JP2021032637A - Simulator for coriolis flowmeters and coriolis flowmeter having simulator within - Google Patents

Abstract

To provide a simulator for coriolis flowmeters which generates a simulated phase signal of high reproducibility and outputting it to a conversion unit and performing a calibration process without actually flowing a fluid to a detection unit.SOLUTION: The simulator comprises: a sine wave generation unit 2 for generating a plurality of sine wave signals of a fluid-simulating frequency; an A/D conversion unit 3 for converting the signal wave signal into digital data; a phase shift unit 4 for adding a prescribed phase difference that simulates the prescribed flowrate of the fluid, to the digital data; and a simulated signal output unit 5 for converting the digital data and the digital data having had the prescribed phase difference added thereto into two simulated phase signals that are analog signals and outputting the resultant signals. Due to the fact that two simulated phase signals having the prescribed phase difference of high reproducibility are outputted to the conversion unit of the coriolis flowmeter and a calibration process is performed, a random variation per coriolis flowmeter decreases.SELECTED DRAWING: Figure 2

Description

The present invention relates to a simulator for a Koriori flow meter that simulates a phase signal input from a detection unit to a conversion unit of the Koriori flow meter, and a Koriori flow meter having the simulator built-in.

The Coriolis flow meter measures the Coriolis force to obtain the mass flow rate of a fluid because the Coriolis force generated when a flowing fluid is vibrated is proportional to the product of the mass and velocity of the fluid.

The Coriolis flow meter includes a detection unit that detects the Coriolis force and a conversion unit that converts the detected Coriolis force into a mass flow rate. The detection unit vibrates a tube body such as a U-shape through which the fluid to be measured flows, measures the displacement at two different points upstream and downstream of the tube body, and measures the temperature in the vicinity of the tube body with a temperature sensor. Then, in the conversion unit connected to the detection unit, the flow rate and density of the fluid to be measured are calculated based on the phase difference, frequency, and temperature of the measured displacements of the two points.

As described in Patent Document 1, the Koriori flow meter stores the calibration values obtained by the measurement by the actual flow under the test conditions of a factory or the like, and the above-mentioned flow rate using these calibration values is stored. , It is possible to measure the density accurately.

Special Publication No. 2007-521470

The pre-shipment calibration process of the Coriolis flow meter is performed by flowing a fluid of a predetermined density into the tube at a predetermined flow rate value set by a test device. At this time, the detection unit measures the displacements of two different points in the upstream and downstream directions, and the conversion unit extracts the phase difference between the two displacements and calculates the flow rate. Then, the measured value of the flow rate calculated by the conversion unit is calibrated so as to match the predetermined flow rate value set by the test equipment.

However, in the above calibration process, it is necessary to actually flow the fluid through the tube, and high accuracy is required for the temperature and flow rate uniformity and temporal stability of the flowing fluid, so the test equipment is high-performance and large. There is a problem that the scale becomes large and the calibration work is complicated and time-consuming.

In addition, since the phase difference output by the detection unit of the Koriori flow meter is as small as 0.1 to several mrad, the environment for performing calibration processing such as temperature must be strictly controlled and stable. There is also a problem that the place where the calibration process can be performed is limited and it cannot be performed efficiently.

An object of the present invention is to solve the above-mentioned problems, generate a simulated phase signal of a fluid set to a predetermined flow rate, output it to a conversion unit of the Koriori flow meter, and perform reproducible calibration with less variation for each Koriori flow meter. It is an object of the present invention to provide a simulator for a Koriori flow meter capable of performing processing and a Koriori flow meter having a built-in simulator.

The simulator for a Koriori flow meter according to the present invention for achieving the above object can be connected to the conversion part of the Koriori flow meter including a detection part attached to a tube body through which the fluid to be measured flows and a conversion part. A pair of Koriori flow meter simulators including a simulated signal output unit that outputs a simulated phase signal at the time of calibration, wherein the conversion unit is arranged upstream and downstream of the tube body that vibrates by the drive coil of the detection unit. It is characterized by having a coil vibration receiving circuit unit for connecting the vibration detecting coil of the above, and connecting the simulated signal output unit to the coil vibration receiving circuit unit instead of connecting the vibration detecting coil.

In addition, the Corioli flowmeter with a built-in simulator according to the present invention for achieving the above object has a detection unit attached to a pipe body through which the fluid to be measured flows, and the pipe body vibrating by the drive coil of the detection unit. A Corioli flowmeter equipped with a conversion unit having a coil input end for connecting a pair of vibration detection coils arranged upstream and downstream, and a built-in Corioli flowmeter simulator for calculating the flow rate and density of the fluid flowing through the tube. In, a Corioli flow meter simulator is arranged between the pair of vibration detection coils and the input end portion, and the Corioli flow meter simulator is used from one of the pair of vibration detection coils. The A / D converter that converts the sine wave signal of the above to the sine wave digital data and the sine wave digital data are input, and the phase shift sine wave digital data whose phase is shifted based on the set predetermined phase angle is output. A phase shift unit, a simulated signal output unit that inputs the sine wave digital data and the phase shift sine wave digital data, converts them into two sine wave signals, and outputs the simulated phase signal, and inputs the simulated phase signal. Alternatively, the input of the vibration detection coil can be switched, and one of the inputs is provided with a switching unit that outputs the input to the input end portion.

According to the Koriori flow meter simulator according to the present invention and the Koriori flow meter having the simulator built-in, the simulated phase signal of the fluid set to a predetermined flow rate is transmitted to the detection unit of the Koriori flow meter without actually flowing the fluid. It can output stably to the conversion part of the flow meter with high reproducibility.

