| 摘要 |
<p>PURPOSE:To enable flow rate control to be conducted over the wide valve angle range accurately and at a high speed by forming an outside surface of a valve into a shape wherein fluid passing is prevented in a valve box at an optional angle, and forming a groove whose either depth or width is continuously varied in the rotational direction of the valve. CONSTITUTION:A spherical valve 13 to be rotated together with a rotary shaft 12 is housed in an approximately cylindrical valve box 11, so as to be rotated by a motor 16. Since the spherical valve 13 has a radius corresponding to that of a cylindrical passage 14, the spherical surface of the valve 13 is always engaged with the front surface of the passage 14 to prevent fluid from passing. A groove 13a extended over the angle slightly smaller than 180 deg. as viewing from the direction of the rotary shaft 12 is formed on the spherical front surface of like this valve 13. Thereby, when the rotational angle theta of the valve body 13 is 0 deg., the fluid is prevented from passing, when the angle theta is beyond 0 deg., the fluid is started to flow through the valve. Hereafter, flow rate corresponding to the rotational angle theta of the valve 13 is allowed to pass.</p> |
