| 摘要 |
PROBLEM TO BE SOLVED: To provide a combustion control mechanism of a gas burner, in which an inexpensive shut-off valve with no governor can be used.SOLUTION: A combustion control mechanism of a gas boiler comprises a first pressure sensor 31 detecting a differential pressure across a resistance element 11 for measuring a flow rate in a supply passage 1, and a fuel gas amount control mechanism 10 in a supply passage 2. The control mechanism 10 comprises a flow regulation valve 23 regulating a flow passage cross-sectional area of the supply passage 2, a first shut-off valve 22 on the primary side of the flow regulation valve 23, and a second pressure sensor 32 detecting a pressure between the flow regulation valve 23 and the shut-off valve 22, a pressure on the secondary side of the flow regulation valve 23, or a differential pressure across a resistance element 24 for measuring a flow rate on the secondary side of the flow regulation valve 23. The flow regulation valve 23 has a regulation mechanism 33 that regulates opening of the valve according to the pressure values detected by the first pressure sensor 31 and the second pressure sensor 32 to control a fuel gas amount flowing in the supply passage 2 so that an air-fuel ration becomes constant.SELECTED DRAWING: Figure 1 |
