Measurement of delivered thermal units

Apparatus for gauging heat units exchanged by fluid that is moved from an inlet passage to a heat exchange region and thence to an outlet passage, whereby the temperature of the fluid tends to be low in the "low temperature" one of said passages compared to the fluid temperature in the "high temperature" other of said passages, said apparatus including two temperature sensors, one for each of said passages, said apparatus including dual channels each including heat read-out means, electric heating means for said sensors respectively and means for controlling energization of the respective heating means and for providing input to the respective heat read-out, all as aforesaid, for registering heat exchange both when the fluid flow provides heating and when it provides cooling, further including means in each channel rendered operative when its output exceeds a threshold for suppressing operation of at least the heat read-out of the other channel.

Apparatus for gauging the heat units exchanged by a fluid that is moved from an inlet passage to a heat exchange region and thence to an outlet passage, whereby the temperature of the fluid tends to be low in the "low temperature" one of said passages compared to the fluid temperature in the "high temperature" other of said passages, said apparatus including two temperature sensors, one for each of said passages, the sensor for the low-temperature passage having electric heating means, a heat read-out, and means responsive to said sensors for (1) controlling the energization of said electric heating means to raise the temperature of the sensor of the low temperature passage so as to approximate the temperature of the high temperature passage and (2) for correspondingly providing input to said heat read-out, said sensor in the low-temperature passage and said electric heating means constituting a unit, and wherein said unit has heat-exchange characteristics that cause substantial equal dissipation of heat due to changes in the mass-rate of fluid flow and due to changes in the difference in temperature between that of the low-temperature passage and that of the sensor in the low-temperature passage for representing the energy change of the fluid between the inlet and outlet passages.

A method of gauging heat units exchanged between heat exchange means and a fluid that is moved from an inlet passage through a heat exchange region and thence to an outlet passage, including the steps of disposing a temperature sensor in the high-temperature one of said passages, disposing a sensor/resistor unit in the low-temperature one of said passages so as to be surrounded by the fluid therein, said sensor/resistor unit comprising a temperature sensor and a resistor in intimate heat-transfer relation to each other, detecting a difference that occurs at times in the response of said sensors, utilizing the detecting difference to determine the supply of energy to the resistor of said sensor/heat unit for maintaining the sensor of that unit at a close approximation of the temperature of the sensor in the high temperature passage, and indicating the energy thus supplied to the resistor as a representation of the heat exchanged in said heat-exchange region.

A method for gauging the heat units provided by a fluid that is moved from an inlet passage to a heat exchange region and thence to an outlet passage, whereby the temperature of the fluid tends to be low in the "low temperature" one of said passages compared to the fluid temperature in the "high temperature" other of said passages, said apparatus including two temperature sensors, one for each of said passages, the sensor for the low-temperature passage having electric heating means, a heat read-out, and means responsive to said sensors for (1) controlling the energization of said electric heating means to raise the temperature of the sensor of the low temperature passage so as to approximate the temperature of the high temperature passage and (2) for correspondingly providing input to said heat read-out, the heated sensor in the low-temperature passage having characteristics causing it to respond proportionally to changes in heat content of the moved quantity of fluid independent of whether the changes of heat content are due to changes of temperature difference between the inlet and outlet passages or to changes in the rate of mass-flow of the fluid.

In a system having an inlet passage, an outlet passage, a heat exchange region between said inlet and outlet passages, and means for moving fluid successively through said inlet passage, said heat exchange region, and said outlet passage, whereby the temperature of the fluid tends to be lower in the "low temperature" one of said passages than in the other one of said passages, said means having operation-interrupting means, and apparatus for gauging heat units exchanged between said fluid and said heat exchange means, said gauging apparatus including a temperature sensor for each of said passages, a heating resistor in heat-transfer relation to the sensor in said low temperature passage, a heat read-out, and means responsive to said sensors for (1) controlling energization of said heating resistor to raise the temperature of the sensor of the low-temperature passage to approximate the temperature of said other one of said passages and (2) for correspondingly providing input to said heat read-out, said system including means for suppressing entry of said input into said heat read-out in coordination with interruption of the operation of said fluid-moving means.