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. 29, 1994
Filed:
Jul. 30, 1991
Motoyuki Sukigara, Tokyo, JP;
Yoshiaki Sakai, Higashikurume, JP;
Teac Corporation, Tokyo, JP;
Abstract
A method of, and an apparatus for, positioning a playback head in a transverse reference position on one edge of a multitrack magnetic tape having no track identification data or other positioning patterns prerecorded thereon. A tape drive unit is provided which has an erase head with an erase gap spanning the complete width of the tape. An alternating current generator circuit is connected to the erase head for supplying thereto a constant frequency alternating current to be written as a transverse head positioning pattern by the erase head on selected part of the tape throughout its width. The positioning pattern is then read by the playback head traveling across the width of the tape from an arbitrary position on the tape, in which the playback head is fully opposed to the positioning pattern, toward one edge of the tape while the tape is being driven longitudinally. The alternating current output from the playback head is of full amplitude when the playback head is fully opposed to the positioning pattern, and gradually decreases in amplitude when the playback head starts overrunning the tape edge. The travel of the playback head across the width of the tape is discontinued when the peak value of the playback head output decreases to a predetermined percentage of that when the playback head is fully opposed to the positioning pattern.