CONTROLLING DEVICE FOR SOLENOID DRIVE VALVE

摘要

PROBLEM TO BE SOLVED: To surely operate a valve at a time of starting an engine without influence of a sensor for detecting a valve lift position and capacity of a capacitor for power supply. SOLUTION: When an engine is started, a high-level trigger signal is output to a base of a power transistor 85a or 85b to be turned on. The power transistor 85a is exclusive for starting a valve-closing solenoidal coil drive circuit 36. The power transistor 85b is exclusive for starting a valve-opening solenoidal coil drive circuit 37. A valve-opening solenoidal coil 5 or a valve-closing solenoidal coil 6 is directly connected to a battery power source 7 to be conducted so that a valve which is in semi-open state and at a center valve position is surely opened or closed, without using a primary overexcitation power source or a secondary overexcitation power source.