Humidity sensor using temperature sensing resistor controlled to be at constant temperature of more than 150.degree. C.
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Nov 17, 1998
Grant Date -
N/A
app pub date -
Aug 23, 1996
filing date -
Dec 29, 1994
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
A humidity sensor of a heat conduction type which enables a humidity measurement to be produced by a single temperature sensing resistor so as to reduce a change in characteristic depending on a temperature change of the measurement atmosphere and to reduce the cost, comprises a temperature sensing resistor 1 and three fixed resistors R.sub.1, R.sub.2 and R.sub.3 which form a Wheatstone bridge circuit. The humidity is measured by utilizing the fact that the heat dissipation of the temperature sensing resistor 1 changes depending on the humidity. The temperature sensing resistor 1 is heated by a heat generator 2 for self-radiation of Joule heat so that the temperature of the temperature sensing resistor 1 is controlled to be at a constant temperature of 150.degree. C. or more. The output voltage value of the Wheatstone bridge circuit is corrected with reference to the variation of the output voltage value depending on the ambient temperature of the temperature sensing resistor 1.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully