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:
Jan. 04, 2000
Filed:
Apr. 21, 1999
Applicant:
Inventors:
Andrew L Van Brocklin, Corvallis, OR (US);
James F Bausch, Salem, OR (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
318471 ; 318268 ; 3889072 ; 388934 ;
Abstract
A controller drives a fan's motor to proportionally control fan speed based on changes in heat output from electrical components in a local environment. The controller is connected to a temperature sensor and the fan motor. The temperature sensor senses local environment temperature, while exhibiting a lag time. The controller provides closed loop control and implements a system pole which cancels out the temperature sensor lag time during steady state operations. The controller implements an integration of a difference between sensed temperature and a reference temperature to generate the system pole.