JP2912949B2 - Capacitive pressure sensor - Google Patents
Capacitive pressure sensorInfo
- Publication number
- JP2912949B2 JP2912949B2 JP30271790A JP30271790A JP2912949B2 JP 2912949 B2 JP2912949 B2 JP 2912949B2 JP 30271790 A JP30271790 A JP 30271790A JP 30271790 A JP30271790 A JP 30271790A JP 2912949 B2 JP2912949 B2 JP 2912949B2
- Authority
- JP
- Japan
- Prior art keywords
- joint
- bottom plate
- movable electrode
- electrode
- spacer
- 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 - Fee Related
Links
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明はタンク内の液面位置や配管等の水頭などを測
定するため、流体の圧力変化を静電容量によって検出す
る圧力センサに関する。Description: TECHNICAL FIELD The present invention relates to a pressure sensor that detects a change in pressure of a fluid by capacitance in order to measure a liquid level position in a tank, a head of a pipe, or the like.
〔従来の技術〕 流体圧力の変化を検出するに際して、圧力をダイヤフ
ラムに受けてそのリフト量変化に変え、ダイヤフラムに
結合した可動電極板と、その可動電極板に対向して平行
に配置した固定電極板との間の静電容量の変化として電
気的に検出することがおこなわれている。このような検
出機構を有する従来の静電容量式圧力センサは、たとえ
ば第４図に示すような構造を有しており、ダイヤフラム
支持用底板31とダイヤフラム32間で形成されるダイヤフ
ラム室33内に入口34から圧力を測定する流体を導入す
る。このダイヤフラム32の外周端面側から順に平板状の
底板接合部35、第１立ち上がり部36、波部37、第２立ち
上り部38、中央の最上端に位置する平板状の可動電極板
接合部40からなっている。可動電極板接合部40の上面に
は絶縁体41を介して可動電極板42が固定される。ダイヤ
フラム32の底板接合部35を底板31と共に挾持するように
スペーサ43を立設し、その上部に固定電極板44を固定環
46によって挾持し、可動電極板42と平行になるように固
定している。可動電極板42の周縁部にはリード線47を接
続し、スペーサ43に設けた通孔48を通して外部へ導き、
一方、固定電極板44の一部はスペーサ43の外部に出る端
子部50を形成し、この端子部50に接続したリード線51と
前記リード線47によって、可動電極42と固定電極44とか
らなるコンデンサー52の両端子のリード線を構成する。
また、固定電極44の上面にはPTCヒータ53を設けて結露
を防止している。[Prior Art] When detecting a change in fluid pressure, the pressure is applied to a diaphragm and changed into a change in lift amount, and a movable electrode plate coupled to the diaphragm and a fixed electrode disposed in parallel to the movable electrode plate Electrical detection is performed as a change in capacitance between the plate and the substrate. A conventional capacitance type pressure sensor having such a detection mechanism has a structure as shown in FIG. 4, for example, and is provided in a diaphragm chamber 33 formed between a diaphragm support bottom plate 31 and a diaphragm 32. A fluid whose pressure is to be measured is introduced from the inlet 34. From the outer peripheral end face side of the diaphragm 32, a flat bottom plate joint 35, a first rising portion 36, a wavy portion 37, a second rising portion 38, and a flat movable electrode plate joint 40 located at the uppermost end in the center. Has become. A movable electrode plate 42 is fixed to the upper surface of the movable electrode plate joint 40 via an insulator 41. A spacer 43 is erected so as to sandwich the bottom plate joint 35 of the diaphragm 32 together with the bottom plate 31, and a fixed electrode plate 44 is fixed above the spacer 43.
