JP2011143503A

JP2011143503A - Cylindrical grinder

Info

Publication number: JP2011143503A
Application number: JP2010005966A
Authority: JP
Inventors: Makoto Tano; 誠田野
Original assignee: JTEKT Corp
Current assignee: JTEKT Corp
Priority date: 2010-01-14
Filing date: 2010-01-14
Publication date: 2011-07-28

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the chattering of work W generated during the grinding of a cylindrical grinder 1. <P>SOLUTION: During grinding, a phase of chattering at a measuring point of a machined portion, work rotation speed, and the cycle of chattering are detected to calculate a present grinding action surface of a grinding wheel 7 at a grinding action point and a phase of relative displacement. The relative position of the work and the grinding wheel is displaced to a phase opposite to the calculated phase of the relative displacement by a relative position controlling means, reducing the chattering of the machined portion in process. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、円筒研削盤に関するものであり、詳しくは工作物の研削に伴い工作物の被加工部に生じる、円周方向に分布する理想形状に対する凹凸であるビビリの低減に関するものである。 The present invention relates to a cylindrical grinder, and more particularly, to reduction of chatter that is an unevenness with respect to an ideal shape distributed in a circumferential direction, which occurs in a workpiece portion of a workpiece as the workpiece is ground.

円筒研削盤においてはビビリと言われる加工精度不良が発生することがある。ビビリとは工作物の加工表面に生じる微小な凹凸で、工作物の１回転中に工作物と砥石研削作用面の相対位置が振動的に変動するときに生じる。砥石車の研削作用面の振れは、砥石車のアンバランスや砥石車回転軸の振動があると生じる。工作物の振動は、工作物の回転駆動部に振動を生じることや、工作物のセンター穴の真円度不良がある場合などに生じる。以上のような、砥石車の振れと工作物の振動が合成された砥石車の研削作用面と工作物の相対位置の変動によりビビリが発生する。
ビビリの特徴は、上記の発生原因から周期性を持つことであり、ほとんどの場合は砥石車の研削作用面の振れが主要因である。 In a cylindrical grinder, a processing accuracy defect called chatter may occur. Chatter is a minute unevenness generated on the machining surface of the workpiece, and occurs when the relative position of the workpiece and the grinding wheel grinding surface fluctuates in vibration during one rotation of the workpiece. The wobbling of the grinding surface of the grinding wheel occurs when the grinding wheel is unbalanced or the grinding wheel rotation shaft vibrates. The vibration of the workpiece occurs when vibration is generated in the rotational drive unit of the workpiece or when the roundness of the center hole of the workpiece is poor. As described above, chattering occurs due to a change in the relative position of the workpiece and the grinding surface of the grinding wheel in which the grinding wheel vibration and the workpiece vibration are combined.
The feature of chattering is that it has periodicity due to the above-mentioned cause of occurrence, and in most cases, the main factor is runout of the grinding surface of the grinding wheel.

従来のビビリ防止技術としては、ビビリの原因である砥石車の振動を低減するために砥石のアンバランスを自動補正する従来技術１（例えば、特許文献１参照）や、工作物の加工面を基準として工具と工作物の相対変位を補正する従来技術２（例えば、非特許文献１参照）がある。 Conventional chattering prevention techniques include the conventional technique 1 (for example, see Patent Document 1) that automatically corrects the grinding wheel unbalance in order to reduce the vibration of the grinding wheel, which is the cause of chattering, and the work surface of the workpiece. As a conventional technique 2 for correcting the relative displacement between the tool and the workpiece (for example, see Non-Patent Document 1).

砥石車にアンバランスがあり振れを発生している場合、その状態でツルーイングを行うとツルアに対してはほぼ振れの無い砥石車の研削作用面が得られる。そのためツルーイング装置を工作物と近い位置に配置することで、工作物に対する砥石車の研削作用面の振れを低減することが可能で、そのような機械構成が多い。しかし、砥石車に吸収されたクーラント液の偏在によるアンバランスのように、時間と共にアンバランス量が変動する場合は上記の構成だけでは対応ができない。この場合、特許文献１に示される従来技術１のような、砥石車のバランスを自動で補正するオートバランス装置が使用される。 When the grinding wheel is unbalanced and shakes, if the truing is performed in this state, a grinding surface of the grinding wheel that is substantially free of shake with respect to the truer can be obtained. Therefore, by arranging the truing device at a position close to the workpiece, it is possible to reduce runout of the grinding surface of the grinding wheel with respect to the workpiece, and there are many such mechanical configurations. However, if the amount of unbalance varies with time, such as unbalance due to uneven distribution of coolant liquid absorbed by the grinding wheel, it is not possible to cope with the above configuration alone. In this case, an automatic balance device that automatically corrects the balance of the grinding wheel, such as the prior art 1 disclosed in Patent Document 1, is used.

