Air-fuel mixture ratio control device
AssigneeAisan Industry Co., Ltd.
InventorsShigetaka Takada, Kazumichi Naruse
Life of this patent
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Abstract
An air-fuel ratio control device characterized by the fact that an electromagnetic valve which controls the air bleed quantities for both high- and low-speed fuel systems simultaneously has a pin inserted in a valve disc so as to prevent the rotation of the valve disc but allow it to move axially for open-close operation, so that the valve disc and the seat always contact at the same contacting portion and maintain a perfect seal therebetween. This enables an accurate control of the air bleed quantitiy and therefore of the air-fuel ratio.
Claims6
An air-fuel mixture ratio control device for controlling air-fuel mixture ratio in a carburetor which supplies a fuel mixture to an engine and has high speed and low speed systems with air bleed intake ports, comprising
- a feed-back loop including an exhaust gas sensor means for detecting the air-fuel ratio of the fuel mixture,
- the air bleed intake ports of said high speed and low speed fuel systems each being projected forming two air bleed control ports,
- an actuator means for controlling air bleed quantities for both the high speed and low speed fuel systems in the carburetor which supplies the fuel mixture to the engine,
- a control circuit means for driving said actuator means in dependency on a signal from said exhaust gas sensor means,
- said actuator means comprising,
- means comprising a single, rotatable solenoid valve axially moveably mounted with a stroke of the valve for simultaneously opening and closing respectively said air bleed control ports of said high speed and low speed fuel systems, said solenoid valve having an armature, a plate-shaped valve member mounted on said armature and a valve seat portion, said air bleed control ports extending in said valve seat portion,
- a pin means projecting from said valve seat portion operatively engages said plate-shaped valve member over the stroke of said valve, for preventing rotation of said valve member,
- said plate-shaped valve member is substantially rectangular, is centrally connected to said armature and is formed with a U-shaped groove in one narrow edge of said plate-shaped valve member,
- said pin has a free end remote from said valve seat portion and a length from said free end to said valve seat portion slightly greater than the stroke of said valve,
- said pin freely extends into said U-shaped groove from one side and said free end extends beyond the other side of said valve member in at least a postion of the latter against said valve seat portion.
Dependencies are inferred from the claim text.