| 摘要 |
PURPOSE:To restrain a shortage of air for combustion due to the fluctuation of load and to improve the combustion performance of a burner by applying a voltage at a correction value determined on the basis of a difference between the preset number of revolutions of a blower, which is decided in advance in accordance with each of combustion quantities, and an output from a detection section for the number of revolutions to the drive voltage of the blower and by releasing the correction when the output from the detection section for the number of revolutions is reduced and the output from a current detection section increases after the correction. CONSTITUTION:A control section 7 for driving a blower 1 sets the drive voltage of the blower 1 and the number of revolutions thereof as a preset value in advance corresponding to a combustion quantity which is obtained by the control voltage of a proportional control valve 5. The drive voltage at the ordinary time is denoted as V1. If a load point is varied by the influence of outside disturbance, the number of revolutions increases and an electric current is reduced. Such a difference is outputted by a comparison section 10, and if a judgement section 11 determines that the current has been reduced, this is judged as the fluctuation of load, whereby a correction section 12 decides a voltage correction value DELTAV1 on the basis of the difference between the combustion quantity and the number of revolutions, and the control section 7 applies a drive voltage V1+DELTAV1 to the blower 1. As a result, the quantity of air is restored to the air quantity at the preset value. Then, when the outside disturbance is eliminated, the number of revolutions is reduced and the current increases. Therefore, the correction section 12 releases the control, and the control section 7 returns a drive voltage to that at the ordinary time. |