非特許文献１に記された旋盤加工における従来技術２の精度補正技術の概要を以下に説明する。
図１２に示すように、回転する工作物Ｗの片側にバイト４１を備え、反対側に工具保持台４０と工作物Ｗの加工終了面の相対位置を計測する変位検出器４２を備え、工具保持台４０に対してバイト４１を切込み方向に移動可能に保持した構造である。加工中に、変位検出器４２により検出された工作物Ｗと工具保持台４０の相対変位を打ち消すようにバイト４１を切込み方向に移動させ、工作物Ｗと工具４１の外乱による相対変位を低減することによりビビリなどの加工面の精度低下を防止する。 The outline of the accuracy correction technique of the conventional technique 2 in the lathe processing described in Non-Patent Document 1 will be described below.
As shown in FIG. 12, a tool 41 is provided with a cutting tool 41 on one side of a rotating workpiece W, and a displacement detector 42 for measuring the relative position of the tool holding table 40 and the machining end surface of the workpiece W on the opposite side. In this structure, the cutting tool 41 is held so as to be movable in the cutting direction with respect to the table 40. During machining, the cutting tool 41 is moved in the cutting direction so as to cancel the relative displacement between the workpiece W and the tool holder 40 detected by the displacement detector 42, and the relative displacement due to the disturbance of the workpiece W and the tool 41 is reduced. This prevents deterioration of the machined surface accuracy such as chatter.

特開平１１−１２５３１１号公報Japanese Patent Laid-Open No. 11-12531

「精密工学会誌１９９３年５９巻６号」、精密工学会、１９９３年、ｐ．８７〜ｐ．９１“The Journal of Precision Engineering, Vol. 59, No. 6, 1993”, Precision Engineering Society, 1993, p. 87-p. 91

特許文献１に示す従来技術では砥石車の振れを低減してビビリを防止できるが、工作物の振動に起因するビビリは防止できない。また、オートバランス装置は振動検出装置、バランス駆動装置などを、砥石軸部に組込むため砥石軸部が大型となり、高価である。さらに、オートバランス中は研削を中断しなければならず稼働率が低下する。
非特許文献１に示す従来技術では砥石車保持部と工作物の相対変位による誤差は低減できるが、砥石車の振れに起因する誤差を検出することができない。結果として、砥石車の研削作用面の振れに起因するビビリをインプロセスで低減できない。
以上の他に、工作物の加工精度を加工完了後に計測して誤差を求め、誤差分の補正を加えて再加工して精度を向上することは一般的に実施されているが、この場合計測、再加工の余分な工程が必要となり、コストと加工時間が増加する。 In the prior art shown in Patent Document 1, chattering due to vibration of a workpiece cannot be prevented, although chattering of the grinding wheel can be reduced to prevent chattering. Further, since the auto balance device incorporates a vibration detection device, a balance drive device, and the like into the grindstone shaft portion, the grindstone shaft portion becomes large and expensive. Furthermore, grinding must be interrupted during auto-balancing, and the operating rate decreases.
In the prior art shown in Non-Patent Document 1, errors due to the relative displacement between the grinding wheel holding portion and the workpiece can be reduced, but errors due to wobbling of the grinding wheel cannot be detected. As a result, chatter due to runout of the grinding surface of the grinding wheel cannot be reduced in-process.
In addition to the above, it is generally practiced to improve the accuracy by measuring the machining accuracy of the workpiece after completion of machining to determine the error and reworking it after correcting the error. Therefore, an extra process of reworking is required, and cost and processing time are increased.

本発明は上記事情に鑑みてなされたものであり、インプロセスでビビリを低減する円筒研削盤を提供することを目的とする。 This invention is made | formed in view of the said situation, and it aims at providing the cylindrical grinder which reduces chatter by an in-process.

上記の課題を解決するため、請求項１に係る発明の特徴は、円筒状の工作物を支持して回転駆動させる工作物支持手段と、
砥石車を支持し回転駆動させる砥石車支持手段と、
前記工作物支持手段と前記砥石車支持手段とを相対移動させ、前記砥石車で前記工作物を研削する駆動手段と、
前記工作物の研削に伴い前記工作物の被加工部に生じる円周方向に分布する理想形状に対する凹凸であるビビリの研削作用点での位相を検出する位相検出手段と、
前記工作物と前記砥石車の相対変位を、前記研削作用点での前記ビビリの位相から判定した前記工作物と前記砥石車の相対変位の位相と、逆位相に変位させる相対位置制御手段と、
を備えることである。 In order to solve the above-mentioned problem, the feature of the invention according to claim 1 is that a workpiece support means for supporting and rotating a cylindrical workpiece,
A grinding wheel support means for supporting and rotating the grinding wheel;
Driving means for relatively moving the workpiece support means and the grinding wheel support means and grinding the workpiece with the grinding wheel;
Phase detection means for detecting a phase at a grinding action point of chattering that is unevenness with respect to an ideal shape distributed in a circumferential direction generated in a workpiece portion of the workpiece as the workpiece is ground;
A relative position control means for displacing the relative displacement between the workpiece and the grinding wheel from the phase of the chatter at the grinding action point and the phase of the relative displacement between the workpiece and the grinding wheel;
It is to provide.

