Patent · US Expired

Method of and apparatus for indicating length and remaining recording capacity of a recording tape

US4280159A · kind A · utility

40Cited by
7References
22Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 30, 1979
Grant dateJul 21, 1981
Priority date
Expiry dateApr 30, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B27/13
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for indicating the type, such as in terms of overall recording capacity, and remaining recording capacity of a recording tape. The tape is transported at a predetermined speed from a supply reel to a take-up reel. The rotations of the respective reels are sensed and the rotational periods T.sub.s and T.sub.t of the supply and take-up reels, respectively, are determined. Based upon these determined rotational periods, predetermined characteristics, such as the overall recording capacity, of the recording tape are indicated, irrespective of the arbitrary amount of tape which, initially, is wound upon the take-up reel. For example, a set of characteristics is stored for each value of T.sub.s.sup.2 +T.sub.t.sup.2 ; and the one set which is associated with the determined value T.sub.s.sup.2 +T.sub.t.sup.2 is selected. Also, the determined rotational periods T.sub.s and T.sub.t are combined with certain of said characteristics to indicate the amount of tape which remains upon the supply reel when that amount initially is unknown. The latter operation is carried out in accordance with the expression T.sub.R =P/1+.alpha..sup. 2 -Q, wherein T.sub.R represents the reco…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.