Further, by using the simulated phase signal for the calibration process of the conversion unit, it is possible to correct the calibration variation for each Coriolis flowmeter. Further, it is possible to efficiently check the operation of the conversion unit, confirm the accuracy, and perform the calibration process without actually flowing the fluid through the detection unit of the Coriolis flow meter.

It is a block block diagram of a Coriolis flow meter. It is a block block diagram of the simulator for Coriolis flow meter of Example 1 connected with the conversion part of the Coriolis flow meter. It is a circuit diagram of a temperature signal output circuit simulating a resistance temperature detector. It is a block diagram explaining the process of generating a phase shift sinusoidal digital data in detail. It is a block block diagram of the simulator for Coriolis flow meter of Example 2 connected to the conversion part and the detection part of a Coriolis flow meter. It is a block block diagram of the simulator for Coriolis flow meter of Example 3 connected to the conversion part and the detection part of a Coriolis flow meter. It is a block block diagram of the Coriolis flowmeter which built in the simulator of an Example.

The present invention will be described in detail based on the reference example shown in FIG. 1 and the examples shown in FIGS. 2 to 7.
FIG. 1 is a block configuration diagram of a Coriolis flowmeter that can be connected to the Coriolis flowmeter simulator according to the present invention. The Coriolis flow meter has a detection unit K that generates a Coriolis force in the flowing fluid to measure the displacement, and a conversion unit H that calculates the displacement detected by the detection unit K to calculate the corresponding mass flow rate of the fluid. It is composed of and.

The detection unit K is attached to, for example, a symmetrical U-shaped tube P through which the fluid to be measured flows, and the drive coil L1 arranged at the symmetrical center position of the tube P and the tube P. The upstream vibration detection coil L2 arranged upstream from the center position of the pipe body P, the downstream vibration detection coil L3 arranged downstream from the center position of the pipe body P, and the temperature sensor TD placed near the pipe body P. It is composed of and.

The conversion unit H is a coil vibration connected to a drive circuit H1 connected to the drive coil L1 of the detection unit K and upstream and downstream vibration detection coils L2 and L3 which are a pair of vibration detection coils of the detection unit K. The receiving circuit unit H2, the temperature signal receiving unit H3 connected to the temperature sensor TD of the detection unit K, and the phase difference / frequency calculation unit H4 connected to the coil vibration receiving circuit unit H2 and the temperature signal receiving unit H3. It is composed of a flow rate / density calculation unit H5 connected to the phase difference / frequency calculation unit H4 and an output unit H6 connected to the flow rate / density calculation unit H5.

The drive circuit H1 drives the drive coil L1 with AC power having a predetermined frequency, which is the natural frequency of the tube body P. The coil vibration receiving circuit unit H2 is provided with an upstream coil signal receiving circuit H2a and a downstream coil signal receiving circuit H2b in parallel, and the input side of the upstream coil signal receiving circuit H2a is a detection unit K. The upstream side vibration detection coil L2 and the input side of the downstream side coil signal receiving circuit H2b are connected to the downstream side vibration detection coil L3 of the detection unit K, respectively.

Further, the output sides of the upstream coil signal receiving circuit H2a and the downstream coil signal receiving circuit H2b are connected to the phase difference / frequency calculation unit H4 in parallel, respectively. The upstream coil signal receiving circuit H2a and the downstream coil signal receiving circuit H2b amplify the coil signal due to the vibration of the tube body P detected by the upstream vibration detecting coil L2 and the downstream vibration detecting coil L3, respectively, and the phase difference / Output to the frequency calculation unit H4.

The temperature signal receiving unit H3 receives the temperature signal measured by the temperature sensor TD, calculates the temperature value, and outputs the temperature value to the phase difference / frequency calculation unit H4. The phase difference / frequency calculation unit H4 calculates the phase difference between the two signals and the frequency of the coil signal from the input upstream coil signal and downstream coil signal, and corrects with the temperature value input from the temperature signal receiving unit H3. After the addition, the phase difference and frequency information is output to the flow rate / density calculation unit H5.

The flow rate / density calculation unit H5 calculates the fluid flow rate and density information from the phase difference / frequency information input from the phase difference / frequency calculation unit H4, and outputs the information to the output unit H6. The output unit H6 outputs the input fluid flow rate and density information to a connected device such as a touch panel, a display, a printer, a process control device, an external personal computer or a server.

The conversion unit H of the Koriori flow meter is configured to be separable by disconnecting the connection with the detection unit K, and is configured to be separable from the drive coil L1 and the drive circuit H1, the upstream vibration detection coil L2 and the upstream coil signal reception circuit H2a, and the downstream. The side vibration detection coil L3 and the downstream coil signal receiving circuit H2b, the temperature sensor TD and the temperature signal receiving unit H3 can be individually and arbitrarily separated from each other.

FIG. 2 is a block configuration diagram of the Coriolis flow meter simulator 1 of the first embodiment connected to the conversion unit H. At the input ends of the upstream coil signal receiving circuit H2a and the downstream coil signal receiving circuit H2b of the coil vibration receiving circuit unit H2 of the converting unit H, the upstream side vibration detecting coil L2 and the downstream side vibration detecting coil L3 of the detecting unit K are located. Instead, a simulated signal output unit that outputs a simulated calibration signal of the coilor flow meter simulator 1 of the first embodiment is connected.

The Koriori flow meter simulator 1 includes a sine wave transmission unit 2, an A / D conversion unit 3 connected to the sine wave signal transmission unit 2, and a phase shift unit 4 connected to the A / D conversion unit 3. , A / D conversion unit 3 and a simulated signal output unit 5 connected to the phase shift unit 4.

