| 摘要 |
PROBLEM TO BE SOLVED: To provide a solenoid valve drive device for simplifying a device constitution, by using a charge pump type boosting circuit, and for exerting a good drive characteristic of the solenoid valve. SOLUTION: The solenoid valve drive device 23 comprises the charge pump type boosting circuit 3 makes a capacitor C1 generate voltage higher than battery voltage VB; a transistor T3 for communicating/shutting off a current supply path 17 for a magnetic coil L of an injector to/from an output end of the capacitor C1; and a transistor T4 for make a constant current pass through the coil L. In start of energization through the coil L, the transistor T3 is turned on to make a peak current flow from the capacitor C1 to the coil L, and then the constant current passes from the transistor T4. A diode D1 is connected between a path from the output end of the capacitor C1 to the transistor T3 and the battery voltage VB to prevent a drop in coil current I, in which a direction from the battery voltage VB side to the path side is a forward direction. COPYRIGHT: (C)2004,JPO
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