JPH0777443A - Flow measuring device - Google Patents
Flow measuring deviceInfo
- Publication number
- JPH0777443A JPH0777443A JP5246376A JP24637693A JPH0777443A JP H0777443 A JPH0777443 A JP H0777443A JP 5246376 A JP5246376 A JP 5246376A JP 24637693 A JP24637693 A JP 24637693A JP H0777443 A JPH0777443 A JP H0777443A
- Authority
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- Prior art keywords
- flow
- tube
- flow velocity
- laminar
- fluid
- 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.)
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- Measuring Volume Flow (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、測定対象管内の流体の
流量を測定する流量測定装置に関し、特に、レーザドッ
プラ流速計（Ｌａｓｅｒ Ｄｏｐｐｌｅｒ Ｖｅｌｏｃ
ｉｍｅｔｅｒ：以下ＬＤＶと略記する）などを使用した
レーザ方式の流量測定装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow rate measuring device for measuring the flow rate of a fluid in a pipe to be measured, and more particularly to a laser Doppler velocity meter (Laser Doppler Veloc).
The present invention relates to a laser type flow rate measuring device using an imager (hereinafter abbreviated as LDV).
【０００２】[0002]
【従来の技術】従来、この種の流量測定装置は、燃料
計、ショックアブソーバ、プラント設備の配管等を流れ
る燃料、オイル、原料などの流体の種類を問わず、過渡
的な流量の変化を、瞬時瞬時に知りたい場合などに使用
されている。2. Description of the Related Art Conventionally, a flow rate measuring device of this type is capable of changing a transient flow rate irrespective of the type of fluid such as fuel, oil and raw material flowing through a fuel gauge, a shock absorber, piping of plant equipment, etc. It is used when you want to know instantly.
【０００３】図２は、従来の流量測定装置の一例を示す
模式図である。レーザ方式の流量測定装置２０は、測定
対象管３０内を流れる流体の流速を、ＬＤＶ２１により
測定し、その測定点の流速に断面積を乗じて測定対象管
３０の流量を演算していた。ＬＤＶ２１は、２本の交差
した照射光によって形成される干渉縞を通過する流体の
流速を測定する流速計である。このＬＤＶ２１は、非接
触で流速を測定するために、測定対象管内の場を乱すこ
となく、流体の温度、圧力変化などの影響を受けずに、
低損失かつ高応答により流速を測定することができる。
また、測定周波数をシフトすることにより、速度方向の
判別ができるために、反転流などの測定が可能である。FIG. 2 is a schematic view showing an example of a conventional flow rate measuring device. The laser type flow rate measuring device 20 measures the flow velocity of the fluid flowing in the measurement target pipe 30 by the LDV 21, and multiplies the flow velocity at the measurement point by the cross-sectional area to calculate the flow rate of the measurement target pipe 30. The LDV 21 is a velocity meter that measures the flow velocity of the fluid passing through the interference fringe formed by the two intersecting irradiation lights. Since the LDV 21 measures the flow velocity in a non-contact manner, it does not disturb the field in the pipe to be measured and is not affected by changes in the temperature and pressure of the fluid,
The flow velocity can be measured with low loss and high response.
Moreover, since the velocity direction can be determined by shifting the measurement frequency, it is possible to measure the reverse flow.
【０００４】[0004]
【発明が解決しようとする課題】しかし、前述した従来
の流量測定装置２０では、ＬＤＶ２１を使用して測定対
象管３０内を流れる流体の流速を測定する場合に、測定
対象管３０内の１点を測定しており、速度分布の相違に
よって測定精度が悪くなるので、各流速に対応する流量
を事前にキャリブレーションしておく必要がある。この
ために、使い勝手を重視して、流れの状態が変化したと
きに、すぐにキャリブレーションでき、しかも、液体慣
性などによる負荷の影響を受けないように、図２に示す
ように、流量計２２をバルブ２３，２４によって切り換
えて、直列に配置するような構造にしておく必要があっ
た。However, in the above-mentioned conventional flow rate measuring device 20, when the flow velocity of the fluid flowing in the measuring object pipe 30 is measured by using the LDV 21, one point in the measuring object pipe 30 is measured. Since the measurement accuracy is deteriorated due to the difference in velocity distribution, it is necessary to calibrate the flow rate corresponding to each flow velocity in advance. For this reason, with emphasis on usability, when the flow condition changes, calibration can be performed immediately, and as shown in FIG. It was necessary to have a structure in which the valves were switched by valves 23 and 24 so as to be arranged in series.
