PURPOSE: To improve detection accuracy by improving detection sensitivity in a low velocity region, and to provide a recirculated gas amount controller for an EGR device for which a magnetic stroke detection sensor having excellent heat resistance and heat resistant cycle properties is used.
CONSTITUTION: An EGR valve 1 is provided on EGR routes 7, 10 communicating between the exhaust route 8 and an intake route 11 of an engine, and the flow of exhaust gas recirculated in the engine is adjusted by controlling the opening of the EGR valve 1. A valve shaft 5 for supporting the valve element 4a of the EGR valve 1 is made of non-magnetic substance, and magnetic parts are formed on the valve shaft 5 at a specific interval. A magnetic stroke detection sensor 15 for detecting the amount of movement of the valve shaft 5 is also provided. The stroke detection sensor 15 comprises first and second detection side coils 17, 18 and a common exciting side coil 16 for applying a.c. bias magnetic field to the detection side coils 17, 18.
INOUE KAZUO
TANI MICHIHIRO
UDA JITSUO
ONO MITSURU
TAKEUCHI YUKIHISA
MINERVA KK
SENSOR TECH KK
NIPPON DENSO CO