| 摘要 |
<p>This apparatus is provided with a casing (21), a valve disc (23) adapted to open and close an exhaust port (22), and a driving means (24) for opening and closing the valve disc. The valve disc (23) is provided with minute recesses and projections (23b). The driving means is provided with a cylindrical yoke (25), an iron core (26) having a cylindrical portion (26a) provided on the inner side of the yoke, and a flange portion (26b) in contact with one end portion of the yoke, a magnet (27) disposed on the inner side of the yoke and adapted to form radial magnetic flux, a movable body (28) passed through the cylindrical portion of the iron core and having the valve disc fixed to one end portion thereof, a coil (29) provided in the space between the magnet and yoke and fixed to one end portion of the movable body, and a retainer member (30) supporting both end portions of the movable body and retaining the movable body and coil out of contact with the iron core and yoke.</p> |
