| 摘要 |
PURPOSE:To perform control depending on the temperature without any independent temperature detection elements by disposing a magnetic temperature- sensitive member, having temperature dependent magnetic characteristics, at a part of a magnetic circuit CONSTITUTION:When a thermoferrite is employed as a magnetic temperature- sensitive member 14, lines of magnetic flux A normally flows from N pole of a magnet forming a rotor 13 through pole pieces 11-1, 11-2 to a yoke 10 (as shown by solid lines) thence returns through pole pieces 11-3, 11-4 back to S pole. When the temperature rises, the permeability of the pole pieces 11-1, 11-4 (magnetic temperature-sensitive member 14) decreases to weaken the lines of magnetic flux passing through the pole pieces 11-1, 11-4 and to strengthen the lines of magnetic flux on the side of pole pieces 11-2, 11-3 (dot line). Consequently, the magnet (rotor) 13 rotates counter-clockwise about a shaft 12. When the shaft 12 rotates in the direction for closing the valve, the valve can be closed as the temperature rises. This structure realizes control depending on the temperature without any independent temperature detection element. |
