| 摘要 |
PURPOSE:To enable a preheating condition to be correctly displayed by compact construction further with a low price, by changing the voltage across both ends of a preheating display lamp in accordance with a rapid change to the resistance value in a PTC ceramic resistor so as to vary intensity of illumination of the preheating display lamp. CONSTITUTION:If a key switch contact 3 is closed, the voltage of a battery 7 is applied to glow plugs 4 via a fixed resistor 12 and a PTC ceramic resistor 2 connected in parallel to each other. At initial time of electrification when a resistance value of the ceramic resistor 2 is very small as compared with the resistance value of the fixed resistor 12, the battery voltage is applied to the glow plugs 4 without causing any voltage drop on the half way of supply, thus rapidly heating the glow plugs 4 and increasing their temperature. Here the high battery voltage, being applied to also a preheating display lamp 6 parallelly connected to the glow plugs 4, brightly turns on the preheating display lamp 6. In this way, a preheating condition can be correctly recognized by changing intensity of illumination of the preheating display lamp 6. |
