Patent Yard Sign in
Expired Canadian patentCanada

Contact recording disk file with a magnetoresistive read sensor

CA 2102087 C · Owner: Hitachi Global Storage Technologies Netherlands B.V. · Inventors: Sawatzky, Erich; Dovek, Moris Musa; Lam, Donald K. F.

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 contact magnetic recording rigid disk file utilizes a magnetoresistive (MR) sensor for reading data recorded on the disk. The disk file may be of the liquid-bearing type of contact recording with the MR sensor supported on the trailing end of a carrier which rides on the liquid bearing. The performance of the disk file is enhanced by including means for minimizing the effect of a discovered baseline read signal modulation. The modulation has been determined to be caused by variable cooling of the temperature-sensitive and temperature-elevated MR sensor by the disk with the temperature variation being directly related to the variation in head-disk spacing caused by the waviness of the …

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

  • Filed October 29, 1993 and granted November 24, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 29, 2013.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 29, 2015.
  • 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 29, 1993
GrantedNovember 24, 1998
Term endedOctober 29, 2013
Patent numberCA 2102087 C
Classification (IPC)G11B5/01 +2 more

Timeline

Timeline From CIPO dates

1994199619982000200220042006200820102012Application filedOct 29, 1993Patent grantedNov 24, 1998Term endedOct 29, 2013

Sources & verification

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