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:
Jul. 31, 1990
Filed:
Mar. 27, 1989
Yoji Arita, Yokohama, JP;
Mitsubuishi Kasei, Tokyo, JP;
Abstract
An actuator is disclosed, in which an movable armature and a permanent magnet mounted on a stationary yoke are disposed to face each other with a small gap. The armature has at least one pair of protruding poles which are movable along a predetermined path. The permanent magnet comprises plural pairs of juxtaposed magnetic pieces whose polarities are opposite to each other. The plural pairs of magnetic pieces are arranged in juxtaposition with each other at positions adjacent to the path of the corresponding protruding pole so that adjacent two magnetic pieces of adjacent two pairs have the same polarity with each other. The permanent magnet generates such a magnetic pattern that the amount thereof gradually decreases from both ends of the path of each protruding pole towards the boundary of the magnet pieces of the corresponding pair to avoid the influences due to the reluctance torque and the drive torque.