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AssigneeThe Hetra Corporation
InventorOgden H. Hammond, III
Estimating the term…
The composition of a sample is determined with reference to a recorded standard using the same heater and sensor as that used to record the standard, by testing the sample only when its temperature has reached an equilibrium, and by compensating for differences in environment and starting temperature; accurate heater control is insured by maintaining a constant voltage across a series circuit consisting of a heater and a resistance load equal to the resistance of the heater; the heater is pulsed in an initial test sequence to heat the system to above ambient so that heat losses to the environment are substantially the same from test to test; a dynamic insulation system prevents heat loss from the sample under test; an improved test based on the sensed temperature of the sample immediately after the heater is turned off detects the presence of tungsten forgeries; a compensated infrared sensor eliminates the need for a direct contact temperature sensor; and tests are provided for determining various physical characteristics of an unknown sample.
In a system for determining the thermal characteristics of a sample and for comparing them to the corresponding thermal characteristics of a standard, said system including a heater for applying a heat pulse of finite duration to said sample or said standard and a sensor for measuring the temperature response of said sample or said standard at a plurality of successive instants of time, t.sub.i, following the application of said heat pulse, that improvement comprising:
In a system for determining the thermal characteristics of a sample and for comparing them to the corresponding characteristics of a standard, said system including a heater for applying a heat pulse of finite duration to said standard or said sample at one point thereof and monitoring the temperature vs. time response at a second point thereof at a plurality of successive instants of time, t.sub.i, that improvement comprising:
In the process of determining the thermal characteristics of a material sample in which a heat pulse of finite duration is applied to the sample at a first point and the temperature v. time response of the sample is monitored at a second point spaced from said first point, that improvement wherein:
In a system for determining the thermal characteristics of a material sample including a heater for applying a heat pulse of finite duration to the sample at one point and a sensor for monitoring the temperature v. time response of the sample at a second point, that improvement comprising:
In a system for determining the thermal characteristics of a sample and for comparing them to the corresponding thermal characteristics of a standard, said system including a heater for applying a heat pulse of finite duration to a first point of said standard or said sample and a sensor for measuring the temperature response at a second point of said standard or said sample, a non-alloyed gold forgery detector comprising:
A system for determining the ratio of density (P) to thermal conductivity (R) of a materials sample comprising:
In a system for determining the thermal characteristics of a material sample and comparing them to the corresponding characteristics of a standard and including a heater for applying a heat pulse of finite duration to the standard or sample at one point and a sensor for monitoring the resulting temperature v. time response of the standard or sample at a second point, that improvement including:
Dependencies are inferred from the claim text.