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. 11, 1989
Filed:
Nov. 17, 1987
Tatsuya Koyama, Tokyo, JP;
Tetsuhiro Yamada, Tokyo, JP;
Hirokazu Andou, Tokyo, JP;
Katsuya Kamimura, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
A wire-type print head comprises an armature to which a rear end of a printing wire is fixed, a core having its forward end adjacent to a rear surface of the armature, a leaf spring having a first end fixed near a permanent magnet and a second end fixed to the armature, and an auxiliary core positioned between the permanent magnet and the core, and having a forward end adjacent to the rear surface of the armature. An electric current is made to flow through a coil wound on the core for generating a magnetic flux through the core in a direction to cancel the magnetic flux due to the permanent magnet. When the coil is not energized the armature is attracted toward the core to resiliently deform the leaf spring. When the coil is energized the armature is released and moved forward by the action of the leaf spring. The rear surface of the armature is kept in contact with the front end of the auxiliary core so that the front end of the auxiliary core forms a fulcrum point for swinging of the armature.