RU113012U1 - ULTRASONIC FLOW SPEED METER - Google Patents

Abstract

An ultrasonic flow rate meter containing three measuring bases, including two reversible electroacoustic transducers, located at an angle of 120 ° relative to each other and at an angle of 30-60 ° in the vertical plane, as well as a switch to which the transmitter and receiver of pulse signals are connected, three comparator, four flip-flops, a node for extracting the third period of sinusoids, a matching device, a counter, a key device and a series-connected time interval-to-digit converter, a division unit, a subtraction unit and a computing device, while the output of the matching device is connected to the input of the third comparator, the output of which is connected to the first input of the counter, the output of the counter is simultaneously connected to the second input of the key device and to the first input of the fourth flip-flop, the output of which is connected to the second input of the counter, the inputs of the first and second comparators are connected to the switch, the output of the first comparator is connected to the first input of the th trigger, the output of the second comparator is connected to the first input of the third-period selection unit of sinusoids, the output of the first trigger is connected to the second input of the third-period selection unit of sinusoids, the output of which is connected to the second inputs of the first, second, third and fourth flip-flops, and the first input of the third trigger is connected to the switch, the output of the third trigger is connected to the first input of the key device, the output of which is connected to the first input of the second trigger, and the output of the second trigger is connected to the time interval-to-digital converter, characterized in that it is supplemented with a synchronization device�

Description

The proposed utility model relates to instrumentation, namely, to a technique for measuring wind parameters, in particular for measuring horizontal wind speeds and directions, as well as the vertical component of wind speed and can be used at airports to ensure aircraft flight safety.

Currently, in the practice of meteorological support for aviation flights, wind parameters sensors, both rotorcraft and acoustic anemometers, are widely used.

Rotorcraft sensors are widely used in domestic and foreign practice, in which wind sensors are used that determine the wind speed by the angular speed of rotation, and the direction - by the location of the turntables along the wind direction due to the presence of weathercocks [1, 2, 3].

At present, they began to use acoustic anemometers for measuring wind speed and its directions [4], which have an advantage, since do not contain mechanically rotating elements (turntables and weathercocks), the presence of which greatly reduces the reliability of wind speed meters and its directions.

The disadvantages of the known technical solutions include the impossibility of measuring the vertical component of the wind speed, which can lead to more complicated landing conditions for aircraft.

Known ultrasonic meter of pulsating flow rates [5], containing two reversible electro-acoustic transducers connected through a switch to a transmitter and a receiver of pulse signals, a time interval digital digit, the output of which through a division block is connected to the first subtraction unit, a synchronizer and a recorder.

The disadvantages of the known meter include its limited capabilities, because it is intended only for measuring wind speed, and parameters such as wind direction and the vertical component of the wind cannot be measured.

Known ultrasonic flow velocity meter [6], which contains three channels for measuring wind speed I, II and III.

Each of the channels for measuring wind speed includes two reversible electro-acoustic transducers connected through a switch to a transmitter and a receiver of pulse signals, a time-to-digital converter, the output of which through a division block is connected to a subtraction block.

The outputs of the subtraction block of each measurement channel are connected to a computing device.

The electro-acoustic transducers of each channel for measuring wind speed form three measuring bases located at the same distance L at an angle of 120 ° relative to each other and at an angle of (30-60) ° in the vertical plane.

The disadvantages of the known flow velocity meter include the low accuracy of measuring the horizontal and vertical components of wind speeds and wind direction.

Known ultrasonic flow velocity meter [7], containing three channels for measuring wind speed, each of which includes two reversible electro-acoustic transducers connected through a switch to a transmitter and a receiver of pulse signals, a time-to-digital converter, the output of which through a division block is connected to a subtraction unit while the outputs of the subtraction blocks of all three channels for measuring wind speed are connected with a computing device, and the electro-acoustic transducers of each channel are measured Grains of wind speed form three measuring bases located at an angle of 120 ° relative to each other and at an angle of (30-60) ° in the vertical plane.

