JP2006090539A

JP2006090539A - Magnetic bearing

Info

Publication number: JP2006090539A
Application number: JP2004308869A
Authority: JP
Inventors: Takahiko Ito; 孝彦伊東; Junko Seki; 純子関
Original assignee: YUKIGAYA SEIGYO KENKYUSHO KK; Yukigaya Institute Co Ltd
Current assignee: YUKIGAYA SEIGYO KENKYUSHO KK; Yukigaya Institute Co Ltd
Priority date: 2004-09-25
Filing date: 2004-09-25
Publication date: 2006-04-06

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize the operation of a magnetic levitation control loop by improving control characteristic of a magnetic bearing by directly detecting a position change speed by a speed detecting device, and removing influence by noise generated on a speed signal in differentiation, and influence caused by delay in transmitting the signal which can not be avoided in denoising. <P>SOLUTION: The detecting devices 4, 4a for directly detecting the position change speed are mounted on position detecting devices 3, 3a for detecting a levitation position of the magnetic bearing, thus the control of magnetic levitation is stabilized. As the speed information of high S/N ratio can be obtained, the control can be performed by determining acceleration by differentiating the speed, thus the magnetic bearing capable of being used under severe conditions, which is difficult by a conventional one, can be realized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は磁気吸引力によって浮上させる磁気浮上装置の制御に関するものであって磁気軸受と総称する支持装置の制御方法を改良して磁気軸受の性能を向上させる技術に関わる。 The present invention relates to control of a magnetic levitation device that is levitated by a magnetic attractive force, and relates to a technique for improving the performance of a magnetic bearing by improving a control method of a support device generally called a magnetic bearing.

従来から磁気軸受や、磁気吸引力によって浮上させる磁気浮上装置の制御は、支持体と浮上体との間の相対距離を検出する位置検出装置を備え、位置検装置の出力信号を微分して速度信号を得た上で位置検出装置の出力信号と、速度信号を帰還増幅器に入力して軸受装置である電磁石の磁化力を調節して磁気浮上力を安定に浮上させるべく制御する負帰還ループで構成されている。 Conventionally, the control of a magnetic bearing or a magnetic levitation device that is levitated by a magnetic attraction force has been provided with a position detection device that detects the relative distance between the support and the levitation body, and the output signal of the position detection device is differentiated to speed. In the negative feedback loop that controls the magnetic levitation force stably by obtaining the signal and adjusting the magnetizing force of the electromagnet that is the bearing device by inputting the output signal of the position detection device and the speed signal to the feedback amplifier. It is configured.

位置検出装置の出力信号を微分する際に高域ノイズが含まれ易く，ローパスフィルターを用いている。また、処理速度の高いコンピューターを使用して数値計算を行っても、高域ノイズを除去しようとすると時間遅れが避けられず、制御ループが不安定になり易いので位置検出装置の出力を微分して変化速度計測に替えて予測制御なども用いられている。 When differentiating the output signal of the position detection device, high-frequency noise is likely to be included, and a low-pass filter is used. In addition, even if numerical calculation is performed using a computer with high processing speed, a time delay is unavoidable when trying to remove high-frequency noise, and the control loop tends to become unstable, so the output of the position detection device is differentiated. Therefore, predictive control is also used instead of change rate measurement.

従来技術による距離検装置の出力の微分操作は、原理的には正しい手段であるが、磁気軸受や磁気吸引力によって浮上させる磁気浮上式搬送装置などに適用する場合で、特に高速回転する磁気軸受に適用する場合には、回転体の加工精度誤差や、表面粗さや回転に伴う遠心力による回転体の弾性歪による変位や振動、更に軸受制御に伴う漏洩磁束変動などの影響が位置検装置の出力信号に混入しやすく、距離検出器の出力を微分する際にそれらがノイズとして出力されて、磁気軸受などを良好に制御することを妨げている。 The differential operation of the output of the distance measuring device according to the prior art is a correct means in principle, but when applied to a magnetic bearing or a magnetic levitation transport device that is levitated by a magnetic attractive force, especially a magnetic bearing that rotates at high speed. When applied to the position detection device, the positioning accuracy is affected by the processing accuracy error of the rotating body, the displacement and vibration due to the elastic distortion of the rotating body due to the surface roughness and the centrifugal force accompanying the rotation, and the fluctuation of the leakage magnetic flux accompanying the bearing control. They are easily mixed into the output signal, and when the output of the distance detector is differentiated, they are output as noise, preventing good control of the magnetic bearing and the like.

また、微分操作は原理的に高域利得が大きくなるので、正確な微分出力信号波形を得ることが困難であり、軸の回転角度に同期して相対位置検出器の出力に修正を加えるなどの対策が採られていたが、抜本的な解決には至らず、ＤＳＰなどを用いた対症療法的な手段によって磁気浮上を実現していた。 In addition, since the high frequency gain is increased in principle in the differential operation, it is difficult to obtain an accurate differential output signal waveform, and the output of the relative position detector is corrected in synchronization with the rotation angle of the shaft. Countermeasures have been taken, but no radical solution has been achieved, and magnetic levitation has been realized by means of symptomatic treatment using DSP or the like.

また、アナログ演算による直接微分、デジタルプロセッサーによる数値微分はともに原理的にハイパスフィルターであるので、位置検出装置の出力からローパスフィルターで除去した位置検出装置の出力を微分すると、微分操作によってノイズが再生されて正常な制御を損なうなど、磁気軸受を構成する上での問題があった。 In addition, both direct differentiation by analog computation and numerical differentiation by digital processor are high-pass filters in principle, so if you differentiate the output of the position detector removed by the low-pass filter from the output of the position detector, noise will be reproduced by the differentiation operation As a result, there are problems in configuring the magnetic bearing, such as impairing normal control.

本発明はノイズによる障害の問題を解決しようとしてなされたもので、磁気吸引力で浮上している回転軸の状態を検知する検出装置が受けるノイズのレベルを下げるとともに、より正確な情報を得るために、磁気軸受電磁石の漏洩磁束のレベルが低く、且つ、磁気軸受の作動力の力学的な中心近傍に位置検出装置、または速度検出装置、または位置検出装置と速度検出装置の両方を配置することが課題となっている。 The present invention has been made in order to solve the problem of disturbance caused by noise. In order to reduce the level of noise received by a detection device that detects the state of a rotating shaft that is levitated by magnetic attraction, and to obtain more accurate information. In addition, the position of the position detecting device, the speed detecting device, or both the position detecting device and the speed detecting device is arranged near the dynamic center of the operating force of the magnetic bearing, and the leakage magnetic flux level of the magnetic bearing electromagnet is low. Has become an issue.

