WO2013000739A1 - Élément sensible capacitif pour détecter un déplacement comprenant plusieurs paires d'électrodes et procédé pour faire fonctionner cet élément - Google Patents

Élément sensible capacitif pour détecter un déplacement comprenant plusieurs paires d'électrodes et procédé pour faire fonctionner cet élément Download PDF

Info

Publication number
WO2013000739A1
WO2013000739A1 PCT/EP2012/061476 EP2012061476W WO2013000739A1 WO 2013000739 A1 WO2013000739 A1 WO 2013000739A1 EP 2012061476 W EP2012061476 W EP 2012061476W WO 2013000739 A1 WO2013000739 A1 WO 2013000739A1
Authority
WO
WIPO (PCT)
Prior art keywords
capacitor
capacitor electrodes
electrodes
displacement
sensor element
Prior art date
Application number
PCT/EP2012/061476
Other languages
German (de)
English (en)
Inventor
Daniel Reznik
Arno Steckenborn
Oliver Theile
Original Assignee
Siemens Aktiengesellschaft
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Publication of WO2013000739A1 publication Critical patent/WO2013000739A1/fr

Links

Classifications

    • 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
    • G01B7/003—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring position, not involving coordinate determination
    • 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
    • G01B7/30—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring angles or tapers; for testing the alignment of axes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/125—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by capacitive pick-up

