Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Frost sensor for use in defrost controls for refrigeration

Patent ·
OSTI ID:874815
 [1];  [1];  [1];  [1]
  1. ADA Technologies, Inc. 8100 Shaffer Pkwy., Suite 130, Littleton, CO 80127-4107
+ Show Author Affiliations

An apparatus and method for measuring the total thermal resistance to heat flow from the air to the evaporative cooler fins of a refrigeration system. The apparatus is a frost sensor that measures the reduction in heat flow due to the added thermal resistance of ice (reduced conduction) as well as the reduction in heat flow due to the blockage of airflow (reduced convection) from excessive ice formation. The sensor triggers a defrost cycle when needed, instead of on a timed interval. The invention is also a method for control of frost in a system that transfers heat from air to a refrigerant along a thermal path. The method involves measuring the thermal conductivity of the thermal path from the air to the refrigerant, recognizing a reduction in thermal conductivity due to the thermal insulation effect of the frost and due to the loss of airflow from excessive ice formation; and controlling the defrosting of the system.

Research Organization:
ADA Technologies, Inc., Englewood, CO
DOE Contract Number:
FG03-97ER82309
Assignee:
French; Patrick D. (ADA Technologies, Inc. 8100 Shaffer Pkwy., Suite 130, Littleton, CO 80127-4107); Butz; James R. (ADA Technologies, Inc. 8100 Shaffer Pkwy., Suite 130, Littleton, CO 80127-4107); Veatch; Bradley D. (ADA Technologies, Inc. 8100 Shaffer Pkwy., Suite 130, Littleton, CO 80127-4107); O'Connor; Michael W. (ADA Technologies, Inc. 8100 Shaffer Pkwy., Suite 130, Littleton, CO 80127-4107)
Patent Number(s):
US 6467282
OSTI ID:
874815
Country of Publication:
United States
Language:
English

References (2)

Development of a demand defrost controller. Final report report October 1993
Fiber optic ice sensors for refrigerators conference August 1991

Similar Records

Related Subjects

/62/
added
air
airflow
apparatus
blockage
conduction
conductivity
control
controlling
controls
convection
cooler
cycle
defrost
defrosting
due
effect
evaporative
excessive
fins
flow
formation
frost
heat
ice
insulation
interval
involves
loss
measures
measuring
method
path
recognizing
reduced
reduction
refrigerant
refrigeration
resistance
sensor
thermal
thermal conductivity
thermal resistance
timed
total
transfers
triggers