磁気力により浮揚支持されている対象物の軸受側からの距離の変化速度を検出する相対速度検出装置と、該相対速度検出装置の出力信号を磁気軸受の磁束を制御する回路の速度信号として磁気軸受の磁化力を制御する装置を備える磁気軸受においては原理的に相対速度を検出する速度検出装置を設けることによって相対速度信号を直接的に出力して，微分操作を経ないで軸受制御を行い安定な磁気軸受制御を実現した． A relative speed detection device that detects the speed of change of the distance from the bearing side of an object that is levitated and supported by a magnetic force, and uses the output signal of the relative speed detection device as a speed signal of a circuit that controls the magnetic flux of the magnetic bearing. In a magnetic bearing equipped with a device for controlling the magnetizing force of the bearing, in principle, a relative speed signal is directly output by providing a speed detection device that detects the relative speed, and the bearing control is performed without performing a differential operation. Stable magnetic bearing control was realized.

微分操作による高域ノイズが再生される問題を解決すべく、相対速度を理学上の原理に基づいて検出する速度検出器を設けることによって、相対速度信号を直接的に出力して磁気軸受の制御を行い、磁気軸受などの制御型磁気浮上装置の安定な制御を実現するように構成した。 In order to solve the problem that high frequency noise due to differential operation is reproduced, a relative speed signal is directly output to control the magnetic bearing by providing a speed detector that detects the relative speed based on the theoretical principle. To achieve stable control of a control type magnetic levitation device such as a magnetic bearing.

請求項１に記載の速度検装置が浮揚支持されている前記回転軸または前記回転軸に取り付けられた導電性部分と、導電性部分に対向して軸受側に設けた電極によって形成された蓄電器と、蓄電器に直流電圧を印加する回路と蓄電器の電極間距離の変化速度に従って蓄電電器の電極に出入する電流または蓄電器の電極間の電圧を検出する回路を備えることを特徴とする請求項１に記載の磁気軸受において、相対速度検出装置として公知の静電容量の変化を利用する方法があるが、工学上の原理的な速度電気変換手段であって構造が簡単であるとともに出力の忠実度が高く原理的にＳ／Ｎ比が高いという特徴を備える． The accumulator formed by the rotating shaft on which the speed detecting device according to claim 1 is levitated or a conductive portion attached to the rotating shaft, and an electrode provided on the bearing side facing the conductive portion, 2. The circuit according to claim 1, further comprising: a circuit that applies a DC voltage to the capacitor and a circuit that detects a current flowing in and out of the electrode of the capacitor or a voltage between the electrodes of the capacitor according to a change speed of a distance between the electrodes of the capacitor. As a relative speed detection device, there is a known method using a change in electrostatic capacity. However, this is a theoretical electrical speed conversion means with a simple structure and high output fidelity. In principle, it has the feature of high S / N ratio.

公知の速度検出装置の一例としては、静電容量を利用する方法では静電マイクロフォンが広く知られており、検出装置としての性能の高さと、Ｓ／Ｎ比の高さはすでに実証されている。 As an example of a known speed detection device, an electrostatic microphone is widely known as a method using capacitance, and the high performance as a detection device and the high S / N ratio have already been demonstrated. .

請求項１に記載の速度検装置が浮揚支持されている前記回転軸、または回転軸に取り付けられた磁性体と、磁性体と電磁的に結合する状態で軸受側に設けたサーチコイルと、サーチコイルにバイアス磁界を与える手段と、サーチコイルと前記回転体の距離の変化速度に従ってサーチコイルに誘導された電流または電圧を検出する回路を備えることを特徴とする請求項１に記載の磁気軸受けにおいて、相対速度検出装置として公知の電磁誘導を利用する方法が知られているが、何れも工学上で原理的な速度電気変換手段であって構造が簡単であるとともに速度に対応する出力の忠実度が高く原理的にＳ／Ｎ比が高いという特徴を備える。 The rotating shaft on which the speed detecting device according to claim 1 is levitated, or a magnetic body attached to the rotating shaft, a search coil provided on the bearing side in an electromagnetically coupled state with the magnetic body, and a search 2. The magnetic bearing according to claim 1, further comprising means for applying a bias magnetic field to the coil, and a circuit for detecting a current or a voltage induced in the search coil in accordance with a changing speed of a distance between the search coil and the rotating body. Although known methods using electromagnetic induction are known as relative speed detection devices, all are speed electrical conversion means that are fundamental in engineering, have a simple structure, and output fidelity corresponding to speed. It is characterized by a high S / N ratio in principle.

公知の速度検出装置の一例としては、電磁誘導を利用する方法は電話等に広く利用されていた受話器と送話器が広く知られており、感度と忠実度が高いので長期に亘って独占的に電話に利用されていた。この技術を磁気軸受の速度検出装置に利用している。 As an example of a known speed detection device, the method using electromagnetic induction is widely known for handsets and transmitters widely used for telephones, etc., and has high sensitivity and fidelity, so it is exclusive for a long time. It was used for telephone. This technology is used in a magnetic bearing speed detection device.

明細書１０乃至１３項に記載の本発明において、検出装置を構成する要素として用いた速度検出手段には既に充分に性能が実証されている公知の手段であるか、または、それらを組み合わせて利用できるので磁気軸受等の浮上制御安定化を実現するためにそれらを利用した。 In the present invention described in the specification 10 to 13, the speed detection means used as an element constituting the detection apparatus is a known means whose performance has already been sufficiently demonstrated, or a combination thereof is used. Because they can be used, they were used to stabilize the levitation control of magnetic bearings.

明細書１０乃至１４項に記載の様に，本発明における速度検出手段には，既に充分に性能が実証されている公知の手段またはそれらを組み合わせるか、新たに発明される速度検出装置、新たに発見される原理を利用した速度検出装置などを利用する事によって，これらの原理及び構造を磁気軸受の浮上体と支持体との間の相対速度検出手段として用いることができる。 As described in the specification 10 to 14, the speed detection means in the present invention is a known means whose performance has already been sufficiently demonstrated, or a combination thereof, or a newly invented speed detection apparatus, newly These principles and structures can be used as a means for detecting the relative speed between the floating body and the support body of the magnetic bearing by using a speed detection device using the discovered principle.

請求項１乃至３に記載の磁気軸受において検出軸毎に複数個の速度検出器を設け、出力回路を差動接続して奇数次歪を減少させる機能を備える速度検出装置を構成して、理学原理による相対速度検出器の位置によって検出感度が変化するという原理的な欠陥を補正して磁気浮上制御に応用することを可能にする。 A magnetic bearing according to any one of claims 1 to 3, wherein a plurality of speed detectors are provided for each detection shaft, and a speed detecting device having a function of reducing odd-order distortion by differentially connecting output circuits is provided. The principle defect that the detection sensitivity changes depending on the position of the relative velocity detector according to the principle can be corrected and applied to the magnetic levitation control.

請求項１乃至３に記載の磁気軸受において位置検出信号によって相対速度検出器の感度を補正する手段を備えて、位置の如何を問わず速度検出信号の出力を速度に比例するように補正することを可能にする． 4. The magnetic bearing according to claim 1, further comprising means for correcting the sensitivity of the relative speed detector based on the position detection signal, and correcting the output of the speed detection signal so as to be proportional to the speed regardless of the position. Makes possible.

