Sensor and measurement system formed therewith

Abstract

The invention relates to a sensor comprising a deformation body (111) that is flat at least in some portions and that has a planar surface (111+) and an opposite planar surface (111#), a sensor vane (112) extending starting from the first surface (111+) of the deformation body, a connection sleeve (113) extending starting from the deformation body, a converter element (12) which is arranged within the connection sleeve (113) and contacts the surface (111+) of the deformation body with a contact face for generating an electric sensor signal representing movements of the sensor vane that change over time and / or deformations of the deformation body that change over time, and also comprising fastening means which are positioned within the connection sleeve (113) and are mechanically connected thereto for fixing the converter element (12) in the connection sleeve (112). The connection sleeve has an internal thread in a distal end remote from the deformation body (111), and the fastening means (13) comprise an (inner) threaded sleeve (132) having an external thread, and a cylindrical add-on element (133). In addition, the threaded sleeve (132) is screwed into the internal thread, and the add-on element (133) is positioned between the (inner) threaded sleeve and the converter element, in such a way that an abutment for the add-on element is formed by means of the threaded sleeve, and at least the add-on element is elastically deformed by exerting a pressing force which holds the converter element pressed against the deformation body or is elastically deformed by forming at least a frictional connection connecting a converter element and the deformation body to each other.

Description

[0001] Sensor and measuring system formed with it

[0002] The invention relates to a sensor formed, in particular a sensor for detecting pressure fluctuations in a flowing fluid, or a measuring system formed thereby.

[0003] In process measurement and automation technology, measuring systems designed as vortex flow meters are often used to measure flow velocities of fluids flowing in pipelines, in particular fast-flowing and / or hot gases and / or fluid flows with a high Reynolds number (Re), or of volume or mass flows corresponding to a respective flow velocity (u). Examples of such measuring systems are known from US-A 2006 / 0230841, US-A 2008 / 0072686, US-A 2011 / 0154913, US-A 2011 / 0247430, US-A 2016 / 0123783, US-A 2017 / 0284841, US-A 2019 / 0094054, US-A 60 03 384, US-A 61 01 885, US-B 63 52 000, US-B 69 10 387 or US-B 69 38 496 and are also offered by the applicant itself, for example under the product name “PROWIRL D 200”, “PROWIRL F 200”, “PROWIRL O 200”, “PROWIRL R 200” (http: / / www.de.endress.eom / #products / prowirl).

[0004] The measuring systems shown each have a bluff body which projects into the lumen of the respective pipeline, for example, as a system component of a heat supply network or a turbine circuit, or into a lumen of a measuring tube inserted in the course of the same pipeline, and against which the fluid flows, for generating vortices arranged in a so-called Kärmän vortex street within the partial volume of the fluid flow flowing immediately downstream of the bluff body. As is known, the vortices are generated at the bluff body with a separation rate (1 / fvtx) that is dependent on the flow velocity. Furthermore, the measuring systems have a bluff body integrated into orconnected to it or downstream of it, namely in the area of ​​the Kärmän vortex street in the flow, thus in the lumen of the protruding sensor, which serves to record pressure fluctuations in the Kärmän vortex street formed in the flowing fluid and to convert them into a sensor signal representing the pressure fluctuations, namely to deliver a - for example electrical or optical - signal that corresponds to a pressure prevailing within the fluid, which is subject to periodic fluctuations as a result of counter-rotating vortices downstream of the bluff body or that has a signal frequency (~ fvtx) corresponding to the shedding rate of the vortices.For this purpose, the sensor has a deformation body and a sensor vane - usually rod-shaped, plate-shaped, or wedge-shaped - extending from a substantially planar surface of the deformation body, and is designed to detect pressure fluctuations in the Kärmän vortex street, namely to convert them into movements of the deformation body corresponding to the pressure fluctuations. The deformation body has a - usually circular - outer edge segment which is designed to be hermetically sealed, for example materially bonded, to a holder serving to hold the deformation body to a wall of a tube, such that the deformation body covers or hermetically seals an opening provided in the wall of the tube and that the surface of the deformation body carrying the sensor vane is exposed to the fluid-conducting lumen of the measuring tube orfacing the pipeline, thus the sensor vane protrudes into the same lumen. The deformation body is typically designed as a thin membrane and shaped such that at least a membrane thickness, measured as a minimum thickness of an inner membrane segment defined by the aforementioned outer edge segment, is much smaller than a membrane diameter, measured as a largest diameter of an area defined by the outer edge segment.In order to achieve the highest possible measurement sensitivity, namely the highest possible sensitivity of the sensor to the pressure fluctuations to be recorded and at the same time the highest possible mechanical natural frequency, namely above the highest detachment rate to be measured, for the bending vibration mode of the deformation body with the sensor vane forced by the pressure fluctuations, such deformation bodies of established measuring systems typically have a diameter-to-thickness ratio that is approximately in the order of 20:1. As described, among others, in the aforementioned US-A 2016 / 0123783, US-A 2017 / 0284841, US-A 2019 / 0094054, andAs shown in US-B 63 52 000, sensors of the type in question can occasionally also have a compensating body which extends from a surface of the deformation body facing away from the surface carrying the sensor flag and is usually designed in the form of a rod, plate or sleeve, and which serves in particular to compensate for forces or moments resulting from movements of the sensor assembly, for example as a result of vibrations in the pipeline, or to avoid undesired movements of the sensor flag resulting therefrom.

[0005] For the purpose of generating the sensor signal, each of the sensors further comprises a (mechanical-to-electrical) transducer element, which is typically designed to detect movements of the deformable body and convert them into an electrical sensor signal. In the sensors known from US-A 2017 / 0284841, US-A 2019 / 0094054 and US-B 63 52 000, the transducer element is formed by a piezoceramic, for example in the form of a piezo disc. The sensor is further connected, on a side facing away from the fluid-carrying lumen, to a transducer electronics unit - typically encapsulated in a pressure- and impact-resistant manner, possibly also hermetically sealed to the outside. Transducer electronics of industrial measuring systems usually have a corresponding transducer element connected to the transducer element via connecting cables, possiblywith the interposition of electrical barriers and / or galvanic isolation points, an electrically connected digital measuring circuit for processing the at least one sensor signal generated by the transducer element and for generating digital measured values ​​for the respective measured variable to be recorded, namely the flow velocity, the volume flow and / or the mass flow. The converter electronics of industrially suitable measuring systems or those established in industrial measurement technology, which are usually housed in a protective housing made of metal and / or impact-resistant plastic, also usually provide external interfaces that conform to an industry standard, for example DIN IEC 60381-1, for communication with higher-level measuring and / or control systems, for example those formed by programmable logic controllers (PLCs).Such an external interface can, for example, be designed as a two-wire connection that can be integrated into a current loop and / or be compatible with established industrial fieldbuses.

[0006] Not least due to the relatively high diameter-to-thickness ratio of the deformation body required by the measuring principle, conventional sensors of the type in question - even when using a high-strength nickel-based alloy such as Inconel 718 (Special Metals Corp.) as the material - usually have a compressive strength, namely a maximum permissible operating pressure, above which irreversible plastic deformation of the sensor or even bursting of the deformation body is to be expected, which may be too low for the extremely high pressures or pressure surges that actually occur in certain applications.Such sensors exhibit a dependence of pressure resistance on the operating temperature (pressure-temperature curve) which is too unfavourable for such applications, such that, for example, in actually predestined hot steam applications with steam temperatures of over 200°C, non-destructive resistance can no longer be guaranteed for operating pressures above 100 bar which occasionally occur, for example as a result of so-called condensation-induced water hammers (CIWH).

