Abstract
The invention relates to an apparatus for determining and/or monitoring a temperature of a medium in a containment, comprising a measuring insert having a temperature sensor for registering temperature, a protective tube, in which the temperature sensor is arranged, and a heat conductive, formed piece, which is arranged in the protective tube and surrounds the measuring insert at least sectionally.
Claims
1-15. (canceled)
16. An apparatus for determining or monitoring a temperature of a medium in a containment, comprising: a measuring insert having a temperature sensor for registering temperature; a protective tube, in which the temperature sensor is arranged; and a heat conductive, formed piece, which is arranged in the protective tube and surrounds the measuring insert at least sectionally.
17. The apparatus as claimed in claim 16, wherein the formed piece is made of copper, silver, graphite, boron nitride, a steel, or an alloy containing at least one of these materials.
18. The apparatus as claimed in claim 16, wherein the formed piece is at least sectionally tubular, especially cylindrical.
19. The apparatus as claimed in claim 16, wherein the formed piece is pot shaped.
20. The apparatus as claimed in claim 19, wherein a floor of the formed piece has a bore, along which the measuring insert is guidable.
21. The apparatus as claimed in claim 16, wherein the formed piece has at least sectionally a geometry corresponding to a geometry of the protective tube or the measuring insert.
22. The apparatus as claimed in claim 16, wherein the formed piece includes an endpiece, whose outer diameter is greater than an outer diameter of the formed piece in a middle region of the formed piece.
23. The apparatus as claimed in claim 22, wherein the endpiece is disc shaped.
24. The apparatus as claimed in claim 22, wherein a geometry of the endpiece at least partially corresponds to a geometry of the protective tube in a region, into which the formed piece is introducible.
25. The apparatus as claimed in claim 16, further comprising a securement component for securing of the formed piece in the protective tube or on the measuring insert.
26. The apparatus as claimed in claim 25, wherein the securement component is embodied and arranged in such a manner that by using the securement component a compressive force is exertable on the formed piece.
27. The apparatus as claimed in claim 25, wherein the securement component has at least one basic body, which is arrangeable around the formed piece in the protective tube.
28. The apparatus as claimed in claim 27, wherein the basic body is formed of a plastic.
29. The apparatus as claimed in claim 27, wherein the securement component has at least one spring, by which the predeterminable compressive force is suppliable using the basic body.
30. The apparatus as claimed in claim 16, wherein the temperature sensor comprises at least one resistance element or thermocouple.
Description
[0030] The invention will now be explained in greater detail based on the appended drawing. The figures of the drawing show as follows:
[0031] FIG. 1 a thermometer for invasive temperature measurement having a protective tube according to the state of the art;
[0032] FIG. 2 a thermometer for noninvasive temperature measurement according to the state of the art;
[0033] FIG. 3 a first embodiment for a thermometer of the invention for noninvasive temperature determination with a formed piece of the invention;
[0034] FIG. 4 by way of example, embodiments for a formed piece of the invention;
[0035] FIG. 5 a second embodiment for a thermometer of the invention for invasive temperature determination with a formed piece of the invention; and
[0036] FIG. 6 a formed piece of the invention with an embodiment of the securement means.
[0037] In the figures, equal elements are provided with equal reference characters.
[0038] Shown in FIG. 1 is a schematic view of a thermometer 1 according to the state of the art for registering the temperature T of a pipeline 2 flowed through by a medium M. Thermometer 1 is introduced into the pipeline 2 by means of a protective tube 3. The temperature sensor 5 is part of a measuring insert 4, which is introducible releasably into the protective tube 3. In the case of an assembly of this type, the achievable accuracy of measurement depends, among other things, on the heat drain W to the environment of the process. The undesired heat drain grows with sinking penetration depth of the protective tube 3 into the pipeline 2, such that precisely for pipelines 2 of small diameter an increased measurement error is to be reckoned with.
[0039] A comparable problem results also for the case of a noninvasive temperature determination, such as shown in FIG. 2. In this case, the thermometer 1 does not protrude into the pipeline 2, but, instead, rests externally on a wall 2a of the pipeline 2. Also in such case, the measuring insert 3 includes a temperature sensor 5. Shown for the thermometer 1 of FIG. 2 are, furthermore, connection lines 6a, 6b, by means of which the temperature sensor 5 is connectable with an electronics 7. While the shown thermometer 1 is embodied with compact construction with integrated electronics 7, in the case of other thermometers 1 the electronics 7 can also be arranged separately from the measuring insert 3. The temperature sensor 5 can comprise, for example, a resistance element or a thermocouple and, depending on embodiment of the temperature sensor 5, the number of used connection lines 6 can vary. Also in such case, an undesired heat drain W to the environment takes place, which degrades the accuracy of measurement of the thermometer 1.
[0040] In order to reduce the negative influence of the heat drain, a thermometer of the invention includes a formed piece 8, which is arranged in the protective tube 3 and at least sectionally surrounds the measuring insert 4. Formed piece 8 is, thus, arranged at least partially between the measuring insert 4 and the protective tube 3.