【０００５】また、このようにキャリブレーションを行
った場合であっても、例えば、流速１ｍ／ｓｅｃ程度の
エンジンオイルを測定したときに、乱流の影響を受け
て、５％程度の測定誤差が生ずる場合があった。測定対
象管内の流体が層流の場合には、速度分布が放物線とな
り、中央軸上の最大流速を測定すれば、その１／２が平
均流速となることが知られている。この流体が乱流にな
ると、前記関係が成り立たなくなり、１点の流速を測定
しても、流速分布が一定でないので、平均流速を簡単に
求めることができない。平均流速を求めるのに、１つの
代表値によって換算してしまうと、測定誤差が５％では
収まらなくなってしまう。したがって、細かい速度範囲
ごとに、キャリブレーションが必要となり、測定に手間
がかかるという問題があった。Even when the calibration is performed in this way, for example, when measuring engine oil having a flow velocity of about 1 m / sec, there is a measurement error of about 5% due to the influence of turbulence. Sometimes it happened. It is known that when the fluid in the pipe to be measured is a laminar flow, the velocity distribution becomes a parabola, and if the maximum flow velocity on the central axis is measured, 1/2 of that is the average flow velocity. When this fluid becomes turbulent, the above relationship does not hold and even if the flow velocity at one point is measured, the average flow velocity cannot be easily obtained because the flow velocity distribution is not constant. If one representative value is used to calculate the average flow velocity, the measurement error of 5% will not be met. Therefore, there is a problem in that calibration is required for each fine speed range, and measurement takes time.
【０００６】一方、層流流量計のように、管内を層流状
態で流れている流体の流速と前後の差圧が比例関係にあ
ることを利用して流量を検出する方法もあるが、原理的
に差圧がでないと測定できないので、圧力損失が大きく
なるという問題がある。On the other hand, like a laminar flow meter, there is also a method of detecting the flow rate by utilizing the fact that the flow velocity of the fluid flowing in a laminar state in the pipe and the differential pressure before and after are in a proportional relationship. Therefore, there is a problem that pressure loss becomes large because measurement cannot be performed unless there is a differential pressure.
【０００７】本発明の目的は、前述の課題を解決して、
キャリブレーション用の流量計を備えることなく、流体
の粘度、温度、流速などの影響を受けずに、高応答かつ
低損失で流量測定ができるレーザ方式の流量測定装置を
提供することである。The object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide a laser type flow rate measuring device capable of performing flow rate measurement with high response and low loss without being affected by fluid viscosity, temperature, flow velocity and the like without providing a flow meter for calibration.
【０００８】[0008]
【課題を解決するための手段】前記課題を解決するため
に、本発明による流量測定装置の第１の解決手段は、測
定対象管内の流体を分岐させて、各々臨界レイノルズ数
以下とする複数の層流化領域を備え、その流体を層流化
する層流化手段（１１）と、前記層流化手段の少なくと
も一つの層流化領域の少なくとも一点の流速を測定する
流速測定手段（１３）と、前記流速測定手段により測定
した流速及び前記層流化領域の総断面積から前記測定対
象管の流量を演算する流量演算手段（１４）とを含む構
成としてある。In order to solve the above problems, the first solution of the flow rate measuring device according to the present invention is to divide a fluid in a pipe to be measured into a plurality of fluids each having a critical Reynolds number or less. Laminarization means (11) having a laminarization region for laminarizing the fluid, and flow velocity measuring means (13) for measuring the flow velocity at at least one point in at least one laminarization region of the laminarization means. And a flow rate calculating means (14) for calculating the flow rate of the pipe to be measured from the flow velocity measured by the flow velocity measuring means and the total cross-sectional area of the laminarization region.
