LINEAR SOLENOID DEVICE

摘要

A linear solenoid device comprises a cylindrical armature or plunger freely movable within the central opening of a stator which comprises a cylindrical coil wound between a pair of annular end pole members and surrounding one or more intermediate annular pole members. The intermediate pole members are axially spaced and aligned with the end pole members by a bobbin which preferably is injection molded. The armature has plural axially spaced and aligned annular pole members concentrically arranged within the central opening of the single cylindrical coil. The magnetic stator and armature poles take the form of rings which are dimensioned and arranged so that the magnetic flux generated by the coil passes in a series path alternately from the stator to the armature rings and then through a cylindrical magnetic casing which forms a magnetic flux path between the end pole members. The armature includes a support body of non-magnetizable material which may be plastic and can be injection molded. The support body has annular bearing surfaces formed between the armature rings for maintaining annular air gaps between stator pole member and armature rings and for positioning the armature within the central opening.