請求項１乃至５に記載の磁気軸受において出力される相対速度に相当する信号を微分する装置を備え、相対速度を微分することによって磁気浮上系の相対的な加速度を知ることができ設計当上明らかな磁気軸受を構成する各部分の質量や剛性と、軸受電磁石と検出器との位置関係などから、電磁石が吸引して浮上させている力を直接的に検出することができる。 A device for differentiating a signal corresponding to the relative speed output in the magnetic bearing according to claim 1, wherein the relative acceleration of the magnetic levitation system can be known by differentiating the relative speed. From the mass and rigidity of each part constituting an obvious magnetic bearing and the positional relationship between the bearing electromagnet and the detector, it is possible to directly detect the force that the electromagnet attracts and floats.

明細書１８項に記載の手段で磁気軸受の動作している力を検出が可能となり、磁気軸受などで軸受部分と浮上部分の一方か両方の剛性が低い場合や、軸受支持点が多数にのぼる場合に、装置全体の応力歪を検出できるので、良好な制御が可能になて、大型の磁気浮上装置や高速回転の磁気軸受の性能向上に利用できる。 It is possible to detect the operating force of the magnetic bearing with the means described in the specification 18, and when the rigidity of one or both of the bearing portion and the floating portion is low in the magnetic bearing or the like, or there are many bearing support points. In this case, since the stress strain of the entire apparatus can be detected, good control can be performed, and it can be used for improving the performance of a large-sized magnetic levitation apparatus or a high-speed rotating magnetic bearing.

明細書１８項に記載の相対速度を微分する操作は、相対速度検出器が原理的検出法による検出器であることによって初めて成立する。位置出器の出力の２階微分は理論上では可能であるが、ノイズの障害を受けやすく殆ど実現できないが、相対速度検出器の出力を微分して、明細書１９項に記載の制御を行うことは容易である。 The operation for differentiating the relative speed described in the specification 18 is realized only when the relative speed detector is a detector based on the principle detection method. The second-order differentiation of the output of the positioner is theoretically possible, but it is susceptible to noise disturbance and can hardly be realized. However, the output of the relative speed detector is differentiated and the control described in item 19 is performed. It is easy.

請求項１乃至５に記載の磁気軸受において、速度検出装置の出力信号を積分する装置を備え，不定積分された出力の積分定数に位置測定装置の出力の時間平均値を与えれば，前記不定積分の出力に積分定数として回転軸の現在位置の平均値を与えることができて、速度信号積分により位置出力が得られるので、位置検出器の出力に代るか、それと複合して制御を行うことができる。 6. The magnetic bearing according to claim 1, further comprising a device for integrating the output signal of the speed detection device, wherein the time constant value of the output of the position measuring device is given to the integral constant of the indefinitely integrated output. The average value of the current position of the rotation axis can be given as an integral constant to the output of, and the position output can be obtained by speed signal integration, so control can be performed in place of or combined with the output of the position detector Can do.

請求項１乃至７に記載の磁気軸受において回転軸の位置と位置の変化速度の検出器または、いずれかを浮上用電磁石の磁化が作用する面の反対側を代表とする電磁石の磁化が作用する面以外の面に配置して前記電磁石の漏洩磁束または励磁電流を供給する給電線からの静電及び電磁ノイズを遮ることができる場所に検出器を装着する。 8. The magnetic bearing according to claim 1, wherein the position of the rotating shaft and the position change speed detector or the electromagnet magnetization represented by the opposite side of the surface on which the magnetization of the levitation electromagnet acts act. The detector is mounted in a place where it can be arranged on a surface other than the surface to block electrostatic and electromagnetic noise from a power supply line that supplies leakage flux or excitation current of the electromagnet.

請求項１乃至７に記載の磁気軸受において回転軸の位置と位置の変化速度の検出器または、いずれかを浮上用電磁石の磁化が作用する面の反対側を代表とする電磁石の磁化が作用する面以外の面で、前記磁気軸受電磁石の吸引力の力学的中心に近づくように配置した請求項１乃至７に記載の磁気軸受により、磁気軸受で支持する場合に磁気軸受の機能上の中心位置に検出器を装着することを可能にする。 8. The magnetic bearing according to claim 1, wherein the position of the rotating shaft and the position change speed detector or the electromagnet magnetization represented by the opposite side of the surface on which the magnetization of the levitation electromagnet acts act. The center position on the function of the magnetic bearing when supported by the magnetic bearing by the magnetic bearing according to claim 1, which is arranged so as to approach the mechanical center of the attractive force of the magnetic bearing electromagnet on a surface other than the surface. Makes it possible to mount a detector.

速度検出装置を備えて位置変化速度を直接的に検出するので、磁気浮上制御ループの安定化に必要な位置変化速度を、位置出器の出力を微分して作り出す必要がなく、速度信号に、微分に際して発生するノイズによる影響と、ノイズを除去しようとすると避けられない信号の伝達遅延による影響を除去して、磁気軸受の制御特性を改善して磁気浮上制御ループの動作を安定化できる。 Since the position change speed is detected directly with the speed detection device, it is not necessary to create the position change speed necessary for stabilizing the magnetic levitation control loop by differentiating the output of the positioner. By removing the influence of noise generated during differentiation and the influence of signal transmission delay that cannot be avoided when removing the noise, the control characteristics of the magnetic bearing can be improved and the operation of the magnetic levitation control loop can be stabilized.

非接触で電気信号を得ることを目的とする相対速度検出器は物理現象として古くから知られて居り、原理的に良質の出力信号が得られるので磁気浮上制御ループの速度帰還入力として用いれば、磁気軸受等の浮上安定化に効果的である。 Relative speed detectors aimed at obtaining electrical signals without contact have long been known as a physical phenomenon, and in principle a good quality output signal can be obtained, so if used as a speed feedback input for a magnetic levitation control loop, It is effective for stabilization of levitation of magnetic bearings.

しかし物理現象を直接的に利用する速度検出器は検出対象物との距離によって検出感度が変化し、一般に近づくと感度が高くなり、遠ざかると感度が低くなる傾向を示すので回転体の直径上に相対速度検出器気を回転体の直径上の２箇所に配置して両者の検出出力を加算することによって位置による検出感度の変化を著しく軽減する効果が得られる。 However, speed detectors that use physical phenomena directly change the detection sensitivity depending on the distance to the object to be detected. In general, the sensitivity increases when approaching, and the sensitivity decreases when moving away. By arranging the relative velocity detectors at two positions on the diameter of the rotating body and adding the detection outputs of both, the effect of remarkably reducing the change in detection sensitivity due to the position can be obtained.

また，相対位置検出器の出力によって相対速度検出器の検出感度を修正する方法でも効果が得られる． An effect can also be obtained by correcting the detection sensitivity of the relative velocity detector based on the output of the relative position detector.

位置検出器の出力の２階微分を行えば、理論的に加速度が算出されて、上記の軸受力を求められるが、微分ノイズなどが原因となって現実的には困難であり、現在までは試みられていないが、相対速度検出器の出力は原理的にノイズが少ないので微分するのに都合がよい上に、加速度を得るために２階微分の必要がなくなる。 If the second-order differentiation of the output of the position detector is performed, the acceleration is theoretically calculated and the above bearing force can be obtained. However, it is actually difficult due to differential noise, etc. Although not tried, the output of the relative velocity detector is low noise in principle, so that it is convenient to differentiate and there is no need for second order differentiation to obtain acceleration.