【０００９】第２の解決手段は、第１の解決手段の流量
測定装置において、前記層流化手段の少なくとも上流に
は、その層流化手段の流速を均一にする整流化手段１２
を備えたことを特徴とすることができる。A second solving means is the flow measuring device of the first solving means, wherein at least upstream of the laminarizing means, the rectifying means 12 for making the flow velocity of the laminarizing means uniform.
It can be characterized by having.
【００１０】[0010]
【作用】本発明によれば、測定対象管内の流体は、層流
化手段によって、最大流量時においても細管などの層流
化領域内の流体が層流となるようにしてある。流体の速
度分布は、層流で流れた場合には一定の放物線分布とな
る。したがって、１つの層流化領域内の流速を、ＬＤＶ
等の流速測定手段により測定し、その流速と層流化領域
の総断面積とから流量演算手段によって流量に換算する
ことができる。つまり、層流化領域により流体の流れを
常に層流に保つことによって、流速分布の影響を無視す
ることができる。According to the present invention, the fluid in the pipe to be measured is made laminar by the laminarization means so that the fluid in the laminarization region such as a thin tube becomes a laminar flow even at the maximum flow rate. The velocity distribution of the fluid has a constant parabolic distribution when the fluid flows in a laminar flow. Therefore, the flow velocity in one laminarization region is
The flow rate can be converted to a flow rate by the flow rate calculating means based on the flow rate and the total cross-sectional area of the laminarization region. In other words, the influence of the flow velocity distribution can be ignored by keeping the fluid flow laminar by the laminarization region.
【００１１】[0011]
【実施例】以下、図面等を参照して、実施例について、
さらに詳しくに説明する。図１は、本発明による流量測
定装置の実施例を示す模式図である。この実施例の流量
測定装置１０は、層流管１１と、整流器１２Ａ，１２Ｂ
と、ＬＤＶ１３と、流量演算器１４などから構成されて
いる。EXAMPLES Examples will be described below with reference to the drawings.
This will be described in more detail. FIG. 1 is a schematic diagram showing an embodiment of a flow rate measuring device according to the present invention. The flow rate measuring device 10 of this embodiment includes a laminar flow pipe 11 and rectifiers 12A and 12B.
The LDV 13 and the flow rate calculator 14 are included.
【００１２】層流管１１は、測定対象管３０の流体を層
流にするためのものであり、その流体が分岐して接続さ
れ、各々臨界レイノルズ数以下になる内径の複数の細管
１１−ｉを束ねた構造のものである。細管１１−ｉのう
ちの少なくとも１本は、ＬＤＶ１３による流速測定のた
めに透明な管としてある。The laminar flow pipe 11 is for making the fluid in the pipe 30 to be measured into a laminar flow, and the fluid is branched and connected to each other, and a plurality of thin pipes 11-i each having an inner diameter of not more than the critical Reynolds number. It has a structure of bundling. At least one of the thin tubes 11-i is a transparent tube for measuring the flow velocity by the LDV 13.
【００１３】整流器１２Ａ，１２Ｂは、層流管１１の両
側に配置され、その層流管１１の前後の流速分布の乱れ
を整えるためのものであり、金網、金属格子、多孔板な
どの構造を採用できる。各整流器１２Ａ，１２Ｂは、双
方向の測定を可能にするために、対称の形状にしてあ
る。The rectifiers 12A and 12B are arranged on both sides of the laminar flow pipe 11 to adjust the disturbance of the flow velocity distribution before and after the laminar flow pipe 11, and have a structure such as a wire mesh, a metal grid, and a perforated plate. Can be adopted. Each rectifier 12A, 12B is symmetrically shaped to allow bidirectional measurements.
【００１４】ＬＤＶ１３は、ＬＤＶプローブ１３１と、
レンズ１３２と、リフレクタ１３３と、光ファイバ１３
４などから構成され、層流管１１の透明な１本の細管１
１−ｉの１点の流速を測定するためのものであり、この
ＬＤＶ１３の出力は、流量演算器１４に接続されてい
る。The LDV 13 includes an LDV probe 131,
The lens 132, the reflector 133, and the optical fiber 13
One transparent thin tube 1 of the laminar flow tube 11 composed of 4 etc.
This is for measuring the flow velocity at one point 1-i, and the output of this LDV 13 is connected to the flow rate calculator 14.