[0007] To improve the pressure resistance of the sensor, US-A 2016 / 0123783, for example, shows a support device for the deformation body arranged on the transducer element side, thus not contacted by the fluid to be measured during operation, against which the deformation body is partially applied at a static pressure exceeding a predetermined limit, for example, more than 40 bar, such that mechanical stresses established therein can be kept below a specified maximum permissible stress even at higher pressures of up to 250 bar. A disadvantage of this solution, however, is that the sensitivity of the sensor is initially abruptly reduced when the aforementioned limit is exceeded, meaning that the sensor has a pressure-dependent and also non-linear sensitivity to the flow velocity or volume flow.

[0008] Based on this, one object of the invention is to improve sensors with a transducer element positioned on the deformation body so that, even with a comparatively simple mechanical design, they exhibit high compressive strength or a dependence of compressive strength on the operating temperature, allowing use in superheated steam applications with steam temperatures exceeding 200 °C and pressure peaks exceeding 100 bar. Furthermore, the sensor should be easily assembled from individual components, for example, to allow for easy replacement of a defective transducer element with a new, intact one.

[0009] To achieve the object, the invention consists in a sensor, in particular a sensor for detecting pressure fluctuations in a Kärmänschen vortex street formed in a flowing fluid, which sensor comprises:

[0010] • a deformation body which is at least partially flat, for example membrane-like or disc-shaped, for example made of a metal, with a flat first surface and an opposite flat second surface;

[0011] • a sensor flag extending from the first surface of the deformation body, for example rod-shaped, plate-shaped or wedge-shaped;

[0012] • a connecting sleeve extending from the deformation body, for example electrically conductively connected thereto, for example made of a metal and / or of a temperature range not less than 16 - 10 ® K at least within a temperature range between -10°C and 250°C 1 and / or not more than 17 - 10 ® K 1 material having a (linear) coefficient of thermal expansion;

[0013] • a transducer element arranged within the connecting sleeve, for example a disc-shaped and / or piezoceramic transducer element which makes contact with the second surface of the deformation body by means of a first contact surface, for example in an electrically conductive manner, for example made of a material which has a temperature range of at least -6 • 10 ® K within a temperature range of at least -10°C to 250°C 1 and / or not more than 6 - 10 ® K' 1 material having a (linear) thermal expansion coefficient, for generating a time-varying, for example at least temporarily periodic, movement of the sensor vane and / or a time-varying, for example at least temporarily periodic, electrical sensor signal representing deformations of the deformation body and / or for generating a force causing deformations of the deformation body (inverse piezo effect);

[0014] • as well as fastening means positioned within the connecting sleeve and thus mechanically connected, for example in a releasable manner, for fixing the converter element in the connecting sleeve, for example in a releasable manner.

[0015] In the sensor according to the invention, the connecting sleeve has an internal thread in a distal end remote from the deformation body and the fastening means also comprise an (internal) screw sleeve having an external thread and a cylindrical, for example monolithic and / or disc-shaped and / or metallic, shim element, for example made of a metal and / or of a temperature range not less than 20 • 10 ® K at least within a temperature range between -10°C and 250°C. 1 and / or not more than 30 • 10 ® K 1material having a (linear) thermal expansion coefficient. In addition, the (inner) screw sleeve is screwed into the inner thread and the shim element is positioned between the (inner) screw sleeve in such a way that an abutment for the shim element is formed by means of the (inner) screw sleeve and at least the shim element is elastically deformed by exerting a contact force that holds the converter element pressed against the deformation body or by forming at least one force connection that connects the converter element and the deformation body, for example in such a way that a minimum surface pressure acting between the shim element and the converter element or between the converter element and the deformation body is more than 1 MPa and / or a minimum surface pressure acting between the shim element and the converter element orthe maximum surface pressure acting between the converter element and the deformation body is less than 20 MPa and / or such that a force-locking connection is formed between the converter element and the deformation body.

[0016] Furthermore, the invention also consists in a measuring system for measuring at least one, for example time-varying, flow parameter, for example a flow velocity and / or a volume flow rate, of a fluid flowing in a pipeline, which measuring system is formed by means of a sensor according to the invention which is used to detect pressure fluctuations in the flowing fluid, for example namely for detecting pressure fluctuations in a Kärmän vortex street formed in the flowing fluid, which measuring system further comprises measuring electronics which are electrically connected to the transducer element of the sensor and are set up to receive and process the sensor signal from the sensor, for example namely to generate measured values ​​representing the at least one flow parameter and / or to feed an electrical driver signal into the transducer element which is used, for example, to generate a force causing deformation of the deformation body.The measuring system according to the invention can in particular also be used to measure a flow parameter - for example a flow velocity and / or a volume flow rate and / or a mass flow rate - of a fluid, for example a steam, flowing in a pipeline, for example at least temporarily having a temperature of more than 200°C and / or at least temporarily acting on the deformation body and / or the sensor vane of the sensor with a pressure of more than 100 bar.

[0017] According to a first embodiment of the sensor of the invention, it is provided that the transducer element has a (first) thickness d12, for example, not less than 0.5 mm and / or not more than 2 mm, measured at a temperature of 20°C as the maximum extension in the direction of a normal of its first contact surface, and the shim element has a (second) thickness d133, for example, not less than 1 mm and / or not more than 10 mm, measured at a temperature of 20°C as the maximum extension in the direction of the normal of the first contact surface of the transducer element, and it is further provided that the transducer element and the shim element are designed such that an expansion difference ratio Aoc21 / Aoc31 (of the sensor),measured as a ratio of a difference between a (linear) thermal expansion coefficient oc2 (of the material) of the transducer element and a (linear) thermal expansion coefficient a1 (of the material) of the connecting sleeve to a difference between a (linear) thermal expansion coefficient oc3 (of the material) of the shim element and the (linear) thermal expansion coefficient a1 (of the material) of the connecting sleeve, for example at least within a temperature range between -10°C and 250°C, a condition dependent on a (fine-tuning) parameter k1:, is fulfilled, wherein the (fine-tuning) parameter k1 is not less than 0.5 and not greater than 1.5, in particular greater than 0.7 and / or less than 1.2. Further developing this embodiment of the invention, it is further provided that a (thickness) ratio d 3 / di2 of the (first) thickness ds of the shim element to the (second) thickness di2 of the transducer element is more than 0.5 and less than 7, for example not less than 2 and / or not more than 4.

[0018] According to a second embodiment of the sensor of the invention, it is further provided that the fastening means comprise a, for example, annular, spherical disc, for example made of a metal and / or of a material which has a temperature range of at least between -10°C and 250°C of not less than 16 • 10 ® K 1 and / or not more than 17 • 10 ® K 1material having a (linear) thermal expansion coefficient a4, and that the spherical disc is positioned between the screw sleeve and the shim element. Further developing this embodiment of the invention, it is further provided that the spherical disc is made at least partially, for example predominantly or completely, of a metal, for example a stainless steel or a nickel-based alloy, and / or that a (linear) thermal expansion coefficient a4 (of the material) of the spherical disc differs from a (linear) thermal expansion coefficient a1 (of the material) of the connecting sleeve by less than 2 - 10 ® K, at least within a temperature range between -10°C and 250°C. 1 and / or deviates by less than 10% of the thermal expansion coefficient a1 (of the material) of the connecting sleeve.

