WO2020001875A1

WO2020001875A1 - Temperature calibrator

Info

Publication number: WO2020001875A1
Application number: PCT/EP2019/063409
Authority: WO
Inventors: Christian Peuker; Marc Schalles; Pavo Vrdoljak
Original assignee: Endress+Hauser Wetzer Gmbh+Co. Kg
Priority date: 2018-06-26
Filing date: 2019-05-23
Publication date: 2020-01-02
Also published as: DE102018115286A1

Abstract

The invention relates to a calibrating apparatus (1) for calibrating at least one measurement apparatus (2) for determining and/or monitoring the temperature of a medium, comprising - a calibrator block (7) having at least one cavity (8) for receiving the at least one measurement apparatus (2) to be calibrated and - a heating/control unit (9) which is arranged and designed to heat the calibrator block (7) to a definable calibration temperature (T_K). According to the invention, at least one thermally conductive coupling unit (10) is provided, said coupling unit (10) being designed and insertable into the cavity (8) such that at least one partial region (T) of an inner volume (V) of the cavity (8) is enclosed at least in part by the coupling unit (10), and said coupling unit (10) being designed to ensure uniform heat distribution at least in the partial region (T).

Description

Temperature calibrator

The invention relates to a calibration device for calibrating at least one measuring device for determining and / or monitoring the temperature of a medium. The measuring device is, for example, a thermometer, or a temperature determination unit of a thermal flow measuring device, or a temperature switch.

Thermometers, thermal flow meters and temperature switches are known per se from the prior art. For the sake of simplicity and without restricting generality, the following description refers exclusively to thermometers. However, the considerations can be applied to thermal

Transfer flowmeters and temperature switches.

Thermometers in a wide variety of configurations have become known from the prior art. There are thermometers that use the expansion of a liquid, a gas or a solid with a known expansion coefficient to measure the temperature, or those that relate the electrical conductivity of a material or a quantity derived from it to temperature, such as that electrical resistance at

Use of resistance elements or the thermoelectric effect in the case of thermocouples. In contrast, radiation thermometers, especially pyrometers, use the thermal radiation of a substance to determine its temperature. The respective underlying measurement principles are available in a variety of

Publications have been described.

In the case of a temperature sensor in the form of a so-called thin-film sensor, in particular a resistance temperature detector (RTD), there is, for example, one provided with connecting wires and applied to a carrier substrate

Sensor element used, the back of the carrier substrate is usually coated with metal. So-called sensor elements are used

Resistance elements, which are provided for example by platinum elements, are used, which are also commercially available under the names PT10, PT100, and PT1000, among others.

In the case of temperature sensors in the form of thermocouples, in turn, the temperature is determined by a thermal voltage that arises from different materials between the thermowires connected on one side. Thermocouples according to DIN standard IEC584, eg thermocouples, are usually used for temperature measurement of type K, J, N, S, R, B, T or E, used as a temperature sensor. However, other material pairs, in particular those with a measurable Seebeck effect, are also possible.

Calibration of the thermometers is required for many areas of application. A calibration is generally understood as a determination of the extent to which an output variable of a measuring device corresponds to the true value of the respective process variable.

For the calibration of thermometers, so-called calibration baths and so-called block calibrators, for example, have become known from the prior art. In these calibrations, a comparative calibration is usually carried out, in which a thermometer to be calibrated is compared with a reference thermometer with regard to its respective output variable and the value for the temperature derived therefrom. In this regard, for example, the book “Technische

Temperature measurement ”by Frank Bernhard, 2nd edition, 2014, published in Springer-

Verlag Berlin Heidelberg, Chapter 7: Calibration of touch thermometers referenced.

