JPS5832334B2 - Flow velocity flow measuring device - Google Patents
Flow velocity flow measuring deviceInfo
- Publication number
- JPS5832334B2 JPS5832334B2 JP53069632A JP6963278A JPS5832334B2 JP S5832334 B2 JPS5832334 B2 JP S5832334B2 JP 53069632 A JP53069632 A JP 53069632A JP 6963278 A JP6963278 A JP 6963278A JP S5832334 B2 JPS5832334 B2 JP S5832334B2
- Authority
- JP
- Japan
- Prior art keywords
- container
- vortex generator
- tube
- measuring device
- vortex
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
- G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
- G01F1/32—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow using swirl flowmeters
- G01F1/325—Means for detecting quantities used as proxy variables for swirl
- G01F1/3259—Means for detecting quantities used as proxy variables for swirl for detecting fluid pressure oscillations
- G01F1/3266—Means for detecting quantities used as proxy variables for swirl for detecting fluid pressure oscillations by sensing mechanical vibrations
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
Description
【発明の詳細な説明】
本発明はカルマン渦を利用した流速流量測定装置に関す
るものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flow rate measuring device using Karman vortices.
更に詳述すれば、カルマン渦により渦発生体に生ずる交
番力を検出して、渦信号として取り出し流速流量を測定
する流速流量測定装置に関するものである。More specifically, the present invention relates to a flow rate measuring device that detects the alternating force generated in a vortex generating body by a Karman vortex and extracts it as a vortex signal to measure the flow rate.
従来より一般に使用されているカルマン渦を利用した流
速流量測定装置にむいては、管路に渦発生体を抜き差し
自在に固定するのが一般的である。In conventional flow velocity measuring devices that utilize Karman vortices, which have been commonly used, it is common to fix a vortex generator to a pipe so that it can be inserted into and removed from the pipe.
而して、検出器を渦発生体、あるいは渦発生体の下流に
配置して渦発生体により発生した渦発生周波数を検出す
る。Thus, a detector is placed at the vortex generator or downstream of the vortex generator to detect the vortex generation frequency generated by the vortex generator.
このようなものにおいては、管路に渦発生体を固定、支
持するための固定、支持機構が必要であり、抜き差し出
来るようにするための、たとえば、シール機構等の構成
が複雑になり、価格も高くｉる。In such a device, a fixing and supporting mechanism is required to fix and support the vortex generator in the pipe, and the structure of the sealing mechanism, etc. to enable insertion and removal becomes complicated and expensive. It's also expensive.
また頑丈さに欠け、小型化するにも釦のすと制約がある
。It also lacks sturdiness, and there are limitations to the size of the button.
また、被測定流体に接する部分に釦いて、管路と渦発生
体との間に隙間や窪みが生ずるので、腐食性流体に対す
る耐食性がよくない。Further, since a gap or depression is formed between the pipe line and the vortex generator at the part that comes into contact with the fluid to be measured, corrosion resistance against corrosive fluids is poor.
本発明はこれらの問題点を解決したものである。The present invention solves these problems.
本発明の目的はシンプルな構成により頑丈、安価で、小
型化、軽量化がはかれ、耐食性のよい流速流量測定装置
を提供するにある。An object of the present invention is to provide a flow rate measuring device having a simple structure, being sturdy, inexpensive, compact, lightweight, and having good corrosion resistance.
第１図Ａ、Ｂ、Ｃは本発明の一実施例の構成説明図で、
Ａは縦断面図、Ｂは側断面図、Ｃは要部構成説明図であ
る。FIGS. 1A, B, and C are configuration explanatory diagrams of an embodiment of the present invention,
A is a longitudinal cross-sectional view, B is a side cross-sectional view, and C is an explanatory diagram of the main part configuration.
図に訃いて、１は円筒状の管体、２は管体１に直角に挿
入された、この場合は台形柱状の渦発生体である。In the figure, 1 is a cylindrical tube, and 2 is a trapezoidal columnar vortex generator inserted at right angles to the tube 1.
３は力検出部で、検出センサ部３１、封着体３２と底を
有する円筒状の容器３３よりなり、一端は渦発生体２に
接続された他端は管体１に固定されている。Reference numeral 3 denotes a force detection section, which is composed of a detection sensor section 31, a sealing body 32, and a cylindrical container 33 having a bottom, one end of which is connected to the vortex generator 2 and the other end fixed to the tube body 1.
而して、管体１、渦発生体２と容器３３は一体的に構成
されている。Thus, the tube body 1, the vortex generator 2, and the container 33 are integrally constructed.
検出、センサ部３１はこの場合はＣ図に示す如く、円板
状の素子本体３１１と電極３１２，３１３，３１４より
なる。In this case, the detection and sensor section 31 consists of a disk-shaped element body 311 and electrodes 312, 313, and 314, as shown in Figure C.
電極３１２は薄円板状をなし、素子本体３１１の一面側
に設けられている。The electrode 312 has a thin disk shape and is provided on one side of the element body 311.
一方、電極３１３．３１４はほぼ弓形をなし、素子本体
３１１の他面側に素子本体３１１の中心を挾んで、対称
形に設けられ、渦発生体２の軸心をはさんで流路方向と
直角方向に対称になるように配置されている。On the other hand, the electrodes 313 and 314 have a substantially arcuate shape, and are provided symmetrically on the other side of the element body 311, sandwiching the center of the element body 311, and facing the flow path direction across the axis of the vortex generator 2. They are arranged symmetrically in the right angle direction.
素子本体３１１はこの場合はニオブ酸リチウム（ＬｉＮ
ｂ０３）よりなる圧電素子が使用されている。In this case, the element body 311 is made of lithium niobate (LiN
A piezoelectric element made of b03) is used.
封着体３２は絶縁材よりなり、検出センサ部３１を容器
３３内に容器３３より絶縁して封着する封着体で、この
場合はガラス材が用いられている。The sealing body 32 is made of an insulating material, and is a sealing body that seals the detection sensor section 31 inside the container 33 while being insulated from the container 33. In this case, a glass material is used.
以上の構成において、管体１内に被測定流体が流れると
渦発生体２にはカルマン渦により第１図Ｂに示す矢印Ｘ
のよう々交番力が作用する。In the above configuration, when the fluid to be measured flows in the tube body 1, the vortex generating body 2 is caused by the Karman vortex, which is indicated by the arrow X shown in FIG. 1B.
An alternating force acts like this.
この交番力は容器３３、封着体３２を介して検出センサ
部３１に伝達される。This alternating force is transmitted to the detection sensor section 31 via the container 33 and the sealed body 32.
この場合、渦発生体２には第１図Ｂに示す如く、渦発生
体２の中心軸をはさんで逆方向の応力変化が発生する。In this case, stress changes occur in the vortex generator 2 in opposite directions across the central axis of the vortex generator 2, as shown in FIG. 1B.
而して、検出センサ部３１の電極３１２−電極３１３、
電極３１２−電極３１４間にはこの応力変化に対応した
電気信号（たとえば電圧の変化）が生ずる。Thus, the electrode 312-electrode 313 of the detection sensor section 31,
An electrical signal (for example, a voltage change) corresponding to this stress change is generated between the electrode 312 and the electrode 314.
この変化の回数を検出することにより渦発生周波数が検
出できる。By detecting the number of times this change occurs, the vortex generation frequency can be detected.
而して、電極３１２−電極３１３、電極３１２−電極３
１４間の電気出力を差動的に処理すれば、２倍の電気出
力を得ることができる。Therefore, electrode 312-electrode 313, electrode 312-electrode 3
If the electrical output between the 14 is processed differentially, twice the electrical output can be obtained.
この場合、管体１、渦発生体２と容器３３は一体構造に
作られているので、構造がシンプルになり、頑丈で、小
型軽量に作ることができ、安価なものが得られる。In this case, since the tube body 1, the vortex generator 2, and the container 33 are made in one piece, the structure is simple, strong, small and lightweight, and an inexpensive product can be obtained.
特に、本実施例の場合は、管体１、渦発生体２と容器３
４を一体に、たとえば精密鋳造等により作り、その後、
封着体３２でもって、検出センサ部３１を封着して力検
出部５を構成することができ、第２図に示すごとく、管
体１と渦発生体２千力検出部３を別体で作り、溶接３４
等により一体的に構成したものに比して、更に安価で頑
丈なものが得られる。In particular, in the case of this embodiment, the pipe body 1, the vortex generator 2 and the container 3
4 are made integrally, for example, by precision casting, and then,
The force detection unit 5 can be constructed by sealing the detection sensor unit 31 with the sealing body 32, and as shown in FIG. Made with and welded 34
It is possible to obtain a product that is cheaper and more durable than an integrally constructed product.
