JPS5930444Y2 - differential pressure detector - Google Patents
differential pressure detectorInfo
- Publication number
- JPS5930444Y2 JPS5930444Y2 JP6249380U JP6249380U JPS5930444Y2 JP S5930444 Y2 JPS5930444 Y2 JP S5930444Y2 JP 6249380 U JP6249380 U JP 6249380U JP 6249380 U JP6249380 U JP 6249380U JP S5930444 Y2 JPS5930444 Y2 JP S5930444Y2
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- diaphragm
- receiving
- semiconductor
- receiving side
- 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
Landscapes
- Measuring Fluid Pressure (AREA)
Description
【考案の詳細な説明】
本考案は、プロセス変量である2点間の圧力差を連続し
て測定する差圧検出器に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a differential pressure detector that continuously measures the pressure difference between two points, which is a process variable.
例えば、管内流体の流量を測定しようとする場合、管内
にオリフィス板を設置して流体抵抗とし、この抵抗の上
下流における圧力差を測定して、所定の演算式に基づき
流量を導き出すことが行なわれる。For example, when trying to measure the flow rate of fluid in a pipe, an orifice plate is installed in the pipe to act as a fluid resistance, the pressure difference upstream and downstream of this resistance is measured, and the flow rate is derived based on a predetermined calculation formula. It will be done.
そのため、従来のこの種の差圧検出器は一般に2枚の受
圧ダイヤフラムに各測定圧力を与えボディ本体内におげ
ろ内封液の移動を封入回路を仕切って設けた半導体ダイ
ヤフラムの歪により電気的な出力として取り出すように
構成されている。For this reason, conventional differential pressure detectors generally apply each measurement pressure to two pressure-receiving diaphragms, and prevent the movement of the internal liquid within the body by electrically controlling the strain of the semiconductor diaphragm that partitions the sealed circuit. It is configured so that it can be output as an output.
かかる構成においてはプロセスの測定仕様に応じて2枚
の受圧ダイヤフラムの寸法、強度、材質などを適宜選択
することができるが、これに十分な神経を拡っても不用
意に過度の負荷を受け、受圧ダイヤフラムが変形すると
とがある。In such a configuration, the dimensions, strength, material, etc. of the two pressure-receiving diaphragms can be selected appropriately according to the measurement specifications of the process, but even if sufficient consideration is given to this, excessive loads may be inadvertently applied. , the pressure-receiving diaphragm may deform.
受圧ダイヤフラムが変形すると精度の高い測定が困難で
、この変形を防ぐ手段としては、ボディ本体の各受圧側
面と受圧ダイヤフラムの間の隙間を小さく設定すると共
に前記受圧側面を受圧ダイヤフラムと同形の波形に形成
して過剰圧力を受けた受圧ダイヤフラムが受圧側面に圧
接されても変形せずにバックアップできるようにしたも
のが知られている。If the pressure-receiving diaphragm is deformed, it is difficult to make highly accurate measurements.To prevent this deformation, the gap between each pressure-receiving side of the body and the pressure-receiving diaphragm is set small, and the pressure-receiving side is made to have the same waveform as the pressure-receiving diaphragm. It is known that a pressure receiving diaphragm that has been formed and subjected to excessive pressure can be backed up without being deformed even if it is pressed against a pressure receiving side surface.
しかし、このような構成を採用したとしても、測定スパ
ン内では受圧ダイヤプラムが受圧側面に接触すると誤差
の原因となり、依然として高精度の測定が困難であった
。However, even if such a configuration is adopted, if the pressure-receiving diaphragm contacts the pressure-receiving side surface within the measurement span, it causes an error, and highly accurate measurement is still difficult.
それ故、受圧側面と受圧ダイヤプラムとの隙間はある程
度太き目に設定する必要があるが、反面過剰圧力を受け
た場合、センサーの半導体ダイヤフラムが破損するとい
った不都合があった。Therefore, it is necessary to set the gap between the pressure-receiving side surface and the pressure-receiving diaphragm to be somewhat thick, but on the other hand, there is a problem that the semiconductor diaphragm of the sensor may be damaged if excessive pressure is applied.