The sine wave transmitting unit 2 is composed of a frequency setting unit 2a and a sine wave generating unit 2b, and is a sine wave simulating a sine wave signal to be detected by the upstream vibration detection coil L2 and the downstream vibration detection coil L3 of the detection unit K. Output a signal. Although not shown, the frequency setting unit 2a includes an input unit such as an input terminal provided with a touch panel, a key switch, or a communication means, and an arithmetic processing unit for calculating waveform period / amplitude data corresponding to the set frequency. There is.

A frequency corresponding to the natural frequency is set in the input unit, and the arithmetic processing unit can calculate waveform period / amplitude data corresponding to the set frequency of the tube P based on the set frequency. It is also possible to acquire the natural frequency of the tube P from the detection unit K or the conversion unit H by the communication means of the input unit and use it for calculating the waveform period / amplitude data in the arithmetic processing unit.

The waveform period / amplitude data of the set frequency calculated by the frequency setting unit 2a is transmitted to the sine wave generation unit 2b to generate a sine wave signal which is an analog signal having a frequency corresponding to the natural frequency of the tube P. , Is output to the A / D conversion unit 3. This sine wave signal is the upstream vibration detection coil L2 and the downstream vibration detection coil when the tube P is vibrated at the natural frequency by the drive coil L1 when the tube P is filled with fluid. It is a signal simulating the frequency of the sinusoidal signal to be detected by L3. The A / D conversion unit 3 samples the sine wave signal, converts it into sine wave digital data, and outputs it in parallel to the phase shift unit 4 and the simulated signal output unit 5.

The phase shift unit 4 is composed of a phase angle setting unit 4a for setting a phase angle corresponding to a phase difference, and a phase shift signal generation unit 4b connected to the A / D conversion unit 3. Then, the phase shift unit 4 transmits the phase difference simulating the phase difference between the two sinusoidal signals to be detected by the upstream vibration detection coil L2 and the downstream vibration detection coil L3 of the detection unit K from the A / D conversion unit 3. It has a function to shift the phase by adding it to the input sinusoidal digital data.

The phase angle setting unit 4a includes, for example, an input unit such as a touch panel, a key switch, or an input terminal provided with a communication means, and an arithmetic processing unit for calculating the phase angle to be set. The input unit and the arithmetic processing unit of the frequency setting unit 2a of the sine wave transmitting unit 2 may be shared as the input unit and the arithmetic processing unit of the phase angle setting unit 4a, and the Koriori flow meter simulator 1 is downsized. be able to.

In the phase angle setting unit 4a configured in this way, the arithmetic processing unit sets an appropriate phase angle to be added to the sinusoidal digital data based on the instruction information input from the input unit. With this phase angle, when the fluid is flowing in the tubular body P at a predetermined flow rate and a predetermined temperature, when the tubular body P is vibrated at a natural frequency by the drive coil L1, the upstream side vibration detection coil L2 and the downstream side vibration detection are performed. It corresponds to the phase difference simulating the phase difference between the two sinusoidal signals to be detected by the coil L3.

The phase angle setting unit 4a transmits the calculated phase angle value to the phase shift signal generation unit 4b. The phase shift signal generation unit 4b adds a phase difference corresponding to the phase angle transmitted from the phase angle setting unit 4a to the sinusoidal digital data input from the A / D conversion unit 3, and the phase shift sinusoidal digital It is output as data to the simulated signal output unit 5.

The simulated signal output unit 5 is a D / A conversion unit having two channels of input / output terminals, and the output of the phase shift signal generation unit 4b of the phase shift unit 4 is connected to the input terminal of the channel CH1. The sine wave digital data output from the A / D conversion unit 3 is input to the input terminal IN of the channel CH1 as phase shift sine wave digital data via the phase shift signal generation unit 4b.

Further, the output of the A / D conversion unit 3 is directly connected to the input terminal of the channel CH2, and the sine wave digital data output from the A / D conversion unit 3 is directly input to the input terminal IN of the channel CH2. ..

The upstream coil signal receiving circuit H2a and the downstream coil signal receiving circuit H2b of the coil vibration receiving circuit unit H2 of the conversion unit H are connected to the output terminal OUT of the channel CH1 of the simulated signal output unit 5 and the output terminal OUT of the channel CH2, respectively. It is connected. The simulated signal output unit 5 uses the phase shift sine wave digital data input from the phase shift signal generation unit 4b, which is a digital signal, and the sine wave digital data input from the A / D conversion unit 3 as analog signals. It is converted into a shift sine wave signal and a sine wave signal, and output in synchronization with the upstream coil signal receiving circuit H2a and the downstream coil signal receiving circuit H2b.

These phase-shifted sine wave signals and sine wave signals are upstream when the pipe body P is vibrated at a natural frequency by the drive coil L1 when the fluid is flowing in the pipe body P at a predetermined flow rate and a predetermined temperature. These are two simulated phase signals simulating a sine wave signal having two phase differences to be detected by the side vibration detection coil L2 and the downstream vibration detection coil L3.

In the above embodiment, the sine wave digital data generation unit is composed of the sine wave transmission unit 2 and the A / D conversion unit 3, but the configuration of the sine wave digital data generation unit is not necessarily limited to this. is not it. The sine wave digital data generation unit is not provided with the A / D conversion unit 3, and instead of the sine wave generation unit 2b of the sine wave transmission unit 2, the sine wave digital is generated from the waveform period / amplitude data. A data generation unit 2b'can also be provided. In this case, the waveform period / amplitude data set by the frequency setting unit 2a of the sine wave transmitting unit 2 is directly converted into sine wave digital data without using an analog signal.

Further, a temperature signal output terminal of the temperature signal output means THM is connected to the temperature sensor input end of the temperature signal receiving unit H3 of the conversion unit H. The temperature signal output means THM includes a temperature sensor TD similar to the detection unit K, a thermometer having a temperature signal output terminal, a resistance temperature detector RTD, an appropriate temperature signal output means such as a thermocouple, and a pseudo temperature. A temperature signal output circuit that generates a signal can also be used. Further, the temperature signal output means THM may be provided inside the Coriolis flow meter simulator 1. Since the other configurations of the conversion unit H shown in FIG. 2 are the same as those shown in FIG. 1, they are not shown in FIG.

