摘要 |
PURPOSE:To unnecessitate leak in a gas thermostat for the temperature adjusting valve of a gas combustion device and facilitate control over temperature by a method wherein a main valve is provided with a sub-valve and a sub-valve closing reverse plate and the sub-valve is closed when the main valve is closed. CONSTITUTION:Under a condition in which a main valve 36 and a sub-valve 50 are opened, gas passes from an inlet 14 through a space between the main valve 36 and a valve seat 20 and the flowed out through a hole 34 and an outlet port 16. When hot temperature is sensed by a sensing pipe 66, vapor pressure of inner liquid increases to cause a bellows 62 to be extended and then the main valve 36 is lifted up through a spring receptacle 40, a center plate 38, a reversing plate 58 and a projection 60 so as to decrease a flow rate of gas. Then, the main valve 36 abuts against the valve seat 20 to close a flow of gas stream, with the result that only the flowing-out of the sub-valve 50 occurs. Further, as the temperature increases more, the reversing plate 58 reverses downwardly to close the sub-valve 50 and then a complete shutting of the gas flow. With this arrangement, no leak is necessary and so temperature control can easily be carried out. |