【００１５】流量演算器１４は、ＬＤＶ１３によって測
定された１本の細管１１−ｉの流速と、層流管１１を構
成する各細管１１−ｉの断面積及びその本数に基づい
て、流量を演算するためのものである。流量演算器１４
の出力は、不図示のモニタやプリンタに出力される。The flow rate calculator 14 calculates the flow rate based on the flow velocity of one thin tube 11-i measured by the LDV 13, the cross-sectional area of each thin tube 11-i constituting the laminar flow tube 11 and the number thereof. It is for doing. Flow rate calculator 14
Is output to a monitor or printer (not shown).
【００１６】次に、この実施例の流量測定装置１０の動
作を説明する。ポートＡから流れ込んだ流体は、整流器
１２Ａによって整流された後に、層流管１１の各細管１
１−ｉに分岐して、整流器１２Ｂを介して、反対側のポ
ートＢに流れ出る。このときに、整流管１１の各細管１
１−ｉの内径は、測定対象管３０内の流体の粘度、流量
において、各々の管内で臨界レイノルズ数以下となるよ
うに設定してあるので、各細管１１−ｉ内の流れは層流
となる。Next, the operation of the flow rate measuring device 10 of this embodiment will be described. The fluid flowing from the port A is rectified by the rectifier 12A, and then the thin tubes 1 of the laminar flow tube 11 are rectified.
It branches to 1-i and flows out to the port B on the opposite side via the rectifier 12B. At this time, each thin tube 1 of the rectifying tube 11
The inner diameter of 1-i is set so as to be equal to or lower than the critical Reynolds number in each pipe in the viscosity and the flow rate of the fluid in the pipe 30 to be measured, so that the flow in each thin pipe 11-i is a laminar flow. Become.
【００１７】この層流管１１の内の１本の細管１１−ｉ
を流れる流体の１点を、ＬＤＶ１３によって測定する。
層流で流れる流体は、細管１１−ｉ内で速度分布が一定
であるので、測定した流速と細管１１−ｉの内径及び本
数に基づいて、流量演算器１４によって流量を演算する
ことができる。One of the laminar flow tubes 11 is a thin tube 11-i.
One point of the fluid flowing through is measured by LDV13.
Since the velocity distribution of the fluid flowing in the laminar flow is constant in the thin tube 11-i, the flow rate can be calculated by the flow rate calculator 14 based on the measured flow rate, the inner diameter of the thin tube 11-i, and the number thereof.
【００１８】次に、具体的な製造例に基づいて、さらに
具体的に説明する。層流管１１として、細管１１−ｉの
内半径ｒ＝２ｍｍ＝２×１０-3ｍ、本数ｎ＝２５本のも
のを用い、流体として、動粘度ν＝１０ｃｓｔ＝１０-5
ｍ2 ／ｓ，密度ρ＝０．８ｇ／ｃｍ3 ＝８００ｋｇ／ｍ
3 のもの、具体的には、エンジンオイルを用いた。最大
流速４８０〔ｌ／ｈ〕＝１３３．３×１０-6ｍ3 ／ｓの
ときの流速ｖMAX は、ｖMAX ＝１３３．３×１０-6／
〔（２×１０-3）×π×２５〕＝０．４２５ｍ／ｓとな
る。したがって、そのときのレイノルズ数Ｒｅは、Ｒｅ
＝２ｒｖMAX ／ν＝２×２×１０-3×０．４２５／１０
-5＝１７０となり、臨界レイノルズ数２３２０に対し
て、十分に小さいので、細管１１−ｉ内の流れを層流に
保つことができる。Next, a more specific description will be given based on a specific manufacturing example. As the laminar flow tube 11, a thin tube 11-i having an inner radius r = 2 mm = 2 × 10 −3 m and the number n = 25 is used, and the fluid has a kinematic viscosity ν = 10 cst = 10 −5.
m 2 / s, density ρ = 0.8 g / cm 3 = 800 kg / m
No. 3 , specifically, engine oil was used. When the maximum flow velocity is 480 [l / h] = 133.3 × 10 −6 m 3 / s, the flow velocity v MAX is v MAX = 133.3 × 10 −6 /
[(2 × 10 −3 ) × π × 25] = 0.425 m / s. Therefore, the Reynolds number Re at that time is Re
= 2rv MAX / ν = 2 × 2 × 10 −3 × 0.425 / 10
-5 = 170, which is sufficiently smaller than the critical Reynolds number 2320, so that the flow in the thin tube 11-i can be kept laminar.
