Idle speed control apparatus in throttle body for single cylinder

Abstract

The invention inhibits a blown-back fuel from flowing into an air screw passage and a starter passage, and a stable engine idling operation is obtained. [Constitution] A single idle air control passage (5) is open toward a suction air passage (2a) in a downstream side from a throttle valve (4), a starter passage (6) and an air screw passage (7) are independently branched from an upstream side passage (5a) of the idle air control passage (5), an upstream side of the starter passage (6) communicates with an atmospheric air, a downstream side thereof communicates with the upstream side passage (5a) of the idle air control passage (5), a start opening and closing valve (10) controlling an opening area of the passage is arranged in the starter passage (6), an upstream side of the air screw passage (7) communicates with an atmospheric air, a downstream side thereof communicates with the upstream side passage (5a) of the idle air control passage (5), and an air screw (11) controlling an opening area of the passage is screwed to the air screw passage.

Dependencies are inferred from the claim text.