Patent ID: 6633157
Filing Date: 2003-10-14
Classification: F01L,G01B,G01D,Y10T

Abstract:
Displacement detecting device for detecting displacement of a movable intake/exhaust valve; comprising:a spring seat for supporting a spring, a transfer shaft for connecting the spring seat and the intake/exhaust valve, a magnet provided on the spring seat and the magnet magnetized in the direction of movement of the intake/exhaust valve, a magnetic sensor having at least a first surface and a second surface provided between the magnet and the spring, the magnetic sensor detecting magnetic flux generated by the magnet and outputting a sensor output indicative of displacement of the intake/exhaust valve, wherein at least a portion of the first surface of the magnetic sensor lies tangentially to a portion of the magnet, and a piece of a magnetic material provided adjacent to and behind the magnetic sensor, said piece facing the second surface of the magnetic sensor for attracting magnetic flux from the magnet toward the magnetic sensor.