JPH0360048B2 - - Google Patents
Info
- Publication number
- JPH0360048B2 JPH0360048B2 JP58229684A JP22968483A JPH0360048B2 JP H0360048 B2 JPH0360048 B2 JP H0360048B2 JP 58229684 A JP58229684 A JP 58229684A JP 22968483 A JP22968483 A JP 22968483A JP H0360048 B2 JPH0360048 B2 JP H0360048B2
- Authority
- JP
- Japan
- Prior art keywords
- fluid passage
- partition plate
- flow rate
- fluid
- flow
- 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 - Lifetime
Links
- 239000012530 fluid Substances 0.000 claims description 43
- 238000005192 partition Methods 0.000 claims description 29
- 238000001514 detection method Methods 0.000 claims description 7
- 238000006243 chemical reaction Methods 0.000 claims description 5
- 238000004891 communication Methods 0.000 claims description 2
- 239000007788 liquid Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
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
- G01F1/34—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 measuring pressure or differential pressure
- G01F1/36—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 measuring pressure or differential pressure the pressure or differential pressure being created by the use of flow constriction
- G01F1/38—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 measuring pressure or differential pressure the pressure or differential pressure being created by the use of flow constriction the pressure or differential pressure being measured by means of a movable element, e.g. diaphragm, piston, Bourdon tube or flexible capsule
- G01F1/383—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 measuring pressure or differential pressure the pressure or differential pressure being created by the use of flow constriction the pressure or differential pressure being measured by means of a movable element, e.g. diaphragm, piston, Bourdon tube or flexible capsule with electrical or electro-mechanical indication
-
- 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
- G01F1/28—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 by drag-force, e.g. vane type or impact flowmeter
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
Description
【発明の詳細な説明】
＜産業上の利用分野＞
本発明は、流体通路内を流れる気体や液体等の
流量を検出するための流量計に関し、特に電子機
器等の内部に形成された小径の流体通路内の流量
を検出し、応答性の高い流量制御を行なう場合に
適用して有用なものである。[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a flow meter for detecting the flow rate of gas, liquid, etc. flowing in a fluid passage, and particularly to a flow meter for detecting the flow rate of gas, liquid, etc. flowing in a fluid passage. This is useful when detecting the flow rate in a fluid passage and controlling the flow rate with high responsiveness.
＜背景技術とその問題点＞
従来、流体通路内を流れる気体や液体等の流量
を検出するための流量計として、上記流体通路の
一部を例えばオリフイスやノズル等の絞りによつ
て縮径し、この絞りにより生ずる静圧の変化すな
わち差圧を検出し、上記流体通路に流れる流体の
流量を間接的に測定するようになした差圧流量計
が用いられている。<Background technology and its problems> Conventionally, as a flow meter for detecting the flow rate of gas, liquid, etc. flowing in a fluid passage, a part of the fluid passage is reduced in diameter by, for example, a restriction such as an orifice or a nozzle. A differential pressure flow meter is used that detects a change in static pressure, that is, a differential pressure, caused by this restriction, and indirectly measures the flow rate of fluid flowing through the fluid passage.
ところで、このような差圧流量計は、例えば、
各種電子機器において磁気テープ等を所謂エアシ
ユーテイング方式を用いて装着するための磁気テ
ープの自動供給装置等に用いようとした場合に
は、上記絞りを構成するオリフイスやノズル等の
所謂一次装置に加えて上記差圧を測定するための
所謂二次装置を設ける必要があり、構造が極めて
大型であるという欠点がある。 By the way, such a differential pressure flowmeter is, for example,
When attempting to use an automatic magnetic tape feeding device for mounting magnetic tape, etc. in various electronic devices using the so-called air shunting method, so-called primary devices such as orifices and nozzles that make up the above-mentioned aperture are required. In addition, it is necessary to provide a so-called secondary device for measuring the differential pressure, which has the disadvantage that the structure is extremely large.
また、このような差圧流量計を用いた場合には
上記絞りによつて流体の流れが乱れてしまい、こ
の絞り部分の近傍位置で上述した磁気テープ等の
エアシユーテイング動作を行なつた場合に、この
流体の乱れによつて、上記磁気テープを好適に装
着操作し得ないという欠点がある。 In addition, when such a differential pressure flowmeter is used, the flow of fluid is disturbed by the above-mentioned restriction, and the above-mentioned air shunting operation of the magnetic tape etc. is performed at a position near the restriction. In some cases, this fluid turbulence makes it impossible to properly mount the magnetic tape.
