DE102017130979A1 - Measuring device for determining an absolute and / or differential pressure of a medium and a method for operating a measuring device for determining an absolute and / or differential pressure of a medium - Google Patents

Abstract

A measuring device (1) for determining an absolute and / or differential pressure of a medium, the measuring device (1) a pressure measuring cell (2), a measuring and / or evaluation unit (5) and a gyroscope sensor (3) and / or an acceleration sensor (4), wherein the gyroscope sensor (3) and / or the acceleration sensor (4) is provided for detecting measurement data as a function of vibrations on the measuring device (1), wherein the measuring and / or evaluation unit (5) is set up for outputting a measured value of the absolute and / or differential pressure of a medium determined by the pressure measuring cell (2) and for outputting a value with regard to the measurement uncertainty and / or a warning with regard to the measurement uncertainty, wherein for determining the value of the measurement uncertainty and / or Issue of the warning message, the measurement data of the gyroscope sensor (3) and / or the acceleration sensor (4) are taken into account, and a method for operating a measuring device (1) for determining an Abs Olut- and / or differential pressure of a medium.

Description

The present invention relates to a measuring device for determining an absolute and / or differential pressure of a medium according to the preamble of claim 1, and to a method for operating a measuring device for determining an absolute and / or differential pressure of a medium according to the preamble of claim 9.

Measuring devices of process measuring technology with pressure measuring cells can also be referred to as pressure sensors and are known per se. The determination of the pressure by a pressure sensor is subject to certain conditions. Thus, vibrations can be a source of error in the determination of the absolute pressure and / or relative pressure, for example, represent.

In the case of stronger vibrations in the region of the resonance frequency, the sensor can also be damaged. For example, in strong vibrations, air pockets in the transmission medium can be generated.

Based on the aforementioned preliminary considerations, it is now the object of the present invention to provide a measuring device which detects and quantifies occurring vibrations.

The present invention solves the problem by a measuring device with the features of claim 1 and by providing a method with the features of claim 9.

An inventive measuring device is used to determine an absolute and / or differential pressure of a medium. The measuring device comprises a pressure measuring cell, a measuring and / or evaluation unit and a gyroscope sensor and / or an acceleration sensor. Gyroscope sensors and accelerometer are well known in the field of mobile phone technology. The gyroscope sensors and / or acceleration sensors used according to the invention can advantageously be designed as a MEMS sensor. Particularly preferably, both sensors are arranged on a common carrier body and thus formed as a sensor component.

The gyroscope sensor, but in particular the acceleration sensor, is provided for detecting measurement data as a function of vibrations on the measuring device.

The measuring and / or evaluation unit is set up for outputting a measured value of the absolute and / or differential pressure of a medium determined by the pressure sensor and for outputting a value with regard to the measurement uncertainty, the measured data of the gyroscope sensor being used to determine the value of the measurement uncertainty. or the acceleration sensor. For this purpose, the measuring and / or evaluation unit can have a data memory with a computing algorithm, which is executed by means of a computing unit, in particular a microcontroller, also assigned to the measuring and / or evaluation unit.

As an alternative or in addition to a specific value, it is also possible to give a tolerable warning if the value of the measurement uncertainty exceeds a setpoint value. This can be stored analogously on the data memory and be used by the microcontroller for evaluation.

The present measuring device thus makes it possible in a first step to quantify a measurement uncertainty and / or warn of excessive vibrations.

Advantageous embodiments are the subject of the dependent claims.

The measuring and / or evaluation unit can also be equipped to initiate a maintenance service if the value of the measurement uncertainty has exceeded a predetermined desired value. This can be done, for example, by assigning a radio module and by triggering a control command due to a stored on the data storage computer program product by means of which a maintenance service is notified.

Furthermore, the measurement data with regard to the measurement uncertainty by an expanded computer program, which is stored on the data memory of the measuring and evaluation unit, to compensate for the measured value of the absolute and / or differential pressure by the value of the measurement uncertainty.

The measuring and / or evaluation unit can also be set up to check the installation position of the measuring device and / or to compensate the determined measured value with regard to the absolute and / or differential pressure of the medium as a function of the measured data acquired by the gyroscope sensor, in particular for compensation of an installation position ,

Preferably and in a compact design, the gyroscope sensor and the acceleration sensor are part of a common sensor component. Preferably, the sensor component is designed as a MEMS component, in particular with a common carrier element.

The gyroscope sensor and / or the acceleration sensor may preferably be in a common housing with the pressure sensor and the measuring and / or evaluation unit to be arranged.

An inventive method is used to operate a measuring device for determining an absolute and / or differential pressure of a medium. The measuring device has a pressure sensor, a measuring and / or evaluation unit and a gyroscope sensor and / or an acceleration sensor.