It is clamped by 46 and fixed so as to be parallel to the movable electrode plate 42. A lead wire 47 is connected to the peripheral portion of the movable electrode plate 42, and guided to the outside through a through hole 48 provided in the spacer 43,
On the other hand, a part of the fixed electrode plate 44 forms a terminal portion 50 that goes out of the spacer 43, and is composed of the movable electrode 42 and the fixed electrode 44 by the lead wire 51 and the lead wire 47 connected to the terminal portion 50. The lead wires of both terminals of the capacitor 52 are formed.
Further, a PTC heater 53 is provided on the upper surface of the fixed electrode 44 to prevent dew condensation.
このような圧力センサにおいて、ダイヤフラム室33内
に導かれる流体の圧力に応じてダイヤフラム32が変形
し、可動電極42が固定電極44に対して近づき、あるいは
遠ざかる。その結果SUS材からなる両電極42,44間の距離
が変化するので、両電極間で蓄えられる電荷の量が変化
する。このようにして両電極42,44からなるコンデンサ5
2の容量が変化するので、このコンデンサを発振回路中
に設け、発振周波数の変化に変換し、更にこれを積分し
て電圧に変えることによりダイヤフラム室33内の流体の
圧力を電圧に変換している。In such a pressure sensor, the diaphragm 32 is deformed in accordance with the pressure of the fluid introduced into the diaphragm chamber 33, and the movable electrode 42 approaches or moves away from the fixed electrode 44. As a result, the distance between the two electrodes 42 and 44 made of the SUS material changes, so that the amount of charge stored between the two electrodes changes. Thus, the capacitor 5 composed of the two electrodes 42, 44
Since the capacity of 2 changes, this capacitor is provided in the oscillation circuit, converted to a change in the oscillation frequency, and further integrated to change into a voltage, thereby converting the pressure of the fluid in the diaphragm chamber 33 to a voltage. I have.
上記従来の静電容量式圧力センサを例えば車両のガソ
リンタンク等のように使用環境が極低温から高温まで巾
広い温度変化を生じ、あるいは大きな振動を生じるもの
に用いると、特に大きな温度変化によって各部材の熱膨
脹差が大きく、測定値に誤差を生ずることとなる。特に
その影響が大きい部分はスペーサ43の部分であり、スペ
ーサ43の底板31との基端から固定電極44支持部との高さ
H4が高い程その熱膨脹する長さが大きくなるため、可動
電極42と固定電極44との距離ｄが大きくなり、熱膨脹の
影響が測定値の大きな誤差となって表れる。When the above-mentioned conventional capacitance type pressure sensor is used for a device in which the use environment causes a wide temperature change from a very low temperature to a high temperature, such as a gasoline tank of a vehicle, or generates a large vibration, the temperature change is particularly large due to a large temperature change. The difference in thermal expansion of the member is large, causing an error in the measured value. The portion where the influence is particularly large is the portion of the spacer 43, and the height from the base end of the spacer 43 to the bottom plate 31 and the height of the fixed electrode 44 supporting portion.
Since the length of H 4 is the thermal expansion higher increases, the distance d between the movable electrode 42 and the fixed electrode 44 becomes large, it appears the influence of thermal expansion becomes a large error of measurement.
また、両電極42,44はSUS材からなるため重量が大きく
なり、特に可動電極42の重量は絶縁材41及びダイヤフラ
ム32との接合部の強度に影響するため、その重量による
繰り返し荷重によって接合部が破損することがあった。In addition, since both electrodes 42 and 44 are made of SUS material, the weight is large. Particularly, the weight of movable electrode 42 affects the strength of the joint with insulating material 41 and diaphragm 32. Could be damaged.
