JP2003215013A - Electromagnetic specific gravity meter - Google Patents
Electromagnetic specific gravity meterInfo
- Publication number
- JP2003215013A JP2003215013A JP2002016425A JP2002016425A JP2003215013A JP 2003215013 A JP2003215013 A JP 2003215013A JP 2002016425 A JP2002016425 A JP 2002016425A JP 2002016425 A JP2002016425 A JP 2002016425A JP 2003215013 A JP2003215013 A JP 2003215013A
- Authority
- JP
- Japan
- Prior art keywords
- stator
- mover
- specific gravity
- electromagnetic
- solution
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D3/00—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups
- G01D3/06—Indicating or recording apparatus with provision for the special purposes referred to in the subgroups with provision for operation by a null method
- G01D3/066—Balancing a force which represents the measuring value, by means of a reference force
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
- G01N9/10—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by observing bodies wholly or partially immersed in fluid materials
- G01N9/12—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by observing bodies wholly or partially immersed in fluid materials by observing the depth of immersion of the bodies, e.g. hydrometers
- G01N9/18—Special adaptations for indicating, recording, or control
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Level Indicators Using A Float (AREA)
Abstract
Description
【０００１】[0001]
【発明が属する技術分野】本発明は、各種溶液の比重値
測定に供する、電磁式比重計に関するものである。TECHNICAL FIELD The present invention relates to an electromagnetic hydrometer used for measuring the specific gravity of various solutions.
【０００２】[0002]
【従来の技術】図１は、従来のフロート式比重計の構成
図である。１はフロート、２は糸、３は比重計、４は被
測定溶液である。フロート１には自身の重力Ｗと、その
体積Ｖと被測定溶液４の比重値μの積に応じた、浮力μ
Ｖが作用し、その差が糸２に張力Ｔとして伝わってい
る。比重計３は張力Ｔを電気信号に変換するもので、精
密バネの利用によって張力Ｔを変位量に変換し、その変
位量を電気的に検出するもの、あるいは歪ゲージなどの
利用によって張力Ｔを電気信号に変換し、溶液の比重値
に換算する製品など、多数が実用化されている。2. Description of the Related Art FIG. 1 is a block diagram of a conventional float type hydrometer. 1 is a float, 2 is a thread, 3 is a hydrometer, and 4 is a solution to be measured. The float 1 has a buoyancy μ according to the product of its own gravity W, its volume V and the specific gravity value μ of the measured solution 4.
V acts, and the difference is transmitted to the yarn 2 as the tension T. The densitometer 3 converts the tension T into an electric signal, converts the tension T into a displacement amount by using a precision spring, and electrically detects the displacement amount, or uses the strain gauge to measure the tension T. Many have been put into practical use, such as products that are converted into electrical signals and converted into specific gravity values of solutions.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、フロー
ト式比重計は構造上、流速の速い場所には設置できない
ため、本来の送液配管ないしは建浴槽、反応槽などから
バイパス配管したサンプリング槽を設けて、その上に設
置する必要があった。図１において、５はサンプリング
槽、６はサンプリング槽内の有孔カバーであり、フロー
トに対する流速の影響を最小限に抑えている。しかしな
がら流速を抑えているために、液質の変化に対して、検
出の時間遅れが発生したり、フロート１に気泡が付着し
て測定誤差の原因にもなった。また被測定溶液４が有毒
ガスや腐食性ガスを発生する用途には不向きであり、た
とえ使用しても比重計３は短寿命であった。さらに高圧
配管上に設置する用途に至っては、対象外であった。However, since the float type hydrometer cannot be installed in a place where the flow velocity is high due to its structure, it is necessary to provide a sampling tank which is an original liquid feeding pipe or a construction bath, a bypass pipe from a reaction tank, etc. , Had to be installed on it. In FIG. 1, 5 is a sampling tank, and 6 is a perforated cover in the sampling tank, which minimizes the influence of the flow velocity on the float. However, since the flow velocity is suppressed, a detection time delay occurs with respect to a change in liquid quality, and air bubbles adhere to the float 1, which also causes a measurement error. Further, the solution 4 to be measured is not suitable for use in generating toxic gas or corrosive gas, and even if used, the hydrometer 3 had a short life. Furthermore, it was out of scope when it was installed on high-pressure piping.
