Coriolis measuring sensor and coriolis measuring device

Abstract

The present invention relates to a Coriolis measuring sensor (10) for measuring the density or mass flow rate of a medium flowing through a pipe in a Coriolis measuring device (1), comprising: at least one measuring tube (11) for conducting the medium; a support (12) for supporting the at least one measuring tube; at least one vibration generator (13) for generating vibration of the measuring tube; at least two vibration sensors (14) for sensing the vibration of the measuring tube, wherein each vibration sensor has at least one permanent magnet (14.1) and at least one sensor coil (14.2), and wherein the vibration generator has at least one permanent magnet (13.1) and at least one exciter coil (13.2) in each case, characterized in that: the Coriolis measuring sensor has at least one amplitude sensor (15) designed to sense the vibration amplitude of the measuring tube vibration.

Description

Technical Field

[0001] The present invention relates to a Coriolis measuring sensor for measuring the density or mass flow rate of a medium flowing through a pipe, and to a Coriolis measuring device having such a Coriolis measuring sensor. Background Technology

[0002] Such Coriolis measuring sensors or devices are well known in the art, as shown in DE102015120087A1, and typically include one or more measuring tubes connected to a pipe during operation and guiding the flow of a medium through the pipe. A vibration generator causes the measuring tubes to vibrate, and a vibration sensor senses the vibration of the measuring tubes. By utilizing the Coriolis effect, conclusions about the properties of the medium, such as density or mass flow rate, can be drawn from the vibration of the measuring tubes.

[0003] Vibration generators and vibration sensors typically include at least one permanent magnet and at least one coil in each case, wherein vibration of the measuring tube causes movement of the permanent magnet relative to the associated coil. In the case of the generator, vibration of the measuring tube is triggered by applying an exciter current to the exciter coil, wherein the resulting magnetic field triggers a force on the associated permanent magnet. Conversely, vibration of the measuring tube results in the induction of a voltage, which is evaluated as the measured voltage.

[0004] The interaction between the permanent magnet and the associated coil is strongly influenced by the state of the permanent magnet. Aging effects cause the inherent magnetic field of the permanent magnet to decay. If these effects are not considered or understood, measurements of the dielectric properties will be distorted. Summary of the Invention

[0005] Therefore, the object of the present invention is to provide a Coriolis measurement sensor and a Coriolis measurement device, wherein the aging effect of permanent magnets can be identified and compensated.

[0006] The objective is achieved by the Coriolis measuring sensor and Coriolis measuring device according to the present invention.

[0007] The Coriolis measuring sensor in the Coriolis measuring device of the present invention for measuring the density or mass flow rate of a medium flowing through a pipe includes:

[0008] At least one measuring tube is used to conduct the medium;

[0009] A support body for supporting at least one measuring tube;

[0010] At least one vibration generator is used to generate vibration of the measuring tube;

[0011] At least two vibration sensors are used to sense the vibration of the measuring tube.

[0012] In each case, the vibration sensor has at least one permanent magnet and at least one sensor coil.

[0013] Furthermore, the vibration generator in each case has at least one permanent magnet and at least one exciter coil.

[0014] in

[0015] The Coriolis measurement sensor has at least one amplitude sensor, which is designed to sense the vibration amplitude of the measuring tube.

[0016] The amplitude sensor has a first coil and a second coil, which are magnetically coupled to each other, and specifically, are coaxially aligned.

[0017] The coils are configured to move relative to each other via the vibration of the measuring tube, specifically relative to each other along their coil axes.

[0018] The first coil is designed to measure current, specifically direct current, and to generate a magnetic field.

[0019] The second coil is configured to sense the magnetic field and generate an induced measurement voltage.

[0020] In this way, the amplitude of the measuring tube can be measured without the presence of easily aging permanent magnets, thereby enabling the vibration sensor and / or vibration generator to be calibrated during operation, or to compensate for aging-related damage to the vibration sensor or vibration generator during operation.