本発明は上記従来のものの欠点を解消するため、流体
を導入する開口を備えた底板の上面中央に凹所を設け、
底板の外周上部にスペーサを立設し、底板の外周上部と
スペーサとの間にダイヤフラムの外周縁に形成した底板
接合部を挟持し、ダイヤフラムの底板接合部と中央の可
動電極接合部との間に波部を備え、可動電極接合部には
支持部材を介してセラミック素材の表面に電極層を形成
した可動電極を固定し、セラミック素材の片側に電極層
を形成し他側にヒータ層を形成した固定電極を前記可動
電極に対向してスペーサ上に固定し、前記底板の外周上
部から固定電極までの高さを小さくし、それにより環境
に影響されない静電容量式圧力センサとしたものであ
る。The present invention provides a recess at the center of the upper surface of a bottom plate provided with an opening for introducing a fluid, in order to solve the above-mentioned drawbacks of the conventional device,
A spacer is erected on the outer peripheral upper part of the bottom plate, and the bottom plate joint formed on the outer peripheral edge of the diaphragm is sandwiched between the outer peripheral upper part of the bottom plate and the spacer, and between the bottom plate joint of the diaphragm and the central movable electrode joint. A corrugated portion is provided, and a movable electrode having an electrode layer formed on the surface of a ceramic material is fixed to a movable electrode joint portion via a support member, and an electrode layer is formed on one side of the ceramic material and a heater layer is formed on the other side. The fixed electrode is fixed on a spacer in opposition to the movable electrode, and the height from the upper peripheral portion of the bottom plate to the fixed electrode is reduced, thereby forming an electrostatic capacitance type pressure sensor which is not affected by the environment. .
本発明は上記のように構成したので、ダイヤフラムと
底板の間の室内に導入される流体の圧力によってダイヤ
フラムは変形し、それにともなって可動電極と固定電極
間の距離が変化し、両電極で構成されるコンデンサとし
ての静電容量が変化して流体圧力を電気量に変換する。
流体を導入する開口を備えた底板の上面中央に凹所を設
け、底板の外周上部にスペーサを立設し、底板の外周上
部とスペーサとの間にダイヤフラムの外周縁に形成した
底板接合部を挟持したので、底板と可動電極との高さが
低くなり、底板と固定電極間のスペーサの高さが低くな
る。またセラミックからなる可動電極は軽量となる。Since the present invention is configured as described above, the diaphragm is deformed by the pressure of the fluid introduced into the chamber between the diaphragm and the bottom plate, and accordingly, the distance between the movable electrode and the fixed electrode is changed, so that the two electrodes are used. As a result, the capacitance of the capacitor changes and converts the fluid pressure into an electric quantity.
A recess is provided in the center of the upper surface of the bottom plate provided with an opening for introducing a fluid, a spacer is erected on the outer peripheral upper portion of the bottom plate, and a bottom plate joint formed on the outer peripheral edge of the diaphragm between the outer peripheral upper portion of the bottom plate and the spacer. Because of the sandwiching, the height between the bottom plate and the movable electrode is reduced, and the height of the spacer between the bottom plate and the fixed electrode is reduced. In addition, the movable electrode made of ceramic is light in weight.