[0019] According to a third embodiment of the sensor of the invention, it is further provided that the fastening means comprise an insulating disc (135), in particular annular, in particular made of a ceramic and / or a plastic and / or of a material which has a temperature range of at least between -10°C and 250°C of not less than 30 • 10 ® K 1 and / or not more than 50 • 10 ® K 1 material having a (linear) thermal expansion coefficient a5, and that the insulating disc is positioned between the converter element and the shim element. Further developing this embodiment of the invention, it is further provided that the insulating disc is made at least partially, for example predominantly or completely, of a material, in particular a material that is resistant to high temperatures and / or of a material that has a temperature range of at least between -10°C and 250°C of not less than 20 • 10 ® K 1 and / or not more than 40 • 10 ® K 1plastic, for example a polyimide (Kapton), having a (linear) thermal expansion coefficient a5 and / or that a (linear) thermal expansion coefficient a5 (of the material) of the insulating disc differs from a (linear) thermal expansion coefficient a2 (of the material) of the shim element by less than 20 • 10 ® K at least within a temperature range between -10°C and 250°C 1 and / or by less than 50% of the (linear) thermal expansion coefficient a2 (of the material) of the shim element. Alternatively or additionally, the insulating disc may also have a (third) thickness, measured at a temperature of 20°C as the maximum expansion in the direction of the normal to the first contact surface of the transducer element, which is not less than 0.05 mm and / or not more than 0.5 mm.

[0020] According to a fourth embodiment of the sensor of the invention, it is further provided that the deformation body and the sensor flag are connected to one another in a materially bonded manner, for example, namely welded or soldered to one another.

[0021] According to a fifth embodiment of the sensor of the invention, it is further provided that the transducer element and the deformation body are not connected to one another in a materially bonded manner.

[0022] According to a sixth embodiment of the invention, it is further provided that the converter element and the shim element are not connected to one another in a materially bonded manner.

[0023] According to a seventh embodiment of the sensor of the invention, it is further provided that the shim element and the deformation body consist of different materials.

[0024] According to an eighth embodiment of the sensor of the invention, it is further provided that the shim element consists of an aluminum alloy, for example an aluminum-magnesium-silicon alloy (AlMgSi) or a wrought aluminum alloy of the (standardized) type EN AW-6061 (AlMglSiCu), EN AW-6082, EN AW-7075 or EN AW-5052.

[0025] According to a ninth embodiment of the sensor of the invention, it is further provided that the shim element consists of a metal, for example aluminum or an aluminum alloy.

[0026] According to a tenth embodiment of the sensor of the invention, it is further provided that the deformation body consists at least partially, for example predominantly or completely, of a metal, for example a stainless steel or a nickel-based alloy.

[0027] According to an eleventh embodiment of the sensor of the invention, it is further provided that the sensor flag consists at least partially, for example predominantly or completely, of a metal, for example a stainless steel or a nickel-based alloy.

[0028] According to a twelfth embodiment of the sensor of the invention, it is further provided that the connecting sleeve is made at least partially, for example predominantly or entirely, of a metal, for example, stainless steel or a nickel-based alloy. According to a thirteenth embodiment of the sensor of the invention, it is further provided that the deformation body and sensor lug, for example, the connecting sleeve, deformation body, and sensor lug, are made of the same material.

[0029] According to a fourteenth embodiment of the sensor of the invention, it is further provided that the deformation body and the sensor flag, for example the connecting sleeve, the deformation body and the sensor flag, are components of one and the same monolithic molded part.

[0030] According to a fifteenth embodiment of the sensor of the invention, it is further provided that a minimum surface pressure acting between the shim element and the transducer element or between the transducer element and the deformation body, in particular at a temperature above -50°C and below 250°C, is more than 1 MPa, for example even more than 3 MPa.

[0031] According to a sixteenth embodiment of the sensor of the invention, it is further provided that a maximum surface pressure acting between the shim element and the transducer element or between the transducer element and the deformation body, in particular at a temperature above -50°C and below 250°C, is less than 20 MPa, for example also less than 15 MPa.

[0032] According to a seventeenth embodiment of the sensor of the invention, it is further provided that the transducer element electrically conductively contacts the deformation body and / or the connecting sleeve.

[0033] According to a first development of the sensor of the invention, the sensor further comprises a metal foil, for example a silver foil.

[0034] According to a second development of the sensor of the invention, the sensor further comprises a compensating body extending from the second surface of the deformation body, for example rod-shaped or plate-shaped or sleeve-shaped, for compensating forces and / or moments resulting from joint movements of the deformation body and the sensor vane.

[0035] According to a first embodiment of the first development of the invention, it is further provided that the compensating body extends through the shim element, for example, such that a main axis of inertia (for example, a longitudinal axis) of the compensating body and a main axis of inertia (for example, a longitudinal axis) of the shim element run parallel to each other, for example, coincident, and / or such that the shim element and compensating body do not contact each other. According to a second embodiment of the first development of the invention, it is further provided that the deformation body and compensating body are integrally connected to each other, for example, welded or soldered.

[0036] According to a third embodiment of the first further development of the invention, it is further provided that the sensor flag and the compensating body are arranged in alignment with one another.

[0037] According to a fourth embodiment of the first further development of the invention, it is further provided that the compensating body and the deformation body are positioned and aligned with each other in such a way that a main axis of inertia of the deformation body extends parallel to a main axis of inertia of the compensating body, for example coincides therewith.

[0038] According to a fifth embodiment of the first further development of the invention, it is further provided that the deformation body and the compensating body are components of one and the same monolithic molded part, for example in such a way that the sensor lug, the deformation body and the compensating body and / or that the connecting sleeve, the deformation body and the compensating body are components of the same molded part.

[0039] According to a sixth embodiment of the first further development of the invention, it is further provided that the compensating body consists at least partially, for example predominantly or completely, of a metal, for example a stainless steel or a nickel-based alloy.

[0040] According to a seventh embodiment of the first further development of the invention, it is further provided that the deformation body and the compensating body are made of the same material, for example in such a way that the sensor lug, the deformation body and the compensating body and / or that the connecting sleeve, the deformation body and the compensating body are made of the same material.

[0041] According to a further development of the measuring system of the invention, the measuring system further comprises a tube which can be inserted into the course of the same pipeline and has a lumen which is designed to guide the fluid flowing in the pipeline.

[0042] According to a first embodiment of the further development of the measuring system of the invention, it is further provided that the sensor is inserted into the same tube in such a way that the first surface of the deformation body faces the lumen of the tube and that the sensor flag projects into the same lumen.

[0043] According to a second embodiment of the further development of the measuring system of the invention, it is further provided that an opening is formed in the wall of the tube, in particular having a holder for holding the deformation body on the wall, and that the sensor is inserted into the same opening in such a way that the deformation body covers the opening, in particular hermetically seals it, and that the first surface of the deformation body faces the lumen of the tube, thus the sensor flag projects into the same lumen.

[0044] According to a third embodiment of the further development of the measuring system of the invention, it is further provided that the sensor flag has a length, measured as the minimum distance between a proximal end of the sensor flag, namely the end bordering the deformation body, to a distal end of the sensor flag, namely the end remote from the deformation body or its surface, which length corresponds to less than 95% of a caliber of the tube and / or more than half of the same caliber.

[0045] According to a fourth embodiment of the further development of the measuring system of the invention, it is further provided that the measuring system further comprises a bluff body arranged in the lumen of the pipe, for example upstream, namely in the (main) flow direction in front of the sensor, which is designed to cause a Kärmäns vortex street in the flowing fluid, wherein the sensor is designed to detect periodic pressure fluctuations in the Kärmäns vortex street and to convert them into a sensor signal, for example in such a way that the sensor signal has a signal frequency corresponding to a detachment rate of vortices forming the Kärmäns vortex street on the bluff body.