本考案はこのような従来の欠点に鑑みてなされたもので
、受圧ダイヤフラムを円板状ダイヤフラムと環状ダイヤ
フラムで形成してそのいずれか一方をボディ本体の受圧
側面に半導体ダイヤフラムに塑性変形を与える力以下の
力で圧接すると共に各圧力側の封入回路に対抗圧力側の
受圧側面にそれぞれ開口するバイパスを設けるという極
めて簡単な構成により、受圧ダイヤフラムに加わる過剰
圧力を吸収し、半導体ダイヤフラムの破損を防止すると
共に測定精度の向上を計るようにした差圧検出器を提供
するものである。The present invention has been developed in view of these conventional drawbacks.The pressure receiving diaphragm is formed of a disc-shaped diaphragm and an annular diaphragm, and one of them is applied to the pressure-receiving side of the body main body to apply a force that applies plastic deformation to the semiconductor diaphragm. With an extremely simple configuration in which pressure is applied with the following force and a bypass is provided that opens on the pressure-receiving side of the opposing pressure side for each sealed circuit on the pressure side, excess pressure applied to the pressure-receiving diaphragm is absorbed and damage to the semiconductor diaphragm is prevented. In addition, the present invention provides a differential pressure detector which is designed to improve measurement accuracy.
以下、本考案を図面に示す実施例に基づいて詳細に説明
する。Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
第1図は本考案に係る差圧検出器の一実施例を示す縦断
面図、第2図は第1図に示した受圧ダイヤノラムの分解
斜視図、第3図は第1図に示したセンサーの断面図であ
る。Fig. 1 is a longitudinal sectional view showing an embodiment of the differential pressure detector according to the present invention, Fig. 2 is an exploded perspective view of the pressure receiving dianoram shown in Fig. 1, and Fig. 3 is the sensor shown in Fig. 1. FIG.
これらの図において、符号1で示すものは内封液2を封
入してなるボディ本体で、このボディ本体の左右両側面
、すなわチ各受出仰面1atlbには受圧ダイヤフラム
3゜4がその周縁部をそれぞれ固定され噸己設されると
共にこれらの受圧ダイヤフラム3,4を被うようにカバ
ー5,6がボディ本体1に固定されている。In these figures, the reference numeral 1 denotes a body which is sealed with an internal liquid 2, and a pressure receiving diaphragm 3°4 is located on both left and right sides of the body, that is, on each receiving/extending surface 1atlb, at its periphery. Covers 5 and 6 are fixed to the main body 1 so as to cover the pressure receiving diaphragms 3 and 4, respectively.
前記受圧ダイヤフラム3,4は全く同一に形成されるも
ので、それぞれ波形に形成された円板状ダイヤフラムA
と、この円板状ダイヤフラムAの外周を穐り囲む環状ダ
イヤノラムBとで一体的に形成され、かつ環状ダイヤフ
ラムBはそれ自体のバネ習性により、受圧側面1a、1
bにそれぞれ圧接している。The pressure-receiving diaphragms 3 and 4 are formed identically, and each has a disk-shaped diaphragm A formed in a corrugated shape.
and an annular diaphragm B that surrounds the outer periphery of the disc-shaped diaphragm A, and the annular diaphragm B has its own spring behavior, so that the pressure-receiving sides 1a, 1
b are in pressure contact with each other.
この場合、環状ダイヤフラムBの圧接力は安全率を見込
んで後述する半導体ダイヤノラムに塑性変形を与える力
以下に設定され、また各受圧側面1a、lbは前記受圧
ダイヤフラム3゜4と同形の波形に形成されている。In this case, the pressure contact force of the annular diaphragm B is set to be less than the force that causes plastic deformation to the semiconductor diaphragm, which will be described later, in consideration of the safety factor, and each pressure receiving side surface 1a, lb is formed in the same waveform as the pressure receiving diaphragm 3.4. has been done.