【００１９】また、層流管１１は、その長さＬがＬＤＶ
１３の測定点から前後にそれぞれ６０ｒに設定してあ
る。この長さＬは、乱流で流れ込んだ流体が層流に達す
るのに十分な長さである。従って、Ｌ＝０．２４ｍであ
るから、圧力損失Δｐは、Δｐ＝８ＬνρｖMAX ／ｒ2
＝８×０．２４×８００×０．４２５／（２×１０-3）
2 ＝１６３２Ｐａとなる。この圧力損失Δｐは、十分に
小さい値であるので、トランジェント特性に与える影響
はほとんど無いと考えてよい。The length L of the laminar flow pipe 11 is LDV.
It is set to 60r before and after the 13 measurement points. The length L is long enough for the turbulent fluid to reach the laminar flow. Therefore, since L = 0.24 m, the pressure loss Δp is Δp = 8Lνρv MAX / r 2
= 8 × 0.24 × 800 × 0.425 / (2 × 10 −3 )
2 = 1632 Pa. Since this pressure loss Δp is a sufficiently small value, it can be considered that there is almost no effect on the transient characteristics.
【００２０】以上説明した実施例に限定されず、種々の
変形や変更が可能であって、それらも本発明に含まれ
る。例えば、層流化手段として、管径の細い円管を例に
して説明したが、各細管の断面が６角形のハニカム構造
をしたものや、隙間の狭い平板を多数配置した構造であ
ってもよい。The present invention is not limited to the embodiments described above, and various modifications and changes are possible, which are also included in the present invention. For example, as the laminarization means, a circular tube having a small tube diameter has been described as an example, but a honeycomb structure in which each thin tube has a hexagonal cross section or a structure in which a large number of flat plates with narrow gaps are arranged may be used. Good.
【００２１】また、層流化領域は、全て同じ形状である
必要はなく、全体として層流の条件が整っていればよ
い。例えば、流速を測定する透明な１つの細管と、球体
を詰めた大きな１つの領域に分けてもよい。この層流化
領域は、測定対象管と等価でなくてもよく、入口と出口
とが連続的に流れるようにすればよい。この場合に、細
管の本数を多くすれば、圧力損失を小さくすることがで
きる。Further, the laminarized regions need not all have the same shape, and the laminar flow conditions may be satisfied as a whole. For example, it may be divided into one transparent thin tube for measuring the flow velocity and one large area filled with spheres. This laminarization region does not have to be equivalent to the pipe to be measured, and it is sufficient that the inlet and the outlet flow continuously. In this case, the pressure loss can be reduced by increasing the number of thin tubes.
【００２２】さらに、複数に分割した層流化領域は、流
速を測定する１つの領域を選んで、予めキャリブレーシ
ョンしておけばよく、いずれの１つを選んでもよいし、
任意の複数個の領域を選んで測定したり又は全ての領域
を測定して、平均するようにしてもよい。Further, for the laminarized region divided into a plurality of regions, one region for measuring the flow velocity may be selected and calibrated in advance, and any one of them may be selected.
An arbitrary plurality of areas may be selected and measured, or all areas may be measured and averaged.
【００２３】[0023]
【発明の効果】以上詳しく説明したように、本発明によ
れば、細管等の層流化領域により流体を層流にしている
ために、キャリブレーション用の流量計が必要ないう
え、臨界レイノルズ数以下であるので、流体の粘度、温
度、流量等の影響をうけない。また、ＬＤＶ流量計など
の流速測定手段によって流速を測定しているので、高応
答かつ低損失により流量測定ができ、過渡流量測定時に
おける測定系に与える影響が少なくすることができると
ともに、両方向の流量測定ができる。As described in detail above, according to the present invention, since the fluid is made into a laminar flow by the laminarization region such as a thin tube, a flowmeter for calibration is not necessary and the critical Reynolds number is required. Since it is the following, it is not affected by the viscosity, temperature, flow rate, etc. of the fluid. Further, since the flow velocity is measured by the flow velocity measuring means such as an LDV flow meter, the flow rate can be measured with high response and low loss, and the influence on the measurement system during transient flow rate measurement can be reduced, and in both directions. Flow rate can be measured.