Calibration baths usually provide a higher accuracy with regard to the

Calibration achievable. A disadvantage of such a calibration device, however, is that the liquids used for the calibration partially evaporate, or may also have chemical influences on the thermometers to be calibrated. In addition, calibration facilities in the form of calibration baths are only for limited

Temperature ranges usable and also not mobile. The mentioned disadvantages of calibration baths can be overcome by using a calibration device in the form of block calibrators. A block calibrator comprises a calibrator block in the form of a solid, which can be heated to a predeterminable calibration temperature by means of a heating / control unit. At least two cavities are arranged in the calibration block, which are used to hold a reference thermometer and the at least one thermometer to be calibrated. The

Cavities are often designed in the form of bores and the calibrator block is made of a thermally conductive material, for example a metal or a ceramic. Both block calibrators have become known, in which the

Reference thermometer is fixed, as well as those in which the reference thermometer can be detachably arranged. To calibrate the one to be calibrated

A thermometer is then compared, for example, to an output variable of the thermometer with the temperature of the calibrator block determined by the reference thermometer.

A disadvantage of calibration devices in the form of block calibrators, however, is that they generally have a lower accuracy than a calibration bath with regard to calibration. One of the reasons for this is that an exact temperature measurement in solids is difficult. In particular, various measurement errors can occur, some of which are listed below as examples:

Compared to a liquid, such as those used in calibration baths, a solid occurs, in particular, due to heat being given off to one

Larger stationary and non-stationary around the calibration block

Temperature gradients.

The thermal coupling between that arranged in the cavity

Thermometer and the calibration block is dependent, among other things, on the mechanical coupling between the calibration block and the thermometer; In particular, air gaps between the calibration block and the thermometer in the state arranged in the cavity play a decisive role in this regard.

Since different thermometers to be calibrated have different structures, for example with regard to the arrangement of the

Sensor element within the thermometer, the respective thermal coupling also varies. Thus, at the same temperature of the calibrator block, different values for the temperature determined by means of the thermometer to be calibrated can occur.

In order to enable the most accurate possible calibration of the thermometer to be calibrated, it is of fundamental importance that the reference thermometer and the thermometer to be calibrated are each exposed to the same temperature. Here, among other things, the thermal contacts between the calibration block and the reference thermometer and the thermal contacts between the calibration block and the thermometer to be calibrated play a role

decisive role. It takes place between the calibrator block and the

Reference thermometer or between the calibrator block and the thermometer to be calibrated in each case an exchange of heat until there is a thermal

Sets balance. Only when there is thermal equilibrium in each of the cavities, or for the reference thermometer and the one to be calibrated

Thermometer each a constant temperature. It is also of crucial importance that the same temperature prevails in each of the cavities or for each of the measuring devices introduced into the calibrator block, that is to say that the reference thermometer and the thermometer to be calibrated essentially have the same temperature have the same temperature. This temperature is referred to below as the equilibrium temperature. Until this equilibrium is reached, heat spreads or conducts within the calibrator block and between the calibrator block and the respective measuring devices. In this context, heat dissipation or heat conduction becomes a Heat flow understood in any direction, in particular this includes both a heat flow from the calibrator block to at least one of the thermometers, corresponding to the case that the calibrator block has a higher temperature than the respective thermometer, and also in the opposite direction, in the event that the calibrator block has a lower temperature, understood.

The time that elapses until a thermal equilibrium is reached after a temperature change DT basically depends on the structure of the block calibrator, on the thermal conductivities of the materials used and on the thermal contacts, for example between the calibrator block and the respective one

Thermometer, or between the heating / control unit and the calibrator block.

It is therefore the object of the present invention to provide a block calibrator with increased accuracy with regard to the calibration of the one to be calibrated

To provide thermometers.

This object is achieved by comprising a calibration device for calibrating at least one measuring device for determining and / or monitoring the temperature of a medium

a calibrator block with at least one cavity for receiving the at least one measuring device to be calibrated, and

a heating / control unit, which is arranged and configured to heat the calibrator block to a predeterminable calibration temperature. According to the invention, at least one thermally conductive coupling unit is also provided, the coupling unit being designed and insertable into the cavity in such a way that at least a portion of an inner volume of the cavity is at least partially surrounded by the coupling unit, and

which coupling unit is designed to ensure homogeneous heat distribution at least in the partial area.