Each of the three channels for measuring wind speed is supplemented by two comparators, three triggers and a selection unit for the third sinusoid period, while the inputs of the comparators are connected to the switch, the output of the first comparator is connected to the first input of the first trigger, the output of the second comparator is connected to the selection unit of the third period of the sine wave, output the first trigger is connected to the second input of the selection node of the third period of the sine wave, the output of which is connected to the second input of the second trigger, to the second input of the first trigger and to the second the input of the third trigger, in addition, the first input of the third trigger is connected to the switch, and the output of the third trigger is connected to the first input of the second trigger, and the output of the second trigger is connected to the time-to-digital converter.

The disadvantages of the known ultrasonic flow velocity meter include a significant dependence of the accuracy of the measurements on the technological variation of the parameters of electro-acoustic transducers.

The closest technical solution to the proposed utility model is an ultrasonic flow velocity meter [8], containing three channels for measuring wind speed, each of which includes two reversible electro-acoustic transducers connected through a switch to a transmitter and receiver of pulse signals, two comparators, the inputs of which are connected to the switch, three flip-flops and a selection node of the third period of the sine wave, while the output of the first comparator is connected to the first input of the first trigger, the output of the second the mparator is connected to the first input of the selection node of the third period of the sine wave, the output of the first trigger is connected to the second input of the selection of the third period of the sine wave, the output of which is connected to the second input of the second trigger and the second input of the third trigger, the first input of the third trigger is connected to the switch, the output of the second trigger connected to a time-digital time converter, the output of which through the division block is connected to the subtraction block, the outputs of the subtraction blocks of all three channels for measuring wind speed are connected to a calculating device, and the electro-acoustic transducers of each channel for measuring wind speed form three measuring bases located at an angle of 120 ° relative to each other and at an angle of (30-60) ° in the vertical plane.

Each of the three channels for measuring wind speed is supplemented by a sequentially connected matching device, a third comparator and counter, a fourth trigger and a key device, while the output of the counter is simultaneously connected to the second input of the key device and the first input of the fourth trigger, the output of which is connected to the second input of the counter, and the second input is connected to the output of the allocation node of the third period of the sine wave, the first input of the key device is connected to the output of the third comparator, and its output to the first input the second trigger, the input of the matching device is connected to the first input of the third comparator.

The disadvantages of the known ultrasonic flow velocity meter include low reliability (probability of failure-free operation), manufacturability and increased material consumption and power consumption, which is due to the significant number of active devices in each measurement channel. This circumstance leads to manufacturing complexity, increased mass-dimensional indicators, which increases the cost of an ultrasonic flow velocity meter.

The increased mass-overall dimensions and energy consumption limit the possibility of using such devices in portable and automatic weather-powered stations.

The main task, which the utility model is aimed at, is to increase reliability, manufacturability and reduce material consumption and energy consumption.

The problem is solved using the proposed ultrasonic flow velocity meter, which, like the prototype, contains three measuring bases, including two reversible electro-acoustic transducers located at an angle of 120 ° relative to each other and at an angle (30-60 °) in the vertical plane, and a switch to which a pulse signal transmitter and receiver are connected, three comparators, four triggers, a third-period sine wave allocation unit, a matching device, a counter, a key device and a sequence the time-to-digital converter, the division unit, the subtraction unit, and the computing device, the output of the matching device is connected to the input of the third comparator, its output is connected to the first input of the counter, the output of the counter is simultaneously connected to the second input of the key device and to the first input of the fourth a trigger whose output is connected to the second input of the counter, the inputs of the first and second comparators are connected to the switch, the output of the first comparator is connected to the first input of the first trigger , the output of the second comparator is connected to the first input of the selection node of the third period of the sine wave, the output of the first trigger is connected to the second input of the selection of the third period of the sine wave, the output of which is connected to the second inputs of the first, second, third and fourth triggers, and the first input of the third trigger is connected to the switch , the output of the third trigger is connected to the first input of the key device, the output of which is connected to the first input of the second trigger, and the output of the second trigger is connected to the time interval converter -tsifra.

Unlike the prototype, the ultrasonic flow velocity meter is supplemented by a synchronization device, a logical adder and six keys, two in each measuring base, while the first input of each key is connected to the output of the corresponding acoustic transducer of its measuring base, the outputs of the keys, the inputs of which are connected to the first electro-acoustic the transducers of each measuring base are simultaneously connected to one input of the switch, the outputs of the keys, the inputs of which are connected to the second electroacoustic transducers of each measuring base are connected to another input of the switch, the second key inputs of the first measuring base are connected to the first output of the synchronization device, the second key inputs of the second measuring base are connected to the second output of the synchronization device, the second key inputs of the third measuring base are connected to the third output of the synchronization device , the first, second and third inputs of the logical adder are connected to the corresponding outputs of the synchronization device, and its output is simultaneously under keyed to the switch and computing device.

The essence of the proposed utility model is that, thanks to the introduction of a synchronization device, a logical adder and six keys (two in each measuring base), a significant (3-fold) reduction in the number of active devices in this model was achieved, which significantly increased the probability of failure-free operation and manufacturability, reduced time and material costs (therefore, cost), weight and power consumption of the device while maintaining all the functions and advantages of the prototype.

In addition, the presence of only one transmitter for working with all electro-acoustic transducers provided the same conditions for their excitation and, therefore, obtaining a smaller difference in the electromechanical characteristics of these electro-acoustic transducers, which also improves the accuracy and stability of measurements.

The proposed utility model is illustrated in the drawing, where in Fig.1 - shows a functional diagram of an ultrasonic flow velocity meter;

figure 2 - timing diagrams of the interaction of nodes.

The ultrasonic flow velocity meter contains three measuring bases I, II and III, each of which includes two reversible electro-acoustic transducers 1 _I and 2 _I , 1 _II and 2 _II , 1 _III and 2 _III , connected via keys 3 _I and 4 _I , 3 _II and 4 _II , 3 _III and 4 _III and through the switch 5 to the transmitter 6 and receiver 7 of the pulse signals, the first comparator 8, the second comparator 9, the first trigger 10, the allocation unit of the third period of the sine wave 11, the second trigger 12, the third trigger 13, serially connected matching device 14, third comparator 15 and counter 16, fourth th trigger 17, the key device 18, connected in series converter timeslot-figure 19, dividing unit 20, subtracting unit 21 and computing device 22 whose first output synchronization unit 23 is connected to the second inputs of the keys 3 _I and 4 _I, a second output is connected to the second inputs of the keys 3 _II and 4 _II , and the third output is connected to the second inputs of the keys 3 _III and 4 _III , as well as the logical adder 24.

Electro-acoustic transducers are located at the same distance L at an angle of 120 ° relative to each other and at an angle of (30-60) ° in the vertical plane.

The inputs of the first comparator 8 and the second comparator 9 are connected to the switch 5, the output of the first comparator 8 is connected to the first input of the first trigger 10, the output of the second comparator 9 is connected to the first input of the selection node of the third period of the sine wave 11, the output of the first trigger 10 is connected to the second input of the selection node the third period of the sine wave 11, the output of which is connected to the second input of the second trigger 12, to the second input of the first trigger 10, to the second input of the third trigger 13 and to the second input of the fourth trigger 17, in addition, the first input q of the third trigger 13 is connected to the switch 5, and the output of the third trigger 13 through the key device 18 is connected to the first input of the second trigger 12, and the output of the second trigger 12 is connected to the time-to-digital converter 19 and to the input of the synchronization device 23, and the output of the counter 16 simultaneously connected to the second input of the key device 18 and to the first input of the fourth trigger 17, the output of which is connected to the second input of the counter 16, and the input of the matching device 14 with the first input of the third trigger 13, the first, second and the third inputs of the logical adder 24 are connected to the corresponding outputs of the synchronization device 23, and its output is connected simultaneously with the switch 5 and the computing device 22.

Ultrasonic flow velocity meter works as follows.

At the beginning, the synchronization device 23 at its outputs sequentially, starting from the first, generates control signals , and (see figure 2), which are sequentially fed to the 1st, 2nd and 3rd inputs of the logic adder 24 and to the second inputs of each key pair 3 _I and 4 _I , 3 _II and 4 _II , 3 _III and 4 _III , connecting pairs of electro-acoustic transducers 1 _I and 2 _I , 1 _II and 2 _II , 1 _III and 2 _{III of the} corresponding measuring base I, II and III to the switch 5.

