| 摘要 |
1,220,541. Automatic pressure control. KOCKUMS MEKANISKA VERKSTADS AB. Feb.11, 1969 [Feb.12, 1968J, No.9249/69. Heading G3R. Oil fuel and combustion air supplies to the burners of a boiler and the number of burners ignited are automatically controlled by signals from oil and air pressure transducers and proportional and integral signals developed from a frequency compensated boiler pressure transducer. In Fig. 1, electrical signals corresponding to deviations of a ship's boiler pressure from a desired value are developed at 12, compensated for variations of supply frequency by a unit 13, and amplified at 11 to vary at 6 the datum of systems which control servooperated oil fuel burner valves 2 in response to oil pressure detected at 8. An integral developed at 10 is added at 9 and determines at 15 the number of burners in operation. The signals from oil pressure detector 8 also vary the datum of systems which control servo-operated combustion air dampers 1 in response to air pressure detected at 7 so that a desired air/fuel ratio is maintained. Suitable circuits involving differential and operational amplifiers, RC circuits, transistors, Zener and other diodes and smooth manual to automatic changeover are described. |
