JP4441627B2 - Pressure sensor dynamic calibration apparatus and dynamic calibration method - Google Patents

Description

  The present invention relates to a dynamic calibration device and a dynamic calibration method for a pressure sensor using a pressure-reducing device that compresses or expands a gas or a liquid using inertial force of a weight.

  The calibration of the pressure sensor has conventionally been performed only statically. A typical example is a weight type pressure calibration device. This is based on the principle that static pressure is generated inside the cylinder using a weight.

  As described in Non-Patent Document 1, in order to dynamically calibrate the pressure sensor, it is necessary to generate a dynamic pressure. An example is shown in FIG. As this method, the weight of the weight type pressure gauge was suddenly removed to change the pressure, or the valve was suddenly opened and closed. This method is 1) low reproducibility of valve opening and closing, and it is difficult to accurately define the pressure change applied to the pressure sensor as a function of time, so the calibration result is only a guide 2) In the direction of decreasing pressure However, there are basic drawbacks such as being incompatible with the use of dynamic pressure in industry.

  Further, as described in Non-Patent Document 2, a method using a motion generator employs a technique as shown in FIG. Although this method allows absolute calibration, it has the following drawbacks. 1) Generally, it is difficult to lower the frequency. 2) It is difficult to increase the frequency in terms of resonance and damping of the liquid column. 3) Furthermore, the pressure fluctuation amplitude is increased. It is difficult.

In particular, as described in Non-Patent Document 3, the method shown in FIG. 11 has been performed in the past as a method for generating a sine wave fluctuation pressure. This method has the basic problem that 1) it is only comparative calibration, not absolute calibration. 2) Since the pressure sensor used as a reference is only static calibration, There is a basic flaw that does not become.
New edition weighing technology handbook Corona 1987, 916P, 12.6 Weight type pressure gauge ENDEVCO “DYNAMIC PRESSURE MEASUREMENT TECHNOLOGY” P / N 30096 Report from the University of Tokyo Aerospace Research Institute Vol. 9 No. 1 (A) January 1973, Takeshi Asanuma et al. Japanese Patent Application No. 2003-123417

  It is an object of the present invention to dynamically calibrate a pressure sensor so that the pressure change measured by the pressure sensor can be accurately defined as a function of time and the pressure can be increased or decreased.

  By using the present invention, the following effects can be expected.

According to the present invention, the pressure to be measured by the pressure sensor can be accurately defined, and the pressure sensor can be dynamically calibrated while the pressure can be increased or decreased.

  Further, the pressure increasing / decreasing device for causing the pressure sensor to measure the pressure can be realized with a simple configuration of a cylinder and a piston.

  In addition, the pressure to be measured by the pressure sensor using the laser interferometer can be accurately defined.

  In addition, the pressure to be measured by the pressure sensor can be accurately defined using a small device called an acceleration sensor.

  Even when a small device called an acceleration sensor is used, the pressure to be measured by the pressure sensor can be accurately defined as in the case of using a laser interferometer.

  In addition, since the reference pressure sensor calibrated accurately by the calibration apparatus of the present invention is used, accurate calibration is possible with a simple configuration.

  Further, since the pressure limited to the inertia force in the vertical direction can be used, the pressure to be measured by the pressure sensor can be defined more accurately.

  In addition, the above calibration can be performed more accurately.

  In addition, even when using an acceleration sensor, a pressure limited to the inertia force in the vertical direction can be used, so that the pressure to be measured by the pressure sensor can be defined more accurately.

  Further, since the pressure limited to the inertia force in the vertical direction can be used, the pressure to be measured by the pressure sensor can be defined more accurately.

  It is also possible to monitor whether the pressure is limited to the inertia force in the vertical direction.

  In addition, since the strain gauge is used to monitor whether the pressure is limited to the inertia force in the vertical direction, the apparatus can be configured simply.

  In addition to the inertial force, a bias pressure due to the restoring force is applied, so that measurement beyond the region of only the inertial force can be performed.

  In addition, the bias pressure can be freely changed, and the measurement region can be freely set.

  In addition, a wider range of the bias can be applied.

  Further, calibration can be performed using the inertial force in a wider frequency region by using the resonance phenomenon.

  In addition, the pressure sensor can be calibrated by removing the parasitic frequency characteristics.

  In addition, the pressure sensor can be calibrated while reducing the friction between the piston and the cylinder.

  As a method for generating dynamic pressure, inertial force generated when mass is moved is used. The mass can be measured with high accuracy, and in the usage situation of the present invention, there is no difference in measurement accuracy between static measurement and dynamic measurement. Therefore, the inertial force measurement accuracy depends on the motion measurement accuracy. Therefore, if the primary standard is used, the motion is measured with high accuracy using a laser interferometer, as in the case of the vibration and shock measurement standard. If the measurement is performed as a secondary standard, the movement is measured by an acceleration sensor calibrated with an interferometer. Furthermore, in order to compare a pressure sensor whose dynamic characteristics were evaluated with a laser interferometer or an accelerometer or acceleration sensor calibrated with a laser interferometer, and the pressure sensor to be calibrated, the same pressure that changes over time is used. It is also possible to measure and calibrate by obtaining the frequency characteristics of the pressure sensor to be calibrated.