FIG. 3 is a circuit diagram of a temperature signal output circuit simulating a resistance temperature detector used as a temperature signal output means THM. N circuits in which resistors R1 to RN corresponding to resistance values of resistance temperature detectors at predetermined temperatures T1 to TN are connected to resistance changeover switches SWR1 to SWRN are connected in parallel. By turning on any one of the resistance changeover switches SWR1 to SWRN, a temperature signal corresponding to any one of the predetermined temperatures T1 to TN can be generated.

By using a temperature signal output circuit as the temperature signal output means THM, calibration at a predetermined temperature without changing the temperature of the entire Koriori flow meter calibration system including the Koriori flow meter simulator 1 and the conversion unit H to a predetermined temperature. Can be simulated, and the effect of temperature changes on calibration can be easily grasped.

When the calibration process of the conversion unit H is performed by the Koriori flow meter simulator 1 of the first embodiment connected to the conversion unit H in this way, the frequency setting unit 2a of the sine wave transmission unit 2 first transmits. Set the sine wave waveform to be made.

Assuming that the tube P is filled with fluid, for example, the frequency of the sine wave can be increased by directly inputting a predetermined frequency value corresponding to the natural frequency of the tube P to the input section of the frequency setting unit 2a. Set. In the arithmetic processing unit of the frequency setting unit 2a, the waveform period / amplitude data corresponding to the set frequency is calculated and transmitted from the frequency setting unit 2a to the sine wave generation unit 2b. The sine wave generation unit 2b generates a sine wave signal, which is an analog signal of a predetermined frequency, based on the waveform period / amplitude data, and outputs the sine wave signal to the A / D conversion unit 3.

When the sine wave signal of a predetermined frequency is input to the A / D converter 3, the waveform is sampled, and the sine wave signal of the predetermined frequency becomes sine wave digital data which is a digital signal consisting of a data group such as 16 bits. Will be converted. As a method for converting a sine wave signal into a digital signal, an existing appropriate conversion method can be adopted. This sine wave digital data is output from the A / D conversion unit 3 to the phase shift signal generation unit 4b of the phase shift unit 4, and is also output to the channel CH2 input terminal of the simulated signal output unit 5.

In the phase angle setting unit 4a of the phase shift unit 4, the phase angle to be added to the sinusoidal digital data is set in advance with a required resolution. First, in the input unit of the phase angle setting unit 4a, in order to set the phase angle, a predetermined flow rate and a predetermined temperature of the fluid to be flowed through the tube body P of the detection unit K when calibration is assumed are input as instruction information. To do. Subsequently, the arithmetic processing unit assumes that the fluid flows at a predetermined flow rate and a predetermined temperature based on the instruction information, and at that time, the measurement should be performed by each of the upstream vibration detection coil L2 and the downstream vibration detection coil L3. The phase angle corresponding to the phase difference between the two sinusoidal signals is calculated. Then, the calculated phase angle value is previously transmitted from the phase angle setting unit 4a to the phase shift signal generation unit 4b.

When the sine wave digital data is input to the phase shift signal generation unit 4b in such a state, the phase of the sine wave digital data is shifted by the required resolution by the preset phase angle value, and the phase is shifted. Shift sine wave digital data is generated.

FIG. 4 is a block diagram illustrating in detail the process of generating this phase-shifted sinusoidal digital data. In the frequency setting unit 2a of the sine wave transmission unit 2 in advance, waveform period / amplitude data is set for a predetermined frequency. For this waveform period / amplitude data, for example, a 16-bit data group or the like representing the phase and amplitude with respect to the time of one cycle of a predetermined frequency can be used.

The sine wave signal, which is an analog signal of a predetermined frequency transmitted from the sine wave generation unit 2b of the sine wave transmission unit 2 based on the waveform period / amplitude data, has an amplitude value for each predetermined sampling time by the A / D conversion unit 3. Is sampled and converted into sinusoidal waveform data, which is, for example, a 16-bit digital data group of amplitude values.

Further, the phase data of the sine wave signal is, for example, 16-bit data, and is extracted from the sine wave signal by a circuit such as a comparator provided in the A / D conversion unit 3. By combining these sine wave waveform data and phase data, sine wave digital data obtained by digitizing a sine wave signal which is an analog signal is generated. In the case where the sine wave digital data generation unit is not provided with the A / D conversion unit 3 and the sine wave digital data generation unit 2b'is provided instead of the sine wave generation unit 2b of the sine wave transmission unit 2. Generates sine wave digital data consisting of sine wave waveform data and phase data from waveform period / amplitude data without using a sine wave signal.

One of the sinusoidal digital data generated in this way is directly output to the simulated signal output unit 5 without going through the phase shift unit 4, and the other is output to the simulated signal output unit 5 via the phase shift unit 4. To. When the sine wave digital data is input to the phase shift signal generation unit 4b of the phase shift unit 4, the shift is, for example, 16-bit digital data representing the phase angle value calculated and transmitted in advance by the phase angle setting unit 4a. The phase angle is added by bit calculation to the phase data of the sinusoidal digital data which is 16-bit data.

In this way, without adding arithmetic processing to the sinusoidal waveform data of the sinusoidal digital data, only the shift phase angle is added to the phase data by bit arithmetic, and the phase is accurately shifted by the set phase angle value. It is possible to generate phase-shifted sinusoidal digital data.