また、さらに上記従来の差圧流量計は、上記二
次装置を必要とするために高価なものとなつてし
まう。 Further, the conventional differential pressure flowmeter described above becomes expensive because it requires the secondary device described above.
＜発明の目的＞
そこで本発明は、上述した如き実情に鑑み、極
めて小型の構成を採り得るとともに整流効果を有
し流体の流れを乱すことのない安価な流量計を提
供することを目的とする。<Object of the invention> In view of the above-mentioned circumstances, it is an object of the present invention to provide an inexpensive flow meter that can have an extremely compact configuration, has a rectifying effect, and does not disturb the flow of fluid. .
＜発明の概要＞
すなわち本発明は、上述した目的を達成するた
めに、多数の流通孔が形成された２つの機械−電
気変換素子を流体の流れの方向に重ね合わせて流
体通路を仕切る仕切板を形成し、上記流体通路内
を流れる流体の圧力による上記２つの機械−電気
変換素子の変形によりそれぞれ得られる検出信号
に基づく電位差によつて上記流体通路内の流量を
測定するようにしたものである。<Summary of the Invention> In other words, in order to achieve the above-mentioned object, the present invention provides a partition plate that partitions a fluid passage by overlapping two mechanical-electrical conversion elements in which a large number of communication holes are formed in the direction of fluid flow. , and the flow rate in the fluid passage is measured by a potential difference based on a detection signal obtained by deformation of the two mechanical-electric conversion elements due to the pressure of the fluid flowing in the fluid passage. be.
＜実施例＞
以下、本発明の具体的な実施例を図面に従つて
詳細に説明する。<Examples> Hereinafter, specific examples of the present invention will be described in detail with reference to the drawings.
この実施例における流量計は、第１図に示すよ
うに円筒管１によつて形成される流体通路２に配
されており、この流体通路２を流れる圧縮エアの
流量を測定するために設けられたものである。こ
の流量計は第２図及び第３図にも示すように、上
記流体通路２を仕切る如く設けられる仕切板３が
機械−電気変換素子となる二枚の圧電素子４，５
を貼り合せ上記流体通路２の形状に応じて円盤状
に形成されたものである。上記各圧電素子４，５
は互いに異なつた分極方向を有してなるものであ
り、この仕切板３が上記流体通路２を流れる圧縮
エアの圧力を受けて撓んだ際に、互いの貼り合せ
面を中立面として、一方の圧電素子４が短縮する
とともに他方に圧電素子５が伸張する如くなり、
この仕切板３の両側面間に電圧を生じるようにな
つている。 The flow meter in this embodiment is arranged in a fluid passage 2 formed by a cylindrical pipe 1 as shown in FIG. 1, and is provided to measure the flow rate of compressed air flowing through this fluid passage 2. It is something that As shown in FIGS. 2 and 3, in this flowmeter, a partition plate 3 provided to partition the fluid passage 2 has two piezoelectric elements 4 and 5 serving as mechanical-electric conversion elements.
are bonded together to form a disk shape according to the shape of the fluid passage 2. Each of the above piezoelectric elements 4, 5
have different polarization directions, and when the partition plate 3 is bent under the pressure of the compressed air flowing through the fluid passage 2, the bonded surfaces of the partition plates 3 and 3 have different polarization directions. While one piezoelectric element 4 is shortened, the other piezoelectric element 5 is expanded,
A voltage is generated between both sides of the partition plate 3.
また、このように圧電素子４，５を貼り合せて
なる仕切板３には、流通路となる多数の透孔６が
形成されている。これら透孔６は上記仕切板３に
て仕切られる上記流体通路２を連通する如く上記
各圧電素子４，５に穿設されたものであり、仕切
板３の側面の全面に亘つてほぼ均等に分散されて
いる。 Further, in the partition plate 3 formed by pasting the piezoelectric elements 4 and 5 together in this manner, a large number of through holes 6 that serve as flow paths are formed. These through holes 6 are formed in each of the piezoelectric elements 4 and 5 so as to communicate with the fluid passage 2 partitioned by the partition plate 3, and are formed almost evenly over the entire side surface of the partition plate 3. Distributed.
