SU773552A1 - Intensity meter - Google Patents

Description

The invention relates to a measurement technique and can be used to measure the intensity of events, in particular, to measure the intensity of impulse irregular flows.

The known devices for measuring the intensity of irregular pulsed flows use the principle 10 of averaging pulses of standard volt-second form (the information is incorporated in the tracking frequency, the period of pulsed flows). At the same time, the random nature of pulsed flows .c forces one to choose a filter time constant much higher than the largest interval of the pulse following, so that the level of ripples of the smoothing voltage does not exceed the admissible 2Qth. However, this drastically reduces the bandwidth of the path, and such devices are not able to detect relatively fast changes in intensity.

A device for measuring the average pulse counting rate is known, which contains a discriminator connected to the intensity meter 1. The output of the intensity meter is connected to the discriminator in such a way that the discriminator threshold changes with an increase in the output signal. Thus, an automatic change in the constant time of the intensity meter is carried out.

A device for measuring the center frequency is known, comprising a driver, a metering element, an integrator in which the Photoresistor of an optoelectronic device is connected parallel to the discharge resistor, the light source of which is connected in series with the metering element in its charge or discharge circuit 2. As the frequency of the pulses increases, the average the current of the driver, while the current of the light source of the optocoupler increases, the photoresistor shunts the integrator discharge resistor. Thus, an automatic change of the integrator time constant occurs with changes in the average frequency.

A famous intensimeter containing a low-pass filter with a large time constant Z.

A disadvantage of the known devices is low speed. In such devices, small changes in the intensity can be very roughly estimated with a small filter constant by the offset of the jitter range of the indicating instrument. But it is impossible to make an unambiguous reading of readings, and even more so it is not possible to use the output voltage of such devices for control purposes due to the high level of ripple. Therefore, filters with a long time constant are used, which allow to obtain a good smoothing of the pulsations. At the same time, control of technological processes requires a high speed of sensors, even information on adjustable parameters.

The purpose of the invention is to increase speed.

The goal is achieved by the fact that the device is additionally equipped with an identifier for the distribution of events, a shaper of the signal polarity, a filter with a short time, two adders, a discriminator, and a time-voltage converter and a storage device, with the transducer controlled by the input pulses , is loaded on the inputs of the first Lilter and the storage device loaded through the first adder on the inputs of the distribution law identifier and the former, whose outputs ryh through the discriminator loaded with the output of the first filter on; the inputs of the second desiccator, the output of which is connected to the output of the device through another filter, loaded also on another input of the first adder.

The drawing shows an intensimeter circuit.

The device consists of a time-voltage converter 1, connected to a filter 2 with a large time constant, and a memory device 3 connected to an adder 4, the second input of which is connected to the output of the intensity meter. The adder 4 is simultaneously connected to the identifier 5 of the event distribution law and to the shaper 6 of the polarity of the signal, which are connected to the discriminator 7. The inputs of the adder 8 are connected to filter 2 and discriminator 7, and the output is loaded on the filter 9 with a small time constant.

This inclusion of the component blocks allows the filter to determine the average value of the pulse pulse interval from a long time constant and, comparing its value with each successive interval / estimate the probability of a change in the intensity of events, as well as make timely correction of the output signal. The estimation of probabilities is performed according to a given (studied

the law of event distribution. In this case, the distribution curve is reconstructed by the event distribution law identifier.

The time-to-voltage converter 1 converts the intervals T of the input pulses into a voltage averaged by the filter 2 for a long constant time. The output voltage of the converter 1 in each cycle is stored by the storage device 3. The adder 4 finds the current value of the difference between the output voltage of the device and

and stress

out

the storage device U 3, applying this difference to the inputs of the identifier 5 of the event distribution law and the driver 6 loaded on the discriminator 7. The identifier 5 estimates the probability of a deviation and the current interval of pulses T from the average by the value and T, -. for some established boundaries of 1 A (corresponding to 2b), the discriminator 7 produces a voltage. If the probability P of occurrence of dT is outside the established limits, then the difference t lA-Pjl, corresponding to the probability of a change in the intensity of events, comes from the output of the discriminator 7 to the adder 8 with an appropriate sign. In this case, the polarity of the signal (opposite to the deviation of l is controlled by the shaper 6. The sum of the current values of the average and differences ± | А-Р 1 is smoothed by the filter 9 with a small time constant. As a result, at a constant intensity of events, the output voltage of the device has a very high small pulsations, slightly increasing only at the moments of intensity change.

Tests of the device show that with the same ripple of the output voltage of the intensity meter, the signal delay of the proposed intensity meter is approximately 15 times less than in the known device. In this case, the desired value of the intensity of events is easily determined from the measured average interval of the trace / T.

mi In particular, in the tested device such dependence is realized by non-linear calibration of the switch instrument for the instrument.

The proposed device can be widely used in nuclear technology, as well as in radioisotope control of the properties of substances and products, where the increase in the speed of the intensity meters actually allows control of production processes and experiments.

Claims (3)

1. Author's certificate of the USSR 252487, class, G 01 T 1/17, 1961. 2. USSR author's certificate number 473188, cl. G 01 T 1/16, 1974. 3. Description of the device 4IO2-2eM. Information sheet V / o Izotop, T-14862, 1974 (prototype).