| 摘要 |
PROBLEM TO BE SOLVED: To reduce power consumption by assisting a thrust of a solenoid part by using the magnetic force of a permanent magnet, and to detect abnormality of a valve. SOLUTION: A magnet unit 70 is joined to a tip end of a shaft 38 of a solenoid part 30. A magnetic attraction member 78 formed as a flanged and bottomed cylinder to surround the magnet unit 70 is arranged between the solenoid part 30 and a pressure control valve part 40. A magnetic field detection unit 80 for detecting a magnetic field is attached to the magnetic attraction member 78. Thus, a solenoid force of the solenoid part 30 can be assisted by the magnetic force of the magnet unit 70, consequently electrical energization to an electromagnetic coil 32 is suppressed, resulting in reduced power consumption. By monitoring the relationship between a solenoid current and an output voltage detected by the magnetic field detection unit 80 (hall element 82), it is determined whether or not a valve (plunger) stick has occurred. COPYRIGHT: (C)2013,JPO&INPIT |