【０００４】[0004]
【課題を解決するための手段】本発明の電磁式比重計
は、可動子（フロート）と固定子が磁気的に結合した構
造であり、固定子側のコイルに通電することで、可動子
（フロート）に電磁力が発生する。従来のフロート式比
重計の糸による張力Ｔの伝達に替わって、可動子に作用
する重力Ｗと浮力μＶの差、に相当する電磁力Ｆを、固
定子側の巻線（コイル）に通電する電流値として検出す
る。可動子の鉛直方向位置をホール素子などを利用して
検出し、被測定溶液の比重値が変動しても、可動子が常
に同じ位置を保つように自動制御する。The electromagnetic pycnometer of the present invention has a structure in which a mover (float) and a stator are magnetically coupled to each other. Electromagnetic force is generated in the float. Instead of transmitting the tension T by the thread of the conventional float type hydrometer, an electromagnetic force F corresponding to the difference between the gravity W acting on the mover and the buoyancy μV is applied to the winding (coil) on the stator side. It is detected as a current value. The vertical position of the mover is detected using a Hall element or the like, and automatic control is performed so that the mover always maintains the same position even if the specific gravity of the solution to be measured changes.
【０００５】[0005]
【発明の実施の形態】図２は、本発明の電磁式比重計の
１実施例である。７は可動子（フロート）で、鉛直方向
にドーナツ状の貫通孔を持ち、該貫通孔の周面にマグネ
ット磁気回路を内蔵している。８は固定子で、可動子と
の相対部には、磁気回路、巻線（コイル）と、ホール素
子などによる可動子の位置検出手段を内蔵している。４
は被測定溶液、５はサンプリング槽である。９は電磁式
の導電率計、１０は液温度センサであり、１本のセンサ
で溶液の複数の特性を計測することも可能である。可動
子（フロート）に作用する浮力の検出には糸を使用して
いないので、流速の速い配管上やタンク内にも直接設置
できる。また外気との密閉が容易なので、有毒ガスや腐
食性ガスが発生する用途はもちろん、高圧配管上にも設
置可能である。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows an embodiment of an electromagnetic hydrometer of the present invention. A mover (float) 7 has a doughnut-shaped through hole in the vertical direction, and a magnet magnetic circuit is built in the peripheral surface of the through hole. Reference numeral 8 denotes a stator, which has a magnetic circuit, a winding (coil), and a position detecting means for the mover, such as a Hall element, built-in in a portion facing the mover. Four
Is a solution to be measured, and 5 is a sampling tank. Reference numeral 9 is an electromagnetic conductivity meter, and 10 is a liquid temperature sensor, and it is possible to measure a plurality of characteristics of the solution with one sensor. Since no thread is used to detect the buoyancy acting on the mover (float), it can be installed directly on a pipe with a high flow velocity or in a tank. In addition, since it can be easily sealed from the outside air, it can be installed on high-pressure pipes as well as applications that generate toxic or corrosive gases.
