Structure for coupling shaft and valve in throttle body

A structure for coupling a throttle valve (12) and a throttle shaft (13) in a throttle body reliably receives thrust force applied to the throttle shaft (13), and assures smooth rotation of the throttle shaft (13) and a wide open area of a bore when the throttle valve (12) is fully opened. In this structure, the throttle valve (12) is in the shape of a disc, and the throttle shaft (13) is in the shape of a plate parallel to the throttle valve (12), and is formed with a recess (13e). The throttle valve has a through-hole (12b), and projections (12d) to be fitted in the recess (13e) of the throttle shaft (13). Further, a thrust surface (12e) is formed at an entrance of the through-hole (12b), and receives thrust force applied to the throttle shaft (13) when brought into contact with an inner surface of a bore.