The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 14, 1991
Filed:
Jan. 27, 1989
William R Landis, Bloomington, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A method and apparatus detect a faulty air switch in a heating system which has an operation cycle comprising a plurality of operating periods. The air switch senses air flow in the heating system and causes air flow limit contacts to open when the air flow is outside a predetermined limit. The air flow is outside the predetermined limit during a first operating period of the operation cycle. A series circuit comprises the air flow limit contacts, coupled in series with other limit contacts between a limit sense terminal and an energized input terminal. The other limit contacts should be closed during the first operating period of the operation cycle. The limit sense terminal is sampled during the first operating period to determine whether the limit sense terminal is energized. Based on whether the limit sense terminal is energized, the air switch is determined to be faulty or operating properly.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile