JPS5519952A - Means for increasing fuel supplied to carburetor at the time of start - Google Patents

Abstract

PURPOSE: To improve the starting property and stability immediately after the start by increasing the supplied air-fuel mixture only at the time of the start of the engine.

CONSTITUTION: An intake passage (a) is provided with an air passage 3, which bypasses a throttle valve 1 and communicates the upstream side of a choke valve 2 and the downstream side of the throttle valve 1. The passage 3 serves as a means for temporarily increasing intake air. At the time of the start, at which time a normally open valve 5 is held in its open state, air within the intake passage (a) is supplied as replenishment air through the air passage 3 to the downstream side of the throttle valve 1 by a starting operation such as kicking a pedal. Since the air- to-fuel ratio of the air-fuel mixture supplied to the engine is set to be thicker than the theoretical air-fuel mixture, the quantity of intake airwithdrawn into the engine, i.e., air-fuel mixture supplied, is increased to increase power produced from the engine. After the start, the intake negative pressure is coupled through the passage 13 to an operating chamber to close the normally open valve 5 so as to close the air passage 3, thus stopping the replenishment of air.

COPYRIGHT: (C)1980,JPO&Japio