Patent Yard Sign in
Expired Canadian patentCanada

Control method and apparatus

CA 1278563 C · Owner: Warren, John A. · Inventors: Warren, John A.; Frost, Peter L.J.; Keeble, Peter 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

The propulsive force on an optical transmission line member moving through a tubular passageway can be varied so the line travels at or close to optimum speed without risk of damage to the line or associated apparatus. A curve is provided in a portion of the passageway such that a transmission line subject to unacceptable compressive forces buckles towards the outer side of the curve. A sensor detects the presence or absence of the line at this point and a control circuit varies the propulsive force. Excessive tension in the fibre may also be detected. A modified system uses deflectors to ensure that buckling occurs by bowing in the direction towards the sensor with the transmission line …

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 January 2, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 2, 2008.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJuly 15, 1987
GrantedJanuary 2, 1991
Term endedJanuary 2, 2008
Patent numberCA 1278563 C
Classification (IPC)G02B6/44

Timeline

Timeline From CIPO dates

1988199119941997200020032006Application filedJuly 15, 1987Patent grantedJan 2, 1991Term endedJan 2, 2008

Sources & verification

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