If the temperature of the calibrator block changes, in particular during calibration, heat conduction or heat spreading takes place within the calibrator block and, if a measuring device is located in a cavity, between the calibrator block and the Measuring device instead. In order to ensure the most accurate possible calibration of the measuring device, it is therefore of great importance that the heat is homogeneous in the entire calibrator block and within the cavity or cavities in which the measuring device (s) can be inserted , spreads. In this context, any air gaps or material transitions may represent disadvantageous thermal resistances. Since air gaps and

Material transitions can also be different in different cavities, and moreover, even if a measuring device is introduced several times into the same cavity, it cannot always be guaranteed that several measuring devices placed in a calibrator block are each exposed to the same temperature at the same temperature of the calibrator block, or that a measuring device is exposed to the same temperature each time at the same temperature of the calibrator block during successive calibrations in the same cavity. The coupling unit according to the invention now advantageously ensures a homogeneous

Heat distribution at least within the sub-area. Accordingly, it ensures, in particular, homogeneous heat conduction and, consequently, homogeneous

Temperature distribution, in particular an essentially constant temperature, at least in the partial area at least partially surrounded by the coupling unit. In this way, the accuracy with regard to calibration of at least one measuring device can be significantly increased. In addition, any waiting times, which are until the establishment of a thermal equilibrium within the calibrator block with measuring devices arranged in the cavities, are shorter.

As already mentioned, the measuring device is, for example, a thermometer or a temperature determination unit of a thermal

Flow meter, or a temperature switch. The measuring device comprises at least one temperature-sensitive sensor element, for example a temperature sensor, in particular in the form of a resistance element or a thermocouple. The coupling unit is designed and arranged such that it at least partially surrounds the sensor element when the measuring device is installed.

The solution according to the invention serves to overcome the problems described with regard to block calibrators and, consequently, the achievable measurement accuracy. By using a coupling unit according to the invention, good thermal coupling, that is to say good thermal contact, can be ensured between the measuring device and the calibrator block. In particular, depending on the configuration, it can be ensured that there is no air gap between an outer wall of the measuring insert and an inner wall of the immersion body. In addition to thermal coupling, mechanical coupling can also be guaranteed.

Numerous possibilities are conceivable for the design of the coupling unit, all of which come under the present invention. The exact design depends, among other things, on various specifications regarding the measuring device, that is to say also on the particular geometric situation. Selected, particularly preferred configurations are described below. It goes without saying that the different configurations can also be combined with one another. In one embodiment, the coupling unit is at least partially on an inner one

Wall of the cavity attached or fastened. The coupling unit is thus arranged between the inner wall of the cavity and the outer wall of the measuring device when it is inserted into the cavity. In this case, the measuring device can in particular be removed from the cavity without having to remove the coupling element.

In a further embodiment, the coupling unit is configured to one

to ensure mechanical and / or thermal coupling between the calibrator block, in particular in the region of the cavity, and the measuring device in the state arranged in the cavity. A mechanical coupling can in particular reduce or avoid air gaps that may occur. In addition, any thermal resistances due to material changes have less variance. Differences in temperature in different cavities, or in the case of several calibrations of a measuring device in the same cavity, are thus significantly reduced.

In another embodiment, the coupling unit is designed and / or arranged in such a way that it at least partially surrounds the measuring device when the measuring device is arranged in the cavity, in particular the coupling unit is arranged in such a way that it is in the state in the cavity Measuring device at least partially surrounds at least part of the measuring device, in which a sensor element of the measuring device is arranged. However, several coupling units can also be provided, in particular if the measuring device has several sensor elements arranged at several positions. In connection with thermometers, the latter case involves so-called multipoint thermometers, which are known per se from the prior art. It is also possible for a single coupling unit to be designed and / or arranged such that a coupling unit at least partially surrounds a plurality of sensor elements of the measuring device when the measuring device is arranged in the cavity.

A particularly preferred embodiment includes that the coupling unit comprises a solid lubricant, in particular graphite, boron nitride, copper or brass, or the coupling unit in the form of a powder, in the form of a coating, or in the form of a solid body, preferably in the form of a film or in the form of a tubular body, in particular a sleeve.

