SU823898A1 - Device for measuring surface temperature - Google Patents

Description

(54) DEVICE FOR MEASURING SURFACE TEMPERATURE

with the input of the analog key and the nullorgan / connected to the logic unit, the outputs of which are connected to the integrator control input, the drive of the supply of the thermal sensor and the control input of the counting unit, the input of which is connected by a sensor of the contact of the thermal sensor and the control input of the analog key.

The drawing shows a block diagram of the device.

The device for measuring the surface temperature contains a semiconductor thermal sensor, such as a transistor 1, placed in the initial state in a thermostat 2 and connected to the input of the measuring circuit 3, a drive 4 for supplying the thermal sensor to the monitored surface, a sensor 5 of contact of the thermal sensor with the monitored surface, zero organ 6 whose output is connected to the input of logic device 7, analog switch 8, integrator 9, comparison unit 10, reference voltage source 11, counting unit 12.

The device works as follows.

In the initial state, the temperature of sensor 1 is equal to the set / determined by thermostat 2. At the output of measuring circuit 3, the signal is zero, at the output of zero-organ 6 there is an enable signal, which corresponds to the steady state of thermal sensor 1 and the readiness of the device for measurement. The zero-body 6 permits the logic unit / switching on the device for measurement on a trigger signal. At the same time, the integrator 9, the counting unit 12 is reset to the initial one for measuring the state, and the logic unit 7 switches on the drive 4 ,. which transfers the thermordatch 1 from the thermostat 2 to the controlled surface of the heated body. When the temperature sensor touches the monitored surface, the contact sensor 5 is turned on, which simultaneously opens the analog key 8 and starts the counting unit 12. The latter starts counting the time, and the integrator 9 - summing the output signal of the measuring circuit 3i When the output of the integrator 9 reaches the voltage value determined by the reference the voltage source of the reference voltage, the comparison unit 9 stops the counting unit 12 and resets the logic unit 7. In this case, the actuator 4 removes the thermal sensor from the monitored surface type in thermostat 2. The contact sensor 5 is disconnected, the analog switch 8 is closed, disconnecting the input of the integrator 9 from the measuring circuit; After cooling the sensor 1 in the thermostat 2 to a predetermined initial temperature at the outlet of the zero-organ 6,

signal allowing the next measurement cycle.

The presence of a thermostat in the device ensures a constant initial temperature of the thermal sensor, so it is possible to control the surface temperature of heated bodies in the initial part of the heating curve. In this case, the duration of the measurement cycle is reduced, namely, the measurement time is halved, the cooling time of the temperature sensor is reduced several times due to forced cooling in the thermostat. In addition, the device eliminates the possibility of the sensor failing due to overheating, since the measurement ends at a temperature several times lower than the maximum permissible temperature sensor.

The presence of new elements in the device, the thermostat, the integrator, the comparator unit, the logic unit, distinguishes it favorably from the known Device, so as it can significantly reduce the duration of the measurement cycle, reduce the amount of heating of the sensor.

Claims (2)

1. Author's certificate of the USSR I 149913, cl. G fll K 7/02, 1962. 2. USSR author's certificate No. 283632, C. 01 K 7/02, 1968 (prototype