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:
Feb. 03, 1998
Filed:
Jun. 13, 1996
Kazuo Sasaki, Miyagi, JP;
Shuichi Kikuchi, Miyagi, JP;
Sony Corporation, Tokyo, JP;
Abstract
A tape cartridge comprises a base plate, a pair of tape reels rotatably supported by a pair of upstanding reel shafts which shafts are supported on the base plate, and a magnetic tape wound on the tape reels wherein a plurality of tape guides are provided to define a tape travel path. The base plate is formed with an aluminum-alloy plate with a hard protective film on both faces of the aluminum-alloy plate and small impressions in the hard protective film for elimination of residual strain. The hard protective film is formed by an anodic oxidation coating. In order to eliminate residual stress or strain existing in the base plate formed by a punching operation, each of the small impressions is formed by impressing the hard protective film to a depth within a thickness of the hard protective film or to a depth within a permissible limit of deformation (elongation) of the hard protective film.