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:
Aug. 13, 1991
Filed:
Mar. 15, 1990
Applicant:
Inventors:
Assignee:
Citizen Watch Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B41J / ;
U.S. Cl.
CPC ...
400124 ; 101 9334 ;
Abstract
A dot matrix print head has a print wire unit having a plurality of print wires, an armature unit having a plurality of armatures, each corresponding to the print wire, and an electromagnet unit having electromagnets. Each wire comprises a wire body and a head. A return coil spring is provided between the head of the print wire and a guide plate. The return coil spring has a small diameter end portion engaged with the head and a large diameter portion engaged with the guide plate and has a substantially conical peripheral shape. The large diameter portion engages a recess, thereby preventing rotation of the spring.