磁気軸受で支持する回転体の回転数数が極めて高い場合、歳差運動を伴う場合、剛性の低い回転体の場合、多数の軸受を備える回転体の場合などに適用する磁気軸受などの磁気浮揚装置に制御の安定化の可能性をもたらした。 Magnetic levitation such as magnetic bearings applied to rotating bodies supported by magnetic bearings when the number of rotations is extremely high, accompanying precession, rotating bodies with low rigidity, or rotating bodies with multiple bearings The device brought the possibility of control stabilization.

請求項１乃至５に記載の磁気軸受において出力される相対速度に相当する信号を積分する装置を備える請求項１乃至５に記載の磁気軸受けを用いれば、位置検出信号を創生することができ、位置検出装置の出力を積分定数の決定に用いれば、位置検出装置の出力よりも質の高い位置検出信号が得られる。 A position detection signal can be created by using the magnetic bearing according to any one of claims 1 to 5 provided with a device that integrates a signal corresponding to the relative velocity output in the magnetic bearing according to any one of claims 1 to 5. If the output of the position detection device is used to determine the integral constant, a position detection signal with higher quality than the output of the position detection device can be obtained.

請求項１乃至６に記載の磁気軸受において出力される相対速度に相当する信号を微分する装置を備える請求項１乃至６に記載の磁気軸受を用いれば、速度検出装置の出力を微分して力を求めることができるので、柔軟な回転体の場合や、磁気軸受の支持点が多数に上る場合に、制御を容易にする効果が得られる。 The magnetic bearing according to claim 1, further comprising a device for differentiating a signal corresponding to the relative speed output in the magnetic bearing according to claim 1. Therefore, the effect of facilitating the control can be obtained in the case of a flexible rotating body or when the number of support points of the magnetic bearing is increased.

請求項１乃至７に記載の磁気軸受において浮上対象物の位置や位置の変化速度の検出器を浮上用電磁石の磁化が作用する面の反対側を代表とする前記電磁石の磁化が作用する面以外の面に配置して検出器の出力にノイズが混入することを防止できる。 8. The magnetic bearing according to claim 1, wherein the position of the levitating object and the position change speed detector are other than the surface on which the magnetization of the electromagnet represented by the opposite side of the surface on which the magnetization of the electromagnet for floating acts. It is possible to prevent noise from being mixed into the output of the detector.

図１は本発明の相対速度検出器を適用して成る磁気軸受の概念を説明する実施例であって、回転軸に相当する磁性円柱１を、その両端部に吸引電磁石２，２ａを配置して吊り上げる形態の磁気浮上システムを説明している。なを、実用に供する磁気軸受では、円柱を挟んで吸引電磁石２，２ａの反対側にも吸引電磁石を設けて、それぞれ両者が必要に応じて吸引する構造になっていて、一対の吸引電磁石で１制御軸を形成する。更に、直交方向と、円柱の軸方向にも制御軸を設けて円柱の位置と姿勢を制御するのを基本形として一般に５軸制御と呼ばれている。本説明では１軸の半分を重力加速度にゆだねて、半軸を２組示して説明する。 FIG. 1 is an embodiment for explaining the concept of a magnetic bearing to which a relative speed detector according to the present invention is applied, in which a magnetic cylinder 1 corresponding to a rotating shaft is arranged and attracting electromagnets 2 and 2a are arranged at both ends thereof. A magnetic levitation system in the form of lifting up is described. In a magnetic bearing for practical use, an attracting electromagnet is provided on the opposite side of the attracting electromagnets 2 and 2a with a cylinder interposed therebetween, and both are attracted as necessary. One control axis is formed. Furthermore, control of the position and orientation of the cylinder by providing control axes in the orthogonal direction and the axial direction of the cylinder is generally called 5-axis control. In this description, half of one axis is subjected to gravitational acceleration, and two sets of half axes are shown.

位置検出装置３，３ａは磁性円柱１の位置に相当する電気信号を出力する。４，４ａは従来の磁気軸受では使用されていなかった速度検出装置であって、磁気軸受に対する円柱の相対速度に相当する電気信号を出力する。 The position detection devices 3 and 3 a output an electric signal corresponding to the position of the magnetic cylinder 1. Reference numerals 4 and 4a denote speed detection devices that have not been used in conventional magnetic bearings, and output an electrical signal corresponding to the relative speed of the cylinder with respect to the magnetic bearing.

出力増幅器を兼ねる演算増幅器５，５ａを加算器として用いて位置と速度による制御、即ち、ＰＤ制御を行って円柱１を安定に静止状態で浮上させる。詳細な説明は省くが、それぞれの検出装置３，４、３ａ，４ａの加算抵抗６，７、６ａ，７ａを介して演算増幅器に入力され、帰還抵抗８，８ａを介して帰還される帰還入力と平衡してリファレンス電圧と同じ値を保って円柱１を、それぞれの磁気軸受２，２ａによって安定に浮上させる。なを、リファレンス電圧は図１でｒｅｆ．の記号で示した。 The operational amplifiers 5 and 5a that also serve as output amplifiers are used as adders to perform control based on position and speed, that is, PD control, so that the cylinder 1 is stably floated in a stationary state. Although not described in detail, a feedback input that is input to the operational amplifier through the addition resistors 6, 7, 6a, and 7a of the respective detection devices 3, 4, 3a, and 4a and fed back through the feedback resistors 8 and 8a. The cylinder 1 is stably floated by the respective magnetic bearings 2 and 2a while maintaining the same value as the reference voltage in equilibrium. The reference voltage is ref. Indicated by the symbol.

図２は従来から実施されている磁気軸受の概念を説明する実施例であって、図１の説明図から、更に一方の磁気軸受が省略されている。従来技術では、速度検出措置を備えないで、位置検出装置の円柱１の位置に相当する電気信号を微分して位置検出装置の出力信号に替えている。演算増幅器９及び、抵抗１１，１２，１３の機能は図１の実施例の説明と同じである。演算増幅器９、キャパシタ１４、抵抗１５で微分回路を構成して、位置の変化速度として演算増幅器１０に入力している。説明は省くが、微分回路の動作には実務上の問題が多く、応答周波数大域幅やノイズの発生などが障害になって、磁気軸受が技術的に困難を伴うものとされてきた。 FIG. 2 is an embodiment for explaining the concept of a conventional magnetic bearing, in which one of the magnetic bearings is omitted from the explanatory view of FIG. In the prior art, an electric signal corresponding to the position of the column 1 of the position detection device is differentiated and replaced with an output signal of the position detection device without providing a speed detection measure. The functions of the operational amplifier 9 and the resistors 11, 12, and 13 are the same as those in the embodiment of FIG. A differential circuit is configured by the operational amplifier 9, the capacitor 14, and the resistor 15, and is input to the operational amplifier 10 as a position change speed. Although explanation is omitted, there are many practical problems in the operation of the differentiation circuit, and the response frequency bandwidth and noise generation have become obstacles, and magnetic bearings have been considered technically difficult.

