| 摘要 |
<p>PURPOSE:To contrive the reduction of heat generation in a coil of a solenoid valve and power consumption by giving predetermined starting voltage only for a fixed time to the solenoid valve, changing a compressing capacity, when it is in excitation starting thereafter low holding voltage necessary for holding the solenoid valve in its energized condition. CONSTITUTION:In the time of acceleration operation or the like, high starting voltage is applied to a coil 21 of a solenoid valve 20, and actuating the solenoid valve 20 to be energized by exciting the coil 21, a compressing capacity is decreased. When a capacitor C is charged with a predetermined charge, a transistor Tr1 is turned off, and holding voltage lower than the starting voltage is given to the coil 21 by a transistor Tr2 in its on-condition. Consequently, the solenoid valve 20 reduces its consumption power while heat generation of the coil 21.</p> |
