SU777456A1 - Ultrasonic level meter - Google Patents

Description

(54) ULTRASOUND LEVEL

The invention relates to a measuring technique, and can be used to measure the level of liquid orfluids in various industrial areas.

- Ultrasonic level gauges containing an acoustic transducer, a generator of excitation pulses, a smart device in which the calibrating channel is designed as an ultrasonic synchro-ring 1 are known.

The reliability of the measurement of the aid of these devices is small, since the frequency of a single pulse of interference from a single pulse of interference, syn., Operating in a sync ring, can double; which leads to false measurements.

Of the known ultrasonic level gauges, the closest to the invention in its technical essence is ultrasound level gauge, containing an acoustic transducer, sequentially connected impulse generator, excitation, radiation detector, blocking element, trigger: p-headlight, time interval 2. - - The disadvantage of the level gauge is not enough noise immunity, so in case of interference, its effect is eliminated only after passing into the synchronicity, as a result of which. ..sboi in indications ypoBHeaiepa, most noticeably n: When high frequency

 ------------- The purpose of the invention is to increase the noise stability of the device.

This is achieved by introducing a controlled one-shot, two electric filters and a second inhibiting element into the gage, with an uniformed one-vibration connected between the excitation reHepaTopa pulp1C01B outputs and the inhibiting input of the first inhibit element, and the control of the one-volt pulse rectifier that is used for the first inhibit element, and the inhibitory input of the first inhibit element is applied to the one-stroke inhibitor, and the restraint signal is applied to the first inhibitory element. 15 are connected in series the first electric filter and. the second prohibition element of the prohibiting entry of which through the second filter is connected to the tsgma ZGHOZHU7R ShM7 sy-Tr11GSC) X

20

The drawing shows a structural diagram of a grinder for each level of the level gauge.

The ultrasonic level gauge contains a generator of excitation pulses, an acoustic transducer 2, in series with a radiation generator / receiver 3 radiation, the first prohibition element 4; trigger forwarder 5. gates and from MeritTel Intervals of time. Level gauge 30 also contains a controlled one-shot 7 connected between the output of the generator / and control of the input of the prohibition element 4, the second prohibition element -8 and the first electrical f, ilt, p 9 connected between the control input 10 of the single-vibration 7 and the trigger output- the driver 5, while the prohibitor input of the prohibition element S through the second electric filter / 2. is connected to the second output 75 of the aforementioned trigger 5. Tpwrreip 5 is equipped with inputs 14 and 15, the input 16 of the one-vibrator 7 is the trigger, and on the output-17 of the one-vibrator is formed | Imp} ls, d Ithel NOSTA which is in the for-linear dependence on the control voltage applied to its input 10.

Works ultrasonic level gauge as follows.

The impulses from the generator / are periodically fed: to the acoustic transducer 2, to the input of the radiation receiver 5, as well as to the input 16 of the single vibrator 7 and the input 14 of the trigger 5. The reflected waves amplified by the receiver 3, through the prohibition element 4 are fed the input 15 of the trigger 5. On The outputs // and J of the trigger thus form strobe pulses, the duration of which is straight. Proportional to the level. The front edge of these pulses coincides in time with the moment of the formation of a pulse of excitement, and the back front coincides with the moment of arrival at the input of the Tripe of the reflected signal.

With the help of the oscillator 7 and the prohibition element 4, the measuring circuit of the level gage is ruptured for some time. The excitation pulse is formed directly. The circuit break time is determined by the duration of the pulse generated by a single vibrator.

For the formation of a positive stress, there are two eloctic filters 5 and / 2 and a prohibition element 8.

In the presence of single impulses at the output of the filter 12, a certain level of Array is formed, sufficient to open the prohibition element 5. In this case, pulses from the // trigger output are passed through the prohibition element, and the output voltage of the filter 9 forms | is controlled, the control voltage, the magnitude of which is directly proportional to the level value.

The magnitude of the control voltage and the parameters of the one-shot 7 should be

They are chosen so that the pulses generated by a single vibrator have a duration somewhat less than the duration of a stand-down pulse. .

In the absence of reflected pulses, output 13 of the trigger 5 is equal to zero. Element 8 is closed, and the control voltage is zero. Thus, at any level value, the measuring level of the level gage opens for a time close to the transit time of the ultrasonic signal from the meter to the interface of the media and vice versa, thereby preventing the triggering

trigger 5 from interference.

The proposed level gauge in comparison with the known is highly resistant. It can maintain the operability of pr, and the presence of impulse noise with

a sufficiently high repetition rate, for example, with interference from ignition of internal combustion engines, and other electrical and acoustic interference.

Ф о у л а and 3 о б shadow

Ultrasonic level gauge containing an acoustic transducer, sequentially calibrated pulse generator

excitation, radiation receiver, prohibiting element, strobe trigger-forming device, and Burden interval meter, due to the fact that, in order to improve noise immunity, a controlled one-shot vibrator, two electric filters and a second prohibition element are inserted, and an adjustable one-shot Included -between the outputs of the excitation pulse generator and the inhibitory input of the first element is broken, and between the control input of the single-pulse and the trigger of the gate-forming gate are connected in series the first electr matic and a second filter element prohibition Inhibit "otorrhea through a second filter connected to the second output of said flip-flop ..

Sources of information taken into account in the examination:

1. USSR author's certificate No. 2i67i3,89, cl. G 01 F 23 / 2-8, 1969.

2. USSR Author's Certificate No. 6341il, 4,, cl. G 01 F, 23/28, 1977.

Claims (1)

Claim An ultrasonic level gauge containing an acoustic transducer, series-connected excitation pulse generator, a radiation detector, a prohibition element, a strobe trigger-shaper, and a time interval meter, in which, in order to increase noise immunity, a controlled one-shot oscillator, two electric filters, and the second element of the ban, and the controlled one-shot is connected between the output of the excitation pulse generator and the inhibit input of the first element of the ban, and between the control input and output monostable triggeraformirovatelya gate connected in series-connected first and second electrical filter element prohibition prohibiting input of which is connected through the second filter to the second output of said latch.