Then, the input terminal IN of the channel CH1 of the simulated signal output unit 5 shown in FIG. 2 has the above-mentioned other phase shift sine wave digital data, and the input terminal IN of the channel CH2 has the above-mentioned one sine wave digital data. Are entered respectively. In the simulated signal output unit 5, the phase shift sine wave digital data and the sine wave digital data are converted into the phase shift sine wave signal and the sine wave signal, which are analog signals, respectively.

The phase-shifted sine wave signal converted into an analog signal is output from the output terminal OUT of the channel CH1 to the coil signal receiving circuit H2a on the upstream side of the coil vibration receiving circuit unit H2 of the conversion unit H. Further, in synchronization with this, the sine wave signal is output from the output terminal OUT of the channel CH2 to the coil signal receiving circuit H2b on the downstream side of the coil vibration receiving circuit unit H2 of the conversion unit H.

In this way, when the pipe body P is vibrated at the natural frequency by the drive coil L1 in a state where the fluid is flowing through the pipe body P of the detection unit K at a predetermined flow rate and a predetermined temperature, it is upstream of the detection unit K. The phase shift sine wave signal simulating the signal to be detected by the side vibration detection coil L2 and the sine wave signal simulating the signal to be detected by the downstream vibration detection coil L3 are synchronized to have a predetermined phase difference. It can be output as a simulated phase signal from the Koriori flow meter simulator 1 to the conversion unit H.

Since the simulated phase signal is generated in the simulator 1 for the Koriori flow meter, it is affected by the instability of the flow rate of the fluid flowing through the tube P of the detection unit K and the instability of the environment such as the temperature of the detection unit K. Instead, a stable and highly reproducible signal can always be supplied to the conversion unit H for calibration processing. Further, the phase difference between the phase-shifted sine wave signal and the sine wave signal is added by bit calculation to the sine wave digital data obtained by digitally converting the sine wave signal into, for example, a 16-bit waveform data group. It is not easily affected by noise and is highly accurate and reproducible.

The phase shift sine wave signal and the sine wave signal input to the upstream coil signal receiving circuit H2a and the downstream coil signal receiving circuit H2b of the coil vibration receiving circuit unit H2 of the conversion unit H are amplified so as to be able to perform arithmetic processing. Is output to the phase difference / frequency calculation unit H4. On the other hand, a temperature signal is input from the temperature signal output means THM to the temperature signal receiving unit H3 of the conversion unit H, a temperature value is calculated from the temperature signal, and the temperature value is output to the phase difference / frequency calculation unit H4.

In the phase difference / frequency calculation unit H4, the phase difference of the phase shift sine wave signal and the sine wave signal and the phase shift sine wave signal or the sine wave are based on the input phase shift sine wave signal, sine wave signal, and temperature value data. The frequency of the wave signal is calculated. The calculated phase difference and frequency are input to the flow rate / density calculation unit H5, and the phase difference is the flow rate of the fluid corresponding to the phase difference of the simulated phase signal from the simulator 1 for the Koriori flow meter, and the frequency is the Koriori flow rate. The density of the fluid corresponding to the frequency of the simulated phase signal from the instrument simulator 1 is calculated.

The calculated flow rate and density of the fluid are output to the output unit H6, displayed on a touch panel, a display, or the like, and output to the outside as process variables of a device or the like connected to the tube body P, for example.

The operator performing the calibration process determines that the fluid flow rate and density displayed as the simulated measurement result are the fluids assumed when the phase-shifted sine wave signal and the sine wave signal are generated in the simulator 1 for the Koriori flow meter. The conversion unit H is calibrated so as to match the flow rate and the predetermined density.

In the specific flow rate calibration, the flow rate of the fluid displayed as a simulated measurement result matches the predetermined flow rate of the fluid assumed in advance by the phase angle setting unit 4a of the phase shift unit 4 of the simulator 1 for the Koriori flow meter. As described above, the drive circuit H1 of the conversion unit H, the coil vibration receiving circuit unit H2, the phase difference / frequency calculation unit H4, and the like are calibrated. Further, in the specific density calibration, the density of the fluid displayed as a simulated measurement result becomes a predetermined density of the fluid assumed in advance by the frequency setting unit 2a of the sine wave transmitting unit 2 of the simulator 1 for the Koriori flow meter. The calibration of each part of the conversion unit H is performed in the same manner so as to match.

By connecting an operation control device such as a personal computer to the Koriori flow meter simulator 1 and the conversion unit H, the Koriori flow meter simulator 1 sets the predetermined density and the predetermined flow rate of the fluid, and the conversion unit H sets the density and the flow rate. It is also possible to automatically perform calibration work such as monitoring of simulated measured values.

As described above, the simulated phase shift sine wave signal and the sine wave signal for calibration supplied from the simulator 1 for the Koriori flow meter to the conversion unit H actually flow a fluid through the tube body P of the detection unit K. Since it is superior in reproducibility and stability to the obtained signal, the conversion unit H can be calibrated with high reproducibility and stability. In particular, when calibration processing of the conversion unit H of a plurality of Corioli flow meters is performed by the simulator 1 for a Corioli flow meter having a simulated phase signal output generated digitally, a correction coefficient for correcting the calibration variation for each conversion unit H. Can be determined, and the compatibility of the conversion unit H can be guaranteed. Further, since it is not necessary to actually flow the fluid through the pipe body P during the calibration process, the equipment required for the calibration becomes inexpensive and the calibration work itself becomes simple.

FIG. 5 is a block configuration diagram of the Coriolis flowmeter simulator 1'of Example 2 connected to the conversion unit H and the detection unit K of the Coriolis flowmeter. The drive coil L1 of the detection unit K is connected to the drive circuit H1 of the conversion unit H. The Coriolis flow meter simulator 1'is not provided with a sine wave transmitting unit 2, and a vibration detection coil L3 on the downstream side of the detection unit K is connected to the input side of the A / D conversion unit 3. Since other configurations are the same as those in the first embodiment, the description thereof will be omitted. In FIG. 5, the downstream vibration detection coil L3 of the detection unit K is connected to the input side of the A / D conversion unit 3, but the upstream vibration detection coil L2 is connected to the input side of the A / D conversion unit 3. It can also be a connected configuration.

