Opacity monitor

US4381153A · kind A · utility

Assignee

• The Babcock & Wilcox Company · US

Inventors

• Thomas L. Bohl · London, US
• George R. Hall, II · West Hollywood, US
• Sharon L. Zimmerlin · Chagrin Falls, US

Key dates

• Filing date: Aug 28, 1980
• Grant date: Apr 26, 1983
• Expiry date: Aug 28, 2000

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N21/534
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An opacity monitor (10) including a light source (12) mounted on one side of a duct (14), and a detector (16) mounted on the opposite side of the duct is disclosed. The light source (12) and the detector (16) are rotated by motor means (26, 36), respectively, between a first position aligned with each other along an open light path defined across the duct (14) and a second position aligned with each other on opposite sides of a calibration tube (18) extending across the duct (14). Shutters (28, 38) rotate with the light source (12) and the detector (16), respectively, and are aligned with the calibration tube (18) when the light source (12) and the detector (16) are aligned with the open light path, and vice versa.