DE8631978U1 - Sensor coil - Google Patents
Sensor coilInfo
- Publication number
- DE8631978U1 DE8631978U1 DE19868631978 DE8631978U DE8631978U1 DE 8631978 U1 DE8631978 U1 DE 8631978U1 DE 19868631978 DE19868631978 DE 19868631978 DE 8631978 U DE8631978 U DE 8631978U DE 8631978 U1 DE8631978 U1 DE 8631978U1
- Authority
- DE
- Germany
- Prior art keywords
- sensor
- winding
- sensor according
- inductance
- impedance converter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000004804 winding Methods 0.000 claims description 18
- 239000000463 material Substances 0.000 claims description 8
- 230000001939 inductive effect Effects 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 4
- 230000006978 adaptation Effects 0.000 claims description 2
- 244000309464 bull Species 0.000 claims description 2
- 238000000034 method Methods 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 239000000110 cooling liquid Substances 0.000 claims 1
- 230000005855 radiation Effects 0.000 description 6
- 238000013459 approach Methods 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000004870 electrical engineering Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
- G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
- G01D5/20—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature
- G01D5/2006—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the self-induction of one or more coils
- G01D5/202—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the self-induction of one or more coils by movable a non-ferromagnetic conductive element
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness
- G01B7/023—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness for measuring distance between sensor and object
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D3/00—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups
- G01D3/028—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups mitigating undesired influences, e.g. temperature, pressure
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K13/00—Thermometers specially adapted for specific purposes
- G01K13/02—Thermometers specially adapted for specific purposes for measuring temperature of moving fluids or granular materials capable of flow
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/945—Proximity switches
- H03K17/95—Proximity switches using a magnetic detector
- H03K17/9505—Constructional details
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/945—Proximity switches
- H03K17/95—Proximity switches using a magnetic detector
- H03K17/952—Proximity switches using a magnetic detector using inductive coils
- H03K17/9537—Proximity switches using a magnetic detector using inductive coils in a resonant circuit
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Description
Die Erfindung betrifft einen induktiven Sensor, der unter harten, industriellen Umweltbedingungen, insbesondere hohen Umgebungsund /oder Strahlungstemperaturen arbeitet.The invention relates to an inductive sensor that operates under harsh, industrial environmental conditions, in particular high ambient and/or radiation temperatures.
Induktive Sensoren werden für die unterschiedlichsten Schalt- und Mess-Aufgaben in der Industrie eingesetzt. Dieser Einsatz erfolgt dabei überwiegend bei Raumtemperatur und Betätigungsabständen von einigen Millimetern.Inductive sensors are used for a wide variety of switching and measuring tasks in industry. They are mainly used at room temperature and at actuation distances of a few millimeters.
In der Schwerindustrie gibt es jedoch auch Aufgaben für induktive Sensoren, die einen Wirkbereich von über 10 cm benötigen. Zur Lösung derartiger Aufgaben werden Anordnungen verwand, bei denen eine gros-sf lach ige Sensorspule und die dazugehörige Auswerteelektronik räumlich von einander getrennt angeordnet werden.In heavy industry, however, there are also tasks for inductive sensors that require an effective range of more than 10 cm. To solve such tasks, arrangements are used in which a large-area sensor coil and the associated evaluation electronics are arranged spatially separated from one another.
Diese Sensorspule ist die Induktivität eines Schwingkreises, der bei Annäherung von Metall durch in diesem Metall induzierte Wirbelströme bedämpft wird und die^e Dämpfung wird in einer Folgeschaltung in das gewünschte Signal umgesetzt.This sensor coil is the inductance of an oscillating circuit which is dampened by eddy currents induced in metal when it approaches it, and this damping is converted into the desired signal in a subsequent circuit.
Bei den hier infragestehenden grossflächigen Sensorspulen ist die Arbeitefrequenz wesentlich niedriger, als bei kleinen induktiven Näherungsschaltern. _/a weiterhin zur Optimierung des gewünschten Effektes ein möglichst grosses L/C-Verhältnis gefordert wird, ergeban sich hieraus ..!eist Spulen mit einigen hundert Windungen, wobei dann die Formgebung dieser Spule den gegebenen Aufgaben angepasst wird.The operating frequency of the large-area sensor coils in question here is significantly lower than that of small inductive proximity switches. Furthermore, to optimize the desired effect, the largest possible L/C ratio is required, which usually results in coils with several hundred turns, with the shape of this coil being adapted to the given tasks.
