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:
Nov. 12, 1985
Filed:
Nov. 21, 1983
James E Wooldridge, Louisville, KY (US);
Allis-Chalmers Corporation, Milwaukee, WI (US);
Abstract
An air volume control ventilation system which minimizes variation in air volume flowing through the system has a fan for drawing air through fixed-resistance filter means including a roll filter, an electrostatic filter, and a high efficiency filter; a variable-resistance volume control damper operated, when an actuator therefor is energized in opposite directions, to open and to close and thus vary the volume of air flowing through the system; and a differential static pressure switch connected across the fan and being provided with a normally open high limit set of contacts adapted to close and complete a circuit to open the damper when the differential pressure across the switch rises to a first predetermined limit and also a low limit set of normally open contacts adapted to close and complete a circuit to shut the damper when the differential pressure falls below a second predetermined limit, whereby the damper is alternately open and shut and the differential pressure across the fan is maintained within a narrow band between the first and second limits.