In the Koriori flow meter simulator 1'configured in this way, first, the drive coil L1 of the detection unit K is driven by the drive circuit H1 of the conversion unit H with AC power of a predetermined frequency matching the natural frequency of the tube body P. Will be done. In that case, it is necessary that the tube body P of the detection unit K is filled with a liquid or gas fluid, but it is not necessary to flow the fluid. The tube body P is vibrated by the drive coil L1 and undergoes minute vibration with a sine wave having a natural frequency including the mass of the fluid. The sine wave vibration of the tube body P is detected by the downstream vibration detection coil L3, and is input as a sine wave signal to the A / D conversion unit 3 of the Koriori flow meter simulator 1'. That is, in the simulator 1 for the Koriori flow meter of the first embodiment, a sine wave signal equivalent to the sine wave signal generated by the sine wave transmitting unit 2 is used, and in the simulator 1'for the Koriori flow meter, the tube P of the detection unit K is unique. It is generated by actually vibrating at a frequency. The operation after the sine wave signal is input to the A / D conversion unit 3 is the same as that in the first embodiment, and thus the description thereof will be omitted.

The Coriolis flowmeter simulator 1'configured in this way is smaller and cheaper because it does not require a sine wave transmitter. Further, it is not necessary to calculate the natural frequency of the pipe body P in the Coriolis flow meter simulator 1'. Further, since the AC power for actually exciting the tube P to obtain the sine wave signal is given by the drive circuit H1 of the conversion unit H, the sine wave signal is input to the A / D conversion unit 3. There is also an advantage as a checker that the operation of the drive circuit H1 can be checked.

FIG. 6 is a block configuration diagram of the Coriolis flowmeter simulator 1 ”of Example 3 connected to the conversion unit H and the detection unit K of the Coriolis flowmeter. In the Coriolis flowmeter simulator 1'of Example 2, the outside is shown. In contrast to the temperature signal output means THM provided in the Coriolis flow meter simulator 1 ”, the temperature signal output means THM is provided inside, and the temperature of the detection unit K is used as the temperature signal output means THM. The same temperature sensor TD as the sensor TD is used. Since other configurations are the same as those in the second embodiment, the description thereof will be omitted.

In the Corioli flow meter simulator 1 of the third embodiment configured in this way, the sine wave signal is transmitted to the A / D conversion unit 3 from the vibration of the tube body P of the detection unit K by the drive circuit H1 of the conversion unit H. The operation until the input is the same as that of the second embodiment, and the operation after the sine wave signal is input to the A / D conversion unit 3 is the same as that of the first embodiment. Therefore, the description thereof will be omitted.

In the Koriori flow meter simulator 1 ”configured in this way, the same temperature sensor TD as the temperature sensor TD of the detection unit K is used as the temperature signal output means THM. The temperature of the conversion unit 3 from the temperature signal output means THM. By outputting a calibration temperature signal of a predetermined temperature to the signal receiving unit H3, the operation of the temperature signal receiving unit H3 can be checked and calibrated. The temperature signal receiving unit H3 can actually check the operation of the temperature signal receiving unit H3 from the input calibration temperature signal. The temperature value is calculated and output to the phase difference / frequency calculation unit H4. This temperature value is output to the output unit H6 via the flow rate / density calculation unit H5 together with the calculated flow rate and density of the fluid. The operator can calibrate the temperature signal receiving unit H3 so that the temperature value shown in the output unit H6 matches the predetermined temperature of the calibration temperature signal output from the temperature signal output means THM.

Further, if a pseudo temperature signal output circuit as shown in FIG. 3 that generates a pseudo temperature signal as a pseudo temperature sensor is used instead of the temperature sensor TD as the temperature signal output means THM, the simulator 1 for a corioli flow meter can be used. It is possible to generate an arbitrary calibration temperature signal without actually changing the temperature of the environment in which it is placed. By sequentially changing a predetermined temperature, the calibration temperature signal is converted from the temperature signal output means THM. It is output to the temperature signal receiving unit H3 of H. The temperature signal receiving unit H3 calculates the temperature value to be sequentially changed from the temperature signal for calibration which is sequentially changed, and outputs the temperature value to the phase difference / frequency calculation unit H4.

The phase difference / frequency calculation unit H4 calculates the phase difference and frequency corrected according to the temperature values that are sequentially changed from the input phase shift sine wave signal and sine wave signal. The calculated phase difference and frequency are input to the flow rate / density calculation unit H5 in accordance with the temperature values that are sequentially changed, and the flow rate of the fluid is calculated from the phase difference and the density of the fluid is calculated from the frequency. The temperature value that is sequentially changed and the flow rate and density of the fluid calculated corresponding to the temperature value are combined and output to the output unit H6. The worker of the calibration process can check the temperature fluctuation characteristic of the conversion unit H by referring to the output of the flow rate and the density which fluctuates according to the temperature.

FIG. 7 is a block circuit configuration diagram of a Koriori flow meter having a built-in Koriori flow meter simulator of the embodiment, and the Koriori flow meter simulator 1 "" is provided inside the conversion unit H'of the Koriori flow meter. In FIG. 7, in order to make the drawing easier to see, the wiring on the ground side is omitted from the wiring of the analog signal, and only the wiring connected to the ground potential is shown.