Definitions

  • Capacitive sensor element for detecting a displacement with a plurality of electrode pairs and method for its operation
  • the invention relates to a capacitive sensor element for De ⁇ tetation a displacement, comprising a plurality of Elektrodenpaa ⁇ r.
  • Such capacitive sensor elements are basically be ⁇ known.
  • the capacitor electrodes are arranged opposite each individually or in groups, wherein a measure ⁇ de shift causes the capacitor electric shift ⁇ relative to each other in parallel.
  • a diaphragm with an aperture or more apertures, which is located in the capacitor gap and is displaced by the displacement to be measured.
  • the effective capacitor area ie the area which, independently of the area of the capacitor electrode , changes, so that an electric field can form, changes.
  • the effective capacitor area is reduced compared to the theoretically maximum possible capacitor area.
  • This change in the effective capacitor area leads to a change in the capacitance C of the capacitor, wherein this change in capacitance when a known voltage U is applied to the capacitor electrodes can be calculated by measuring the charge shift AQ.
  • the charge shift can be determined by measuring the current I flowing between the capacitor plates over the time t.
  • the calculation of the charge shift AQ behaves the following equation.
  • ⁇ Displacement distance to be measured at right angles to the length dimension of the capacitor electrodes. If a shift to the capacitive sensor element are de- tektiert, it can inherently determined by change in capacitance only the length of the displacement path ⁇ the. However, it is not possible to determine an absolute position between the capacitor plates. Therefore, the sensor must be calibrated prior to the start of a measurement so that a position of the capacitor plates with respect to a starting position before the measurement is known. This can be done, for example, by the capacitor plates are brought outside any overlap or the panel is completely pushed between the capacitor plates, so that the electric field collapses. However, he ⁇ the necessary calibration sword intake of reco ⁇ th.
  • the object of the invention is therefore to specify a capacitive sensor element for the detection of displacements, during which measurements are performed at least in a specific measuring position during the measurements. area a starting position of the shift can be determined.
  • the capacitive sensor element for detecting a shift comprises the following components.
  • a multiplicity of first capacitor electrodes are provided, which are connected electrically in parallel.
  • a plurality of second capacitor electrodes is provided, which are also electrically connected in parallel, wherein each of the first capacitor ⁇ electrodes one of the second capacitor electrodes to form electrode pairs is assigned such that between the first capacitor electrodes and the second capacitor electrodes each provided a capacitor gap is.
  • the sensor element has a voltage source between the first capacitor electrodes and the second capacitor electrodes. This can provide a periodically variable voltage with variable period duration, wherein the first capacitor electrodes and / or the second capacitor electrodes are designed as bar oscillators, each having a different natural frequency.
  • first capacitor electrodes are arranged relative to the second capacitor electrodes in such a way that, depending on the displacement to be measured, the second capacitor electrodes are relatively movable relative to the first capacitor electrodes and the effective capacitor area is variable while the width of the capacitor gap remains constant.
  • the ⁇ An arrangement is further selected so that, depending on the amount of displacement to be measured, a different number of
  • Pair of electrodes is involved in the formation of the effective capacitor area.
  • ⁇ the measuring principle be realized.
  • the first capacitor electrodes or the second capacitor electrodes are designed as a beam oscillator with different natural frequency, these bar vibrators are excited only by the variable voltage with variable period to oscillate when they already form a capacitor with the other capacitor electrode by covering the capacitor electrodes.
  • Such an electrode pair is excited to vibrate can be determined in various ways. Particularly preferred is a measurement of the electrical properties of the capacitor pairs , which constantly change their capacity, for example, by ⁇ guided oscillations of the beam oscillator.
  • a measurement of the electrical properties of the capacitor pairs which constantly change their capacity, for example, by ⁇ guided oscillations of the beam oscillator.
  • other read-out methods are conceivable, for example an optical read-out method, by aligning an optical sensor with the oscillating beam oscillator.
  • First capacitor electrodes are always mentioned in the context of this invention if they are those capacitor electrodes which in each case form one side of the capacitors formed by the electrode pairs.
  • the respective second capacitor electrodes are those which are opposite to the first capacitor electrodes, respectively. Is used in the context of this invention only by capacitor Electrodes talk, so are always meant both the first capacitor electrodes and the second capacitor electrodes.
  • the type of periodically variable voltage can be chosen differently. For example, a sinusoidal Perio ⁇ denver running conceivable. Another possibility is to use a square-wave voltage so that the vibrations of the beam oscillators are generated by pulse excitations.
  • the first capacitor electrodes are arranged on a first carrier and the second capacitor electrodes on a second carrier, such that all capacitor gate electrodes form the tines of a comb-like structure, wherein these structures are arranged interlocked and the capacitor gaps are each formed between those adjacent tines that are closest to each other. So that the respective electrode pairs too
  • Form electrode pair is less (capacitor gap), as the distance between the tines each to the other of the two neighboring tines, ie those tines, which forms a capacitor together with the next prong on the support in question. Otherwise, the introduction of electrical force into the tines would always be symmetrical and no vibration would be able to be excited.
  • the shift can be realized by the two combs past each other.
  • This embodiment of the capacitor electrodes has the advantage that a comparatively space-saving design of the sensor element is ent ⁇ .
  • a further advantageous embodiment of the invention is obtained when the first capacitor electrodes are formed as a beam oscillator, which are fixed to a carrier and the second capacitor electrodes are formed on the surface of a substrate, wherein the displacement is parallel to the surface of the substrate.
  • the substrate can be produced by simple structuring of the surface of this substrate.
  • the capacitor electrodes of the electrode pairs successively engage with each other as the displacement progresses gaps of different sizes between the capacitor electrodes can be selected.
  • Ver ⁇ displacement is an angular displacement or linear displacement. Designs for the measurement of a linear displacement have already been described. If an angular displacement is to be measured, then a rotatable system is to be provided.
  • the beam oscillators start from the center of rotation and can, for example, form the first capacitor electrodes.