明細書３６に記載の欠陥が放置されていた理由の一つには、速度検出装置の適当な物を磁気軸受関係技術者が発見できなかった所にある。以下、公知の理論と公知の技術を用いて成した本発明の、速度検出装置に関して詳細に説明をする。 One of the reasons why the defect described in the specification 36 has been neglected is that an engineer related to a magnetic bearing could not find an appropriate thing for the speed detection device. Hereinafter, the speed detection apparatus according to the present invention, which is made using a known theory and a known technique, will be described in detail.

図３のＢは速度検出装置を磁気軸受に適用した一実施例の該当部分の斜視図、Ａは、同断面図である。円柱１の電極１６，１６ａ，１７，１７ａ，１８，１８ａ，１９，１９ａに対向する部分は連続で導電性表面を備えるものとすると、例えば、電極１６と１６ａののそれぞれの端子２０と２０ａから見ると、キャパシタを形成している。該キャパシタの静電容量はそれぞれ電極１６，１６ａと円柱１の対向面積と、距離と、雰囲気の誘電率とによって決定され、端子２０と２０ａとの間の静電容量は、電極１６，１６ａによってそれぞれ形成されたキャパシタを直列に接続した値となり、円柱１、電極１６，１６ａの電位は無関係である。但し、理論上は対向する電極の面積が充分に大きいか、電極間の距離が充分に小さい場合に限られるが、速度検出装置として考える場合には静電容量を修正する係数を用意すれば充分である。 FIG. 3B is a perspective view of a corresponding portion of an embodiment in which the speed detection device is applied to a magnetic bearing, and FIG. 3A is a sectional view thereof. If the portions of the cylinder 1 facing the electrodes 16, 16a, 17, 17a, 18, 18a, 19, 19a are continuous and have conductive surfaces, for example, from the respective terminals 20 and 20a of the electrodes 16 and 16a As seen, a capacitor is formed. The capacitance of the capacitor is determined by the facing area of the electrodes 16 and 16a and the cylinder 1, the distance, and the dielectric constant of the atmosphere, and the capacitance between the terminals 20 and 20a is determined by the electrodes 16 and 16a. Each of the formed capacitors is connected in series, and the potentials of the cylinder 1 and the electrodes 16 and 16a are irrelevant. Theoretically, however, this is limited to the case where the area of the opposing electrodes is sufficiently large or the distance between the electrodes is sufficiently small, but when considering it as a speed detection device, it is sufficient to prepare a coefficient for correcting the capacitance. It is.

ストレイキャパシタンス、リークカレント等を無視して、理想的な状態を仮定すれば、電極２０，２０ａ、２１，２１ａ、２２，２２ａ、２３，２３ａ、それぞれの間に同電位差の電圧を与えるべく直流電源に接続して、円柱を半径方向に移動させると各電極間にそれぞれ速度成分に対応する電流が流れる。 If an ideal state is assumed ignoring stray capacitance, leakage current, etc., a direct current power source is used to apply a voltage having the same potential difference between the electrodes 20, 20a, 21, 21a, 22, 22a, 23, 23a. When the cylinder is moved in the radial direction, currents corresponding to velocity components flow between the electrodes.

図４は前記速度成分に対応する電流を検出して増幅する回路の一施例を示すが、回路に使用する演算増輻器２４，２５は入力抵抗値が高くバイアス電流の少ない演算増幅器を使用することが好ましい。本実施例では基準電圧端子３５を信号接地として、端子３６にプラス、３７にマイナスの絶対値の等しい直流電圧を印加する。電極１６には、演算増幅器２４の出力端子から帰還抵抗２７を介して充電電流が流れて、端子３６に印加された電圧に達する、電極１６ａの電圧も同様にして端子３７の電圧に達する。 FIG. 4 shows an example of a circuit for detecting and amplifying a current corresponding to the speed component. The operational amplifiers 24 and 25 used in the circuit use operational amplifiers having a high input resistance value and a small bias current. It is preferable to do. In this embodiment, the reference voltage terminal 35 is set as signal ground, and a DC voltage having the same absolute value is applied to the terminal 36 and plus to 37. A charging current flows from the output terminal of the operational amplifier 24 to the electrode 16 via the feedback resistor 27 and reaches the voltage applied to the terminal 36. The voltage of the electrode 16a similarly reaches the voltage of the terminal 37.

円柱の移動によって電極１６，１６ａと円柱１との間の静電容量が変化して、帰還抵抗２７，２８を介して電流が流れて、円柱の変位速度が演算増幅器２４，２５の出力電圧に変換される。演算増幅器２６によって信号レベルを整えて端子３８に変位速度信号を出力する。 The capacitance between the electrodes 16 and 16a and the cylinder 1 changes due to the movement of the cylinder, and a current flows through the feedback resistors 27 and 28, so that the displacement speed of the cylinder becomes the output voltage of the operational amplifiers 24 and 25. Converted. A signal level is adjusted by the operational amplifier 26 and a displacement speed signal is output to the terminal 38.

図５の速度検出装置Ｃ，Ｄは本発明の電磁型速度検出装置の実施例であって、速度検出装置Ｃはサーチコイル４０にバイアス磁界を与えるために永久磁石４１を備えてマグネットヨーク３９を励磁し、速度検出装置Ｄはサーチコイル４０ａにバイアス磁界を与えるために励磁コイル４３を備え、励磁コイル４３には、記載しない定電流電源によって制御された一定電流を流してマグネットヨーク４２を励磁する。その結果、Ｃ、Ｄ、の速度検出装置は全く同一の速度検出動作を行うことになる。 Speed detectors C and D in FIG. 5 are embodiments of the electromagnetic speed detector of the present invention. The speed detector C includes a permanent magnet 41 and a magnet yoke 39 for applying a bias magnetic field to the search coil 40. The excitation speed detector D is provided with an excitation coil 43 for applying a bias magnetic field to the search coil 40a. The excitation coil 43 is supplied with a constant current controlled by a constant current power source (not shown) to excite the magnet yoke 42. . As a result, the C, D speed detection devices perform exactly the same speed detection operation.

Ｃ、Ｄいずれもマグネットヨーク３９，４２の磁束は、ほぼ、マグネットヨークの端面と円柱表面との距離、即ち、ギャップ長さで決まり、磁束はギャップの長さの分数関数で表され、明細書３９乃至４１項に記載の静電型速度検出装置と同じ動作特性を示す。 In both C and D, the magnetic flux of the magnet yokes 39 and 42 is almost determined by the distance between the end surface of the magnet yoke and the cylindrical surface, that is, the gap length, and the magnetic flux is expressed as a fractional function of the gap length. The same operational characteristics as those of the electrostatic speed detection device according to the items 39 to 41 are exhibited.