It has become known from the prior art to use so-called thermal pastes to improve thermal contacts between two objects. However, these have the disadvantage that the respective thermal contact cannot be reproduced well and the quality of the contact is not constant, for example due to progressive corrosion. Solid lubricants have the advantage that they can be arranged more easily and, above all, precisely and reproducibly. They are also particularly suitable for compensating shape tolerances. A reproducible thermal contact between the immersion body and the measuring insert can thus be achieved.

In one embodiment of the coupling unit in the form of a powder, the powder can, for example, be introduced into the cavity before the measuring device is arranged in the cavity. In the case of a coating, this can in turn

For example, be arranged on an inner wall of the cavity. The same applies to the design in the form of a solid body. The body can, for example, be dimensioned such that, when the measuring device is installed, it is arranged in the cavity, in particular with an exact fit, in an intermediate space in which an air gap would otherwise form. It is therefore adapted to the dimensions of the cavity and / or the measuring device.

Another particularly preferred embodiment of the calibration device includes that the coupling unit comprises at least one material with anisotropic thermal conductivity. The thermal conductivity of the coupling unit depends on the direction. For example, a thermal conductivity can be greater in a first plane than in a second plane, which runs perpendicular to the first plane. Thus, the heat conduction through the

Coupling unit can be advantageously influenced in a targeted manner by a design of the coupling unit that may be specially designed for a specific application. For example, it can be achieved that, as a result of a temperature change in the calibrator block, there is first a circumferential distribution of the heat in the area of the coupling unit before it propagates from the coupling unit into a volume of the partial area and thus to the measuring device. In this regard, it is advantageous if the coupling unit is arranged and / or configured in such a way that, parallel to at least one inner wall of the cavity, it has a higher, in particular at least 10 times larger, in particular at least 30 times higher, thermal conductivity than perpendicular to the inner wall. A particularly preferred embodiment includes that the coupling unit is designed to ensure that a temperature at least in the partial area of the inner volume of the cavity, which partial area at least partially from the

Coupling unit is surrounded, is essentially constant. Furthermore, the temperatures in the partial area and those of the calibrator block are then advantageously the same. A further preferred embodiment includes that the coupling unit is designed such that it enables, in particular reversible, movement of the measuring device relative to the cavity, in particular in the axial direction. Usually, different materials, in particular with different coefficients of thermal expansion, are used for the measuring device and the calibrator block. As a result of temperature changes in the medium, there are in particular different expansions, in particular in the longitudinal direction of the cavity. The coupling unit is then preferably designed such that it compensates for the different, in particular reversible, expansions due to changes in the temperature, in particular in the longitudinal direction. In this way, a constant thermal contact between the cavity and the measuring device can be ensured regardless of the temperature.

It is also advantageous if at least one fastening means is provided for fastening the coupling unit. In this regard, the fastener can be a separate component. However, it is also possible for the fastening means to be part of the calibration device and in particular arranged in the cavity and / or part of the measuring device.

In this regard, various configurations are also conceivable, of which some preferred variants are given below:

For example, an embodiment comprises that an inner wall of the cavity has a shoulder and / or a projection which serves as a fastening means, an inner diameter of the cavity being variable along a longitudinal axis of the cavity.

In the case of a shoulder, for example, the inner diameter in an end region of the cavity can be larger than in the region of the opening, which is in the region of the

Surface of the calibrator block. In the case of a projection, it is advantageous if the inside diameter of the cavity is smaller in the region of the projection than in other regions. If the measuring device is removed from the cavity, these configurations automatically prevent the coupling unit from moving in the axial direction through the shoulder or through the projection in the inner wall of the cavity.

A further embodiment provides that the fastening means is a, in particular mechanical, fitting connection, in particular where that

Fastening means has at least one snap ring or a fitting ring.

Furthermore, the fastening means can be an adhesive. Finally, a further embodiment includes that the fastening means is at least partially made of a sintered material.

Another preferred embodiment includes that the calibration device comprises at least one thermally conductive coupling element, which coupling element between at least a partial area of the heating / control unit and a partial area of the

Calibrator block is arranged, and which coupling element is used to ensure a homogeneous heat distribution at least in the partial area of the calibrator block. The coupling element can be configured analogously to the at least one coupling unit in at least one of the embodiments described. However, it is not arranged in a cavity of the calibrator block, but rather is arranged between a partial area of the heating / control unit and a partial area of the calibrator block. In this way, the coupling element ensures a homogeneous heat distribution, in particular from the control / heating unit to the calibrator block.