またさらに、上記仕切板３の両側面には表面電
極７，８が配されている。これら表面電極７，８
は上記各透孔６を塞ぐことなく各側面に被着形成
されたものであり、リード線９，１０及び接続端
子１１，１２に接続され、このリード線９，１０
及び接続端子１１，１２を介して互いの表面電極
７，８間の電圧を検出信号として得られるように
なつている。 Furthermore, surface electrodes 7 and 8 are arranged on both sides of the partition plate 3. These surface electrodes 7, 8
is formed on each side surface without blocking each of the through holes 6, and is connected to the lead wires 9, 10 and the connection terminals 11, 12.
The voltage between the surface electrodes 7 and 8 can be obtained as a detection signal via the connection terminals 11 and 12.
また、このような構成の仕切板３は上記円筒管
１に例えばゴム材よりなる円環状の取付体１３を
介して嵌合されるようにして、上記流体通路２に
配されている。 Further, the partition plate 3 having such a structure is disposed in the fluid passage 2 so as to be fitted to the cylindrical tube 1 via an annular attachment body 13 made of, for example, a rubber material.
そして、このように構成した流量計を配した流
体通路２内に圧縮エアが流れると、上記仕切板３
は、第４図に示すように、上記圧縮エアの圧力に
よつて上記流体通路２の上流より下流に向つて押
圧され、湾曲変形することとなる。すると、この
仕切板３を構成する二枚の圧電素子４，５は互い
の貼合せ面を中立面とするようにして上記一方の
圧電素子４が短縮し、他方の圧電素子５が伸張す
ることとなり、上記各表面電極７，８間に電位差
を生じさせる。そこで、これら表面電極７，８間
の電位差を上記リード線９，１０及び接続端子１
１，１２等を介して検出信号として読み取り、上
記仕切板３の湾曲変形量を読取ることにより、上
記仕切板３に加わる圧力を検出し、この圧力より
上記流体通路２に流れる圧縮エアの流量を検出す
ることができる。すなわち、上記流量をＱ、上記
検出信号をΔE、そして上記圧縮エアの単位体積
あたりの重量をγとすると、
（Ｋ：校正試験等によつて得られる比例定数、
ｇ：重量の加速度）
の関係より、流量Ｑの値を上記検出信号ΔEの値
より求めることができる。 When compressed air flows into the fluid passage 2 in which the flow meter configured as described above is arranged, the partition plate 3
As shown in FIG. 4, is pressed from the upstream side to the downstream side of the fluid passage 2 by the pressure of the compressed air, and is deformed into a curve. Then, the two piezoelectric elements 4 and 5 constituting this partition plate 3 have their bonded surfaces set as neutral planes, so that one piezoelectric element 4 shortens and the other piezoelectric element 5 expands. This causes a potential difference between each of the surface electrodes 7 and 8. Therefore, the potential difference between these surface electrodes 7 and 8 is adjusted to the lead wires 9 and 10 and the connection terminal 1.
1, 12, etc., and by reading the amount of bending deformation of the partition plate 3, the pressure applied to the partition plate 3 is detected, and the flow rate of the compressed air flowing into the fluid passage 2 is determined from this pressure. can be detected. That is, if the above flow rate is Q, the above detection signal is ΔE, and the weight per unit volume of the compressed air is γ, then (K: proportionality constant obtained by a calibration test, etc., g: acceleration of weight) Based on the relationship, the value of the flow rate Q can be determined from the value of the detection signal ΔE.
このように本実施例の流量計によれば、上記仕
切板３の変形によつて得られる検出信号より、上
記流体通路２に流れる圧縮エアの流量を速やかに
求めることができる。 As described above, according to the flowmeter of this embodiment, the flow rate of the compressed air flowing into the fluid passage 2 can be quickly determined from the detection signal obtained by the deformation of the partition plate 3.
また、上述の如き仕切板３の形状を小型化する
ことにより小径の流体通路２における流量測定に
も用いることができ、さらに、この仕切板３の変
形量を求めるために大型の二次装置を設ける必要
もない。従つて、この流量計は極めて小型の装置
として構成することができる。そして、複雑な構
成の二次装置を必要としないことから、極めて安
価な装置として得ることができる。 Furthermore, by reducing the size of the partition plate 3 as described above, it can be used to measure the flow rate in a small diameter fluid passage 2, and furthermore, a large secondary device is required to determine the amount of deformation of the partition plate 3. There is no need to provide one. Therefore, this flow meter can be constructed as an extremely compact device. Further, since a secondary device with a complicated configuration is not required, the device can be obtained as an extremely inexpensive device.