[0021] Direct current or alternating current can be applied to the first coil, wherein the frequency of such alternating current should not match the vibration frequency or harmonics of the measuring tube, thereby preventing undesirable effects, especially mutual interference.

[0022] Applying alternating current to the first coil, particularly at a frequency greater than the oscillation frequency of the measuring tube, can have advantages in signal processing. However, an alternating electromagnetic field may not be desirable due to radiation. Those skilled in the art can consider these aspects according to their specific circumstances and thus apply the measuring current to the first coil.

[0023] In one embodiment, the first coil has a fixed position relative to the support, and the second coil is configured to follow the vibrational movement of the measuring tube.

[0024] In this way, non-static magnetic field components can be prevented from being generated by the coil supplied with the measuring current due to its own movement.

[0025] In one embodiment, the amplitude sensor is configured to sense the vibration amplitude of the measuring tube in the region of maximum amplitude.

[0026] In one embodiment, the first coil is a Helmholtz coil, wherein the second coil is designed to move at least partially into the first coil by means of vibration of the measuring tube.

[0027] In one embodiment, the vibration amplitude of the measuring tube can be calculated by measuring the current and inducing the measuring voltage.

[0028] The induced voltage in the second coil provides a conclusion about the velocity of the measuring tube, and the measuring current is a measure of the magnetic field strength generated in the first coil. The vibration amplitude can be calculated using other variables, such as the inductance of the coil.

[0029] In one embodiment, the Coriolis measurement sensor has at least one pair of measuring tubes, wherein the measuring tubes in the pair are configured to vibrate relative to each other, wherein the vibration generator has two exciter coils, each exciter coil being arranged on one measuring tube of the pair, and wherein a permanent magnet of the vibration generator is arranged on one measuring tube.

[0030] and / or one of them

[0031] The vibration sensor has two sensor coils, which are arranged on one measuring tube of a measuring tube pair in each case. The permanent magnet of the vibration generator is arranged on one measuring tube. The exciter coil and / or sensor coil of each vibration sensor form the first and second coils of the amplitude sensor in each case.

[0032] The Coriolis measuring device according to the present invention for measuring the density or mass flow rate of a medium flowing through a pipe includes:

[0033] According to the Coriolis measurement sensor of the present invention,

[0034] The electronic measurement / operation circuit is configured to operate the vibration generator and amplitude sensor, and is also configured to provide measurements of density and / or mass flow rate based on the vibration of the measuring tube sensed by the vibration sensor.

[0035] Electronic enclosure, in which electronic measurement / operation circuitry is arranged.

[0036] In this circuit, via an amplitude sensor and at least one vibration sensor, the electronic measurement / operation circuit is configured to determine, and in particular, compensate for, the aging of the permanent magnet of the vibration sensor.

[0037] and / or

[0038] The aging of the permanent magnet in the vibration generator is determined, and in particular, compensated, by using an amplitude sensor and at least one vibration generator.

[0039] In one embodiment, the electronic measurement / operation circuit is configured to determine the vibration amplitude of the measuring tube by measuring the current and measuring the voltage.

[0040] In one embodiment, the electronic measurement / operation circuit is configured to compensate for the aging of the permanent magnet of the vibration sensor by at least the following measurement variables:

[0041] The amplitude of vibration measured in the tube during calibration;

[0042] The induced voltage in the sensor coil during calibration;

[0043] The measured vibration amplitude of the measuring tube at the current time point;

[0044] The induced voltage in the sensor coil at the current time point

[0045] and / or one of them

[0046] The electronic measurement / operation circuit is configured to compensate for the aging of the permanent magnets in the vibration generator by measuring at least the following variables:

[0047] The amplitude of vibration measured in the tube during calibration;

[0048] The induced voltage in the exciter coil during calibration;

[0049] The measured vibration amplitude of the measuring tube at the current time point;

[0050] The induced voltage in the exciter coil at the current time point.

