SU773455A1

SU773455A1 - Temperature measuring apparatus

Info

Publication number: SU773455A1
Application number: SU792758666A
Authority: SU
Inventors: Валентин Леонидович Славинский; Александр Григорьевич Радченко
Original assignee: Всесоюзный Заочный Политехнический Институт
Priority date: 1979-04-27
Filing date: 1979-04-27
Publication date: 1980-10-23

Description

1one

Изобретение относитс к термометрии .This invention relates to thermometry.

Известно устройство дл измерени температуры, содержащее источ- 5 ник питани , термочувствительный резистор, интегратор, ключ, нульорган , блок индикации 1.A device for measuring temperature is known, comprising a power supply, a temperature-sensitive resistor, an integrator, a key, a nuorgan, a display unit 1.

Недостаток этого устройства заключаетс в том, что на точность 10 измерени оказывает существенное вли ние нестабильность питеиощего напр жени .The disadvantage of this device is that the accuracy of the measurement 10 is significantly affected by the instability of the drinking voltage.

Наиболее близким по технической сущности к предлагаемому вл етс 15 устройство дл измерени температуры , содержащее источник питани ,соединенные последовательно электронный ключ, термочувствительный резистор , интегратор, нуль-орган, второй 20 электронный ключ и счетчик импульсов , выходы которого подключены к блоку цифровой индикации, ко второму входу первого электронного ключа и ко входу третьего электронного 25 ключа, подсоединенного к интегратору , причем выход генератора тактовых импульсов подключен ко второму входу счетчика импульсов,а выход генератора образцовой частоты подсоеди- ЗОThe closest in technical essence to the present invention is a temperature measuring device 15 comprising a power source, an electronic key connected in series, a temperature-sensitive resistor, an integrator, a zero-organ, a second 20 electronic key and a pulse counter, the outputs of which are connected to a digital display unit the second input of the first electronic key and the input of the third electronic 25 key connected to the integrator, the output of the clock generator connected to the second input of the counter mpulsov and oscillator output reference frequency LP Connecting cable

йен ко второму входу электронного ключа (2.yen to the second input of the electronic key (2.

Однако в этом устройстве к питающему напр жению предъ вл етс требование высокой и долговременной стабильности, что ведет к снижению точности измерени и усложн ет устройство .However, in this device, the supply voltage requires high and long-term stability, which leads to a decrease in measurement accuracy and complicates the device.

Целью изобретени вл етс повышение точности измерени .The aim of the invention is to improve the measurement accuracy.

Цель достигаетс тем, что в устройство введен эталонный резистор, включенный в рассечку между третьим электронным ключом и входом интегратора , причем входы первого и третьего ключей подсоединены к отрицательному и положительному выводам источника питани соответственно .The goal is achieved by introducing a reference resistor in the device, which is included in the split between the third electronic key and the integrator input, and the inputs of the first and third keys are connected to the negative and positive terminals of the power supply, respectively.

На фиг. 1 представлена блок-схема устройства; на фиг. 2 - временные диаграммы, по сн юише работу устройства .FIG. 1 is a block diagram of the device; in fig. 2 - timing diagrams, according to the device operation.

Claims

The device contains a pulse counter 1, a generator of 2 clock pulses, a first electronic switch 3, an integrator 4, a source of 5 negative voltage polarity, a temperature-sensitive resistor 6, a null-organ 7, a generator 8 of exemplary frequency, the second and third electronic switches 9 and 10, positive-polarity supply voltage source 11, reference resistor, 12, digital display unit 13 The device operates as follows. In the first integration cycle, the output switch is connected to the input of the integrator 4 via the first electronic switch 3 supply point of negative polarity 5 and thermo-sensitive resistor b, and in the second integration cycle, the output of source 11 of the supply voltage of positive polarity and reference resistor 12 is connected to the input of integrator 4 via a third electron is reset to the initial state by a pulse emitted by the generator 2 clock pulses. In this case, from the counter 1 pulses, a voltage is supplied to the electronic switch 3, which connects source 5 and a temperature-sensitive resistor 6 to integrator 4. The voltage at the output of integrator 4 increases according to the law and -t iv -i — the resistance of the temperature-sensitive resistor; C is the capacitance of the integrator coupling capacitor; tl is the supply voltage of negative polarity. At the time of going through zero, the zero-organ 7 triggers and the pulses from the generator 8 of the exemplary frequency through the second electronic key 9 are applied to the counting input of the counter 1 pulses, at the moment of overflowing which the voltage (1) reaches its maximum value. , in-max. R oh. In this case, the output signal of the pulse counter 1 closes the third electronic key 10. The first integration cycle ends there. The voltage at the output of the integrator, increased to the maximum value (2), will decrease with a constant speed determined by the value of the resistance of the reference resistor Rjf. those. Yat is a scale factor. The time during which the voltage at the output of the integrator 4 varies from the maximum value to zero, i.e. the measurement time is determined by etMbv Un + Intmax, (3 de Uj, - supply voltage of positive polarity. The moment when the output voltage of the integrator 4 passes through zero, the ul-organ closes the electronic key. By this time the pulse counter 1 receives from the generator 8 the educational frequency, the number of pulses, which is proportional to the measured temperature n, NT mum and. -V., a scaling factor .F is the factor, F is the frequency of the generator of the reference frequency. ° - the conductivity of the thermosensitive resistor. to power supply its voltage requires only short-term stability at the time of integration, as can be seen from formula 4. The absence of a stabilizer in the proposed device allows to simplify it and reduce power consumption. In addition, the manufacture of reference resistors is much simpler than the manufacture of precision power sources. The device for measuring temperature, containing a power source, an electronic switch connected in series, a temperature-sensitive resistor, an integrator, a zero-organ, W swarm electronic key and pulse counter, the outputs of which are connected to a digital display unit, to the second input of the first electronic key and to the input of the third electronic key connected to the integrator, the output of the clock generator connected to the second input of the pulse counter, and the generator output of the reference frequency Connected to the second input of the electronic key, characterized in that, in order to improve the measurement accuracy, a reference resistor is inserted in the device, which is included in the dissection between the third with a given key and an integrator input, with the inputs of the first and third keys connected to the negative and positive terminals of the power source, respectively. Sources of information taken into account during the examination 1. USSR author's certificate No. 502237, cl. G 01 K 7/16, 04.02.74.

2. Martyashin A.I. and others. Electrical parameter converters for the monitoring and control system. M., Energie, 1976, p.56 (prototype). ".". J ..-. T

Ut ffTrf I ti / a "m" o "c - 2l5" a