【０００６】[0006]
【実施例】図３は、本発明の電磁式比重計の１実施例
で、可動子７と固定子８の内部構造図である。２１は可
動子のマグネット、２２は可動子のヨーク（磁路鉄
部）、１１は固定子のマグネット、１２は固定子のヨー
ク（磁路鉄部）、１３は固定子の巻線（コイル）、１４
はホール素子で、Ｎ極側、Ｓ極側それぞれ３個づつ、計
６個を配置している。１５はＯリング、１６は固定子の
ケース、１７はシャフト、１８はスペーサ、１９は下部
ホルダー、２０は上部ホルダー、２３は可動子ケース
で、いずれも非磁性材で構成される。２４は鉄製リング
で、周囲への漏れ磁束防止用である。図３の固定子の断
面図のうち、中心線より上図は、円柱状のヨーク１２の
表面に巻線（コイル）１３を設置した実施例であり、固
定子の中心線より下図は、ヨーク１２にスロットを設
け、スロット内に巻線（コイル）１３を設置した実施例
である。可動子マグネット２１と固定子マグネット１１
は同極性で、反発し合うように配置してあるため、可動
子７と固定子８が接触しても摩擦力は発生しない。一
方、固定子コイル１３に通電する電流は、可動子マグネ
ット２１による磁束密度との積によって電磁力Fを発生
する。可動子７が、その鉛直方向位置を保つように、コ
イル電流をコントロールすることで、可動子７に作用す
る浮力μＶを、ひいては被測定溶液の比重値を、コイル
電流として検出する。図３の可動子の断面図のうち、中
心線より左図は、可動子ヨーク１２がマグネット接合部
付近において面取りされており、可動子マグネット２１
を固定子から若干離した構造を持った実施例である。こ
の実施例では、中央点付近における可動子位置の整定性
が改善される。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is an internal structure diagram of a mover 7 and a stator 8 in one embodiment of the electromagnetic gravimeter of the present invention. Reference numeral 21 is a magnet of the mover, 22 is a yoke of the mover (iron part of the magnetic path), 11 is a magnet of the stator, 12 is a yoke of the stator (iron part of the magnetic path), and 13 is a winding (coil) of the stator. , 14
Is a Hall element, and three N-sides and three S-sides are arranged, for a total of six. Reference numeral 15 is an O-ring, 16 is a case of a stator, 17 is a shaft, 18 is a spacer, 19 is a lower holder, 20 is an upper holder, and 23 is a mover case, all of which are made of a non-magnetic material. Reference numeral 24 is an iron ring for preventing leakage of magnetic flux to the surroundings. In the cross-sectional view of the stator of FIG. 3, the drawing above the center line is an embodiment in which the winding (coil) 13 is installed on the surface of the cylindrical yoke 12, and the drawing below the center line of the stator is the yoke. This is an example in which a slot is provided in 12 and a winding (coil) 13 is installed in the slot. Mover magnet 21 and stator magnet 11
Since they have the same polarity and are arranged so as to repel each other, no frictional force is generated even if the mover 7 and the stator 8 come into contact with each other. On the other hand, the current passing through the stator coil 13 produces an electromagnetic force F due to the product of the magnetic flux density of the mover magnet 21 and the magnetic flux density. By controlling the coil current so that the mover 7 maintains its vertical position, the buoyancy μV acting on the mover 7, and thus the specific gravity of the solution to be measured, is detected as the coil current. In the sectional view of the mover shown in FIG. 3, the left side from the center line shows that the mover yoke 12 is chamfered in the vicinity of the magnet joint, and the mover magnet 21
This is an embodiment having a structure in which is slightly separated from the stator. In this embodiment, the settling property of the mover position near the center point is improved.
