CN1791786A - Electronic turbine gas flow meter - Google Patents

Abstract

The invention relates to an electronic turbine gas flowmeter (1), the first basic measurement principle of which is as follows: the kinetic energy of the detected gas flow itself is converted into a rotational movement of a turbine (5), the rotational speed of which is used to determine the gas volume of the gas flow. In order to achieve a high degree of measurement accuracy, in the invention, instead of the gas flow through the turbine blades (6), the gas flow through a special rotor (15) is evaluated and, if necessary, the gas pressures are additionally taken into account by means of a Reynolds linearization, wherein, in addition, the wear of the ball bearings (8) and the fluid pressures acting on the turbine (5) are monitored by means of sensors.

Description

Electronic turbine gas flow meter

technical field

The invention relates to an electronic turbine gas flow meter.

Background technique

Such a turbine gas flow meter with an exchangeable span insert is already known from EP 0 078 334 A1.

The measurement principle of the turbine gas flowmeter is: the kinetic energy of the detected gas flow itself is converted into the rotational motion of the turbine by means of a turbine placed in the flow path of the gas to be detected, wherein, ideally, the rotation speed of the turbine is proportional to Depending on the gas flow rate to be detected or the gas volume to be detected.

Usually, the rotational speed of the turbine is detected by means of corresponding sensor technology. For this purpose, radial sensors are assigned to the turbine in such a way that when the blades of the turbine pass by, pulses are generated which are transmitted to a connected electronic state variable converter. The output shaft of the turbine shaft drives a mechanical gauge. In the front or back of the meter, the already mentioned state quantity converter is generally connected in series, and it performs metering correction on the metering result through the corresponding calibration data. This metrological correction is necessary because the quality of the metrological results is firstly affected by a series of mechanical and hydrodynamic parameters, such as the friction loss of the turbine, which increases with the wear of the turbine's supporting bearings.

In general, if the capacity is low and the gas density is low, the measurement error will be large, because the driving work of the gas on the turbine is relatively small compared with those mechanical influence parameters in this range. The metering result also depends on the geometric size of the meter, especially the pressure of each airflow acting on the impeller, the viscosity coefficient and density of the gas, and the air pressure of the gas.

When calibrating, the main way to consider the influence of these parameters is to obtain a detection error curve and use it to correct each measurement result in the above-mentioned state quantity converter, or to be able to perform such correction. Essentially, the turbine gas flowmeter is operated at only one operating pressure, and therefore also calibrated at this operating pressure, and the correction of the measurement error explained above can then be regarded as sufficiently accurate in conventional characteristic curve correction.

Another major influencing parameter for the measurement results, and thus a possible source of error, is the flow friction of the gas, which has different effects depending on the type of gas flow - laminar or turbulent. Under normal operating conditions of a turbine gas flow meter, the gas flow that occurs is predominantly turbulent, especially in high pressure applications. Ideally, there is a direct proportional relationship between the airflow velocity and the rotational speed of the turbine. The effect of changes in operating pressure can be taken into account by precise interpolation or extrapolation.

For this, however, it is always necessary to measure the operating pressure of the gas to be detected. In a so-called Reynolds-linearization, it is done by means of polynomial coefficients or corresponding correction tables, which take into account the influence of the operating pressure and the above-mentioned Reynolds number, so that the resulting metrological results can be taken into account deviation. This complex approach has been rarely applied so far.

Contents of the invention

The object of the present invention is to create a turbine gas flowmeter with high measurement accuracy and without corresponding complicated subsequent calibration and error correction, which can be used in as wide an application field as possible. The objects of the invention are achieved by the features stated in the main claim. Preferred configurations of the invention are given in the subsidiary claims 2 to 16 .

The turbine gas flowmeter has an electronic meter. Since it is an electronic turbine gas flowmeter, first of all it has no general mechanical problems and corrections, which are essential in mechanical roller meters.

Another major advantage of the gas flow meter of the present invention is that the meter is protected in a sensor housing which is positioned in the same direction as the gas flow and thus significantly reduces the space required. The integrated sensor housing can be subsequently equipped or replaced as required. In this case, within the scope of the invention, the sensor housing can be arranged in front of or behind the turbine of the meter in the flow direction.