  In the present invention, vibration is used as a method for generating inertial force, but the mass of the pressure generating weight, the required frequency band of vibration, the mechanism of the piston cylinder device used as a pressure increasing / decreasing device for generating dynamic pressure, and its In consideration of the height, a small shaking table used for calibrating the acceleration pickup is not sufficient. In addition, there is a high possibility that the shaking table will deviate from vertical linear motion due to the moment due to the deviation of the center of gravity. For this reason, it is necessary to use an oscillating motion generator capable of controlling to cancel the moment.

  Next, the means or method for obtaining the frequency characteristics of the pressure sensor will be described more specifically below.

  First, the first invention is a pressure sensor calibration device, 1) a pressure increasing / decreasing device that compresses or expands gas or liquid using inertial force of a weight, and 2) pressure increasing / decreasing by the pressure increasing / decreasing device. A pressure sensor for measuring the pressure of the gas or liquid, 3) a motion generator for applying an inertial force to the weight, and 4) a table of the motion generator for installing the pressure adjusting device and the pressure sensor. And 5) a first measuring instrument for measuring the movement state of the weight, 6) a second measuring instrument for measuring the movement state of the table, and 7) from these measured movement states, 8) calculating means for deriving the reduced pressure, and 8) inducing the movement of the weight by the movement of the table to dynamically change the pressure to be measured by the pressure sensor, Pressure data derived from It is intended to calibrate the pressure sensor is compared with the value derived from the signal value or the signal value of. Here, the dynamic change is a negative change of the quasi-static change.

  Further, the second invention is a pressure sensor calibration apparatus, wherein 1) the pressure increasing / decreasing apparatus seals a cylinder filled with a gas or fluid with a piston, and 2) on the piston (or cylinder). 3) Fix the cylinder (or the biston) to the table, 4) Set the piston-cylinder system and the weight on the table of the motion generator, and 5) By the movement of the table Sinusoidal vibration, random vibration, and impulse motion are given to the weight, and the above-described gas or fluid is pressurized or decompressed using the resultant inertial force.

  Further, a third invention is a pressure sensor calibration apparatus, wherein 1) the first measuring instrument and the second measuring instrument are laser interferometers, and 2) the calculating means includes: The inertial force acting on the pressure medium inside the cylinder is determined, and the inertial force is divided by the area of the piston to determine the pressure to be measured by the pressure sensor.

The fourth invention is a pressure sensor calibration device, wherein the first measuring instrument and the second measuring instrument are acceleration sensors, and inertial force is obtained from measurement using these acceleration sensors. First, the inertial force is divided by the area of the piston to determine the pressure to be measured by the pressure sensor.

  The fifth invention is a pressure sensor calibration device, wherein the acceleration sensor is an acceleration sensor calibrated using the dynamic calibration device.

The sixth invention is a pressure sensor calibration device, wherein an acceleration sensor as a first measuring instrument is fixed to the weight.

  The seventh invention is a pressure sensor calibration device, wherein the pressure sensor calibrated by the pressure sensor calibration device is a reference pressure sensor, and compresses or expands gas or liquid using inertial force of a weight. A configuration for causing the reference pressure sensor and the pressure sensor to be calibrated to measure the pressure of the gas or liquid pressurized or depressurized by the pressure increasing / decreasing device, and applying an inertial force to the weight A motion generator, and a table of the motion generator on which the pressure adjusting device, the reference pressure sensor and the pressure sensor to be calibrated are installed, and the motion of the table induces the motion of the weight. Thus, the pressure to be measured by the reference pressure sensor and the pressure sensor to be calibrated is dynamically changed, and the pressure sensor to be calibrated is dynamically calibrated by comparison with the reference pressure sensor. It is intended to be.

  The eighth invention is a pressure sensor calibration apparatus, wherein the motion generator includes a vertical actuator and a horizontal actuator, and measures the actual motion of the table in two or three dimensions. In order to minimize the error between the actual movement of the table and the target value, the signal from the horizontal acceleration sensor of the table is fed back to the horizontal actuator to control the horizontal movement. It is.

  In the ninth invention, an acceleration sensor whose sensitivity is defined by a matrix is used as the acceleration sensor.

  The tenth invention is a pressure sensor calibration apparatus, wherein the motion generator includes a vertical actuator and a horizontal actuator, the sensitivity of the horizontal actuator is defined by a matrix, and the weight Control is performed so as to suppress lateral movement of the table by a signal from an acceleration sensor provided above.

