| 摘要 |
PURPOSE:To obtain the optimum control of the temperature of glow plugs at a low loss by providing a switching type DC conversion circuit with low electric loss between glow plugs equipped on an engine and a car storage battery for giving a dropped voltage of the storage battery to glow plugs. CONSTITUTION:A DC-DC conversion circuit (DC-DC converter) 6 is connected to a car storage battery 1, and supplies electric power to glow plugs 5a-5d via a switch 7. For preheating before starting, only a switch 2 is closed, and current is directly supplied to glow plugs 5a-5d from the storage battery 1. After the starting of an engine, the switch 2 is opened, and the switch 7 is closed. The DC-DC converter 6 supplies a fixed DC voltage determined at a Zener diode 6h to glow plugs 5a-5d via the switch 7. This construction permits to obtain a stable after-glow at the optimum value. |
