Method of detecting hot spots in a rotary heat exchanger
US4813003A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1986 |
| Grant date | Mar 14, 1989 |
| Priority date | — |
| Expiry date | Jun 23, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF28F27/006
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A detector (32) monitors infrared ray emissions from an air preheater (10) rotor (14) to detect a temperature rise that precedes a fire within air preheater (10) with each sensor output being processed independently by signal processing electronics. The instantaneous minus the average temperature of rotor (14) is calculated and compared to a variable trip level signal to determine whether a hot spot has been detected. The detector (32) scans across the face of rotor (14) until an initial hot spot is detected, whereupon the scanner motor (58) ceases operation thereby locating the scanner over the rotor radial position of the detected hot spot. If the same hot spot is detected on the next subsequent rotor pass, a hot spot alarm (60) is energized. If the hot spot is not detected on the next subsequent rotor pass, detector scanning is resumed by energizing scan motor (58).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.