  • the second capacitor electrodes are then, for example, provided on a substrate, above which can be twisted the bending vibrator.
  • the voltage source can also provide a DC voltage available.
  • the DC voltage can be used to determine a relative displacement between the first capacitor electrodes and the second capacitor electrodes, as already described above.
  • the invention relates to a method for operating a sensor element, which is constructed in the manner already described. Such a method is already known from the prior art, as already described above .
  • the method is characterized in that a shift is detected by relatively moving the second capacitor electrodes to the first capacitor electrodes, depending on the displacement to be measured, and changing the effective capacitor area while keeping the capacitor gap constant. Moreover, involved a different number of electrode pairs in the formation of the effective capacitor area from ⁇ dependent on the amount of displacement to be measured. The number of electrode pairs involved in the formation is determined by changing the period of the voltage, in such a way that all natural frequencies of the second beam oscillators are eventually excited to oscillate.
  • the beam oscillators can, as already explained, be formed by the first capacitor electrodes and / or the second capacitor electrodes.
  • the measuring method according to the invention makes it possible to determine the number of flexural vibrators which are already excited to vibrate, this being the case only when this bar vibrator is already in engagement with the associated other capacitor electrode and in this way forms a capacitor. It can also be said that this particular pair of electrodes is involved in the formation of the effective capacitor area.
  • capacitor area is referred to, which is provided by the whole of the first capacitor electrode and the second capacitor electrodes as the amount of overlap. This can advantageously range from 0 to the total area of the first capacitor electrodes or second capacitor electrodes.
  • the second capacitor electrodes oscillating in the resonant frequency are determined by examining the change in capacitance of the electrode pairs for changes in the respective resonant frequencies. This investigation is advantageous very easy to carry out, since the electrode pairs must be contacted anyway for the excitation of vibrations.
  • the vibrations of the bending beam creates a variable gap width between see the activated electrode pairs, so that the capacitance of these electrode pairs changes periodically. From the periodicity of this change pattern can be determined by measuring the capacitance of all capacitor electrodes, which of the pairs of electrodes are already involved in the formation of the effective capacitor area. This in turn makes it possible to conclude the absolute displacement in the manner according to the invention.
  • a relative displacement of the capacitor electrodes is determined by applying a direct voltage to the first capacitor electrodes and second capacitor electrodes and determining the change in capacitance during a displacement.
  • This value will not change periodically, special countries in a manner known to the displacement law, the law may for example be linear (pe ⁇ -periodic components of the measurement are not taken into account).
  • This is therefore an analog readout method. ren, which allows a stepless determination of the relative change ⁇ tion.
  • a digital readout method is provided by the invention according to ⁇ rain of the electrode pairs, which provides certain absolute bases in the measuring range, ie the measurable displacement range.
  • FIG. 1 is a schematic side view of an exemplary embodiment of the sensor arrangement according to the invention with comb-like design of the capacitor electrodes as a side view;
  • FIG. 2 shows the amplitude A of a capacitance change of the effective capacitor area due to oscillations of the bar oscillators as a function of the excitation frequency of the voltage f
  • FIG. 3 shows the relationship between a change in the capacitance C of the effective capacitor area as a function of a
  • FIG. 4 schematically shows another exemplary embodiment of the sensor arrangement according to the invention, in which the beam oscillators are guided past capacitor electrodes which are mounted on a substrate and
  • FIG. 5 schematically shows a further exemplary embodiment of the sensor arrangement according to the invention for determining an angular displacement.
  • a sensor arrangement according to FIG. 1 consists of a first carrier 11, on which comb capacitor-like tines first capacitor electrodes 12 are fastened.
  • a second carrier 13 on which second condenser electrodes 14 are similarly arranged in the manner of prongs of a comb.
  • the carrier 13 may advance with the tips of the tines in one
  • Direction x perform a lateral displacement 15, resulting in a relative movement between the first capacitor electrodes 12 and the second capacitor electrodes 14 results.
  • the first capacitor electrodes 12 are all the same length, while the second capacitor electrodes 14 are staggered like organ pipes, i. H. their length increases in the manner shown from left to right. This is indicated by dash-dotted lines 16.
  • FIG. 2 illustrates how a frequency f of a sinusoidal AC voltage, which is applied in a manner not shown to the parallelly connected first electrodes 12 and second electrodes 14 connected in parallel, is tuned becomes.
  • the first capacitor electrodes are
  • the second capacitor electrodes 14 are produced on a substrate 21 and form a conductive coating on the insulating surface of the substrate 21.
  • a contact is shown schematically, wherein also a voltage source 22 is provided which is both a DC voltage can provide as well as one of these superimposed periodically variable voltage whose periodicity, ie period duration, is changeable.
  • the first capacitor electrodes 12 and the second capacitor electrodes 14 are shown separated from one another. In reality, the first capacitor electrodes, which can be displaced in lateral displacement direction 15, have to pass over the second capacitor electrodes. The observer therefore has to imagine the first capacitor electrodes offset by 1.2 times the length of the bending oscillator to the right.
  • the first capacitor electrodes 12 successively overlap with the second capacitor electrodes 14.
  • the lowermost capacitor electrode 12 is about to engage the lowermost capacitor electrode 14 in the drawing.
  • the overlying first capacitor electrodes come in a displacement as indicated by x lr x 2 and X3 for engagement. This is in each case the displacement x, in which the corresponding pairs of electrodes begin to participate in the formation of the effective capacitor area and therefore can also be excited to lateral vibrations.
  • the oscillations of the capacitor electrodes 1 according to FIG. 4 are made perpendicular to the plane of the drawing.
  • the different stiffnesses, and thus different resonant frequencies, the capacitor electrodes 12 according to Figure 4 is not determined by their different lengths as shown in Figure 1, but by ih re ⁇ different width.
  • the carrier 20 is rotatably mounted about a rotation axis 24, wherein the first capacitor electrodes 12 of different lengths protrude like a beam from the carrier.
  • the second con- are densatorelektroden 14 shown as pads and be painted in ⁇ be voted angles. This makes it possible to determine an absolute position of the angle.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Gyroscopes (AREA)