It should be pointed out that in the context of the present application the two previously unpublished German patent applications with the file number

1020181 1 1 167.3 and 102017100267.7. The teaching described there in connection with a device for determining and / or monitoring at least one process variable or with a device for determining and / or monitoring the temperature of a medium can also be applied analogously to a calibration device according to the invention.

The invention is illustrated by the following drawings. It shows:

1: a block calibrator and two measuring devices in the form of thermometers according to the prior art,

2: a schematic view for a calibration device with a coupling unit in a first embodiment,

3: a second embodiment of a calibration device according to the invention with a coupling unit, in which the coupling unit is fastened within the cavity of the calibrator body, and

Fig. 4 shows a third embodiment of a calibration device according to the invention with a coupling element arranged between the heating / control unit and the calibrator block.

In the figures, the same elements are identified by the same reference symbols. 1 shows a schematic illustration of a calibration device 1 according to the prior art. The calibration device 1 comprises a calibrator block 7 with four cavities 8, into each of which a measuring device 2 can be inserted. The measuring devices 2 for determining the temperature of a medium shown by way of example in FIG. 1 are each a thermometer. A heating / control unit 9 is arranged below the calibrator block 7, by means of which the calibrator block 7 can be heated to a predeterminable calibration temperature TK. It should be pointed out that the heating control unit 7 does not necessarily have to be arranged below the calibrator block 7. Rather, all configurations and arrangements known to the person skilled in the art from the prior art in connection with block calibrators 1 for a heating / control unit 9 are conceivable. There are also many

Design options for the calibrator block 7. All of these possible

Refinements also fall under the present invention. It should also be noted that the reference measuring device 2 'can be detachably or permanently arranged within one of the cavities 8 of the calibration device 1.

The calibration device 1 can also have a computing unit [not shown], by means of which a comparison can be made using a reference measuring device

2 'measured temperature can be compared with a temperature measured by means of the measuring device 2 to be calibrated. On the basis of the comparison, the measuring device 2 to be calibrated can then be calibrated, for example by establishing a functional relationship between an output variable of the measuring device 2 on the basis of the comparison of those using the measuring devices 2 and 2 ′

Temperatures is adjusted.

The two measuring devices 2 and 2 'shown are each a thermometer with a measuring insert 3 or 3' and electronics 4 or 4 'according to the prior art. Within the measuring insert 3 or 3 'there is a sensor element 5 or

5 ', which in the present case is a temperature sensor in the form of a resistance element, which makes electrical contact via the connecting lines 6 or 6' and is connected to the electronics 4 or 4 '. In other configurations, the electronics 4 or 4 'can also be arranged separately from the measuring insert 3 or 3'. Also, the sensor element 5 or 5 'need not necessarily be one

Act resistance element, or the number of connecting lines 6 or 6 'used does not necessarily have to be two. Rather, depending on

applied measuring principle a different number of connecting wires 6 or

6 'can be used. However, it is advantageous if the reference measuring device 2 'and the measuring device 2 to be calibrated are configured identically. As already explained, the accuracy of the calibration using a block calibrator 1, as illustrated in FIG. 1, depends on many different factors. The various possible problems already described can, however, be overcome by using a calibration device 1 according to the invention with a coupling unit 10, as has also already been explained.

Numerous possibilities are conceivable for the configuration of the coupling unit 10, of which some preferred configurations are described below by way of example. The exact configuration depends, among other things, on various specifications, in particular with regard to the measuring device 2 to be calibrated, that is to say also from the particular geometric situation.

2 shows a schematic sectional illustration of a cavity 8 of a calibrator block 7 of a calibration device 1 with a measuring device 2, which is also shown schematically and is introduced into the inner volume V of the cavity 8. The measuring device 2 from FIG. 2 is here as an example for one of the measuring devices 2 introduced into the calibration device 1, and can be both a reference measuring device 2 or 2 ′ to be calibrated. The calibration device 1 comprises a coupling unit 10 according to the invention, which is arranged in the partial area T of the inner volume V of the cavity 8, in which partial area T the sensor element 5 is located when the measuring device 2 is installed. Furthermore, the coupling unit 10 is arranged between an inner wall of the cavity 8 and an outer wall of the measuring device 2, here the measuring insert 3. For example, it can be attached directly to the inner wall of the cavity 8.

