JPS60190697A - Control system of magnetic bearing in turbo molecular pump - Google Patents

Control system of magnetic bearing in turbo molecular pump

Info

Publication number
JPS60190697A
JPS60190697A JP4635784A JP4635784A JPS60190697A JP S60190697 A JPS60190697 A JP S60190697A JP 4635784 A JP4635784 A JP 4635784A JP 4635784 A JP4635784 A JP 4635784A JP S60190697 A JPS60190697 A JP S60190697A
Authority
JP
Japan
Prior art keywords
rotor shaft
power
motor
molecular pump
magnetic bearing
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.)
Pending
Application number
JP4635784A
Other languages
Japanese (ja)
Inventor
Toshiaki Kawashima
敏明 川島
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Seiko Seiki KK
Original Assignee
Seiko Seiki KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Seiko Seiki KK filed Critical Seiko Seiki KK
Priority to JP4635784A priority Critical patent/JPS60190697A/en
Publication of JPS60190697A publication Critical patent/JPS60190697A/en
Pending legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C32/00—Bearings not otherwise provided for
    • F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
    • F16C32/0406—Magnetic bearings
    • F16C32/044—Active magnetic bearings
    • F16C32/0444—Details of devices to control the actuation of the electromagnets
    • F16C32/0457—Details of the power supply to the electromagnets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C32/00—Bearings not otherwise provided for
    • F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
    • F16C32/0406—Magnetic bearings
    • F16C32/044—Active magnetic bearings
    • F16C32/0442—Active magnetic bearings with devices affected by abnormal, undesired or non-standard conditions such as shock-load, power outage, start-up or touchdown
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2360/00—Engines or pumps
    • F16C2360/44—Centrifugal pumps
    • F16C2360/45—Turbo-molecular pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C39/00—Relieving load on bearings
    • F16C39/02—Relieving load on bearings using mechanical means

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
  • Non-Positive Displacement Air Blowers (AREA)

Abstract

PURPOSE:To eliminate a battery for protecting the rotor shaft of a turbo molecular pump by feeding the power regenerated from a motor to respective bearing upon interruption of power to a motor for driving the rotor shaft. CONSTITUTION:The power source section 8 of a turbo molecular pump is comprised of a stabilized power source 20, a magnetic bearing control circuit 22, a power interruption detector 23 and a capacitor 24 for storing the regenerative power and feeding to a magnetic bearing control circuit 22. Upon power interruption, regenerative power from the motor is fed to respective bearing. Consequently, abrupt contact between the rotor shaft and the dry bearing simultaneous with power interruption can be avoided to prevent the impact and the vibration resulting in the elimination of a battery for protecting the rotor shaft.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、ターボ分子ポンプのロータ軸を浮揚状態に軸
受する磁気軸受の制御方式に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control system for a magnetic bearing that supports a rotor shaft of a turbo-molecular pump in a floating state.

（従来技術） 先に本出願人が開発した磁気浮揚方式のターボ分子ポン
プを第１図に示す。(Prior Art) FIG. 1 shows a magnetic levitation type turbomolecular pump previously developed by the applicant.

このポンプは、ロータハウジング１内を上下【こ貫通づ
るロータ軸２の外周に高周波モータ３を設り、かつその
上部には、ロータ軸２の外周ｔこ、９０°ずつの間隔で
設けられた電磁石４を配置し、また、ロータ軸２の底面
は、ロータ軸２を下方に吸引する永久磁石５を設置Ｊ、
この永久磁石と対向して〇−タハウジング１０周縁には
電磁石６を設けである。This pump has a high-frequency motor 3 installed on the outer periphery of a rotor shaft 2 that passes through the rotor housing 1 up and down. An electromagnet 4 is disposed, and a permanent magnet 5 is disposed on the bottom of the rotor shaft 2 to attract the rotor shaft 2 downward.
An electromagnet 6 is provided on the periphery of the outer housing 10 facing this permanent magnet.

