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:
Mar. 17, 1992
Filed:
May. 30, 1991
Masami Horii, Shizuoka, JP;
Tokyo Electric Co., Ltd., Tokyo, JP;
Abstract
A dot printer head including a housing that contains electromagnets toward its back end, the electromagnets having cores positioned opposite to armatures which are supported detachably against the core. The housing slidingly supports needles connected to the armatures and pushed in retracting direction thereof. An armature stopper made of an elastic substance is fixedly attahced to the inside of a cover which closes the opening at the back end of the housing, the armature stopper being in contact with the vicinities of the free ends of the armatures. A spacer is made of a substance with a linear expansion coefficient such as to ensure the same expansion as that of the armature stopper in thickness, the spacer connecting the inside of the cover to the opening edge of the housing. In this setup, when the armature stopper extends in thickness in keeping with the temperature rise inside the housing during printing, the spacer expands by exactly the same thickness to retract the cover. This allows the armatures to return always to the same position.