Patent attributes
A coil spring of a throttle valve device around a shaft between a valve and a valve gear has one end rotated together with a first guide, and another end rotated together with a second guide. The both ends of the coil spring contact a holding portion and a driving portion at a valve intermediate position of the shaft. The driving portion pushes the one end of the coil spring while the holding portion holds the other end of the coil spring during movement of the shaft from the valve intermediate position toward a valve fully-open position or a valve fully-closed position. The first guide and the second guide have insertion holes that face each other in an axial direction when the both ends of the coil spring are positioned near the valve intermediate position of the shaft and are not in contact with the holding portion.