円板状ダイヤフラムAと各受圧側面1a、lbとの間に
は適宜な隙間が設けられている。Appropriate gaps are provided between the disc-shaped diaphragm A and each pressure-receiving side surface 1a, lb.
図において左側の受圧ダイヤフラム3の外表面にはカバ
ー5の孔1よりオリフィス上流側の圧力軸が導かれ、右
側の受圧ダイヤフラム3の外表面にはカバー6の孔8よ
りオリフィス下流側の圧力PLが導かれている。In the figure, the pressure axis PL on the upstream side of the orifice from the hole 1 of the cover 5 is guided to the outer surface of the pressure receiving diaphragm 3 on the left side, and the pressure axis PL on the downstream side of the orifice from the hole 8 of the cover 6 is guided on the outer surface of the pressure receiving diaphragm 3 on the right side. is being guided.
前記ボディ本体1内には2つの封入回路9,10が形成
されており、これらの封入回路9,100上端はボディ
本体1の上部に設けられ、ハーメチックシール11によ
って密閉されている上部室12にそれぞれ連通され、下
端は前記各受圧側面1a。Two sealed circuits 9 and 10 are formed in the body 1, and the upper ends of these sealed circuits 9 and 10 are connected to an upper chamber 12 that is provided in the upper part of the body 1 and sealed by a hermetic seal 11. The lower end is connected to each pressure receiving side surface 1a.
1bの円板状ダイヤノラムAと対向する部分に開口され
ている。It is opened at a portion of 1b facing the disc-shaped diamondorum A.
lた、前記封入回路9,10にはそれぞれ対向圧力側の
受圧側面1b、1bの環状ダイヤフラムBと対向する部
分に開口するバイパス13,14がそれぞれ設けられで
いる。In addition, the sealed circuits 9 and 10 are provided with bypasses 13 and 14, respectively, which open at portions of the pressure-receiving sides 1b and 1b facing the annular diaphragm B on the opposite pressure side.
前記上部室12には前記内側液2が封入されると共にセ
ンサー15が配設されている。The inner liquid 2 is sealed in the upper chamber 12 and a sensor 15 is disposed therein.
このセンサー15は第3図に示すように上部室12の底
面12a上に載置固定されるシリコンベース16と、シ
リコンベース16上に固定されて上面が円形の半導体ダ
イヤフラム17を構成するカップ状のシリコンウェハ1
8と、半導体ダイヤフラムIIの起歪部に拡散法などに
より設けられてブリッジ結線されたストレンゲージ19
と力ら構成さへ前副半導体ダイヤフラム17の上側に封
入回路9を介して圧力PHが与えられ、下端に封入回路
10およびシリコンベース16の貫通孔20を介して圧
力PLが与えられている。As shown in FIG. 3, this sensor 15 consists of a silicon base 16 placed and fixed on the bottom surface 12a of the upper chamber 12, and a cup-shaped semiconductor diaphragm 17 fixed on the silicon base 16 and having a circular top surface. silicon wafer 1
8, and a strain gauge 19 provided by a diffusion method or the like on the strain-generating portion of the semiconductor diaphragm II and connected with a bridge.
Pressure PH is applied to the upper side of the front sub-semiconductor diaphragm 17 via the encapsulation circuit 9, and pressure PL is applied to the lower end via the encapsulation circuit 10 and the through hole 20 of the silicon base 16.
かかる構成において、通常の圧力測定時においては内側
液2を介して受圧ダイヤフラム3,4には差圧P H−
p Lに応じた力が図において右向きに与えられ、この
力が封入回路9,10を通って上部室12内のセンサー
15に導かれる。In this configuration, during normal pressure measurement, a differential pressure P H- is applied to the pressure receiving diaphragms 3 and 4 via the inner liquid 2.
