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:
Jun. 07, 1988
Filed:
Aug. 07, 1986
Koji Uozumi, Kanagawa, JP;
NHK Spring Co., Ltd., Yokohama, JP;
Abstract
In a print head comprising a plurality of magnetic circuits each of which comprises an armature supported by a spring, a permanent magnet for biasing the armature in one direction, and an electromagnet which can be energized so as to cancel the biasing force of the permanent magnet, so that a print wire fixed to the armature may be driven by energizing the electromagnet and thereby driving the armature with the restoring force of the spring. The cross-sectional areas of the paths of magnetic flux between neighboring electromagnet circuits are made uneven. This can be achieved by providing base portions which are common to two electromagnet core portions. Thereby, the print pressure of all the print wires is made uniform and an increase in printing speed and improved print quality can be achieved at the same time.