  An eleventh aspect of the invention is a pressure sensor calibration device, wherein the relative movement direction of the piston and the cylinder is a vertical line direction, and the piston is not fixed to the vibration table generated by the relative movement. A line connecting the point of action of the total force applied to the part or the cylinder part and the center of gravity of the piston part or the table part is on the vertical line.

  A twelfth aspect of the present invention is a pressure sensor calibration device, wherein a rotational moment sensor is provided between the table and the pressure-increasing / decreasing device, and the table portion is arranged so that the output signal of the rotational moment sensor is reduced. By controlling the movement, the relative movement direction of the piston and the cylinder is maintained in the vertical direction.

  A thirteenth aspect of the present invention is a pressure sensor calibration device in which a strain gauge operating as a rotational moment sensor is provided between the table and the pressure-increasing / decreasing device, so that the strain detected by the strain gauge is reduced. Thus, by controlling the movement of the table portion, the relative movement direction of the piston and the cylinder is maintained in the vertical direction.

A fourteenth aspect of the invention is a pressure sensor calibration device comprising a configuration in which a bias force is superimposed by a restoring force in addition to the inertia force in the direction of the inertia force by the weight or in the opposite direction. To do.

  According to a fifteenth aspect of the present invention, there is provided a pressure sensor calibration apparatus comprising a configuration for adjusting the restoring force and adjusting the bias force.

  The sixteenth invention is a pressure sensor calibration apparatus, wherein the restoring force has a non-linear characteristic.

  The seventeenth aspect of the invention is a pressure sensor calibration device, wherein the motion generator is driven at the resonance frequency of the weight of the pressure increasing / decreasing device or the frequency at which the motion of the weight resonates, and calibration is performed in a resonant state. It is what you want to do.

  An eighteenth aspect of the invention relates to a pressure sensor calibration method. 1) Pressure is increased or decreased by a pressure / pressure device for compressing or expanding a gas or liquid pressure medium using the inertial force of a weight, and the pressure / pressure device. Further, a pressure sensor for measuring the pressure of the gas or liquid, a motion generator for applying an inertial force to the weight, a table of the motion generator for installing the pressure increasing / decreasing device and the pressure sensor, A first measuring instrument for measuring the movement state of the weight of the first, a second measuring instrument for measuring the movement state of the table, and a calculation means for deriving the pressurized pressure from the measured movement state. And the movement of the table induces the movement of the weight and changes the pressure measured by the pressure sensor, and the pressure data derived from the calculation means and the signal value of the pressure sensor or The signal value In the pressure sensor calibration apparatus, the pressure sensor is calibrated by comparing with a derived value. 2) The pressure medium is removed from the pressure increasing / decreasing apparatus, and the pressure medium is weighted. 3) The frequency characteristics of the pressure sensor evaluated in a state where no inertial force is applied. 3) The pressure sensor evaluated in the state where the pressure medium is set inside the cylinder and the inertial force of the weight is applied to the pressure medium. The frequency response characteristic of the pressure sensor is obtained by subtracting from the frequency characteristic.

  According to a nineteenth aspect of the present invention, there is provided a pressure sensor calibration method comprising: 1) a cylinder and a piston, and a pressure increasing / decreasing device that compresses or expands a gas or liquid pressure medium using inertial force of a weight; A pressure sensor that measures the pressure of the gas or liquid that has been pressurized or depressurized by a device, a motion generator that applies inertial force to the weight, and a motion generator that installs the pressure / pressure device and the pressure sensor Table, a first measuring instrument for measuring the movement state of the weight, a second measuring instrument for measuring the movement state of the table, and the pressure increased or decreased from the measured movement state. A calculation means for deriving, inducing the movement of the weight by the movement of the table, changing the pressure to be measured by the pressure sensor, the pressure data derived from the calculation means, Pressure sensor In the pressure sensor calibration device, the pressure sensor is calibrated by comparing the signal value of the signal or a value derived from the signal value. 2) The piston and the cylinder are relatively rotated. However, the frequency characteristic of the pressure sensor is measured.

  Embodiments of the present invention will be described below in detail with reference to the drawings. In the following description, devices having the same function or similar functions are denoted by the same reference numerals unless there is a special reason. Further, the present invention is applicable to a wide range without being limited to the following description and drawings.

As shown in FIG. 1, the pressure sensor calibration apparatus of the present invention is fixed to a cylinder 3 fixed on a table 6 of a motion generator that performs sinusoidal vibration, random vibration, or impulse movement, and a weight 1. A pressure gauge or a pressure sensor sensor 4 is used to measure pressure by using a pressure or a pressure-reduced state generated in a gas or liquid that is a pressure transmission medium 9 by a piston. The table 6 of the motion generator is irradiated with the laser light 8 from the laser interferometer, and the motion state is accurately measured. The pressure gauge or pressure sensor 4 to be calibrated is pressurized by a gas or liquid pressure medium.

