| 摘要 |
PURPOSE:To simplify the structure of a passage switch device by using a coiled spring formed by a shape memory alloy as a sensor portion, a control portion and a driving portion. CONSTITUTION:When the temperature of a fluid flowing into the interior of a main body 1 is lower than a set temperature, a coiled spring 6 is elongated, so that a piston 5 is moved toward a port 3 and brought into contact with the port. At this time, the port 3 is closed. On the other hand, a port 4 is opened because the piston 5 is brought into contact with the port 3. On the contrary, when the temperature of a fluid is higher than a set temperature, the coiled spring 6 is contracted, and simultaneously the piston 5 is separated from the port 3 and positioned in such a manner that the port 4 is closed by the peripheral wall of the piston 5. At this time, the port 4 is closed, and the port 3 is opened. |