Within the scope of the invention, the sensor housing and the meter arranged therein are in data connection with at least one radial sensor element, which differs from the previously described sensor in that the sensor element is not a blade of the turbine, but It is a calculation of the passing of a special rotating body connected to the turbine and rotating with it. The pulses generated by means of the rotating body itself configured for this purpose are detected and processed more clearly and with greater precision than pulses typically generated by passing by turbine blades.

The metering accuracy can be increased by radially further sensors, which are arranged, preferably equidistantly, on an imaginary circular track. By using at least two sensors, a change in the direction of rotation can be detected in a corresponding calculation of the pulse sequence, and possible errors of the other individual sensors can be corrected by means of the resulting interference.

In a preferred configuration, the rotating body is an annular ring rotating together with the turbine, wherein, within the framework of an inductive detector, as in the case here, either solid material (Vollmaterial) or a The passing of the borehole is detected as a signal and processed. With such an eyelet, the rotation of the turbine can be detected more accurately than the movement of the blades.

Such a sensor can be a simple proximity switch, since the rotating body allows a high-precision signal to be generated. Depending on the requirements for detection accuracy and other requirements for auxiliary processing which will be described further on, the measuring device according to the invention can also be equipped with more expensive travel meters.

In a further development of the meter according to the invention, at least one axial sensor is also provided for the rotating body connected to the turbine.

In this configuration, the rotating body additionally has a drilled disk co-rotating with the turbine, so that the passing of the disk generates a density and turbine in an inductive detector without contact. The rotational speed is proportional to the series of pulses.

The measurement results of the axial sensor can be used for interference detection or error correction. If the impeller is equipped with several axial sensors, it is also possible to distinguish the direction of rotation.

In a preferred embodiment, in particular with increased detection accuracy, the meter is equipped with not just one radial or axial sensor of this type, but four sensors arranged equidistantly on the circumference of the ball bearing. By using several sensors, a possible reversal of the direction of rotation of the turbine can be detected, a failure of a sensor can be identified, or the drift of some sensors can be corrected by the resulting interference.

In a further development, the radial and/or axial sensors are produced as analog signal sensors which generate an analog pulse signal as a function of the passing of the rotating body.

Through the calculation and processing of the amplitude or noise of the pulse signal of the radial sensor, the possible imbalance or damage of the ball bearing can be identified according to the wear condition caused by the operation of the ball bearing. Algorithmic processing is also done in the electronic gauge inside the sensor housing of the turbine gas flow meter.

Associated with the processing operation of the analog signal, it is compared with a predetermined range. If a predeterminable threshold value is exceeded or undershot, a warning signal is generated, giving information that the ball bearings of the turbine must be replaced or repaired as soon as possible. The processing of the analog signals of the radial sensors enables detection errors to be detected early and used to prevent possible meter failures in good time. The monitoring of ball bearing wear becomes another measure to improve the detection accuracy of the meter and prevent its failure.

By calculating the analog signal of the sensor, possible changes in the distance between the surface of the sensor and the rotating body and the turbine connected thereto can be detected. In particular, it is particularly advantageous if the rotating body has only one or a few boreholes in the axial and radial directions, since this increases the pulse time of the signal used to calculate the distance between the rotating body and the axial sensor . The distances defined above can thus be detected more precisely than calculations using shorter pulses.

This variation in pitch results from bearing damage, and airflow pressure on the turbine from the airflow. This flow pressure, especially the large load changes that occur when the turbine is started and stopped, can damage the turbine and thus significantly the gauges. Meter manufacturers therefore in principle specify permissible load ranges and permissible load variation ranges.

In a preferred embodiment, the correlation between the pulse signal of the axial sensor and a predetermined threshold value is thus detected and an error and/or warning alarm is generated if an excess occurs. Using the detection results of the axial sensors, it is also possible to determine maintenance intervals, identify trends or issue early warnings.

The arithmetic processing described above allows us to recognize in advance or immediately possible flow meter errors or failures thereof, and in most cases also to determine their causes, in the form of a documentation of possible overloads.

The sensor housing placed inside the gas flow rectifier of the flowmeter is made gas-tight, so that the pressure existing in the sensor housing is separated from the various gas pressures or the operating pressure of the gas to be detected.

The inside of the airtight sensor case is generally set to atmospheric pressure or slightly low pressure (vacuum), and kept constant.

