| 摘要 |
A device for controlling the amount of bypassed intake air, the device being configured in such a manner that a bypass (4) which bypasses a throttle valve (3) and is connected to an air intake path (2) and a cylinder-like valve hole (5) which connects to the bypass (4) are provided in a throttle body (1), a piston-like bypass valve (10) which opens and closes the bypass (4) by moving in the axial direction is slidably and non-rotatably fitted in the valve hole (5), and the bypass valve (10) and the output shaft (18) of an actuator (17) which is mounted to the throttle body (1) are connected to each other through a screw mechanism (19). The configuration above allows the bypass valve (10) to be opened and closed in the axial direction by rotation of the output shaft (18). Also, a dust trapping groove (34) is formed in the outer peripheral surface of the bypass valve (10) so as to extend in the circumferential direction of the outer peripheral surface. This prevents fine dust flowing together with intake air into a valve chamber from passing through the sliding gap between the bypass valve (10) and the valve hole, ensuring smooth operation of the screw mechanism. |
