldably bias the valve head onto a valve seat to close the regulator outlet.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: November 2, 1999
    Assignee: Walbro Corporation
    Inventors: Paul F. Briggs, George H. Bucci
  • Patent number: 5960775
    Abstract: A fuel pump module disposed within a vehicle fuel tank has a fuel pump therein to draw fuel from the fuel tank and deliver that fuel under pressure to the vehicle engine, and a jet pump driven by the fuel pump to lower the pressure within the module to draw fuel from the fuel tank through a filtered inlet of the module when the fuel pump is operating. When the fuel pump is not operating, such as when the vehicle is not in use, the jet pump ceases to operate and the pressure within the module returns to that of the fuel tank. When the level of fuel in the fuel tank is lower than that within the fuel pump module and the pump is turned off, a portion of the fuel within the module returns to the fuel tank through the filtered inlet of the module thereby dislodging at least some of the contaminants trapped by the filter.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: October 5, 1999
    Assignee: Walbro Corporation
    Inventor: Charles H. Tuckey
  • Patent number: 5962946
    Abstract: A flat commutator for an electric motor of a vehicle fuel pump. The commutator, is made with a one-piece carbon ring having a flat outer face, a one-piece conductor ring underlying the outer face of and embedded in the carbon ring, and a housing of a plastic insulating material molded on the rear face and the inner and outer edges of the carbon ring and adapted to mount the commutator on a motor armature. A plurality of circumferentially spaced apart grooves extend radially and axially completely through both the carbon ring and the conductor ring to provide a plurality of individual sintered carbon segments each with a separate conductor for electrically connecting the segments with armature coils.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: October 5, 1999
    Assignee: Walbro Corporation
    Inventors: Richard L. Kobman, Michael L. Mercer, Dirk G. Westendorf, Arthur J. Birchenough, James A. George, Marc B. Ruprecht, J. D. Tuckey, deceased
  • Patent number: 5960817
    Abstract: A vehicle on board system for recovering fuel vapors from the fuel tank both during filling of the fuel tank with volatile hydrocarbon liquid fuel and operation of the vehicle engine. A control unit in the fuel tank has a valve assembly actuated by a float to control the flow of fuel vapors from the top of the tank into a receiving canister with activated charcoal for absorbing the fuel vapors which can be purged from the canister by operation of the engine. The valve assembly has a valve seat, a flexible elastomeric closure received on a pivotally mounted carrier plate movable to open and closed positions relative to the seat, and a stripper plate encompassing the seat, overlying the closure and pivotally movable by the float to disengage the closure from the seat to open the valve.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: October 5, 1999
    Assignee: Walbro Corporation
    Inventors: Mark R. Johansen, Timothy P. Neal, Jason J. St. Pierre
  • Patent number: 5947153
    Abstract: An improved filler neck for a fuel inlet of a vehicle fuel tank has a bend communicating with converging and diverging portions which control the flow of fuel through the filler neck to ensure that fuel flows through and downstream of the bend without backing up in the filler neck and actuating an automatic shutoff device of a refueling nozzle received in the filler neck. The filler neck also preferably has a bypass fuel passage through which fuel flows upstream through the filler neck and out to the atmosphere if a predetermined maximum pressure is exceeded within the fuel tank to limit the maximum pressure within the fuel tank and prevent it from being damaged or rupturing. Several angled ribs in the filler neck housing guide the refueling nozzle for proper positioning within the filler neck. Other ribs also provide gaps between the refueling nozzle and the filler neck housing to prevent the refueling nozzle from sealing the filler neck inlet.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: September 7, 1999
    Assignee: Walbro Corporation
    Inventors: George H. Bucci, Mark R. Johansen, Timothy P. Neal
  • Patent number: 5925962
    Abstract: A flat commutator for an electric motor of a vehicle fuel pump. The commutator, is made with a one-piece carbon ring having a flat outer face, a one-piece conductor ring underlying the outer face of and embedded in the carbon ring, and a housing of a plastic insulating material molded on the rear face and the inner and outer edges of the carbon ring and adapted to mount the commutator on a motor armature. A plurality of circumferentially spaced apart grooves extend radially and axially completely through both the carbon ring and the conductor ring to provide a plurality of individual sintered carbon segments each with a separate conductor for electrically connecting the segments with armature coils.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: July 20, 1999
    Assignee: Walbro Corporation
    Inventors: Richard L. Kobman, Michael L. Mercer, Dirk G. Westendorf, Arthur J. Birchenough, James A. George, Marc B. Ruprecht, J. D. Tuckey, deceased
  • Patent number: 5905423
    Abstract: A permanent magnet armature solenoid has a tip formed of a non-magnetic material operably connected to a ferromagnetic insert which is firmly held to the end of the magnetic armature by the magnetic attraction between the insert and armature. The magnetic field of the armature holds the armature and the insert together as a single unit, even under high acceleration, deceleration and rapid movement of the armature. The insert is relatively small compared to the armature and the addition of the insert to the solenoid does not significantly adversely affect the performance of the solenoid. The insert is preferably formed of a magnetically susceptible metal such as iron, steel or stainless steel. Desirably, the tip is formed of a polymeric material and preferably of an elastomer so that the tip may be molded directly to the insert by conventional molding techniques to facilitate molding the non-magnetic tip onto the insert.