【０００７】図４は、本発明の電磁式比重計で使用する
電気回路の１実施例である。１４はホール素子、３１は
差動増幅器、３２は加算器、１３は固定子コイル、３３
はコイル電流の検出抵抗、３４は増幅器である。６個の
ホール素子電圧を加算した上、固定子のコイル電流によ
るホール素子電圧の低下分を加え、さらにオフセット電
圧Ｖｏｆｆの調整をして、可動子７の鉛直方向（Ｚ方
向）位置に比例した電圧Ｖｚを得る。３５はＶｚの微分
回路で、可動子の速度信号を得る。３６は可動子の位置
信号Ｖｚを一定にコントロールするＰＩＤ増幅器、３７
は可動子の速度をコントロールするＰＩＤ増幅器、３８
は固定子のコイル電流をコントロールするＰＩＤ増幅
器、３９は固定子コイル１３への電流供給回路であり、
合わせて３重の負帰還閉ループを構成している。例え
ば、３６の出力は速度指令値であり、実際速度（ｄＶｚ
／ｄt）との差を３７への入力とする。同様に、３７の
出力はコイル電流指令値であり、実際電流値との差を３
８への入力としている。以上の構成により、可動子７の
鉛直方向位置を常に一定に保つように、電流が固定子コ
イル１３に供給される。そのコイル電流値を計測するこ
とで、可動子と固定子間に作用する電磁力Ｆを、ひいて
は被測定溶液の比重値を計測する。FIG. 4 shows an embodiment of an electric circuit used in the electromagnetic hydrometer of the present invention. 14 is a hall element, 31 is a differential amplifier, 32 is an adder, 13 is a stator coil, 33
Is a resistor for detecting the coil current, and 34 is an amplifier. In addition to adding the six Hall element voltages, the decrease in Hall element voltage due to the coil current of the stator was added, and the offset voltage Voff was further adjusted to be proportional to the vertical (Z direction) position of the mover 7. Obtain the voltage Vz. A Vz differentiating circuit 35 obtains a velocity signal of the mover. Reference numeral 36 is a PID amplifier for controlling the position signal Vz of the mover to be constant, 37
Is a PID amplifier that controls the speed of the mover, 38
Is a PID amplifier for controlling the coil current of the stator, 39 is a current supply circuit for the stator coil 13,
Together, they form a triple negative feedback closed loop. For example, the output of 36 is the speed command value, and the actual speed (dVz
The difference from / dt) is input to 37. Similarly, the output of 37 is the coil current command value, and the difference from the actual current value is 3
Input to 8. With the above configuration, the current is supplied to the stator coil 13 so that the vertical position of the mover 7 is always kept constant. By measuring the coil current value, the electromagnetic force F acting between the mover and the stator, and by extension, the specific gravity value of the solution to be measured is measured.
【０００８】図５は、本発明による電磁式比重計の別の
１実施例である。可動子７を内側にすることで、固定子
８はサンプリング槽５の外側に設置した。４は被測定溶
液で、１１〜２２は図３と同じである。ドーナツ状のフ
ロートである可動子７は、その外周にマグネット磁気回
路（２１、２２）を備え、円筒状の固定子８のマグネッ
ト磁気回路（１１、１２）と相対している。固定子８は
コイル１３とホール素子１４を備え、動作原理は図３と
同じで、電気回路も図４と同じである。FIG. 5 shows another embodiment of the electromagnetic hydrometer according to the present invention. The stator 8 was installed outside the sampling tank 5 by setting the mover 7 inside. 4 is a solution to be measured, and 11 to 22 are the same as those in FIG. The mover 7, which is a doughnut-shaped float, is provided with magnet magnetic circuits (21, 22) on its outer circumference and faces the magnet magnetic circuits (11, 12) of the cylindrical stator 8. The stator 8 includes a coil 13 and a Hall element 14, the operating principle is the same as in FIG. 3, and the electric circuit is also the same as in FIG.