The turbine gas flow meter of the present invention is additionally equipped with a pressure detector which is provided for the pressure chamber of the turbine to measure the gas pressure or operating pressure of the gas to be detected. The gas flow meter is data connected to the electronic meter.

It has been proven here that it is advantageous if the pressure detector arranged in the pressure chamber operates according to the reliable method of differential pressure detection. For this purpose, the pressure detector itself is equipped with a test pressure chamber, which provides a reference value for the differential pressure detection.

In a preferred embodiment, the correction table or the polynomial coefficients for the individual meters can be stored by means of a memory element assigned to the meters, which is likewise arranged in the sensor housing. Through the continuous monitoring of the operating pressure or the gas pressure of the detected gas, and transmitting each operating pressure to the electronic meter, the metering result can be automatically measured in the meter by means of the correction table or polynomial coefficients stored in the storage element. Correction, which takes into account the influence of individual gas densities or individual gas pressures. So far only for a turbine gas flowmeter that has been calibrated for an operating pressure, it can be applied within a predetermined range according to this automatic error correction, with the help of the correction table or polynomial coefficients stored in the above-mentioned storage element. To complete the corresponding correction.

The internal pressure of the sensor housing has nothing to do with various gases, and the combination of the Reynolds number stored in the storage element and the detection of the pressure of each gas makes the use of the turbine gas flowmeter of the present invention not only a range of predetermined operating pressures , but the entire pressure range.

In addition to the automatic consideration of the various gas densities described above, other corrections of the known characteristic curves can be carried out by additionally storing various error curves in the memory element and using them for automatic evaluation of the metering results. fix.

In a further development of the invention, additional pressure sensors are arranged in the flow path of the gas to be detected or in the pressure chamber in which the turbine is arranged, in order to obtain additional relevant measured variables for correcting the metering results.

Further metering-relevant data, such as manufacturer data, test data curves or calibration data, are stored in the memory element of the meter. In particular, the memory element can also be used to display the detection data for a predetermined time period.

In addition, the metering results produced in the electronic meter can be safely protected by means of an emergency power supply.

The fundamental difference between the electronic measuring instrument of the present invention and the traditional measuring instrument is that the measurement result is automatically corrected by means of the data stored in the storage element, such as the operation data of each detection. All measurement results displayed, stored or detected have been corrected for errors within the range of required measurement accuracy.

Description of drawings

The invention is explained in more detail below with the aid of an exemplary embodiment which is shown schematically in the drawing. The picture shows:

Figure 1 is a partial cross-sectional view of an electronic turbine gas flow meter,

Figure 2 is a detailed view of the function of the radial sensor in the turbine gas flowmeter shown in Figure 1, as a top view,

Fig. 3 is another detailed view of the function of the radial sensor in another embodiment of the turbine gas flowmeter shown in Fig. 1, which is a top view,

Fig. 4 is a detailed view of another sensing characteristic of the turbine gas flowmeter shown in Fig. 1, which is a top view of the axial sensor function,

FIG. 5 is a block diagram of an electronic meter in the turbine gas flow meter shown in FIG. 1 .

Detailed ways

The turbine gas flowmeter 1 shown in Fig. 1 mainly includes an airflow channel 2, and the gas to be detected passes through the airflow channel 2 through a gas introduction structure not given further after being introduced, and then flows to an airflow channel 2 which is also not given here. out of the air outlet.

A turbine 5 with turbine blades 6 is accommodated in the gas flow channel 2 . The turbine 5 is mounted on a shaft with two ball bearings 8 . A sensor housing 11 is accommodated in a stationary flow rectifier 10 of the flow meter. The sensor housing 11 is an airtight space in which an electronic meter 3 with a memory element 4 and a processor unit 9 is accommodated.

The sensor housing 11 is equipped with a sensor head 12 with two axially oriented axial sensors 13 and two radially oriented radial sensors 14, which are arranged on an imaginary circumference at In the sensor head 12 which is also airtight. Here, they are inductive proximity switches which are assigned to a rotating body 15 which is on the same shaft 7 as the turbine 5 and rotates with it. For this purpose, the rotary body 15 essentially has a concomitantly rotating disk 16 , the outer circumference of which is bounded by an annular ring 17 , over which the radial sensor 13 and the axial sensor 14 graze and are kept at a distance therefrom.

