| 摘要 |
PURPOSE:To restrain load from a valve rod to a driving portion to the minimum by coupling the end portion of a needle valve to the axial middle portion of a rotor. CONSTITUTION:When an electric current is applied to a stator 8, a rotor 9 is rotated and a slider 17 is moved up and down along a spiral guide ring 16 according to the rotation of the rotor 9. The rotation of the rotor 9 and the movement of a needle valve 3 are stopped at positions where the slider collides with the upper and lower ends of the ring. When the needle valve 3 blocks up a valve seat 2a, a coiled spring 14 is a little pressed. As a point of action of the driving force and a point of action load from the needle valve are located in the axial middle portion of the rotor which is near the center of gravity, vibration caused by rotation of a motor itself and vibration caused by a fluid of a valve portion may be minimized. |