【０００９】図６は、本発明による電磁式比重計の別の
１実施例である。固定子８を上下に分割し、紡錘状のフ
ロートである可動子７のマグネット２１も、上下に配置
した。１１〜２２は図３と同じである。可動子７のマグ
ネット２１は円筒状で、半径方向に着磁されている。す
なわち上側の可動子マグネットは外周がすべてN極、内
周がすべてS極であり、下側の可動子マグネットは外周
がすべてS極、内周がすべてN極に着磁されている。上下
２個の可動子マグネット２１はフロート内部のヨーク２
２を通じて磁気的に結合している。固定子のマグネット
１１は、被測定溶液が流通する配管の外側に、左右２個
配置され、共に上側がN極、下側がS極で、可動子マグネ
ット２１と反発する向きに配置する。長い４本のヨーク
１２は、可動子７の上下マグネットと相対する位置で、
円筒状に形成され、コイル１３とホール素子１４を伴な
って、固定子８を構成している。動作原理は図３と同じ
で、電気回路も図４と同じである。FIG. 6 shows another embodiment of the electromagnetic hydrometer according to the present invention. The stator 8 was divided into upper and lower parts, and the magnets 21 of the mover 7, which was a spindle-shaped float, were also arranged in the upper and lower parts. 11 to 22 are the same as those in FIG. The magnet 21 of the mover 7 has a cylindrical shape and is magnetized in the radial direction. That is, the upper mover magnet has the N pole on the outer circumference and the S pole on the inner circumference, and the lower mover magnet has the S pole on the outer circumference and the N pole on the inner circumference. The upper and lower two mover magnets 21 are the yoke 2 inside the float.
It is magnetically coupled through 2. Two stator magnets 11 are arranged on the outside of the pipe through which the solution to be measured flows, both of which are N poles on the upper side and S poles on the lower side, and are arranged so as to repel the mover magnet 21. The four long yokes 12 are at positions facing the upper and lower magnets of the mover 7,
The stator 8 is formed in a cylindrical shape and is accompanied by the coil 13 and the Hall element 14. The principle of operation is the same as in FIG. 3, and the electric circuit is also the same as in FIG.
【００１０】[0010]
【発明の効果】以上説明したように、本発明の電磁式比
重計は、可動子（フロート）に作用する力の検出に糸を
使用しないので、流速の速い配管上やタンク内にも直接
設置できる。また外気との密閉が容易であり、有毒ガス
や腐食性ガスが発生する用途はもちろん、高圧配管上に
も設置可能である。さらに、図２で説明したように、固
定子側に水素イオン濃度（ＰＨ）計、酸化還元電位（Ｏ
ＲＰ）計、導電率計、液温度センサなどを組み込むこと
により、１本のセンサで溶液の複数の特性を計測するこ
とが可能である。As described above, since the electromagnetic hydrometer of the present invention does not use a thread for detecting the force acting on the mover (float), it can be directly installed on a pipe having a high flow velocity or in a tank. it can. In addition, it can be easily sealed from the outside air and can be installed on high-pressure pipes as well as in applications where toxic gas or corrosive gas is generated. Further, as described in FIG. 2, a hydrogen ion concentration (PH) meter and a redox potential (O
By incorporating an RP) meter, a conductivity meter, a liquid temperature sensor, etc., it is possible to measure a plurality of characteristics of a solution with one sensor.
【図１】従来のフロート式比重計と、サンプリング槽へ
の設置図。FIG. 1 is a diagram showing a conventional float type hydrometer and installation in a sampling tank.
【図２】本発明の電磁式比重計で、電磁式導電率計と液
温度センサを備えた、１実施例。FIG. 2 is an example of an electromagnetic hydrometer of the present invention, which includes an electromagnetic conductivity meter and a liquid temperature sensor.
【図３】本発明の電磁式比重計の１実施例で、可動子と
固定子の構造図。FIG. 3 is a structural diagram of a mover and a stator in one embodiment of the electromagnetic hydrometer of the present invention.
【図４】本発明の電磁式比重計の１実施例で、電気回路
のブロック図。FIG. 4 is a block diagram of an electric circuit in one embodiment of the electromagnetic hydrometer of the present invention.
【図５】本発明の電磁式比重計の別の１実施例で、簡単
な構造図。FIG. 5 is a simple structural diagram of another embodiment of the electromagnetic hydrometer of the present invention.
【図６】本発明の電磁式比重計の別の１実施例で、簡単
な構造図、と配管設置図。FIG. 6 is a simple structural diagram and a piping installation diagram of another embodiment of the electromagnetic hydrometer of the present invention.
