Patent EP0322119A2 successfully refreshed from Google Patents.
EP0322119A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Information reproducing apparatus for recording tape
Assignee: Panasonic Holdings Corp
•
Filing: 1988-11-25
•
Granted: —
•
Expires: 2008-11-25
Abstract
Abstract An information reproduding apparatus serves to retrieve at high speed position information of a tape-shaped recording medium on which tracks are formed to record information and the position information. This appartus comprises a tape speed detecting unit for continuously detecting the running speed of the tape-shaped recording medium, a cylinder speed setting unit for setting target values of rotation of a rotary cylinder for making constant the component of speed at which the head moves in a track direction according to the output of the tape speed detecting unit, and a cylinder control circuit for controlling the rotary cylinder so as to adapt its rotation to the target value of velocity of the cylinder set by the cylinder speed setting unit. By rotating the cylinder by the number of rotations at which a data reproduction can take place at a tape speed obtained by the tape speed detecting unit, the positional information can be positively read out even in a transient state during when the running speed of the recording medium chagnes.
Inventors
- 👤 Kazuo Arai
- 👤 Kiyoshi Ota
- 👤 Kouji Wakiyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 20:09
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/02; G11B15/18; G11B15/1808; G11B15/1875; G11B15/46; G11B15/467; G11B15/4673; G11B27/00; G11B27/005; G11B27/10; G11B27/11; G11B27/13; G11B27/17; G11B27/19; G11B27/28; G11B27/30; G11B27/3027; G11B2220/00; G11B2220/90; G11B2220/91; G11B2220/913
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
186 words
An information reproducing apparatus for reproducing information from a tape-shaped recording medium on which positional information of the recording medium is recorded in each of slant information tracks, which apparatus comprises: heads for reading out recorded information; a rotary cylinder on which said heads are mounted; reproducing means for reproducing the informations recorded on said recording medium via said heads; two reels around which said recoding medium is wound; tape rapid-drive means for running said recording medium at a high speed as compared with that at the time of recording by use of said two reels; tape speed detecting means for continuously detecting the running speed of said recording medium; cylinder speed setting means for setting a target value of speed of said rotary cylinder for making constant the component of the speed of the heads at which the heads moves in the track direction according to an output of said tape speed detecting means; and cylinder control means for controlling said rotary cylinder so as to adapt its rotation to the target value of speed of the cylinder set by said cylinder speed setting means.
Claim 2
Dependent Claim
186 words
An information reproducing apparatus for reproducing information from a tape-shaped recording medium on which positional information of the recording medium is recorded in each of slant information tracks, which apparatus comprises: heads for reading out recorded information; a rotary cylinder on which said heads are mounted; reproducing means for reproducing the informations recorded on said recording medium via said heads; two reels around which said recoding medium is wound; tape rapid-drive means for running said recording medium at a high speed as compared with that at the time of recording by use of said two reels; tape speed detecting means for continuously detecting the running speed of said recording medium; cylinder speed setting means for setting a target value of speed of said rotary cylinder for making constant the component of the speed of the heads at which the heads moves in the track direction according to an output of said tape speed detecting means; and cylinder control means for controlling said rotary cylinder so as to adapt its rotation to the target value of speed of the cylinder set by said cylinder speed setting means.
Claim 3
Dependent Claim
52 words
An apparatus as defined in claim 1, wherein the tape speed detecting means comprises an idler adapted to rotate in contact with said recording medium, and an encoder on a shaft to which said idler is also attached for producing an output in proportion to the number of rotaions of the idler.
Claim 4
Dependent Claim
152 words
An apparatus as defined in claim 1, wherein the tape speed detecting means comprises: tape constant speed drive means for running said recording medium at a substantially constant speed; two reel speed detectors for detecting the respective number of rotaions of said two reels; a controller for running said recording medium by use of said tape constant speed drive means for a predetermined period of time; reel diameter calculating means for calculating the roll diameter of said recording medium wound around the respective reels based on the output pulse of said reel speed detector during the time when said controller urges the said tape constant speed drive means to drive said recording medium; and tape speed calculating means for calculating the running speed of said recording medium based on the outputs of said reel speed detector and said reel diameter calculation means when said tape rapid-speed drive means drives said recording medium.
Claim 5
Dependent Claim
184 words
An apparatus as defined in claim 3, wherein the two reel speed detectors each include a pulse generator for producing pulses in proportion to the number of rotations as an output of reel speed, the reel diameter calculating means includes two counters for counting pulses generated by said two reel speed detectors for a predetermined period of time when said controller urges said tape constant speed drive means to run said recording medium, and the tape speed calculating means comprises: a reel square sum calculating circuit for calculating a sum of squares of the respective reciprocal numbers of the outputs of the counter included in said reel diameter calculating means; a pulse cycle square sum claculating circuit for calculating a sum of squares of the respective output pulse cycles of said two reel speed detectors when said tape high-speed drive means drives said recording medium; a divider for calculating a ratio of outputs of said reel square sum calculating circuit and said pulse cycle square sum calculating circuit; and a square root circuit for taking result square root of an output of said divider.
Claim 6
Dependent Claim
157 words
An apparatus as defined in claim 3, wherein two reel speed detectors each include pulse generators for generating pulses in proportion to the number of rotations as an output reel speed, the reel diameter calculating means includes two counters for counting pulses generated by said two reel speed detectors for a predetermined period of time when said controller urges said tape constant speed drive means to run said recording medium, and the tape speed calculating means comprises: a reel reciprocal number sum calculating circuit for calculating a sum of reciprocal numbers of outputs of the counters included in said reel diameter calculating means; a pulse cycle sum calculating circuit for calculating a sum of output pulse cycles of said two reel speed detectors when said tape high-speed drive means drives said recording medium; and a divider for calculating a ratio of outputs of said reel reciprocal number sum calculating circuit and the pulse cycle sum calculating circuit.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.