而も、被測定流体に接する部分にネ・いては、構成部品
間に隙間や窪みがないので、腐食性流体に対して、耐食
性のよいものが得られる。Moreover, since there are no gaps or depressions between the component parts in the part that comes into contact with the fluid to be measured, a product with good corrosion resistance against corrosive fluids can be obtained.
また、硬質プラスチック等の高分子材料で、管体１と渦
発生体２と封着体３２を構成すれば、検出センサ部３１
を封着して、一体成形で作ることができ、製作が更にき
わめて容易なものが得られる。Furthermore, if the tube body 1, vortex generator 2, and sealing body 32 are made of a polymeric material such as hard plastic, the detection sensor section 31
It can be made by sealing and integrally molding, and it can be made very easily.
また、プラスチック等の高分子材料を用いると、被測定
流体と接する部分の表面あらさを金属材料の場合に比し
て、更になめらかなものが得られ、食品等の流速流量の
計測に好適ｉものが得られる。In addition, when using a polymeric material such as plastic, the surface roughness of the part that comes into contact with the fluid to be measured can be made smoother than when using a metal material, making it suitable for measuring the flow velocity of foods, etc. is obtained.
しかも、高分子材料は一般に耐食性にすぐれ、特に、４
ふつ化エチレン樹脂等を用いれば、金属材料では得られ
ない高耐食性を有するものが得られる。Moreover, polymeric materials generally have excellent corrosion resistance, especially 4
If fluorinated ethylene resin or the like is used, a material with high corrosion resistance that cannot be obtained with metal materials can be obtained.
更に、本実施例に釦いては、図に示す如く、円筒状の容
器を、被測定流体の流れる管体１内に渦発生体による渦
発生を乱さない程度に突出させた。Furthermore, in this embodiment, as shown in the figure, the cylindrical container was made to protrude into the tube body 1 through which the fluid to be measured flows, to the extent that it does not disturb the vortex generation by the vortex generator.
一般に、カルマン渦を利用した流速流量測定装置におい
ては、管路内にカルマン渦を効率よく発生させるために
は、最も適した一様断面形状の柱状の渦発生体を管路に
挿入するのが一般的であり、渦発生体と異なる断面形状
を有する、たとえば第１図実施例の容器の如き、突出部
分を設けることは、むしろ避ける事が従来は一般的であ
った。Generally, in a flow rate measuring device that uses Karman vortices, in order to efficiently generate Karman vortices in the pipe, it is recommended to insert a columnar vortex generator with the most suitable uniform cross-sectional shape into the pipe. Conventionally, it has been common practice to avoid providing a protruding portion, such as in the case of the container shown in FIG. 1, which has a cross-sectional shape different from that of the vortex generator.
而るに、本願発明者等による実験によれば、多少の突出
部は渦発生体２による渦発生の効果には大きな影響を及
ぼさないことが分った。However, according to experiments conducted by the inventors of the present application, it has been found that a slight protrusion does not significantly affect the effect of vortex generation by the vortex generator 2.
この結果、力検出部３を突出部内に配置し管体１の直径
の範囲内に設置することができるので、流速流量測定装
置全体の構成を更に、コンパクトにできる。As a result, the force detection section 3 can be disposed within the protrusion and installed within the diameter of the tube body 1, so that the overall configuration of the flow rate measuring device can be made more compact.
而も、検出感度を高くすることができる。Moreover, detection sensitivity can be increased.
第３図は本発明の他の実施例の構成説明図で、容器３３
と同一の外形形状をなす突出部３３ａを渦発生体２をは
さんで、容器３３と対称の位置に設けたもので、管体１
の内径内での突出部の形を対称形にして、容器３３の突
出による、カルマン渦の発生の乱れをできるだけ少くす
るようにしたものである。FIG. 3 is an explanatory diagram of the configuration of another embodiment of the present invention, in which a container 33
A protrusion 33a having the same external shape as the tube body 1 is provided at a position symmetrical to the container 33 with the vortex generator 2 in between.
The shape of the protrusion within the inner diameter of the container 33 is made symmetrical to minimize disturbance in the generation of Karman vortices due to the protrusion of the container 33.