[0041] A first embodiment of an apparatus 1 of the invention with a formed piece of the invention is shown in FIG. 3. The apparatus is a noninvasive thermometer 1 similar to the thermometer 1 of FIG. 2. Formed piece 8 for this embodiment is pot shaped. In a section, which for the embodiment shown here is arranged in the region of a floor F of the formed piece 8, the formed piece 8 is arranged between the measuring insert 4 and a floor of the protective tube 3, and the wall 2a of the container.
[0042] The formed piece 3 serves to provide a, preferably uniform, heating of a volume V surrounding the temperature sensor 5 and for preventing undesired temperature gradients in the region of the temperature sensor 5 due to heat loss to the environment.
[0043] Shown in FIG. 4 are three possible preferred embodiments for a formed piece 8 of the invention, which all and likewise the formed piece shown in FIG. 3, can be applied both for an invasive as well as also for a noninvasive thermometer. Formed piece 8 of FIG. 4a is tube or pipe shaped. The shown variant has a circularly round, cross sectional area; however, also other cross sectional areas are possible and fall within the scope of the invention. Formed piece 8 can in an additional embodiment not separately shown, however, similar to that shown in FIG. 3, furthermore, have a floor F. Furthermore, arranged in this floor F can be a bore, through which the measuring insert is guidable. The bore has then a diameter, especially a diameter fitting the diameter of the measuring insert 4 and less than an outer diameter of the formed piece 8. The outer diameter of the formed piece 8 is, in turn, fitted, for example, at least in the tubular section to an inner diameter of the protective tube 3. In an end region E, the geometry of the formed piece 8 can, furthermore, be fitted to the geometry of the measuring insert 4 and/or of the protective tube 3.
[0044] Another embodiment for a formed piece 8 of the invention is show in FIG. 4b. In such case, the formed piece 8 likewise includes a cylindrical section. Moreover, the formed piece 8 has an endpiece 9, whose outer diameter d.sub.9 is greater than an outer diameter ds of a middle region of the formed piece 8. Endpiece 9 is disc shaped in the illustrated embodiment. In such case, endpiece 9 further includes an optional bore, as a result of which measuring insert 3 is guidable. Also the formed piece 8 shown in FIG. 4c includes a tubular section and an endpiece 9. Endpiece 9 is, however, adapted to the geometry of the protective tube 3, or embodied corresponding to such geometry, in contrast to FIG. 4b.
[0045] Another example of an embodiment of an apparatus 1 of the invention is shown in FIG. 5. Involved in such case is a thermometer 1 for invasive temperature determination, similarly to the thermometer 1 of FIG. 1. Thermometer 1 includes a formed piece 8 embodied analogously to the formed piece 8 of FIG. 4c. Formed piece 8 is arranged in the protective tube 3 and sectionally surrounds the measuring insert 4. Protective tube 3 has a variable inner diameter. In a first region B.sub.1, it has a smaller inner diameter than in a second region B.sub.2. Endpiece 9 of the formed piece 8 is arranged in a transition between the first region B1 and the second region B2 of the protective tube 3 and arranged corresponding to the geometry of the protective tube in the transition region. Endpiece 9 has therewith virtually the function of a lid, which seals the volume V surrounding the temperature sensor 5 from the environment. The formed piece 8 serves to conduct heat, which flows via the protective tube 3 to the environment, to the temperature sensor 5. In this way, a uniform temperature distribution around the temperature sensor 5 can be assured and an undesired heat drain W to the environment of the process prevented.
[0046] In order to assure a best possible thermal contact between the formed piece 9 and the protective tube 3, and measuring insert 4, the apparatus 1 of FIG. 5 includes supplementally, optionally, securement means 10. It is to be noted here that all embodiments shown here for thermometer 1 of the invention can optionally utilize suitable securement means 10 and according to the invention all securement means 10 known to those skilled in the art are possible.
[0047] The securement means of FIG. 5 comprises a cylindrical basic body 11, which is arranged at least sectionally around the formed piece 8 in the protective tube 3, and a spring 12 to exert a predeterminable compressive force on the formed piece. For transmitting the compressive force of the spring 12, the basic body 11 includes a shoulder 13, on which the spring 12 is arranged.
[0048] A more detailed view of such arrangement is shown in FIG. 6. In the view shown in FIG. 5, basic body 11 serves, furthermore, for thermal insulation of the formed piece 8 from the environment. For this, the basic body 11 is made, by way of example, of a heat insulating material and is so arranged that it surrounds the cylindrical section of the formed piece.
LIST OF REFERENCE CHARACTERS
[0049] 1 apparatus [0050] 2 containment; 2a wall of the containment [0051] 3 protective tube [0052] 4 measuring insert [0053] 5 temperature sensor [0054] 6 connection wires [0055] 7 electronics [0056] 8 formed piece [0057] 9 endpiece [0058] 10 securement means [0059] 11 basic body [0060] 12 spring [0061] 13 shoulder of the basic body [0062] M medium [0063] T temperature [0064] W heat drain [0065] d diameter [0066] B.sub.1, B.sub.2 regions [0067] V volume surrounding the temperature sensor [0068] F floor of the formed piece