Abstract

L'invention concerne un élément sensible capacitif pour détecter un déplacement x, ainsi qu'un procédé pour faire fonctionner cet élément. Selon l'invention, cet élément sensible capacitif se compose d'une pluralité d'électrodes de condensateur (12) qui forment des paires d'électrodes (17). Les électrodes de condensateur sont configurées de sorte qu'une augmentation de la course de déplacement x entraîne une augmentation du nombre de paires d'électrodes formées les unes à la suite des autres, ce qui contribue à l'augmentation de la surface effective de condensateur. Selon l'invention, les paires d'électrodes déjà formées peuvent être mises en vibration, les paires d'électrodes vibrant avec une fréquence propre caractéristique. Les paires d'électrodes vibrantes peuvent ainsi être identifiées et la position x absolue peut être déduite. De façon avantageuse, un étalonnage du système par rapport à une position zéro de x devient ainsi superflu.
PCT/EP2012/061476 2011-06-29 2012-06-15 Élément sensible capacitif pour détecter un déplacement comprenant plusieurs paires d'électrodes et procédé pour faire fonctionner cet élément WO2013000739A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE201110078355 DE102011078355B3 (de) 2011-06-29 2011-06-29 Kapazitives Sensorelement zur Detektion einer Verschiebung mit mehreren Elektrodenpaaren und Verfahren zu dessen Betrieb
DE102011078355.5 2011-06-29

Publications (1)

Publication Number Publication Date
WO2013000739A1 true WO2013000739A1 (fr) 2013-01-03

Family

ID=46319761

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2012/061476 WO2013000739A1 (fr) 2011-06-29 2012-06-15 Élément sensible capacitif pour détecter un déplacement comprenant plusieurs paires d'électrodes et procédé pour faire fonctionner cet élément

Country Status (2)

Country Link
DE (1) DE102011078355B3 (fr)
WO (1) WO2013000739A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113008128B (zh) * 2019-12-19 2023-12-19 通用技术集团国测时栅科技有限公司 一种电容式角位移传感器及其转子

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5025346A (en) * 1989-02-17 1991-06-18 Regents Of The University Of California Laterally driven resonant microstructures
DE19808549A1 (de) * 1998-02-28 1999-09-02 Bosch Gmbh Robert Mikromechanische Kammstruktur
DE10255578A1 (de) * 2002-11-28 2004-06-09 Valeo Wischersysteme Gmbh Vorrichtung und Verfahren zur kapazitiven Bestimmung des Drehwinkels und der Drehgeschwindigkeit einer Welle eines Motors

