| 摘要 |
PROBLEM TO BE SOLVED: To provide a drain valve for cold regions that requires neither a solenoid valve nor an electrically operated valve, reduced in cost and operating time, creates no noise, shows excellent quietness, and is suited for purposes, such as prevention of freezing even if water draining operation is forgotten and utilization without water draining as much as possible even in winter. SOLUTION: One end of a valve body 8 that closes a drain valve seat 4 communicated with a drain port 3 of a valve box 1 is connected with a shape memory alloy wire 15 that shrinks when heated, and the diameter of the intermediate part of the valve body 8 is formed approximately equal to that of the drain valve seat 4 so as to seal the drain valve seat 4. In addition, by supplying power to the shape memory alloy wire 15 and heating it, the valve body 8 is detached from the drain valve seat 4 to discharge water from a water inlet 2 to the drain port 3. When power supply is stopped, the drain valve seat 4 is closed by a return spring 17 or water pressure. COPYRIGHT: (C)2004,JPO&NCIPI |