そして、電Ｗｔｌ　？Ｅｉ　６を励磁することによって
、ロータ軸２およびこれに保持されたロータアッセンブ
リＲはその自重および永久磁石５の吸引力に抗して浮揚
状態となり、かつ電磁石４を励ｗ１することにより軸心
に保持される。つまり、各電磁石４゜６により磁気軸受
が構成され、ロータ軸２は非接触状態に軸受される。And Den Wtl? By energizing Ei 6, the rotor shaft 2 and the rotor assembly R held thereon become in a floating state against its own weight and the attractive force of the permanent magnet 5, and by exciting the electromagnet 4 w1, the rotor shaft 2 and the rotor assembly R held thereon are brought into a floating state. Retained. In other words, each electromagnet 4.degree. 6 constitutes a magnetic bearing, and the rotor shaft 2 is supported in a non-contact manner.

そして、高周波モータ３および電１１石４．６は外装ハ
ウジングに設けられたコネクタ７を介して電源部８に接
続され、この電源部８から給電を受（Ｊることによって
、ロータ軸２を浮揚状態に高速で回転駆動する。The high-frequency motor 3 and the electric current 4.6 are connected to a power supply unit 8 via a connector 7 provided in the exterior housing, and receive power from the power supply unit 8 to levitate the rotor shaft 2. drive to rotate at high speed.

なお、１１は電磁石４とロータ軸外周との離間距離を検
出づるための磁気←ンサ、１２はロータ軸２の浮揚位置
を検出する磁気センサであり、これら各センサの検出出
力によって各電磁石４，６をフィードバック制御し、ロ
ータ軸２を軸心に保ら、かつ所定の浮揚位置に保つよう
にしている。In addition, 11 is a magnetic sensor for detecting the separation distance between the electromagnet 4 and the outer circumference of the rotor shaft, and 12 is a magnetic sensor for detecting the floating position of the rotor shaft 2. The detection output of each of these sensors causes the electromagnet 4, 6 is feedback-controlled to maintain the rotor shaft 2 at its axial center and at a predetermined floating position.

またロータ＠２の外周部には上下に保護用のドライベア
リング９．１０が設【ノられている。ドライベアリング
９，１０は通常は非接触状態であり、電１１ｉｆ！８か
らの給電が断たれたどきに、ロータ軸２がドライベアリ
ング９．１０上に落下し、これらに軸受される構成どな
っている。Further, dry bearings 9 and 10 for protection are provided on the upper and lower sides of the outer circumference of the rotor @2. The dry bearings 9 and 10 are normally in a non-contact state, and the electric 11if! When the power supply from 8 is cut off, the rotor shaft 2 falls onto dry bearings 9 and 10 and is supported by these.

しかしながら、０−タアッセンブリＲは、モータの人さ
さどこれを駆！ＩＪ　７するに必要な１ヘルクに比べて
、非常に大きな慣性モーメン］・を持っており。However, the O-ta assembly R is not the driver of the motor! It has a very large moment of inertia compared to the 1 herk required for IJ7.

しかもロータアッセンブリＲの回転速度は貞空中で５０
００Ｏｒ　、ｐ　、ｍと、極めて高速、かつ非接触状態
で回転しているために、回転中に給電が断たれた場合に
、ロータ軸２が急速に保護用ドライベアリング９，１０
に接触し、大きな騒音を伴う振動、焼き付け、摩耗等を
起こし、１幾械寿命を著しく損う場合がある。Moreover, the rotation speed of rotor assembly R is 50 in pure air.
Since the rotor shaft 2 rotates at an extremely high speed and in a non-contact state at 00Or, p, and m, if the power supply is cut off during rotation, the rotor shaft 2 will rapidly move to the protective dry bearings 9, 10.
Contact with the machine may cause vibrations accompanied by loud noises, seizure, wear, etc., which may significantly shorten the life of the machine.

このための対策としては、電源部８にバッテリを内蔵さ
け、このバッテリで回路をバックアップして保１−Ｊる
ようにしているが、メンテナンス。As a countermeasure for this, a battery is built into the power supply section 8, and the circuit is backed up and maintained with this battery, but maintenance is required.

交換などの煩わしさを伴う。It involves the hassle of replacing it.

