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:
Apr. 26, 1988
Filed:
Aug. 28, 1986
Turgay Goker, Spring Valley, CA (US);
Henry L Alioth, Carlsbad, CA (US);
Charles J Spatafore, Poway, CA (US);
TEAC Corporation of America, Montebello, CA (US);
Abstract
This system moves magnetic tape past the read/write head at a constant velocity by separately servo controlling the source reel motor and the take-up reel motor. Separate fine encoders are associated with each reel, each encoder providing multiple pulses for each revolution of the respective reel. Two radius calculation circuits each receive pulses from a respective one of the encoders and each calculate therefrom the radius values of tape on both of the reels. A radius information selector then selects, for use in controlling the motors, that set of radius values which is calculated by the calculation circuit which is receiving encoder pulses at the greater sampling rate. Separate servo circuits drive the two motors at respective angular velocities determined by utilizing the selected set of radius values. In each drive circuit, the associated tape radius is multiplied by the actual reel angular velocity, as indicated by the time duration between consecutive pulses from the encoder associated with that reel. Each servo maintains this product equal to a preselected tape linear velocity value, thereby causing the separate motors to rotate the reels so as to establish the desired constant linear tape velocity.