The sensing technology in the turbine gas flow meter 1 shown in FIG. 1 is given in detail in the detail illustrations given in FIGS. 2 and 3 .

FIG. 2 shows a front-side cross section of sensor head 12 with radially oriented radial sensor 14 .

The sensor head 12 is arranged concentrically with the metal eyelet 17 , which runs together with the rotating body 15 .

Here, in the exemplary embodiment given, the eyelet 17 has two bore holes 18 . The passing of borehole 18 by inductive radial sensor 14 causes a signal interruption 20 whose frequency can be taken as a signal proportional to the rotational speed of turbine 5 .

In a further embodiment shown in FIG. 3 , instead of the corotating eyelet 17 , one or more corotating metal webs 19 can also be assigned to the radial sensor 14 . Their passing by is to pass over the fixed radial sensor 14 . Alternatively, a rotating body made of plastic can be used, which is glued together with metal strips in the region of the rotating eyelet. The metal strip grazes the radial sensor 14 during the rotation of the turbine. In this case, the density of pulses 21 can be calculated instead of signal interruptions 20 .

In addition, axially oriented axial sensors 13 are provided in the sensor head 12, for which they are assigned a disk 16 of a co-rotating rotor 15 with additional bores 18, similar to those shown in FIG. 2, They generate a pulse train proportional to the rotational speed of the turbine 5 .

FIG. 5 shows a block diagram of a meter 3 accommodated in a sensor housing 11 , which has a sensor head 12 positioned upstream.

The sensor head 12 is housed in a pressure-resistant housing and connected to the sensor housing 11 via an airtight glass insulator 22 .

Each sensor 13 or 14 is equipped with a vibrating coil with a proximity switch 23 in the sensor head 12 . The vibrating coil 23 is connected via an amplifier 24 to a signal adapter 25 which is already installed in the subsequent meter housing 11 and is used in particular for analogue preprocessing. The signal processed in this way is then passed on to a processor 9 which, for reasons of interference, is generally double (zwiefach vorhand ist) and is connected to an integrating storage element 4 . The meter 3 is data-connected via a cutting position adapter 26 via corresponding further gas-tight glass insulators 27 to an electronic device, which is additionally arranged outside the turbine gas flowmeter 1, here Not further shown.

The function of the turbine gas flow meter 1 described above will be explained as follows.

The gas to be detected is introduced into a gas flow channel 2 via a gas flow introduction structure, where a turbine 5 on a shaft 7 is arranged. The turbine blades 6 of the turbine 5 are driven to rotate by the kinetic energy of the passing gas. The rotation of the turbine 5 , which is supported on the shaft 7 by two ball bearings 8 , causes the rotating body 15 to pass by the sensors 13 and 14 . The sensor 13 is connected to the electronic meter 3 , which is accommodated in the sensor housing 11 , via corresponding conductive rods. The sensors 13 and 14 emit pulses of a certain density corresponding to the passing of the bore 18 on the rotating body 15 .

In this way, a signal proportional to the gas flow is generated, which can be metered by means of the electronic meter 3 and can be converted to the corresponding detected gas quantity by corresponding conversion.

In addition, a pressure sensor is arranged in the gas flow channel 2, which operates according to the principle of differential pressure detection. As the reference pressure for differential pressure detection, the internal pressure of the pressure detector is used. The sensor housing 11 is hermetically sealed with respect to the other gas flow channels 2 . In the sensor housing 11 there is a vacuum or atmospheric pressure.

The pressure detector placed in the gas flow channel 2 thus gives the respective gas pressure of the gas to be detected. The air pressure can be linked with the correction table and polynomial coefficients stored in the storage element 4 of each flowmeter to eliminate the influence of the gas pressure on the detection result, that is, to determine the real volume of the gas passing through the gas flow channel 2 . In electronic gauges, the so-called Reynolds correction is carried out automatically by means of the correction data respectively assigned to the gauge and stored in the memory element 4, taking into account the air pressure data provided by the pressure detector, and thus automatically corrects the gauge result.

In this way, the above-mentioned turbine gas flowmeter 1 can be calibrated at only one or two operating pressure points.

According to the Reynolds number calibration described, the flowmeter can then be used within a predetermined pressure range, which is determined from the pressure sensors used for detecting the gas pressure, without further calibration or subsequent correction. The field of application of the flowmeter is thus considerably expanded.