[0051] In a method for compensating for aging of the vibration generator / vibration sensor of the Coriolis measuring device according to the invention, at least one amplitude sensor determines the vibration amplitude of at least one measuring tube, wherein the amplitude sensor has a first coil and a second coil, which are magnetically coupled to each other, particularly coaxially aligned, wherein the coils are designed to move relative to each other by vibration of the measuring tube, particularly relative to each other along their coil axes.

[0052] The first coil is configured to measure current, particularly direct current, and generate a magnetic field, while the second coil is configured to sense the magnetic field and generate an induced measurement voltage.

[0053] The method includes the following steps:

[0054] The vibration amplitude of the measuring tube during calibration is measured by using an amplitude sensor, which measures both current and voltage.

[0055] The induced voltage in the exciter coil / sensor coil is measured during calibration;

[0056] The vibration amplitude of the measuring tube at the current point in time is measured by measuring current and voltage, using an amplitude sensor.

[0057] Measure the induced voltage in the exciter coil / sensor coil at the current time point;

[0058] The aging state of the permanent magnet of the vibration generator / vibration sensor can be determined at least by measuring variables sensed during the aforementioned method steps. Attached Figure Description

[0059] The present invention will now be described with reference to exemplary embodiments shown in the accompanying drawings. As follows:

[0060] Figure 1 This is an exemplary Coriolis measuring device according to the present invention;

[0061] Figure 2a This is a schematic diagram of an exemplary embodiment of the arrangement of vibration sensors on two measuring tubes or a vibration generator;

[0062] Figure 2b ( ) is a schematic diagram of an exemplary embodiment of the arrangement of amplitude sensors on two measuring tubes. Detailed Implementation

[0063] Figure 1 The diagram illustrates the structure of an exemplary Coriolis measuring device 10 according to the invention, equipped with an exemplary Coriolis measuring sensor. The Coriolis measuring sensor has a vibration system with two measuring tubes 11, each measuring tube having an inlet and an outlet, a support 12 for supporting the measuring tube, a vibration generator 13, two vibration sensors 14, and an amplitude sensor 15. The generator is designed to excite the two measuring tubes to vibrate perpendicularly to the longitudinal plane of the measuring tubes defined by the arched measuring tubes in each case. The sensors are designed to sense the vibrations applied to the measuring tubes. A temperature sensor 17 is configured to sense the temperature of the support, the measuring tubes (affected by the medium temperature), and the support. Such a temperature sensor may also be provided with the sensors and generator. The Coriolis measuring sensor is connected to an electronic housing 80 of the Coriolis measuring device, which is designed to house an electronic measurement / operation circuit 77. The electronic measurement / operation circuit 77 is designed to operate the vibration generator, the vibration sensors, and the amplitude sensor 15, and to determine and provide flow rate and / or density measurements based on the vibration characteristics of the measuring tubes measured by the sensors. The generator and sensor elements are connected to the electronic measurement / operation circuit via electrical connection 19. In each case, electrical connection 19 can be combined together via a cable.

[0064] Several influences must be considered when operating such a Coriolis measuring device. The generator efficiency thus affects the vibration amplitude of the measuring tube, and the sensor sensitivity affects the ability to convert the vibration of the measuring tube into a measured variable, such as voltage or current. Coriolis measuring devices are typically calibrated under standard conditions before startup, for example, by a customer of the Coriolis measuring device manufacturer, and, among other things, the relationship between the generator's excitation of the measuring tube vibration and the sensor's detection of the vibration is recorded. The generator efficiency and sensor sensitivity are thus affected, which can lead to both reversible and irreversible changes in these variables.

[0065] An example of a reversible effect is the increase in the ohmic resistance of the sensor's coil assembly due to a rise in temperature, which results in a reduced voltage induced by moving the sensor magnet relative to the coil assembly. An example of an irreversible change is the aging of the sensor magnet, such as due to overheating.

[0066] An amplitude sensor 15 having a first coil 15.1 and a second coil 15.2 (see Figure 2) is configured to measure the vibration amplitude of the measuring tube, wherein the first coil is configured to withstand a measuring current, particularly direct current, and generate a magnetic field, and wherein the second coil is configured to sense the magnetic field and generate an induced measuring voltage.

