Make up air controller for use with fume hood systems
US4773311A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 24, 1986 |
| Grant date | Sep 27, 1988 |
| Priority date | — |
| Expiry date | Nov 24, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24F2011/0005
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Method and apparatus for varying the make-up air volume of an HVAC system used in conjunction with a laboratory fume hood. The invention maintains a constant difference in air volume between the total air volume exhausted from the laboratory, including the variable fume hood exhaust volume and the make-up and supply air provided by the HVAC system. The invention provides a continuous modulation of the make-up air volume which tracks the exhaust volume to maintain a constant preset differential between the makeup and exhaust volumes. The invention includes a preferred embodiment in which a signal from a sash height transducer is used to control the volume of make-up air.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.