  In FIG. 1, the cylinder 3 is fixed to the table 6 of the motion generator. However, it is obvious that the piston 2 and the cylinder 3 may be exchanged to fix the piston 2 as shown in FIG. 2. is there. The merit of this method is that it becomes possible to generate a dynamic pressure having a larger amplitude. This is because the mass contributing to dynamic pressure generation can be increased as a breakdown of the mass of the structure mounted on the shaking table. Therefore, if the acceleration that the shaking table can generate is constant, This is because a dynamic pressure having a larger amplitude can be generated within the allowable dynamic load range. In addition, it is not essential that the pressure transmission medium 9 is pressurized in a pressure chamber formed by a piston and a cylinder, and it is important that a closed pressure chamber is formed, and a bag-shaped medium is also used. Can do. If a sealed chamber having a movable wall is formed, it can be applied to the present invention in principle.

Here, a _d (t) represents an acceleration acting on the piston or the weight of the gas or liquid pressure propagation medium 9 in the pressure chamber, and a _T (t) represents a motion acceleration of the table of the motion generator. when a, the mass of the weight m _d, the piston in the case of FIG. 1, the mass of the cylinder in the case of FIG. 2 as m _s, inertial forces,

で表される。シリンダの面積をＳとすると、慣性力による圧力変動は、

It is represented by When the area of the cylinder is S, the pressure fluctuation due to the inertial force is

This signal is an input signal to the pressure sensor. It is an object of the present invention to examine how the pressure sensor output signal fluctuates in response to this pressure fluctuation, to clarify and calibrate the dynamic characteristics of the pressure sensor.

  In the example of FIG. 1, a laser interferometer is used to accurately measure the motion of the table 6 of the motion generator, but this is not essential, and as shown in FIG. It is also possible to calibrate by measuring the same physical state (for example, pressure) between the gauge or pressure sensor 11 and the pressure gauge or pressure sensor 4 to be calibrated. Although it is not shown in the drawing that it can be calibrated with a reference pressure gauge or pressure sensor, the same applies to the calibration device of FIG.

Further, the calibration device shown in FIG. 1, FIG. 2, or FIG. 3 is configured such that pressure is generated in the pressure transmission medium 9 by the inertial force due to the relative motion of the piston, the weight fixed thereto, and the cylinder. However, as shown in FIG. 4, when a spring having a restoring force or a spring mechanism 14 is used in combination, a bias pressure can be applied to the pressure transmission medium 9, and only the above inertial force is used. Compared to, the measurement range can be easily expanded. Generally, the restoring force of a spring is proportional to the displacement, but it is not limited to a spring having such a linear response characteristic, and it is easy to use a bias pressure range by using a spring having a non-linear response characteristic. It may be possible to set as follows. The spring mechanism 14 of the calibration device shown in FIG. 4 is provided in a pressurizing chamber filled with compressed gas so that a bias pressure by the compressed gas can be applied to the piston in addition to the force of the spring. It has become. FIG. 5 shows a biasing pressure applied by the spring mechanism 14 or compressed gas pressure to the calibration device of FIG.

The calibration apparatus of FIGS. 4 and 5 relates to the fifteenth, sixteenth or seventeenth inventions. The case where bias pressure is applied by a method other than gravity as described above is considered as follows. The gravitational acceleration is g _L , the downward force generated by the spring is F _S (t), the acceleration of the motion of the weight due to the sine vibration generated by the motion generator is a _d (t), and the motion acceleration of the table of the motion generator is Assuming that a _T (t), it is possible to cause the pressure sensor to measure the fluctuating pressure with a single amplitude within a range where the following expression is satisfied.

  In this case, in a state before the weight starts to move by the motion generator, if the cross-sectional area of the cylinder is S,

The static pressure F is applied.

Next, embodiments according to the first, second, seventh to nineteenth inventions will be described.
First, in general measurement, a sine wave burst signal is often used. In this case, the output signal of the pressure sensor is also a burst signal. That is, a sine burst signal generated by a motion generator (a waveform in which a signal for one period of a sine wave having a period T _i = 2π / ω _i , ω _i = 2πf _i , and a frequency = f _i is continuous for a plurality of periods) Accordingly, the acceleration waveform of the weight also becomes a burst signal.

Therefore, in the general case, the motion acceleration waveform of the weight measured by the laser interferometer is a _dL (t) in the section where the weight is most stably moving, and the table of the motion generator measured by the laser interferometer. The motion acceleration waveform is described as a _TL (t). Assuming that the output signal of the pressure sensor at this time is p _L (t), the output signal of the pressure sensor in a no-load state is n _sL (t), and the sectional area of the cylinder is S, the following equation is established.