[0046] A basic idea of ​​the invention is to bring about the desired high nominal compressive strength for sensors, not least at high operating temperatures of over 200°C, and the desired improvement in the dependence of the compressive strength of the sensor assembly on the operating temperature (pressure-temperature curve of the sensor assembly) by holding a transducer element arranged on the deformation body by means of an (internal) screw sleeve and a (disk- or sleeve-shaped) shim, for example in the form of an (aluminium) washer, against the deformation body over a comparatively wide temperature range, for example from -10°C to 250°C, continuously with a surface pressure that is suitable for the measuring principle, namely that it is both sufficient and compatible. One advantage of the invention is that it not only provides a very simple way of significantly improving the nominal compressive strength orthe pressure-temperature curve of sensors of the type in question, but that this is achieved without significantly reducing the measurement sensitivity, namely the sensitivity of the sensor to the pressure fluctuations actually intended to be detected. A further advantage of the invention is that defective components in the sensor according to the invention, such as the transducer element or the fastening means, can be replaced very easily, for example, even on-site.

[0047] The invention and advantageous embodiments thereof are explained in more detail below with reference to exemplary embodiments shown in the figures of the drawing. Identical or equivalent or similarly functioning parts are provided with the same reference numerals in all figures; where clarity requires it or it otherwise seems expedient, previously mentioned reference numerals have been omitted in subsequent figures. Further advantageous embodiments or developments, in particular combinations of partial aspects of the invention initially only explained individually, will become apparent from the figures of the drawing and / or from the claims. In detail: Fig. 1, 2 show schematically in different views an exemplary embodiment of a measuring system - designed here as a vortex flow meter - with a sensor and measuring electronics for measuring at least one flow parameter of a fluid flowing in a pipeline;

[0048] Fig. 3 shows a schematic sectional side view of an embodiment of a sensor, particularly suitable for use in a measuring system according to Fig. 1 or 2; and

[0049] Fig. 4a, 4b schematically show in two different side views an embodiment of a transducer element suitable for a sensor according to Fig. 3.

[0050] Figs. 1 and 2 show an exemplary embodiment of a measuring system for measuring at least one, possibly also time-varying flow parameter, such as a flow velocity v and / or a volume flow V', of a fluid flowing in a pipeline, for example a hot gas, in particular one having a temperature of more than 200°C at least temporarily, and / or at least temporarily under high pressure, in particular more than 100 bar. The pipeline can be designed, for example, as a system component of a heat supply network or a turbine cycle; thus, the fluid can be, for example, steam, in particular saturated steam or superheated steam, or, for example, condensate discharged from a steam line. However, the fluid can also be, for example, a (compressed) natural gas or biogas; thus, the pipeline can also be, for example, a component of a natural gas or biogas plant or a gas supply network.

[0051] The measuring system has a sensor 1 - shown again enlarged in Fig. 3 - which is intended or designed to detect pressure fluctuations in the fluid flowing past the sensor in a (main) flow direction and to convert them into a sensor signal s1 corresponding to these pressure fluctuations, for example an electrical or optical one. As can be seen from the combination of Figs. 1 and 2, the measuring system further comprises measuring electronics 2 - housed, for example, in a pressure- and / or impact-resistant protective housing 20 - which is connected to the sensor 1 or communicates with the sensor 1 during operation of the measuring system. According to one embodiment of the invention, the measuring electronics 2 is designed to receive and process the sensor signal s1, for example to generate measured values ​​XM ZU representing at least one flow parameter, for example the flow velocity v or the volume flow rate V'.The measured values ​​XM can, for example, be visualized on site and / or transmitted - wired via a connected fieldbus and / or wirelessly via radio - to an electronic data processing system, such as a programmable logic controller (PLC) and / or a process control station. Alternatively or additionally, the measuring electronics 2 can also be used or configured to feed an electrical drive signal into the transducer element, for example, for generating a force that causes deformation of the deformation body. The protective housing 20 for the measuring electronics 2 can, in turn, be made, for example, from a metal, such as stainless steel or aluminum, and / or by means of a casting process, such as an investment casting or a high-pressure die-casting process (HPDC); however, it can also be formed, for example, by means of a plastic molded part produced by an injection molding process.

[0052] The sensor 1 comprises, as also shown in Fig. 3 or as is readily apparent from a combination of Figs. 2 and 3, a deformation body 111, in particular a membrane-like or disc-shaped deformation body. The deformation body 111 further has a second surface 111# opposite the first surface 111+, for example at least partially parallel to the first surface 111+. In addition, the sensor can further comprise a sensor flag 112 having a left-hand first side surface and a right-hand second side surface, which extends from a first surface 111+ of the deformation body 111 to a distal (free) end, namely remote from the deformation body 111 or its surface 111+.The deformation body 111 and the aforementioned sensor flag 112 can, for example, be components of one and the same monolithic molded part, which is, for example, cast or produced by a generative process such as 3D laser melting; however, the deformation body and sensor flag can also be designed as individual parts that are initially separate from one another or are only subsequently joined to one another in a material-to-material manner, for example welded or soldered to one another, and can therefore be manufactured from materials that can be joined to one another in a material-to-material manner. The deformation body 111 can consist at least partially, for example predominantly or completely, of a metal, such as, for example, stainless steel or a nickel-based alloy, such as, for example, X7 CrNiAl 17-7 (WsNr 1.4568, EN 10027-2:1992-09). Likewise, the aforementioned sensor flag 112 can also be made at least partially of a metal, for example, stainless steel ora nickel-based alloy, and / or the deformation body 111 and the sensor vane 112 can be made of or consist of the same material. The deformation body 111 and the sensor vane 112 are also specifically designed to be excited to oscillate around a common static rest position, typically forced oscillation outside of resonance, such that the sensor vane 112 executes pendulum movements that elastically deform the deformation body 111 in a detection direction that runs essentially transversely to the aforementioned flow direction. The sensor vane 112 accordingly has a width, measured as a maximum extension in the direction of flow, which is significantly greater than a thickness of the sensor vane 112, measured as a maximum lateral extension in the direction of detection.The sensor flag 112 can also, as is quite common with such sensors, be wedge-shaped, for example, or even designed as a flat plate. The sensor 1 according to the invention further comprises a connecting sleeve 113 extending from a, for example, circular, peripheral edge segment of the second surface 111# of the deformation body, for example, electrically conductively connected to the deformation body and / or made of metal. According to a further embodiment of the invention, the connecting sleeve 113 is made of a material or metal that has a temperature range of at least 16-10°C, at least within a temperature range between -10°C and 250°C. 1 and / or not more than 17 - 10 ® K 1 amounting to a (linear) thermal expansion coefficient a1.

[0053] To detect mechanical vibrations of the deformation body 111 (or of the deformation body 111 together with the sensor vane), the sensor further comprises at least one transducer element 12, in particular a disc-shaped and / or piezoceramic element, arranged within the connecting sleeve 113 and contacting the surface 111+ of the deformation body with a first contact surface, for generating a temporally varying, in particular at least temporarily periodic, movement of the sensor vane or an electrical sensor signal representing equally temporally varying, in particular at least temporarily periodic, deformations of the deformation body 111, for example with an electrical (alternating) voltage corresponding to the aforementioned movements. Alternatively or additionally, the transducer element 12 can also serve to generate a force causing deformation of the deformation body 111 (inverse piezoelectric effect).to be used as a (piezoelectric) actuator, for example, for exciting mechanical vibrations of the deformable body. According to a further embodiment of the invention, the transducer element 12 is made of a material, for example, a lead zirconate titanate (piezo) ceramic (PZT), which has a temperature range of at least -6 • 10 ® K within a temperature range of -10°C to 250°C. 1 and / or not more than 6 - 10 ® K 1 amounting to (linear) thermal expansion coefficients a2.