From the output of the logical adder 24, the signals U ₂₄ , generated in the same sequence as at the outputs of the synchronization device 23, are fed to the switch 5 and to the computing device 22, preparing them for measurements in series with each measuring base I, II, and III. In this case, as will be shown below, the duration of the signals from the outputs of the synchronization device 23 and the logical adder 24 corresponds to the duration of the cycle of work on radiation and reception in both directions for each measuring base I, II and III.

Switch 5 for enable signal , and from the output of the logical adder 24, alternately connects the transmitter 6 and receiver 7 to the electro-acoustic transducers 1 _I and 2 _I , 1 _II and 2 _II , 1 _III and 2 _{III of the} selected measuring base I, II or III, ensuring the operation of these electro-acoustic transducers to radiation and reception in the forward and reverse directions.

In this case, the beginning of the emitted pulse U ₆ starts the third trigger 13, the signal U _{13 of} which is supplied to the first input of the closed key device 18.

At the same time, the emitted pulse U _{6 is} supplied to the input of the matching device 14, which selects the sinusoidal component of the generation pulse U ₁₄ , which is fed to the input of the third comparator 15, which has a response threshold U _n = 0, which ensures accurate fixation of the beginning of the period of the sinusoidal component of the emitted signal U _6.

Next, the output pulse U _{15 of the} third comparator 15 is fed to the input of the counter 16, which generates an output signal U ₁₆ corresponding to the third period of the emitted pulse U ₆ , which opens the key device 18.

The signal U ₁₃ from the output of the third trigger 13 through the open key device 18 is fed to the first input of the second trigger 12 and sets it to a single state, starting the formation of signal U _{12 of the} time interval of passage of the ultrasonic signal with a delay of 3 periods of the emitted frequency f _i , i = { 1,2}.

At the same time, the signal U ₁₆ from the output of the counter 16 switches the fourth trigger 17, which with its input signal U ₁₇ prohibits the operation of the counter 16.

The received signals U ₇ (see Fig. 2) are sent to the first comparator 8, which has a threshold of operation U _n > 0 and is always greater than the noise level of the received signal U ₇ and the second comparator 9, which has a threshold of operation U _n = 0, which ensures precise fixation of the beginning of the period of the received sinusoidal signal U ₇ .

Then, from the first comparator 8, the pulses of the signal U ₈ are supplied to the first trigger 10, the signal U _{10 of} which is supplied to the second input of the extraction unit of the third period of the sine wave 11, which passes the signal U ₉ from the second comparator ₉ , corresponding to the third period with a threshold U _n = 0, which ensures high accuracy of delay measurements. This signal is fed to the second input of trigger 12 and returns the trigger to the zero state.

Thus, at the output of the second trigger 12, a pulse U _{12 is formed} , the duration of which is determined only by the wind speed and the speed of ultrasound and does not depend on its frequency and the influence of the environment on it, which ensures high measurement accuracy.

In addition, the signal U ₁₁ from the output of the selection unit of the third period of the sine wave 11 is fed to the second inputs of the first trigger 10, the fourth trigger 17 and the third trigger 13 and restores them to the initial state until the next radiation pulse arrives in the opposite direction.

Next, the pulse U ₁₂ from the second trigger 12 is supplied to the inputs of the synchronization device 23 and the time interval-digit converter 19, in which the duration U _{12 is} converted into a digit, which, through the division unit 20, is fed to the subtraction unit 21, where the difference in the transit time of the ultrasound of the measuring base is obtained L in the figure between the forward and reverse directions. The distance L between the electro-acoustic transducers 1 _I and 2 _I , 1 _II and 2 _II , 1 _III and 2 _III are equal. Moreover, the decline of every second pulse U ₁₂ from the output of the second comparator 12, the synchronization device 23 stops the pulse , and on the corresponding output, the duration of which corresponds to the time for receiving and transmitting back and forth in each measuring base I, II and III, for the time T _ass. necessary for the attenuation of batch processes in devices and for recording information from the output of the subtraction block 21 to the computing device 22.

At the end of time T _back synchronization device 23 generates at its next output a control signal , where i = 1, 2, 3, which connects the next measuring base I, II, and III to switch 5, repeating the previously described process for measuring the difference in ultrasound velocity in the corresponding base.