[0067] By arranging the coils in this way so that the coils move relative to each other due to the vibration of the measuring tube, the vibration amplitude can be calculated by measuring the current and voltage as well as the vibration frequency of the measuring tube.

[0068] In the Coriolis measuring apparatus shown in this paper, the first coil and the second coil can be arranged on the measuring tube so that they are aligned with each other, in particular coaxially aligned, thereby achieving good magnetic coupling, and moving relative to each other by vibration of the measuring tube, in particular moving relative to each other along their coil axes 15.3.

[0069] Alternatively, one coil may be attached to the measuring tube and the other coil fixed to the support, wherein, in this case, they are similarly aligned with each other, in particular coaxially aligned, and due to the vibration of the measuring tube, they move relative to each other, in particular relative to each other along their coil axes 15.3.

[0070] The electronic measurement / operation circuit 77 is configured to compensate for the aging of the permanent magnet 14.1 of the vibration sensor by at least the following measurement variables:

[0071] The amplitude of vibration measured in the tube during calibration;

[0072] The induced voltage in the sensor coil during calibration;

[0073] The measured vibration amplitude of the measuring tube at the current time point;

[0074] The induced voltage in the sensor coil at the current time point

[0075] and / or one of them

[0076] The electronic measurement / operation circuit 77 is configured to compensate for the aging of the permanent magnet 13.1 of the vibration generator 13 by measuring at least the following variables:

[0077] The amplitude of the measured vibration in tube 11 was measured during calibration.

[0078] The induced voltage in the exciter coil during calibration;

[0079] The measured vibration amplitude of the measuring tube at the current time point;

[0080] The induced voltage in the exciter coil at the current time point.

[0081] In this way, the amplitude of the measuring tube can be measured without the presence of easily aging permanent magnets, thereby enabling the vibration sensor and / or vibration generator to be calibrated during operation, or to compensate for aging-related damage to the vibration sensor or vibration generator during operation.

[0082] Direct current or alternating current can be applied to the first coil, wherein the frequency of such alternating current should not match the vibration frequency or harmonics of the measuring tube, thereby preventing undesirable effects, especially mutual interference.

[0083] Applying alternating current to the first coil, particularly at a frequency greater than the oscillation frequency of the measuring tube, can have advantages in signal processing. However, an alternating electromagnetic field may not be desirable due to radiation. Those skilled in the art can consider these aspects according to their specific circumstances and thus apply the measuring current to the first coil.

[0084] The Coriolis measuring device according to the invention is not limited to having two measuring tubes. Therefore, the invention can be implemented in Coriolis measuring devices with any number of measuring tubes, for example, even in single-tube or four-tube measuring devices.

[0085] Unlike the case shown in this article, the measuring tube can also be a straight tube, for example, configured to perform lateral or torsional vibrations.

[0086] Figure 2aThe diagram illustrates an exemplary schematic arrangement of a vibration generator 13 or a vibration sensor 14 on two measuring tubes of a Coriolis measuring sensor, wherein permanent magnets 13.1, 14.1 are arranged on one measuring tube, and in each case, a sensor coil 14.2 or an exciter coil 13.2 is arranged on the other measuring tube. The measuring tubes are configured to vibrate relative to each other, wherein, in the case of the vibration sensor, a voltage is induced in the coil due to the relative motion between the permanent magnet and the sensor coil, which can be used as a measuring voltage to determine the properties of the medium. In the case of the vibration generator, a current can be applied to the exciter coil to apply a force to the respective permanent magnet, thereby generating vibration of the measuring tube. Among other things, the efficiency of generating vibration of the measuring tube or its detection by induction of voltage in the sensor coil depends on the aging condition of the permanent magnets.

[0087] In order to sense these aging conditions, the amplitude sensor according to the invention is configured with a first coil 15.1 and a second coil 15.2 (see...). Figure 2b As shown in the figure, in each case, a coil can be arranged on the measuring tube. A magnetic field is generated by applying a measuring current, particularly direct current, to the first coil, and the vibration amplitude of the measuring tube can be determined by sensing the magnetic field using a second coil.