[0054] As already mentioned, the sensor 1 or the measuring system formed therewith is particularly also intended for use in applications or measuring points in which, for example due to condensation-induced water hammer (CIWH), extremely high hydrostatic pressures, namely pressures acting perpendicularly against the wall 3* of the pipe and thus equally acting against the sensor, of over 100 bar and / or high (fluid) temperatures of over 200°C can occur in the fluid to be measured, for example in superheated steam applications. For, in particular, re-detachable fixing of the transducer element 12 in the connecting sleeve 113 on the one hand and for achieving the lowest possible sensitivity of the sensor to pressure surges and / or temperature fluctuations orIn order to reduce measurement errors resulting from such high loads on the sensor when measuring the at least one flow parameter with the measuring system formed with the same sensor, on the other hand, the sensor according to the invention further comprises fastening means 13 positioned within the connecting sleeve 113 and mechanically connected thereto, in particular releasably. In the sensor according to the invention, the fastening means 13 comprise an (internal) screw sleeve 132 having an external thread, for example made of a metal, and a shim element 133, for example made of a metal or the same material as the connecting sleeve 112, which is monolithic and / or cylindrical. In addition, the connecting sleeve 112 has an internal thread (for the screw sleeve 132) in a distal end remote from the deformation body 111. As shown in Fig.3, the transducer element 12 has a (first) thickness d12, for example not less than 1 mm and / or not more than 2 mm, measured at a temperature of 20°C as the maximum extension in the direction of a normal of its first contact surface, and the shim element 133 has a (second) thickness d131, for example not less than 0.5 mm and / or not more than 10 mm, measured at room temperature or a temperature of 20°C as the maximum extension in the direction of the normal of the first contact surface of the transducer element.

[0055] According to a further embodiment of the invention, the shim element 133 is designed as a washer, for example in the form of a shim or a spacer washer, and / or is made of a material, for example a metal, which is different from the material of the deformation body and / or which has a temperature range of at least between -10°C and 250°C of not less than 20 • 10 ® K 1 and / or not more than 30 • 10 ® K 1 (linear) thermal expansion coefficients a3. Alternatively or additionally, it is further provided that the shim element 133 consists of aluminum or an aluminum alloy, for example an aluminum-magnesium-silicon alloy (AlMgSi) or a wrought aluminum alloy, in particular of the (standardized) type EN AW-6061 (AlMglSiCu), EN AW-6082, EN AW-7075 or EN AW-5052.

[0056] The (internal) screw sleeve 132 is further screwed into the internal thread of the connecting sleeve 112, forming an abutment for the shim element 133, and the shim element 131 is positioned between the (internal) screw sleeve 132 and the converter element 12. Furthermore, the (internal) screw sleeve is screwed into the connecting sleeve 112 to such an extent that at least the shim element 131 (in the installed state) is elastically deformed by exerting a contact force that holds the converter element 12 pressed against the deformation body 111, whereby a force-locking connection is also formed between the converter element 12 and the deformation body 111. this in particular in such a way that a minimum surface pressure acting between the shim element 131 and the transducer element 12 or between the transducer element 12 and the deformation body 111 is more than 1 MPa, in particular, at least within a temperature range between -10°C and 250°C.more than 3 MPa, and / or that a maximum surface pressure acting between the shim element 131 and the transducer element 12 or between the transducer element 12 and the deformation body 111 is less than 20 MPa, in particular less than 15 MPa, at least within a temperature range between -10°C and 250°C. The required (nominal) contact force or (nominal) surface pressure can be precisely adjusted during assembly of the sensor, for example by means of an appropriately programmed screwing tool, such as a programmable electronic torque and / or angle wrench. Not least in order to achieve the most precisely adjusted orIn order to maintain a constant surface pressure even over a wide temperature range, for example between -10°C and 250°C, according to a further embodiment of the invention, the transducer element 12 and the shim element 133 are designed such that an expansion difference ratio Aoc21 / Aoc31 (of the sensor), measured as a ratio of a difference between the aforementioned (linear) thermal expansion coefficient a2 (of the material) of the transducer element 12 and a (linear) thermal expansion coefficient a1 (of the material) of the connecting sleeve 113 to a difference between a (linear) thermal expansion coefficient a3 (of the material) of the shim element 133 and the (linear) thermal expansion coefficient a1 (of the material) of the connecting sleeve 113, in particular at least within the aforementioned temperature range between -10°C and 250°C, a (Fine-tuning) parameter k1 dependent condition:. is fulfilled, wherein the (fine-tuning) parameter k1 is not less than 0.5 and not greater than 1.5, for example also greater than 0.7 and / or also less than 1.2. It may also be advantageous to select the thickness ds and the thickness di 2 such that a (thickness) ratio di 33 / di2 (the thickness ds of the shim element 133 to the thickness di2 of the transducer element 12) is more than 0.5 and less than 7, for example also not less than 2 and / or not more than 4.

[0057] To prevent lateral displacement of the transducer element 12 in the installed position relative to the deformation body 111 or the connecting sleeve 113, the connecting sleeve 113 and the transducer element 12 can advantageously also be designed such that an inner diameter of the connecting sleeve 113 in the region of the installed position of the transducer element essentially corresponds to a corresponding outer diameter of the transducer element 12, for example, being larger by only an amount just enough to allow the transducer element 12 to be positioned on the deformation body 111. To facilitate the positioning of the transducer element 12, the connecting sleeve 113 can further be designed such that, in a region above the transducer element 12 (positioned in the installed position), it has a (smallest) inner diameter that is larger—for example, by more than 1 mm—than a (largest) outer diameter of the transducer element 12.Alternatively or additionally, the fastening means can further comprise a spherical washer 134, not least for the purpose of simplifying assembly and / or compensating for any manufacturing-related tolerances of the screw sleeve and / or the shim element, which is positioned (in the installed position) between the (inner) screw sleeve and the shim element 133. The spherical washer 134, which is for example annular, can advantageously be made at least partially, for example predominantly or completely, from a metal, in particular a stainless steel or a nickel-based alloy, and / or from a material which has a temperature range of at least between -10°C and 250°C of not less than 16 • 10 ® K. 1 and / or not more than 17 • 10 ® K 1In addition, the (linear) thermal expansion coefficient a4 (of the material) of the spherical disk can advantageously also be selected such that it differs from the aforementioned (linear) thermal expansion coefficient a1 (of the material) of the connecting sleeve 113 by less than 2 - 10 ® K, at least within a temperature range between -10°C and 250°C. 1 and / or deviates by less than 10% of the thermal expansion coefficient a1 (of the material) of the connecting sleeve 113.

[0058] In order to easily ensure the correct alignment of the transducer element 12 in the installed position, not least with regard to an electrical polarization of the ceramic forming the transducer element 12 or a correct position of positively (+) or negatively (-) polarized partial areas of the transducer element 12, the transducer element 12 and the connecting sleeve 113 can further be shaped such that the transducer element 12 and the connecting sleeve 113 have outer and inner contours that are complementary to one another but nevertheless prevent an incorrect installation position of the transducer element, for example such that, as shown in Fig. 4a and 4b or as can be seen from their combination, the transducer element 12 has an outer contour with one or more straight sections 12a and that the connecting sleeve 113 has an inner contour with straight sections that correspond to the aforementioned straight sections of the transducer element 12.

