Patent ID: 7280021
Filing Date: 2007-10-09
Classification: H01F

Abstract:
1. A linear solenoid comprising: a coil working to produce a magnetic attraction when energized; a plunger made of a magnetic material having a length, said plunger being disposed to be slidable linearly in a lengthwise direction of said plunger; a stator disposed to have an end facing an end of said plunger, said stator working to transmit the magnetic attraction, as produced by said coil, to the end thereof to pull said plunger to said stator, the end of said stator having a peripheral surface and a recess formed inward of the peripheral surface into which the end of said plunger enters without any contact with said stator; a first inward magnetic attraction surface formed on a peripheral edge of the recess of said stator, said first inward magnetic attraction surface being inclined to an axis of said stator so as to face an axis of said plunger; and a first outward magnetic attraction surface formed on an outer peripheral edge of the end of said plunger, said first outward magnetic attraction surface being inclined to an axis of said plunger to be opposed to said first inward magnetic attraction surface through a first magnetic gap within which the magnetic attraction appears which works to pull said first outward magnetic attraction surface to said first inward magnetic attraction surface, said first outward magnetic attraction surface being located closer to a bottom of the recess of said stator than said first inward magnetic attraction surface when said plunger is in a given stroke position.