Walbro Corporation

Walbro Engine Management, L.l.c.

Walbro Japan, Inc.

Takashi Horikawa

Jun Takano

Takashi Abei

Tomoya Kawada

Katsuaki Hamataka

Teruhiko Tobinai

Dairoku Suzuki

Shinichi Ohgane

Takeshi Sakaguchi

Katsushi Habu

Hiraku Watanabe

Hiroaki Ishii

Kazunori Tsubakino

Shunya Nakamura

Makoto Waku

Kazuhito Fujisawa

Taketoshi Hirama

Nobuyuki Kuroki

Hironari Ikeda

Susumu Takezawa

In at least some implementations, a fuel metering valve, includes a bobbin defining a passage and having one or more voids in the surface of the bobbin that defines the passage, aa wire coil around the bobbin and an armature. The armature is received within the passage in the bobbin and movable relative to the bobbin from a first position to a second position when electricity is supplied to the wire coil.

Fuel and air charge forming device

In at least some implementations, a charge forming device for a combustion engine includes a throttle body and a throttle valve. The throttle body has a throttle bore with an inlet through which air flows into the throttle bore and an outlet from which a fuel and air mixture exits the throttle bore. The throttle bore has a throat between the inlet and outlet and the throat has a reduced flow area compared to at least one of the inlet and outlet. The throttle valve has a valve head received within the throat of the throttle bore and movable relative to the throttle body between a first position and a second position wherein the flow area between the valve head and the throttle body is greater when the valve head is in the second position than in the first position.

In at least some implementations, a charge forming system for a combustion engine includes a first fuel supply device having a first passage from which fuel is discharged for delivery to the engine and a second fuel supply device having a second passage from which fuel is discharged for delivery to the engine. The first passage communicates with the second passage so that the fuel in the first passage is combined with the fuel in the second passage.

Charge forming system for combustion engine

A fuel control device for a combustion engine capable of running on any one of a plurality of fuels has a fuel selection module with a plurality of fuel type settings for selecting a specific fuel type whereupon the fuel control device controls the outlet pressure of the chosen fuel to a desired fuel pressure corresponding to the calorific properties of the chosen fuel. The fuel selection module preferably operates a plurality of fuel flow circuits each designated for a specific fuel type, and each having a biased closed inlet valve and a biased closed outlet valve. Located preferably between each inlet and outlet valve is a pressure regulator designated for the specific fuel type and controlling the outlet fuel pressure. The device preferably includes a fuel metering apparatus and a shutoff valve that communicate with, and control in part, fuel flow through the fuel flow circuits.

Multi-gaseous fuel control device for a combustion engine with a carburetor

A versatile rotary carburetor has an idle adjustment needle, a high speed adjustment needle, and preferably an air bypass screw which are substantially parallel to one another and are axially exposed for adjustment in a substantially common direction. Preferably a cammed rotary throttle valve is seated in a body of the carburetor for rotation about and axial movement along an axis. The rotary throttle valve intersects a mixing passage in the body, and carries a through-bore that variably generally aligns to the mixing passage upon rotation of the throttle valve. The throttle valve projects axially through an external surface of the body and threadably receives the idle adjustment needle oriented concentrically to the axis. A primary fuel feed tube disposed concentrically to the axis projects into the through-bore to receive the idle adjustment needle at an open distal end which variably obstructs an orifice in a cylindrical wall of the tube that generally communicates with the through-bore for delivering liquid fuel to the mixing passage. The high speed adjustment needle is preferably threaded to the body for adjustably intersecting and obstructing a fuel passage in the body that flows liquid fuel to the fuel feed tube for the flow of liquid fuel. Preferably, the air bypass screw threads into the body for adjustably intersecting and obstructing an air bypass passage in the body communicating at both ends with the mixing passage for generally bypassing the rotary throttle valve when in an idle position.

Rotary carburetor

A rotary throttle valve carburetor includes a main body defining a mixing passage and a valve bore, and a throttle valve rotatably received in the valve bore to selectively open and close the mixing passage. The carburetor main body includes an integral throttle valve support extending radially inwardly relative to the valve bore adjacent to a first end of the valve bore and a second end of the valve bore is open. A throttle cable retaining portion may also be integrally formed with the carburetor main body.

Rotary throttle valve carburetor

A compact engine start device of a combustion engine rotary-type carburetor overrides normal operation of a rotary throttle valve to provide a richer mixture of fuel-and-air to start a cold engine. Rotation of a start lever of the start device activates a releasable camming interface coupler causing the throttle lever to rotate about a rotary axis and axially lift partially out of the carburetor at prescribed angular and axial distances. This provides the engine, through a fuel-and-air mixing passage, with a controlled and enriched ratio and volume of a fuel-and-air mixture. Preferably, the start lever has a projecting rod that inserts into a hole in the carburetor body for rotation about an axis orientated substantially parallel to the rotary axis. An outward surface of the start lever is in rotational sliding contact with a low-profile, preferably cantilevered, retention arm preferably formed unitarily to a metering fuel pump cover engaged removably to the body of the carburetor, thus allowing rotational movement but preventing axial movement of the start lever. Because the start lever does not move axially to displace the rotary throttle valve, the height of the start lever is favorably minimized. Moreover, the start lever preferably has a knob for user interface at a distal end of the lever that conforms generally about the retention arm thus maximizing knob size yet not contributing to an increase in carburetor size.

Engine start device of a rotary valve carburetor

A starting device for a rotary throttle valve-type carburetor enables adjustment of the quantity of air and fuel delivered to an engine to facilitate the cold start of the engine. The starting device changes the position of the throttle valve prior to starting the engine to adjust the fuel and air mixture delivered to the engine as desired to facilitate starting and initial warming up of the engine.

Growing community of inventors

Natori, Japan

Takashi Horikawa