The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 21, 1987
Filed:
Oct. 15, 1985
James E Burton, Vandalia, OH (US);
Ledex, Inc., Vandalia, OH (US);
Abstract
A rotary latching solenoid of the type in which a permanent magnet causes a flux flow path to be formed between opposing pole faces of an armature and a base in order to hold the armature in an energized or latched position is improved by providing the pole faces of the armature and base with raised sector portions, each sector portion having a sector face. In the energized or latched position, the sector faces of the armature and base are adjacent to each other and lines of flux flow between them are in a circumferential direction. The holding power of such an armature and base construction is greater than that of previous solenoids in which the opposing pole faces lie in a plane perpendicular to the solenoid axis. The solenoid is further improved by providing a ferromagnetic end cap between the permanent magnet and coil, and positioning the permanent magnet at an end opposite the rotary connection between the armature and the remainder of the solenoid, which in the preferred embodiment comprises complementary ball races. The end cap provides a flux flow path for both the energizing coil and permanent magnet, and the positioning of the permanent magnet reduces the magnetization of the ball race structure to maintain it free from contamination by magnetic particles. Embodiments are shown in which the cooperating sector faces are radial and axial, and in which the faces are offset from a radius and in which the faces are inclined to the axis.