A force corresponding to p L is applied to the right in the figure, and this force is guided to the sensor 15 in the upper chamber 12 through the enclosed circuits 9 and 10.
このため、半導体ダイヤフラム17は差圧PH−pLに
応シて2点鎖線で示すように変形し、この変形がストレ
ンゲージ19によって電気的に取り出され、第1図に示
す増隅器21で増幅された後計器に表示ないし遠隔発信
される。Therefore, the semiconductor diaphragm 17 deforms as shown by the two-dot chain line in response to the differential pressure PH-pL, and this deformation is electrically extracted by the strain gauge 19 and amplified by the angle intensifier 21 shown in FIG. After that, it is displayed on the instrument or transmitted remotely.
次に、例えばオリフィス上流側に過剰圧力か生じると、
受圧ダイヤノラム3の円板状ダイヤフラムA力佑方に押
圧されて撓むため、この過剰圧力が封入回路9内の内封
液2を介して半導体ダイヤフラム11に伝達されると共
にバイパス13を通って受圧ダイヤフツム4の環状ダイ
ヤフラムBに伝達される。Next, for example, if excessive pressure occurs upstream of the orifice,
Since the disk-shaped diaphragm A of the pressure-receiving diaphragm 3 is pressed in the opposite direction and deflects, this excess pressure is transmitted to the semiconductor diaphragm 11 via the sealed liquid 2 in the sealed circuit 9 and passes through the bypass 13 to receive the pressure. It is transmitted to the annular diaphragm B of the diaphragm 4.
この場合、環状ダイヤフラムBは上述した通り半導体ダ
イヤフラム1Tに塑性変形を与えるより小さいばね習性
を有しているので、過剰圧力によってこの環状ダイヤフ
ラムBが右方に押されてバイパス13を開く。In this case, since the annular diaphragm B has a smaller spring behavior than the plastic deformation of the semiconductor diaphragm 1T as described above, the annular diaphragm B is pushed to the right by the excess pressure to open the bypass 13.
したがって、封入回路9内の内封液2がバイパス13を
通って受圧側面1bと受圧ダイヤノラム4との間に流れ
込んで、過剰圧力をオリフィス下流側に逃がし、この過
剰圧力が受圧ダイヤフラム4を介してPL側に吸収され
る。Therefore, the sealed liquid 2 in the sealed circuit 9 flows between the pressure receiving side surface 1b and the pressure receiving diaphragm 4 through the bypass 13, and the excess pressure is released to the downstream side of the orifice. Absorbed by the PL side.
そして、このようにしてPH側の過剰圧力がpL側に吸
収された後は、受圧ダイヤフラム4の環状ダイヤフラム
Bのばね習性によって受圧11fiI 1 bと受圧ダ
イヤフラム4の間の隙間に過剰に移動した内封液2をバ
イパス13を介して封入回路9側に戻し、測定スパン内
での正常な圧力側床を可能にする。After the excess pressure on the PH side is absorbed into the pL side in this way, the internal pressure that has moved excessively into the gap between the pressure receiving 11fiI 1 b and the pressure receiving diaphragm 4 due to the spring behavior of the annular diaphragm B of the pressure receiving diaphragm 4 is The sealing liquid 2 is returned to the enclosure circuit 9 side via the bypass 13, allowing a normal pressure side bed within the measurement span.
一方、オリフィス下流側に過剰圧力が生じた場合にに%
受圧ダイヤフラム4Aの左方への移動に伴(1封入回路
10内の内封液2がバイパス14じ導かれて、受圧ダイ
ヤフラム3の環状ダイヤノラムBを押圧するため、この
場合においても上記したと同様前記環状ダイヤフラムB
の変形により下流側に生じた過剰圧力がオリフィス上流
側に吸収される。On the other hand, if excessive pressure occurs downstream of the orifice,
As the pressure receiving diaphragm 4A moves to the left (the sealed liquid 2 in the sealed circuit 10 is guided through the bypass 14 and presses the annular diaphragm B of the pressure receiving diaphragm 3, the same process as described above occurs in this case as well) Said annular diaphragm B
The excess pressure generated on the downstream side due to the deformation of is absorbed on the upstream side of the orifice.