Due to the configuration in which the electronic meter is housed in a gas-tight sensor housing 11, it is also possible to realize the suitability of the turbine gas flowmeter 1 for various pressure ranges by completely replacing the sensor housing 11 including the corresponding pressure sensor .

The electronic meter is also connected to a series of other sensors, in particular pressure sensors, by means of which other measured data for error correction are recorded, for example relating to the inertial behavior of the turbine.

The sensor in the sensor head 12 is an analog signal sensor, therefore, conclusions about the operating state of the ball bearing 8 can be obtained by recalculating the pulse sequence of the analog signal, especially the processing of the amplitude of the radial sensor 14 . In this way, a possible imbalance or damage in the ball bearing 8 can be determined from the change in amplitude of the pulse signals supplied by the analog signal sensors 13 , 14 from the passing of the annular ring 17 rotating with an imbalance.

Based on the predetermined threshold value or predetermined bandwidth for the permissible amplitude of the pulses, it can be determined that the ball bearing 8 of the turbine 5 has to be replaced or repaired from that imbalance. In this way, failure of the turbine gas flow meter 1 can be prevented in good time and thus the failure safety factor of the device as a whole is increased.

The calculation of the analog signal, viewed from the axial sensor 13 , gives a measured quantity proportional to the value of the respective fluid pressure acting on the turbine 5 , which is approximately recorded in the memory element 4 . In this way it can be recognized whether the flowmeter 1 is actuated within the allowable range.

In this way, in particular possible malfunctions of the flow meter during start-up and stop-down can be detected. The flow meter can also be replaced in time when necessary.

Above, a turbine gas flowmeter 1 has been described, and its detection accuracy is improved because it is different from a traditional turbine gas flowmeter 1 in that its pulse sequence is not generated by the turbine blade 6 of the turbine 5 passing by. Furthermore, these pulses are transmitted to an electronic meter 3, thus avoiding possible mechanical transmission losses.

The pressure detection is carried out in the gas flow channel 2, in addition a reference pressure is generated by the corresponding pressure sensor itself, and the meter 3 is also provided with a memory element 4, which has the Reynolds number related to the respective flow meter, so that the metering result can be realized Automatically adapt to various pressures of the detected gas itself.

In addition, the turbine gas flow meter 1 of the present invention has the advantage that by monitoring the ball bearings 8 in a relatively strong frictional environment, and the overall fluid pressure acting on the turbine 5 and the flow meter 1, one can protect the Early detection of possible flow meter defects.

Symbol Description

1 Turbine gas flow meter

2 air channels

3 gauges

4 storage elements

5 turbo

6 turbine blades

7 axis

8 ball bearings

9 processors

10 air flow rectifier

11 Sensor housing

12 sensor head

13 Axial sensor

14 radial sensor

15 rotating body

16 platters

17 hole circle

18 holes

19 splices

20 signal interruption

21 pulses

22 Hermetic glass insulators

23 vibrating coil with proximity switch

24 amplifiers

25 signal matcher

26 Cutting position matcher (Schnittstellenanpasung)

27 Other airtight glass insulators

Claims (20)