請求項２に係る発明の特徴は、請求項１に係る発明において、前記被加工部の前記ビビリの振幅を検出するビビリ振幅検出手段を備え、前記相対位置制御手段を前記ビビリの振幅に比例した作動量で作動させることである。 A feature of the invention according to claim 2 is that in the invention according to claim 1, there is provided chatter amplitude detecting means for detecting the amplitude of the chatter of the workpiece, and the relative position control means is proportional to the amplitude of the chatter. It is to operate with the operating amount.

請求項３に係る発明の特徴は、請求項２に係る発明において、前記被加工部の前記ビビリの振幅が所定の値より小さくなったときに研削を終了することである。 A feature of the invention according to claim 3 is that, in the invention according to claim 2, the grinding is finished when the amplitude of the chatter of the workpiece becomes smaller than a predetermined value.

請求項４に係る発明の特徴は、請求項１〜請求項３のいずれか１項に係る発明において、前記位相検出手段を
被加工部の前記ビビリの周期を検出するビビリ周期検出手段と、
前記工作物の外周の所定の円周方向位置である測定点での前記ビビリの位相を検出する測定点位相検出手段と、
前記工作物の回転速度を検出する回転速度検出手段と、
前記ビビリ周期検出手段により検出された前記ビビリの周期と前記測定点位相検出手段により検出されたビビリの位相と、前記回転速度検出手段にて検出された前記工作物の回転速度と、から前記工作物の前記研削作用点での前記ビビリの位相を算出するビビリ演算手段と、
で構成することである。 According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the phase detection unit is a chatter cycle detection unit that detects the cycle of the chatter of the workpiece,
Measurement point phase detection means for detecting the phase of the chatter at a measurement point which is a predetermined circumferential position on the outer periphery of the workpiece;
Rotation speed detection means for detecting the rotation speed of the workpiece;
From the chatter cycle detected by the chatter cycle detector, the chatter phase detected by the measurement point phase detector, and the rotational speed of the workpiece detected by the rotational speed detector, the workpiece A chatter calculating means for calculating a phase of the chatter at the grinding action point of the object;
It is composed of.

請求項５に係る発明の特徴は、請求項１〜請求項３のいずれか１項に係る発明において、前記位相検出手段を
前記砥石車の回転周期を検出する砥石車回転周期検出手段と、
前記工作物の外周の所定の円周方向位置である測定点での前記ビビリの位相を検出する前記測定点位相検出手段と、
前記工作物の回転速度を検出する回転速度検出手段と、
前記砥石車回転周期検出手段により検出された前記砥石車の回転周期と、前記測定点位相検出手段により検出されたビビリの位相と、前記回転速度検出手段にて検出された前記工作物の回転速度と、から前記工作物の前記研削作用点での前記ビビリの位相を算出するビビリ演算手段と、
で構成することである。 A feature of the invention according to claim 5 is that, in the invention according to any one of claims 1 to 3, the phase detection means includes a grinding wheel rotation period detection means for detecting a rotation period of the grinding wheel,
The measurement point phase detection means for detecting the phase of the chatter at a measurement point which is a predetermined circumferential position on the outer periphery of the workpiece;
Rotation speed detection means for detecting the rotation speed of the workpiece;
The rotation cycle of the grinding wheel detected by the grinding wheel rotation cycle detection means, the chatter phase detected by the measurement point phase detection means, and the rotation speed of the workpiece detected by the rotation speed detection means And a chatter calculating means for calculating a phase of the chatter at the grinding action point of the workpiece from
It is composed of.

請求項６に係る発明の特徴は、請求項１〜請求項３のいずれか１項に係る発明において、前記位相検出手段を
前記砥石車支持手段の振動周期を検出する砥石振動周期検出手段と、
前記工作物の外周の所定の円周方向位置である測定点での前記ビビリの位相を検出する測定点位相検出手段と、
前記工作物の回転速度を検出する回転速度検出手段と、
前記砥石振動周期検出手段により検出された前記砥石車支持手段の振動周期と、前記測定点位相検出手段により検出されたビビリの位相と、前記回転速度検出手段にて検出された前記工作物の回転速度と、から前記工作物の前記研削作用点での前記ビビリの位相を算出するビビリ演算手段と、
で構成することである。 The invention according to claim 6 is characterized in that, in the invention according to any one of claims 1 to 3, the phase detection means comprises a grinding wheel vibration period detection means for detecting a vibration period of the grinding wheel support means,
Measurement point phase detection means for detecting the phase of the chatter at a measurement point which is a predetermined circumferential position on the outer periphery of the workpiece;
Rotation speed detection means for detecting the rotation speed of the workpiece;
The vibration cycle of the grinding wheel support means detected by the grinding wheel vibration period detection means, the chatter phase detected by the measurement point phase detection means, and the rotation of the workpiece detected by the rotation speed detection means A chatter calculating means for calculating the chatter phase at the grinding action point of the workpiece from the speed;
It is composed of.