かくして、このような構成によれば過剰圧力を各圧力側
の封入回路に設けたバイパス13.14を介して対抗圧
力側に逃すことができるので、半導体ダイヤフラム17
が破損したりする虞れがなく、良好かつ精度の高い差圧
測定を行なうことができる。Thus, with such an arrangement, excess pressure can be released to the opposing pressure side via the bypass 13,14 provided in the enclosed circuit on each pressure side, so that the semiconductor diaphragm 17
It is possible to perform good and highly accurate differential pressure measurements without the risk of damage.
また、構成が単純で、環状ダイヤフラムBによって比較
約コンパクトにできる。In addition, the structure is simple, and the annular diaphragm B makes it relatively compact.
第4図は本考案の他の実施例を示す要部断面図である。FIG. 4 is a sectional view of a main part showing another embodiment of the present invention.
この実施例においv工、各受圧ダイヤフラム3,4の円
板状ダイヤフラムAに、半導体ダイヤフラムに塑性変形
を与える力以下のばね習性を与えて各受圧側面1a、I
bに圧接させ、環状ダイヤフラムBと各受圧側面1a、
1bとの間ニ適宜な隙間を設けた点が上記実施例と異な
っている。In this embodiment, the disk-shaped diaphragm A of each pressure-receiving diaphragm 3, 4 is given a spring behavior less than the force that causes plastic deformation to the semiconductor diaphragm, and each pressure-receiving side surface 1a, I
b, the annular diaphragm B and each pressure-receiving side surface 1a,
It differs from the above embodiment in that an appropriate gap is provided between it and 1b.
このような構成においても、過剰圧力が生じると、受圧
ダイヤフラム3または4が右渣たは左に押圧されて撓み
、過剰圧力を対抗圧力側に逃すので、上記実施例と同様
、半導体ダイヤフラムを保護することができることは明
らかであろう。Even in such a configuration, when excessive pressure occurs, the pressure receiving diaphragm 3 or 4 is pressed to the right or left and flexes, releasing the excess pressure to the opposing pressure side, so that the semiconductor diaphragm is protected as in the above embodiment. It should be obvious that you can.
以上説明したように、本考案に係る差圧検出器によれば
、受圧ダイヤフラムを円板状ダイヤフラムと環状ダイヤ
フラムとで形成して、そのいずれか一方に半導体ダイヤ
フラムに塑性変形を与える力以下のばね性を与えて受圧
側面に圧接させると共に各圧力側の封入回路に対抗圧M
llOll個面にそれぞれ開口するバイパスを設けて受
圧ダイヤフラムに加えられる過剰圧力を対抗圧力側1に
逃すように構成したので、半導体ダイヤフラムの破損を
防止することができ、精度の高い測定を可能にすると共
−灸出器自体の耐久性を向上させることができ、その効
果は非常に大である。As explained above, according to the differential pressure detector according to the present invention, the pressure receiving diaphragm is formed of a disk-shaped diaphragm and an annular diaphragm, and either one of the pressure-receiving diaphragms is provided with a spring having a force that is less than or equal to the force that applies plastic deformation to the semiconductor diaphragm. In addition to applying pressure to the pressure-receiving side, counter pressure M is applied to the enclosed circuit on each pressure side.
By-passes opening on each surface of llOll are provided so that excess pressure applied to the pressure-receiving diaphragm is released to the opposing pressure side 1, which prevents damage to the semiconductor diaphragm and enables highly accurate measurement. The durability of the co-moxibustion device itself can be improved, and the effect is very large.