本発明の実施例を図面に沿って説明する。第１図にお
いて、検出する流体を導入する開口１を備えた底板２の
上面中央には凹所３を設け、底板２の外周上部には円筒
状のスペーサ４を立設する。スペーサ４は例えば熱膨張
係数の小さいセラミック製または金属製等からなり、底
板２への固定に際し、ダイヤフラム５の外周縁に形成し
た平板状の底板接合部６を挾持することによりダイヤフ
ラム５を固定する。なお、スペーサを金属製とするとき
はリード線18,21とは絶縁が必要である。ダイヤフラム
５はその中央部に平板状の可動電極接合部７を有し、そ
の上面に絶縁材等からなる支持部材８を介してセラミッ
ク素材からなる平板状の可動電極10を固定する。ダイヤ
フラム５の外周の底板接合部６と中央の可動電極接合部
７との間には波板状の波部11を有する。底板接合部６と
波部11との接続部は、波部11の底部12において接続して
おり、波部11と可動電極接合部７との接続部も波部11の
底部12で接続している。セラミック製等からなるスペー
サ４の上部には、リング14によりセラミック素材からな
る固定電極15を挾持して固定する。可動電極10における
固定電極15側の表面にはメタライズしたニッケルメッキ
層を形成して電極層16となし、スペーサ４の通孔17を通
るリード線18を接続する。固定電極15の可動電極10側の
表面にはメタライズしたニッケルメッキ層を形成して電
極層19となし、固定電極15のスペーサ外に突出した端子
部20においてリード線21と接続する。可動電極10の電極
層16と固定電極15の電極層19とは平行に近接して配置さ
れ、この部分でコンデンサ22を構成し、リード線18,21
を発振器に連結する。固定電極15の前記電極層19の反対
側の面にはプリント配線からなるヒータ層23を設け、コ
ンデンサ部に露の付着を防止するための加熱部とする。An embodiment of the present invention will be described with reference to the drawings. In FIG. 1, a concave portion 3 is provided at the center of the upper surface of a bottom plate 2 provided with an opening 1 for introducing a fluid to be detected, and a cylindrical spacer 4 is erected on the upper outer periphery of the bottom plate 2. The spacer 4 is made of, for example, ceramic or metal having a small coefficient of thermal expansion. When the spacer 4 is fixed to the bottom plate 2, the diaphragm 5 is fixed by sandwiching a flat bottom plate joint 6 formed on the outer peripheral edge of the diaphragm 5. . When the spacer is made of metal, it is necessary to insulate it from the lead wires 18 and 21. The diaphragm 5 has a plate-shaped movable electrode joint 7 at the center thereof, and a plate-shaped movable electrode 10 made of a ceramic material is fixed on the upper surface thereof via a support member 8 made of an insulating material or the like. A corrugated plate-shaped wave portion 11 is provided between the bottom plate joint 6 on the outer periphery of the diaphragm 5 and the movable electrode joint 7 at the center. The connecting portion between the bottom plate joint 6 and the corrugated portion 11 is connected at the bottom 12 of the corrugated portion 11, and the connecting portion between the corrugated portion 11 and the movable electrode joint 7 is also connected at the bottom 12 of the corrugated portion 11. I have. A fixed electrode 15 made of a ceramic material is sandwiched and fixed by a ring 14 on the upper part of the spacer 4 made of a ceramic or the like. A metallized nickel plating layer is formed on the surface of the movable electrode 10 on the fixed electrode 15 side to form an electrode layer 16, and a lead wire 18 passing through a through hole 17 of the spacer 4 is connected. A metallized nickel plating layer is formed on the surface of the fixed electrode 15 on the movable electrode 10 side to form an electrode layer 19, and is connected to the lead wire 21 at a terminal portion 20 of the fixed electrode 15 protruding outside the spacer. The electrode layer 16 of the movable electrode 10 and the electrode layer 19 of the fixed electrode 15 are disposed in parallel and close to each other, and a capacitor 22 is formed at this portion, and the lead wires 18 and 21 are formed.
Is connected to the oscillator. A heater layer 23 made of a printed wiring is provided on the surface of the fixed electrode 15 on the side opposite to the electrode layer 19, and serves as a heating section for preventing adhesion of dew to the capacitor section.
