JPS58213214A - Electromagnetic flowmeter - Google Patents

Abstract

PURPOSE:To decrease the winding number of coils and to reduce cost, by burying a pair of reinforcing plates which are formed the section in a circular arc, crossing at right angles to magnetic flux and facing each other in an insulating lining coated on the inside of a measuring pipe by using a magnetic material. CONSTITUTION:A measuring pipe 11 is joined with a flange on the way to a main pipe flowing a fluid to be measured and insulating lining formed by synthetic resin is coated on its inside. A pair of exciting coils 13 wound around a wire in a saddle frame shape is attached facing each other to the outer circumferential face of the pipe 11 with a core and a mount enveloping in the coils 13 and a pair of electrodes 14 is inserted into the central part of an axis direction of the pipe 11 facing each other at the position where the water flowing direction of the pipe 11 is crossed at right angles to the direction of a magnetic flux 5 formed by the coil 3 and insulating from the pipe 11 and then, the electrodes 14 is connected to a terminal board by a lead wire. A pair of reinforcing plates 16 formed the section in a circular arc by a magnetic material is inserted and is buried in the lining 12 crossing at right angles to the direction of the magnetic flux 15 at the time of forming the lining 12.

Description

【発明の詳細な説明】 本発明は測定管内を流れる流体の流量を電気的に測定す
る電磁流量計に関するものである〇一般に電磁流量計は
７アラデーの電磁誘導現象を利用して測定管内を流れる
導電性流体の流量を電気信号に変換して測定を行なうも
のであって、従来第１図に縦断面図とそのＡＡ断面図と
で示すように栴成されてい几０すなわち、絶縁２イニン
グ１で内張シされ几測定管２は、被測定流体が流れる本
管の途中に７ランジ接合されており、この測定管２の外
周面には鞍形に形成された一対の励磁コイル３がコアと
取付は台を介し対向して取付けら葺ている。ま次、測定
管２の軸線方向中央部外周面には、一対の電極４が、測
定管２内の流水方向と、励磁コイル３で形成さ１−た磁
束方向との両方向に直交する位置に対向して挿入されて
いる。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic flowmeter that electrically measures the flow rate of fluid flowing in a measurement pipe. In general, an electromagnetic flowmeter utilizes the phenomenon of electromagnetic induction of 7Aradis to measure the flow rate of fluid flowing in a measurement pipe. This device converts the flow rate of a conductive fluid into an electrical signal for measurement, and has conventionally been constructed as shown in the vertical cross-sectional view and its AA cross-sectional view in Figure 1. The measuring tube 2 is lined with 7 langes and is joined to the main tube through which the fluid to be measured flows, and a pair of saddle-shaped excitation coils 3 are attached to the outer circumferential surface of the measuring tube 2. The roofs are installed facing each other through a stand. Next, a pair of electrodes 4 are placed on the outer circumferential surface of the central portion of the measuring tube 2 in the axial direction, at positions perpendicular to both the direction of water flow in the measuring tube 2 and the direction of the magnetic flux formed by the excitation coil 3. They are inserted facing each other.

こうすることにニジ、励磁コイル３′ｆｔ励磁させると
、測定管２内の流水を横切ってその流水方向と直交する
磁界が形成され、ファラデーの法則により平均流速に比
例する起電力が両電極４間に発生するので、こｆｌ、１
ｒ、増幅器で増幅して発信させることによって流体の流
量を測定し几シ流量の定値制御を行なったりすることが
できる。In this case, when the excitation coil 3' is excited, a magnetic field is formed across the flowing water in the measuring tube 2 and perpendicular to the direction of the flowing water, and according to Faraday's law, an electromotive force proportional to the average flow velocity is applied to both electrodes 4. Since this occurs between fl, 1
By amplifying the signal with an amplifier and transmitting it, the flow rate of the fluid can be measured and the constant value control of the flow rate can be performed.

このように楢成された電磁流量針においては、被測定流
体が高温の場合や、操業中断時等に測定管２内が低圧に
なった場合などに測定管２の絶縁２イニング１が変形し
て接着部が剥離することがあ夛、この剥離が生じると測
定誤差が発生して極端な場合には測定不能になる。そこ
で従来、図に示すように多孔を穿設したステンレス製の
補強管５を絶縁ライニング１中に埋設することが実施さ
れている。In the electromagnetic flow needle constructed in this way, the insulation 2 of the measuring tube 2 may deform when the fluid to be measured is at a high temperature or when the pressure inside the measuring tube 2 becomes low due to interruptions in operation, etc. The adhesive may often peel off, and when this peeling occurs, measurement errors occur, and in extreme cases, measurement becomes impossible. Therefore, as shown in the figure, a stainless steel reinforcing tube 5 with perforated holes has conventionally been buried in the insulating lining 1.

