| 摘要 |
PROBLEM TO BE SOLVED: To improve response to a required flow and to prevent an increase in flow as much as possible by providing an armature whose outer periphery is slidably screwed in a rotor and whose inner periphery is slidably screwed on the shaft of a throttle valve. SOLUTION: The flow of air is controlled by a valve element 8 moved back and forth in the axial direction by the electromagnetic force of a coil controlled by a control unit. That is, in a state in which the armature 5 is not in contact with the stopper 4 of a shaft 3, an armature 5 is rotated integrally with a rotor 2 and the shaft 3 is moved slightly to the rotational angle of the rotor 2 because of the small pitch of threads cut on the inner periphery of the armature 5 in which the shaft 3 is slidably screwed. On the other hand, in a state in which the armature 5 is in contact with the stopper 4 of a shaft 3 and is rotated with the shaft 3, the shaft 3 is moved greatly to the rotational angle of the rotor 2 because of the large pitch of threads cut on the outer surface of the periphery of the armature 5 on which the rotor 2 is slidably screwed. Therefore, the amount of movement of the shaft 3 is determined by the pitch of threads cut on the inner surface of the hole of the armature 5. |