Since the value of the speed of sound in still air does not change during the measurement, it is excluded by subtraction. The resulting speed difference is determined only by the wind drift of the pulsed ultrasonic signals in the measuring bases I, II and III and does not depend on the values of temperature, relative humidity and atmospheric pressure.

Next, the speed difference obtained in each measuring base I, II and III from the subtraction unit 21 is sequentially supplied to the computing device 22.

Electroacoustic transducers in pairs 1 _I and 2 _I , 1 _II and 2 _II , 1 _III and 2 _III form three measuring bases located at an angle of 120 ° relative to each other and at an angle of (30-60) ° in the vertical plane, which allows for computational device 22 to calculate the horizontal speed and direction of the wind, as well as the vertical component of the wind speed from the measured values of the speed along each of the measuring bases.

Thus, the proposed utility model allows to increase the reliability, manufacturability, reduce cost, weight, dimensions and power consumption by significantly (three times) reducing the number of active devices by changing the functioning algorithm provided by the newly introduced synchronization device and six keys, two in each measuring base, and the logical adder and their interaction with the other nodes of the proposed utility model, thereby improving take-off safety landing aircraft.

INFORMATION SOURCES

1 Russian Federation, patent for invention No. 2030749, IPC: 6 G01P 5/01, 1995

2 Russian Federation, application for invention No. 93049075/28, IPC: 6 G01P 5/01, 1996

3 Russian Federation, patent for invention No. 2093835, IPC: 6 G01P 5/01, 1997

4 Russian Federation, utility model patent No. 44391, IPC: 7 G01P 5/01, 2005

5 Russian Federation, copyright certificate for the invention No. 1081544, IPC: G01P 5/00, G01F 1/66, 1984

6 Russian Federation, utility model patent No. 77975, IPC: 7 G01P 5/01, 2008

7 Russian Federation, utility model patent No. 83620, IPC: 7 G01P 5/01, 06/10/2009.

8 Russian Federation, application for utility model No. 20111115989/28 (023823), decision on the grant of a patent dated 06/09/2011, IPC: 7 G01P 5/01 - prototype.

Claims (1)

An ultrasonic flow velocity meter containing three measuring bases, including two reversible electro-acoustic transducers located at an angle of 120 ° relative to each other and at an angle of 30-60 ° in the vertical plane, as well as a switch to which a transmitter and receiver of pulse signals are connected, three a comparator, four triggers, a third-period sine wave allocation unit, a matching device, a counter, a key device, and a time-to-digital converter in series, a division unit, a subtraction unit and a computing device, while the output of the matching device is connected to the input of the third comparator, the output of which is connected to the first input of the counter, the output of the counter is simultaneously connected to the second input of the key device and to the first input of the fourth trigger, the output of which is connected to the second input of the counter, inputs the first and second comparators are connected to the switch, the output of the first comparator is connected to the first input of the first trigger, the output of the second comparator is connected to the first input of the node I’m the third period of the sine wave, the output of the first trigger is connected to the second input of the selection node of the third period of the sine wave, the output of which is connected to the second inputs of the first, second, third and fourth triggers, and the first input of the third trigger is connected to the switch, the output of the third trigger is connected to the first input of the key a device whose output is connected to the first input of the second trigger, and the output of the second trigger is connected to the time-to-digital converter, characterized in that it is supplemented by a synchronization device and, with a logical adder and six keys, two in each measuring base, while the first input of each key is connected to the output of the corresponding acoustic transducer of its measuring base, the outputs of the keys, the inputs of which are connected to the first electro-acoustic transducers of each measuring base, are simultaneously connected to one input the switch, the outputs of the keys, the inputs of which are connected to the second electro-acoustic transducers of each measuring base, are connected to another input of the switch, the second input the keys of the first measuring base are connected to the first output of the synchronization device, the second inputs of the keys of the second measuring base are connected to the second output of the synchronization device, the second inputs of the keys of the third measuring base are connected to the third output of the synchronization device, the first, second and third inputs of the logical adder are connected to the corresponding outputs of the device synchronization, and its output is simultaneously connected to the switch and the computing device.