しかしながら、このような従来の補強管５は、非磁性材
で絶縁ライニング１の全周にわたって形成されて姑る次
めに、第２図に示すように励磁コイル３によって形成さ
れる磁束６が拡散されて電極４の位置へ集束されないの
で、必ずしも満足し几磁束の有効利用を期待することが
できながった。However, such a conventional reinforcing tube 5 is formed of a non-magnetic material over the entire circumference of the insulating lining 1, and secondly, as shown in FIG. 2, the magnetic flux 6 formed by the excitation coil 3 is diffused. Since the magnetic flux is not focused at the position of the electrode 4, it is not always possible to expect satisfactory use of the magnetic flux.

本発明は以上のような点に鑑みなされたもので、測定管
に内張りさｊ、る絶縁ライニングに埋設される補強体を
磁性材料を用いて断面円弧状に形成し磁束と直交するＬ
うに対向させて設けることにより、磁束を電極位置へ集
束させて励磁電流とコイル巻数の減少によるコストの低
減を計った電磁流量計を提供するものである。以下、本
発明の実施例を図面に基いて詳細に説明する。The present invention has been made in view of the above points, and a reinforcing body embedded in the insulating lining of the measuring tube is formed using a magnetic material to have an arcuate cross section, and L is perpendicular to the magnetic flux.
The present invention provides an electromagnetic flowmeter in which the magnetic flux is focused on the electrode position by arranging the electrodes facing each other, thereby reducing the cost by reducing the excitation current and the number of turns of the coil. Embodiments of the present invention will be described in detail below with reference to the drawings.

第３図ないし第５図は本発明に係る電磁流量計の実施例
を示し、第３図はその要部の斜視図、第４図は同じぐ断
面図、第５図は磁束の状態を第２図に対応して示す断面
図である０図において、被測定流体が流ｊ、る本管の途
中には測定管１１が７２ンジ接合されており、その内面
にはテフロン等の合成樹脂で成形さ第１．た絶縁ライニ
ング１２が内張すされている０測定管１１の外周面には
、鞍形枠状に巻線さｎ、た一対の励磁コイル１３がこノ
１．を内包する図示しないコアと取付台を介し互に対向
して取付けらｎ、ているｏｆ２測定’［１１の軸線方向
中央部には、一対の電極１４が、測定管１１内の流水方
向と、励磁コイル１３で形成される磁束１５の方向との
両方向に直交する位置に対向して測定管１１と絶縁状態
で挿入されており、図示しない端子盤との間をリード線
で接続されている０そして、前記絶縁ライニング１２に
は、磁性材料で断面円弧状に形成された一対の補強板１
６が、磁束１５の方向と直交し、絶縁２イニング１２の
成形時にインサートされることによって埋設されている
。3 to 5 show an embodiment of the electromagnetic flowmeter according to the present invention, FIG. 3 is a perspective view of the main parts, FIG. 4 is a sectional view of the same, and FIG. 5 shows the state of magnetic flux. In Figure 0, which is a cross-sectional view corresponding to Figure 2, a measuring tube 11 is connected at 72 points in the middle of the main pipe through which the fluid to be measured flows, and its inner surface is made of synthetic resin such as Teflon. Molded 1st. On the outer peripheral surface of the measuring tube 11, which is lined with an insulating lining 12, a pair of excitation coils 13 are wound in a saddle-shaped frame shape. A pair of electrodes 14 are installed at the center in the axial direction of the measurement tube 11 to face each other via a core (not shown) containing a core and a mounting base. It is inserted in an insulated state from the measurement tube 11 at a position perpendicular to the direction of the magnetic flux 15 formed by the excitation coil 13, and is connected to a terminal board (not shown) by a lead wire. The insulating lining 12 includes a pair of reinforcing plates 1 made of a magnetic material and having an arcuate cross section.
6 is orthogonal to the direction of the magnetic flux 15 and is embedded by being inserted during molding of the insulation lining 12.

以上のように構成さｆ’Ｌｆｃ電磁流量計を本管の途中
にフランジ接合し、励磁コイル１３を励磁させると、測
定管１１内を流れる流体を横切ってその流ｎ、力方向直
交する磁束１５を有する磁界が形成さｎ、る。したがっ
て流水方向と磁束°方向との両方にＦｔ交する工うに設
けら７１．た両電極１４間には、ファラデーの法則にエ
リ平均流速に比例した起電力が発生し、こｊがリード線
と端子盤を経て増幅′器へ導かＶ、たのち信号が発せら
れることにエリ流量が測定されたり、流量の定値制御が
行なわれたシする。When the f'Lfc electromagnetic flowmeter constructed as described above is flange-jointed in the middle of the main pipe and the excitation coil 13 is excited, the flow n crosses the fluid flowing in the measurement pipe 11, and the magnetic flux 15 perpendicular to the force direction is generated. A magnetic field is formed having n, ru. Therefore, 71. According to Faraday's law, an electromotive force proportional to the average flow velocity is generated between the two electrodes 14, and this is led to the amplifier via the lead wire and terminal board. The flow rate is measured or constant value control of the flow rate is performed.