第４図は本発明の別の実施例の構成説明図で、本実施例
に釦いては、力検出部３を渦発生体２をはさんで管体壁
側に２個対称に設けたもので、検出器の重畳化或は両刃
検出部３からの信号を演算、たとえば加算等を自由に行
えるようにしたものである。FIG. 4 is a configuration explanatory diagram of another embodiment of the present invention. In this embodiment, two force detection units 3 are provided symmetrically on the tube wall side with the vortex generator 2 in between. In this embodiment, the detectors can be superimposed or the signals from the double-edged detector 3 can be freely calculated, for example, added.
第５図Ａ、Ｂ、Ｃは本発明の他の実施例の構成説明図で
、Ａは正面図、ＢはＡの要部平面図、ＣはＢの要部構成
説明図である。5A, B, and C are diagrams illustrating the configuration of another embodiment of the present invention, in which A is a front view, B is a plan view of the main part of A, and C is a diagram illustrating the configuration of the main part of B. FIG.
本実施例に釦いては、容器３３ｂの外形を渦発生体２と
同一形状とし、検出センサ部３１ｂも相似合形とし、容
器３３ｂに同心台形状に配置し、封着体３２、この場合
はエポキシ樹脂で封着したものである。In this embodiment, the outer shape of the container 33b is the same as that of the vortex generator 2, the detection sensor part 31b is also of a similar shape, and is arranged in a concentric trapezoidal shape on the container 33b. It is sealed with epoxy resin.
な釦、検出センサ部３１ｂはＣ図に示すごとく、台形状
の、この場合はジルコン・チタン酸鉛ＰＺＴよりなる素
子本体３１１ｂと電極３１２ｂ 。As shown in Figure C, the button detection sensor section 31b has a trapezoidal element body 311b made of zircon-lead titanate PZT in this case, and an electrode 312b.
３１３ｂ、３１４ｂよりなる。It consists of 313b and 314b.
電極３１２ｂは蓮台形板状を々し、素子本体３１１ｂの
一面側に設けられている。The electrode 312b has a lotus trapezoidal plate shape and is provided on one side of the element body 311b.
一方、電極３１３ｂ、３１４ｂはそれぞれ第５図Ｃに示
すごとく、梯形をなし、素子本体３１１ｂの他面側に、
渦発生体２の軸心をはさんで流路方向と直角方向に対称
に配置されている。On the other hand, the electrodes 313b and 314b each have a trapezoidal shape as shown in FIG.
They are arranged symmetrically across the axis of the vortex generator 2 in a direction perpendicular to the flow path direction.
このようにすれば、管体１の内径内に突出部のないもの
を得ることができ、而も、力検出部３は管体１の直径範
囲内に配置することができる。In this way, it is possible to obtain a tube 1 without any protrusion within its inner diameter, and the force detection section 3 can be arranged within the diameter range of the tube 1.
なか、前述の実施例に釦いては、素子本体３１１．３１
１ｂはニオブ酸リチウム或はジルコン・チタン酸鉛ＰＺ
Ｔよりなる圧電素子と説明したが、ニオブ酸リチウムや
水晶等の圧電性結晶、或は、ジルコン・チタン酸鉛ＰＺ
Ｔやチタン酸鉛等のセラミック系圧電磁器或は感圧素子
でもよく、要するに圧力を電気信号に変換するものであ
ればよい。Among them, in the above-mentioned embodiment, the element body 311.31
1b is lithium niobate or zircon lead titanate PZ
Although the piezoelectric element was explained as a piezoelectric element made of T, piezoelectric crystals such as lithium niobate and quartz, or zircon lead titanate PZ
It may be a ceramic piezoelectric ceramic such as T or lead titanate, or a pressure sensitive element, as long as it converts pressure into an electrical signal.
渣た、封着体３１はガラスやエポキシ系のものでなく、
セメント系やセラミック系、或は、マイカ等の封着材で
もよく、要するに、渦発生体２に作用する力を検出セン
サ部３１に確実に感厳よく伝達し、電気的に絶縁し、化
学的に安定ｉものであればよい。However, the sealing body 31 is not made of glass or epoxy.
A cement-based, ceramic-based, or mica-based sealing material may be used.In short, the force acting on the vortex generator 2 is reliably and sensitively transmitted to the detection sensor section 31, electrically insulated, and chemically insulated. It is sufficient if it is stable.
