| 摘要 |
PURPOSE: To provide a solenoid valve device for an internal combustion engine where the number of switching elements is reduced. CONSTITUTION: The drive circuit 92a of a 3-switching element series type drive circuit is formed such that, based on the upper coils 122a, 122b, 122g, and 122h and the lower coils 124a, 124b, 124g, and 124h of four valves consisting of two valves to perform the same operation and other two valves having opening periods not overlapped with those of the two valves, a current flows to only a necessary electromagnetic coil at a proper timing and a current is rapidly decreased and quenched through switching operation of fifteen switching elements 200-228 commonly used between eight electromagnetic coils. In a conventional 3-switching element series type, 18 switching elements are needed. As noted above, even when the number of the switching elements is reduced, an amount of a current flowing to the electromagnetic coil is controllable and the problem described above is dissolved.
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