このような流量測定においては、第３図を第２図と比較
すれば明らかなように、磁性材料を用いた一対の補強板
１６を磁束１５の方向と直交させ互に対向させて絶縁ラ
イニング１２中に埋設したことによｐ１電磁１５がこの
補強板１６で集束され、測定管１１の外部を通過するこ
となくほとんどが測定管１１内を通過するので、電極１
４０周辺を通る磁束１５は、第２図に示す場合工９も強
くなる。In such a flow rate measurement, as is clear from a comparison of FIG. 3 with FIG. By embedding the P1 electromagnetic material 15 in the reinforcing plate 16, most of it passes through the measuring tube 11 without passing through the outside of the measuring tube 11.
The magnetic flux 15 passing around 40 also becomes stronger in case 9 shown in FIG.

以上の説明にエリ明らかな工うに、本発明に工れば電磁
流量計において、測定管に内張シされる絶縁ライニング
中に、磁性材料を用いて断面円弧状に形成し九一対の補
強板を、磁束と直交するように互に対向させて埋設する
ことにより、この補強板′ｆｒ通過して環状に形成さｊ
、る磁束が、主として測定管内を通過するようｒ集束さ
れて磁束を有効に利用することができ、電極周辺に集中
して起電力が強くなるので、同じ起電力を得る場合従来
と比較して励磁ａイルの巻数を少なくしたり励磁電流を
弱’ＣＬ＞’ｃ：すすることができ、製造コストを低減
させることができるとともに、絶縁ライニングが補強さ
れてその測定管からの剥離を防止することができる。As is clear from the above explanation, the present invention provides an electromagnetic flowmeter in which the insulating lining lined in the measuring tube is formed with a magnetic material and has an arcuate cross section, and 91 pairs of reinforcements are applied. By burying the plates facing each other perpendicularly to the magnetic flux, the reinforcing plate 'fr passes through and is formed into an annular shape.
, the magnetic flux mainly passes through the measurement tube and can be used effectively, and the electromotive force becomes stronger as it concentrates around the electrodes, so compared to conventional methods when obtaining the same electromotive force. The number of turns of the excitation coil can be reduced or the excitation current can be reduced to a low level, reducing manufacturing costs and reinforcing the insulating lining to prevent it from peeling off from the measuring tube. be able to.

【図面の簡単な説明】[Brief explanation of drawings]

第１図および第２図は従来の電磁流量計を示し、第１図
（、）はその縦断面図、第１図（ｂ）は第１図（＆）の
ＡＡ断面図、第２図は磁束の状態を説明するための断面
図、第３図ないし第５図は本発明に係る電磁流量計の実
施例を示し、第３図はその要部の斜視図、第４図は同じ
く断面図、第５図は磁束の状態を第２図に対応して示す
断面図である。 １１・・・・測定管、１２・・・・絶縁ライニング、１
５・・・・磁束、１６・・・・補強板。 特許出願人　山武ハネウェル株式会社 代理人山川政樹（ほか１名） 第１頁の続き ＠発　明　者　黒田正人 東京都大田区西六郷４丁目２８番 １号山武ハネウェル株式会社蒲 田土場内 （７）発　明　者　松本良一部− 東京都太田区西六郷４丁目２８番 １号山武ハネウェル株式会社蒲 田工場内Figures 1 and 2 show a conventional electromagnetic flowmeter. Figure 1 (,) is a longitudinal sectional view, Figure 1 (b) is an AA sectional view of Figure 1 (&), and Figure 2 is A sectional view for explaining the state of magnetic flux, FIGS. 3 to 5 show an embodiment of an electromagnetic flowmeter according to the present invention, FIG. 3 is a perspective view of the main part thereof, and FIG. 4 is a sectional view as well. , FIG. 5 is a sectional view corresponding to FIG. 2, showing the state of magnetic flux. 11...Measuring tube, 12...Insulating lining, 1
5... Magnetic flux, 16... Reinforcement plate. Patent Applicant Yamatake Honeywell Co., Ltd. Agent Masaki Yamakawa (and 1 other person) Continued from page 1 @ Inventor Masato Kuroda From Yamatake Honeywell Co., Ltd. Kamata Doba (7), 4-28-1 Nishirokugo, Ota-ku, Tokyo Mr. Ryoichi Matsumoto - Yamatake Honeywell Co., Ltd. Kamata Factory, 4-28-1 Nishirokugo, Ota-ku, Tokyo

Claims (1)

【特許請求の範囲】[Claims] 測定管に内張シされる絶縁ライニング中に磁性材を用い
て断面円弧状に形成し次一対の補強板を、磁束と直交し
互に対向させて埋設したことを特徴とする電磁流量計。An electromagnetic flowmeter characterized in that a pair of reinforcing plates made of a magnetic material and having an arcuate cross section are embedded in an insulating lining lined within a measuring tube so as to be perpendicular to the magnetic flux and facing each other.