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. 05, 1984
Filed:
Jul. 28, 1981
Hiroyuki Sugiyama, Isehara, JP;
Masaki Sakurai, Yokohama, JP;
Ryuzo Abe, Yokohama, JP;
Yasuhiro Yusa, Fujisawa, JP;
Kenji Yoshihara, Chiba, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
An apparatus for detecting position of a reproducing transducer in a rotary recording medium reproducing apparatus which reproduces an information signal recorded in a rotary recording medium by a reproducing transducer which is transferred towards the radial direction of the rotary recording medium, comprises a single photo-detector having a light-emitting element and a light-receiving element, provided in a manner so as to be transferred unitarily with the reproducing transducer, a light interrupting plate provided at a fixed part of the rotary recording medium reproducing apparatus, for operating together with the photo-detector, and a position detection signal producing circuit for producing a position detection output signal according to an output of said photo-detector, to indicate that the reproducing transducer has passed a position corresponding to the outermost peripheral position and the innermost peripheral position of the recorded region in the rotary recording medium. The light interrupting plate has a configuration so as to change state between a light interrupting state and a non-interrupting state with respect to the photo-detector, as the reproducing transducer passes a position corresponding to an outermost peripheral position and an innermost peripheral position of a recorded region in the rotary recording medium.