請求項７に係る発明の特徴は、請求項１〜請求項３のいずれか１項に係る発明において、前記位相検出手段を前記砥石車支持手段の前記砥石車の前記工作物切込み方向の振動位相を検出する砥石振動位相検出手段で構成することである。 According to a seventh aspect of the present invention, in the invention according to any one of the first to third aspects, the phase detection means is a vibration phase of the grinding wheel in the grinding wheel of the grinding wheel of the grinding wheel support means. It is comprised with the grindstone vibration phase detection means which detects this.

請求項８に係る発明の特徴は、請求項１〜請求項７のいずれか１項に係る発明において、前記相対位置制御手段を前記工作物を変位させる工作物変位手段で構成することである。 A feature of the invention according to claim 8 is that, in the invention according to any one of claims 1 to 7, the relative position control means is constituted by a workpiece displacement means for displacing the workpiece.

請求項９に係る発明の特徴は、請求項８に係る発明において、前記工作物変位手段を前記工作物の研削作用点と１８０度位相がずれた位置で前記工作物の被加工部に接触して押圧する工作物押付け装置で構成し、
前記工作物押付け装置を、前記研削作用点での前記ビビリの位相から判定した前記工作物と前記砥石車の相対変位の位相と逆位相に変位させるような変位量から、前記工作物押付け装置が接触する前記工作物の被加工部における前記ビビリの凹凸高さを差し引いた値で制御することである。 A feature of the invention according to claim 9 is that, in the invention according to claim 8, the workpiece displacing means is brought into contact with the workpiece portion of the workpiece at a position 180 degrees out of phase with the grinding action point of the workpiece. It consists of a workpiece pressing device that presses
From the amount of displacement that causes the workpiece pressing device to be displaced in a phase opposite to the phase of relative displacement between the workpiece and the grinding wheel determined from the chatter phase at the grinding action point, the workpiece pressing device is It is controlling by the value which subtracted the uneven | corrugated height of the said chatter in the to-be-processed part of the said workpiece which contacts.

請求項１０に係る発明の特徴は、請求項９に係る発明において、前記相対位置制御手段の駆動に圧電素子を用いることである。 A feature of the invention according to claim 10 is that, in the invention according to claim 9, a piezoelectric element is used for driving the relative position control means.

請求項１１に係る発明の特徴は、請求項４に係る発明において、前記ビビリ周期検出手段を前記被加工部の凹凸を検知する凹凸検知手段により前記凹凸の周期を検出することで構成することである。 A feature of the invention according to claim 11 is that, in the invention according to claim 4, the chatter cycle detecting means is constituted by detecting the period of the irregularities by means of the irregularity detecting means for detecting irregularities of the workpiece. is there.

請求項１２に係る発明の特徴は、請求項２〜請求項６のいずれか1項に係る発明において、前記ビビリ振幅検出手段を前記被加工部の凹凸を検知する凹凸検知手段により前記凹凸の振幅を検出することで構成することである。 According to a twelfth aspect of the present invention, in the invention according to any one of the second to sixth aspects, the amplitude of the unevenness is detected by the unevenness detecting means for detecting the unevenness of the processed part. It is constituted by detecting.

請求項１３に係る発明の特徴は、請求項４〜請求項６のいずれか１項に係る発明において、前記測定点位相検出手段を前記被加工部の凹凸を検知する凹凸検知手段により前記凹凸の位相を検出することで構成することである。 According to a thirteenth aspect of the present invention, in the invention according to any one of the fourth to sixth aspects, the measurement point phase detection means can detect the unevenness by means of an unevenness detection means that detects the unevenness of the workpiece. It is configured by detecting the phase.

請求項１４に係る発明の特徴は、請求項１１〜請求項１３のいずれか１項に係る発明において、前記凹凸検出手段と被加工部の下部が接触するように配置することである。 A feature of the invention according to claim 14 is that, in the invention according to any one of claims 11 to 13, it is arranged so that the unevenness detecting means and the lower part of the part to be processed are in contact with each other.

請求項１に係る発明によれば、研削中の研削作用点で砥石車の研削作用面と工作物の相対変位により発生するビビリの位相を位相検出手段により検出し、相対位置制御手段でビビリの相対変位と逆の位相で砥石車と工作物とを相対運動をさせることで、ビビリの振幅を低減できる。以上の作用をインプロセスで実施できるため、ビビリ低減のための余分な工程が不要であり、加工時間の増大が防止できる。 According to the first aspect of the present invention, the phase of the chatter generated by the relative displacement between the grinding surface of the grinding wheel and the workpiece is detected by the phase detection means at the grinding action point during grinding, and the chatter is detected by the relative position control means. By causing the grinding wheel and the workpiece to move relative to each other in a phase opposite to the relative displacement, the chattering amplitude can be reduced. Since the above operation can be performed in-process, an extra step for reducing chatter is unnecessary, and an increase in processing time can be prevented.

