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Browse Prior Art Database

Variable Air Cooling for Computer And/Or Electronic Equipment

IP.com Disclosure Number: IPCOM000099995D
Original Publication Date: 1990-Mar-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 3 page(s) / 93K

Publishing Venue

IBM

Related People

Torino, AL: AUTHOR

Abstract

This article describes a fan/blower design that incorporates a thermistor within the fan hardware to detect changing air temperature and an amplifier circuit with power and switching so that a resistance threshold is trimmed into the circuit.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Variable Air Cooling for Computer And/Or Electronic Equipment

       This article describes a fan/blower design that
incorporates a thermistor within the fan hardware to detect changing
air temperature and an amplifier circuit with power and switching so
that a resistance threshold is trimmed into the circuit.

      Many personal computers (PCs) with advancing increase in power
will generally use a forced-air cooling fan.  One of the most serious
problems of a PC at "arms length" from an operator is the fan noise
irritation.  This situation is usually in a clean,
well-air-conditioned office environment. However, as the environment
deteriorates, i.e., a factory, the noise problem is secondary to
other background noises. In effect, the scheme disclosed herein is
directed towards providing proper air cooling by varying the fan
speed as the ambient temperature changes.

      The fan/blower disclosed herein provides adequate air cooling
for a variation of environmental conditions.  Noise control and dirt
collection are other effects of this cooling scheme.  The fan motor
is designed with winding taps for multiple speeds.  The circuitry to
switch fan impeller speed is also within the fan housing.

      The equipment design (electronics) is such that at reduced
ambient temperature, i.e., 60-80oF the fan design uses a low speed
with minimum noise.  As the ambient temperature or environment
deteriorates based on customer installation, the fan speed increases.
 This is not a continuous variable speed fan, but preselected speeds.
Also, the poorer environments, i.e., factories, with an increase in
fan speed become noisier but the noise becomes less consequential.
In other word...