The coupling unit 10 causes a thermal and depending on the design of the

Coupling unit 10 also a mechanical coupling between the calibrator block 7 and the measuring device 2. The coupling unit 10 thus serves to improve the thermal conductivity within the calibrator block 7 or between the

Calibrator block 7, represented by the wall of the cavity 8 and the measuring device 2. This significantly increases the accuracy with regard to calibration of the measuring device to be calibrated.

The coupling unit 10 preferably comprises a solid lubricant, in particular graphite, boron nitride, copper, or brass. There are several for the exact design

Variants conceivable. For example, the coupling unit 10 can be configured in the form of a powder, in the form of a coating, or as a solid body. It is also possible for the coupling unit 10 to comprise at least one material with anisotropic thermal conductivity. In other configurations, such as the one shown in FIG. 3, both

Embodiments, at least one fastening means 11 for fastening the coupling unit 10 in a predeterminable position relative to the cavity 8 or to the measuring device 2 is also provided. In this regard, in addition to the configurations shown in FIG. 3, many other possibilities are conceivable and familiar to the person skilled in the art, which also fall under the present invention.

In the two configurations shown, the fastening means 11 is in each case part of the cavity 8. In other configurations, not shown here, this can be done

Fastening means 1 1, however, can also be designed as a separate unit, or as part of the measuring device 2.

According to the configuration according to FIG. 3a, the inner wall of the cavity 8 has a shoulder which serves as a fastening means 11. As a result, the inner diameter di of the immersion body 2 in a first partial area Ti is smaller than the inner diameter d ₂ in a second partial area T ₂ , which second partial area T ₂ corresponds to the partial area T in which the coupling unit 10 is arranged. Paragraph 11 ensures that the coupling unit 10 is fixed in the partial area T = T ₂ , in particular when the measuring device 2 moves axially along the longitudinal axis L of the cavity.

3b shows a second possible embodiment of the fastening means 11. Here, the inner wall of the cavity 8 has a projection. The inside diameter d _{3 of} the cavity 8 is reduced in the area of the projection 11 compared to the inside diameter in the remaining area of the cavity 8. In the partial areas T1 and T2 arranged on both sides of the projection, the inner diameter can be the same or different. The projection 11 can also be arranged in the upper region of the cavity 8, in particular in such a way that it is arranged in the region of the surface of the calibrator blocks 7 which has the opening of the cavity 8. In the case of FIG. 3b, the fastening means 1T in particular prevents an axial movement of the coupling unit 10, for example in the event that the measuring device 2 is removed from the cavity 8 or is introduced into the cavity 8.

In a further embodiment, which is outlined in FIG. 4, the calibration device 1 further comprises a coupling element 10a. The coupling element 10a is arranged between the heating / control unit (9) and the calibrator block 7

and serves to ensure a homogeneous heat distribution within the calibrator block 7. In the present embodiment, the coupling element 10a is configured such that it is arranged along the entire contact area between the calibrator block 7 and the heating / control unit 9. However, the coupling element does not necessarily have to run along the entire contact area. It can also be extend along a portion of the contact surface or beyond the contact surface between the rain heating unit 9 and the calibrator block 7.

The coupling element 10a is preferably adapted to the respective heating / control unit 9. It goes without saying that for other configurations of the heating / control unit 9, the coupling element 10a can also be configured differently.

4, coupling units are also introduced into the cavities 8 of the calibrator block 7. However, these are not visible in the illustration shown.