以上説明したように、本発明に釦いては、管体と渦発生
体と容器を一体構造として、力検出部３を管体１の直径
範囲内に配置するようにした。As explained above, according to the present invention, the tube body, the vortex generator, and the container are made into an integral structure, and the force detection section 3 is arranged within the diameter range of the tube body 1.
この結果、構成はシンプルにｉす、頑丈、安価で、小型
化、軽量化がはかれ、耐食性のよい流速流量測定装置を
実現することができる。As a result, it is possible to realize a flow rate measuring device that has a simple configuration, is sturdy, inexpensive, compact, lightweight, and has good corrosion resistance.
第１図Ａ、Ｂ、Ｃは本発明の一実施例の構成説明図で、
Ａは縦断面図、Ｂは側断面図、Ｃは要部構成説明図であ
る。
第２〜４図は本発明の他の実施例の構成説明図で、第５
図Ａ 、Ｂ 、Ｃは本発明の他の実施例の構成説明図で
、Ａは正面図、ＢはＡの要部平面図、ＣはＢの要部構成
説明図である。
１・・・管体、２・・・渦発生体、３・・・力検出部、
３１・・・検出センサ部、３２・・・封着体、３３・・
・容器。FIGS. 1A, B, and C are configuration explanatory diagrams of an embodiment of the present invention,
A is a longitudinal cross-sectional view, B is a side cross-sectional view, and C is an explanatory diagram of the main part configuration. 2 to 4 are configuration explanatory diagrams of other embodiments of the present invention.
Figures A, B, and C are diagrams illustrating the configuration of other embodiments of the present invention, in which A is a front view, B is a plan view of the main part of A, and C is a diagram illustrating the configuration of the main part of B. DESCRIPTION OF SYMBOLS 1... Pipe body, 2... Vortex generator, 3... Force detection part,
31... Detection sensor section, 32... Sealing body, 33...
·container.
Claims (1)
して流速流量を測定する流速流量測定装置に釦いて、管
路に挾持される管体と、該管体に直角に挿入され該管体
に一端が固定された渦発生体と、該渦発生体の他端に固
定され検出センサ部と該検出センサ部を内包する容器と
該容器に前記検出センサ部を封着固定する封着体とを具
える力検出部とを具備し該力検出部が前記管体の直径範
囲内に配置され、かつ、前記管体と渦発生体と容器とが
一体成形されたことを特徴とする流速流量測定装置。 ２ 管体と渦発生体と容器と封着体とが一体成形された
ことを特徴とする特許請求の範囲第１項記載の流速流量
測定装置。[Claims] 1. A flow rate measuring device that measures the flow rate by detecting the alternating force acting on the vortex generating body due to the Karman vortex, is connected to a pipe body held in a pipe, and a pipe perpendicular to the pipe body. a vortex generator inserted into the tube and having one end fixed to the tube; a detection sensor unit fixed to the other end of the vortex generator; a container containing the detection sensor unit; and a container with the detection sensor unit sealed to the container. a force detecting section having a sealing body for fixing, the force detecting section being disposed within a diameter range of the tube, and the tube, the vortex generator, and the container being integrally molded. A flow rate measuring device characterized by: 2. The flow rate measuring device according to claim 1, wherein the tube, the vortex generator, the container, and the sealing body are integrally molded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53069632A JPS5832334B2 (en) | 1978-06-09 | 1978-06-09 | Flow velocity flow measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53069632A JPS5832334B2 (en) | 1978-06-09 | 1978-06-09 | Flow velocity flow measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS54161357A JPS54161357A (en) | 1979-12-20 |
| JPS5832334B2 true JPS5832334B2 (en) | 1983-07-12 |
Family
ID=13408420
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP53069632A Expired JPS5832334B2 (en) | 1978-06-09 | 1978-06-09 | Flow velocity flow measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5832334B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0628657U (en) * | 1992-08-28 | 1994-04-15 | ヤン リ−シャン | Weigh scale using hydraulic pressure transmission means |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0110321B1 (en) * | 1982-11-25 | 1988-09-07 | Oval Engineering Co., Ltd. | Vortex flow meter |
| JPS61139422U (en) * | 1985-02-20 | 1986-08-29 |
-
1978
- 1978-06-09 JP JP53069632A patent/JPS5832334B2/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0628657U (en) * | 1992-08-28 | 1994-04-15 | ヤン リ−シャン | Weigh scale using hydraulic pressure transmission means |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS54161357A (en) | 1979-12-20 |
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