The Coriolis flowmeter simulator 1 "'is provided with an input signal switching unit 6 connected to the output side of the simulated signal output unit 5. Input signal switching is performed on the channel CH1 output terminal of the simulated signal output unit 5. The input terminal 6a1 of the changeover switch 6a of the unit 6 is connected, and the input terminal 6b1 of the changeover switch 6b of the input signal changeover unit 6 is connected to the channel CH2 output terminal of the simulated signal output unit 5. Input of the changeover switch 6a. The upstream vibration detection coil L2 of the detection unit K is connected to the terminal 6a2, and the output terminal 6ao of the changeover switch 6a is an input terminal of the upstream coil signal reception circuit H2a of the coil vibration reception circuit unit H2 of the conversion unit H. The connection destination of the upstream coil signal receiving circuit H2a can be switched to the channel CH1 output terminal of the simulated signal output unit 5 or the upstream vibration detection coil L2 by the changeover switch 6a.

On the other hand, the downstream vibration detection coil L3 of the detection unit K is connected to the input terminal 6b2 of the changeover switch 6b, and the downstream coil of the coil vibration receiving circuit unit H2 of the conversion unit H is connected to the output terminal 6bo of the changeover switch 6b. The input terminal portion of the signal receiving circuit H2b is connected. The connection destination of the downstream coil signal receiving circuit H2b can be switched to the output terminal of the channel CH2 of the simulated signal output unit 5 or the downstream vibration detection coil L3 by the changeover switch 6b.

Further, these changeover switches 6a and changeover switches 6b are connected so that the changeover operation is performed in conjunction with each other, and are configured to be switched from terminals 6a1 and 6b1 to terminals 6a2 and 6b2 at the same time, respectively. ..

Further, the temperature sensor TD of the detection unit K is connected to the temperature sensor input end of the temperature signal reception unit H3 of the conversion unit H. Although the input side of the A / D conversion unit 3 is connected to the downstream vibration detection coil L3 of the detection unit K in FIG. 7, the configuration may be such that the input side is connected to the upstream vibration detection coil L2. Since the other configurations of the Coriolis flow meter simulator 1 "" and the connection state between the conversion unit H and the detection unit K are the same as those of the Coriolis flow meter simulator 1 "in the second embodiment, the description thereof will be omitted.

In the Koriori flow meter having a built-in simulator for the Koriori flow meter configured in this way, when performing normal flow measurement, the changeover switch 6a of the input signal switching unit 6 is switched to the input terminal 6a2 side, and the conversion unit H The upstream coil signal reception circuit H2a of the above is interlocked with the upstream vibration detection coil L2 of the detection unit K, and the changeover switch 6b is switched to the input terminal 6b2 side, and the downstream coil signal reception circuit H2b of the conversion unit H is the detection unit. It is in a state of being connected to each of the downstream vibration detection coils L3 of K. Then, when performing calibration processing or operation check of the conversion unit H', the changeover switch 6a of the input signal switching unit 6 is switched to the input terminal 6a1 side, and the upstream coil signal reception circuit H2a of the conversion unit H outputs a simulated signal. The changeover switch 6b is switched to the input terminal 6b1 side in conjunction with the output terminal of the channel CH1 of the unit 5, and the coil signal reception circuit H2b on the downstream side of the conversion unit H is connected to the output terminal of the channel CH2 of the simulated signal output unit 5. Change to the connected state.

Regarding the actual operation when performing the calibration process, from the vibration of the tube body P of the detection unit K by the drive circuit H1 of the conversion unit H to the time when the sine wave signal is input to the A / D conversion unit 3. Since it is the same as that of the second embodiment and is the same as that of the first embodiment after the sine wave signal is input to the A / D conversion unit 3, the description thereof will be omitted.

In this way, by providing the Coriolis flowmeter simulator 1 "'" inside the conversion unit H, the conversion unit H and the detection unit K of the Coriolis flowmeter are separated as in the first embodiment, and then the Coriolis flowmeter simulator 1 "" is separated. The work of connecting 1 to the conversion unit H becomes unnecessary. By simply switching the changeover switches 6a and 6b of the input signal switching unit 6, the normal flow rate measurement can be easily shifted to the calibration process or the operation check of the conversion unit H'. be able to.

The characteristics of the converter of the Koriori flow meter are generally easily changed by external noise, and the characteristics are significantly impaired by the generation of surge current due to lightning strikes, etc. Therefore, the simulator 1 "'for the Koriori flow meter is built-in. , It is very useful because the calibration process with high reproducibility can be performed as appropriate.

By using the Koriori flow meter simulator 1, 1', 1 ", 1" "according to the present invention and the Koriori flow meter with a built-in simulator, the simulated phase signal of the fluid set to a predetermined flow rate can be detected by the Koriori flow meter. It is possible to stably output to the conversion unit H of the Koriori flow meter with high reproducibility without actually flowing a fluid through the unit.

Further, by using the simulated phase signal for the calibration process of the conversion unit H, it is possible to correct the variation based on the calibration for each Coriolis flow meter. Further, the calibration process can be performed inexpensively and in a short time without actually flowing the fluid through the detection unit of the Coriolis flow meter.