1. a) Erfassen von Messdaten in Abhängigkeit von Vibrationen auf das Messgerät durch den Gyroskopen und/oder durch den Beschleunigungssensor;
2. b) Erfassen eines Messwertes, beispielsweise einer Messspannung, zur Ermittlung eines Absolut- und/oder Differenzdruckes eines Mediums durch den Drucksensor;
3. c) Ermittlung eines Wertes hinsichtlich der Messunsicherheit des Messwertes, wobei zur Ermittlung des Wertes der Messunsicherheit die Messdaten des Gyroskop-Sensors und/oder des Beschleunigungssensors berücksichtigt werden.

The method comprises the following steps:

1. a) detecting measurement data as a function of vibrations on the measuring device by the gyroscope and / or by the acceleration sensor;
2. b) detecting a measured value, for example a measuring voltage, for determining an absolute and / or differential pressure of a medium by the pressure sensor;
3. c) determination of a value with regard to the measurement uncertainty of the measured value, the measured data of the gyroscope sensor and / or the acceleration sensor being taken into account for determining the value of the measurement uncertainty.

The measured data of the gyroscope and / or the acceleration sensor and / or values of the measurement uncertainty determined therefrom can advantageously be compared with a setpoint value, a malfunction of the measuring device and / or a misdimensioning of the measuring device being displayed in a process installation if the setpoint is permanently exceeded ,

• 1 schematische Darstellung eines Messgerätes zur Ermittlung eines Absolut- und/oder Differenzdrucks eines Mediums.
• 1 zeigt in stark-vereinfachter Darstellung ein Messgerät 1 zur Ermittlung eines Absolut- und/oder Differenzdruckes eines Mediums.

The invention will be explained in more detail with reference to an embodiment. Individual features of the embodiment can also be realized in other embodiments, not shown.

• 1 schematic representation of a measuring device for determining an absolute and / or differential pressure of a medium.
• 1 shows a highly simplified representation of a measuring device 1 for determining an absolute and / or differential pressure of a medium.

This meter 1 is in this example to a pipeline 10 connected to a process plant.

The measuring device 1 includes a likewise only schematically illustrated pressure measuring cell 2 , The measuring devices and pressure measuring cells for the present application can be designed in many ways. Exemplary for the concrete structure of a measuring device with a diameter cell, the DE 10 2013 114 497 A1 which are referred to in the context of the present invention.

The pressure measuring cell 2 may comprise a membrane, for example a ceramic membrane, and is connected via a measuring line, which may be formed as a capillary, with a pressure transmitter, which is arranged at a process connection.

The diaphragm seal and the capillary are filled with an incompressible transmission medium, usually an oil, for transmitting a process pressure acting on the diaphragm seal to the pressure measuring cell.

By means of the process connection, the diaphragm seal can be arranged in a process environment. Usually this is a tank or a pipeline, whereby a pressure within the tank or the pipeline should be measured as process pressure.

In addition to the pressure measuring cell, the measuring device points 1 an acceleration sensor 4 on. This acceleration sensor 4 Also, accelerometer, may be advantageous as a sensor element with a gyroscope sensor 3 be combined. A corresponding sensor is commercially available, for example, as a BMI160 from Bosch Sensortec. Both the accelerometer and acceleration sensor 4 as well as the gyroscope sensor 3 can be designed as a three-axis sensor.

A gyroscope sensor is known to use earth gravity for position determination.

The measuring accuracy of the measuring device 1 Among other things, the pressure measuring cell may depend on the installation position of the pressure measuring cell in a process plant with respect to earth gravity. Therefore, the meter needs 1 a position correction depending on the installation position.

A gyroscope sensor can in particular also the installation position of the measuring device 1 because it is based on earth gravity. This can be a position correction of the meter 1 through the gyroscope sensor 3 take place, for example, directly after the installation of the measuring device in a process plant.

An accelerometer or accelerometer determines measurements based on vibration. Crystals, analogous to the piezoelectric effect, can generate a voltage under load, whereby the load is caused by vibrations.

Experienced the meter 1 too much vibration, this can lead to unnoticed measurement inaccuracies or to unnoticed destruction of the device. By using an acceleration sensor, on the one hand, a correction of the measured value can be made for compensation. On the other hand, monitoring the excessive vibration load of the meter 1 take place in order to prevent damage to the measuring device at an early stage 1 to detect and warn against it.

The measuring device has a measuring and / or evaluation unit for evaluating the measured data of the individual sensors 5 on. This can have a data memory and a microcontroller for storing and executing computer program products with corresponding calculation algorithms.