Der Wickelkörper wird aus Gründen der mechanischen Stabilität nach Fertigstellung in ein geeignetes Gehäuse eingebaut und anschliessend meist mit Giessharz ausgegossen, um eine ausreichende mechanische Stabilität zu erhalten.For reasons of mechanical stability, the winding body is installed in a suitable housing after completion and is then usually filled with casting resin in order to achieve sufficient mechanical stability.
Eine Sonderausführung der vorbeschriebenen Sensorspul en stellen wassergekühlte Sensorspulen dar, die dort zum Einsatz kommen, wo das zu detektierende Material so hohe Temperaturen aufweist, dass die Sensorspule ohne geeignete Kühlung durch die Hitzeeinwirkung des zu detektierenaen Materials zerstört würde.A special version of the sensor coils described above are water-cooled sensor coils, which are used where the material to be detected has such high temperatures that the sensor coil would be destroyed by the heat of the material to be detected without suitable cooling.
Bekannte Sensorspulen der vorbeschriebenen Art bestehen aus mehrlaqiqen Spulen der ersten Art, die zusätzlich noch durch einen qeeigneten Wassermantel gekühlt werden. Dieser Wassermantel wird zumeist durch einen mit der Sensorspule verbundenem Hohlkörper gebildet, durch den Wasser zur Kühlunq fliesst.Known sensor coils of the type described above consist of multiple coils of the first type, which are additionally cooled by a suitable water jacket. This water jacket is usually formed by a hollow body connected to the sensor coil, through which water flows for cooling.
Die vorbeschriebenen Spulen werden üblicher Weise aus in der Elektrotechnik üblichem lackiertem Kujjferdraht oder Kupferlitze hergestellt. Hierdurch ergibt sich für die Spulen selbst eine sehr begrenzte mechanische Stabil tat und Tempertaturbeiastbarkeit.The coils described above are usually made from lacquered copper wire or copper strands, which are common in electrical engineering. This results in very limited mechanical stability and temperature resistance for the coils themselves.
Alle vorbeschriebenen Sensorspulen erfordern zu ihrer Herstellung einen grossen mechanischen Fertigungsaufwand und werden in Bezug auf Zuverlässigkeit und Robuetheit meist den praktischen Anforderungen nicht gerecht, so dass der Einsatz derartiger Sensoren in der Industrie begrenzt ist.All of the sensor coils described above require a great deal of mechanical manufacturing effort to produce and usually do not meet practical requirements in terms of reliability and robustness, so that the use of such sensors in industry is limited.
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• I I I I I• I I I I I
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Ziel der vorliegenden Erfindung ist es, für die vorbeschriebenen Aufgabenstellungen einfachere und betriebssichere Sensoren zu schaffen, die zusätzlich noch Eigenschaften haben, die die bislang bekannten Sensorspulen nicht besitzen.The aim of the present invention is to create simpler and more reliable sensors for the tasks described above, which additionally have properties that the previously known sensor coils do not have.
Der Grundgedanke der Erfindung ist es, die Induktivität des Sensors so zu gestalten, dass sie ohne zusätzliches Gehäuse eingesetzt werden kann. Dieses lässt sich am besten und einfachsten durch eine Induktivität realisieren, die pur aus einer einzigen Windung besteht. Eine derartige Lösung bietet den wesentlichen Vorteil, dass diese Windung aus sehr stabilen Material hergestellt werden kann, z.B. aus massivem S'. ^b- oder Rohrmaterial, so dass ein mechanischer Schutz der den Sensor bildenden Induktivität nicht erforderlich ist,The basic idea of the invention is to design the inductance of the sensor in such a way that it can be used without an additional housing. This can be achieved best and most easily with an inductance that consists purely of a single winding. Such a solution offers the significant advantage that this winding can be made from very stable material, e.g. from solid steel or tubular material, so that mechanical protection of the inductance forming the sensor is not required.
Die Anpassung der Sensorwindung an einen optimalen SchwingkreisAdaptation of the sensor winding to an optimal oscillating circuit
* erfolgt über einen mit dieser Windung verbundenen* is carried out via a connected to this winding
t Impedanzwandler, durch den auch eine galvanische Trennung der t Impedance converter, which also provides galvanic isolation of the
Ü Sensor-Windung von der übrigen Schaltung erfolgt.Ü Sensor winding from the rest of the circuit.
Ein weiterer Vorteil der beschriebenen Sensoi—Windung ist dieAnother advantage of the described Sensoi winding is the
'< Möglichkeit der einfachen Erdung, ohne die elektrischen'< Possibility of simple earthing without disturbing the electrical
\ Eigenschaften zu beeinflussen und diese Erdung gleichzeitig als \ properties and at the same time use this grounding as
f mechanische Befestigung des Sensors zu gestalten.f mechanical fastening of the sensor.
Der erfindungsgemäss beschriebene Sensor ist elektrisch soThe sensor described according to the invention is electrically
( ; unkritisch und mechanisch so einfach zu erstellen, dass er sogar ( ; uncritical and mechanically so easy to create that it even
&igr;, beim Bau von industriellen Anlagen problemlos vor Ort von &igr;, when building industrial plants, it can be easily installed on site by
' ungelernten Kräften erstellt werden kann. Diese Möglichkeit' unskilled workers. This possibility
:; erlaubt die Lösung industrieller Sensorauf gaben, für die bislang: ; allows the solution of industrial sensor tasks for which previously
' ein wesentlich höherer technischer Aufwand getrieben werden musste, sofern sie überhaupt lösbar waren.' a much higher level of technical effort had to be made, if they could be solved at all.
\ Alle bislang bekannten induktiven Sensoren nutzen die änderung einer Spulengüte durch sich ändernde Wirbelstromverluste aus, wie sie durch Annäherung von Metallteilen gegeben ist. \ All inductive sensors known to date exploit the change in coil quality due to changing eddy current losses, as caused by the approach of metal parts.
Die Spulengüte hängt aber- auch vom elektrischen Wirkwiderstand der Spule ab, der seinerseits bei den hier zum Einsatz kommenden Materialien temperaturabhängig ist. Der wirksame Widerstand befindet sich - verursacht durch den i„kineffekt - in einer oberflächen nahen Schicht der Windung. Diese Oberfläche ist beim Passieren von heissem Material der Strahlung dieses Materials ausgesetzt. Somit reagiert der wirksame ohmsche Widerstand des hier beschriebenen Sensors auch auf Wärmestrahlung. Für die weitere Arbeistsweise des Sensors ist es gleichgültig, wodurch die Änderung der Spul engüt&rgr; erfolgt, ob durch Wirbelstromverluste oder durch einen höheren ohmschen Widerstand.The coil quality also depends on the electrical resistance of the coil, which in turn is temperature-dependent for the materials used here. The effective resistance is located in a layer of the winding close to the surface, caused by the i'kin effect. This surface is exposed to the radiation of hot material when it passes through it. The effective ohmic resistance of the sensor described here therefore also reacts to thermal radiation. For the further operation of the sensor, it is irrelevant how the change in the coil quality occurs, whether through eddy current losses or through a higher ohmic resistance.
Auf Grund des vorbeschriebenen Effektes lassen sich mit dem vorbeschri ebenen Sensor nicht nur alle Sensor-Geräte realisieren, die Annäherung von Metall auf Grund sich ändernder Wirbelstromverluste detektieren, sondern zusätzlich auch noch Sensor-Geräte, die Wärmestrahlung detektieren.Due to the effect described above, the sensor described above can be used not only to implement all sensor devices that detect the approach of metal due to changing eddy current losses, but also to implement sensor devices that detect thermal radiation.
Blatt -3-Sheet -3-
it·· (1it·· (1
Blatt -3-Sheet -3-
AIs Sensor-Berate lassen sich mit einem vorbeschriebenen Sensor
sowohl Berate herstellen, die bei Annäherung von Metallteilen,
aider aber auch bem Auf treffen einer bestimmten Wärmestrahlung,
ein Schaltsignal abgeben, wie aber auch Berate, die bei
Annäherung von Metallteilen abstandsproportional, oder beim
auftreffen von Wärmestrahlung intenstätsprobortional einen
analogen Messwert ausgeben.AIs sensor advisors can be used with a previously described sensor
both produce berats that, when metal parts approach,
but also when a certain heat radiation hits,
give a switching signal, as well as advisors who
Approach of metal parts proportional to distance, or
impact of thermal radiation intensity proportionally a
output analog measured value.
Eine Ausführung des Sensors fur hohe Temperaturen ist besonders f A version of the sensor for high temperatures is particularly suitable for
einfach, da für diesen Fall zweckmässiger Weise die Sensorwindung c simple, since in this case the sensor winding c
als Rohr ausgeführt wird, durch dass ein geeignetes Kühlmittel, [designed as a pipe through which a suitable coolant, [
z.B. Wasser flieset. Ein Ausführungsbeispiel ist in Fig.l ', eg water flows. An example is shown in Fig.l ',
dargestellt. I shown. I
Auf Brund der vorbeschriebenen Arbeitsweise lässt sich der Sensor ^Based on the above-described method of operation, the sensor ^
in rohrförmiger Ausführung auch als Temperatur—Sensor für ein Iin tubular design also as a temperature sensor for an I
durch das Rohr hindurchfliessendes Medium verwenden. $Use medium flowing through the pipe. $
In einer praktischen Ausführung der Erfindung läset sich der 'iIn a practical embodiment of the invention, the 'i
Impedanzwandler sowohl in die Windung mit integrieren, oder aber §Impedance converter can be integrated into the winding or §
auch über eine gesonderte elektrische Leitung mit der Windung *also via a separate electrical cable with the winding *
verbinden. ;■!connect. ;■!
Claims (9)
Sensor—Induktivität infolge von sich ändernden1.) Sensor operating according to an inductive method, in which the quality of the
Sensor inductance due to changing
verändert wird und diese Güteänderung die Signalgrösse des
Sensors darstellt dadurch gekennzeichnet, dass zum Zwecke der
Anpassung an die Erfordernisse der Folgeschaltung die
Sensor-Induktivität mit einem Impedanzwandler verbunden ist.Vortex current losses or in which the quality of the inductance is reduced by the effect of heat and the associated change in resistance
is changed and this quality change the signal size of the
Sensors is characterized in that for the purpose of
Adaptation to the requirements of the subsequent circuit
Sensor inductance is connected to an impedance converter.
Sensor-Induktivität aus nur einer Windung besteht.2.) Sensor according to claim 1, characterized in that the
Sensor inductance consists of only one turn.
durch das die Sensor-Windung bildende Rohr eine Kühlflüssigkeit
f1iesst.5.) Sensor according to claim 1, 2 and 4, characterized in that
through the tube forming the sensor winding a cooling liquid
flows.
wird.7.) Sensor according to claim 1 to 6, characterized in that the sensor winding is electrically grounded at one or more points
becomes.
ausgeführt ist.8.) Sensor according to claim 1 to 7, characterized in that»> the earthing of the sensor winding as a mechanically supporting element
is executed.
der Impedanzwandler über eine gesonderte Leitung mit der
Sensor-Windung verbunden ist.IQ-.) Sensor according to claim 1 to 8, characterized in that
The impedance converter is connected to the
Sensor winding is connected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19868631978 DE8631978U1 (en) | 1986-11-28 | 1986-11-28 | Sensor coil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19868631978 DE8631978U1 (en) | 1986-11-28 | 1986-11-28 | Sensor coil |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE8631978U1 true DE8631978U1 (en) | 1990-03-22 |
Family
ID=6800665
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19868631978 Expired DE8631978U1 (en) | 1986-11-28 | 1986-11-28 | Sensor coil |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE8631978U1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0455613A2 (en) * | 1990-05-03 | 1991-11-06 | Alessandro Dreoni | Inductive proximity sensor and position transducer with a passive scale |
-
1986
- 1986-11-28 DE DE19868631978 patent/DE8631978U1/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0455613A2 (en) * | 1990-05-03 | 1991-11-06 | Alessandro Dreoni | Inductive proximity sensor and position transducer with a passive scale |
| EP0455613A3 (en) * | 1990-05-03 | 1994-02-16 | Alessandro Dreoni |
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