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:
Jan. 01, 1985
Filed:
Apr. 22, 1983
Takaharu Idogaki, Okazaki, JP;
Hisasi Kawai, Toyohashi, JP;
Kyo Hattori, Susono, JP;
Kazuhiro Sakurai, Gotenba, JP;
Nippon Soken, Inc., Nishio, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
A rotary actuator for driving a fluid control valve comprises a yoke which forms a closed magnetic path an excitation coil which produces a magnetic flux in the yoke, a permanent magnet which is rotatably arranged in a through hole or in a slit formed in the yoke, and a restoring spring which produces a force acting against a rotational torque generated in the magnet by a main magnetic flux which flows through the yoke and the permanent magnet when the excitation coils is energized. Shielding portions are formed on both sides of the ends of the yoke, which ends oppose the permanent magnet, so as to substantially shield the permanent magnet together with the ends of the yoke, whereby a magnetic reluctance of a path of the magnetic flux remains substantially constant irrespective of the rotating position of the permanent magnet with respect to the yoke when the excitation coil is de-energized.