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. 10, 1998
Filed:
Mar. 10, 1997
Applicant:
Inventor:
Steven D Jacob, Crystal Lake, IL (US);
Assignee:
Landis & Staefa, Inc., Buffalo Grove, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B08B / ;
U.S. Cl.
CPC ...
454 61 ; 25112912 ; 251228 ;
Abstract
A fume hood exhaust terminal for controlling gas flow in an exhaust duct has an electrically driven linear actuator for angularly positioning a damper in the terminal. Drive circuitry employed in the preferred embodiment prevents the possibility of shorting out the actuator motor in the event of an input signal condition which would attempt to operate the motor in two directions simultaneously. The circuit also includes a power failure detection circuit which includes the capability of storing sufficient power to place the damper in a preferred position until power is restored to the exhaust terminal.