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10046059A1 (de) * 2000-09-18 2002-03-28 Oskar Bschorr Flachlautsprecher
DE102008057280A1 (de) * 2008-11-14 2010-05-27 Northrop Grumman Litef Gmbh Corioliskreisel, Einrichtung für einen Corioliskreisel und Verfahren zum Betrieb eines Corioliskreisels
DE102009045696B4 (de) * 2009-10-14 2021-06-02 Robert Bosch Gmbh Verfahren zur kapazitiven Erfassung einer mechanischen Auslenkung

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5025346A (en) * 1989-02-17 1991-06-18 Regents Of The University Of California Laterally driven resonant microstructures
DE19808549A1 (de) * 1998-02-28 1999-09-02 Bosch Gmbh Robert Mikromechanische Kammstruktur
DE10255578A1 (de) * 2002-11-28 2004-06-09 Valeo Wischersysteme Gmbh Vorrichtung und Verfahren zur kapazitiven Bestimmung des Drehwinkels und der Drehgeschwindigkeit einer Welle eines Motors

Also Published As

Publication number Publication date
DE102011078355B3 (de) 2012-10-11

Similar Documents

Publication Publication Date Title
DE102010029645B4 (de) Mikromechanisches Bauelement mit einer Teststruktur zur Bestimmung der Schichtdicke einer Abstandsschicht und Verfahren zum Herstellen einer solchen Teststruktur
DE102005005554B4 (de) Verfahren zur Überprüfung eines Halbleitersensors für eine dynamische Grösse
EP0924518B1 (fr) Appareil pour la mesure de caractéristiques d'un produit textile
EP3227162B1 (fr) Système de capteurs pour volant, volant avec un tel système et procécé pour opérer un tel système
DE102004043259B4 (de) Dynamischer Halbleitersensor mit variablem Kondensator auf laminiertem Substrat
DE10013424A1 (de) Filter für elektrische Signale
DE102013217111A1 (de) Mikromechanisches Bauteil und Verfahren zur Herstellung eines mikromechanischen Bauteils
WO2009077263A1 (fr) Capteur de vitesse de rotation et son procédé de fonctionnement
DE102013212059B4 (de) Mikromechanischer Inertialsensor
DE2224497B2 (de) Wandler zur Umwandlung eines elektrischen Signals in eine akustische Oberflächenwelle
DE4433679C2 (de) Schwingungserreger
DE112018000491T5 (de) Sensorelement, Winkelgeschwindigkeitssensor und Multiaxialwinkelgeschwindigkeitssensor
WO2013000739A1 (fr) Élément sensible capacitif pour détecter un déplacement comprenant plusieurs paires d'électrodes et procédé pour faire fonctionner cet élément
DE19950355C2 (de) Beschleunigungssensor und Beschleunigungserfassungsgerät
DE102005010393B4 (de) Halbleitersensor zur Erfassung einer dynamischen Grösse
DE19754093C2 (de) Kapazitive Meßeinrichtung zur Feststellung des Füllstandes eines Behälters
WO1998011443A1 (fr) Detecteur pour capter de façon capacitive une acceleration
EP3312574B1 (fr) Détecteur de vibration avec détection de température intégrée
DE3320546C2 (de) Kapazitiver Aufnehmer zum Messen der Flüssigkeitsmenge in einem Behälter
DE4226430C2 (de) Kapazitiver Beschleunigungssensor
DE3004331C2 (de) Zu Dickenscherungsschwingungen anregbare Resonatorplatte
DE102006059929A1 (de) Inertialsensor mit einer seismischen Masse
DE102011081014B4 (de) Mikromechanisches Bauteil und Herstellungsverfahren für ein mikromechanisches Bauteil
DE3727440A1 (de) Schieblehre
DE3916959A1 (de) Messaufnehmer zur beruehrungslosen messung von drehmomenten an rotierenden wellen

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12728259

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12728259

Country of ref document: EP

Kind code of ref document: A1