Equation 5 represents the dynamic pressure to be measured by the pressure sensor generated by the inertial force of the weight and the cylinder, and Equation 6 represents the pressure due to the fluctuating pressure in consideration of the output signal from the pressure sensor when there is no load. This is an output signal of the sensor. If n _s (t) is small enough to be ignored, the second term on the right side of Equation 6 may be omitted. If the input signal and the output signal can be clearly defined, both the input signal and the output signal are changes from the equilibrium point. Therefore, according to the definition of the transfer function, the transfer function G _L (σ) of the pressure sensor is expressed by the following equation: Defined by

Ｌはラプラス変換、σはラプラス変換パラメータである。

L is a Laplace transform, and σ is a Laplace transform parameter.

Next, embodiments according to the third, fourth, fifth, seventh to nineteenth inventions will be described.
In the section where the weight is most stably moving, the motion acceleration waveform of the weight measured by the acceleration sensor is a _dA (t), and the motion acceleration waveform of the table of the motion generator measured by the acceleration sensor is a _TA (t) , And are described. If the output signal of the pressure sensor at this time is p _{in, A} (t), p _{out, A} (t), and the output signal of the pressure sensor in the no-load state is n _sA (t), the following equation holds: To do.

Equation 8 represents the dynamic pressure that is measured by the pressure sensor generated by the inertial force of the weight and the cylinder, and Equation 9 is a pressure sensor based on fluctuating pressure in consideration of an output signal from the pressure sensor when there is no load. Output signal. If n _sA (t) is small enough to be ignored, the second term on the right side of _Equation 9 may be omitted. If the input signal and the output signal can be clearly defined, both the input signal and the output signal are changes from the equilibrium point. Therefore, according to the definition of the transfer function, the transfer function G _A (σ) of the pressure sensor is expressed by the following equation: Defined by

Ｌはラプラス変換、σはラプラス変換パラメータである。

L is a Laplace transform, and σ is a Laplace transform parameter.

Next, a method for obtaining the frequency response characteristics of the pressure sensor to be calibrated will be described, which relates to the sixth to eighteenth aspects of the invention and is compared with the result measured by the reference pressure sensor.

The dynamic response characteristic of the reference pressure sensor is obtained by measuring the motion acceleration of the weight and the motion acceleration of the table of the motion generator with a laser interferometer. Therefore, in the configuration as shown in FIG. 2, it can be assumed that the transfer function of the acceleration sensor is known. Therefore, the output signal of the reference acceleration sensor is p _R (t), the transfer function is G _R (σ), the output signal of the reference pressure sensor at no load is n _sR (t), and the reference pressure sensor is dynamically measured. When the pressure signal is p _iR (t), the following equation is established.

The output signal of the pressure sensor to be evaluated is p _tc (t), the no-load output signal of the pressure sensor to be evaluated is n _st (t), and the transfer function of the pressure sensor to be evaluated is G _t Assuming (σ), the following formula is established.

When L [p _iR (t)] is deleted in Equations 11 and 12, the following equation is obtained. That is, the transfer function of the pressure sensor can be obtained from the output signal of the reference pressure sensor, the known transfer function of the reference pressure sensor, and the output signal of the pressure sensor to be evaluated.

An overall image of the pressure sensor calibration device of the present invention including the drive device and the control system can be configured as shown in FIG. 6, for example. In this configuration, a mirror 17 and an acceleration sensor 7 for reflecting a laser beam 8 from a laser interferometer that measures a movement state of a vertical weight are provided on a weight 2 that also serves as a piston. The double weight 2 is housed in a cylinder 3, and the cylinder and the piston pressurize and depressurize the pressure propagation medium 9 in the pressure chamber, and cause the pressure gauge or pressure sensor 4 to measure the pressure. When the liquid pressure propagation medium 9 is injected into the pressure chamber, it is desirable that no gas remain in the pressure chamber and the pressure propagation medium. The valve 32 is an exhaust hole for preventing gas from remaining in the pressure chamber, and is also an exhaust hole for removing bubbles by pouring excess liquid to be injected. The cylinder 3 vibrates due to the motion of the table 6 of the motion generator, and the pressure propagation medium 9 in the pressure chamber is increased or decreased by this vibration. The table 6 of the motion generator is driven by an actuator 19 for the X-axis direction, an actuator 20 for the Y-axis direction, and an actuator 21 for the Z-axis direction. The motion state of the table 6 of the motion generator is determined by the laser light from the corner cube 18, the laser interferometer 22 for the X-axis direction, the laser interferometer 23 for the Y-axis direction, or the laser interferometer 24 for the Z-axis direction. Irradiate and measure.