[0059] The use of such fastening means formed by the (internal) screw sleeve 132 and the shim element 133 also makes it possible, among other things, to fix the transducer element 12 on the deformation body 111 without the transducer element 12 and the deformation body 111 being or having to be materially bonded to one another. Thus, for example, the use of adhesives or solders to connect the transducer element 12 and the deformation body 111 can be dispensed with. Likewise, the shim element 133 and the transducer element 12 can also be connected to one another in a non-materially bonded manner, namely by avoiding a material bond between the shim element 133 and the transducer element. Thus, here too, the use of adhesives or solders can be dispensed with.On the other hand, the inventive use of the shim element 133 also makes it easy to position a metal foil, for example a silver foil, between the transducer element 12 and the deformation body 111, which serves to create a highly electrically conductive connection between the transducer element 12 and the deformation body 111 and / or to create the most uniform mechanical contact possible between the transducer element 12 and the deformation body 111. Furthermore, it is also easily possible to place further elements of the fastening means 13 between the transducer element 12 and the shim element 131, for example one or more electrically insulating insulating disks (135), possibly also designed as a contact disk or (flexible) printed circuit board.According to a further embodiment of the invention, the fastening means accordingly comprise at least one insulating disc 135, for example annular and / or formed by means of a flexible printed circuit board, for example made of a ceramic and / or a plastic and / or of a temperature range not less than 30 • 10 ® K at least within a temperature range lying between -10°C and 250°C. 1 and / or not more than 50 • 10 ® K 1 material having a (linear) thermal expansion coefficient a5, which is positioned between the converter element 12 and the shim element 133. Advantageously, the insulating disc 135 can also be made at least partially, for example predominantly or completely, of a material, in particular a high-temperature-resistant material and / or of a material having a temperature range of at least between -10°C and 250°C of not less than 20 • 10 ® K 1 and / or not more than 40 • 10 ® K' 1plastic having a (linear) thermal expansion coefficient a5, for example a polyimide, in particular Kapton, or a plastic having a (linear) thermal expansion coefficient a5, which differs from the (linear) thermal expansion coefficient a2 (of the material of the shim element 133) by less than 20 • 10 ® K at least within a temperature range between -10°C and 250°C 1and / or deviates by less than 50% of the (linear) thermal expansion coefficient a2, and / or the insulating disc 135, not least in the above-described case that the insulating disc is made of polyimide, in particular Kapton, can have a (third) thickness d3 of not less than 0.05 mm and / or not more than 0.5 mm, measured at a temperature of 20°C as the maximum expansion in the direction of the normal of the above-described first contact surface of the transducer element 12, and can therefore also be designed as a (polyimide) film.Alternatively or additionally, the insulating disc 135 can have electrically conductive conductor tracks positioned thereon and / or can be electrically conductively connected to the electrical connecting line 14 and the insulating disc 135 can be positioned such that, in the installed position, it makes electrically conductive contact with a second contact surface of the converter element 12 opposite the aforementioned first contact surface of the converter element 12.

[0060] According to a further embodiment of the invention, the measuring system further comprises a pipe 3 insertable into the aforementioned pipeline, having a lumen 3' enclosed by a—for example, metallic—wall 3* of the pipe, which extends from an inlet end 3+ to an outlet end 3# and is designed to guide the fluid flowing in the pipeline. The sensor 1 is also inserted into the same pipe in such a way that the first surface of the deformation body 111 faces the lumen 3' of the pipe, thus the sensor flag protrudes into the same lumen. In the embodiment shown here, a leak-free flange connection is provided at the inlet end 3+ as well as at the outlet end 3#, each serving to create a leak-free flange connection with a corresponding flange on a line segment on the inlet or outlet side of the pipeline. Furthermore, the pipe 3, as shown in Fig.1 or 2, be essentially straight, for example, namely as a hollow cylinder with a circular cross-section, such that the tube 3 has an imaginary straight longitudinal axis L imaginarily connecting the inlet end 3+ and the outlet end 3#. In the embodiment shown in Fig. 1 or 2, the sensor 1 is inserted from the outside through an opening 3" formed in the wall into the lumen of the tube and is fixed in the region of the same opening - for example, also detachably again - from the outside to the wall 3*, specifically in such a way that the surface 111+ of the deformation body 111 faces the lumen 3' of the tube 3, and thus the sensor flag 112 projects into the same lumen. In particular, the sensor 1 is inserted into the opening 3" in such a way that the deformation body 111 covers or hermetically seals the opening 3".Said opening can, for example, be designed such that it has an (inner) diameter in a range between 10 mm and approximately 50 mm, as is quite common in measuring systems of the type in question. According to a further embodiment of the invention, a holder 3a is formed in the opening 3" to hold the deformation body 111 or the sensor 1 formed thereby on the wall 3*. The sensor 1 can be fixed to the tube 3, for example, by a material-to-material connection, in particular by welding or soldering, of the deformation body 111 and the wall 3*; however, it can also be detachably connected to the tube 3, for example by being screwed or screwed on. Furthermore, at least one sealing surface, for example a circumferential or annular sealing surface, can be formed in the holder 3a, which is designed to interact with the deformation body 111 and a possiblyprovided, for example, annular or annular disk-shaped sealing element to seal the opening 3" accordingly. According to a further embodiment of the invention, the sensor 1 and the tube 3 are further dimensioned such that a length of the sensor flag 112, measured as the minimum distance between a proximal end of the sensor flag 112, namely the end bordering the deformation body 111, to the distal end of the sensor flag 112, corresponds to more than half a caliber DN of the tube 3 or less than 95% of the same caliber DN. The length of the sensor flag 112 can, for example - as is quite common with comparatively small calibers of less than 50 mm - also be selected such that the said distal end of the sensor flag 112 has only a very small minimum distance from the wall 3* of the tube 3. For tubes with a comparatively large caliber of 50 mm or more, the sensor flag 112 can - as is quite common with measuring systems of the type in question oras can be seen from Fig. 2 - for example, it can also be designed to be significantly shorter than half a caliber of the tube 3. In the embodiment shown in Fig. 1 or 2, the measuring system is specifically designed as a vortex flow measuring device with a bluff body 4 arranged in the lumen of the tube 3 - here upstream of the sensor 1, namely in front of the sensor as seen in the (main) flow direction - and serving to cause a Kärmänsche vortex street in the flowing fluid. The sensor and bluff body are specifically dimensioned and arranged so that the.

[0061] Sensor vane 112 projects into the lumen 3* of the tube or the fluid conveyed therein in such an area that, during operation of the measuring system, is regularly occupied by a (stationary) Kärmän vortex street, so that the pressure fluctuations detected by sensor 1 are periodic pressure fluctuations caused by vortices detached from the bluff body 4 at a detachment rate (~ 1 / fvtx), and the sensor signal s1 has a signal frequency (~ fvtx) corresponding to the detachment rate of these vortices. In the exemplary embodiment shown here, the vortex flow measuring device is also designed as a compact measuring system in which the measuring electronics 2 are housed in a protective housing 20 attached to the tube, for example, by means of a neck-shaped connecting piece 30.

