Patent attributes
A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a valve seat. A sleeve is mounted on the valve seat. An armature core is slidably received in the sleeve. The sleeve includes a first ferromagnetic portion adjacent the valve seat, a second ferromagnetic portion, and an annular region defining an area of increased magnetic reluctance. A part of the first portion of the sleeve defines a radial magnetic pole for the generally radial flow of magnetic flux from the armature to the sleeve. A portion of the valve seat adjacent the armature defines an axial magnetic pole for the generally axial flow of magnetic flux from the armature to the valve seat. Together, the generally radial flow of flux and the generally axial flow of flux generate a force urging the armature from an open position toward a closed position when the coil is energized.