[0088] To compensate for the aging effect in vibration sensors, the following measurement variables can be considered:

[0089] The amplitude of vibration measured in the tube during calibration;

[0090] The induced voltage in the sensor coil during calibration;

[0091] The measured vibration amplitude of the measuring tube at the current time point;

[0092] The induced voltage in the sensor coil at the current time point.

[0093] To compensate for the aging effect in the vibration generator, the following measurement variables can be considered:

[0094] The amplitude of vibration measured in the tube during calibration;

[0095] The induced voltage in the exciter coil during calibration;

[0096] The measured vibration amplitude of the measuring tube at the current time point;

[0097] The induced voltage in the exciter coil at the current time point.

[0098] To derive the vibration amplitude at the location of the amplitude sensor from the vibration amplitude at the location of the vibration generator or vibration sensor, other measurement variables can be considered for compensation, such as medium pressure, medium temperature, medium density, and the stiffness of the measuring tube.

[0099] List of reference numerals

[0100] 1 Coriolis measuring device

[0101] 10 Coriolis Measurement Sensors

[0102] 11 Measuring tube

[0103] 12 Support

[0104] 13 Vibration Generator

[0105] 13.1 Permanent magnets

[0106] 13.2 Exciter Coil

[0107] 14 Vibration Sensor

[0108] 14.1 Permanent magnets

[0109] 14.2 Sensor Coil

[0110] 15 Amplitude Sensor

[0111] 15.1 First Coil

[0112] 15.2 Second Coil

[0113] 15.3 Coil Shaft

[0114] 77 Electronic Measurement / Operating Circuit

[0115] 80 Electronic casing

Claims

1. A Coriolis measuring sensor (10) for a Coriolis measuring device (1), the Coriolis measuring device (1) being used to measure the density or mass flow rate of a medium flowing through a pipe, comprising: At least one measuring tube (11) is provided for conducting the medium; A support (12) for supporting the at least one measuring tube; At least one vibration generator (13) is used to generate vibration of the measuring tube; At least two vibration sensors (14) are used to sense the vibration of the measuring tube. Each of the vibration sensors has at least one permanent magnet (14.1) and at least one sensor coil (14.2). Furthermore, the vibration generator in each case has at least one permanent magnet (13.1) and at least one exciter coil (13.2) in each case. in The Coriolis measuring sensor has at least one amplitude sensor (15) configured to sense the vibration amplitude of the measuring tube. The characteristic feature is that the amplitude sensor has a first coil (15.1) and a second coil (15.2), which are magnetically coupled to each other. The coils are designed to move relative to each other via the vibration of the measuring tube. The first coil is designed to be supplied with a measuring current and to generate a magnetic field. The second coil is configured to sense the magnetic field and generate an induced measurement voltage.

2. The Coriolis measurement sensor according to claim 1, in, The first coil (15.1) and the second coil (15.2) are coaxially aligned with each other.

3. The Coriolis measurement sensor according to claim 1, in, The coils are designed to move relative to each other along their coil axes (15.3).

4. The Coriolis measurement sensor according to claim 1, in, The first coil is designed to be supplied with direct current.

5. The Coriolis measuring sensor according to claim 1, in, The first coil (15.1) has a fixed position relative to the support (12), and the second coil (15.2) is designed to follow the vibration of the measuring tube (11).

6. The Coriolis measuring sensor according to claim 1, in, The amplitude sensor (15) is configured to sense the vibration amplitude of the measuring tube in the region of maximum amplitude.

7. The Coriolis measuring sensor according to any one of claims 1-6, in, The first coil (15.1) is a Helmholtz coil, wherein the second coil (15.2) is designed to move at least partially into the first coil by vibration of the measuring tube.

8. The Coriolis measuring sensor according to any one of claims 1-6, in, The vibration amplitude of the measuring tube (11) can be calculated using the measuring current and the induced measuring voltage.