図６は、本発明の電磁型速度検出装置を磁気軸受けに適用する場合の一回路例であって、演算増幅器４４によってサーチコイルに誘導された速度に対応する誘導電流を帰還抵抗４６で電圧に変換して端子４７に出力する。入力抵抗４５はゲインの設定と温度補償などの機能を持ち、端子４８は信号接地線である。 FIG. 6 is an example of a circuit when the electromagnetic speed detecting device of the present invention is applied to a magnetic bearing, and an induced current corresponding to the speed induced in the search coil by the operational amplifier 44 is converted into a voltage by the feedback resistor 46. The data is converted and output to the terminal 47. The input resistor 45 has functions such as gain setting and temperature compensation, and the terminal 48 is a signal ground line.

静電型速度検出装置、電磁誘導型速度検出装置のいずれも明細書４３項に記載のように円柱１の表面からの距離の分数関数として速度検出感度が変化するので、磁気軸受けを制御する上で不都合な場合が多い。図７に図３Ｂを再掲するが、電極１６，１６ａ、１７，１７ａと、１８，１８ａ、１９，１９ａを、それぞれ一対にして磁気軸受制御の一軸の速度検出装置を構成すれば速度検出出力の位置による変化を減少させることができる。 Since both the electrostatic speed detection device and the electromagnetic induction speed detection device change the speed detection sensitivity as a fractional function of the distance from the surface of the cylinder 1 as described in Item 43, the magnetic bearing is controlled. In many cases, it is inconvenient. FIG. 3B is shown again in FIG. 7. If a pair of electrodes 16, 16 a, 17, 17 a and 18, 18 a, 19, 19 a is paired to form a single-axis speed detection device for magnetic bearing control, speed detection output can be obtained. Changes due to position can be reduced.

図９は、図７の電極１６，１６ａ，１７，１７ａと、１８，１８ａ、１９，１９ａを、を一対として位置による感度の変化を減少させて、特性を改善する回路の一例であって、図４の回路を２組、位相を反転して加算するものである。４９は信号設置、端子５０は正直流電圧、端子５１は負の直流電圧、端子５２は速度検出出力である。 FIG. 9 is an example of a circuit that improves the characteristics by reducing the change in sensitivity depending on the position of a pair of the electrodes 16, 16a, 17, 17a and 18, 18a, 19, 19a of FIG. Two sets of the circuit of FIG. 4 are added with their phases inverted. 49 is a signal installation, terminal 50 is a positive DC voltage, terminal 51 is a negative DC voltage, and terminal 52 is a speed detection output.

図８は誘導型検出装置を各制御軸に一対ずつ設けたものであって、Ｅは検出装置のバイアス磁界の励磁を直列に配置した例で、Ｆは励磁を並列に行い、戻りの磁路は拡散さた例であるが、磁気軸受周辺の構造によって、いずれかの方法を選択する。 FIG. 8 shows a pair of inductive detection devices provided on each control axis. E is an example in which the excitation of the bias magnetic field of the detection device is arranged in series, F is the excitation in parallel, and the return magnetic path. Is a diffused example, but either method is selected depending on the structure around the magnetic bearing.

図１０は、図８の誘導型速度検出装置の一対を接続した例であって、位置による速度検出の感度変化を除去する効果は大きく、回路は極めて簡単である。演算増幅器５４、抵抗５５，５６で構成する増幅器で所定の電圧に整えられて端子５８に出力する。端子５７は信号設置である。 FIG. 10 shows an example in which a pair of the inductive speed detection devices of FIG. 8 are connected, and the effect of removing the sensitivity change in speed detection due to the position is great, and the circuit is very simple. An amplifier composed of an operational amplifier 54 and resistors 55 and 56 is adjusted to a predetermined voltage and output to a terminal 58. Terminal 57 is a signal installation.

図１１は、速度検出装置の特性を評価するために、図４に示した回路と位置検出装置を併設して、円柱１に偏心量を与えて回転させた時の位置検出装置の出力５９と、速度検出装置の出力６０を同時に記録したものであって、速度検出装置の出力６０に著しい波形歪が認められるが、図９の回路を用いると、速度検出波形は、図１２の波形６２になり、図１１の出力波形６０に比べて著しく改善された。図１２の波形６１は、併設した位置検出装置の出力波形である。 FIG. 11 shows an output 59 of the position detection device when the column detector 1 is rotated by giving an eccentricity to the cylinder 1 in order to evaluate the characteristics of the speed detection device. The output 60 of the speed detection device is recorded at the same time, and significant waveform distortion is recognized in the output 60 of the speed detection device. However, when the circuit of FIG. 9 is used, the speed detection waveform is changed to the waveform 62 of FIG. Thus, the output waveform 60 of FIG. 11 is remarkably improved. A waveform 61 in FIG. 12 is an output waveform of the position detection apparatus provided together.

図１３は、図１０の回路に位置検出装置を併設して、明細書４９項に記載の説明と同様に円柱１に偏心量を与えて回転させた時の併設された位置検出装置の出力６３と、速度検出装置の出力６４を同時に記録したもので、速度検出装置の出力５６に、殆ど波形歪が認められず、図１０の回路による効果が明らかに認められる。 FIG. 13 shows an output 63 of the position detection device provided when the position detection device is added to the circuit of FIG. 10 and the column 1 is rotated by giving an eccentric amount in the same manner as described in Item 49. The output 64 of the speed detector is recorded at the same time, and almost no waveform distortion is observed in the output 56 of the speed detector, and the effect of the circuit of FIG. 10 is clearly recognized.

図１４は、円柱１の軸方向に相当する、図１７に示す検出装置１０２ａまたは、図１８の検出装置１０９ａのように、速度検出装置を対にして装着することが困難な場合などに用いる手段であって、位置検出装置３の出力を用いて速度検出装置４の出力の非直線性を補正する回路の一例である。演算増幅器６７の帰還ループに制御非線形素子７１を配置したが、補正は順方向回路で行うこともできる。端子７２は位置検出出力、端子７３は補正された速度検出出力、端子７４は信号接地端子である。 14 corresponds to the axial direction of the cylinder 1 and is used when it is difficult to mount a pair of speed detection devices, such as the detection device 102a shown in FIG. 17 or the detection device 109a shown in FIG. In this example, the output of the position detection device 3 is used to correct the non-linearity of the output of the speed detection device 4. Although the control nonlinear element 71 is arranged in the feedback loop of the operational amplifier 67, the correction can be performed by a forward circuit. Terminal 72 is a position detection output, terminal 73 is a corrected speed detection output, and terminal 74 is a signal ground terminal.

図１５は、速度検出装置４の出力を積分する回路を備える本発明の一実施例であって、演算増幅器７７、速度信号入力抵抗８０、積分キャパシタ８１で構成する積分器に位置信号入力抵抗８２と、直流ゲインを設定する帰還抵抗８３を付加してあり、積分器の出力は円柱１の速度が零の時に位置検出出力に相当する値を出力し、速度を積分した位置に相当する信号を重畳して出力することができる。この方法を用いれば位置検出信号の周波数応答特性に対する制約が無くなり、高い精度の磁気軸受の制御が可能になる。端子８４は直接の位置検出出力であり、端子８５が速度検出出力、端子８６が積分回路による高精度位置検出出力、端子８７が信号接地である。 FIG. 15 shows an embodiment of the present invention provided with a circuit for integrating the output of the speed detection device 4. The position signal input resistor 82 is added to the integrator composed of the operational amplifier 77, the speed signal input resistor 80, and the integration capacitor 81. And a feedback resistor 83 for setting a DC gain, and the output of the integrator outputs a value corresponding to the position detection output when the velocity of the cylinder 1 is zero, and a signal corresponding to the position obtained by integrating the velocity. Superimposed and output. If this method is used, the restriction on the frequency response characteristics of the position detection signal is eliminated, and the magnetic bearing can be controlled with high accuracy. A terminal 84 is a direct position detection output, a terminal 85 is a speed detection output, a terminal 86 is a high-accuracy position detection output by an integration circuit, and a terminal 87 is a signal ground.