1. A turbine gas flow meter has a turbine (5), and its turbine blades (6) are placed in the gas flow passage (2) of the gas to be detected, wherein the turbine (5) is placed on a ball bearing supported On the root shaft (7) or wheel shaft, in its stationary air rectifier (10) is arranged a sensor housing (11) with an electronic meter (3), wherein the meter (3) is connected with at least one, Preferably, two radial sensors (14) with fixed positions in the radial direction are connected for data, and the radial sensors (14) are each configured to at least one rotating body (15) that rotates with the turbine (5). The method makes the rotating body (15) respectively generate a pulse sequence proportional to the rotation speed of the turbine (5) when it passes by the axial sensor (14). 2. The electronic turbine gas flowmeter according to claim 1, characterized in that: the rotating body (15) is equipped with radial sensors (14), so that the radial sensors (14) are preferably distributed at equal intervals in an imaginary on the circumference of the circular orbit in . 3. The electronic turbine gas flow meter according to claim 2, characterized in that: the radial sensor (14) is configured as a proximity switch or a trip meter. 4. The electronic turbine gas flowmeter according to any one of claims 1 to 3, characterized in that: the rotating body (15) has an orifice (17) that rotates with the turbine, and the latter has at least one The borehole (18) passing by the radial sensor (14). 5. The electronic turbine gas flowmeter according to any one of the preceding claims, characterized in that: the other sensors (13) configured for the rotating body (15) are oriented along the axial direction, and are arranged in such a way that the rotating body (15) Passing by produces a pulse train proportional to the rotational speed of the turbine (5). 6. The electronic turbine gas flow meter according to claim 5, characterized in that: the rotating body (15) has a circular disk (16) which rotates with the turbine (5), and has at least A borehole (18) passes by the axial sensor (13) for a specific purpose. 7. The electronic turbine gas flowmeter according to one of the preceding claims, characterized in that: the radial and/or axial sensors (13, 14) configured for the rotating body (15) are manufactured as analog signal sensors and generate An analog pulse signal whose amplitude and/or noise is fed to the meter for further processing, preferentially to identify possible imbalances or damage to the ball bearings (8) and/or to the turbine (5) Each fluid pressure. 8. The electronic turbine gas flowmeter as claimed in claim 7, characterized in that: the processing operation of the analog pulse signal is compared with a preset threshold value, and a warning signal is displayed when the threshold value is exceeded. 9. The electronic turbine gas flowmeter as recited in one of the preceding claims, characterized in that the sensor housing (11) is designed gas-tight. 10. The electronic turbine gas flow meter according to claim 9, characterized in that: the sensor casing (11) has an airtight glass insulator (22) to connect to the power supply, and also has other sensors and/or data processing instruments. 11. Electronic turbine gas flowmeter according to one of the preceding claims, characterized in that atmospheric pressure or a vacuum with a defined negative pressure is adjusted in the sensor housing (11). 12. The electronic turbine gas flowmeter according to one of the preceding claims, characterized in that a pressure sensor is provided for the pressure chamber receiving the turbine (5) to detect the pressure of each gas. 13. The electronic turbine gas flow meter according to claim 12, characterized in that the pressure sensor for air pressure detection detects the pressure difference, wherein the constant pressure inside the sensor housing (11) is used as the reference pressure for detection. 14. The electronic turbine gas flowmeter according to claim 12, characterized in that: a pressure sensor is provided for the pressure chamber receiving the turbine (5) to detect the pressure of each gas, wherein the pressure sensor is equipped with a detection pressure chamber, It maintains a constant pressure, which is used as a reference pressure by the pressure detector during differential pressure detection. 15. The electronic turbine gas flow meter according to one of the preceding claims, characterized in that the electronic meter (3) is equipped with a memory element (4), wherein the memory element (4) stores the The correction tables or polynomial coefficients respectively configured by the instrument, and with the help of these data, automatically perform Reynolds corrections for each measurement result according to each detected air pressure value. 16. The electronic turbine gas flowmeter according to claim 15, characterized in that: with the help of other calibration data stored in the storage element (4), preferably the detection error curve, the characteristic curve is calibrated and/or Make other corrections to the measurement results as required. 17. The electronic turbine gas flowmeter according to any one of the preceding claims, characterized in that: the gas flow passage (2) of the gas to be detected is equipped with other pressure sensors to detect other parameters, especially possible The occlusion pressure of these pressure sensors is connected with the data between the gauge (3) arranged in the sensor housing (11). 18. The electronic turbine gas flowmeter according to one of the preceding claims, characterized in that: in the storage element (4) of the meter (3), additional data about the turbine gas flowmeter (1) are stored, In particular manufacturer data, test values, measured value curves and/or calibration data. 19. The electronic turbine gas flow meter according to any one of the preceding claims, characterized in that: the meter (3) arranged in the sensor housing (11) and the relevant emergency power supply, especially one arranged in the sensor housing (11) Connect to a battery other than the power supply. 20. The electronic turbine gas flow meter according to one of the preceding claims, characterized in that the meter (3) is equipped with at least one processing unit (9), wherein, by means of sensors (13, 14 connected by phases ), and taking into account the correction data and calibration data stored in the storage element (4), each measurement result is automatically corrected, so that the measurement state quantity stored in the electronic meter (3) has been Errors are eliminated. 21. The electronic turbine gas flow meter according to one of the preceding claims, characterized in that the meter (3) is equipped with at least one further processing unit and/or constitutes an electronic device for subsequent processing in an interference manner.

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