IDLE AIR CONTROL DEVICE OF FUEL INJECTION DEVICE

摘要

An idle air control device of a fuel injection device, wherein an air valve is driven by a motor. The air valve is accurately disposed concentrically with an air valve guide hole bored in a throttle body to improve the dynamic characteristics of the air valve. The motor (M) is disposed in a motor case (1a), a cylindrical collar (2) is fixedly disposed in an insert tube part (1b) formed integrally with the motor case (1a), and a motor output shaft (Ma) is projectedly disposed in the collar (2). A slider (3) is threaded to the outer periphery of the motor output shaft (Ma), and the air valve (4) is disposed between the outer peripheral part (3f) of the slider (3) and the inner peripheral part (2b) of the collar (2). The slider is formed such that its rotation is suppressed by the collar (2) and its axial movement only is allowed. The air valve (4) is disposed so as to be elastically pressed toward the locking stage part (3g) of the slider (3) by an air valve spring (5). The slider (3) is axially moved according to the rotation of the motor (M), and the air valve (4) is also axially moved in synchronism with the movement of the slider (3) to control the opening of a bypass air passage (54) opening in the air valve guide hole (55).