Patent ID: 6652252
Filing Date: 2003-11-25
Classification: F04B,H01F,H02K

Abstract:
An electromagnetic device, comprising:a core of magnetically permeable material having a longitudinal axis, a central section coaxial with said longitudinal axis, an outer section spaced outwardly from said central section, and a bridging side section bridging the outer and central sections at one side of the core, the opposite side of the core being open; a coil in the space between said central and outer sections of said core and spaced inwardly of the open side of the core such that the coil is completely recessed within the core, and the outer and central sections of the core define an extension extending laterally past the recessed coil; a movable armature of magnetically permeable material facing and aligned with said extension in the core, said armature being movable towards and away from said coil and being formed with a central recess; and a pair of springs on the opposite ends of said core and coaxial with the longitudinal axis of the core, said pair of spring mounting said armature for straight-line reciprocatory movements parallel to said longitudinal axis of the core; said armature and its recess being configured and located such that during the movement of the armature towards and away from the coil: (a) the recess receives said central section of the core; (b) the outer surface of the armature defines a first working gap with the inner surface of the core outer section at said extension; (c) and the inner surface of the armature at said recess defines a second working gap with the outer surface of the core central section at said extension.