  The push-pull type actuators 20 and 38 for the Y-axis direction in FIG. 6 are also used to remove the influence of the movement of the piston 2 when a slight movement in the horizontal direction other than the gravitational direction is observed. If there is such an effect, it is desirable to eliminate this effect because the calibration by the motion in the direction of gravity does not become a correct value. To eliminate this effect, the sensitivity of the acceleration sensor used to control the motion generator can be defined in a matrix, the control transfer function of the shaking table can be expressed in a matrix, and the motion of the mounting table can be expressed in a matrix. Detect with higher sensitivity and accuracy than when using an undefined acceleration sensor, and use the values of non-diagonal matrix elements as feedback signals so that the non-diagonal components disappear, and the X and Y axes The direction actuators 19 and 38 are controlled. By this control, the influence of horizontal movement can be suppressed.

  Measurement data from the above laser interferometer, accelerometer, or acceleration sensor, or measurement data from a reference pressure sensor or reference pressure gauge in the case of using a reference pressure sensor or reference pressure gauge, is sent to the signal processing device 25 through the interface 27. The signal processing device 25 also controls each of the actuators described above to cause a pressure gauge or pressure sensor to be calibrated to measure a predetermined pressure or pressure change.

  Further, the signal processing device 25 detects a lateral motion component due to the rotation of the cylinder from the measurement data from the laser interferometer, the accelerometer or the acceleration sensor, and is provided as an actuator 19 for the X-axis direction or as an auxiliary. The Y-axis direction actuator 38 is controlled to suppress this lateral movement component.

  Generally, friction is generated between the weight 1 that also serves as a piston and the cylinder 3, but by measuring while rotating the weight 1 that also serves as a piston, the vertical component of this friction can be suppressed. . In this case, it is desirable to provide a mirror 17 that reflects laser light at the center of the weight 1 that also serves as a piston. FIG. 7 is a configuration for this purpose. There is a gear serving as a weight at the upper portion of the piston, and there is a gear fixed to the rotating shaft of the motor in contact with the gear, and thus can be rotated by driving the motor. There are various other mechanisms that can be used to rotate the piston, and although not shown in the figure, it is easy to electromagnetically rotate the gear as a rotor. It can also be rotated by blowing high-pressure air. Further, since the gear continues to rotate for a while due to inertia even when the drive device is stopped, the drive can be interrupted during the measurement for calibration.

FIG. 8 shows a configuration in which the piston portion is disposed on the vibration table side and the cylinder portion is disposed on the upper portion thereof. The rotary table on which the piston portion is mounted is provided with a gear, which is driven through a gear attached to the rotation shaft of the motor. Further, in order to stop the rotation of the cylinder portion, a pin is taken out from the cylinder portion, and this is passed through a guide fixed from the outside so as to move only in the vertical direction. Further, it is clear that even if the vertical relationship between the cylinder part and the piston part is reversed, this is not a fatal problem.
(End of Example 4)

When liquid (for example, oil) is used as a pressure transmission medium, if bubbles enter, the movement of the weight cannot be transmitted as pressure, and correct calibration cannot be performed. Therefore, in order to check the presence or absence of bubbles, the following may be performed.
1) When the cross-sectional area of the cylinder is S and the piston is moved from top to bottom by d and the drain is opened, the weight of oil that comes out when the density is ρ ₀ is the product, ρ ₀ Sd, If it is far from, it can be concluded that the influence of bubbles is large.
2) If there is a noticeable effect when the oil is cooled, it is concluded that there is an effect of bubbles.

  In addition, when liquid as a pressure propagation medium leaks from the gap between the relatively rotating piston and the cylinder, a sealing such as a piston ring is used. desirable. In this example, a magnetic fluid is used instead of the piston ring. In this case, a magnetic field for hardening the magnetic fluid is applied from the outside to such an extent that leakage can be prevented.

The effects of the present invention are wide-ranging as follows.
First, for example, when applied to a pressure sensor for measuring the cylinder pressure of a reciprocating cycle engine, the optimum fuel injection amount and its timing can be controlled, thereby reducing hazardous waste and contributing to environmental purification.
In addition, by applying it to the pressure sensor for measuring the cylinder pressure of a reciprocating cycle engine, the optimal fuel injection amount and timing can be controlled, so that combustion efficiency can be improved, global warming prevention and carbon dioxide emission can be suppressed. .
In addition, the reliability of abnormality monitoring and control reliability of nuclear power plants, thermal power plants and the like can be improved.
Further, it is possible to improve the controllability of the power generation device such as a steam turbine, a gas turbine, a rotary engine, a Stirling engine, and the reliability of abnormality monitoring.
In addition, it is possible to improve the reliability of abnormality monitoring and improve the controllability of pressure control in facilities related to production such as chemical plants and steel manufacturing plants.
Moreover, the reliability of abnormality detection can be improved by installing it in the pipeline system in the hydraulic and pneumatic control systems.
In addition, traceability of dynamic pressure measurement standards can be established by developing a new technology called dynamic pressure measurement standards.
In addition, it is possible to easily perform measurement using a pressure sensor and a pressure gauge traceable to the national standard for dynamic pressure.
In addition, the precise dynamic calibration of the micro pressure gauge enables the use of dynamic pressure waveforms in health management such as monitoring of the circulatory system such as the heart, which contributes to improving the health of the people.
In addition, the accuracy of flow rate measurement is improved. For example, the accuracy of pressure measurement in turbulent flow and pulsating flow is improved.
It will also be possible to make international comparisons on dynamic pressure.

