JP2003343676A - Friction driving device - Google Patents

Friction driving device

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Publication number
JP2003343676A
JP2003343676A JP2002151407A JP2002151407A JP2003343676A JP 2003343676 A JP2003343676 A JP 2003343676A JP 2002151407 A JP2002151407 A JP 2002151407A JP 2002151407 A JP2002151407 A JP 2002151407A JP 2003343676 A JP2003343676 A JP 2003343676A
Authority
JP
Japan
Prior art keywords
pressing
signal
speed
driven shaft
drive shaft
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
JP2002151407A
Other languages
Japanese (ja)
Inventor
Takashi Obara
隆 小原
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.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
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 Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP2002151407A priority Critical patent/JP2003343676A/en
Publication of JP2003343676A publication Critical patent/JP2003343676A/en
Pending legal-status Critical Current

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  • Manufacturing Optical Record Carriers (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a feed stage for an optical master disk exposing device which realizes highly accurate feeding, and also to provide its control device. <P>SOLUTION: A base 90 disposed on a servo mounter by air pressure is provided with columns 89 that are separated in the feeding direction and in the orthogonal direction and of which one side ends are fixed to the base 90. The other side ends of the columns 89 are fixed to a moving body 13 via a rolling bearing 114 having a sphere, a cylindrical roller, or the like in the feeding direction at its upper end. The moving body 13 is fixed to an air spindle 19 that fixes a turn table 18 in its upper part and is statically floated in the radial or thrust direction by compressed air supplied from the outside (not shown). The air spindle 19 is fixed to an optical rotary encoder 21 generally constituted by A-phase and B-phase pulses having an several thousands of outputs in one circle and a Z-phase pulse occurring once in one circle via rotation driving motor 20. The rotary encoder 21 is rotatable by a communication signal from the outside (not shown) to the rotation driving motor 20. <P>COPYRIGHT: (C)2004,JPO

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】本発明は、摩擦駆動装置に関
し、さらに詳しくは、駆動軸を回転させることにより従
動軸が固定された移動体を進退させる摩擦駆動装置に関
するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction drive device, and more particularly to a friction drive device that advances and retracts a moving body having a driven shaft fixed thereto by rotating a drive shaft.

【０００２】[0002]

【従来の技術】近年の光ディスクの高密度化にともな
い、より高解像の露光を実現するために、マスタリング
装置の光源として、従来のレーザービームに代えて電子
線等を用いた露光装置が用いられるようになり、高解像
度の露光を実現する露光装置への移行に伴って真空環境
への対応やより高精度な送りが必要になってきている。
従来、この送り機構として、光ディスク原盤露光用のス
ライドテーブル装置が用いられ、静圧軸受を介してテー
ブルを進退自在に設けたエアスライド式が多く用いられ
ている。また、テーブルの駆動手段としては、ボイスコ
イル型のリニアモータが一般的に用いられ、位置検出器
として干渉レーザ測長器やリニアスケールを使用した閉
ループ制御方式が採用されている。また、半導体検査装
置等の静止状態を必要とするものでは、送り方向の剛性
を必要とするためテーブルの駆動にボールネジ等が用い
られている。前記スライドテーブル装置の摩擦駆動機構
には、駆動軸と従動軸の交差角度を鋭角とするツイスト
ローラ方式と直角とするキャプスタン方式がある。ツイ
ストローラ方式は、駆動軸と従動軸との間の交差角を微
小にすることで、他の機構では得られない小さなリード
を実現でき、高い位置決め分解能が期待できることから
次世代の送り機構として期待され、文献、特許等が公開
されている。この摩擦駆動ステージに用いられる一般的
な制御方法として、特開平９−３１９４３７号公報に
は、静止摩擦及びすべり摩擦の補償を行うと共に、同期
制御時の軌跡を改善し、動き出すときに振動を小さくす
ることのできる摩擦補償型制御方法及び装置について開
示されている。これによると、位置指令が位置制御器に
入力され、駆動源のモータを経て位置検出器から位置出
力が得られるようになっており、位置制御器は位置比例
器、速度比例器、微分器及び積分器を具備し、電流帰還
トルク帰還、速度帰還、位置帰還の各帰還ループから構
成され、位置指令信号がアナログ信号もしくはパルス信
号として与えられる。光ディスク用原盤露光装置に用い
る送り装置では、回転テーブルの角速度を一定とするＣ
ＡＶ回転送りと線速度を一定とするＣＬＶ回転送りがあ
り、所望の位置指令信号にて回転と送りが同期して制御
されるとしている。また、一般的な方法で問題となる静
止摩擦とすべり摩擦に対する補償方法として、すべり摩
擦の補償を制御系の指令量の正負に応じてすべり摩擦の
大きさを駆動源の駆動力指令トルク指令、推力指令に対
して加減算することによって実行し、静止摩擦の補償
を、制御系の指令入力のエッジ検出に基づいて積分器出
力を変動させ、前記駆動源の駆動力指令に対して加減算
する構成としている。2. Description of the Related Art With the recent increase in density of optical discs, an exposure apparatus using an electron beam or the like as a light source of a mastering apparatus is used as a light source of a mastering apparatus in order to realize higher resolution exposure. As a result of the shift to an exposure apparatus that realizes high-resolution exposure, it is necessary to respond to a vacuum environment and feed with higher accuracy.
Conventionally, as this feeding mechanism, a slide table device for exposing an optical disk master is used, and an air slide type in which a table is provided so as to be movable back and forth via a hydrostatic bearing is often used. A voice coil type linear motor is generally used as the table driving means, and a closed loop control method using an interference laser length measuring device or a linear scale as a position detector is adopted. Further, in a semiconductor inspection device or the like that requires a stationary state, a ball screw or the like is used to drive the table because rigidity in the feed direction is required. The friction drive mechanism of the slide table device includes a twist roller system in which the intersecting angle between the drive shaft and the driven shaft is an acute angle and a capstan system in which the drive shaft and the driven shaft intersect at a right angle. The twist roller system is expected as a next-generation feed mechanism because it can realize a small lead that cannot be obtained with other mechanisms by making the crossing angle between the drive shaft and the driven shaft minute and realizes high positioning resolution. The documents and patents have been published. As a general control method used for this friction drive stage, Japanese Patent Laid-Open No. 9-319437 discloses a method of compensating for static friction and sliding friction, improving a locus at the time of synchronous control, and reducing vibration when starting movement. A friction compensation type control method and device that can be used is disclosed. According to this, a position command is input to a position controller, and a position output is obtained from a position detector via a motor of a drive source.The position controller is a position proportional device, speed proportional device, differentiator, and It is equipped with an integrator and is composed of current feedback torque feedback, velocity feedback, and position feedback feedback loops, and a position command signal is given as an analog signal or a pulse signal. In the feeding device used for the optical disk master exposure device, C which makes the angular velocity of the rotary table constant is used.
There are AV rotary feed and CLV rotary feed that keeps the linear velocity constant, and rotation and feed are controlled in synchronization with a desired position command signal. Also, as a method of compensating for static friction and sliding friction, which are problems in the general method, the sliding friction compensation is performed by adjusting the magnitude of the sliding friction according to the positive or negative of the command amount of the control system, the driving force command torque command of the drive source, The configuration is performed by adding / subtracting to / from a thrust command, and compensating for static friction by varying the integrator output based on edge detection of a command input of a control system, and adding / subtracting to / from the driving force command of the drive source. There is.

【０００３】また、特開平７−１２１２３７号公報に
は、モータの駆動軸と被位置決め部材の間に生じるすべ
りが小さくなるようにモータを駆動制御することによ
り、位置決め応答性の改善を図った摩擦駆動装置につい
て開示されている。これによると、駆動軸に設けたロー
タリエンコーダによりモータの駆動軸の回転角を測定す
ると共に、摩擦駆動ユニットの出力、すなわち、被位置
決め部材の現在位置を測長器により測定する。測定され
た駆動軸回転角と現在位置情報とから、すべり計算器に
よりすべり量を演算し、このすべり量に基づきモータの
駆動軸の回転速度に補正をかける。これにより、すべり
が小さくなるようにモータを駆動制御する構成としてい
る。また、メカ機構として公開されている従来技術とし
て、特開平８−１８４３６０号公報には、耐外乱性が高
く、速度むらがなく、安定送りが行え、また駆動源の停
止時の静止性能の向上が図れる高剛性進退装置について
開示されている。これは、軸体と、この軸体を相対的に
回転および進退自在に貫通させた進退部品とを備える。
進退部品は、その本体内に、軸体に転接する樽形のロー
ラを周方向に複数個並べて設けている。これらローラ
は、両端面でボールを介して進退部品本体と予圧板との
間に回転自在に支持される。進退部品本体とローラ端面
の少なくとも一方、および予圧板とローラ端面との少な
くとも一方は、ボールが回転自在に嵌まる円すい面状の
ボール支持凹部でボールの支持を行わせる。また、予圧
板をローラ側へ付勢すると共に円周方向に付勢する弾性
体を設けている。Further, in Japanese Patent Laid-Open No. 7-112237, friction is improved by improving the positioning response by controlling the drive of the motor so that the slip generated between the drive shaft of the motor and the positioned member is reduced. A drive device is disclosed. According to this, the rotation angle of the drive shaft of the motor is measured by the rotary encoder provided on the drive shaft, and the output of the friction drive unit, that is, the current position of the positioned member is measured by the length measuring device. The slip amount is calculated by the slip calculator from the measured drive shaft rotation angle and the current position information, and the rotational speed of the motor drive shaft is corrected based on this slip amount. Thereby, the motor is driven and controlled so that the slip is reduced. Further, as a prior art disclosed as a mechanical mechanism, Japanese Unexamined Patent Publication No. 8-184360 discloses high disturbance resistance, uniform speed, stable feeding, and improved stationary performance when the drive source is stopped. A highly rigid advancing / retreating device capable of achieving the above is disclosed. This includes a shaft body and an advancing / retreating component that penetrates the shaft body so that the shaft body can rotate and reciprocate relatively.
The advancing / retreating component is provided with a plurality of barrel-shaped rollers, which are in rolling contact with the shaft, arranged side by side in the circumferential direction in the main body. These rollers are rotatably supported between the advancing / retreating component body and the preload plate via balls at both end faces. At least one of the advancing / retreating component body and the roller end surface, and at least one of the preload plate and the roller end surface support the ball in a conical surface-shaped ball support recess into which the ball is rotatably fitted. Further, an elastic body is provided which urges the preload plate toward the roller and also urges the preload plate in the circumferential direction.

【０００４】また、特開平１１−１９５２４７号公報に
よると、速度むらが生じることなく、安定した送りを行
うことができ、外乱にも強く、分解能の向上が図れ、こ
れにより高密度の書き込みを可能とした光ディスクマス
タリング装置用スライドテーブル装置について開示され
ている。これによると、テーブルとなるスライド体を基
台に対して静圧直動軸受で静圧支持し、基台に対してス
ライド体をスライド自在に駆動する摩擦進退駆動装置を
設ける。摩擦進退駆動装置は、回転駆動される主軸と、
この主軸の回りに複数個設けられて各々傾き角度を持っ
て接するローラとを備える。そして、このローラに主軸
に対する予圧を与える予圧手段を設けている。また、特
開平１１−１９５２４８号公報には、主軸およびこれに
斜めに転接するローラを備えた摩擦進退駆動装置におい
て、回転駆動源の回転むらの影響を少なくすると共に、
回転伝達系における位相ずれを少なくし、精密な位置決
めを可能とした摩擦進退駆動装置について開示されてい
る。これは、主軸と、この主軸の外周にころがり接触し
かつ主軸に対して傾き角度をもって傾斜したローラと、
前記主軸の回転に起因して移動するローラと共に移動す
るスライド体とを有する摩擦進退駆動装置において、前
記主軸を回転させる回転駆動源と、この回転駆動源の回
転を駆動側軸から摩擦車への回転伝達で減速して主軸に
伝達する減速機とを設けたことを特徴としている。この
構成の摩擦進退駆動装置によると、主軸を回転させるこ
とにより、各ローラが主軸に対して傾き角度だけリード
角を持って回転することになり、その接触部の摩擦力に
より、スライド体を軸方向に移動させる。この場合に、
回転駆動源の回転は減速して主軸に伝達されるため、ス
ライド体の位置決め精度に対する回転駆動源の回転むら
の影響が小さくなる。また、回転駆動源の回転の伝達お
よびその減速は、駆動側軸と摩擦車との摩擦接触を介し
て行うようにしたため、バックラッシ等が生じず、これ
によっても精密な位置決めが行えるとしている。また、
文献；「ツイストローラ摩擦駆動装置を用いた超精密位
置決めシステムの開発、著者水本他、１９９５年度精密
工学会秋期大会論文集」には、空気静圧軸受により案内
されたテーブルを、両端を空気静圧軸受にて支持された
駆動軸と、その駆動軸線とわずかな交差角にて設けた従
動軸に複数の玉軸受にて従動軸回りに回動支持されたロ
ーラを設けて、約７０μｍのリードで位置決め分解能２
ｎｍを実現する旨が開示されている。Further, according to Japanese Patent Laid-Open No. 11-195247, stable feeding can be performed without causing speed irregularity, resistance to external disturbances, and improvement in resolution can be achieved, which enables high-density writing. The slide table device for an optical disc mastering device is disclosed. According to this, there is provided a friction advance / retreat drive device that supports the slide body serving as a table with respect to the base by means of static pressure linear motion bearings, and drives the slide body to slide freely with respect to the base. The friction advancing / retreating drive device includes a main shaft that is rotationally driven,
A plurality of rollers are provided around the main shaft and are in contact with each other with an inclination angle. Further, a preload means for applying a preload to the main shaft is provided to this roller. Further, in Japanese Patent Laid-Open No. 11-195248, in a friction advancing / retreating drive device including a main shaft and a roller that is slidably in contact with the main shaft, the influence of rotational unevenness of a rotational drive source is reduced, and
Disclosed is a friction advancing / retreating drive device that enables precise positioning by reducing the phase shift in the rotation transmission system. This is a main shaft and a roller which is in rolling contact with the outer periphery of the main shaft and is inclined at an inclination angle with respect to the main shaft,
In a friction advancing / retreating drive device having a slide body that moves together with a roller that moves due to rotation of the main shaft, a rotary drive source that rotates the main shaft and rotation of the rotary drive source from a drive-side shaft to a friction wheel. It is characterized in that it is provided with a speed reducer for decelerating by rotation transmission and transmitting it to the main shaft. According to the friction advancing / retreating drive device of this configuration, when the main shaft is rotated, each roller rotates with a lead angle corresponding to the inclination angle with respect to the main shaft, and the friction force of the contact portion causes the slide body to rotate. Move in the direction. In this case,
Since the rotation of the rotary drive source is decelerated and transmitted to the main shaft, the influence of rotational unevenness of the rotary drive source on the positioning accuracy of the slide body is reduced. Further, since the rotation of the rotary drive source is transmitted and decelerated by frictional contact between the drive shaft and the friction wheel, backlash does not occur, which also enables precise positioning. Also,
Reference: "Development of Ultra-precision Positioning System Using Twist Roller Friction Drive, Author Mizumoto et al., Proc. Of Autumn Meeting of 1995 Precision Engineering Society" describes a table guided by aerostatic bearings with air at both ends. A drive shaft supported by a hydrostatic bearing and a driven shaft provided at a slight crossing angle with the drive axis are provided with rollers that are rotatably supported around the driven shaft by a plurality of ball bearings. Positioning resolution 2 with lead
It is disclosed that nm is realized.

【０００５】[0005]

【発明が解決しようとする課題】前記特開平１１−１９
５２４７号公報や特開平１１−１９５２４８号公報に示
されているように、駆動モータや減速器等は全体の系に
対して遅れ要素となるため、一般的に、送り回転駆動モ
ータからステージの移動体までの伝達系の周波数特性は
１次以上の遅れ系となる。更に移動体の重量があるため
制御系のサーボ帯域ｆ１は、高くても数１０Ｈｚ程度が
限界であり、ステージ上に取り付けられた回転テーブル
に載置されるガラス板等の偏芯による回転振動のよう
に、数１０Ｈｚ帯域に外乱振動等がある場合は、サーボ
系が追従できず送り精度が悪くなる。また、従来のＰＩ
Ｄ制御方式では、サーボ系の摩擦特性を考慮した特別な
補償器を備えていないため、積分器により摩擦などの外
力に対しては位置検出出力と位置指令との偏差を０にし
て補償している。この場合、速度に応じて増加する粘性
摩擦に対しては補償を行なうことができるが、静止摩
擦、固定的なすべり摩擦についての補償は行うことがで
きない。また、特開平９−３１９４３７号公報の速度制
御系では、速度指令は速度制御器に入力され、駆動源の
モータを経て速度出力が得られるようになっており、速
度制御器は速度比例器及び積分器を備えている。この速
度制御系においても摩擦特性を考慮した補償器はなく、
同じく積分器によって摩擦などの外力に対しては速度出
力と速度指令との偏差を０にして補償している。この場
合も前記同様、速度に応じて増加する粘性摩擦に対して
は補償を行うことができるが、静止摩擦や固定的なすべ
り摩擦についての補償は行うことができない。このよう
に、静止摩擦が制御系に含まれると、モータを駆動する
ために静止摩擦に打勝つトルクが必要となる。このトル
クは積分器からトルク指令として出力されるが、静止摩
擦と同等のトルクを出力するまでに時間がかかり、動き
出すトルクを積分器が除々に大きくしてモータを回転す
るので、回転すると摩擦が変化することにより振動的に
なる。また、速度制御系においても静止摩擦が含まれる
場合には、前記と同様の問題が生じる。特に、光ディス
ク原盤露光用のスライドテーブル装置では送り速度が数
μｍ／ｓ〜数１０μｍ／ｓと極低速の送りが必要となる
ため、この精度に追従することは困難となる。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
As disclosed in Japanese Patent No. 5247 and Japanese Patent Laid-Open No. 11-195248, the drive motor, the speed reducer, and the like are delay elements with respect to the entire system, and therefore the stage is generally moved from the feed rotation drive motor. The frequency characteristic of the transmission system up to the body is a delay system of the first order or higher. Further, since the moving body is heavy, the servo band f 1 of the control system has a limit of about several tens Hz at the highest, and rotational vibration due to eccentricity of a glass plate or the like placed on a rotary table mounted on the stage. As described above, when there is a disturbance vibration or the like in the several tens Hz band, the servo system cannot follow and the feed accuracy deteriorates. In addition, conventional PI
Since the D control method does not include a special compensator considering the frictional characteristics of the servo system, the integrator compensates for the external force such as friction by setting the deviation between the position detection output and the position command to 0. There is. In this case, the viscous friction that increases with the speed can be compensated, but the static friction and the fixed sliding friction cannot be compensated. Further, in the speed control system of Japanese Patent Laid-Open No. 9-319437, the speed command is input to the speed controller and the speed output is obtained via the motor of the drive source. Equipped with an integrator. Even in this speed control system, there is no compensator considering friction characteristics.
Similarly, the integrator compensates for external force such as friction by setting the deviation between the speed output and the speed command to zero. Also in this case, similarly to the above, it is possible to compensate for viscous friction that increases with speed, but it is not possible to compensate for static friction or fixed sliding friction. Thus, when static friction is included in the control system, a torque that overcomes static friction is required to drive the motor. This torque is output from the integrator as a torque command, but it takes time to output the torque equivalent to static friction, and the integrator gradually increases the torque that starts moving to rotate the motor. It changes to become oscillatory. Further, when static friction is also included in the speed control system, the same problem as described above occurs. In particular, in a slide table device for exposing an optical disc master, it is necessary to feed at a very low feed rate of several μm / s to several tens of μm / s, and it is difficult to follow this precision.

【０００６】また、特開平８−１８４３６０号公報に開
示される構成では、ローラ端面を支持している固定板及
び対向板に各々形成される円すい面状のボール支持凹部
の機械的な位置誤差のため、リードＬを数１０μｍ位に
小さく取ることができないため、高い位置決め分解能が
得られず、狭トラックピッチでの送り精度が悪くなり露
光品質を良好に維持することが困難である。更に、同公
報では、予圧板をローラ側へ付勢すると共に円周方向に
付勢する弾性体を設ける構成としているため、ローラの
軸体に対する現在予圧量が定量的に確認できず、適正な
予圧量にするのに試行錯誤が必要となる。また、ローラ
や軸体の磨耗による経年変化に伴う予圧の再調整も困難
となり、部品交換時の予圧量再現性もなく組立性が悪く
なる。また、特開平１１−１９５２４７号公報に開示さ
れる構成では、スライド体が送り方向に動作すると、予
圧をかけられて固定されているだけで、剛性が最も低い
ローラと主軸間でその真直誤差を吸収することになるの
で、ローラの主軸に対する予圧量が移動位置とともに変
化してしまう。また、駆動軸とひとつのローラ間に働く
駆動軸方向の駆動力は、駆動軸外周とローラ間の動摩擦
係数をμ、予圧をＮとするとＦ＝μＮとなる。従って、
各々のローラと駆動軸外周で発生する駆動力にもばらつ
きを生じ、それにより各々の駆動力にもばらつきを生じ
るため、各ローラ軸芯と駆動軸とのなす角度のばらつき
と相乗して駆動軸と従動軸のローラ間ですべりを生じ、
これが、閉ループ制御の外乱となり、その結果、トラッ
クピッチ精度等が悪くなり露光品質上好ましくない影響
を与える。更に、同公報では、スライド体を基台に対し
て静圧直動軸受で静圧支持しており、また、前記文献で
は空気静圧軸受により案内されたテーブルを、両端を空
気静圧軸受にて支持する構成としているが、前記静圧軸
受は非常に高価であり装置コストが高くなるといった問
題がある。本発明は、かかる課題に鑑み、前記問題点を
生じることなく、高精度送りを実現できる摩擦駆動装
置、特に光ディスク原盤露光装置用送りステージとその
制御装置を提供することを目的とする。Further, in the structure disclosed in Japanese Patent Laid-Open No. 8-184360, a mechanical position error of the conical surface-shaped ball supporting recesses formed on the fixed plate and the opposing plate supporting the roller end face is eliminated. Therefore, since the lead L cannot be made as small as several tens of μm, a high positioning resolution cannot be obtained, the feed accuracy at a narrow track pitch deteriorates, and it is difficult to maintain good exposure quality. Further, in this publication, since the elastic body that urges the preload plate toward the roller side and urges in the circumferential direction is provided, the current preload amount of the roller shaft body cannot be quantitatively confirmed, and the proper preload amount cannot be confirmed. Trial and error is required to obtain the preload amount. In addition, it becomes difficult to readjust the preload due to secular change due to wear of the roller and the shaft body, and there is no reproducibility of the preload at the time of parts replacement, resulting in poor assembly. Further, in the configuration disclosed in Japanese Patent Application Laid-Open No. 11-195247, when the slide body moves in the feeding direction, it is only fixed by being preloaded, and the straightness error between the roller having the lowest rigidity and the spindle is reduced. Since it is absorbed, the amount of preload on the main shaft of the roller changes with the moving position. Further, the driving force in the direction of the drive shaft acting between the drive shaft and one roller is F = μN, where μ is the dynamic friction coefficient between the outer periphery of the drive shaft and the roller, and N is the preload. Therefore,
Since the driving force generated between each roller and the outer circumference of the drive shaft also varies, which causes variation in each driving force as well, the drive shaft is synergistic with the variation in the angle formed by each roller shaft core and the drive shaft. And slippage between the driven shaft roller,
This becomes a disturbance of the closed loop control, and as a result, the track pitch accuracy and the like deteriorate, which adversely affects the exposure quality. Further, in the same publication, the slide body is hydrostatically supported by a hydrostatic linear bearing with respect to the base, and in the above document, the table guided by the hydrostatic bearings has both ends as aerostatic bearings. However, there is a problem that the static pressure bearing is very expensive and the device cost is high. SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a friction drive device capable of realizing high-precision feed without causing the above-mentioned problems, particularly a feed stage for an optical disc master exposure device and a control device therefor.

【０００７】[0007]

【課題を解決するための手段】本発明はかかる課題を解
決するために、請求項１は、固定されたベースと、該ベ
ース側に回転自在に支持された駆動軸と、該駆動軸の外
径位置に所定の傾斜角度をもって円周方向に配置された
従動軸と、該従動軸により回転自在に支持され且つ前記
駆動軸の外周にころがり接触するローラと、前記駆動軸
の回転に伴って駆動軸の軸方向に移動すると共に前記従
動軸を支持する移動体と、該移動体の送り位置を検出す
る位置検出手段と、前記駆動軸の回転角度位置を検出す
る角度検出手段と、を備えた摩擦駆動装置であって、前
記駆動軸と従動軸との交差角度を自在に調整する角度調
整手段と、前記移動体を前記駆動軸の軸方向に移動する
送り指令信号と前記位置検出手段の出力信号との差信号
である速度指令信号と前記位置検出手段の出力信号を周
波数電圧変換して得られる現在速度信号との差信号に基
づいて送り駆動モータへの印加電圧を増減して前記送り
駆動モータの回転速度を制御する第１の速度サーボ制御
手段と、前記速度指令信号と現在速度信号の差信号であ
る速度偏差信号に基づいて、前記角度調整手段への印加
電圧を増減して前記従動軸の駆動軸に対する傾き角度を
調整して前記移動体の送り速度を制御する第２の速度サ
ーボ制御手段と、を備えたことを特徴とする。かかる発
明によれば、駆動軸と従動軸の交差角度を調整する角度
調整手段と、速度指令信号と現在速度信号に基づいて送
り駆動モータの回転速度を制御する第１の速度サーボ制
御手段と、速度偏差信号に基づいて角度調整手段への印
加電圧を増減して移動体の送り速度を制御する第２の速
度サーボ制御手段を設けて、数Ｈｚ程度の低域速度変動
を送り駆動モータでおこない、また数１０Ｈｚ程度の高
域速度変動を従動軸の駆動軸に対する傾き角度を調整し
て制御しているので、回転振動等の外乱振動に対しても
安定した送り制御が実現でき、送り精度の向上が図れ
る。SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a fixed base, a drive shaft rotatably supported on the base side, and an outer side of the drive shaft. A driven shaft arranged in a radial direction at a predetermined inclination angle in the circumferential direction, a roller rotatably supported by the driven shaft and in rolling contact with the outer periphery of the drive shaft, and driven by the rotation of the drive shaft. A moving body that moves in the axial direction of the shaft and supports the driven shaft; a position detecting unit that detects a feed position of the moving body; and an angle detecting unit that detects a rotational angular position of the drive shaft. A friction drive device, an angle adjusting means for freely adjusting an intersecting angle of the drive shaft and a driven shaft, a feed command signal for moving the moving body in an axial direction of the drive shaft, and an output of the position detecting means. Speed command signal, which is the difference signal from the signal And a current speed signal obtained by frequency-voltage converting the output signal of the position detecting means and a current speed signal, the applied voltage to the feed drive motor is increased or decreased to control the rotational speed of the feed drive motor. Based on a speed servo control means and a speed deviation signal which is a difference signal between the speed command signal and the current speed signal, the voltage applied to the angle adjusting means is increased or decreased to adjust the tilt angle of the driven shaft with respect to the drive axis. Second speed servo control means for controlling the feed speed of the moving body. According to this invention, the angle adjusting means for adjusting the intersecting angle of the drive shaft and the driven shaft, the first speed servo control means for controlling the rotation speed of the feed drive motor based on the speed command signal and the current speed signal, A second speed servo control means for controlling the feed speed of the moving body by increasing or decreasing the voltage applied to the angle adjusting means on the basis of the speed deviation signal is provided, and the low-range speed fluctuation of about several Hz is performed by the feed drive motor. In addition, since the high-speed velocity fluctuation of about several tens Hz is controlled by adjusting the tilt angle of the driven shaft with respect to the drive shaft, stable feed control can be realized even for disturbance vibration such as rotational vibration, and the feed accuracy can be improved. Can be improved.

【０００８】請求項２は、前記第２の速度サーボ制御手
段は、前記第１の速度サーボ制御手段のサーボ帯域をｆ
１としたときに遮断周波数ｆｃがｆｃ≧ｆ１なる関係を
満足する１次以上のハイパスフィルタ要素を有する第２
の位相補償器を備えたことを特徴とする。かかる発明に
よれば、第２の速度サーボ制御手段に、第１の速度サー
ボ制御手段のサーボ帯域をｆ１としたときに、遮断周波
数ｆｃがｆｃ≧ｆ１なる関係の１次以上のハイパスフィ
ルタ要素にて構成される第２の位相補償器を設けて、数
Ｈｚ程度の低域速度変動に対する第１の速度サーボ制御
手段と第２の速度サーボ制御手段の動作干渉を回避して
いるので、更に安定した送り制御が実現でき、送り精度
の向上が図れる。請求項３では、前記第２の速度サーボ
制御手段は、前記速度指令信号と現在速度信号に基づい
て速度偏差信号を出力する第２の差動増幅器と、前記第
２の位相補償器と、サーボ系の利得調整を行なうゲイン
調整器と、前記第２の速度サーボ制御手段のＯＮ／ＯＦ
Ｆを行う第１のスイッチと、前記角度調整手段へ操作電
圧を印加する駆動アンプと、該駆動アンプへオフセット
電圧を印加する定電圧発生手段と、を備えたことを特徴
とする。かかる発明によれば、第２の速度サーボ制御手
段は、速度偏差信号を出力する第２の差動増幅器と、第
２の位相補償器と、ゲイン調整器と、第２の速度サーボ
制御手段のＯＮ／ＯＦＦを行う第１のスイッチと、操作
電圧を印加する駆動アンプと、定電圧発生手段を設けて
いるので、数１０μｍ〜数ｍｍ程度の広いリードを実現
でき、高分解能の送りが可能となるので狭トラックピッ
チでの送り精度の向上が図れる。請求項４は、前記定電
圧発生手段は、制御を司るＣＰＵと、動作プログラムが
記憶されたＲＯＭと、データの書き込み／読み出しを行
うＲＡＭと、前記ＣＰＵの指令により前記位置検出手段
のパルス出力信号と前記角度検出手段からの１回転当た
りの原点検出信号から前記従動軸の前記駆動軸に対する
現在傾き角度を算出する演算部と、該演算部の算出結果
がゼロとなるように補正電圧を演算する補正演算部と、
該補正演算出力をアナログ信号に変換するＤ／Ａ変換器
と、を備えたことを特徴とする。かかる発明によれば、
定電圧発生手段は、ＣＰＵ、ＲＯＭ、ＲＡＭ、ＣＰＵの
指令により現在傾き角度を算出する第１の演算部と、そ
の結果から補正電圧を演算する補正演算部と、その補正
演算出力をアナログ信号に変換する第２のＤ／Ａ変換器
を設けているので、数１０μｍ〜数ｍｍ程度の広いリー
ドをソフトウェアにより実現できるので、フレキシブル
な制御と駆動電圧の安定的な供給を行なうことができ
る。According to a second aspect of the present invention, the second speed servo control means sets the servo band of the first speed servo control means to f.
A second high-pass filter element having a cut-off frequency fc satisfying a relation that fc ≧ f 1
The phase compensator is provided. According to this invention, when the second speed servo control means has a servo band f 1 of the first speed servo control means, the cut-off frequency fc has a relation of fc ≧ f 1 and a high-pass filter of the first order or higher. Since the second phase compensator composed of the elements is provided to avoid the operation interference of the first speed servo control means and the second speed servo control means with respect to the low-range speed fluctuation of about several Hz, Further, stable feed control can be realized, and feed accuracy can be improved. According to a third aspect of the present invention, the second speed servo control means outputs a speed deviation signal based on the speed command signal and the current speed signal, a second differential amplifier, the second phase compensator, and a servo. A gain adjuster for adjusting the gain of the system, and ON / OF of the second speed servo control means
It is characterized by comprising a first switch for performing F, a drive amplifier for applying an operating voltage to the angle adjusting means, and a constant voltage generating means for applying an offset voltage to the drive amplifier. According to this invention, the second speed servo control means includes the second differential amplifier that outputs the speed deviation signal, the second phase compensator, the gain adjuster, and the second speed servo control means. Since the first switch for turning on / off, the drive amplifier for applying the operation voltage, and the constant voltage generating means are provided, a wide lead of several tens of μm to several mm can be realized, and high-resolution feed is possible. Therefore, it is possible to improve the feed accuracy at a narrow track pitch. According to a fourth aspect of the present invention, the constant voltage generating means has a CPU for controlling, a ROM in which an operation program is stored, a RAM for writing / reading data, and a pulse output signal of the position detecting means according to a command from the CPU. And a calculation unit that calculates the current tilt angle of the driven shaft with respect to the drive shaft from the origin detection signal per one rotation from the angle detection unit, and the correction voltage is calculated so that the calculation result of the calculation unit becomes zero. A correction calculator,
And a D / A converter for converting the correction calculation output into an analog signal. According to this invention,
The constant voltage generating means is a CPU, ROM, RAM, a first calculation unit that calculates the current tilt angle according to a command from the CPU, a correction calculation unit that calculates a correction voltage from the result, and the correction calculation output as an analog signal. Since the second D / A converter for conversion is provided, a wide lead of several tens of μm to several mm can be realized by software, so that flexible control and stable supply of driving voltage can be performed.

【０００９】請求項５は、前記角度調整手段は、前記従
動軸の一端を球面軸受にて支持すると共にその支持の中
心に回動支持点を備え、前記従動軸の他端を自由支持点
とするために、前記従動軸に設けたローラを前記回動支
持点を支点として前記駆動軸の外周に押圧する第１の弾
性体及び前記駆動軸外周の接線方向に押圧する第２の弾
性体を備え、前記回動支持点を挟んで前記ローラと反対
側に、前記第１の弾性体の反力による前記回動支持点周
りのモーメント力を相殺する方向に前記従動軸を押圧す
るように伸縮する第２の圧電素子と前記従動軸の押圧力
により変形する第２の変形部と該第２の変形部の変形量
を検出する第２の変形量測定手段と第２の押圧板とから
構成される第２の押圧手段と、を備えたことを特徴とす
る。かかる発明によれば、角度調整手段は、駆動軸の外
周にころがり接触するローラを設けた従動軸の片端を球
面軸受にて支持して、回動支持点を支点として駆動軸外
周に押圧する自由支持とし、前記の回動支持点を挟んで
ローラと反対側に、駆動軸外周の接線方向で第１の弾性
体の反力による回動支持点周りのモーメント力を相殺す
るように伸縮する第２の押圧手段を構成しているので、
簡単な構造にて従動軸の駆動軸に対する傾き角度を調整
する角度調整手段を実現でき、装置コストを安価にでき
る。請求項６は、前記角度調整手段は、前記従動軸の一
端を球面軸受にて支持すると共にその支持の中心に回動
支持点を備え、前記従動軸の他端を自由支持点とするた
めに、前記従動軸に設けたローラを前記回動支持点を支
点として前記駆動軸の外周に押圧する第１の弾性体及び
前記駆動軸外周の接線方向に押圧する第２の弾性体を備
え、前記回動支持点を挟んで前記ローラと反対側に、前
記駆動軸の軸線と直角方向で前記第１の弾性体の反力に
よる前記回動支持点周りのモーメント力を相殺する方向
に前記従動軸を押圧するように伸縮する第１の圧電素子
と第１の押圧板とから構成される第１の押圧手段と、前
記駆動軸外周の接線方向で前記第２の弾性体の反力によ
る前記回動支持点周りのモーメント力を相殺する方向に
前記従動軸を押圧するように伸縮する第２の圧電素子と
第２の押圧板から構成される第２の押圧手段と、を備え
たことを特徴とする。かかる発明によれば、前記請求項
５に加えて、回動支持点を挟んでローラと反対側に、駆
動軸の軸線と直角方向で第１の弾性体の反力による回動
支持点周りのモーメント力を相殺する様に第１の押圧手
段を設けているので、駆動軸に対するローラの押圧調整
が容易となり組立性が向上する。According to a fifth aspect of the present invention, the angle adjusting means supports one end of the driven shaft by a spherical bearing and has a pivotal support point at the center of the support, and the other end of the driven shaft is a free support point. In order to achieve this, a first elastic body that presses the roller provided on the driven shaft to the outer circumference of the drive shaft with the rotation support point as a fulcrum and a second elastic body that presses the roller in the tangential direction of the outer circumference of the drive shaft are provided. And expanding and contracting on the side opposite to the roller across the rotation support point so as to press the driven shaft in a direction that cancels the moment force around the rotation support point due to the reaction force of the first elastic body. A second piezoelectric element, a second deformable portion that is deformed by the pressing force of the driven shaft, second deformation amount measuring means for detecting the amount of deformation of the second deformable portion, and a second pressing plate. And a second pressing unit that is provided. According to this invention, the angle adjusting means supports one end of the driven shaft, which is provided with a roller in rolling contact with the outer periphery of the drive shaft, with a spherical bearing, and presses the rotation support point to the outer periphery of the drive shaft as a fulcrum. As a support, the first expansion and contraction is performed on the opposite side of the roller with the rotation support point interposed therebetween in the tangential direction of the outer periphery of the drive shaft so as to cancel out the moment force around the rotation support point due to the reaction force of the first elastic body. Since it constitutes the pressing means of 2,
An angle adjusting means for adjusting the tilt angle of the driven shaft with respect to the drive shaft can be realized with a simple structure, and the device cost can be reduced. According to a sixth aspect of the present invention, the angle adjusting means supports one end of the driven shaft by a spherical bearing and has a rotation support point at the center of the support, and the other end of the driven shaft is a free support point. A first elastic body that presses the roller provided on the driven shaft against the outer periphery of the drive shaft with the rotation support point as a fulcrum, and a second elastic body that presses the roller in the tangential direction of the outer periphery of the drive shaft, The driven shaft is provided on the side opposite to the roller with the rotation support point interposed therebetween, and in a direction perpendicular to the axis of the drive shaft in a direction canceling out the moment force around the rotation support point due to the reaction force of the first elastic body. And a first pressing unit composed of a first pressing plate that expands and contracts so as to press, and the rotation by the reaction force of the second elastic body in a tangential direction of the outer periphery of the drive shaft. The driven shaft is pressed in a direction to cancel the moment force around the dynamic support point. A second piezoelectric element and the second pressing means and a second pressing plate for urchin stretch, characterized by comprising a. According to this invention, in addition to the fifth aspect, on the side opposite to the roller sandwiching the rotation supporting point, the rotation supporting point around the rotation supporting point by the reaction force of the first elastic body in the direction perpendicular to the axis of the drive shaft is provided. Since the first pressing means is provided so as to cancel the moment force, the pressing adjustment of the roller with respect to the drive shaft is facilitated and the assemblability is improved.

【００１０】請求項７は、前記第２の押圧手段は、前記
Ｄ／Ａ変換器と、前記第２の変形量測定手段と、前記Ｄ
／Ａ変換器の出力信号である押圧伸縮設定信号と前記第
２の変形量測定手段の出力信号である現在押圧伸縮量を
比較してサーボ動作を行う第２のサーボ制御手段と、を
備えたことを特徴とする。かかる発明によれば、第２の
押圧手段をこのように構成することにより、第２の圧電
素子に非線形特性があってもサーボ制御により補償さ
れ、正確で自在な交差角を形成できるので、安定した送
り制御が実現でき、送り精度の向上が図れる。請求項８
は、前記第１の押圧手段は、一定電圧を発生する定電圧
回路と、一方の端子を０Ｖ他方の端子に前記定電圧回路
の出力信号が接続され外部信号によりＯＮ／ＯＦＦする
切換スイッチと、第１の押圧板の第１の変形部に設けた
第１の変形量測定手段と、前記切換スイッチの出力信号
である押圧伸縮設定信号と前記第１の変形量測定手段の
出力信号である現在押圧伸縮量とを比較してサーボ制御
する第１のサーボ制御手段と、を備えたことを特徴とす
る。かかる発明によれば、第１の押圧手段をこのように
構成することにより、適正な予圧条件に瞬時に設定で
き、ローラや駆動軸の磨耗による経年変化に伴う予圧の
再調整も容易となり、部品交換時の予圧量再現性も良好
となり組立性の向上が図れる。According to a seventh aspect, the second pressing means is the D / A converter, the second deformation amount measuring means, and the D / A converter.
And a second servo control means for performing a servo operation by comparing a pressing expansion / contraction setting signal which is an output signal of the A / A converter and a current pressing expansion / contraction amount which is an output signal of the second deformation amount measuring means. It is characterized by According to this invention, by configuring the second pressing means in this way, even if the second piezoelectric element has a non-linear characteristic, it is compensated by the servo control and an accurate and free crossing angle can be formed, so that it is stable. The feed control can be realized and the feed accuracy can be improved. Claim 8
The first pressing means includes a constant voltage circuit for generating a constant voltage, a switch for turning on / off an external signal by connecting an output signal of the constant voltage circuit to one terminal of 0 V and the other terminal, The first deformation amount measuring means provided on the first deforming portion of the first pressing plate, the press expansion / contraction setting signal which is an output signal of the changeover switch, and the output signal of the first deformation amount measuring means are present. A first servo control means for performing servo control by comparing the amount of press expansion and contraction. According to this invention, by configuring the first pressing means in this way, it is possible to instantly set an appropriate preload condition, and it becomes easy to readjust the preload due to secular change due to wear of the roller and the drive shaft. The reproducibility of the preload at the time of replacement is also good, and the assemblability can be improved.

【００１１】請求項９は、前記第１の押圧手段は、ＣＰ
Ｕからのデジタル信号をアナログ信号に変換する１つの
Ｄ／Ａ変換器と、前記第１の押圧板と前記回動支持点と
ローラ間にあって前記従動軸の押圧方向への変形量を検
出する第３の変形量測定手段と、前記１つのＤ／Ａ変換
器の出力信号である押圧設定信号と前記第３の変形量測
定手段の出力信号である現在押圧量とを比較してサーボ
制御する第４のサーボ制御手段と、を備えたことを特徴
とする。かかる発明によれば、第１の押圧手段をこのよ
うに構成することにより、ベースに固定される案内機構
の固定部である支柱の送り方向真直と、駆動軸の送り方
向真直に誤差を生じて組み立てが行われても、移動体が
送り方向に動作した時の組立誤差による予圧変動を生じ
ることがなくなり、各々のローラと駆動軸外周で発生す
る駆動力にもばらつきを発生しないので、長ストローク
の駆動でも安定した送り動作が実現でき、送り制御精度
及び組立性の向上が図れるとともに簡便な案内機構で構
成できるので装置が安価となる。請求項１０は、出力手
段は、複数の圧電素子への押圧設定信号を独立に与える
ためにＣＰＵからのデジタル信号をアナログ信号に変換
する複数のＤ／Ａ変換器と、複数の前記第３の変形量測
定手段と、前記複数のＤ／Ａ変換器の出力信号である押
圧設定信号と前記複数の第３の変形量測定手段の出力信
号である現在押圧量とを比較してサーボ制御する第５の
サーボ制御手段と、を備えていることを特徴とする。か
かる発明によれば、移動体が送り方向に動作した時の組
立誤差による予圧変動を生じることがなくなり、各々の
ローラと駆動軸外周で発生する駆動力にもばらつきを発
生しないので、長ストロークの駆動でも安定した送り動
作が実現でき、送り制御精度及び組立性の向上が図れる
とともに簡便な案内機構で構成できるので装置が安価と
なる。請求項１１は、前記従動軸は、前記第１の押圧手
段の押圧点と前記回動支持点間距離をＬ１、前記第１の
押圧手段の押圧点とローラ間距離をＬ２とした時に、Ｌ
２＞Ｌ１の条件を満足する前記第３の変形量測定手段変
位拡大機構を形成していることを特徴とする。かかる発
明によれば、従動軸は、第１の押圧手段に用いる圧電素
子の伸縮量が小さくても大きな押圧ストロークが得られ
るので、駆動軸回りに配置する機構を小さくでき、装置
の小型化が図れる。In a ninth aspect, the first pressing means is CP
A D / A converter for converting a digital signal from U into an analog signal; and a first D / A converter, which is located between the first pressing plate, the rotation support point and the roller, and which detects the amount of deformation of the driven shaft in the pressing direction. A third deformation amount measuring means, a pressing setting signal which is an output signal of the one D / A converter, and a current pressing amount which is an output signal of the third deformation amount measuring means are compared to perform servo control. 4 servo control means. According to this invention, by constructing the first pressing means in this way, an error occurs between the feed direction straightness of the support column, which is the fixed portion of the guide mechanism fixed to the base, and the feed direction straightness of the drive shaft. Even after assembly, the preload fluctuation due to the assembly error when the moving body operates in the feed direction does not occur, and the driving force generated at each roller and the outer circumference of the drive shaft does not vary, so long stroke The stable feeding operation can be realized even by driving, the feeding control accuracy and the assemblability can be improved, and the device can be inexpensive because it can be configured with a simple guide mechanism. According to a tenth aspect of the present invention, the output means includes a plurality of D / A converters that convert a digital signal from the CPU into an analog signal in order to independently apply a press setting signal to the plurality of piezoelectric elements, and a plurality of the third and third converters. Deformation amount measuring means, a pressure setting signal which is an output signal of the plurality of D / A converters, and a current pressing amount which is an output signal of the plurality of third deformation amount measuring means are compared to perform servo control. And 5 servo control means. According to this invention, the preload fluctuation due to the assembly error when the moving body operates in the feeding direction does not occur, and the driving force generated at each roller and the outer circumference of the driving shaft does not vary, so that the long stroke A stable feeding operation can be realized even by driving, feeding control accuracy and assemblability can be improved, and a simple guide mechanism can be configured, so that the apparatus becomes inexpensive. According to an eleventh aspect of the present invention, when the driven shaft has a distance between the pressing point of the first pressing means and the rotation support point is L1, and a distance between the pressing point of the first pressing means and the roller is L2, L is L.
It is characterized in that the third deformation amount measuring means displacement magnifying mechanism satisfying the condition of 2> L1 is formed. According to this invention, since the driven shaft can obtain a large pressing stroke even if the amount of expansion and contraction of the piezoelectric element used for the first pressing means is small, the mechanism arranged around the drive shaft can be made small and the device can be miniaturized. Can be achieved.

【００１２】[0012]

【発明の実施の形態】以下、本発明を図に示した実施形
態を用いて詳細に説明する。但し、この実施形態に記載
される構成要素、種類、組み合わせ、形状、その相対配
置などは特定的な記載がない限り、この発明の範囲をそ
れのみに限定する主旨ではなく単なる説明例に過ぎな
い。図１は、本発明の第１の実施形態に係る摩擦駆動装
置の制御系構成図である。図１（ａ）は、摩擦駆動装置
の上面図であり、（ｂ）はその右側面図であり、（ｃ）
は部分断面図である。この摩擦駆動装置は、例えば光デ
ィスク用原盤露光装置に用いる送り装置に使用される。
図示しない除振機構、例えば、空気圧によるサーボマウ
ンタ上に設けたベース９０上には、送り方向と直交する
方向に離間配置されて基端部をベース９０に固定した支
柱８９（８９ａ、８９ｂ）が立設されており、各支柱８
９の上端部には、例えば球体、円筒ローラ等を送り方向
に配置したころがり軸受１４（１４ａ、１４ｂ）、案内
機構を介して移動体１３が送り方向へ移動可能に支持さ
れている。移動体１３には、上部に加工対象物としての
光ディスク原盤を支持するターンテーブル１８を固定
し、図示しない外部より供給される圧縮空気によりラジ
アル、スラスト方向に静圧浮上するエアスピンドル１９
が内部に配置されており、エアスピンドル１９には回転
駆動モータ２０を介して、その出力が一周３６０度を数
千に等分割されたＡ相、Ｂ相パルスと、一周に１回発生
するＺ相パルスとから構成される光学式ロータリエンコ
ーダ（１）２１が固定されており、図示しない外部から
の回転駆動モータ２０への通電信号により回転自在に構
成されている。また、移動体１３の送り方向より見て左
側端部の下部には、例えば、送り方向における所定の分
解能を提供するＡ相、Ｂ相パルスから構成される光学式
リニアエンコーダ等の送り方向の位置を計測する受光部
１５ａと、スケール１５ｂとから構成される位置検出手
段１５が設けられている。スケール１５ｂは取付板
（１）１５ｃを介して移動体１３に固定されており、受
光部１５ａは取付板（２）１７を介してベース９０側に
固定されている。図１では、スケール１５ｂが移動体１
３に固定され、受光部１５ａがベース９０に固定されて
いるが、受光部１５ａを移動体１３に固定し、スケール
１５ｂをベース９０に固定する構成としても構わない。
さらに移動体１３から送り方向へ突出する突出部１３ａ
の下部には、横方向へ延びる駆動軸１を支持する第１の
固定板２２及び第２の固定板２３の上端部が夫々固定的
に支持されている。さらに駆動軸１の外周にころがり接
触するローラ８を、例えばアンギュラ軸受等を対向した
ころがり軸受２９を介して同心状に設けた従動軸７が駆
動軸１の軸線に対して円周方向に配置されている。BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the embodiments shown in the drawings. However, the constituent elements, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely explanatory examples, not the gist of limiting the scope of the present invention thereto, unless specifically stated. . FIG. 1 is a control system configuration diagram of a friction drive device according to a first embodiment of the present invention. 1A is a top view of the friction drive device, FIG. 1B is a right side view thereof, and FIG.
FIG. 4 is a partial cross-sectional view. This friction drive device is used, for example, in a feeding device used in an optical disk master exposure device.
On a vibration isolation mechanism (not shown), for example, on a base 90 provided on a servo mounter using air pressure, columns 89 (89a, 89b) that are spaced apart in the direction orthogonal to the feed direction and whose base ends are fixed to the base 90 are provided. It is erected and each pillar 8
At the upper end of 9, a rolling bearing 14 (14a, 14b) in which, for example, a sphere, a cylindrical roller, etc. are arranged in the feed direction, and a moving body 13 are supported movably in the feed direction via a guide mechanism. A turntable 18 for supporting an optical disk master as an object to be machined is fixed to the upper part of the moving body 13, and an air spindle 19 which floats by static pressure in the radial and thrust directions by compressed air supplied from the outside (not shown).
Is arranged inside the air spindle 19 through the rotary drive motor 20. The output of the A phase and B phase pulses is obtained by equally dividing a 360 ° round into several thousand, and the Z pulse generated once per round. An optical rotary encoder (1) 21 composed of a phase pulse is fixed, and is configured to be rotatable by an energization signal from a not-shown external rotation drive motor 20. Further, in the lower part of the left end of the moving body 13 when viewed from the feed direction, for example, a position in the feed direction such as an optical linear encoder including A-phase and B-phase pulses that provides a predetermined resolution in the feed direction. A position detecting unit 15 including a light receiving unit 15a that measures the position and a scale 15b is provided. The scale 15b is fixed to the moving body 13 via the mounting plate (1) 15c, and the light receiving portion 15a is fixed to the base 90 side via the mounting plate (2) 17. In FIG. 1, the scale 15b is the moving body 1.
However, the light receiving unit 15a may be fixed to the moving body 13 and the scale 15b may be fixed to the base 90.
Further, a protruding portion 13a protruding from the moving body 13 in the feeding direction.
Upper ends of a first fixing plate 22 and a second fixing plate 23 that support the drive shaft 1 extending in the lateral direction are fixedly supported on the lower part of the. Further, a driven shaft 7 provided concentrically with a roller 8 in rolling contact with the outer periphery of the drive shaft 1 via a rolling bearing 29 facing an angular bearing or the like is arranged in the circumferential direction with respect to the axis of the drive shaft 1. ing.

【００１３】図２（ａ）は図１のＡ−Ａ’断面を表し、
（ｂ）はＢ−Ｂ’断面を表す。従動軸７の右側端部は、
図１（ｂ）の断面図に示すように、第２の固定板２３の
凹部に従動軸７に設けたローラ８を駆動軸１の外周に押
圧し、従動軸７を駆動軸１の外周接線方向に押圧するよ
うに例えば、ベローズバネ等を圧縮変形させた第１の弾
性体、第２の弾性体３５、３８等が設けられおり、従動
軸７の右側端部を自由支持する構成となっている。第１
の固定板２２の右側面には、図１（ｃ）の断面図に示す
ように、従動軸７の左側端部外周とその内周が嵌合す
る、例えば球面軸受等の軸受２６が固定されており、従
動軸７はその軸受２６の回動支持点２４を含む平面内に
回動可能な構成となっている。さらに、第１の固定板２
２の凹部には、回動支持点２４を挟んでローラ８と反対
側に、駆動軸１の外周の接線方向で第２の弾性体３８の
反力による回動支持点２４周りのモーメント力を相殺す
る方向に従動軸７を押圧する図２（ａ）に示すような第
２の圧電素子３１が伸縮方向に固定されており、全体で
図１（ｃ）の角度調整手段５１を構成している。ここ
で、駆動軸１と従動軸７の設定位置は、第２の圧電素子
３１の伸縮ストロークの１／２位置で駆動軸１と従動軸
７の軸芯が略平行位置となるように設けられている。以
上の構成により、第２の圧電素子３１の図示しないリー
ド線端末より電圧を印加すれば、駆動軸１と従動軸７の
軸芯が平行となる位置を略０度として駆動軸１と従動軸
７の交差角度を正負に自在に調整することができる。さ
らに駆動軸１の右側端部は第一の段付になっており、そ
の外周はベース９０に固定され上部に段付の貫通穴を設
けたハウジング１０の左側円筒穴部に同心状にその外輪
を固定されたアンギュラ軸受等の対向するころがり軸受
（３）２の内周部に嵌合しており、駆動軸１に設けたネ
ジ部ところがり軸受（３）２の内周部が軸受止め３にて
固定されている。さらに、駆動軸１の第二の段付部外周
はハウジング１０の右側円筒穴部に同心状に固定され、
一般的にその出力が一周を数千等分割したＡ相、Ｂ相パ
ルスと、一周に１回発生するＺ相パルスから構成される
ロータリエンコーダ（２）６を固定した送り駆動モータ
５の駆動軸とが、オルダム式等のカップリング４により
連結されている。さらに、駆動軸１の左側端部は、段付
部の外周がベース９０に固定され上部に貫通穴が設けら
れ、その貫通穴と同心状に例えば、深溝玉軸受等のころ
がり軸受（４）１２の外輪が軸心方向に移動可能となる
ように固定されたころがり軸受（４）１２の内輪に嵌合
する構成となっている。FIG. 2A shows a cross section taken along the line AA 'of FIG.
(B) represents a BB 'cross section. The right end of the driven shaft 7 is
As shown in the cross-sectional view of FIG. 1B, the roller 8 provided on the driven shaft 7 of the recess of the second fixing plate 23 is pressed against the outer circumference of the drive shaft 1, and the driven shaft 7 is tangential to the outer circumference of the drive shaft 1. For example, a first elastic body and a second elastic body 35, 38 obtained by compressing and deforming a bellows spring or the like are provided so as to be pressed in a direction, and the right end portion of the driven shaft 7 is freely supported. There is. First
As shown in the sectional view of FIG. 1C, a bearing 26, such as a spherical bearing, is fixed to the right side surface of the stationary plate 22. The outer periphery of the left end portion of the driven shaft 7 and the inner periphery thereof are fitted to each other. Therefore, the driven shaft 7 is configured to be rotatable within a plane including the rotation support point 24 of the bearing 26 thereof. Furthermore, the first fixing plate 2
A moment force around the rotation support point 24 due to the reaction force of the second elastic body 38 in the tangential direction of the outer periphery of the drive shaft 1 is provided in the concave portion 2 on the side opposite to the roller 8 with the rotation support point 24 interposed therebetween. A second piezoelectric element 31 as shown in FIG. 2 (a) for pressing the driven shaft 7 in the canceling direction is fixed in the expansion / contraction direction, and constitutes the angle adjusting means 51 of FIG. 1 (c) as a whole. There is. Here, the set positions of the drive shaft 1 and the driven shaft 7 are set so that the axes of the drive shaft 1 and the driven shaft 7 are substantially parallel to each other at a half position of the expansion / contraction stroke of the second piezoelectric element 31. ing. With the above configuration, when a voltage is applied from the lead wire end (not shown) of the second piezoelectric element 31, the position where the axes of the drive shaft 1 and the driven shaft 7 are parallel to each other is set to approximately 0 degree, and the drive shaft 1 and the driven shaft are set. The intersection angle of 7 can be freely adjusted to be positive or negative. Further, the right end of the drive shaft 1 has a first step, and the outer periphery of the outer ring is fixed concentrically to the left cylindrical hole of the housing 10 fixed to the base 90 and provided with a stepped through hole in the upper part. Is fitted to the inner peripheral portion of the opposed rolling bearing (3) 2 such as a fixed angular bearing, and the inner peripheral portion of the threaded roller bearing (3) 2 provided on the drive shaft 1 is a bearing stopper 3 It is fixed in. Further, the outer periphery of the second stepped portion of the drive shaft 1 is concentrically fixed to the right cylindrical hole portion of the housing 10,
In general, the drive shaft of the feed drive motor 5 having a fixed rotary encoder (2) 6 whose output is composed of A-phase and B-phase pulses obtained by dividing the circuit into several thousand equal parts and a Z-phase pulse generated once per circuit. And are connected by a coupling 4 of Oldham type or the like. Further, at the left end of the drive shaft 1, the outer periphery of the stepped portion is fixed to the base 90 and a through hole is provided in the upper portion, and concentrically with the through hole, for example, a rolling bearing (4) 12 such as a deep groove ball bearing. The outer ring is fitted in the inner ring of the rolling bearing (4) 12 fixed so as to be movable in the axial direction.

【００１４】図３は、本発明の摩擦駆動装置の制御系の
構成図である。図示しないＰＣからなる全体制御装置か
ら位置指令パルス信号１０９及び方向指定信号１１０が
アップ／ダウンカウンタ（１）１１１に夫々接続され、
その出力信号は減算器１１３の一方に接続され、他方は
位置検出手段１５のパルス出力信号１２１から方向判別
信号１２２を検出する方向判別器１１９を介してアップ
／ダウンカウンタ（２）１１２の出力信号が減算器１１
３に接続され、その減算結果はＤ／Ａ変換器１１４によ
り電圧信号に変換されて速度指令信号１００が出力され
る。その速度指令信号１００は、差動増幅器１１５の一
方に入力され、他方は位置検出手段１５のパルス出力信
号１２１から移動体１３の現在速度を検出するＦ／Ｖ変
換器（２）１１８の出力信号である現在速度信号１０１
が入力されて加減算される。そして、速度偏差となるそ
の出力信号は、微積分回路あるいは、位相の進み、遅れ
回路等で構成された第１の位相補償器１１６に入力さ
れ、電力増幅器１１７を介して送り駆動モータ５に接続
されており、このようにＤ／Ａ変換器１１４の出力信号
以降の構成にて第１の速度サーボ制御手段１２３を構成
している。さらに、速度指令信号１００と現在速度信号
１０１は、第２の差動増幅器１０２に接続されて速度偏
差信号１２８を出力する。速度偏差信号１２８は、角度
調整手段５１の位相遅れ量等を補償する第２の位相補償
器１０３に接続され、その出力信号は、速度サーボ系の
利得を調整するゲイン調整器１０４に入力され、その出
力が図示しない全体制御装置からのＯＮ／ＯＦＦ信号１
２６により操作可能なスイッチ（１）１０６を介して定
電圧発生手段１２５の出力と駆動アンプ１０５にて加算
され、その出力が第２の圧電素子３１に接続されてお
り、第２の速度サーボ制御手段１０８を構成している。FIG. 3 is a block diagram of the control system of the friction drive device of the present invention. A position control pulse signal 109 and a direction designating signal 110 are respectively connected to an up / down counter (1) 111 from an overall control device including a PC (not shown),
The output signal is connected to one side of the subtractor 113, and the other side is output signal of the up / down counter (2) 112 via the direction discriminator 119 which detects the direction discrimination signal 122 from the pulse output signal 121 of the position detecting means 15. Is the subtractor 11
3 and the subtraction result is converted into a voltage signal by the D / A converter 114 and the speed command signal 100 is output. The speed command signal 100 is input to one of the differential amplifiers 115, and the other is an output signal of an F / V converter (2) 118 that detects the current speed of the moving body 13 from the pulse output signal 121 of the position detecting means 15. Present speed signal 101
Is input and added or subtracted. Then, the output signal which becomes the speed deviation is input to the first phase compensator 116 composed of a fine integration circuit or a phase advance / delay circuit or the like, and is connected to the feed drive motor 5 via the power amplifier 117. As described above, the first speed servo control means 123 is configured by the configuration after the output signal of the D / A converter 114. Further, the speed command signal 100 and the current speed signal 101 are connected to the second differential amplifier 102 to output a speed deviation signal 128. The speed deviation signal 128 is connected to the second phase compensator 103 for compensating for the phase delay amount of the angle adjusting means 51, and the output signal thereof is input to the gain adjuster 104 for adjusting the gain of the speed servo system, The output is an ON / OFF signal 1 from the overall control device (not shown).
The output of the constant voltage generating means 125 is added to the output of the drive amplifier 105 via the switch (1) 106 operable by the switch 26, and the output is connected to the second piezoelectric element 31 for the second speed servo control. It constitutes means 108.

【００１５】ここで、構成される速度伝達関数について
図４を用いて説明する。図４は、縦軸がゲイン（ｄＢ）
横軸が対数目盛で周波数（Ｈｚ）を表している。送り駆
動モータ５の回転速度を制御する第１の速度サーボ制御
手段１２３の開ループ伝達関数は、図４のに示すよう
な直線的な傾き−２０ｄＢ／ｄｅｃのゲイン曲線とな
る。また第１の速度サーボ制御手段１２３は、微積分回
路あるいは位相進み、遅れ回路等で構成した第１の位相
補償器１１６によって、サーボ系が発振しないように位
相余裕（４０度以上）、ゲイン余裕（１５ｄＢ以上）が
確保される構成とする。また、第１の速度サーボ制御手
段１２３の閉ループ特性は、図４のに示すようなゲイ
ン曲線となり、サーボ帯域ｆ１まで低域の速度変動に対
して追従可能とする。また、第２の速度サーボ制御手段
１０８では、図４ので示すように、その遮断周波数ｆ
ｃが速度サーボ制御手段１２３のサーボ帯域ｆ１に対し
てｆｃ≧ｆ１となるハイパスフィルター要素を持つ第２
の位相補償器１０３にて構成している。また、第２の速
度サーボ制御手段１０８の開ループ伝達関数のゲイン曲
線は図４のに示すように低域の速度変動に対してはゲ
インが低いので追従しないが、数１０Ｈｚ帯域では、高
い開ループゲインを持つように構成しているので、高域
の速度変動に対して追従可能である。以上の速度伝達関
数をもつことにより、低域から、ターンテーブル１８上
に載置されるガラス基板等の偏芯による回転振動等の数
１０Ｈｚ帯域の外乱振動があっても安定して速度制御が
可能となる。Here, the constructed velocity transfer function will be described with reference to FIG. In FIG. 4, the vertical axis represents the gain (dB).
The horizontal axis represents the frequency (Hz) on a logarithmic scale. The open loop transfer function of the first speed servo control means 123 for controlling the rotation speed of the feed drive motor 5 becomes a gain curve having a linear slope of -20 dB / dec as shown in FIG. Further, the first speed servo control means 123 uses a first phase compensator 116 composed of a fine integration circuit or a phase advance / delay circuit or the like so as to prevent the servo system from oscillating. 15 dB or more) is ensured. Further, the closed-loop characteristic of the first speed servo control means 123 has a gain curve as shown in FIG. 4, and can follow the speed fluctuation in the low range up to the servo band f 1 . Further, in the second speed servo control means 108, as shown by in FIG.
The second c has a high-pass filter element such that fc ≧ f 1 with respect to the servo band f 1 of the speed servo control means 123.
The phase compensator 103 of FIG. Further, the gain curve of the open loop transfer function of the second speed servo control means 108 does not follow the low speed speed fluctuation because the gain is low as shown in FIG. 4, but it is high in the several tens Hz band. Since it is configured to have a loop gain, it can follow speed fluctuations in the high frequency range. By having the above velocity transfer function, the velocity control can be stably performed even if there is a disturbance vibration of several tens Hz band such as a rotational vibration due to the eccentricity of the glass substrate mounted on the turntable 18 from the low frequency range. It will be possible.

【００１６】図５は、本発明の図３内の定電圧発生手段
１２５の構成図であり、図５は、定電圧発生手段１２５
の角度補正電圧算出の動作フローチャートである。定電
圧発生手段１２５は、プログラムにより制御するＣＰＵ
５８と、その動作プログラムが記憶されたＲＯＭ６０
と、データの書き込み／読み出しを行うワークメモリと
してのＲＡＭ６１と、ＣＰＵ５８の指令により位置検出
手段１５のパルス出力信号１２１と駆動軸１の回転角度
位置を検出する角度検出手段６（ロータリエンコーダ
（２））の１回転当たりの原点検出信号４９から、従動
軸７の駆動軸１に対する現在傾き角度を算出する演算部
（１）１３２（図６のステップＳ７）と、現在傾き角度
の算出結果から従動軸７の駆動軸１に対する傾き角度が
ゼロとなるように補正電圧を演算する補正演算部１３３
（図６のステップＳ８）と、その補正演算出力をアナロ
グ信号に変換する第２のＤ／Ａ変換器１２９にて構成し
ている。尚、演算部（１）１３２と補正演算部１３３は
ＣＰＵ５８によるプログラムにより構成される。FIG. 5 is a block diagram of the constant voltage generating means 125 in FIG. 3 of the present invention, and FIG. 5 shows the constant voltage generating means 125.
5 is an operation flowchart of the angle correction voltage calculation of FIG. The constant voltage generating means 125 is a CPU controlled by a program
58 and a ROM 60 storing the operation program
And a RAM 61 as a work memory for writing / reading data, a pulse output signal 121 of the position detecting means 15 and an angle detecting means 6 (rotary encoder (2) for detecting the rotational angular position of the drive shaft 1 according to a command from the CPU 58). ) Calculation unit (1) 132 (step S7 in FIG. 6) for calculating the current tilt angle of the driven shaft 7 with respect to the drive shaft 1 from the origin detection signal 49 per rotation, and the driven shaft is calculated based on the calculation result of the current tilt angle. Correction calculator 133 that calculates a correction voltage so that the tilt angle of drive shaft 7 with respect to drive axis 1 becomes zero.
(Step S8 in FIG. 6) and a second D / A converter 129 for converting the corrected calculation output into an analog signal. The calculation unit (1) 132 and the correction calculation unit 133 are configured by a program by the CPU 58.

【００１７】以上の構成による速度制御原理について説
明する。図７は移動体１３の駆動原理を説明するための
交差角度の詳細を示す図である。図２（ａ）により、図
示しない第２の圧電素子３１の端末リード線より適当な
通電電圧を第２の圧電素子３１に印加すると、図７の点
線に示すように駆動軸１の軸心１ａと従動軸７の軸心７
ａは、ある角度θで交差した状態でローラ８の外周と駆
動軸１の外周がころがり接触する。この状態で、図示し
ない送り駆動モータ５の端末より通電すれば、ローラ８
の外周と駆動軸１の外周の接触点は螺旋状に移動し、移
動体１３が送り方向に移動自在となる。この時、従動軸
７自身は回転せず、ころがり軸受（２）９の外輪が回転
する外輪回転である。このとき駆動軸１が１回転当たり
に移動体１３を移動する移動量Ｌリード量は、駆動軸１
の外形寸法をＤとすれば、 Ｌ＝π・Ｄ・ｓｉｎθ ―――――――――― θ＝ｓｉｎ−１｛Ｌ／π・Ｄ｝―――――――― で表され、例えば、Ｄ＝３０ｍｍ条件での交差角度とリ
ード量Ｌの関係は図１４の両対数グラフで表される。従
って、駆動軸１の回転数をＮｒｐｍとすれば、送り速度
υは、 υ＝Ｌ・Ｎ／６０＝π・Ｄ・ｓｉｎθ・Ｎ／６０ ―――――――― で表され、リードが小さい場合、言い換えると、交差角
度が小さい場合は、ｓｉｎθ≒θとなるから式は、 υ＝π・Ｄ・θ・Ｎ／６０ ―――――――― で表される。本発明では、式の送り速度υを駆動軸１
の回転数Ｎを任意の一定速度に固定し、角度調整手段５
１にてθを制御量として送り速度υを制御し、移動体１
３の前進／後退は、θを正負にすることによって行う。
従って、駆動軸１の回転方向としては、ＣＷ／ＣＣＷの
どちらか一方で十分である。先に説明した構成によれ
ば、駆動軸１が常に回転している状態にて移動体１３を
移動／停止できるので、静止摩擦やすべり摩擦を発生せ
ず、速度に比例するころがり摩擦に対する補償だけで良
好な送り精度が得られる。The speed control principle with the above configuration will be described. FIG. 7 is a diagram showing details of the intersection angle for explaining the driving principle of the moving body 13. As shown in FIG. 2A, when an appropriate energization voltage is applied to the second piezoelectric element 31 from the terminal lead wire of the second piezoelectric element 31 not shown, as shown by the dotted line in FIG. And the axis 7 of the driven shaft 7
In a, the outer circumference of the roller 8 and the outer circumference of the drive shaft 1 make rolling contact with each other in a state of intersecting at a certain angle θ. In this state, if power is supplied from the end of the feed drive motor 5 (not shown), the roller 8
The contact point between the outer periphery of the drive shaft 1 and the outer periphery of the drive shaft 1 moves spirally, and the moving body 13 becomes movable in the feed direction. At this time, the driven shaft 7 itself does not rotate, and the outer ring of the rolling bearing (2) 9 rotates to rotate the outer ring. At this time, the moving amount L lead amount by which the drive shaft 1 moves the moving body 13 per rotation is the drive shaft 1
Let D be the outer dimension of L = π ・ D ・ sin θ ―――――――――― θ = sin −1 {L / π ・ D} ―――――――― For example, the relationship between the crossing angle and the lead amount L under the condition of D = 30 mm is represented by the double logarithmic graph of FIG. Therefore, if the number of rotations of the drive shaft 1 is N rpm, the feed rate υ is represented by υ = L · N / 60 = π · D · sin θ · N / 60 ―――――――― When it is small, in other words, when the crossing angle is small, sin θ≈θ, so the formula is expressed by υ = π · D · θ · N / 60 ――――――――. In the present invention, the feed rate υ of the formula is set to the drive shaft 1
The rotation speed N of is fixed to an arbitrary constant speed, and the angle adjusting means 5
1 controls the feed rate υ with θ as a controlled variable, and the moving body 1
The forward / backward movement of 3 is performed by making θ positive or negative.
Therefore, either the CW / CCW is sufficient as the rotation direction of the drive shaft 1. According to the configuration described above, the moving body 13 can be moved / stopped while the drive shaft 1 is constantly rotating, so that static friction and sliding friction are not generated, and only compensation for rolling friction proportional to speed is performed. Good feed accuracy can be obtained.

【００１８】以上、前記で述べた説明では、図１（ｃ）
の角度調整手段５１を図２（ａ）の第１の固定板２２の
凹部に駆動軸１外周の接線方向で第２の弾性体３８の反
力による回動支持点２４周りのモーメント力を相殺する
方向に、従動軸７を押圧する第２の圧電素子３１が伸縮
方向に固定した構成としていた。そのときの第２の圧電
素子３１の印加電圧に対する変位量の関係は、図８に示
すように非線形であり、この特性の場合第２の速度サー
ボ制御手段１０８が発振等を発生する虞がある。そこ
で、その発振を防止する構成を図９、１０に示す。図９
は第２の押圧板の断面構成図であり、図１０は第２のサ
ーボ制御手段のブロック図である。前述と重複する部分
の説明は省略する。図９の第１の固定板２２の凹部に第
２の圧電素子３１を伸縮方向に固定し、第２の変形部３
２ａに抵抗値の変化によってその変形量を検出する歪み
ゲージ等で構成された第２の変形量測定手段３４を設け
た第２の押圧板３２にて第２の押圧手段４８を構成して
いる。この構成で図１０に示すような第２の圧電素子３
１の変位量を、第２の変形量測定手段３４により帰還す
る構成とした第２のサーボ制御手段７７を設けている。
図３で説明した駆動アンプ１０５をこの第２のサーボ制
御手段７７に置き換えれば、第２の圧電素子３１の非線
形特性を回避することができる。さらに、前述の図９、
１０の説明では、従動軸７に設けたローラ８の押圧とし
て第１の弾性体３５による反力のみの構成としていた
が、この場合、経年変化等で駆動軸１が磨耗すると押圧
力が変化してしまい、簡単に押圧力を変更できないので
部品交換をする必要が生じてしまい保守上好ましくな
い。これを回避する構成として図１１に示すように、前
記の構成に加えて第１の固定板２２の凹部には、駆動軸
１の軸線と直角方向で第１の弾性体３５の押圧力による
回動支持点２４周りのモーメント力を相殺する方向に、
従動軸７を押圧する第１の圧電素子２７を伸縮方向に固
定し、さらに従動軸７を押圧する側の固定端に第１の変
形部２８を設けた第１の押圧板２８からなる第１の押圧
手段４７を設けた構成としている。また、図１１（ｃ）
に示すように、第１の押圧板２８の第１の変形部２８ａ
に例えば、抵抗値の変化によってその変形量を検出する
歪みゲージ等の第１の変形量測定手段３０を設け、その
第１の変形量測定手段３０の出力信号と定電圧回路設定
電圧を比較してサーボ制御する構成としている。As described above, in the above description, FIG.
2A, the moment force around the rotation support point 24 due to the reaction force of the second elastic body 38 in the tangential direction of the outer periphery of the drive shaft 1 is offset in the recess of the first fixing plate 22 of FIG. The second piezoelectric element 31 that presses the driven shaft 7 is fixed in the expanding and contracting direction. The relationship between the amount of displacement and the applied voltage of the second piezoelectric element 31 at that time is non-linear as shown in FIG. 8, and in the case of this characteristic, the second speed servo control means 108 may cause oscillation or the like. . Therefore, a configuration for preventing the oscillation is shown in FIGS. Figure 9
Is a sectional configuration diagram of the second pressing plate, and FIG. 10 is a block diagram of the second servo control means. The description of the same parts as those described above will be omitted. The second piezoelectric element 31 is fixed in the expansion / contraction direction in the concave portion of the first fixing plate 22 of FIG.
The second pressing means 48 is constituted by the second pressing plate 32 provided with the second deformation amount measuring means 34 composed of a strain gauge or the like for detecting the amount of deformation of the 2a by the change of the resistance value. . With this structure, the second piezoelectric element 3 as shown in FIG.
A second servo control means 77 is provided which is configured to feed back the displacement amount of 1 by the second deformation amount measuring means 34.
By replacing the drive amplifier 105 described with reference to FIG. 3 with the second servo control means 77, the non-linear characteristic of the second piezoelectric element 31 can be avoided. Further, as shown in FIG.
In the description of No. 10, the roller 8 provided on the driven shaft 7 is pressed only by the reaction force by the first elastic body 35, but in this case, when the drive shaft 1 is worn due to aging or the like, the pressing force changes. Since the pressing force cannot be easily changed, it becomes necessary to replace the parts, which is not preferable for maintenance. As a structure for avoiding this, as shown in FIG. 11, in addition to the structure described above, the concave portion of the first fixing plate 22 is rotated by the pressing force of the first elastic body 35 in the direction perpendicular to the axis of the drive shaft 1. In the direction to cancel the moment force around the dynamic support point 24,
A first pressing plate 28 having a first piezoelectric element 27 that presses the driven shaft 7 fixed in the expansion / contraction direction, and a first deformable portion 28 provided at the fixed end on the side that presses the driven shaft 7 The pressing means 47 is provided. Also, FIG. 11 (c)
As shown in, the first deformable portion 28a of the first pressing plate 28
In addition, for example, a first deformation amount measuring means 30 such as a strain gauge for detecting the deformation amount by the change of the resistance value is provided, and the output signal of the first deformation amount measuring means 30 and the constant voltage circuit set voltage are compared. Servo control.

【００１９】図１２は第１のサーボ制御手段のブロック
図である。定電圧回路５５の出力信号は、駆動信号が図
示しないＣＰＵに接続され、ＯＮ時に定電圧回路５５の
出力信号に接続し、ＯＦＦ時に回路の０Ｖ（ＧＮＤ）に
接続するスイッチ（４）６８ａを介して信号７４ａが差
動アンプ６９ａの一方の入力に接続されており、また、
第１の変形量測定手段３０の出力信号は、抵抗値変化を
検出するブリッジ回路７３ａに接続され、その出力信号
は微少信号を増幅する増幅器７２ａにより増幅されて信
号７５ａが差動アンプ６９ａの他方の入力に接続され、
定電圧回路５５の出力信号及び０Ｖ（ＧＮＤ）信号と引
き算され、その出力信号は補償回路７０ａ、ゲイン調整
器７１ａを介して駆動アンプ５７ａに入力されている。
このようにスイッチ６８ａ以降から駆動アンプ５７ａま
でが第１のサーボ制御手段７６を構成しており、その出
力信号は第１の圧電素子２７に接続されている。ここ
で、図１２の駆動アンプ５７ａへの入力信号に対する図
１１の第１の押圧手段４７の変位量の間の周波数特性
は、図１３に示すように２次系Ａであり、補償回路７０
ａを調整することにより、一般的なサーボ系の安定指標
値である位相余裕４０度以上とゲイン余裕１５ｄＢ以上
に設けている。この構成では、適当な定電圧回路５５か
らの出力により瞬時に押圧力を回復することができる。
さらに、駆動軸１と案内機構（１４ａ、１４ｂ）の組立
の通り誤差等により押圧力がストローク内で変動し、す
べりを発生することがある。これを回避する構成を図１
５、１６に示す。図１５は第３の変形量測定手段の構成
図であり、図１６は第４のサーボ制御手段のブロック図
である。図１６の第４のサーボ制御手段８６は、第１の
圧電素子２７への押圧設定信号を与えるＤ／Ａ変換器８
４と、第１の押圧板２８と、回動支持点２４とローラ８
間にあって、従動軸７の外周部に従動軸７の押圧方向の
変形量を検出する第３の変形量測定手段４６と、Ｄ／Ａ
変換器８４の出力信号８５（押圧設定信号）と第３の変
形量測定手段４６の出力信号８０（現在押圧量）とを差
動アンプ６９で比較してサーボ制御する第４のサーボ制
御手段８６から構成されている。この構成では、例え
ば、従動軸７の押圧量と変形量の関係を予めデータから
把握しておき、押圧設定信号８５をＤ／Ａ変換器８４よ
り出力することで行う。FIG. 12 is a block diagram of the first servo control means. The output signal of the constant voltage circuit 55 is connected to a CPU (not shown) whose drive signal is not shown. The output signal of the constant voltage circuit 55 is connected to the output signal of the constant voltage circuit 55 when turned on, and is connected to 0V (GND) of the circuit when turned off via a switch (4) 68a. Signal 74a is connected to one input of the differential amplifier 69a, and
The output signal of the first deformation amount measuring means 30 is connected to a bridge circuit 73a that detects a change in resistance value, and the output signal is amplified by an amplifier 72a that amplifies a minute signal so that the signal 75a is the other of the differential amplifier 69a. Connected to the input of
The output signal of the constant voltage circuit 55 and the 0V (GND) signal are subtracted, and the output signal is input to the drive amplifier 57a via the compensation circuit 70a and the gain adjuster 71a.
In this way, the switches 68a to the drive amplifier 57a constitute the first servo control means 76, and the output signal thereof is connected to the first piezoelectric element 27. Here, the frequency characteristic between the displacement amount of the first pressing means 47 of FIG. 11 with respect to the input signal to the drive amplifier 57a of FIG. 12 is the secondary system A as shown in FIG.
By adjusting a, the phase margin of 40 degrees or more and the gain margin of 15 dB or more, which are general stability index values of the servo system, are provided. With this configuration, the pressing force can be instantly restored by the output from the appropriate constant voltage circuit 55.
Further, due to an error in assembling the drive shaft 1 and the guide mechanism (14a, 14b), the pressing force may fluctuate within the stroke, causing slippage. A configuration for avoiding this is shown in FIG.
5 and 16 are shown. FIG. 15 is a block diagram of the third deformation amount measuring means, and FIG. 16 is a block diagram of the fourth servo control means. The fourth servo control means 86 of FIG. 16 provides the D / A converter 8 which gives a pressure setting signal to the first piezoelectric element 27.
4, the first pressing plate 28, the rotation support point 24, and the roller 8
A third deformation amount measuring means 46 for detecting the deformation amount of the driven shaft 7 in the pressing direction, which is provided in the outer peripheral portion of the driven shaft 7, and D / A.
The fourth servo control means 86 for servo-controlling the output signal 85 (press setting signal) of the converter 84 and the output signal 80 (current pressing quantity) of the third deformation amount measuring means 46 by the differential amplifier 69. It consists of In this configuration, for example, the relationship between the pressing amount and the deformation amount of the driven shaft 7 is grasped in advance from the data, and the pressing setting signal 85 is output from the D / A converter 84.

【００２０】以上までの説明では、１本の従動軸７での
構成を説明したが、複数の従動軸（７ａ、７ｂ、７ｃ）
での構成を図１８、１９に示す。図１８複数の従動軸
（この例では３本）の構成図である。（ａ）、（ｂ）は
異なる面で切断した断面図である。図１８（ｂ）の断面
図に示すように、第２の固定板２３に周方向に所定のピ
ッチにて設けた各凹部２３Ａ、２３Ｂ、２３Ｃ内に、夫
々、駆動軸１の軸線に対して円周方向に等角となるよう
に配置されて固定されている。更に、各従動軸７ａ〜７
ｃの外周に対して夫々回転自在に軸支されたローラ８ａ
〜８ｃを駆動軸１の外周から離間させる方向（離間方
向）に押圧する球３５ｄ〜３５ｆをコイルスプリング等
の３つの第１の弾性体３５ａ〜３５ｃ（押圧端部に配置
される）により押圧する構成を備えた第３の押圧板３６
ａ〜３６ｃと、各従動軸７ａ〜７ｃを駆動軸１の外周接
線方向に押圧する球３８ｄ〜３８ｆをコイルスプリング
等の３つの第２の弾性体３８ａ〜３８ｃ（押圧端部に配
置される）により押圧する構成を備えた第４の押圧板４
０ａ〜４０ｃと、が設けられている。このように、従動
軸７ａ〜７ｃの右側端部を、弾性付勢された各球により
自由支持する構成となっている。なお、本発明の実施形
態では、第２の固定板２３と分離された第３の押圧板３
６ａ〜３６ｃと第４の押圧板４０ａ〜４０ｃに夫々第１
の弾性体３５ａ〜３５ｃ、第２の弾性体３８ａ〜３８ｃ
を設けているが、第２の固定板２３に各弾性体を直接設
けてもかまわない。In the above description, the structure with one driven shaft 7 has been described, but a plurality of driven shafts (7a, 7b, 7c) are provided.
18 and 19 show the configuration in FIG. 18 is a configuration diagram of a plurality of driven shafts (three in this example). (A), (b) is sectional drawing cut | disconnected by a different surface. As shown in the cross-sectional view of FIG. 18B, the recesses 23A, 23B, and 23C are provided in the second fixing plate 23 at a predetermined pitch in the circumferential direction, respectively, with respect to the axis of the drive shaft 1. It is arranged and fixed so as to be equiangular in the circumferential direction. Furthermore, each driven shaft 7a-7
Roller 8a rotatably supported on the outer circumference of c
~ 8c are pressed by the three first elastic bodies 35a-35c (arranged at the pressing end portions) such as coil springs to press the balls 35d-35f that press in the direction of separating the drive shaft 1 from the outer periphery of the drive shaft 1 (separation direction). Third pressing plate 36 having a configuration
a-36c and three second elastic bodies 38a-38c such as coil springs (disposed at the pressing end portions) 38d-38f for pressing the driven shafts 7a-7c in the outer peripheral tangential direction of the drive shaft 1. Fourth pressing plate 4 having a configuration of pressing by
0a to 40c are provided. As described above, the right end portions of the driven shafts 7a to 7c are freely supported by the elastically biased balls. In the embodiment of the present invention, the third pressing plate 3 separated from the second fixing plate 23 is used.
6a to 36c and the fourth pressing plates 40a to 40c respectively have the first
Elastic bodies 35a to 35c and second elastic bodies 38a to 38c
However, each elastic body may be directly provided on the second fixing plate 23.

【００２１】また、第１の固定板２２の右側面には、図
１８（ａ）の断面図に示すように、従動軸７ａ〜７ｃの
左側端部外周とその内周が嵌合する球面軸受等の軸受２
６ａ〜２６ｃが、駆動軸１の軸線に対して円周方向に等
角配置されて固定されており、従動軸７ａ〜７ｃは、そ
の軸受２６ａ〜２６ｃの回動支持点２４ａ〜２４ｃを含
む平面内に回動可能な構成となっている。さらに、第１
の固定板２２の凹部２２Ａ、２２Ｂ、２２Ｃには、回動
支持点２４ａ〜２４ｃを挟んだ各ローラ８ａ〜８ｃとは
反対側に、第１の圧電素子２７ａ〜２７ｃを伸縮方向に
固定する。即ち、第１の押圧手段４７ａ〜４７ｃと第２
の押圧手段４８ａ〜４８ｃが、駆動軸１の軸線に対して
円周方向に等角配置されて固定されている。即ち、第１
の押圧手段４７ａ〜４７ｃは、駆動軸１の軸線と直角方
向で第１の弾性体３５ａ〜３５ｃの押圧力による回動支
持点２４ａ〜２４ｃ周りのモーメント力を相殺する方向
に、従動軸７ａ〜７ｃを押圧するための第１の圧電素子
２７ａ〜２７ｃを伸縮方向に固定し、従動軸７ａ〜７ｃ
を押圧する側の固定端に第１の変形部２８ｄ〜２８ｆを
設けた構成を備えている。また、第２の押圧手段４８ａ
〜４８ｃは、駆動軸１外周の接線方向で第２の弾性体３
８ａ〜３８ｃの押圧力による回動支持点２４ａ〜２４ｃ
周りのモーメント力を相殺する方向に従動軸７ａ〜７ｃ
を押圧する第２の圧電素子３１ａ〜３１ｃを伸縮方向に
固定し、従動軸７ａ〜７ｃを押圧する側の固定端に第２
の変形部３２ｄ〜３２ｆを設けた構成を備えている。こ
の構成によると前記で述べたのと同様の動作であり、ま
た前記で説明したように、従動軸（７ａ、７ｂ、７ｃ）
が複数配置された時の組立誤差等による各従動軸の交差
角にバラツキがあっても、各々の交差角度を個々に調整
してリード誤差を除去でき、すべりを抑圧することがで
きる。さらに、図１７に示すように従動軸７は、第１の
押圧手段４７の押圧点Ｐと回動支持点２４間距離をＬ
１、押圧点Ｐとローラ８間距離をＬ２とした時にＬ２＞
Ｌ１として変位拡大機構を構成している。この構成によ
れば、第１の押圧手段４７に用いる第１の圧電素子２７
の伸縮量が小さくても、ローラ８と駆動軸１とのころが
り接触端では大きな押圧ストロークが得られるので、駆
動軸回りに配置する機構を小さく構成できることは言う
までもない。Further, as shown in the sectional view of FIG. 18A, the right side surface of the first fixing plate 22 is a spherical bearing in which the outer circumferences of the left end portions of the driven shafts 7a to 7c and the inner circumference thereof are fitted. Bearing 2
6a to 26c are arranged equiangularly in the circumferential direction with respect to the axis of the drive shaft 1 and fixed, and the driven shafts 7a to 7c are planes including the rotation support points 24a to 24c of the bearings 26a to 26c. It is configured to be rotatable inside. Furthermore, the first
In the concave portions 22A, 22B, 22C of the fixing plate 22, the first piezoelectric elements 27a to 27c are fixed in the expansion and contraction direction on the side opposite to the rollers 8a to 8c sandwiching the rotation support points 24a to 24c. That is, the first pressing means 47a-47c and the second pressing means 47a-47c
The pressing means 48a to 48c are fixed and arranged equiangularly in the circumferential direction with respect to the axis of the drive shaft 1. That is, the first
The pressing means 47a to 47c of the driven shafts 7a to 47c in the direction perpendicular to the axis of the drive shaft 1 cancel the moment force around the rotation support points 24a to 24c due to the pressing force of the first elastic bodies 35a to 35c. The first piezoelectric elements 27a to 27c for pressing 7c are fixed in the expansion and contraction direction, and the driven shafts 7a to 7c are fixed.
It has a configuration in which the first deforming portions 28d to 28f are provided at the fixed end on the side that presses. Also, the second pressing means 48a
48c is the second elastic body 3 in the tangential direction of the outer periphery of the drive shaft 1.
Rotational support points 24a to 24c by pressing forces of 8a to 38c
Driven shafts 7a to 7c in a direction that cancels out the surrounding moment force
The second piezoelectric elements 31a to 31c that press the are fixed in the expansion and contraction direction, and the second end is fixed to the fixed end that presses the driven shafts 7a to 7c.
It has a configuration in which the deformation portions 32d to 32f are provided. According to this configuration, the operation is the same as that described above, and as described above, the driven shafts (7a, 7b, 7c)
Even if there are variations in the crossing angle of each driven shaft due to an assembly error or the like when a plurality of are arranged, the respective crossing angles can be individually adjusted to remove the lead error and suppress the slip. Further, as shown in FIG. 17, the driven shaft 7 has a distance L between the pressing point P of the first pressing means 47 and the rotation supporting point 24.
1. When the distance between the pressing point P and the roller 8 is L2, L2>
A displacement magnifying mechanism is configured as L1. According to this configuration, the first piezoelectric element 27 used for the first pressing means 47.
Even if the amount of expansion and contraction is small, a large pressing stroke can be obtained at the rolling contact end of the roller 8 and the drive shaft 1, so it goes without saying that the mechanism arranged around the drive shaft can be made small.

【００２２】[0022]

【発明の効果】以上記載のごとく請求項１の発明によれ
ば、駆動軸と従動軸の交差角度を調整する角度調整手段
と、速度指令信号と現在速度信号に基づいて送り駆動モ
ータの回転速度を制御する第１の速度サーボ制御手段
と、速度偏差信号に基づいて角度調整手段への印加電圧
を増減して移動体の送り速度を制御する第２の速度サー
ボ制御手段を備えたこのようなサーボ系を構成すること
により、数Ｈｚ程度の低域速度変動を送り駆動モータで
おこない、また数１０Ｈｚ程度の高域速度変動を従動軸
の駆動軸に対する傾き角度を調整して制御しているの
で、回転振動等の外乱振動に対しても安定した送り制御
が実現でき送り精度の向上が図れる。また請求項２で
は、第２の速度サーボ制御手段に、第１の速度サーボ制
御手段のサーボ帯域をｆ１としたときに、遮断周波数ｆ
ｃがｆｃ≧ｆ１なる関係の１次以上のハイパスフィルタ
要素にて構成される第２の位相補償器を備えることによ
り、数Ｈｚ程度の低域速度変動に対する第１の速度サー
ボ制御手段と第２の速度サーボ制御手段の動作干渉を回
避することができ、更に安定した送り制御が実現でき、
それにより送り精度の向上が図れる。また請求項３で
は、第２の速度サーボ制御手段は、速度偏差信号を出力
する第２の差動増幅器と、第２の位相補償器と、ゲイン
調整器と、第２の速度サーボ制御手段のＯＮ／ＯＦＦを
行う第１のスイッチと、操作電圧を印加する駆動アンプ
と、定電圧発生手段を備えているので、数１０μｍ〜数
ｍｍ程度の広いリードを実現でき、これにより高分解能
の送りが可能となり、狭トラックピッチでの送り精度の
向上が図れる。As described above, according to the invention of claim 1, the angle adjusting means for adjusting the intersection angle between the drive shaft and the driven shaft, and the rotation speed of the feed drive motor based on the speed command signal and the current speed signal. And a second speed servo control means for controlling the feed speed of the moving body by increasing / decreasing the voltage applied to the angle adjusting means based on the speed deviation signal. By constructing the servo system, low-range speed fluctuations of about several Hz are performed by the feed drive motor, and high-range speed fluctuations of about several tens Hz are controlled by adjusting the tilt angle of the driven shaft with respect to the drive axis. Also, stable feed control can be realized against disturbance vibration such as rotational vibration, and feed accuracy can be improved. Further, in claim 2, when the servo band of the first speed servo control means is set to f 1 , the cutoff frequency f is applied to the second speed servo control means.
By providing the second phase compensator composed of the first-order or higher-order high-pass filter elements in which c is fc ≧ f 1, the first speed servo control means and the first speed servo control means with respect to low-range speed fluctuations of about several Hz are provided. It is possible to avoid the operation interference of the speed servo control means 2 and to realize more stable feed control,
Thereby, the feeding accuracy can be improved. In the third aspect, the second speed servo control means includes a second differential amplifier that outputs a speed deviation signal, a second phase compensator, a gain adjuster, and a second speed servo control means. Since a first switch for turning on / off, a drive amplifier for applying an operating voltage, and a constant voltage generating means are provided, a wide lead of several tens of μm to several mm can be realized, which enables high-resolution feed. This makes it possible to improve the feed accuracy at a narrow track pitch.

【００２３】また請求項４では、定電圧発生手段は、Ｃ
ＰＵ、ＲＯＭ、ＲＡＭとＣＰＵの指令により現在傾き角
度を算出する第１の演算部と、その結果から補正電圧を
演算する補正演算部と、その補正演算出力をアナログ信
号に変換する第２のＤ／Ａ変換器を設けているので、数
１０μｍ〜数ｍｍ程度の広いリードをソフトウェアによ
り実現できるので、フレキシブルな制御と駆動電圧の安
定的な供給を行うことができる。また請求項５では、角
度調整手段は、駆動軸の外周にころがり接触するローラ
を設けた従動軸の一端を球面軸受にて支持して、この回
動支持点を支点として駆動軸外周に押圧する自由支持と
し、前記の回動支持点を挟んでローラと反対側に、駆動
軸外周の接線方向で第１の弾性体の反力による回動支持
点周りのモーメント力を相殺するように伸縮する第２の
押圧手段を構成しているので、簡単な構造にて従動軸の
駆動軸に対する傾き角度を調整する角度調整手段を実現
でき、装置コストを安価にすることができる。また請求
項６では、前記請求項５に加えて、回動支持点を挟んで
ローラと反対側に、駆動軸の軸線と直角方向で第１の弾
性体の反力による回動支持点周りのモーメント力を相殺
する様に第１の押圧手段を設けているので、駆動軸に対
するローラの押圧調整が容易となり組立性を向上させる
ことができる。また請求項７では、第２の押圧手段をこ
のように構成することにより、第２の圧電素子に非線形
特性があってもサーボ制御により補償され、正確で自在
な交差角を形成できるので、安定した送り制御が実現で
き、送り精度の向上を図ることができる。Further, in claim 4, the constant voltage generating means is C
A first arithmetic unit that calculates a current tilt angle according to instructions from PU, ROM, RAM, and a CPU, a correction arithmetic unit that calculates a correction voltage from the result, and a second D that converts the correction arithmetic output into an analog signal. Since the / A converter is provided, a wide lead of several tens of μm to several mm can be realized by software, so that flexible control and stable supply of the driving voltage can be performed. Further, according to the present invention, the angle adjusting means supports one end of the driven shaft, which is provided with a roller in rolling contact with the outer periphery of the drive shaft, with a spherical bearing, and presses the rotation support point as a fulcrum against the outer periphery of the drive shaft. It is freely supported, and expands and contracts on the opposite side of the roller with the rotation support point interposed therebetween in the tangential direction of the outer periphery of the drive shaft so as to cancel out the moment force around the rotation support point due to the reaction force of the first elastic body. Since the second pressing means is configured, the angle adjusting means for adjusting the tilt angle of the driven shaft with respect to the drive shaft can be realized with a simple structure, and the device cost can be reduced. In addition, in addition to the above-mentioned claim 5, in the sixth aspect, on the side opposite to the roller with the rotation supporting point interposed, the rotation supporting point around the rotation supporting point by the reaction force of the first elastic body in the direction perpendicular to the axis of the drive shaft is provided. Since the first pressing means is provided so as to cancel the moment force, it is possible to easily adjust the pressing of the roller with respect to the drive shaft and improve the assembling property. Further, according to the present invention, by configuring the second pressing means in this way, even if the second piezoelectric element has a non-linear characteristic, it is compensated by the servo control and an accurate and free crossing angle can be formed, so that it is stable. The feed control can be realized, and the feed accuracy can be improved.

【００２４】また請求項８では、第１の押圧手段をこの
ように構成することにより、適正な予圧条件に瞬時に設
定でき、ローラや駆動軸の磨耗による経年変化に伴う予
圧の再調整も容易となると共に、部品交換時の予圧量再
現性も良好となり組立性の向上が図れる。また請求項９
では、第１の押圧手段をこのように構成することによ
り、ベースに固定される案内機構の固定部である支柱の
送り方向真直と、駆動軸の送り方向真直に誤差を生じて
組み立てが行われても、移動体が送り方向に動作した時
の組立誤差による予圧変動を生じることがなくなり、夫
々のローラと駆動軸外周で発生する駆動力にもばらつき
を発生しないので、長ストロークの駆動でも安定した送
り動作が実現でき、送り制御精度及び組立性の向上が図
れると共に、簡便な案内機構で構成できるので装置を安
価にすることができる。また請求項１０では、移動体が
送り方向に動作した時の組立誤差による予圧変動を生じ
ることがなくなり、夫々のローラと駆動軸外周で発生す
る駆動力にもばらつきを発生しないので、長ストローク
の駆動でも安定した送り動作が実現でき、送り制御精度
及び組立性の向上が図れるとともに簡便な案内機構で構
成できるので装置を安価にすることができる。また請求
項１１では、従動軸は、第１の押圧手段に用いる圧電素
子の伸縮量が小さくても大きな押圧ストロークが得られ
るので、駆動軸回りに配置する機構を小さくでき、装置
の小型化が図れる。Further, according to the present invention, by configuring the first pressing means in this way, it is possible to instantly set an appropriate preload condition, and it is easy to readjust the preload due to aging due to wear of the roller and the drive shaft. At the same time, the reproducibility of the preload amount at the time of component replacement is good, and the assemblability can be improved. Claim 9
Then, by constructing the first pressing means in this way, an error is caused between the feed direction straightness of the support column, which is the fixed portion of the guide mechanism fixed to the base, and the drive shaft feed direction straightness, and assembling is performed. Even if the moving body operates in the feed direction, preload fluctuation due to assembly error does not occur and the driving force generated on the outer periphery of each roller and the drive shaft does not vary, so it is stable even during long stroke driving. The feed operation can be realized, the feed control accuracy and the assemblability can be improved, and the device can be inexpensive because it can be configured with a simple guide mechanism. According to the tenth aspect, the preload fluctuation due to the assembly error when the moving body operates in the feeding direction does not occur, and the driving force generated at each roller and the outer circumference of the driving shaft does not vary, so that the long stroke The stable feeding operation can be realized even by driving, the feeding control accuracy and the assemblability can be improved, and the device can be made inexpensive because it can be configured with a simple guide mechanism. In the eleventh aspect, since the driven shaft can obtain a large pressing stroke even when the amount of expansion and contraction of the piezoelectric element used for the first pressing unit is small, the mechanism arranged around the drive shaft can be made small and the device can be downsized. Can be achieved.

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

【図１】本発明の第１の実施形態に係る摩擦駆動装置の
制御系構成図である。FIG. 1 is a configuration diagram of a control system of a friction drive device according to a first embodiment of the present invention.

【図２】本発明の図１の断面図である。2 is a sectional view of FIG. 1 of the present invention.

【図３】本発明の摩擦駆動装置の制御系の構成図であ
る。FIG. 3 is a configuration diagram of a control system of the friction drive device according to the present invention.

【図４】第１の速度サーボ制御手段及び第２の速度サー
ボ制御手段のゲイン曲線図である。FIG. 4 is a gain curve diagram of the first speed servo control means and the second speed servo control means.

【図５】本発明の定電圧発生手段のブロック図である。FIG. 5 is a block diagram of a constant voltage generating means of the present invention.

【図６】本発明の定電圧発生手段の角度補正電圧算出フ
ローチャートである。FIG. 6 is an angle correction voltage calculation flowchart of the constant voltage generating means of the present invention.

【図７】本発明の交差角度の詳細を示す図である。FIG. 7 is a diagram showing details of a crossing angle of the present invention.

【図８】本発明の圧電素子の電圧、変位特性図である。FIG. 8 is a voltage / displacement characteristic diagram of the piezoelectric element of the present invention.

【図９】本発明の第２の押圧板の断面構成図である。FIG. 9 is a cross-sectional configuration diagram of a second pressing plate of the present invention.

【図１０】本発明の第２のサーボ制御手段のブロック図
である。FIG. 10 is a block diagram of a second servo control means of the present invention.

【図１１】本発明の第１の押圧板の断面構成図である。FIG. 11 is a cross-sectional configuration diagram of a first pressing plate of the present invention.

【図１２】本発明の第１の押圧板の制御構成を示すブロ
ック図である。FIG. 12 is a block diagram showing a control configuration of a first pressing plate of the present invention.

【図１３】本発明の従動軸機構の周波数特性図である。FIG. 13 is a frequency characteristic diagram of the driven shaft mechanism of the present invention.

【図１４】本発明における交差角度とリードの関係を示
す図である。FIG. 14 is a diagram showing a relationship between a crossing angle and leads in the present invention.

【図１５】本発明の第３の変形量測定手段の構成図であ
る。FIG. 15 is a configuration diagram of a third deformation amount measuring means of the present invention.

【図１６】本発明の第４のサーボ制御手段のブロック図
である。FIG. 16 is a block diagram of a fourth servo control means of the present invention.

【図１７】本発明における従動軸の変位拡大機構図であ
る。FIG. 17 is a displacement magnifying mechanism diagram of the driven shaft in the present invention.

【図１８】本発明における複数の従動軸による構成図で
ある。FIG. 18 is a configuration diagram of a plurality of driven shafts according to the present invention.

【図１９】本発明における複数の従動軸による押圧制御
ブロック図である。FIG. 19 is a block diagram of a pressing control by a plurality of driven shafts according to the present invention.

【符号の説明】[Explanation of symbols]

１ 駆動軸、７ 従動軸、８ ローラ、９ａ ころがり
軸受２、１３ 移動体、１４ ころがり軸受、１５ａ
受光部、１５ｂ スケール、１６ 位置検出手段、１８
ターンテーブル、１９ エアスピンドル、２０ モー
タ、２１ 光学式ロータリエンコーダ、２２ 第１の固
定板、２３ 第２の固定板、８９ 支柱、９０ ベース1 drive shaft, 7 driven shaft, 8 roller, 9a rolling bearing 2, 13 moving body, 14 rolling bearing, 15a
Light receiving part, 15b scale, 16 position detecting means, 18
Turntable, 19 air spindle, 20 motor, 21 optical rotary encoder, 22 first fixing plate, 23 second fixing plate, 89 support, 90 base

Claims (11)

【特許請求の範囲】[Claims] 【請求項１】 固定されたベースと、該ベース側に回転
自在に支持された駆動軸と、該駆動軸の外径位置に所定
の傾斜角度をもって円周方向に配置された従動軸と、該
従動軸により回転自在に支持され且つ前記駆動軸の外周
にころがり接触するローラと、前記駆動軸の回転に伴っ
て駆動軸の軸方向に移動すると共に前記従動軸を支持す
る移動体と、該移動体の送り位置を検出する位置検出手
段と、前記駆動軸の回転角度位置を検出する角度検出手
段と、を備えた摩擦駆動装置であって、 前記駆動軸と従動軸との交差角度を自在に調整する角度
調整手段と、 前記移動体を前記駆動軸の軸方向に移動する送り指令信
号と前記位置検出手段の出力信号との差信号である速度
指令信号と前記位置検出手段の出力信号を周波数電圧変
換して得られる現在速度信号との差信号に基づいて送り
駆動モータへの印加電圧を増減して前記送り駆動モータ
の回転速度を制御する第１の速度サーボ制御手段と、 前記速度指令信号と現在速度信号の差信号である速度偏
差信号に基づいて、前記角度調整手段への印加電圧を増
減して前記従動軸の駆動軸に対する傾き角度を調整して
前記移動体の送り速度を制御する第２の速度サーボ制御
手段と、を備えたことを特徴とする摩擦駆動装置。1. A fixed base, a drive shaft rotatably supported on the base side, a driven shaft circumferentially disposed at an outer diameter position of the drive shaft at a predetermined inclination angle, A roller that is rotatably supported by a driven shaft and is in rolling contact with the outer periphery of the drive shaft; a moving body that moves in the axial direction of the drive shaft as the drive shaft rotates and that supports the driven shaft; A friction drive device comprising position detection means for detecting a body feeding position and angle detection means for detecting a rotational angular position of the drive shaft, wherein a crossing angle between the drive shaft and the driven shaft can be freely set. An angle adjusting means for adjusting, a speed command signal which is a difference signal between a feed command signal for moving the moving body in the axial direction of the drive shaft and an output signal of the position detecting means, and an output signal of the position detecting means are frequency Present obtained by voltage conversion First speed servo control means for controlling the rotational speed of the feed drive motor by increasing or decreasing the voltage applied to the feed drive motor based on the difference signal from the speed signal, and a difference signal between the speed command signal and the current speed signal. Second speed servo control means for controlling the feed speed of the moving body by increasing or decreasing the voltage applied to the angle adjusting means to adjust the inclination angle of the driven shaft with respect to the drive axis based on the speed deviation signal. And a friction drive device. 【請求項２】 前記第２の速度サーボ制御手段は、前記
第１の速度サーボ制御手段のサーボ帯域をｆ１としたと
きに遮断周波数ｆｃがｆｃ≧ｆ１なる関係を満足する１
次以上のハイパスフィルタ要素を有する第２の位相補償
器を備えたことを特徴とする請求項１に記載の摩擦駆動
装置。Wherein said second speed servo control means, satisfies said first speed cut-off frequency fc of the servo bandwidth of the servo control means when the f 1 becomes fc ≧ f 1 relationship 1
The friction drive device according to claim 1, further comprising a second phase compensator having high pass filter elements of the following or higher order. 【請求項３】 前記第２の速度サーボ制御手段は、前記
速度指令信号と現在速度信号に基づいて速度偏差信号を
出力する第２の差動増幅器と、 前記第２の位相補償器と、サーボ系の利得調整を行うゲ
イン調整器と、前記第２の速度サーボ制御手段のＯＮ／
ＯＦＦを行う第１のスイッチと、前記角度調整手段へ操
作電圧を印加する駆動アンプと、該駆動アンプへオフセ
ット電圧を印加する定電圧発生手段と、を備えたことを
特徴とする請求項１または２に記載の摩擦駆動装置。3. The second speed servo control means outputs a speed deviation signal based on the speed command signal and a current speed signal, a second differential amplifier, the second phase compensator, and a servo. A gain adjuster for adjusting the gain of the system, and ON / OFF of the second speed servo control means.
The first switch for turning off, a drive amplifier for applying an operating voltage to the angle adjusting means, and a constant voltage generating means for applying an offset voltage to the drive amplifier are provided. The friction drive device according to 2. 【請求項４】 前記定電圧発生手段は、制御を司るＣＰ
Ｕと、動作プログラムが記憶されたＲＯＭと、データの
書き込み／読み出しを行うＲＡＭと、 前記ＣＰＵの指令により前記位置検出手段のパルス出力
信号と前記角度検出手段からの１回転当たりの原点検出
信号から前記従動軸の前記駆動軸に対する現在傾き角度
を算出する演算部と、 該演算部の算出結果がゼロとなるように補正電圧を演算
する補正演算部と、 該補正演算出力をアナログ信号に変換するＤ／Ａ変換器
と、を備えたことを特徴とする請求項３に記載の摩擦駆
動装置。4. The CP which controls the constant voltage generating means.
U, a ROM in which an operation program is stored, a RAM for writing / reading data, a pulse output signal of the position detecting means and an origin detection signal per one rotation from the angle detecting means according to a command from the CPU. An arithmetic unit that calculates a current tilt angle of the driven shaft with respect to the drive axis, a correction arithmetic unit that calculates a correction voltage so that the calculation result of the arithmetic unit becomes zero, and the correction arithmetic output is converted into an analog signal. The friction drive device according to claim 3, further comprising a D / A converter. 【請求項５】 前記角度調整手段は、前記従動軸の一端
を球面軸受にて支持すると共にその支持の中心に回動支
持点を備え、 前記従動軸の他端を自由支持点とするために、前記従動
軸に設けたローラを前記回動支持点を支点として前記駆
動軸の外周に押圧する第１の弾性体及び前記駆動軸外周
の接線方向に押圧する第２の弾性体を備え、 前記回動支持点を挟んで前記ローラと反対側に、前記第
１の弾性体の反力による前記回動支持点周りのモーメン
ト力を相殺する方向に前記従動軸を押圧するように伸縮
する第２の圧電素子と前記従動軸の押圧力により変形す
る第２の変形部と該第２の変形部の変形量を検出する第
２の変形量測定手段と第２の押圧板とから構成される第
２の押圧手段と、を備えたことを特徴とする請求項１乃
至３の何れか一項に記載の摩擦駆動装置。5. The angle adjusting means supports one end of the driven shaft by a spherical bearing and has a rotation support point at the center of the support, and the other end of the driven shaft is a free support point. A first elastic body that presses the roller provided on the driven shaft to the outer circumference of the drive shaft with the rotation support point as a fulcrum, and a second elastic body that presses the roller in the tangential direction of the outer circumference of the drive shaft, A second elastic member that extends and contracts on the opposite side of the roller across the rotation support point so as to press the driven shaft in a direction that cancels the moment force around the rotation support point due to the reaction force of the first elastic body. Of the piezoelectric element, a second deforming portion that is deformed by the pressing force of the driven shaft, second deformation amount measuring means for detecting the deformation amount of the second deforming portion, and a second pressing plate. 2. The pressing unit according to claim 2, further comprising: Friction drive according to. 【請求項６】 前記角度調整手段は、前記従動軸の一端
を球面軸受にて支持すると共にその支持の中心に回動支
持点を備え、 前記従動軸の他端を自由支持点とするために、前記従動
軸に設けたローラを前記回動支持点を支点として前記駆
動軸の外周に押圧する第１の弾性体及び前記駆動軸外周
の接線方向に押圧する第２の弾性体を備え、 前記回動支持点を挟んで前記ローラと反対側に、前記駆
動軸の軸線と直角方向で前記第１の弾性体の反力による
前記回動支持点周りのモーメント力を相殺する方向に前
記従動軸を押圧するように伸縮する第１の圧電素子と第
１の押圧板とから構成される第１の押圧手段と、前記駆
動軸外周の接線方向で前記第２の弾性体の反力による前
記回動支持点周りのモーメント力を相殺する方向に前記
従動軸を押圧するように伸縮する第２の圧電素子と第２
の押圧板から構成される第２の押圧手段と、を備えたこ
とを特徴とする請求項１乃至３の何れか一項に記載の摩
擦駆動装置。6. The angle adjusting means supports one end of the driven shaft by a spherical bearing and has a rotation support point at the center of the support, and the other end of the driven shaft is a free support point. A first elastic body that presses the roller provided on the driven shaft to the outer circumference of the drive shaft with the rotation support point as a fulcrum, and a second elastic body that presses the roller in the tangential direction of the outer circumference of the drive shaft, The driven shaft is provided on the side opposite to the roller with the rotation support point interposed therebetween, and in a direction perpendicular to the axis of the drive shaft in a direction canceling out the moment force around the rotation support point due to the reaction force of the first elastic body. And a first pressing unit composed of a first pressing plate that expands and contracts so as to press, and the rotation by the reaction force of the second elastic body in a tangential direction of the outer periphery of the drive shaft. Press the driven shaft in a direction that cancels the moment force around the dynamic support point. The second piezoelectric element and a second which expands and contracts as
4. The friction drive device according to any one of claims 1 to 3, further comprising a second pressing unit configured by the pressing plate. 【請求項７】 前記第２の押圧手段は、前記Ｄ／Ａ変換
器と、前記第２の変形量測定手段と、 前記Ｄ／Ａ変換器の出力信号である押圧伸縮設定信号と
前記第２の変形量測定手段の出力信号である現在押圧伸
縮量を比較してサーボ動作を行う第２のサーボ制御手段
と、を備えたことを特徴とする請求項１乃至５の何れか
一項に記載の摩擦駆動装置。7. The second pressing means includes the D / A converter, the second deformation amount measuring means, a pressing expansion / contraction setting signal that is an output signal of the D / A converter, and the second pressing means. 6. A second servo control means for performing a servo operation by comparing a current pressing expansion / contraction amount which is an output signal of the deformation amount measuring means of 1. in accordance with any one of claims 1 to 5. Friction drive. 【請求項８】 前記第１の押圧手段は、一定電圧を発生
する定電圧回路と、 一方の端子を０Ｖ他方の端子に前記定電圧回路の出力信
号が接続され外部信号によりＯＮ／ＯＦＦする切換スイ
ッチと、 第１の押圧板の第１の変形部に設けた第１の変形量測定
手段と、 前記切換スイッチの出力信号である押圧伸縮設定信号と
前記第１の変形量測定手段の出力信号である現在押圧伸
縮量とを比較してサーボ制御する第１のサーボ制御手段
と、を備えたことを特徴とする請求項１乃至３又は５に
記載の摩擦駆動装置。8. The first pressing means includes a constant voltage circuit for generating a constant voltage, and switching for turning on / off an external signal by connecting an output signal of the constant voltage circuit to one terminal of 0V and the other terminal. A switch, a first deformation amount measuring means provided in the first deformation portion of the first pressing plate, a press expansion / contraction setting signal which is an output signal of the changeover switch, and an output signal of the first deformation amount measuring means. 6. The friction drive device according to claim 1, further comprising: first servo control means for performing servo control by comparing the present pressing expansion / contraction amount. 【請求項９】 前記第１の押圧手段は、ＣＰＵからのデ
ジタル信号をアナログ信号に変換する１つのＤ／Ａ変換
器と、 前記第１の押圧板と前記回動支持点とローラ間にあって
前記従動軸の押圧方向への変形量を検出する第３の変形
量測定手段と、 前記１つのＤ／Ａ変換器の出力信号である押圧設定信号
と前記第３の変形量測定手段の出力信号である現在押圧
量とを比較してサーボ制御する第４のサーボ制御手段
と、を備えたことを特徴とする請求項１乃至５又は７に
記載の摩擦駆動装置。9. The first pressing means is one D / A converter for converting a digital signal from a CPU into an analog signal, and is provided between the first pressing plate, the rotation support point and the roller, and Third deformation amount measuring means for detecting the deformation amount of the driven shaft in the pressing direction, a pressing setting signal which is an output signal of the one D / A converter, and an output signal of the third deformation amount measuring means. The friction drive device according to claim 1, further comprising: a fourth servo control unit that performs servo control by comparing a certain current pressing amount. 【請求項１０】 出力手段は、複数の圧電素子への押圧
設定信号を独立に与えるためにＣＰＵからのデジタル信
号をアナログ信号に変換する複数のＤ／Ａ変換器と、複
数の前記第３の変形量測定手段と、前記複数のＤ／Ａ変
換器の出力信号である押圧設定信号と前記複数の第３の
変形量測定手段の出力信号である現在押圧量とを比較し
てサーボ制御する第５のサーボ制御手段と、を備えてい
ることを特徴とする請求項１乃至３の何れか一項に記載
の摩擦駆動装置。10. The output means includes a plurality of D / A converters for converting a digital signal from the CPU into an analog signal in order to independently give a pressure setting signal to the plurality of piezoelectric elements, and a plurality of the third / third converters. Deformation amount measuring means, a pressure setting signal which is an output signal of the plurality of D / A converters, and a current pressing amount which is an output signal of the plurality of third deformation amount measuring means are compared to perform servo control. 5. The friction drive device according to claim 1, further comprising: 5 servo control means. 【請求項１１】 前記従動軸は、前記第１の押圧手段の
押圧点と前記回動支持点間距離をＬ１、前記第１の押圧
手段の押圧点とローラ間距離をＬ２とした時に、Ｌ２＞
Ｌ１の条件を満足する変位拡大機構を形成していること
を特徴とする請求項１乃至１０の何れか一項に記載の摩
擦駆動装置。11. The driven shaft is L2 when the distance between the pressing point of the first pressing means and the rotation supporting point is L1, and the distance between the pressing point of the first pressing means and the roller is L2. >
The friction drive device according to any one of claims 1 to 10, wherein a displacement magnifying mechanism satisfying the condition of L1 is formed.
JP2002151407A 2002-05-24 2002-05-24 Friction driving device Pending JP2003343676A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2002151407A JP2003343676A (en) 2002-05-24 2002-05-24 Friction driving device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2002151407A JP2003343676A (en) 2002-05-24 2002-05-24 Friction driving device

Publications (1)

Publication Number Publication Date
JP2003343676A true JP2003343676A (en) 2003-12-03

Family

ID=29769006

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2002151407A Pending JP2003343676A (en) 2002-05-24 2002-05-24 Friction driving device

Country Status (1)

Country Link
JP (1) JP2003343676A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102849439A (en) * 2012-09-28 2013-01-02 山东爱通工业机器人科技有限公司 Feeder

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102849439A (en) * 2012-09-28 2013-01-02 山东爱通工业机器人科技有限公司 Feeder
CN102849439B (en) * 2012-09-28 2014-07-09 山东爱通工业机器人科技有限公司 Feeder

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