[0062] To compensate for forces and / or moments resulting from any movements of the sensor—for example, due to vibration of the aforementioned pipeline connected to the pipe—or to avoid undesirable movements of the sensor vane or the deformation body 111 resulting therefrom, namely movements that distort the sensor signal s1, the sensor 1 according to a further embodiment of the invention further comprises a compensating body 114, for example, rod-, plate-, or sleeve-shaped, extending from the second surface 111# of the deformation body 111. The compensating body 114 can, for example, be made of the same material as the deformation body and / or the sensor vane, for example, a metal. For example, the compensating body 114 can be made of stainless steel or a nickel-based alloy.According to a further embodiment of the invention, deformation body 111 and compensating body 114 are integrally connected to one another, for example, welded or soldered together. Thus, it is provided that compensating body 114 and deformation body 111 are manufactured from materials that can be integrally connected to one another. Alternatively, deformation body 111 and compensating body 114 can also be components of one and the same monolithic molded part, for example, such that sensor flag 111, deformation body 112, and compensating body 114 are components of the same molded part. Furthermore, as can be seen from a synopsis of Figs. 3c and 3d, the sensor flag 112 and the compensating body 114 can be arranged in alignment with one another in such a way that a principal axis of inertia of the sensor flag 112 coincides in extension with a principal axis of inertia of the compensating body 114.Alternatively or additionally, the compensating body 114 and the deformation body 111 can also be positioned and aligned with one another such that a principal axis of inertia of the deformation body 111 coincides with a principal axis of inertia of the compensating body 114. According to a further embodiment of the invention, the compensating body 114 and the shim element 133 are also designed and arranged such that the compensating body 114 extends through the shim element 133, for example such that a principal axis of inertia, for example a longitudinal axis, of the compensating body and a principal axis of inertia, for example a longitudinal axis, of the shim element run parallel to one another, in particular are coincident, and / or such that the shim element and the compensating body do not contact one another.

Claims

PATENT CLAIMS 1. Sensor, in particular a sensor for detecting pressure fluctuations in a fluid, which sensor includes: - a deformation body (111) that is at least partially flat, especially membranous or disc-shaped, especially made of a metal, with a flat first surface (111+) and an opposing flat second surface (111#); - a connecting sleeve (113) extending from the deformation body, in particular electrically connected to it, in particular made of a metal and / or of a material, with a temperature range of at least 16 • 10 ® K within a range between -10°C and 250°C 1 and / or not more than 17 • 10 ® K 1 material exhibiting a (linear) coefficient of thermal expansion a1; - a disc-shaped, piezoceramic transducer element (12) arranged within the connecting sleeve (113), contacting the second surface (111+) of the deformation body with a first contact surface, in particular electrically conductive, in particular made of a temperature range not less than -6 • 10 ® K' within a temperature range at least within a range between -10°C and 250°C 1 and / or no more than 6 - 10 ® K 1 amounting to (linear) thermal expansion coefficient a2 material, for generating a time-varying, in particular at least temporarily periodic, electrical sensor signal representing deformations of the deformation body and / or for generating a force causing deformations of the deformation body; - as well as fastening means positioned within the connection sleeve (113) and thus at least partially, in particular releasably, mechanically connected for fixing the converter element (12) in the connection sleeve (113), in particular releasably; - wherein the connecting sleeve has an internal thread at a distal end away from the deformation body (111); - wherein the fastening means (13) - a (internal) screw sleeve having an external thread (132) - and a cylindrical, in particular monolithic and / or disc-shaped and / or metallic, shim element (133), in particular made of a metal and / or of a material, with a temperature range not less than 20 • 10 ® K within a range between -10°C and 250°C 1 and / or no more than 30 • 10 ® K 1 material exhibiting a (linear) coefficient of thermal expansion a3; - and wherein the (inner) screw sleeve (132) is screwed into the internal thread and the shim element (133) is positioned between the (inner) screw sleeve and the converter element, such that a support for the shim element is formed by means of the (inner) screw sleeve and at least the shim element is elastically deformed by exerting a contact force holding the converter element against the deformation body or by forming at least a force-fit connecting the converter element and the deformation body, in particular such that a minimum surface pressure acting between the shim element and the converter element or between the converter element and the deformation body is more than 1 MPa and / or a maximum surface pressure acting between the shim element and the converter element or between the converter element and the deformation body is less than 20 MPa and / or such that a force-fit connection is formed between the converter element and the deformation body.

2. Sensor according to one of the preceding claims, - wherein a minimum surface pressure acting between the insert element and the converter element or between the converter element and the deformation body, in particular at a temperature above -50°C and below 250°C, is more than 1 MPa, in particular more than 3 MPa; and / or - wherein the maximum surface pressure acting between the insert element and the converter element (12) or between the converter element and the deformation body, in particular at a temperature above -50°C and below 250°C, is less than 20 MPa, in particular less than 15 MPa.

3. Sensor according to one of the preceding claims, wherein the insert element is made of an aluminum alloy, in particular an aluminum-magnesium-silicon alloy (AIMgSi) or an aluminum wrought alloy of the (standardized) grade EN AW-6061 (AIMgl SiCu), EN AW-6082, EN AW-7075 or EN AW-5052.

4. Sensor according to any of the preceding claims, - wherein the washer element (133) consists of a metal, in particular aluminium or an aluminium alloy; and / or - wherein the deformation body consists at least partially, in particular predominantly or completely, of a metal, in particular a stainless steel or a nickel-based alloy; and / or - wherein the connecting sleeve (113) consists at least partially, in particular predominantly or completely, of a metal, in particular a stainless steel or a nickel-based alloy; and / or - wherein the shim (133) and the deformation body are made of different materials.

5. Sensor according to any of the preceding claims, - wherein the transducer element (12) has a (first) thickness di2, in particular not less than 0.5 mm and / or not more than 2 mm, measured at a temperature of 20°C as maximum expansion in the direction of a normal from its first contact surface, and the shim element (133) has a (second) thickness di33, in particular not less than 1 mm and / or not more than 10 mm, measured at a temperature of 20°C as maximum expansion in the direction of the normal of the first contact surface of the transducer element; - and wherein the transducer element and the shim element are designed such that an expansion difference ratio A0C21 / A0C31 (of the sensor), measured as a ratio of a difference between a (linear) coefficient of thermal expansion a.2 (of the material) of the transducer element (12) and a (linear) coefficient of thermal expansion ai (of the material) of the connecting sleeve (113) to a difference between a (linear) coefficient of thermal expansion < / .3 (des Materials) des Beilagelements (133) und dem (linearen) Wärmeausdehnungskoeffizienten a1 (des Materials) der Anschlußhülse (113), insb. zumindest innerhalb eines zwischen -10°C und 250°C liegenden Temperaturbereichs, eine von einem (Feinabstimmungs-)Parameter ki abhängige Bedingung: fulfilled, where the (fine-tuning) parameter ki is not less than 0.5 and not greater than 1.5, in particular greater than 0.7 and / or less than 1.

2.

6. Sensor according to the previous claim, wherein the (thickness) ratio diss / di 2 of the thickness di33 of the lining element (133) to the thickness di2 of the transducer element (12) is more than 0.5 and less than 7, in particular not less than 2 and / or not more than 4.

7. Sensor according to any of the preceding claims, - wherein the fastening means is a, in particular annular, spherical disc (134), in particular made of a metal and / or of a temperature range not less than 16 • 10 ® K within a temperature range between -10°C and 250°C 1 and / or not more than 17 • 10 ® K 1 material having a (linear) coefficient of thermal expansion a4; - and wherein the ball disc (134) is positioned between screw sleeve (132) and washer element (133).

