| 摘要 |
PURPOSE:To stabilize the feed rate of fuel gas over the wide range of burning of the burner by incorporating an electrically powered proportioning valve which controls the flow rate of the fuel gas and an electrically powered flow rate control valve for fine adjustment downstream of said proportioning valve which finely adjusts the fuel gas flow rate continuously. CONSTITUTION:A controller 16 outputs the opening control signal respectively to a proportioning valve 13 and an electronically controlled mechanical nozzle valve 14 to control their opening and open a shut off valve 12. The fuel gas then enters from the gas source through the open shut off valve 12 to the proportioning valve 13 where its flow rate is approximately adjusted. The fuel gas then enters into the electronically controlled mechanical nozzle valve 14 to be finely adjusted in its flow rate and then is supplied to the burner 2. By this constitution, the supply rate of the fuel gas to the burner 2 is doubly controlled by the proportioning valve 13 and the electronically controlled mechanical nozzle valve 14, so its control range can be expanded. Further, since the feed rate of the fuel gas is finely adjusted by the electronically controlled mechanical nozzle valve 13 continuously, the gas fuel feed rate to the burner 2 can be smoothly controlled. |