LIST OF REFERENCE NUMBERS

1 calibration device

2 measuring device

3 measuring insert

4 electronics

5 sensor element

6 connecting wires

7 calibrator block

8 cavity

9 control / heating unit

10 coupling unit

1 1 fasteners

T, Ti, T ₂ partial area of the cavity di, d _2, d ₃ internal diameter of the cavity L longitudinal axis of the cavity V internal volume of the cavity

Claims

claims

1 . Calibration device (1) for calibrating at least one measuring device (2) for determining and / or monitoring the temperature of a medium comprising

a calibrator block (7) with at least one cavity (8) for receiving the at least one measuring device (2) to be calibrated, and

a heating / control unit (9) which is arranged and configured to heat the calibrator block (7) to a predeterminable calibration temperature (TK),

characterized,

that at least one thermally conductive coupling unit (10) is provided, which coupling unit (10) is designed and can be inserted into the cavity (8) such that at least a partial area (T) of an inner volume (V) of the cavity (8) is at least partially from the Coupling unit (10) is surrounded, and

which coupling unit (10) is designed to ensure homogeneous heat distribution at least in the partial area (T).

2. calibration device (1) according to claim 1,

wherein the coupling unit (10) is at least partially attached or fastened to an inner wall of the cavity (8).

3. calibration device (1) according to claim 1 or 2,

the coupling unit (10) being designed to provide a mechanical and / or thermal coupling between the calibrator block (7), in particular in the

To ensure area of the cavity (8), and the measuring device (2) in the state arranged in the cavity (8).

4. calibration device (1) according to at least one of the preceding claims,

the coupling unit (10) being designed and / or arranged in such a way that, when the measuring device 2 is in the cavity (8), it at least partially surrounds the measuring device, in particular the coupling unit (10) being arranged in such a way that it at least partially surrounds in the state of the measuring device (2) arranged in the cavity (8) at least part of the measuring device (2), in which a sensor element (5) of the measuring device (2) is arranged.

5. calibration device (1) according to at least one of the preceding claims,

wherein the coupling unit (10) comprises a solid lubricant, in particular graphite, boron nitride, copper, or brass, or wherein the coupling unit (10) in Form of a powder, in the form of a coating, or in the form of a solid body, preferably in the form of a film or in the form of a tubular body, in particular a sleeve.

6. calibration device (1) according to at least one of the preceding claims,

wherein the coupling unit (10) at least one material with anisotropic

Includes thermal conductivity.

7. calibration device (1) according to claim 6,

wherein the coupling unit (10) is arranged and / or configured such that, parallel to at least one inner wall of the cavity (8), it has a higher, in particular at least 10 times larger, in particular at least 30 times higher, thermal conductivity than perpendicular to the inner wall.

8. calibration device (1) according to at least one of the preceding claims,

wherein the coupling unit (10) is designed to ensure that a temperature at least in the partial region (T) of the inner volume (V) of the cavity (8), which partial region (T) is at least partially surrounded by the coupling unit (10), in the Is essentially constant.

9. calibration device (1) according to at least one of the preceding claims,

wherein the coupling unit (10) is designed and / or arranged in such a way that it enables, in particular reversible, movement of the measuring device (2) relative to the cavity (8), in particular in the axial direction.

10. calibration device (1) according to at least one of the preceding claims,

at least one fastening means (11) being provided for fastening the coupling unit (10).

1 1. calibration device (1) according to claim 1 1,

wherein an inner wall of the cavity (8) has a shoulder and / or a projection, which serves as fastening means (1 1, 1 T), an inner diameter (di-d ₃ ) of the cavity (8) along a longitudinal axis (L) of the Cavity (8) is variable.

12. Calibration device (1) according to claim 1 1,

the fastening means (1 1) being one, in particular

mechanical, passport connection, in particular where

Fastening means (1 1) has at least one snap ring or a fitting ring.

13. calibration device (1) according to claim 10,

the fastener (1 1) being an adhesive.

14. Calibration device (1) according to claim 1 1,

wherein the fastening means (1 1) is at least partially made of a sintered material.

15. Calibration device (1) according to at least one of the preceding claims, comprising at least one thermally conductive coupling element (10a), the coupling element (10a) between at least a partial area of the heating / control unit (9) and a partial area of the calibrator Blocks (7) is arranged, and which coupling element (10a) serves to ensure a homogeneous heat distribution at least in the partial area of the calibrator block (7).