【図面の簡単な説明】[Brief description of drawings]
【図１】本発明による流量測定装置の実施例を示す模式
図である。FIG. 1 is a schematic view showing an embodiment of a flow rate measuring device according to the present invention.
【図２】従来の流量測定装置の一例を示す模式図であ
る。FIG. 2 is a schematic view showing an example of a conventional flow rate measuring device.
１０ 流量測定装置 １１ 層流管 １１−ｉ 細管 １２Ａ，１２Ｂ 整流器 １３ ＬＤＶ １４ 流量演算器 10 Flow Rate Measuring Device 11 Laminar Flow Tube 11-i Thin Tube 12A, 12B Rectifier 13 LDV 14 Flow Rate Calculator
Claims (2)
臨界レイノルズ数以下とする複数の層流化領域を備え、
その流体を層流化する層流化手段と、 前記層流化手段の少なくとも一つの層流化領域の少なく
とも一点の流速を測定する流速測定手段と、 前記流速測定手段により測定した流速及び前記層流化領
域の総断面積から前記測定対象管の流量を演算する流量
演算手段とを含む流量測定装置。1. A plurality of laminarization regions each of which divides a fluid in a pipe to be measured and has a critical Reynolds number or less,
Laminarization means for laminarizing the fluid, flow velocity measuring means for measuring the flow velocity at at least one point of at least one laminarization region of the laminarization means, flow velocity measured by the flow velocity measuring means and the layer A flow rate measuring device including a flow rate calculating means for calculating the flow rate of the pipe to be measured from the total cross-sectional area of the flow region.
て、 前記層流化手段の少なくとも上流には、その層流化手段
の流速を均一にする整流化手段を備えたことを特徴とす
る流量測定装置。2. The flow rate measuring device according to claim 1, wherein at least an upstream of the laminarization means is provided with a rectifying means for uniformizing a flow velocity of the laminarization means. measuring device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5246376A JPH0777443A (en) | 1993-09-07 | 1993-09-07 | Flow measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5246376A JPH0777443A (en) | 1993-09-07 | 1993-09-07 | Flow measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0777443A true JPH0777443A (en) | 1995-03-20 |
Family
ID=17147627
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5246376A Pending JPH0777443A (en) | 1993-09-07 | 1993-09-07 | Flow measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0777443A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106920439A (en) * | 2017-04-21 | 2017-07-04 | 三峡大学 | A kind of reynolds test instrument and experimental technique |
| CN109855691A (en) * | 2019-01-14 | 2019-06-07 | 中国计量大学 | A kind of differential type laminar flow measurement method and device |
| CN112438600A (en) * | 2019-09-03 | 2021-03-05 | 弗兰卡凯菲马斯池因股份公司 | Beverage preparation device with milk system |
| WO2023276837A1 (en) * | 2021-07-01 | 2023-01-05 | Dic株式会社 | Specific resistance value adjustment device and specific resistance value adjustment method |
-
1993
- 1993-09-07 JP JP5246376A patent/JPH0777443A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106920439A (en) * | 2017-04-21 | 2017-07-04 | 三峡大学 | A kind of reynolds test instrument and experimental technique |
| CN109855691A (en) * | 2019-01-14 | 2019-06-07 | 中国计量大学 | A kind of differential type laminar flow measurement method and device |
| CN112438600A (en) * | 2019-09-03 | 2021-03-05 | 弗兰卡凯菲马斯池因股份公司 | Beverage preparation device with milk system |
| CN112438600B (en) * | 2019-09-03 | 2022-11-22 | 弗兰卡凯菲马斯池因股份公司 | Beverage preparation device with milk system |
| WO2023276837A1 (en) * | 2021-07-01 | 2023-01-05 | Dic株式会社 | Specific resistance value adjustment device and specific resistance value adjustment method |
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