第1図は本考案に係る差圧検出器の一実施例を示す縦断
面図、第2図は第1図に示した受圧ダイヤフラムの分解
斜視図、第3図は第1図に示したセンサーの断面図、第
4図は本考案の他の実施例を示す要部断面図である。
1・・・・・・ボディ本体、2・・・・・・内封液、3
,4・・・・・・受圧ダイヤフラム 9,10・・・・
・・封入回路、13゜14・・・・・・バイパス、15
・・・・・・センサー、17・・・・・・半導体ダイヤ
フラム、A・・・・・・円板状ダイヤフラム、B・・・
・・・環状ダイヤフラム。Fig. 1 is a vertical sectional view showing an embodiment of the differential pressure detector according to the present invention, Fig. 2 is an exploded perspective view of the pressure receiving diaphragm shown in Fig. 1, and Fig. 3 is the sensor shown in Fig. 1. FIG. 4 is a sectional view of a main part showing another embodiment of the present invention. 1...Body main body, 2...Inner sealing liquid, 3
, 4... Pressure receiving diaphragm 9, 10...
... Enclosed circuit, 13゜14 ... Bypass, 15
...Sensor, 17...Semiconductor diaphragm, A...Disc-shaped diaphragm, B...
...Annular diaphragm.
Claims (1)
体内におげろ内封液の移動を封入回路を仕切って設けた
半導体ダイヤフラムの歪により電気的な出力として取り
出すようにした差圧検出器において、前記受圧ダイヤフ
ラムをそれぞれ波形に形成された円板状ダイヤフラムと
、この円筒状ダイヤフラムの外周を取り囲む環状ダイヤ
フラムで形成し、ボディ本体の各受圧側面を前記受圧ダ
イヤフラムと同形の波形に形成し、前記円板状ダイヤフ
ラムと環状ダイヤノラムのいずれか一方は前記受圧側面
に前記半導体ダイヤフラムに塑性変形を与える力以下の
力で圧接し、かつ前記各圧力側の封入回路に対抗圧力側
の受圧側面にそれぞれ1iするバイパスを設けたことを
特徴とする差圧検出器。In a differential pressure detector, each measurement pressure is applied to two pressure-receiving dianorams, and the movement of the liquid sealed inside the body is extracted as an electrical output by straining a semiconductor diaphragm that partitions the sealed circuit. , the pressure receiving diaphragm is formed of a disc-shaped diaphragm formed in a corrugated shape and an annular diaphragm surrounding the outer periphery of the cylindrical diaphragm, each pressure receiving side surface of the body main body is formed in the same waveform as the pressure receiving diaphragm, Either one of the disk-shaped diaphragm and the annular diaphragm is pressed against the pressure-receiving side surface with a force that is less than the force that causes plastic deformation of the semiconductor diaphragm, and the pressure-receiving side surface on the pressure side opposite to the sealed circuit on each pressure side is in contact with the pressure-receiving side surface. A differential pressure detector characterized by being provided with a bypass.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6249380U JPS5930444Y2 (en) | 1980-05-09 | 1980-05-09 | differential pressure detector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6249380U JPS5930444Y2 (en) | 1980-05-09 | 1980-05-09 | differential pressure detector |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS56164143U JPS56164143U (en) | 1981-12-05 |
JPS5930444Y2 true JPS5930444Y2 (en) | 1984-08-30 |
Family
ID=29656798
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6249380U Expired JPS5930444Y2 (en) | 1980-05-09 | 1980-05-09 | differential pressure detector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5930444Y2 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1172640A1 (en) * | 2000-07-13 | 2002-01-16 | Endress + Hauser GmbH + Co. | Differential pressure sensor |
NO326583B1 (en) * | 2007-06-08 | 2009-01-12 | Presens As | Differential pressure Templates |
-
1980
- 1980-05-09 JP JP6249380U patent/JPS5930444Y2/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
JPS56164143U (en) | 1981-12-05 |
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