8. Sensor according to the previous claim, - wherein the spherical disc (134) consists at least partially, in particular predominantly or completely, of a metal, in particular a stainless steel or a nickel-based alloy; and / or - wherein a (linear) coefficient of thermal expansion a4 (of the material) of the spherical disk differs from a (linear) coefficient of thermal expansion a1 (of the material) of the connecting sleeve (1 13) by less than 2 - 10 ® K' at least within a temperature range between -10°C and 250°C 1 and / or deviates by less than 10% of the coefficient of thermal expansion a1 (of the material) of the connecting sleeve (1 13).

9. Sensor according to any of the preceding claims, - wherein the converter element (12) and the deformation body (1 1 1 ) are not materially bonded to each other; and / or - wherein the converter element (12) and the shim element (133) are not materially bonded to each other; and / or - wherein the converter element (12) electrically contacts the deformation body (1 1 1) and / or the connecting sleeve (1 13).

10. Sensor according to any of the preceding claims, - wherein the fastening means include an insulating washer (135), in particular annular, made of a ceramic and / or a plastic and / or of a material with a temperature range not less than 30 • 10 ® K within a range between -10°C and 250°C 1 and / or not more than 50 • 10 ® K' 1 material having a (linear) coefficient of thermal expansion a5; - and wherein the insulating washer (135) is positioned between the converter element (12) and the shim element (133).

11. Sensor according to the previous claim, - wherein the insulating washer (135) is at least partially, in particular predominantly or completely, made of a material that is in particular highly temperature resistant and / or of a material with a temperature range of at least 20 • 10 ® K within a range between -10°C and 250°C 1 and / or not more than 40 • 10 ® K 1 consisting of a plastic, in particular a polyimide (Kapton), exhibiting a (linear) coefficient of thermal expansion a5; and / or - wherein a (linear) coefficient of thermal expansion a5 (of the material) of the insulating washer differs from a (linear) coefficient of thermal expansion a2 (of the material) of the shim element (133) by less than 20 • 10 ® K at least within a temperature range between -10°C and 250°C 1 and / or deviates by less than 50% of the (linear) coefficient of thermal expansion a2 (of the material) of the shim element (133); and / or - wherein the insulating disc (135) has a (third) thickness d3, measured at a temperature of 20°C as maximum expansion in the direction of the normal of the first contact surface of the transducer element (12), which thickness d3 is not less than 0.05 mm and / or not more than 0.5 mm.

12. Sensor according to one of the preceding claims, further comprising: a sensor flag (112) extending from the first surface (111+) of the deformation body, in particular rod-shaped, plate-shaped or wedge-shaped.

13. Sensor according to the previous claim, - wherein the deformation body and sensor flag are materially bonded to each other, in particular welded or soldered together; and / or - wherein the deformation body and sensor flag, in particular the connecting sleeve (113), deformation body and sensor flag, are components of one and the same monolithic molded part; and / or - wherein the sensor flag consists at least partially, in particular predominantly or completely, of a metal, in particular a stainless steel or a nickel-based alloy; and / or - wherein the deformation body and sensor flag, in particular the connecting sleeve (113), deformation body and sensor flag, are made of the same material; and / or - wherein the electrical sensor signal (of the transducer element) represents time-changing, in particular at least temporarily periodic, movements of the sensor flag.

14. Sensor according to any one of claims 12 to 13, further comprising: a compensating body extending from the second surface of the deformation body, in particular rod-shaped, plate-shaped or sleeve-shaped, for compensating forces and / or moments resulting from joint movements of the deformation body and the sensor flag.

15. Sensor according to the previous claim, - wherein the compensating body extends through the shim, in particular such that a principal axis of inertia (in particular a longitudinal axis) of the compensating body and a principal axis of inertia (in particular a longitudinal axis) of the shim are parallel to each other, in particular coincident, and / or such that the shim and the compensating body do not contact each other; and / or - wherein the deformation body and the compensation body are materially bonded to each other, in particular welded or soldered together; and / or - wherein the sensor flag and the compensating body are arranged in alignment with each other; and / or - wherein the compensating body and the deformation body are positioned and aligned with each other such that a principal axis of inertia of the deformation body extends parallel to a principal axis of inertia of the compensating body, in particular coincides with it; and / or - wherein the deformation body and the compensating body are components of one and the same monolithic molded part, in particular such that the sensor flag, deformation body and compensating body and / or that the connecting sleeve, deformation body and compensating body are components of the same molded part; and / or - wherein the compensating body consists at least partially, in particular predominantly or completely, of a metal, in particular a stainless steel or a nickel-based alloy; and / or - wherein the deformation body and the compensating body are made of the same material, in particular such that the sensor flag, deformation body and compensating body and / or the connecting sleeve, deformation body and compensating body are made of the same material.

16. Measuring system for measuring at least one flow parameter, in particular a flow velocity and / or a volumetric flow rate, of a fluid flowing in a pipeline, which measuring system comprises: - a sensor (1) according to one of the preceding claims, in particular for detecting pressure fluctuations in the flowing fluid; - and measuring electronics (2) electrically connected to the transducer element of the sensor, which is designed to receive and process the sensor signal from the sensor, in particular to generate measured values ​​(XM) representing at least one flow parameter, and / or to feed an electrical driver signal into the transducer element, in particular to generate a force that causes deformation of the deformation body.

17. Measuring system according to the preceding claim, further comprising: a pipe (3) with a lumen (3') which can be inserted into the course of the same pipeline and which is designed to guide the fluid flowing in the pipeline, wherein the sensor (1) is inserted into the same pipe, such that the first surface of the deformation body (111) faces the lumen (3') of the pipe and that the sensor flag projects into the same lumen.

18. Measuring system according to claim 16, further comprising: a pipe (3) with a lumen (3') that can be inserted into the course of said pipeline and is designed to guide the fluid flowing in the pipeline, - wherein an opening (3") is formed in the wall of the tube (3), in particular having a socket (3a) serving to hold the deformation body (111) on the wall, - and wherein the sensor (1) is inserted into the same opening (3"), such that the deformation body (111) covers the opening (20'), in particular, hermetically seals it and / or that the first surface of the deformation body (111) faces the lumen (3') of the tube.

19. Measuring system according to the preceding claim, comprising a sensor according to one of claims 14 to 15, - with the sensor flag protruding into the lumen of the tube - and wherein the sensor flag (112) has a length, measured as the minimum distance between a proximal end of the sensor flag (112) bordering the deformation body (111) and a distal end of the sensor flag (112) away from the deformation body (111) or its surface (111+), which length is less than 95% of a caliber (DN) of the pipe (3) and / or more than half of that caliber (DN).

20. Measuring system according to one of claims 16 to 20, further comprising: a baffle body (4) arranged in the lumen of the tube (3), in particular upstream, namely in the (main) flow direction upstream of the sensor, which is designed to create a Kärmännian vortex street in the flowing fluid.

21. Measuring system according to the preceding claim, wherein the sensor is suitably arranged for detecting pressure fluctuations caused by a Kärmännian vortex street established within the flowing fluid.

22. Using a measuring system according to one of claims 16 to 21 for measuring a flow parameter - in particular a flow velocity and / or a volumetric flow rate and / or a mass flow rate - of a fluid flowing in a pipeline, in particular at least temporarily at a temperature of more than 200°C and / or at least temporarily at a pressure of more than 100 bar acting on the deformation body and / or the sensor flag of the sensor, in particular a steam.

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