さらに、上記仕切板３にほぼ均等に分散して透
孔６を形成したことから、上記圧縮エアの流れが
乱されてしまうこともない。 Furthermore, since the through holes 6 are formed in the partition plate 3 so as to be almost evenly distributed, the flow of the compressed air will not be disturbed.
また、上記実施例では円筒管１内に流量計を配
した場合について述べたが、上述のように小型形
状に形成される流量計は、例えば第５図に示すよ
うな、磁気記録再生装置における磁気テープ１４
の自動供給装置において、上記磁気テープ１４を
テープ送りするための圧縮エアの流量検出用に用
いることができる。この自動供給装置では、上記
磁気テープ１４を回転自在な巻回リール１５に巻
付けた状態で密閉型のエアシユーテングケース１
６に収納し、上記磁気テープ１４をエアシユーテ
ングケース１６の一部に形成された繰出口１７よ
り繰出すようにしたものである。すなわち、上記
繰出口１７に隣接するようにして、流体通路２の
開口部２ａが臨み、この流体通路２より吐出され
る圧縮エアを上記磁気テープ１４が導かれるテー
プ走行路１８内に供給することにより、上記磁気
テープ１４の圧縮エアによるテープ送りを行なう
ようになされている。そして、本発明に係る流量
計は上記流体通路２の開口部２ａ近傍に配されて
おり、上記磁気テープ１４側に吐出される圧縮エ
アの流量を上記磁気テープ１４の近傍位置で検出
することができる。従つて、上記磁気テープ１４
の確実なテープ送りを行なうための圧縮エアの流
量を好適に制御することができる。しかも、この
流量計によつて上記磁気テープ１４側に吐出され
る圧縮エアの流れが乱されてしまうこともないの
で、上記磁気テープ１４の撓み等を生じてしまう
こともなく、円滑なテープ送りを実現することが
できる。 Further, in the above embodiment, the case where the flowmeter is disposed inside the cylindrical tube 1 has been described, but the flowmeter formed in a small shape as described above can be used in a magnetic recording/reproducing device as shown in FIG. 5, for example. magnetic tape 14
The present invention can be used for detecting the flow rate of compressed air for feeding the magnetic tape 14 in an automatic feeding device. In this automatic feeding device, the magnetic tape 14 is wound around a rotatable winding reel 15 in a sealed air-shutting case 1.
6, and the magnetic tape 14 is fed out from a feeding opening 17 formed in a part of an air discharging case 16. That is, the opening 2a of the fluid passage 2 faces adjacent to the outlet 17, and the compressed air discharged from the fluid passage 2 is supplied into the tape running path 18 along which the magnetic tape 14 is guided. Accordingly, the magnetic tape 14 is fed by compressed air. The flow meter according to the present invention is disposed near the opening 2a of the fluid passage 2, and can detect the flow rate of compressed air discharged to the magnetic tape 14 at a position near the magnetic tape 14. can. Therefore, the magnetic tape 14
The flow rate of compressed air can be suitably controlled to ensure reliable tape feeding. Moreover, since the flow of compressed air discharged to the magnetic tape 14 side is not disturbed by this flow meter, the magnetic tape 14 is not bent, etc., and the tape can be fed smoothly. can be realized.
なお、上述した実施例では圧縮エアの流量を検
出するための流量計について述べたが、本発明の
流量計は水等の液体の流量検出を行なう場合にも
用いることができる。 In the above-described embodiment, a flowmeter for detecting the flow rate of compressed air was described, but the flowmeter of the present invention can also be used to detect the flow rate of liquid such as water.
＜発明の効果＞
上述したように、本発明は、流体通路に直接配
置される仕切板を構成する２つの機械−電気変換
素子の変形によりそれぞれ得られる検出信号に基
づく電位差によつて上記流体通路内の流量を測定
するものであるので、流体通路を流れる流体の流
量を直接に且つ速やかに求めることができる。<Effects of the Invention> As described above, the present invention is capable of controlling the fluid passage by using a potential difference based on a detection signal obtained by deformation of two mechanical-electric conversion elements constituting a partition plate disposed directly in the fluid passage. Since the flow rate in the fluid passage is measured, the flow rate of the fluid flowing through the fluid passage can be directly and quickly determined.
