SU1247681A1 - Digital thermometer - Google Patents

Abstract

The invention relates to the field of temperature measurements and makes it possible to improve the accuracy of temperature measurements. The device contains a thermal converter 1, a converter 2 of a signal into a number of pulses, a programmable binary counter 3, binary counters 4 and 10, a memory device 5, a recording pulse shaper 6, a binary decimal counter 7, a digital display unit 8 and a controlled frequency divider 9. The introduction of new elements and the formation of new connections between the elements of the device allows us to preserve the memory volume of the memory device 5 and simplify the thermometer by excluding the second controlled frequency divider and register from its composition. Gil. with with (L hchz 4iib O) 00

Description

The invention relates to the field of temperature measurements and can be used for accurate temperature measurements with numerical results.

The aim of the invention is to improve the accuracy of temperature measurement while maintaining the memory volume of the permanent storage device and to simplify the thermometer by excluding from its composition the second controlled frequency divider and register.

The drawing shows a block diagram of a digital thermometer.

A digital thermometer contains a thermal converter 1, for example a thermal converter of resistance or a thermoelectric converter, a converter 2 of a signal of a thermal converter into a number of pulses, a program and a binary counter 3, the first binary counter 4, a permanent memory device 6 write pulses, a binary 10th unit 7, block 8 digital display, controlled frequency divider 9 and the second binary counter 10.

Digital thermometer works as follows.

The output signal of the thermal converter is converted in converter 2 into a number of pulses. The pulses from the output of converter 2 are fed through a divider -9 to the input of a binary decimal counter 7. The initial transfer coefficient of the divider 9 is determined by the initial state of the parallel output of the counter 10.. The conversion coefficient of the transducer 2 is chosen so that the total conversion function of the thermometer at the beginning of the measurement range with the permissible error corresponds to the nominal one. As pulses arrive from converter 2, the overall conversion function of the device due to non-linearity of the temperature converter gradually deviates from the nominal one. I

When the error due to this deviation reaches an acceptable value, it is necessary to change the coefficient of transmission of the divider 9.

The change is as follows.

Zero cell of the persistent storage device 5 is written

the number that determines the length of the first part of the approximation to which some initial value of the transfer coefficient of divider 9 corresponds. With a common reset pulse at the moment the digital thermometer is turned on, this number is entered into counter 3, and the count in it starts not with zero, but from this number. Overflow pulse

on the clock input of the counter 3, indicating the beginning of the next section of the approximation, arrives at. the clock input of counter 10 and changes information at its parallel output, and hence the transfer coefficient of divider 9. At the same time, this pulse arrives at the clock input of counter 4, which activates a new memory cell in the permanent memory 5 and, moreover, a delay in the imaging unit 6 — to the input of the record of the counter 3. The counter 3 records a new number corresponding to the length of the next approximation area.

Thus, linearization of the overall conversion function of the digital thermometer occurs.

Claims (1)

Invention Formula A digital thermometer containing a thermal converter connected to the input of a thermal converter's signal converter in the NUMBER of pulses. the output of which is connected to the clock input of the controlled frequency divider and the clock input of the programmable binary counter, whose recording input is connected to the output of the recording pulse generator, the information input is connected to the output of the permanent storage device, and the clock output is connected to the input of the recording pulse generator and input the first binary counter, the output of which is connected to the input of a permanent storage device, a binary-decimal counter, the input of which is connected to the output controlled frequency divider, and the output is connected to the digital display unit, 0 t and h. in order to improve the accuracy of temperature measurement while maintaining the memory capacity of the permanent storage device and simplify the thermometer by excluding the second controlled time divider from it 3112476814 the register and the second binary counter are entered, and the output is connected to a binary counter, the input of which is connected to the control input of the controlled one is connected to the output of the programmable frequency divider.