ABNORMALITY DETECTION DEVICE FOR SOLENOID VALVE AND ABNORMALITY DETECTION METHOD FOR SOLENOID VALVE

摘要

PROBLEM TO BE SOLVED: To detect abnormality of a solenoid valve more accurately with a simple constitution.;SOLUTION: An abnormality detection device for a solenoid, in which a search coil 80 is arranged such that a magnetic flux passing through a magnetic circuit is interlinked with an energized coil 32, determines whether abnormality occurs in an electromagnetic valve 20 or not (to determine whether, for example, a spool 44 or a plunger 36 is stuck or not) based on a change amount ΔI of carry current I to the coil 32 and a magnetic flux density change ΔB based on an output voltage V1 from the search coil 80. The search coil 80 is arranged in the vicinity of a portion in which the magnetic flux density change appears to be the greatest in the magnetic circuit. Thereby, the abnormality of the electromagnetic valve 20 can be determined more accurately with a more simple constitution.;COPYRIGHT: (C)2009,JPO&INPIT