9. The Coriolis measuring sensor according to any one of claims 1-6, in, The Coriolis measuring sensor has at least one pair of measuring tubes, wherein the measuring tubes in the pair are configured to vibrate relative to each other. The vibration generator (13) has two exciter coils (13.2), each exciter coil being arranged on one measuring tube of the measuring tube pair, wherein the permanent magnet of the vibration generator is arranged on one measuring tube. and / or one of them The vibration sensor (14) has two sensor coils (14.2) in each case, the sensor coils being arranged on one measuring tube of the measuring tube pair, wherein the permanent magnet of the vibration generator is arranged on one measuring tube. In each case, the exciter coil and / or sensor coil of each vibration sensor form the first coil (15.1) and the second coil (15.2) of the amplitude sensor.

10. A Coriolis measuring device (1) for measuring the density or mass flow rate of a medium flowing through a pipe, comprising: Coriolis measuring sensor (10) according to any one of claims 1-9; An electronic measurement / operation circuit (77) is configured to operate a vibration generator (13) and an amplitude sensor (15), and is also configured to provide measurements of density and / or mass flow rate based on vibrations of the measuring tube sensed by the vibration sensor. Electronic housing (80), in which the electronic measurement / operation circuit is arranged. Its features are: The electronic measurement / operation circuit is configured to determine and compensate for aging of the permanent magnet (14.1) of the vibration sensor via the amplitude sensor (15) and at least one vibration sensor (14). and / or The aging of the permanent magnet (13.1) of the vibration generator is determined and compensated by the amplitude sensor (15) and at least one vibration generator (13).

11. The Coriolis measuring device according to claim 10, in, The electronic measurement / operation circuit (77) is configured to determine the vibration amplitude of the measuring tube (11) by means of the measuring current and the measuring voltage.

12. The Coriolis measuring device according to claim 10, in, The electronic measurement / operation circuit (77) is configured to compensate for the aging of the permanent magnet (14.1) of the vibration sensor by at least the following measurement variables: The measured vibration amplitude of the measuring tube during calibration; The induced voltage in the sensor coil during calibration; The measured vibration amplitude of the measuring tube at the current time point; The induced voltage in the sensor coil at the current time point and / or one of them The electronic measurement / operation circuit (77) is configured to compensate for the aging of the permanent magnet (13.1) of the vibration generator (13) by at least the following measurement variables: The measured vibration amplitude of the measuring tube (11) during calibration; The induced voltage in the exciter coil during calibration; The measured vibration amplitude of the measuring tube at the current time point; The induced voltage in the exciter coil at the current time point.

13. A method for compensating for aging of the vibration generator / vibration sensor in a Coriolis measuring device according to any one of claims 10-12, in, At least one amplitude sensor determines the vibration amplitude of at least one measuring tube, wherein the amplitude sensor has a first coil (15.1) and a second coil (15.2) magnetically coupled to each other, wherein the coils are designed to move relative to each other through the vibration of the measuring tube. The first coil is configured to be supplied with a measuring current and generate a magnetic field, while the second coil is configured to sense the magnetic field and generate an induced measuring voltage. The method includes the following steps: The vibration amplitude of the measuring tube during calibration is measured using the measuring current and the measuring voltage, with the aid of an amplitude sensor. The induced voltage in the exciter coil / sensor coil during measurement calibration; The vibration amplitude of the measuring tube at the current time point is measured using the measuring current and the measuring voltage, with the aid of an amplitude sensor. Measure the induced voltage in the exciter coil / sensor coil at the current time point; The aging state of the permanent magnet of the vibration generator / vibration sensor can be determined at least by measuring variables sensed during the aforementioned method steps.

14. The method according to claim 13, in, The first coil (15.1) and the second coil (15.2) are coaxially aligned with each other.

15. The method according to claim 13, in, The coils are designed to move relative to each other along their coil axes (15.3).

16. The method according to claim 13, in, The first coil is configured to be supplied with direct current.

Images