請求項２に係る発明によれば、相対位置制御手段を現在発生中のビビリの振幅を打ち消す最適な振幅で作動させることができ、ビビリ低減効果を大きくできる。 According to the invention which concerns on Claim 2, a relative position control means can be operated by the optimal amplitude which negates the amplitude of the chatter currently generated, and a chatter reduction effect can be enlarged.

請求項３に係る発明によれば、被加工部のビビリの振幅が所定の値より小さくなったときに研削を終了することができ、所望の表面精度の工作物を最短時間で加工できる。 According to the invention which concerns on Claim 3, grinding can be complete | finished when the amplitude of the chatter of a to-be-processed part becomes smaller than predetermined value, and the workpiece of the desired surface precision can be processed in the shortest time.

請求項４に係る発明によれば、被加工部の実際のビビリに基づき相対位置制御手段を作動させるので、いかなる原因のビビリに対してもてビビリを低減できる。 According to the invention which concerns on Claim 4, since a relative position control means is operated based on the actual chatter of a to-be-processed part, chatter can be reduced with respect to chatter of any cause.

請求項５に係る発明によれば、位相検出手段の構成に必要なビビリ周期として、簡便な砥石車回転周期検出手段により検出できる砥石車の回転周期を代用するので、位相検出手段を低コストに構成できる。 According to the fifth aspect of the present invention, since the rotation cycle of the grinding wheel that can be detected by a simple grinding wheel rotation cycle detection unit is used as the chatter cycle necessary for the configuration of the phase detection unit, the phase detection unit can be reduced in cost. Can be configured.

請求項６に係る発明によれば、位相検出手段の構成に必要なビビリ周期として、簡便な砥石台振動周期検出手段により検出できる砥石台の振動周期を代用するので、位相検出手段を低コストに構成できる。 According to the sixth aspect of the present invention, since the vibration cycle of the grinding wheel platform that can be detected by a simple grinding wheel platform vibration cycle detection unit is used as the chatter cycle necessary for the configuration of the phase detection unit, the phase detection unit can be reduced in cost. Can be configured.

請求項７に係る発明によれば、位相検出手段として、簡便な砥石台振動位相検出手段を代用するので、位相検出手段を低コストに構成できる。 According to the seventh aspect of the invention, since the simple grindstone vibration phase detection means is used as the phase detection means, the phase detection means can be configured at low cost.

請求項８に係る発明によれば、砥石車に対して質量の小さい工作物を変位させることにより相対位置制御手段を構成するができ、応答性の高いビビリ低減制御ができる。このため、砥石車が高速回転する高能率研削加工においてもビビリ低減が可能である。 According to the invention which concerns on Claim 8, a relative position control means can be comprised by displacing a workpiece | work with small mass with respect to a grinding wheel, and chatter reduction control with high responsiveness can be performed. For this reason, chatter can be reduced even in high-efficiency grinding where the grinding wheel rotates at high speed.

請求項９に係る発明によれば、被加工部に相対位置制御手段を接触させて工作物を変位させるので、工作物に相対位置制御手段の接触部位を特別に設けることなく本発明を実施できる。また、砥石車法線方向の研削抵抗を支えて工作物のたわみを防止する振れ止め機能を合わせて持つことができる。 According to the ninth aspect of the present invention, the relative position control means is brought into contact with the workpiece and the work piece is displaced. Therefore, the present invention can be implemented without providing a special contact portion of the relative position control means on the work piece. . Further, it can have a steadying function for supporting the grinding resistance in the normal direction of the grinding wheel to prevent the workpiece from being bent.

請求項１０に係る発明によれば、相対位置制御手段の駆動に圧電素子を用いるので、高応答で高負荷の制御ができる相対位置制御手段をコンパクトに構成できる。 According to the invention of claim 10, since the piezoelectric element is used for driving the relative position control means, the relative position control means capable of high response and high load control can be configured compactly.

請求項１１に係る発明によれば、被加工部の凹凸を検知する凹凸検知手段によりビビリ周期を検出するので正確なビビリ周期の検出ができ、高精度なビビリ低減制御が可能である。 According to the eleventh aspect of the present invention, since the chatter cycle is detected by the projection / depression detecting means for detecting the projection / depression of the workpiece, an accurate chatter cycle can be detected, and highly accurate chatter reduction control is possible.

請求項１２に係る発明によれば、凹凸検知手段により被加工部の凹凸の振幅を検出することでビビリ振幅を正確に検出するので、最適な振幅の相対位置制御手段の作動が可能で、効果的にビビリ低減ができる。 According to the twelfth aspect of the invention, since the chatter amplitude is accurately detected by detecting the amplitude of the unevenness of the workpiece by the unevenness detecting means, it is possible to operate the relative position control means with the optimum amplitude, and the effect The chatter can be reduced.

