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:
Jul. 26, 1994
Filed:
Jul. 08, 1993
Matthew Kujawa, Danville, IN (US);
Kevin D Thompson, Indianapolis, IN (US);
Carrier Corporation, Syracuse, NY (US);
Abstract
In a fixed-firing rate induced draft furnace, having a heat exchanger and an integrated control inducer motor, an improved method of controlling excess air comprising the steps of: providing at least one pressure switch that is responsive to a preselected pressure drop level in the heat exchanger, the pressure drop level being selected so as to be commensurate with a theoretically desired excess air level under firing operating conditions; accelerating the integrated control inducer motor until the pressure switch closes and thereupon recording a first motor speed and a first current level; calculating a first torque value based on the first motor speed and the first current level; and regulating torque applied to the integrated control inducer motor in accordance with the first torque value.