１ フロート
２ 糸
３ 従来の比重計
４ 被測定溶液
５ サンプリング槽
６ サンプリング槽内の有孔カバー
７ 電磁式比重計の可動子（フロート）
８ 電磁式比重計の固定子
９ 電磁式の導電率計
１０ 液温度センサ
１１ 固定子マグネット
１２ 固定子ヨーク（磁路鉄部）
１３ 固定子巻線（コイル）
１４ ホール素子
１５ Ｏリング
１６ 固定子ケース
１７ シャフト
１８ スペーサ
１９ 下部ホルダー
２０ 上部ホルダー
２１ 可動子マグネット
２２ 可動子ヨーク（磁路鉄部）
２３ 可動子ケース
２４ 漏れ磁束防止用の鉄製リング
３１ 差動増幅器
３２ 加算器
３３ コイル電流の検出抵抗
３４ 増幅器
３５ 微分回路
３６ 可動子の位置（Ｖｚ）コントロール用ＰＩＤ増幅
器
３７ 可動子の速度（ｄＶｚ／ｄt）コントロール用Ｐ
ＩＤ増幅器
３８ コイル電流のコントロール用ＰＩＤ増幅器
３９ コイル電流供給回路
Ｗ フロート（可動子）に作用する重力
Ｖ フロート（可動子）の体積
μ 被測定溶液の比重値
Ｔ 糸の張力（＝Ｗ−μＶ）
Ｆ フロート（可動子）に作用する鉛直方向の電磁力
（＝Ｗ−μＶ）
Ｖｚ フロート（可動子）の鉛直方向位置信号
ｄＶｚ／ｄt フロート（可動子）の鉛直方向速度信号
Ｖoff フロート（可動子）のオフセット位置調整値1 Float 2 Thread 3 Conventional Density Meter 4 Solution to be Measured 5 Sampling Tank 6 Perforated Cover in Sampling Tank 7 Electromagnetic Densitometer Mover (Float) 8 Electromagnetic Density Stator 9 Electromagnetic Conductivity Meter 10 Liquid Temperature Sensor 11 Stator Magnet 12 Stator Yoke (Magnetic Path Iron Part) 13 Stator Winding (Coil) 14 Hall Element 15 O-Ring 16 Stator Case 17 Shaft 18 Spacer 19 Lower Holder 20 Upper Holder 21 Mover Magnet Reference Signs List 22 mover yoke (iron part of magnetic path) 23 mover case 24 iron ring for leakage flux prevention 31 differential amplifier 32 adder 33 coil current detection resistor 34 amplifier 35 differentiating circuit 36 for mover position (Vz) control PID amplifier 37 P for controlling the speed (dVz / dt) of the mover
ID amplifier 38 PID amplifier 39 for controlling coil current Coil current supply circuit W Gravity acting on float (movable element) V Volume of float (movable element) μ Specific gravity value of solution to be measured T Tension of thread (= W-μV) F Electromagnetic force in the vertical direction acting on the float (movable element) (= W-μV) Vz Vertical position signal of the float (movable element) dVz / dt Vertical velocity signal Voff float (movable element) Offset position adjustment value
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成１４年１月３０日（２００２．１．３
０）[Submission date] January 30, 2002 (2002.1.3
0)
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００６[Correction target item name] 0006
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００６】[0006]
【実施例】図３は、本発明の電磁式比重計の１実施例
で、可動子７と固定子８の内部構造図である。２１は可
動子のマグネット、２２は可動子のヨーク（磁路鉄
部）、１１は固定子のマグネット、１２は固定子のヨー
ク（磁路鉄部）、１３は固定子の巻線（コイル）、１４
はホール素子で、Ｎ極側、Ｓ極側それぞれ３個づつ、計
６個を配置している。１５はＯリング、１６は固定子の
ケース、１７はシャフト、１８はスペーサ、１９は下部
ホルダー、２０は上部ホルダー、２３は可動子ケース
で、いずれも非磁性材で構成される。２４は鉄製リング
で、周囲への漏れ磁束防止用である。図３の固定子の断
面図のうち、中心線より上図は、円柱状のヨーク１２の
表面に巻線（コイル）１３を設置した実施例であり、固
定子の中心線より下図は、ヨーク１２にスロットを設
け、スロット内に巻線（コイル）１３を設置した実施例
である。可動子マグネット２１と固定子マグネット１１
は同極性で、反発し合うように配置してあるため、可動
子７と固定子８が接触しても摩擦力は発生しない。一
方、固定子コイル１３に通電する電流は、可動子マグネ
ット２１による磁束密度との積によって電磁力Fを発生
する。可動子７が、その鉛直方向位置を保つように、コ
イル電流をコントロールすることで、可動子７に作用す
る浮力μＶを、ひいては被測定溶液の比重値を、コイル
電流として検出する。図３の可動子の断面図のうち、中
心線より左図は、可動子ヨーク２２がマグネット接合部
付近において面取りされており、可動子マグネット２１
を固定子から若干離した構造を持った実施例である。こ
の実施例では、中央点付近における可動子位置の整定性
が改善される。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is an internal structure diagram of a mover 7 and a stator 8 in one embodiment of the electromagnetic gravimeter of the present invention. Reference numeral 21 is a magnet of the mover, 22 is a yoke of the mover (iron part of the magnetic path), 11 is a magnet of the stator, 12 is a yoke of the stator (iron part of the magnetic path), and 13 is a winding (coil) of the stator. , 14
