Patent Yard Sign in
Expired Canadian patentCanada

Thermal circuit breaker

CA 1290795 C · Owner: Merchant, Donald K. · Inventors: Merchant, Donald K.

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

An improved thermal circuit breaker is disclosed, featuring a U-shaped bimetallic element which latched an escapement locking arm which holds a spring biased moving contact against a fixed contact when the breaker is in the contacts closed position. The improved thermal element has terminal portions which are of lesser electrical resistivity than are other portions of the element. The relative orientation of the metals of the bimetallic element in the terminal portions are reversed with respect to their orientation in the remainder of the bimetallic element. In this way ambient temperature compensation is provided to the breaker such that the current rating of a given breaker does not vary …

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 15, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 15, 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.
FiledFebruary 24, 1988
GrantedOctober 15, 1991
Term endedOctober 15, 2008
Patent numberCA 1290795 C
Classification (IPC)H01H73/30 +1 more

Timeline

Timeline From CIPO dates

1989199119931995199719992001200320052007Application filedFeb 24, 1988Patent grantedOct 15, 1991Term endedOct 15, 2008

Sources & verification

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