図１６は、速度検出装置４の出力を微分する回路を備える本発明の一実施例であって、演算増幅器９０、微分キャパシタ９３、帰還抵抗９４で微分器を構成している。端子９５は位置検出出力であり、端子９６は速度検出出力、端子９７は速度を微分した出力、端子９８が信号接地である。 FIG. 16 shows an embodiment of the present invention provided with a circuit for differentiating the output of the speed detection device 4, and an operational amplifier 90, a differential capacitor 93, and a feedback resistor 94 constitute a differentiator. A terminal 95 is a position detection output, a terminal 96 is a speed detection output, a terminal 97 is an output obtained by differentiating the speed, and a terminal 98 is signal ground.

明細書５３項に記載の速度を微分した出力は円柱１の加速度であって、速度微分回路を備えることによって、円柱１が吸引電磁石２を初めとする磁気軸受電磁石から受けている力の他に、円柱１の撓み、ジャイロモーメントなどによる力の総和を知ることができ、例えば円柱１の撓み量が大きい場合や、慣性モーメントが大きい場合、回転角速度が大きい場合、軸受が多数設けられている場合、磁気軸受を据え付ける架台の剛性が低い場合などの、従来技術による磁気軸受では困難とされていた種類の回転体などの磁気浮揚が容易に実現できる。 The output obtained by differentiating the speed described in the specification 53 is the acceleration of the cylinder 1, and by providing a speed differentiation circuit, in addition to the force that the cylinder 1 receives from the magnetic bearing electromagnet including the attraction electromagnet 2. The total force due to the deflection of the cylinder 1 and the gyro moment can be known. For example, when the deflection amount of the cylinder 1 is large, when the moment of inertia is large, when the rotational angular velocity is large, or when many bearings are provided In addition, magnetic levitation of a rotating body of a kind that has been considered difficult with conventional magnetic bearings, such as when the rigidity of a gantry on which the magnetic bearings are installed is low, can be easily realized.

図１７は、円柱１に同心状に空洞部分９９を設けて、空洞部分９９の内面１００の位置または速度、または、位置と速度を検出するべく、空洞部分９９に検出装置１０２，１０２ａを設けて、磁気軸受電磁石１０３及び励磁コイル１０４から漏洩する磁束が、検出装置１０２，１０２ａに影響するのを遮蔽する構造の本発明の一実施例を示す図である。磁気軸受電磁石をスイッチング制御する場合には、軸受部分から発生するノイズのレベルが高くなるので、図１７に示す構造並びに検出装置の配置は検出器の誘導ノイズ低減のために有効である。１０１は円柱１に嵌装された円筒状の磁性体、１０５は検出装置を支持する構造体を示す。 In FIG. 17, a hollow portion 99 is provided concentrically in the cylinder 1, and detection devices 102 and 102 a are provided in the hollow portion 99 in order to detect the position or velocity of the inner surface 100 of the hollow portion 99 or the position and velocity. FIG. 3 is a diagram showing an embodiment of the present invention having a structure that shields magnetic flux leaking from the magnetic bearing electromagnet 103 and the exciting coil 104 from affecting the detection devices 102 and 102a. In the case of switching control of the magnetic bearing electromagnet, the level of noise generated from the bearing portion becomes high. Therefore, the structure and arrangement of the detection device shown in FIG. 17 are effective for reducing the induction noise of the detector. Reference numeral 101 denotes a cylindrical magnetic body fitted to the column 1, and 105 denotes a structure that supports the detection device.

図１８は、図１７に示す磁気軸受の構造を半径方向において反転した構造の本発明の一実施例を示す図である。円柱１に同心状に空洞部分１０７を設けて、空洞部分１０７に磁気軸受電磁石１１０及び励磁コイル１１１を配置した構造の本発明の一実施例を示す図である。１０８は円柱１の空洞部分１０７の内面に嵌装された円筒状の磁性体、１１２は磁気軸受電磁石と検出装置を支持する構造体である。 FIG. 18 is a view showing an embodiment of the present invention having a structure in which the structure of the magnetic bearing shown in FIG. 17 is inverted in the radial direction. FIG. 3 is a view showing an embodiment of the present invention having a structure in which a hollow portion 107 is provided concentrically on a cylinder 1 and a magnetic bearing electromagnet 110 and an exciting coil 111 are arranged in the hollow portion 107. Reference numeral 108 denotes a cylindrical magnetic body fitted on the inner surface of the hollow portion 107 of the column 1, and 112 denotes a structure that supports the magnetic bearing electromagnet and the detection device.

この様に、磁気軸受電磁石と同心上で、異なる半径上に検出装置を配置することによって、軸受電磁石が発生する吸引力の軸方向の分布の中心部分に検出装置を配置することが可能になって、磁気軸受制御回路または制御プログラムの単純化が可能になる。 In this manner, by arranging the detection devices concentrically with the magnetic bearing electromagnet and on different radii, it becomes possible to arrange the detection device in the central portion of the axial distribution of the attractive force generated by the bearing electromagnet. Thus, the magnetic bearing control circuit or the control program can be simplified.

明細書３４乃至５７に記載の実施例では制御手段を示す場合にはアナログ技術を以って表現したが、簡単に説明を行うことが目的であって、制御手段を限定するものではなく、ディタルプロセッサーを用いてソフトウェアによって本発明を実施してもよい。 In the embodiments described in the specification 34 to 57, the control means is expressed by analog technology. However, the description is provided for the sake of simplicity, and the control means is not limited. The present invention may be implemented by software using a tall processor.