Is a Hall element, and three N-sides and three S-sides are arranged, for a total of six. Reference numeral 15 is an O-ring, 16 is a case of a stator, 17 is a shaft, 18 is a spacer, 19 is a lower holder, 20 is an upper holder, and 23 is a mover case, all of which are made of a non-magnetic material. Reference numeral 24 is an iron ring for preventing leakage of magnetic flux to the surroundings. In the cross-sectional view of the stator of FIG. 3, the drawing above the center line is an embodiment in which the winding (coil) 13 is installed on the surface of the cylindrical yoke 12, and the drawing below the center line of the stator is the yoke. This is an example in which a slot is provided in 12 and a winding (coil) 13 is installed in the slot. Mover magnet 21 and stator magnet 11
Since they have the same polarity and are arranged so as to repel each other, no frictional force is generated even if the mover 7 and the stator 8 come into contact with each other. On the other hand, the current passing through the stator coil 13 produces an electromagnetic force F due to the product of the magnetic flux density of the mover magnet 21 and the magnetic flux density. By controlling the coil current so that the mover 7 maintains its vertical position, the buoyancy μV acting on the mover 7, and thus the specific gravity of the solution to be measured, is detected as the coil current. In the sectional view of the mover shown in FIG. 3, the left side from the center line shows that the mover yoke 22 is chamfered in the vicinity of the magnet joint, and the mover magnet 21
This is an embodiment having a structure in which is slightly separated from the stator. In this embodiment, the settling property of the mover position near the center point is improved.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】図面[Document name to be corrected] Drawing
【補正対象項目名】図３[Name of item to be corrected] Figure 3
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【図３】
─────────────────────────────────────────────────────
[Figure 3] ─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成１４年６月１８日（２００２．６．１
８）[Submission date] June 18, 2002 (2002.6.1)
8)
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】特許請求の範囲[Name of item to be amended] Claims
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【特許請求の範囲】[Claims]
Claims (3)
することで、溶液の比重値測定に供する比重計におい
て、 フロートである可動子の内部にマグネット磁気回路を有
し、該可動子と磁気的に相対した固定子の側に磁気回
路、巻線と、ホール素子などによる可動子の鉛直方向位
置の検出手段を有していて、 固定子側の該位置検出手段の信号値が一定となるよう
に、該巻線に通電することで、可動子と固定子の間に電
磁力を発生させ、ひいては可動子に作用する重力、浮力
と電磁力をバランスさせることによって、被測定溶液の
比重値を固定子側の巻線電流値により計測することを特
徴とする、電磁式比重計。1. A hydrometer for measuring the specific gravity of a solution by measuring the buoyancy acting on the float in the solution, wherein a magnet magnetic circuit is provided inside the mover, which is the float, and Has a magnetic circuit, a winding, and a means for detecting the vertical position of the mover by means of a Hall element, etc. on the side of the stator that is opposite to each other, and the signal value of the position detection means on the side of the stator becomes constant. As described above, by energizing the winding, an electromagnetic force is generated between the mover and the stator, which in turn balances the gravity acting on the mover, the buoyancy and the electromagnetic force. An electromagnetic hydrometer, characterized in that the winding current value on the stator side is measured.
