PL112088B1 - Method and system for changing sensitivity of a transducer of frequency into voltage or current signals - Google Patents

Description

Published on: 12/30/1981 112088 Int. Cl2. G01R 23/06 Inventors: Michal Smogór, Bogdan Adamczak Authorized by the patent: Osrodek Badawczo-Rozwojowy Pojazdów Szynowych, Poznan (Poland) Method and system for changing the sensitivity of the frequency-voltage or current converter 1 The object of the invention is the method and system for changing the sensitivity of the frequency converter - voltage or current for the automatic detection of the preset frequency threshold of the measured waveform and the corresponding step change in the sensitivity of the transducer.

The known method of changing the sensitivity of the converter frequency-voltage or current is based on a manual step or smooth change of the corresponding electrical parameters of the processing system. This creates great difficulties and eliminates the use of such a converter even in the case of quasi-static changes in the frequency of the waveform, exceeding the selected thresholds - the sensitivity sub-ranges.

The method according to the invention consists in measuring the frequency of the input pulses and, as a function of the frequency of this waveform, controlling the unit switching the parameters of the processing circuit.

The essence of the system according to the invention consists in the fact that the generatormonostabimy, controlled by the input wave, is connected in parallel with meters, one of which is connected via a memory with a switch.

The solution according to the invention is to provide the transducer with any number of sub-ranges limited only by the measurement needs. The permissible rate of change of the frequency of the tested waveform depends only on the parameters of the processing system. The transducer sensitivity is changed automatically, which allows to increase the accuracy of the measurement in the selected ranges of the input frequency.

The invention is explained in more detail in the embodiment example shown in the drawing, which is a block diagram of a circuit for changing the sensitivity of the transducer.

Under the influence of input pulses of frequency fi, the input circuits l £ fgenerate three different sequences of pulses with appropriately selected parameters.

Each of the aforementioned sequences is led to the switch t, which directs the switching of the binary constants, to the processing system 7. The selection of the appropriate connection combination: input circuit - processing circuit, is performed as a function of frequency by the circuit detecting exceeding the assumed frequency thresholds fit, from an inonoctable generator, counters 3 ^, 4 and Smell. of memories 5 and * The detection circuit acts on the switches in such a way that, as a result of this operation, a connection appropriate for a given frequency is made: input circuit - converter circuit. SiJfb counters of capacities L and L are reset to zero by a 2-way input waveform. When during one cycle of the monostabim generatorL the capacity of a counter, for example, counter 3 is exceeded, the overflow impulse writes this information into the memory 5. The memory, in turn, causes a burst of iirn 6. The second counter 4, after a specified time, is memory 3, if the message o appears in the data; 3 112 0 ** 4 If the message appears, the time of memory reset 5 is delayed in time so that the date of the switch 6 is not changed. The process of resetting the memory 5 after the elapse of a certain selected time period & t is of particular importance in the case of oscillating changes in the frequency fk around the switching value. Functions fulfilled by elements 3 ^ 4 ^ 5'sa identical to elements 3, 4, 5. Due to the cascade connection of the counters 4 and 4? A in the output of the numerator4 *, there will be information about exceeding the frequency L XE greater than the frequency corresponding to the previous clause - Patent coverage l. Method of changes \ sensitivity of the converter, frequency, voltage or current, characterized by the fact that the frequency of impulses in the nucleus is measured and, depending on the frequency of this wave, the unit that switches the parameters of the processing system is controlled by sequentially connecting the frequency-processing system to the rectangular input or direct currents ,, the number of which is consistent with the assumed number of sub-ranges. 2. The circuit for changing the sensitivity of the converter frequency - the voltage or current, in which the input circuits are connected to the processing circuit, means that it includes a circuit detecting the exceeding of complex frequency thresholds, in which the generator monosta- Diin v (2), controlled by the input waveform , is connected in parallel with the counter (3) and the second counter (4), the second counter (4) being connected via the memory (5) to the control input of the switch (6).

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