本発明の磁気軸受の構成要素を示す図である。 It is a figure which shows the component of the magnetic bearing of this invention. 従来の技術による磁気軸受制御を示す図である。 It is a figure which shows the magnetic bearing control by a prior art. Ａは本発明の速度検出装置を磁気軸受に適用した一実施例の該当部分の斜視図、Ｂは断面図である。 A is a perspective view of a corresponding part of an embodiment in which the speed detection device of the present invention is applied to a magnetic bearing, and B is a sectional view. 前記速度成分に対応する電流を検出して増幅する回路の実施例を示す図である。 It is a figure which shows the Example of the circuit which detects and amplifies the electric current corresponding to the said speed component. 速度検出装置Ｃ，Ｄは電磁型速度検出装置の実施例を示す図である。 Speed detection devices C and D are diagrams showing an embodiment of an electromagnetic speed detection device. 電磁型速度検出装置を磁気軸受けに適用する場合の回路例を示す図である。 It is a figure which shows the circuit example in the case of applying an electromagnetic type | mold speed detection apparatus to a magnetic bearing. 図３Ｂを再掲した図である。 It is the figure which reproduced FIG. 3B again. 誘導型検出装置を各制御軸に一対ずつ設けた例を示す図である。 It is a figure which shows the example which provided the induction | guidance | derivation type | mold detection apparatus one by one on each control axis | shaft. 図７に示した電極を一対として位置による感度の変化を減少させた例を示す図である。 It is a figure which shows the example which reduced the change of the sensitivity by a position by making the electrode shown in FIG. 7 into a pair. 図８に示した誘導型速度検出装置の一対を接続した例を示す図である。 It is a figure which shows the example which connected a pair of the induction | guidance | derivation type speed detection apparatuses shown in FIG. 速度検出装置の特性を評価するために測定した波形を示す図である。 It is a figure which shows the waveform measured in order to evaluate the characteristic of a speed detection apparatus. 出力波形が著しく改善されたのを示す図である。 It is a figure which shows that the output waveform was remarkably improved. 位置検出装置の出力５５と、速度検出装置の出力５６を同時に記録した図である。 It is the figure which recorded simultaneously the output 55 of the position detection apparatus, and the output 56 of the speed detection apparatus. 位置検出器５７の出力を用いて速度検出装置５８の出力の非直線性を補正する回路の一例を示す図である。 It is a figure which shows an example of the circuit which correct | amends the nonlinearity of the output of the speed detection apparatus 58 using the output of the position detector 57. FIG. 速度検出装置５８の出力を積分する回路を備える実施例を示す図である。 It is a figure which shows an Example provided with the circuit which integrates the output of the speed detection apparatus. 速度検出装置５８の出力を微分する回路を備える実施例を示す図である。 It is a figure which shows an Example provided with the circuit which differentiates the output of the speed detection apparatus. 図１７は、円柱に同心状に空洞部分を設けて、該空洞部分に検出装置を設ける構造の一実施例を示す図である。 FIG. 17 is a diagram showing an embodiment of a structure in which a hollow portion is provided concentrically on a cylinder and a detection device is provided in the hollow portion. 図１８は、円柱に同心状に空洞部分を設けて、該空洞部分に磁気軸受電磁石を配置した構造の実施例を示す図である。 FIG. 18 is a diagram showing an embodiment of a structure in which a hollow portion is provided concentrically on a cylinder and a magnetic bearing electromagnet is disposed in the hollow portion.

Claims

磁気吸引力により浮揚支持されている回転軸の軸受に対する相対位置を検出する位置検出装置と、回転軸の軸受に対す相対位置変化速度を検出する相対速度検出装置を備える磁気軸受。 A magnetic bearing comprising: a position detection device that detects a relative position of a rotary shaft that is levitated and supported by a magnetic attractive force; and a relative speed detection device that detects a relative position change speed of the rotary shaft with respect to the bearing.

請求項１に記載の速度検装置が浮揚支持されている前記回転軸または前記回転軸に取り付けられた導電性部分と、導電性部分に対向して軸受側に設けた電極によって形成された蓄電器と、蓄電器に直流電圧を印加する回路と蓄電器の電極間距離の変化速度に従って蓄電電器の電極に出入する電流または、蓄電器の電極間電圧を検出する回路を備えることを特徴とする請求項１に記載の磁気軸受。 The accumulator formed by the rotating shaft on which the speed detecting device according to claim 1 is levitated or a conductive portion attached to the rotating shaft, and an electrode provided on the bearing side facing the conductive portion, 2. The circuit according to claim 1, further comprising: a circuit that applies a DC voltage to the capacitor and a circuit that detects a current flowing in and out of the electrode of the capacitor or a voltage between the electrodes of the capacitor in accordance with a change speed of a distance between the electrodes of the capacitor. Magnetic bearings.

請求項１に記載の速度検装置が浮揚支持されている前記回転軸または回転軸に取り付けられた磁性体部分と、磁性体部分と電磁的に結合する状態で軸受側に設けたサーチコイルと、前記サーチコイルにバイアス磁界を与える手段と、サーチコイルと前記回転体の距離の変化速度に従ってサーチコイルに誘導された電流または電圧を検出する回路を備えることを特徴とする請求項１に記載の磁気軸受。 The rotary shaft on which the speed detection device according to claim 1 is levitated, or a magnetic part attached to the rotary shaft, a search coil provided on the bearing side in an electromagnetically coupled state with the magnetic part, 2. The magnetism according to claim 1, further comprising means for applying a bias magnetic field to the search coil, and a circuit for detecting a current or a voltage induced in the search coil according to a change speed of a distance between the search coil and the rotating body. bearing.

請求項１乃至３に記載の磁気軸において、１軸の相対速度を検出する為に一対の検出器を差動動作をするような関係位置に装着して、前記相対速度の差動出力を得る回路を備え、速度検出装置の出力の波形歪を減少させる機能を備える請求項１乃至３に記載の磁気軸受。 4. The magnetic shaft according to claim 1, wherein a pair of detectors are mounted at relative positions for differential operation in order to detect a relative speed of one axis to obtain a differential output of the relative speed. The magnetic bearing according to claim 1, further comprising a circuit and having a function of reducing waveform distortion of an output of the speed detection device.

請求項１乃至３に記載の磁気軸受において位置検出装置の出力信号を用いて速度検出器の感度を補正する装置を備え、速度検出装置の波形歪を減少させる機能を備える請求項１乃至３に記載の磁気軸受。 The magnetic bearing according to any one of claims 1 to 3, further comprising a device for correcting the sensitivity of the speed detector using an output signal of the position detection device, and a function of reducing waveform distortion of the speed detection device. The magnetic bearing described.

請求項１乃至５に記載の磁気軸受において出力される相対速度に相当する信号を積分する装置を備える請求項１乃至３に記載の磁気軸受け。 The magnetic bearing according to any one of claims 1 to 3, further comprising a device that integrates a signal corresponding to a relative speed output from the magnetic bearing according to any one of claims 1 to 5.

請求項１乃至５に記載の磁気軸受において出力される相対速度に相当する信号を微分する装置を備える請求項１乃至４に記載の磁気軸受。 The magnetic bearing according to any one of claims 1 to 4, further comprising a device for differentiating a signal corresponding to a relative speed output in the magnetic bearing according to any one of claims 1 to 5.

請求項１乃至７に記載の磁気軸受において回転軸の位置と位置の変化速度の検出器を浮上用電磁石の磁化が作用する面の反対側を代表とする電磁石の磁化が作用する面以外の面で、前記磁気軸受電磁石の吸引力の力学的中心に近づくように配置した請求項１乃至７に記載の磁気軸受。 8. The magnetic bearing according to claim 1, wherein the surface of the rotating shaft and the position change speed detector are surfaces other than the surface on which the magnetization of the electromagnet represented by the opposite side of the surface on which the magnetization of the levitation electromagnet acts. The magnetic bearing according to claim 1, wherein the magnetic bearing is disposed so as to approach a mechanical center of an attractive force of the magnetic bearing electromagnet.