SU572662A2 - Device for measuring and indicating temperature variation rate - Google Patents

Description

one

This invention relates to the field of contact thermometry.

A device is known for measuring and signaling the rate of change in temperature according to the authors. swith No. 528459, containing a thermocouple connected through a DC amplifier to the gates of a dual metal oxide semiconductor transistor (MOS transistor), one of which is switched by a key to which the storage capacitors are connected, and the drain resistors between which are connected The input of a two-square controlled frequency generator is switched on, the output of which is connected to the electronic key control circuit.

A disadvantage of the known device is low sensitivity due to the direct connection of the output of the generator to the control circuit. with an electronic key and, accordingly, a finite frequency of switching the key at a constant heating rate equal to the generator frequency.

To increase the sensitivity, the pre-tagged device has a frequency divider, the input of which is connected to the output of the controlled frequency generator, and the output is connected to the control circuit of the electronic key.

The drawing shows the scheme of the described device containing a thermocouple 1 connected to a DC amplifier 2, a dual MOS transistor 3, memory capacitors 4, 5, an electronic switch 6, load resistors 7 and 8, a linear generator 9 controlled frequency, additional outputs 10, 11 of the generator 9 and the divider 12 frequency.

The device works as follows.

The pa outputs of the differential stage, made on a dual MOS transistor, are fed through a thermoelectric amplifier 2. a. s., developed by thermocouple 1. Capacitors 4 and 5 carry out operational memorization of information. At zero voltage at the input of the generator 9, its frequency is zero, which corresponds to the equality of the voltages on the storage capacitors 4, 5 and, accordingly, to the zero rate of temperature change. The switching frequency of key 6 is also zero. The occurrence of voltage at the output of the differential stage indicates the difference in voltage across the storage capacitors 4, 5, causes a change in the frequency generated by the generator 9 and changes the switching frequency of the electronic key B

Thus, the linear oscillator of the controlled frequency changes its frequency so as to eliminate the differential voltage between the drain of the MOS transistor and maintains them in the same modes. The switching frequency of the electronic key is

where n is the capacitance of the divider 12 frequency.

In addition to the main output controlling the operation of the electronic key 6, the frequency controlled oscillator has two additional outputs 10, I. The appearance of pulses at output 10 or 11 is determined by the sign of the generator input voltage and depends on the sign of the rate of temperature change. Output frequency RVSh

devices are linearly related to the rate of temperature change.

Introducing a frequency divider into the circuit of a device increases the sensitivity of the device by a factor of n, which makes it possible to expand its scope by using i.

Claims (1)

Invention Formula A device for measuring and signaling the rate of temperature change according to the author. swith No. 528459, which means that, in order to increase the sensitivity, a frequency divider is inserted in it, the input of which is connected to the output of the controlled frequency generator and the output connected to the control circuit of the electronic key.