上記構成により、室13内に導入された流体の圧力に応
じてダイヤフラム５は図中上下方向に移動し、固定電極
15に対する可動電極10の相対位置が変化するため、各電
極で構成されるコンデンサの電極間位置が変化し、この
コンデンサの静電容量が変化する。その静電容量の変化
を発振器に導いて周波数変化とし、更にそれを電圧変化
に変換する等によって流体圧力の変化を電気的変化に変
換し測定を行う。このような圧力センサにおいて、ダイ
ヤフラム５と可動電極10を支持部材８を介して接合する
部分は、ダイヤフラムの波部11における底部12と接続す
る可動電極接合部７において接合しているので、ダイヤ
フラムの底板接合部６から可動電極10までの高さは第４
図に示した従来のものと比較して明らかのように低くな
る。したがってスペーサ４の底板２上面から固定電極15
までの高さH1も低くなり、熱膨張によってセンサの性能
に最も影響を与えるこの高さH1が小さくなるため、この
圧力センサの熱による特性変化が少なくなる。With the above configuration, the diaphragm 5 moves in the vertical direction in the figure according to the pressure of the fluid introduced into the chamber 13, and the fixed electrode
Since the relative position of the movable electrode 10 with respect to 15 changes, the position between the electrodes of the capacitor formed by each electrode changes, and the capacitance of this capacitor changes. The change in the capacitance is guided to an oscillator to be a frequency change, and the change in the fluid pressure is converted into an electrical change by, for example, converting the change into a voltage change. In such a pressure sensor, the portion that joins the diaphragm 5 and the movable electrode 10 via the support member 8 is joined at the movable electrode joint 7 that connects to the bottom 12 of the wave portion 11 of the diaphragm. The height from the bottom plate joint 6 to the movable electrode 10 is 4th
As is apparent from the comparison with the conventional one shown in FIG. Therefore, the fixed electrode 15 is moved from the upper surface of the bottom plate 2 of the spacer 4.
The height H 1 to be lowered, since the height H 1 which most affect the performance of the sensor due to thermal expansion is reduced, thermal characteristics change due to the pressure sensor is reduced.
第２図に示した第２実施例はその基本構成は第１図に
示したものと同様であり、相違点はダイヤフラム５にお
ける底板接合部６と波部11との接続部を、波部11の中間
部25としたものである。それによりダイヤフラムの可動
電極取付部７と可動電極10上端との高さｈは第１図に示
すものと変わらないにもかかわらず、スペーサ４の底板
上面から固定電極15までの高さH2は第１図に示すものの
高さH1より小さくなる。したがってこの圧力センサの耐
熱特性は更に向上する。The basic structure of the second embodiment shown in FIG. 2 is the same as that shown in FIG. 1 except that the connection between the bottom plate joint 6 and the wave part 11 in the diaphragm 5 is different from the wave part 11 shown in FIG. In the middle part 25 of FIG. Even though it by the height h of the movable electrode mounting portion 7 and the movable electrode 10 the upper end of the diaphragm is not changed from that shown in FIG. 1, the height H 2 of the bottom plate upper surface of the spacer 4 to the fixed electrode 15 smaller than the height H 1 of that shown in Figure 1. Therefore, the heat resistance of the pressure sensor is further improved.
第３図に示す第３実施例においては、ダイヤフラム５
の底板取付部６の波部11との接続部は、波部11の頂部26
において接続している。このように構成することによ
り、スペーサ４の前記高さH3は前記核実施例の高さH1,H
2よりも小さくなり、このセンサの熱に対する特性変化
を小さくすることができる。In the third embodiment shown in FIG.
The connecting portion of the bottom plate attaching portion 6 with the corrugated portion 11 is a top portion 26 of the corrugated portion 11.
Are connected. With this configuration, the height H 3 of the spacer 4 height H 1, H of the core examples
2, the characteristic change of the sensor with respect to heat can be reduced.
なお、上記実施例において、スペーサとしてセラミッ
クを用いた例を示したが、合成樹脂製のものを用いても
良く、同様に耐熱特性が向上するばすりでなく、合成樹
脂が吸水性を有して膨潤する性質がある場合にも、スペ
ーサの前記高さＨが小さくなるので膨潤量が小さくな
る。In the above embodiment, an example in which ceramic is used as the spacer is shown, but a spacer made of a synthetic resin may be used. Similarly, not only the heat resistance is improved, but also the synthetic resin has a water absorbing property. Also, when the spacer has the property of swelling, the height H of the spacer is reduced, so that the swelling amount is reduced.