It is sectional drawing which shows a 1st Example. It is sectional drawing which shows the other example of a 1st Example. It is sectional drawing which shows a 2nd Example. It is sectional drawing which shows the other example of a 2nd Example. It is sectional drawing which shows a 3rd Example. It is a schematic diagram which shows the whole image of the calibration apparatus of a pressure sensor. It is sectional drawing which shows a 4th Example. It is sectional drawing which shows a 4th Example. It is a block diagram which shows a 1st prior art example. It is a block diagram which shows a 2nd prior art example. It is a block diagram which shows a 3rd prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Weight 2 Piston 3 Cylinder 4 Pressure gauge or pressure sensor 5 Cylinder mounting bracket 6 Motion generator table 7 Accelerometer or acceleration sensor 8 Interferometer laser beam 9 Pressure propagation medium 10 Acceleration sensor 11 Reference pressure sensor 12 Pressure transmission hole 13 Spring mechanism support 14 Spring or spring mechanism 15 Hole 16 Piston base 17 Mirror 18 Corner cube 19 X-axis actuator 20 Y-axis actuator 21 Z-axis actuator 22 X-axis laser interferometer 23 Y-axis laser interferometer 24 Z-axis laser interferometer 25 Signal processor 26 Power amplifier 27 Interface 28 Gas or liquid tank 29 Pressure gauge 30 Pump 31 Piping 32 Valve 33 Amplifier 34 Interferometer 35 Drain 36 Gear 37 Motor 38 Y-axis Actuator Eta

Claims (19)