請求項１３に係る発明によれば、凹凸検知手段により被加工部のビビリ位相を正確に検出するので、位相誤差の小さい逆位相の相対位置制御手段の作動が可能で、効果的にビビリを低減ができる。 According to the thirteenth aspect of the present invention, since the chatter phase of the workpiece is accurately detected by the unevenness detecting means, it is possible to operate the relative position control means of the opposite phase with a small phase error, and effectively reduce chatter. Can do.

請求項１４に係る発明によれば、前記凹凸検出手段と被加工部の下部が接触するように配置するので、工作物の自重と研削抵抗による工作物の下方向へのたわみを防止する振れ止め機能を合わせて持つことができる。 According to the invention of claim 14, since the unevenness detecting means and the lower part of the workpiece are arranged so as to be in contact with each other, the steady rest that prevents the workpiece from bending downward due to its own weight and grinding resistance. It can have both functions.

第１の実施形態の円筒研削盤の全体構成を示す概略図である。It is the schematic which shows the whole structure of the cylindrical grinding machine of 1st Embodiment. 図１の上面図である。FIG. 2 is a top view of FIG. 1. 第１の実施形態の凹凸検出装置と工作物押付け装置を示す概略図である。It is the schematic which shows the unevenness | corrugation detection apparatus and workpiece pressing apparatus of 1st Embodiment. 第１の実施形態の要素配置を示す概略図である。It is the schematic which shows the element arrangement | positioning of 1st Embodiment. 第１の実施形態の研削作用点ビビリ検出手段と工作物押付け装置の関係を示すブロック図である。It is a block diagram which shows the relationship between the grinding action point chatter detection means and workpiece pressing apparatus of 1st Embodiment. 第１の実施形態のビビリ位相検出原理を示す概念図である。It is a conceptual diagram which shows the chatter phase detection principle of 1st Embodiment. 第１の実施形態のデータの関係を示す表である。It is a table | surface which shows the relationship of the data of 1st Embodiment. 第１の実施形態のビビリ低減作動を示すフローチャート図である。It is a flowchart figure which shows the chatter reduction operation | movement of 1st Embodiment. 第２の実施形態の研削作用点ビビリ検出手段と工作物押付け装置の関係を示すブロック図である。It is a block diagram which shows the relationship between the grinding action point chatter detection means and workpiece pressing apparatus of 2nd Embodiment. 第３実施形態の研削作用点ビビリ検出手段と工作物押付け装置の関係を示すブロック図である。It is a block diagram which shows the relationship between the grinding action point chatter detection means and workpiece pressing apparatus of 3rd Embodiment. 第４実施形態の研削作用点ビビリ検出手段と工作物押付け装置の関係を示すブロック図である。It is a block diagram which shows the relationship between the grinding action point chatter detection means and workpiece pressing apparatus of 4th Embodiment. 従来技術２の原理を示す概念図である。It is a conceptual diagram which shows the principle of the prior art 2. FIG.

＜第１の実施形態＞
以下、本発明の第１の実施形態を円筒工作物を研削する円筒研削盤の実施事例に基づき、図１〜図６を参照しつつ説明する。
図２に示すように、研削盤１は、ベッド２とベッド２上にＸ軸方向に往復可能な砥石台３と、テーブル４を備えている。砥石台３は砥石軸８を回転自在に支持し、砥石軸８を回転させる砥石軸回転モータ（図示省略する）を備えており、砥石車７は砥石軸８に着脱自在に装着されて回転駆動される。テーブル４上には、工作物Ｗの一端を把持して回転自在に支持し主軸モータ（図示省略する）により回転駆動される主軸５と、工作物Ｗの他端を回転自在に支持する心押台６を備えており、工作物Ｗは主軸５と心押台６により支持されて、研削加工時に回転駆動される。
図１に示すように、テーブル４上には架台９が設置され、架台９により工作物Ｗの被加工部の下部に接触して被加工部の凹凸を検出する凹凸検出装置１０と、被加工部外周の研削作用点と対向した位置で被加工部に接触して、工作物Ｗに変位を与え砥石車７と工作物Ｗの相対位置を制御する工作物押付け装置１１が保持される。 <First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 6 based on an implementation example of a cylindrical grinder for grinding a cylindrical workpiece.
As shown in FIG. 2, the grinding machine 1 includes a bed 2, a grindstone bed 3 that can reciprocate on the bed 2 in the X-axis direction, and a table 4. The grinding wheel base 3 includes a grinding wheel shaft rotating motor (not shown) that rotatably supports the grinding wheel shaft 8 and rotates the grinding wheel shaft 8. The grinding wheel 7 is detachably mounted on the grinding wheel shaft 8 and is driven to rotate. Is done. On the table 4, a spindle 5 that grips and rotatably supports one end of the workpiece W and is rotated by a spindle motor (not shown), and a tailstock that rotatably supports the other end of the workpiece W. A work table W is provided, and the workpiece W is supported by the spindle 5 and the tailstock 6 and is driven to rotate during grinding.
As shown in FIG. 1, a gantry 9 is installed on the table 4, and a concavo-convex detection device 10 that detects the concavo-convex of the workpiece by contacting the lower portion of the workpiece W with the gantry 9, and the workpiece A workpiece pressing device 11 that holds the workpiece W in contact with the workpiece at a position opposite to the grinding action point on the outer periphery of the portion and applies displacement to the workpiece W to control the relative position between the grinding wheel 7 and the workpiece W is held.