    Type: Grant
    Filed: December 15, 1997
    Date of Patent: May 18, 1999
    Assignee: Walbro Corporation
    Inventor: Jeffrey C. Hoppe
  • Patent number: 5881698
    Abstract: A fuel pump with an inlet through which fuel is drawn from a fuel tank and an outlet through which fuel is discharged under pressure to an operating engine of a vehicle has an inlet throttle valve actuated by the pressure of the pump outlet fuel to at least partially restrict the flow of fuel through the inlet of the fuel pump and thereby reduce the flow rate of fuel discharged from the fuel pump when the fuel pump is delivering more fuel than is being consumed by the engine. The valve is preferably received within an inlet module between the fuel tank inlet and the fuel pump inlet. Preferably, the valve is slidably received in a passage in the module and actuated by a diaphragm received in the passage and displaceable by the pressure of the pump outlet fuel in response to engine fuel demand.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: March 16, 1999
    Assignee: Walbro Corporation
    Inventors: Charles H. Tuckey, G. Clarke Oberheide
  • Patent number: 5878709
    Abstract: A positive off and automatic on ignition stop switch and electronic circuit for use in an internal combustion engine. The circuit that allows for normal operation of the engine in an unbiased state. When it is desired to turn the engine off, a stop switch is triggered which provides a single mechanism for shutting off the engine. After the switch is activated, the circuit holds the ignition circuit in an off state for a sufficient amount of time to allow the engine to completely stop operation. The circuit holds the engine in the off state for a period of time even after the switch is deactivated. As a result, the operator of a piece of equipment in which the present invention is utilized can activate a switch one time, which results in the engine coming to a complete stop, without the requirement of further activity.
    Type: Grant
    Filed: August 19, 1997
    Date of Patent: March 9, 1999
    Assignee: Walbro Corporation
    Inventors: Martin N. Andersson, Jason R. Koziatek
  • Patent number: 5873349
    Abstract: For a fuel injected combustion engine a fuel pressure regulator having a rapidly and accurately regulated output pressure over a wide range of flow rates by bypassing and returning to a fuel tank a portion of the input fuel from a fuel pump through a bypass valve actuated by a flexible diaphragm. The diaphragm is responsive to the pressure of the input fuel on one side of the diaphragm and a vacuum on the other side of the diaphragm having a magnitude which is varied as a function of the flow rate of the fuel bypassed through the valve and returned to the fuel tank. Preferably, this vacuum is produced by a venturi or orifice through which the bypass fuel flows.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: February 23, 1999
    Assignee: Walbro Corporation
    Inventors: Charles H. Tuckey, G. Clarke Oberheide
  • Patent number: 5866819
    Abstract: A non-destructive method and apparatus for determining the thickness of individual layers of different materials in a multilayer structure particularly useful in analyzing the layers in a multilayer plastic fuel tank, utilizes a constant and relatively high frequency ultrasonic pulse transmitted into the multilayer structure and records the time when interference pulses are received to determine the thickness of the individual layers in the multilayer structure. The interference pulses are generated at the interface between adjacent layers of sufficiently different materials and thus, the time between interference pulses is a function of the amount of time needed for the ultrasonic pulse to pass through a layer of material.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: February 2, 1999
    Assignee: Walbro Corporation
    Inventors: Dan Albu, Salem M. Taboun