Patent Yard Sign in
Expired Canadian patentCanada

Method and apparatus for measuring dynamic track misregistration

CA 1309176 C · Owner: International Business Machines Corporation · Inventors: Yarmchuk, Edward J.; Chainer, Timothy J.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A method and apparatus for measuring dynamic head and track misregistration in, for example, a magnetic disk file. A reference signal waveform is recorded onto a track on a recording medium. The track has a center line and an off-center line parallel to the center line. The recorded reference signal waveform is read a plurality of times with the transducer centered approximately above the off-center line of the track to produce a plurality of off-track playback signal waveforms. A track misregistration signal waveform is produced by computing the difference between one off-track playback signal waveform and the average off-track playback signal waveforms. YO987-029

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted October 20, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 20, 2009.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledOctober 20, 1988
GrantedOctober 20, 1992
Term endedOctober 20, 2009
Patent numberCA 1309176 C
Classification (IPC)G11B21/10 +1 more

Timeline

Timeline From CIPO dates

1989199219951998200120042007Application filedOct 20, 1988Patent grantedOct 20, 1992Term endedOct 20, 2009

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.