| 摘要 |
PURPOSE:To contrive to reduce the electric power consumption of a relay by a method wherein a latching type relay is provided for controlling the energizing of a electromagnetic coil. CONSTITUTION:A semiconductor switching element 27 connected in series to an electromagnetic coil 12' of a solenoid valve is provided on a forced adsorption circuit 26. A power source switch 25 is changed-over to a normal opening contact 25' by interlocking with the igniting operation of a burner, then a temperature sensor 5 is forcedly shorted for the designated time. By energizing an opening side coil 11'' of the first latching relay, the first relay contact piece 11' is opened, but an electromagnetic coil 12 is energized by a forced adsorption circuit 26. After the designated time passing, the contact piece 11' is closed by energizing an opening side coil 19''' of the first latching relay 19. In case of the short of the temperature sensor 5, the coil 11'' is energized, the solenoid valve is closed by opening the contact piece 11', then the gas supply for a burner 1 is shut-off, the burning is stopped. In case of the electric voltage dropping in a battery and the falling off of the battery, the electric charge of a capacitor 7 is flowed to the opening side 11'' of the relay 11 for opening the contact piece 11', then the burner 1 is stopped by closing the solenoid valve 12. |