研削盤１は、所定のプログラムを実行することで自動化された研削加工を実行する制御装置３０を備えている。制御装置３０の機能的構成として、砥石台３の送りを制御するＸ軸制御手段３１、主軸５の回転を制御する主軸制御手段３２、研削作用点のビビリを検出する研削作用点ビビリ検出手段３３、工作物押付装置１１を制御する工作物押付け制御手段３４などを具備している。また、主軸制御手段３２の内部には主軸５の回転速度を検出する主軸回転速度検出手段３２１を備えている。 The grinding machine 1 includes a control device 30 that executes automated grinding by executing a predetermined program. As a functional configuration of the control device 30, an X-axis control means 31 that controls the feed of the grinding wheel table 3, a spindle control means 32 that controls the rotation of the spindle 5, and a grinding action point chatter detection means 33 that detects chatter at the grinding action point. Further, a workpiece pressing control means 34 for controlling the workpiece pressing device 11 is provided. The main shaft control means 32 is provided with main shaft rotation speed detection means 321 for detecting the rotation speed of the main shaft 5.

図３に示すように、凹凸検出装置１０は、架台９に底部を固定された圧電素子１０１と、圧電素子１０１の上部に接合され架台９に対して摺動自在に上下できるプランジャー１０２と、プランジャー１０２の先端に装着され工作物Ｗに接触する接触子１０３で構成される。圧電素子１０１は工作物の回転に伴うビビリの凹凸による接触力の変動に応じた電圧を発生し、電圧検出器１２を介して制御装置３０へ検出信号を送る。
工作物押付装置１１は、架台９に一端を固定された圧電素子１１１と、圧電素子１１１の他端に接合され架台９に対して摺動自在に前後できるプランジャー１１２と、プランジャー１１２の先端に装着され工作物Ｗに接触する接触子１１３で構成される。圧電素子１１１は圧電素子ドライバ１３を介して制御装置３０により駆動される。 As shown in FIG. 3, the unevenness detecting device 10 includes a piezoelectric element 101 whose bottom is fixed to the gantry 9, a plunger 102 that is joined to the top of the piezoelectric element 101 and can be slidably moved up and down with respect to the gantry 9, The contact 103 is attached to the tip of the plunger 102 and contacts the workpiece W. The piezoelectric element 101 generates a voltage corresponding to fluctuations in the contact force due to chatter irregularities accompanying the rotation of the workpiece, and sends a detection signal to the control device 30 via the voltage detector 12.
The workpiece pressing device 11 includes a piezoelectric element 111 having one end fixed to the gantry 9, a plunger 112 joined to the other end of the piezoelectric element 111 and capable of sliding back and forth with respect to the gantry 9, and a tip of the plunger 112. It is comprised with the contactor 113 with which it mounts | wears and contacts the workpiece W. The piezoelectric element 111 is driven by the control device 30 via the piezoelectric element driver 13.

上述のような円筒研削盤によりビビリが低減される作用を図４、５、６に基づき以下に説明する。
図４に示すように、凹凸検出装置１０の接触子１０３は、研削作用点からの工作物回転方向への角度がα度の凹凸検出位置で、工作物Ｗの被加工部の下部に常に接触するように配置される。工作物押付け装置１１の接触子１１３は、工作物回転方向で凹凸検出位置までの角度がβ度の工作物Ｗの研削作用点と対向する工作物押込み位置で、被加工部に常に接触するように配置される。
凹凸検出装置１０は工作物回転によるビビリの凹凸変動に伴う荷重変動を圧電素子１０１で検出し、電圧として電圧検出器１２に出力する。このとき、荷重変動はビビリの振幅に比例し凸部の頂点で最大となり凹部で最低となり、電圧出力も同様に変動する。 The action of reducing chatter by the cylindrical grinder as described above will be described below with reference to FIGS.
As shown in FIG. 4, the contact 103 of the unevenness detecting device 10 is always in contact with the lower part of the workpiece W of the workpiece W at the unevenness detection position where the angle from the grinding action point in the rotation direction of the workpiece is α degrees. To be arranged. The contact 113 of the workpiece pressing device 11 is always in contact with the workpiece at a workpiece pressing position opposite to the grinding action point of the workpiece W whose angle to the unevenness detection position is β degrees in the rotation direction of the workpiece. Placed in.
The unevenness detection device 10 detects a load change accompanying the unevenness change of chatter due to the rotation of the workpiece by the piezoelectric element 101 and outputs it to the voltage detector 12 as a voltage. At this time, the load fluctuation is proportional to the amplitude of chatter and becomes maximum at the apex of the convex part and becomes minimum at the concave part, and the voltage output similarly varies.