本発明は上記のように構成し作用するので、ダイヤフ
ラムの底板接合部から可動電極までの高さが小さくな
り、熱膨脹によるセンサの性能に与える影響が少なくな
り、センサの性能が向上する。またセンサを、膨脹性を
有する合成樹脂で製造した場合においては、膨潤量が減
少するのでセンサの耐水特性も向上する。Since the present invention is constructed and operates as described above, the height from the bottom plate joint of the diaphragm to the movable electrode is reduced, and the influence of the thermal expansion on the performance of the sensor is reduced, and the performance of the sensor is improved. When the sensor is made of a swellable synthetic resin, the amount of swelling is reduced, so that the water resistance of the sensor is also improved.
第１図は本発明の第１実施例の断面図、第２図は同第２
実施例の断面図、第３図は同第３実施例の断面図、第４
図は従来例の断面図である。 2:底板、3:凹所 4:スペーサ、5:ダイヤフラム 6:底板接合部、7:可動電極接合部 11:波部、13:室 15:固定電極、16,17:電極層 22:コンデンサ、23:ヒータ層FIG. 1 is a sectional view of a first embodiment of the present invention, and FIG.
FIG. 3 is a sectional view of the third embodiment, and FIG.
The figure is a sectional view of a conventional example. 2: Bottom plate, 3: Concavity 4: Spacer, 5: Diaphragm 6: Bottom plate joint, 7: Movable electrode joint 11: Corrugated, 13: Chamber 15: Fixed electrode, 16, 17: Electrode layer 22: Capacitor, 23: heater layer
───────────────────────────────────────────────────── フロントページの続き (72)発明者 高柳 良一郎 埼玉県所沢市青葉台1311 株式会社鷺宮 製作所所沢事業所内 (72)発明者 竹内 明彦 埼玉県所沢市青葉台1311 株式会社鷺宮 製作所所沢事業所内 (56)参考文献 実開 平２−95832（ＪＰ，Ｕ) 実開 平１−102841（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.6，ＤＢ名) G01L 9/12 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ryoichiro Takayanagi 1311 Aobadai, Tokorozawa-shi, Saitama Pref. References Hira 2-95832 (JP, U) Hira 1-102841 (JP, U) (58) Fields studied (Int. Cl. 6 , DB name) G01L 9/12
Claims (4)
央に凹所を設け、底板の外周上部にスペーサを立設し、
底板の外周上部とスペーサとの間にダイヤフラムの外周
縁に形成した底板接合部を挟持し、ダイヤフラムの底板
接合部と中央の可動電極接合部との間に波部を備え、可
動電極接合部には支持部材を介してセラミック素材の表
面に電極層を形成した可動電極を固定し、セラミック素
材の片側に電極層を形成し他側にヒータ層を形成した固
定電極を前記可動電極に対向してスペーサ上に固定し、
前記底板の外周上部から固定電極までの高さを小さくし
たことを特徴とする静電容量式圧力センサ。A bottom is provided at the center of the upper surface of a bottom plate having an opening for introducing a fluid, and a spacer is erected on an upper portion of the outer periphery of the bottom plate;
A bottom plate joint formed on the outer peripheral edge of the diaphragm is sandwiched between the outer periphery upper portion of the bottom plate and the spacer, and a wave portion is provided between the bottom plate joint of the diaphragm and the central movable electrode joint, and the movable electrode joint is provided. A movable electrode having an electrode layer formed on the surface of a ceramic material is fixed via a support member, and a fixed electrode having an electrode layer formed on one side of the ceramic material and a heater layer formed on the other side is opposed to the movable electrode. Fixed on the spacer,
A capacitance type pressure sensor, wherein a height from an upper peripheral portion of the bottom plate to a fixed electrode is reduced.
で接続し、波部と可動電極接合部との接合部は波部の底
部で接続してなる特許請求の範囲第１項記載の静電容量
式圧力センサ。2. A joint between a bottom plate joint and a corrugated portion is connected at the bottom of the corrugated portion, and a joint between the corrugated portion and the movable electrode joint is connected at the bottom of the corrugated portion. 2. A capacitance type pressure sensor according to claim 1.