（発明の目的） 本発明は、前記のバッテリを不要とし、かつ停電時には
、ロータ軸の回転がある程度までに落ちた状態でロータ
軸をドライベア１リングに軸受でさるようにすることを
目的とする。(Objective of the Invention) The object of the present invention is to eliminate the need for the above-mentioned battery, and to enable the rotor shaft to be mounted on the dry bearing 1 ring with a bearing in a state where the rotation of the rotor shaft has decreased to a certain level in the event of a power outage. .

（発明の構成） 前記目的を達成するために、本発明は、［１−２軸の回
転駆動用モータの入力電源断時に、該モータより回生さ
れる電力を各軸受に給電づるＪ、うにしたことを特徴と
する。(Structure of the Invention) In order to achieve the above object, the present invention provides a system for supplying electric power regenerated from the motor to each bearing when the input power to the rotational drive motor for the 1st and 2nd axes is cut off. It is characterized by

（実施例） 第２図は本発明に係る磁気軸受の制御方式を示Ｊ′もの
である。なお、ターボ分子ポンプのロータ駆動部分の構
成は従来と同一なので、その同一箇所には同一符号を付
して説明を行なう。(Embodiment) FIG. 2 shows a control system for a magnetic bearing according to the present invention. The configuration of the rotor driving portion of the turbo molecular pump is the same as that of the conventional one, so the same parts will be described with the same reference numerals.

図において、電源部８は安定化電源装置２０と、モータ
回転制御装置２１と、磁気軸受制御回路２２と、外部電
源（ＡＣ２００Ｖ）の停電を検出する停電検出器２３と
、回生電力をためて前記磁気軸受制御回路２２に供給Ｊ
るためのコンデンサ２４とを備えている。In the figure, the power supply unit 8 includes a stabilizing power supply device 20, a motor rotation control device 21, a magnetic bearing control circuit 22, a power failure detector 23 that detects a power failure of an external power source (AC200V), and a power failure detector 23 that stores regenerated power. Supplied to the magnetic bearing control circuit 22
It is equipped with a capacitor 24 for

通常の運転時、すなわち外部電源が供給されている場合
には、モータ回転制御装置２１に対し、回転電力１１が
、また磁気軸受制御回路２２に対しコンデンサ２４を介
して駆動ミノＪＩ２が供給される。During normal operation, that is, when external power is supplied, the rotational power 11 is supplied to the motor rotation control device 21, and the drive minnow JI2 is supplied to the magnetic bearing control circuit 22 via the capacitor 24. .

したがって、外部電源が給電されている状態ではモータ
３が所要の回転数で回転し続け、かつ電磁石４，６から
なる磁気軸受が作動し、センサ１１．１２の検知出力に
応じた位置にロータ軸２を浮揚さける。Therefore, while the external power supply is being supplied, the motor 3 continues to rotate at the required rotation speed, and the magnetic bearing consisting of the electromagnets 4 and 6 operates, and the rotor shaft is positioned in accordance with the detection outputs of the sensors 11 and 12. Avoid levitating 2.

このような状態のときに、外部電源の給電が断たれると
、停電検出器２３がこれを検出し、モータ回転制御装置
２１に回生指令信号（Ａ　’）を送出する。When the external power supply is cut off in such a state, the power failure detector 23 detects this and sends a regeneration command signal (A') to the motor rotation control device 21.

この信号を受４ノで、モータ回転制御回路２１は切り替
わり、前記モータ３から回生電力（Ｉａ）を安定化電源
装置２０に回生づる。そして、安定化電源装置２０から
はこの回生電力をコンデン（）２４を介して軸受制御回
路２２に送り、これによって各磁気軸受４および６は各
センサ１１．１２の検知出力に応じた位置にロータ軸２
を保持した状態を保つ。Upon receiving this signal, the motor rotation control circuit 21 switches and regenerates the regenerated power (Ia) from the motor 3 to the stabilized power supply device 20. This regenerated power is then sent from the stabilized power supply device 20 to the bearing control circuit 22 via the condenser (24), whereby each magnetic bearing 4 and 6 is moved to a position corresponding to the detection output of each sensor 11, 12 when rotating the rotor. Axis 2
maintain the state in which it is held.

なお、ロータ軸２はモータ３の回生制動作用により抵抗
を受けて徐々に回転が落ち、ついには回転が停止Ｊるが
、１＆気軸軸受制御路２２には、コンアン４ノの容量に
応じた時間分荏延した状態で給電されたままの状態であ
るから、その回転数低下のわりには磁気軸受は本来の機
能を保った状態を射［持し、回転が完全に停止づるかあ
るいは極めて回転速度が低い段階でロータ軸２を保持づ
るに足る磁力を消失し、その結果ロータ軸２は衝撃等を
伴うことなく保護用ドライベアリング９，１０上に移さ
れるのである。。Note that the rotor shaft 2 gradually slows down due to resistance due to the regenerative braking action of the motor 3, and eventually stops rotating. Since the power is still being supplied for an extended period of time, the magnetic bearing maintains its original function even though the rotation speed decreases, and the rotation either stops completely or rotates extremely rapidly. At a low speed, the magnetic force sufficient to hold the rotor shaft 2 disappears, and as a result, the rotor shaft 2 is transferred onto the protective dry bearings 9, 10 without any impact or the like. .

なお、前記モータの種類としては誘導モータ。The type of motor mentioned above is an induction motor.

同期モータ、直流モータの何れであっても良く、回生電
力はこれらのモータを発電機として使うことができる。The motor may be either a synchronous motor or a DC motor, and these motors can be used as a generator for regenerative power.

（発明の効果） 木琵明の制御方式は以上のように構成されているので、
従来の磁気軸受のように停電と同時にロータ軸が急激に
ドライベアリングと接触Ｊることがなく、極めて低い回
転数あるいは停止した段階でドライベアリング側に受け
渡されるので、澗撃や振動あるいは高速回転による焼き
付【ノ、序耗等がなく、回転部分の損耗や破壊を防止で
きる。(Effects of the invention) Since the control system of Mokubimei is configured as described above,
Unlike conventional magnetic bearings, the rotor shaft does not suddenly come into contact with the dry bearing at the same time as a power outage, and the rotor shaft is transferred to the dry bearing at an extremely low rotation speed or when it has stopped. There is no seizure, wear and tear, and wear and tear on rotating parts can be prevented.

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

第１図はターボ分子ポンプおよび電源部の（構成を承り
説明図、第２図は本発明の電気的構成を示す説明図であ
る。 ２・・・ロータ ３・・・モータ ４．６・・・電磁石（磁気軸受） ２０・・・安定化電源装置 ２１・・・モータ回転制御回路 ２２・・・磁気軸受制御回路 ２３・・・停電検出器 Ｉ　＋　、　’Ｉ　２・・・駆動電力 （Ｉａ　）、Ｉ′（ａ　）・・・回生電力以上 出願人　しイコー精機株式会社 代理人　最　上　務　ニでべ ζパ。 こと。Fig. 1 is an explanatory diagram showing the configuration of a turbo molecular pump and a power supply section, and Fig. 2 is an explanatory diagram showing the electrical configuration of the present invention. 2...Rotor 3...Motor 4.6... - Electromagnet (magnetic bearing) 20... Stabilized power supply device 21... Motor rotation control circuit 22... Magnetic bearing control circuit 23... Power outage detector I +, 'I 2... Drive power (Ia ), I'(a)...Applicant for regenerative power and above, and Iko Seiki Co., Ltd. Agent Mogami Nidebe ζPa.

Claims (1)

【特許請求の範囲】[Claims] （１）ロータ軸の径方向および軸方向を磁気軸受で浮揚
状態に軸受し、かつ磁気軸受の電源断時に、保護用ドラ
イベアリングによりロータ軸を回転自在に受けるように
したターボ分子ポンプにおいて。 前記ロータ軸の回転駆動用モータの入力電源断時に、該
モータより回生される電力を各軸受に給電するようにし
たことを特徴とするターボ分子ポンプにＪり（ブる磁気
軸受の制御方式。(1) A turbo molecular pump in which the rotor shaft is supported in a floating state in the radial and axial directions by magnetic bearings, and the rotor shaft is rotatably supported by a protective dry bearing when the magnetic bearing is powered off. A control system for magnetic bearings in a turbo molecular pump, characterized in that when the input power to the motor for rotationally driving the rotor shaft is cut off, the electric power regenerated from the motor is supplied to each bearing.
JP4635784A 1984-03-09 1984-03-09 Control system of magnetic bearing in turbo molecular pump Pending JPS60190697A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4635784A JPS60190697A (en) 1984-03-09 1984-03-09 Control system of magnetic bearing in turbo molecular pump

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4635784A JPS60190697A (en) 1984-03-09 1984-03-09 Control system of magnetic bearing in turbo molecular pump

Publications (1)

Publication Number Publication Date
JPS60190697A true JPS60190697A (en) 1985-09-28

Family

ID=12744892

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4635784A Pending JPS60190697A (en) 1984-03-09 1984-03-09 Control system of magnetic bearing in turbo molecular pump

Country Status (1)

Country Link
JP (1) JPS60190697A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0549004A1 (en) * 1991-12-24 1993-06-30 VARIAN S.p.A. An electronic braking device for asynchronous motors
JPH06287656A (en) * 1992-03-30 1994-10-11 Mitsui Mining & Smelting Co Ltd Device for laying copper scrap on defective casting anode
EP0681115A2 (en) * 1994-05-05 1995-11-08 The BOC Group plc Magnetic bearing circuitry
FR2747431A1 (en) * 1996-04-15 1997-10-17 Soc D Mecanique Magnetique Turbo-molecular vacuum pump used in semiconductor mfr.
WO2009037255A1 (en) * 2007-09-19 2009-03-26 Oerlikon Leybold Vacuum Gmbh Vacuum pump
JP2011055640A (en) * 2009-09-02 2011-03-17 Toshiba Mitsubishi-Electric Industrial System Corp Vertical rotary electrical machine
CN106195004A (en) * 2015-05-27 2016-12-07 珠海格力节能环保制冷技术研究中心有限公司 The control method of magnetic suspension bearing and control device
JP2021508363A (en) * 2017-11-03 2021-03-04 グリー グリーン リフリッジレイション テクノロジー センター カンパニー リミテッド オブ チューハイ Connecting wire structures for magnetic bearings, compressors, and air regulators

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5923098A (en) * 1982-07-30 1984-02-06 Hitachi Ltd Molecular turbo pump

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5923098A (en) * 1982-07-30 1984-02-06 Hitachi Ltd Molecular turbo pump

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0549004A1 (en) * 1991-12-24 1993-06-30 VARIAN S.p.A. An electronic braking device for asynchronous motors
JPH06287656A (en) * 1992-03-30 1994-10-11 Mitsui Mining & Smelting Co Ltd Device for laying copper scrap on defective casting anode
EP0681115A2 (en) * 1994-05-05 1995-11-08 The BOC Group plc Magnetic bearing circuitry
EP0681115A3 (en) * 1994-05-05 1996-10-30 Boc Group Plc Magnetic bearing circuitry.
US5649814A (en) * 1994-05-05 1997-07-22 The Boc Group Plc Driver for levitation coils of a magnetic bearing
FR2747431A1 (en) * 1996-04-15 1997-10-17 Soc D Mecanique Magnetique Turbo-molecular vacuum pump used in semiconductor mfr.
WO2009037255A1 (en) * 2007-09-19 2009-03-26 Oerlikon Leybold Vacuum Gmbh Vacuum pump
JP2011055640A (en) * 2009-09-02 2011-03-17 Toshiba Mitsubishi-Electric Industrial System Corp Vertical rotary electrical machine
CN106195004A (en) * 2015-05-27 2016-12-07 珠海格力节能环保制冷技术研究中心有限公司 The control method of magnetic suspension bearing and control device
JP2021508363A (en) * 2017-11-03 2021-03-04 グリー グリーン リフリッジレイション テクノロジー センター カンパニー リミテッド オブ チューハイ Connecting wire structures for magnetic bearings, compressors, and air regulators
US11174898B2 (en) 2017-11-03 2021-11-16 Gree Green Refrigeration Technology Center Co., Ltd. Of Zhuhai Wiring structure of magnetic suspension bearing, compressor and air conditioner

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