1, 1', 1 ", 1""Simulator for Koriori flow meter 2 Sine wave transmitter 2a Frequency setting unit 2b Sine wave generation unit 3 A / D conversion unit 4 Phase shift unit 4a Phase angle setting unit 4b Phase shift signal generation Part 5 Simulated signal output part 6 Input signal switching part H Conversion part H1 Drive circuit H2 Coil vibration receiving circuit part H2a Upstream side coil signal receiving circuit H2b Downstream side coil signal receiving circuit H3 Temperature signal receiving part K Detection part L1 Drive coil L2 Upstream Side vibration detection coil L3 Downstream side vibration detection coil P Tube TD Temperature sensor THM Temperature signal output means

The simulator for a Koriori flow meter according to the present invention for achieving the above object can be connected to the conversion part of the Koriori flow meter including a detection part and a conversion part attached to a tube body through which the fluid to be measured flows. A simulated signal output unit that outputs a simulated phase signal during calibration , a sinusoidal digital data generator that generates sinusoidal digital data, and a phase in which the sinusoidal digital data is input and the phase is shifted based on a set phase angle. A simulator for a Corioli flow meter including a phase shift unit that outputs shift sinusoidal digital data , wherein the conversion unit is a pair of vibrations arranged upstream and downstream of the tube body that vibrates by the drive coil of the detection unit. It has a coil vibration receiving circuit unit for connecting a detection coil, and the simulated signal output unit converts the input sine wave digital data and the phase shift sine wave digital data into an analog signal and synchronizes them as the simulated phase signal. It has a pair of input / output terminals for output, and the sine wave digital data output from the sine wave digital data generation unit is directly input to one input terminal of the simulated signal output unit, and the sine wave digital data is directly input to the other input terminal. Inputs the phase-shifted sinusoidal digital data whose phase is shifted from the sinusoidal digital data output from the sinusoidal digital data generation unit via the phase shift unit, and inputs the pair of phase-shifted sinusoidal digital data to the coil vibration receiving circuit unit. Instead of connecting the vibration detection coil, a pair of output terminals of the simulated signal output unit are connected.
Further, the simulator for a Koriori flow meter according to the present invention can be connected to the conversion part of the Koriori flow meter provided with a detection part and a conversion part attached to a tube body through which the fluid to be measured flows, and a simulated phase signal at the time of calibration. A simulator for a mass flow meter equipped with a simulated signal output unit and a simulated temperature sensor, wherein the conversion unit is a pair arranged upstream and downstream of the tube body vibrated by the drive coil of the detection unit. The coil vibration receiving circuit unit for connecting the vibration detection coil and the temperature sensor input end portion for connecting the temperature sensor of the detection unit are provided, and the coil vibration receiving circuit unit is replaced with the vibration detection coil. It is characterized in that a simulated signal output unit is connected and the pseudo temperature sensor is connected to the temperature sensor input end instead of connecting the temperature sensor.

Claims (8)

A Corioli that can be connected to the conversion unit of a Corioli flow meter that includes a detection unit that attaches a fluid to be measured to a tube that flows inside and a conversion unit, and that has a simulated signal output unit that outputs a simulated phase signal during calibration. A simulator for flow meters
The conversion unit has a coil vibration receiving circuit unit that connects a pair of vibration detection coils arranged upstream and downstream of the tube body that vibrates by the drive coil of the detection unit.
A simulator for a Koriori flow meter, characterized in that the simulated signal output unit is connected to the coil vibration receiving circuit unit instead of connecting the vibration detection coil. It has a sine wave digital data generator that generates sine wave digital data, and a phase shift unit that inputs the sine wave digital data and shifts the phase based on the set phase angle and outputs the sine wave digital data. And
The simulated signal output unit has a pair of input / output terminals that convert the input sine wave digital data and the phase shift sine wave digital data into analog signals and output them synchronously as the simulated phase signal.
The sine wave digital data output from the sine wave digital data generation unit was directly input to one input terminal of the simulated signal output unit, and output from the sine wave digital data generation unit to the other input terminal. The simulator for a corioli flow meter according to claim 1, wherein the phase-shifted sine wave digital data whose phase is shifted by inputting the sine wave digital data via the phase shift unit is input. The simulator for a corioli flow meter according to claim 2, wherein the sine wave digital data generation unit includes an A / D conversion unit that converts a sine wave signal, which is an input analog signal, into sine wave digital data. The third aspect of claim 3, wherein the sine wave digital data generation unit includes a sine wave transmission unit that generates the sine wave signal corresponding to a frequency simulating a fluid and outputs the sine wave signal to the A / D conversion unit. Koriori flow meter simulator. The claim is characterized in that the A / D conversion unit is connected to any one of the pair of vibration detection coils of the detection unit, and a sine wave signal which is an analog signal is input from the vibration detection coil. The simulator for the Koriori flow meter according to 3. Has a pseudo temperature sensor,
The conversion unit has a temperature sensor input end for connecting the temperature sensor of the detection unit.
The simulator for a Koriori flow meter according to any one of claims 1 to 5, wherein the pseudo temperature sensor is connected to the temperature sensor input end instead of connecting the temperature sensor. A conversion unit having a detection unit attached to a pipe body through which the fluid to be measured flows, and a coil input end portion connecting a pair of vibration detection coils arranged upstream and downstream of the pipe body vibrating by the drive coil of the detection unit. In a Koriori flow meter with a built-in simulator that calculates the flow rate and density of the fluid flowing through the tube.
A Coriolis flow meter simulator is placed between the pair of vibration detection coils and the input end.
The simulator for the Koriori flow meter inputs an A / D conversion unit that converts a sine wave signal from one of the pair of vibration detection coils into sine wave digital data, and the sine wave digital data. , A phase shift unit that outputs phase-shifted sine wave digital data whose phase is shifted based on a set predetermined phase angle, and inputs the sine wave digital data and the phase-shifted sine wave digital data, and two said sine waves. It is possible to switch between the simulated signal output unit that converts to a signal and outputs it as a simulated phase signal and the input of the simulated phase signal or the input of the vibration detection coil, and outputs either one of the inputs to the input end. A corioli flow meter with a built-in simulator, which is characterized by having a switching unit. The sine wave digital data is directly connected from the A / D conversion unit and input to the simulated signal output unit, and the phase shift sine wave digital data is transmitted from the A / D conversion unit via the phase shift unit. The corioli flow meter having a built-in simulator according to claim 7, wherein the data is input to the simulated signal output unit.

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