Typically, today a compact sensor is realized and commercially available, which combines an acceleration sensor with a gyroscope sensor. This can be done with a single sensor component 7 in a compact design, both the mounting position and vibrations that are on the meter 1 act, be determined.

The sensor component 7 is advantageous and protected against environmental influences in a housing 6 of the meter 1 arranged.

The automatic correction of the measured values preferably takes place as a function of the installation position and / or the vibrations determined.

Further, upon the occurrence of vibration beyond the specification of the meter automatically a service message may be triggered, e.g. Warning of reduced measurement accuracy and / or premature wear.

A combination of a three-axis gyroscopic sensor and acceleration sensor thus enables the automatic detection and correction of position-dependent artifacts of the measuring device connected to a process installation in an installed position and / or an output of a warning or operating instruction to the user.

In addition, warnings regarding excessive vibration can be triggered and thus provide the user with information on reduced measurement inaccuracy and / or increased wear as an indication of preventive maintenance. It is also possible that the measuring and / or evaluation unit automatically triggers such maintenance. For this purpose, the measuring and / or evaluation unit preferably has an additional communication component, e.g. a radio module that can communicate with a maintenance service.

LIST OF REFERENCE NUMBERS

1

gauge

2

pressure sensor

3

Gyroscope sensor

4

accelerometer

5

Measuring and evaluation unit

6

casing

7

sensor component

10

pipeline

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102013114497 A1 [0022]

Claims (10)

Measuring device (1) for determining an absolute and / or differential pressure of a medium, wherein the measuring device (1) a pressure measuring cell (2), a measuring and / or evaluation unit (5) and a gyroscope sensor (3) and / or a Acceleration sensor (4), wherein the gyroscope sensor (3) and / or the acceleration sensor (4) is provided for detecting measurement data as a function of vibrations on the measuring device (1), characterized in that the measuring and / or evaluation unit ( 5) is set up for outputting a measured value of the absolute and / or differential pressure of a medium determined by the pressure measuring cell (2) and for outputting a value with regard to the measurement uncertainty and / or a warning message with regard to the measurement uncertainty, whereby the value of the measurement uncertainty and / or or the measurement data of the gyroscope sensor (3) and / or the acceleration sensor (4) are taken into account for issuing the warning message. Meter after Claim 1 , characterized in that the measuring and / or evaluation unit (5) is also equipped to initiate a maintenance service if the value of the measurement uncertainty has exceeded a predetermined desired value. Meter after Claim 1 or 2 , characterized in that the measured value of the absolute and / or differential pressure is compensated by the value of the measurement uncertainty. Measuring device according to one of the preceding claims, characterized in that the pressure measuring cell (2) comprises a membrane and that the pressure measuring cell (2) is connected by means of a capillary with a pressure transmitter, wherein the capillary is filled with an incompressible transmission medium for transmitting a medium pressure of the Diaphragm seal on diaphragm of pressure cell (2). Measuring device according to one of the preceding claims, characterized in that the measuring and / or evaluation unit (5) is designed to control the installation position of the measuring device (1). Measuring device according to one of the preceding claims, characterized in that the measuring and / or evaluation unit (5) is arranged to compensate the determined measured value with respect to the absolute and / or differential pressure of the medium in dependence on the gyroscope sensor (3) detected Measured data. Measuring device according to one of the preceding claims, characterized in that the gyroscope sensor (3) with the acceleration sensor (4) is part of a common sensor component (7), in particular with a common carrier element. Measuring device according to one of the preceding claims, characterized in that the gyroscope sensor (3) and / or the acceleration sensor (4) in a common housing (6) with the pressure measuring cell (2) and the measuring and / or evaluation unit (5) is arranged. Method for operating a measuring device (1) for determining an absolute and / or differential pressure of a medium, wherein the measuring device (1) comprises a pressure measuring cell (2), a measuring and / or evaluation unit (5) and a gyroscope sensor (3) and / or an acceleration sensor (4), the method being characterized by the following steps: a) detecting measurement data as a function of vibrations on the measuring device (1) by the gyroscope sensor (3) and / or by the acceleration sensor (4); b) detecting a measured value for determining an absolute and / or differential pressure of a medium by the pressure measuring cell (2); c) determination of a value with regard to the measurement uncertainty of the measured value, wherein the measured data of the gyroscope sensor (3) and / or the acceleration sensor (4) are taken into account for determining the value of the measurement uncertainty. Method according to Claim 9 , characterized in that the measurement data of the gyroscope sensor (3) and / or the acceleration sensor (4) and / or values of the measurement uncertainty determined therefrom is compared with a desired value, wherein a malfunction of the measuring device (1) is permanently exceeded when the nominal value is exceeded. and / or a misdimensioning of the measuring device (1) is displayed when used in a process plant.

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