のマグネット磁気回路の極性を反発し合う向きに構成す
ることによって、可動子と固定子の間に摩擦力が作用し
ないようにした、請求項１の電磁式比重計。2. The frictional force does not act between the mover and the stator by arranging the magnet magnetic circuit of the mover and the magnet magnetic circuit of the stator so as to repel each other in polarity. Item 1. Electromagnetic hydrometer.
計、酸化還元電位（ＯＲＰ）計、導電率計、液温度セン
サ、など比重値以外の溶液特性を計測するセンサを固定
子側に組み込んだ、請求項１の電磁式比重計。3. The hydrogen ion concentration (PH) of the measured solution
The electromagnetic specific gravity meter according to claim 1, wherein a sensor, such as a meter, an oxidation-reduction potential (ORP) meter, a conductivity meter, a liquid temperature sensor, which measures solution characteristics other than the specific gravity value, is incorporated in the stator side.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002016425A JP3340123B1 (en) | 2002-01-25 | 2002-01-25 | Electromagnetic specific gravity meter |
| PCT/JP2003/000497 WO2003065015A1 (en) | 2002-01-25 | 2003-01-21 | Electromagnetic gravimeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002016425A JP3340123B1 (en) | 2002-01-25 | 2002-01-25 | Electromagnetic specific gravity meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP3340123B1 JP3340123B1 (en) | 2002-11-05 |
| JP2003215013A true JP2003215013A (en) | 2003-07-30 |
Family
ID=19192002
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002016425A Expired - Fee Related JP3340123B1 (en) | 2002-01-25 | 2002-01-25 | Electromagnetic specific gravity meter |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP3340123B1 (en) |
| WO (1) | WO2003065015A1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7308379B2 (en) * | 2005-04-14 | 2007-12-11 | Halliburton Energy Services, Inc. | Methods and systems for estimating density of a material in a mixing process |
| US7353874B2 (en) | 2005-04-14 | 2008-04-08 | Halliburton Energy Services, Inc. | Method for servicing a well bore using a mixing control system |
| US7494263B2 (en) | 2005-04-14 | 2009-02-24 | Halliburton Energy Services, Inc. | Control system design for a mixing system with multiple inputs |
| US8177411B2 (en) | 2009-01-08 | 2012-05-15 | Halliburton Energy Services Inc. | Mixer system controlled based on density inferred from sensed mixing tub weight |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5924375B2 (en) * | 1976-09-30 | 1984-06-08 | 横河電機株式会社 | liquid hydrometer |
| JPS6010149A (en) * | 1983-06-30 | 1985-01-19 | Nec Home Electronics Ltd | Apparatus for measuring specific gravity of liquid |
-
2002
- 2002-01-25 JP JP2002016425A patent/JP3340123B1/en not_active Expired - Fee Related
-
2003
- 2003-01-21 WO PCT/JP2003/000497 patent/WO2003065015A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| WO2003065015A1 (en) | 2003-08-07 |
| JP3340123B1 (en) | 2002-11-05 |
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