そして、上記仕切板の形状を小型にすることに
より小径の流体通路における流量測定にも用いる
ことができ、さらに、大型の二次装置を設ける必
要がない。従つて、この流量計は極めて小型の装
置として構成することができ、電子機器等に実装
することも容易である。 By making the shape of the partition plate small, it can be used to measure the flow rate in a small diameter fluid passage, and there is no need to provide a large secondary device. Therefore, this flowmeter can be configured as an extremely small device and can be easily mounted on electronic equipment and the like.
また、複雑な構成を有する高価な二次装置を必
要としないことから、極めて安価な装置として得
ることができる。 Furthermore, since an expensive secondary device with a complicated configuration is not required, the device can be obtained as an extremely inexpensive device.
またさらに、上記仕切板によつて流体の流れが
乱れてしまうこともなく、この乱れを整えるため
の整流装置等を設ける必要もない。 Furthermore, the flow of the fluid is not disturbed by the partition plate, and there is no need to provide a rectifying device or the like to correct this disturbance.
第１図は本発明に係る流量計の一実施例を示す
概略断面図、第２図は上記流量計の仕切板を示す
概略断面図、第３図は上記仕切板を示す概略正面
図、第４図は上記仕切板が湾曲変形した状態を示
す概略断面図、第５図は上記流量計を磁気テープ
の自動供給装置に用いてなる他の実施例を示す一
部省略平面図である。
２……流体通路、３……仕切板、４，５……圧
電素子、６……透孔、７，８……表面電極。
FIG. 1 is a schematic sectional view showing an embodiment of a flowmeter according to the present invention, FIG. 2 is a schematic sectional view showing a partition plate of the flowmeter, FIG. 3 is a schematic front view showing the partition plate, and FIG. FIG. 4 is a schematic sectional view showing a state in which the partition plate is curved and deformed, and FIG. 5 is a partially omitted plan view showing another embodiment in which the flow meter is used in an automatic magnetic tape feeding device. 2... Fluid passage, 3... Partition plate, 4, 5... Piezoelectric element, 6... Through hole, 7, 8... Surface electrode.
Claims (1)
変換素子を流体の流れの方向に重ね合わせて流体
通路を仕切る仕切板を形成し、上記流体通路内を
流れる流体の圧力による上記２つの機械−電気変
換素子の変形によりそれぞれ得られる検出信号に
基づく電位差によつて上記流体通路内の流量を測
定する流量計。1 Two mechanical-electric conversion elements in which a large number of communication holes are formed are overlapped in the direction of fluid flow to form a partition plate that partitions a fluid passage, and the two machines are controlled by the pressure of the fluid flowing in the fluid passage. - A flow meter that measures the flow rate in the fluid passage by means of a potential difference based on a detection signal obtained by deformation of an electrical transducer element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22968483A JPS60122319A (en) | 1983-12-05 | 1983-12-05 | Flow meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22968483A JPS60122319A (en) | 1983-12-05 | 1983-12-05 | Flow meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60122319A JPS60122319A (en) | 1985-06-29 |
| JPH0360048B2 true JPH0360048B2 (en) | 1991-09-12 |
Family
ID=16896069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22968483A Granted JPS60122319A (en) | 1983-12-05 | 1983-12-05 | Flow meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60122319A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04106627U (en) * | 1991-02-19 | 1992-09-14 | 関西日本電気株式会社 | Liquid flow rate fluctuation detection mechanism |
| DE102018215851B3 (en) * | 2018-09-18 | 2019-09-26 | Siemens Aktiengesellschaft | Pressure or flow cell |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54147864A (en) * | 1978-05-12 | 1979-11-19 | Yokogawa Hokushin Electric Corp | Measuring apparatus of velocity and rate of flow |
-
1983
- 1983-12-05 JP JP22968483A patent/JPS60122319A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54147864A (en) * | 1978-05-12 | 1979-11-19 | Yokogawa Hokushin Electric Corp | Measuring apparatus of velocity and rate of flow |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60122319A (en) | 1985-06-29 |
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