部で接続し、波部と可動電極接合部との接合部は波部の
底部で接続してなる特許請求の範囲第１項記載の静電容
量式圧力センサ。3. A joint between the bottom plate joint and the corrugated portion is connected at an intermediate portion of the corrugated portion, and a joint between the corrugated portion and the movable electrode joint is connected at the bottom of the corrugated portion. 2. The capacitance type pressure sensor according to claim 1.
で接続し、波部と可動電極接合部との接合部は波部の底
部で接続してなる特許請求の範囲第１項記載の静電容量
式圧力センサ。4. The joint between the bottom plate joint and the corrugated portion is connected at the top of the corrugated portion, and the joint between the corrugated portion and the movable electrode joint is connected at the bottom of the corrugated portion. 2. A capacitance type pressure sensor according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30271790A JP2912949B2 (en) | 1990-11-09 | 1990-11-09 | Capacitive pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30271790A JP2912949B2 (en) | 1990-11-09 | 1990-11-09 | Capacitive pressure sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04177137A JPH04177137A (en) | 1992-06-24 |
| JP2912949B2 true JP2912949B2 (en) | 1999-06-28 |
Family
ID=17912328
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30271790A Expired - Fee Related JP2912949B2 (en) | 1990-11-09 | 1990-11-09 | Capacitive pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2912949B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5902933A (en) * | 1993-02-22 | 1999-05-11 | Omron Corporation | Pressure sensor and its application |
| JP2900235B2 (en) * | 1995-07-17 | 1999-06-02 | 株式会社山武 | Capacitive pressure sensor |
| CN107957312A (en) * | 2017-12-13 | 2018-04-24 | 沈阳市传感技术研究所 | The capacitive pressure transducer of corrugated moving electrode |
-
1990
- 1990-11-09 JP JP30271790A patent/JP2912949B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04177137A (en) | 1992-06-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3416140B2 (en) | Capacitive pressure sensor | |
| JP2854896B2 (en) | pressure sensor | |
| US4426673A (en) | Capacitive pressure transducer and method of making same | |
| US5150275A (en) | Capacitive pressure sensor | |
| KR0137939B1 (en) | Capacitive pressure sensor and method for minimizing the parasitic capacitance in a capacitive pressure sensor | |
| US4388668A (en) | Capacitive pressure transducer | |
| JP2003506706A (en) | Capacitive pressure sensor with encapsulated resonant member | |
| KR0137965B1 (en) | Capacitive sensor with minimized dielectric drift | |
| US5635649A (en) | Multi-function differential pressure sensor with thin supporting base | |
| US4207604A (en) | Capacitive pressure transducer with cut out conductive plate | |
| US6789429B2 (en) | Capacitive pressure sensor having encapsulated resonating components | |
| KR100441305B1 (en) | flow rate sensor, temperature sensor and flow rate measuring instrument | |
| CA1154545A (en) | Semiconductor variable capacitance pressure transducer assembly | |
| JPS58211617A (en) | Pressure transducer | |
| JPH06500630A (en) | capacitive force sensor | |
| CN1056747A (en) | Load cell | |
| US6718827B1 (en) | Center-mount capacitive sensor with overload protection | |
| US5925824A (en) | Capacitive differential pressure detector | |
| CA1036832A (en) | Pressure sensitive capacitance sensing element | |
| JP2912949B2 (en) | Capacitive pressure sensor | |
| JPS59196401A (en) | Strain gage and manufacture thereof | |
| JPH0743625Y2 (en) | Capacitive load sensor | |
| EP0024945B1 (en) | Variable capacitance pressure transducer | |
| US4354219A (en) | Capacitance sensing device | |
| JPH01501962A (en) | pressure sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |