| 摘要 |
[PROBLEMS] To optimize the valve seat shape of a valve housing to reduce the flow resistance of cooling water in a thermostat device with built-in house. [MEANS FOR SOLVING PROBLEMS] The valve seat shape of the valve housing on the downstream side of a valve seat (22), on which a bevel-shaped valve element (12) is seated, in the flow direction of the cooling water on an inner wall surface forming a cooling water passage (21) in the valve housing (20) is formed so that, in a valve opened state, a cooling water inlet part (31) can be formed so that a passage cross sectional area formed between the inlet seal part (32) of the valve seat and the top part (41) of the valve element is gradually decreased relative to the maximum passage cross sectional area on the upstream side and that the cooling water outlet part (33) can be formed so that a passage cross sectional area in a plane perpendicular to the top part is gradually increased to flow the cooling water along the top part of he valve element. |