A pressurizing / depressurizing device that applies a force to compress or expand a gas or a liquid using an inertial force of a weight;
A pressure sensor for measuring the pressure of the gas or liquid is pressurized vacuum before Symbol pressurization device,
A motion generator that applies inertial force to the weight;
And motion generating machine table for placing the pressure sensor and the pressurization device,
A second measuring device for measuring the motion state of the first measuring instrument and the table to measure the motion state of the weight,
A calculation means for deriving the pressure increased or decreased in the pressure increasing / decreasing device from the measured movement state of the weight and the table ,
In motion of the table, by inducing motion of the weight, dynamically changing the pressure to be measured to the pressure sensor,
And pressure data derived from said calculation means, by comparing the signal value or a value derived from the signal value of the pressure sensor, characterized by dynamically calibrate the pressure sensor, the pressure sensor Dynamic calibration device. The pressurization device, the cylinder gas or fluid is filled inside sealed by the piston, the piston N'a Rui has established a weight on one of the cylinders, walk the cylinder of the other of the said piston and fixed to the table, the piston - set up a cylinder based on said motion generator table, given to the front Kitsumu by the motion of said table, sinusoidal vibration, random vibration, or an impulse movement,
The pressure sensor dynamic calibration apparatus according to claim 1, wherein the gas or fluid is pressurized and depressurized using the inertial force generated as a result. The first instrument walking the second instrument is a laser interferometer, said calculation means, said determined Me inertial forces acting on the cylinder inside of the pressure medium, the inertial force of the piston The pressure sensor dynamic calibration apparatus according to claim 2, wherein the pressure to be measured by the pressure sensor is obtained by dividing by an area. The first instrument and the second instrument are each acceleration sensor, obtains the inertial force from the measurement using these acceleration sensors, divided by the inertial force by the area of the piston, said pressure sensor 3. The pressure sensor dynamic calibration apparatus according to claim 2, wherein a pressure to be measured is obtained.   The said acceleration sensor is an acceleration sensor calibrated using the dynamic calibration apparatus of the pressure sensor of Claim 3, The dynamic calibration apparatus of the pressure sensor of Claim 4 characterized by the above-mentioned. The acceleration sensor as a first instrument, the dynamic calibration apparatus of a pressure sensor according to claim 4 or 5, characterized in that it is fixed to the weight. The pressure sensor calibrated by the dynamic calibration device for a pressure sensor according to any one of claims 1 to 6 is used as a reference pressure sensor,
A pressurizing / depressurizing device that compresses or expands a gas or a liquid using the inertial force of the weight;
The pressure of the decompressed the gas or liquid in the pressurization device, with is measured with a pressure sensor to be calibrated and the reference pressure sensor,
A motion generator that gives inertia to the weight;
And a motion generator table to place a pressure sensor to be calibrated the the pressurization device and the reference pressure sensor,
In movement of the table, by inducing motion of the weight, dynamically changing the pressure to be measured and a pressure sensor to be calibrated and the reference pressure sensor,
Dynamic calibration apparatus of a pressure sensor, characterized in that calibrating dynamically pressure sensor to be the calibration by comparison with the reference pressure sensor.   The motion generator includes a vertical actuator and a horizontal actuator, and measures the actual motion of the table in two or three dimensions so that the error between the actual motion of the table and the target value is minimized. 8. The pressure sensor according to claim 1, wherein a signal from an acceleration sensor in the horizontal direction of the table is fed back to a horizontal actuator to control the horizontal movement. Dynamic calibration device. 9. The pressure sensor dynamic calibration apparatus according to claim 4, wherein the acceleration sensor is an acceleration sensor whose sensitivity is defined by a matrix. The motion generating machine, and a vertical actuator and a horizontal actuator, the horizontal actuator, defined its sensitivity in the matrix, the acceleration as the first measurement device provided on the spindle 8. The dynamic calibration apparatus for a pressure sensor according to claim 1, wherein control is performed so as to suppress lateral movement of the table in accordance with a signal from the sensor. Relative movement direction between the piston and the cylinder is vertical line direction, wherein the working point of the overall force applied to the piston unit or the cylinder unit is not fixed to the vibration table to be generated by the relative movement 11. The dynamic calibration device for a pressure sensor according to claim 2, wherein a line connecting the piston portion or the center of gravity of the table portion is on the vertical line. The torque sensor, provided between said table pressurization device, by controlling the movement of the table portion so that the output signal of the torque sensor is small, relative movement between the piston and the cylinder The dynamic calibration device for a pressure sensor according to claim 11, wherein the direction is maintained in a vertical line direction. A strain gauge operating as torque sensor, is provided between the pressurization device and the table, by controlling the movement of the table portion so as distortion detection of the strain gauge is reduced, and the piston and the cylinder The dynamic calibration apparatus for a pressure sensor according to claim 11, wherein the relative motion direction of the pressure sensor is maintained in a vertical line direction. In direction or reverse its inertial force due to the weight of the pressure sensor according to any of claims 1, characterized in that it comprises an arrangement for superimposing biasing force by a restoring force in addition to the inertial force 13 Dynamic calibration device.   The pressure sensor dynamic calibration device according to claim 14, further comprising a configuration for adjusting the bias force by adjusting the restoring force. 16. The pressure sensor dynamic calibration apparatus according to claim 14, wherein the restoring force has a non-linear characteristic. The pressure according to claim 14, wherein the motion generator is driven at a resonance frequency of the movement of the weight in the decompression device or a frequency at which the movement of the weight resonates, and calibration is performed in the resonance state. Sensor dynamic calibration device. A pressurizing and depressurizing device that compresses or expands a gas or liquid pressure medium using the inertial force of the weight;
Wherein is pressurization by the pressurization unit, a pressure sensor for measuring the pressure of said gas or liquid,
A motion generator that applies inertial force to the weight;
And motion generating machine table for placing the pressure sensor and the pressurization device, and a second measuring device for measuring the motion state of the first measuring instrument and the table for measuring the motion state of the weight, these measurements from exercise state, and a calculating means for deriving the pressurization pressure,
In motion of the table, by inducing motion of the weight, by changing the pressure to be measured with the pressure sensor, the pressure data derived from said calculation means, derived from the signal value or the signal value of the pressure sensor In the pressure sensor calibration device, the pressure sensor is calibrated by comparing the measured value with a measured value,
The pressure removal the pressure medium from the pressure reducing device, the frequency characteristic of the pressure sensor was evaluated in a state which does not act on the inertial force of the weight with respect to the pressure medium,
And excisional the pressure medium to the cylinder, is subtracted from the frequency characteristic of the pressure sensor was evaluated in a state in which the action of the inertial force of the weight with respect to the pressure medium,
Dynamic calibration method of a pressure sensor and performs calibration seeking the frequency response characteristic of the pressure Kasensa. Comprising a cylinder and a piston, the pressurization device for compressing or expanding the pressure medium gas or liquid with an inertial force of the weight, which is the pressurization in the previous SL pressurization device to measure the pressure before SL gas or liquid first instrument and the table for measuring a pressure sensor, a motion generating machine which gives an inertial force to the weight, and the motion generating machine table for placing the pressure sensor and the pressurization device, the motion state of the weight a second measuring device for measuring the state of motion from these measured motion state, and a calculating means for deriving the pressurization pressure, exercise of the table, by inducing motion of the weight the varying the pressure to be measured to a pressure sensor, to calibrate the pressure data derived from said calculation means, said pressure sensor by comparing the values derived from the signal value or the signal value of the pressure sensor In the dynamic calibration apparatus of a pressure sensor,
Dynamic calibration method of a pressure sensor and measuring the frequency characteristics of the pressure sensor while relatively rotating with said piston and cylinder.

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