SU648844A1 - Radio-wave level meter - Google Patents

Description

one

This invention relates to instruments used to measure the level of liquids and solids.

Level gauges are known that use two-wire and coaxial sensors and measure the level by tracking a standing wave node as the line lengths change.

The disadvantage of these devices is the low measurement accuracy.

The closest in technical essence to the present invention is a radio wave level gauge comprising a generator, feeder guides, radiating and receiving antennas, a measuring line, a probe, installed at distances corresponding to the wavelength of the 2J generator.

The disadvantages of this device are large inertia and unreliability in operation.

The purpose of the invention is to improve the dynamic performance and increase the reliability of the device.

This goal is achieved by the fact that, in a radio wave level gauge, the probes are connected in series through amplitude-code transducers with remote control and indicator lamps,

FIG. 1 shows the structural scheme of the proposed device; in fig. 2 - electrical schematic diagram of the amplitude-code converter on the logical elements of IS-NOT; in fig. 3 is a diagram of the stress in the probes), varying in the bridge depending on the material level (one division corresponds to 25 cm), and the coordinate grid, with which the threshold values of the amplitude-code transducers are set.

The device contains a high-frequency generator 1, a feeder line 2, a two-conductor line 3, probes 4 installed along the feeder line at a distance; fugs from each other (l./6 + nl), where d is the length; ra wave, rt 1.2,3 ,, .. - coefficient.

chosen from constructive considerations, am 1 out of two code converter 5, a diode decoder 6 indicator lines 7, and a clear fire capacitance 8.

Amplitude coded, the transducer is a codofi device that has an ODEL input and H outputs corresponding to the number of levels of quantization in the Md, Is and TG,.

The principle of operation of the radio waveguide is the following.

From generator 1, the high-frequency signal enters through the feeder line 2 to the two-way & amphibious line 3, which is lowered into the process tank 8. When the material level changes, the phase of the reflected signal also changes in the feeder-line, where the standing wave mode is formed, the inte- gratic shift occurs. the flow pattern is proportional to the level being measured. The signals in probes 4 are a function of the measured material level.

The inputs of the voltage converter are supplied from the probes 4 through dividers.

In the absence of an input signal, logical b are set at all outputs of the converter. As the voltage on one and the outputs of the converter increases, logical 1 appears; bovremenyo on the other outputs of the converter

logical O are set. The signal from the output of amplitude-code converters is fed to the input of the decoder 6 of the corresponding bit. The number of channels of the decoder is determined in the general case by the number of indices required for the indicator, which depends on the calibration of the device.

Claims (2)

1. Iordan G. G. et al. Instruments for the automatic control and regulation of technological processes based on radio-ultrasonic, ultrasonic and radio wave methods, Instruments and automation equipment, No. Yu 1961. 2. USSR author's certificate No. ZO1548, cl. Q O1 p 23/28, 197O. L .J 8 1 g 4 5 6 7 8 ff fff 77/2 / J HaftfjAUfnydfO -aaffe ffhiH npfaffn / i nStyfnf tfl .З / "75 fff 17