ビビリを低減するには、現在の研削作用点でのビビリの位相と周期と振幅を検出する必要がある。
図５に示すように、本実施例では凹凸検出装置１０による凹凸検出位置で検出した凹凸の周期と振幅を研削作用点でのビビリの周期と振幅とする。ビビリの周期Ｔは凹凸検出装置１０が検出する電圧変動の１周期の時間（秒）として検出する。ビビリの振幅は電圧出力変動幅に比例するので、あらかじめ定められた換算比率より、電圧変動幅を振幅に換算することで検出する。
位相については凹凸検出位置での位相と周期と工作物の回転速度から以下の方式で演算する。工作物Ｗと砥石車７の研削作用面の相対変位により研削点で生じた工作物Ｗのビビリは、工作物Ｗの回転により工作物押込み位置を通過しさらに凹凸検出位置に到達する。図６は、被加工部の円周面に生じたビビリの凸部を正、凹部を負として直線上に展開し、研削作用点、工作物押込み位置、凹凸検出位置の相対関係を表した図である。
図６において、研削作用点と凹凸検出位置の角度差αをビビリの周期を単位とする位相差Φ１で表し、工作物押込み位置と凹凸検出位置の角度差βをビビリの周期を単位とする位相差Φ２で表す。ビビリの周期をＴ（秒）、工作物の１秒当りの回転速度をＮ回転とすると、角度αの位相差Φ１はΦ１＝２π・α／（３６０・Ｎ・Ｔ）と表され、角度βの位相差Φ２はΦ２＝２π・β／（３６０・Ｎ・Ｔ）と表される。凹凸検出位置でのビビリの位相をω、振幅をａとすると、研削作用点でのビビリの位相はω−Φ１となり、工作物押込み位置でのビビリの位相はω−Φ２となる。研削作用点でのビビリの振幅変動はａ・ｓｉｎ（ω−Φ１）で表され、工作物押込み位置ではａ・ｓｉｎ（ω−Φ２）で表される。 In order to reduce chatter, it is necessary to detect the phase, period and amplitude of chatter at the current grinding action point.
As shown in FIG. 5, in this embodiment, the period and amplitude of the unevenness detected at the unevenness detection position by the unevenness detection device 10 are set as the chatter period and amplitude at the grinding action point. The chatter cycle T is detected as a time (second) of one cycle of voltage fluctuation detected by the unevenness detection device 10. Since the amplitude of chatter is proportional to the voltage output fluctuation range, it is detected by converting the voltage fluctuation range into amplitude from a predetermined conversion ratio.
The phase is calculated by the following method from the phase and period at the unevenness detection position and the rotational speed of the workpiece. The chattering of the workpiece W generated at the grinding point due to the relative displacement between the grinding surface of the workpiece W and the grinding wheel 7 passes through the workpiece pushing position by the rotation of the workpiece W, and further reaches the unevenness detection position. FIG. 6 is a diagram showing a relative relationship among a grinding action point, a workpiece pushing position, and a concavo-convex detection position developed on a straight line with the convex part of chatter generated on the circumferential surface of the work part being positive and the concave part being negative. It is.
In FIG. 6, the angle difference α between the grinding point and the unevenness detection position is represented by a phase difference Φ1 with the chatter period as a unit, and the angle difference β between the workpiece pushing position and the unevenness detection position with the chatter period as a unit. This is represented by a phase difference Φ2. If the chatter period is T (seconds) and the rotation speed of the workpiece is N rotations, the phase difference Φ1 of the angle α is expressed as Φ1 = 2π · α / (360 · N · T), and the angle β The phase difference Φ2 is expressed as Φ2 = 2π · β / (360 · N · T). When the chatter phase at the unevenness detection position is ω and the amplitude is a, the chatter phase at the grinding action point is ω−Φ1, and the chatter phase at the workpiece pushing position is ω−Φ2. The vibration fluctuation of the chatter at the grinding action point is represented by a · sin (ω−Φ1), and is represented by a · sin (ω−Φ2) at the workpiece pushing position.

工作物押付け装置１１の接触子１１３の工作物を砥石車７に近づける方向の作動を正とすると、ビビリを打ち消すために工作物に与える変位は、研削作用点での砥石車の研削作用面と工作物の相対変位と逆位相なので、ビビリと同位相であるａ・ｓｉｎ（ω−Φ１）となる。しかし研削においては、砥石研削点と工作物加工点間の研削盤各部に弾性変形が生じるため工作物の押込み作動分がそのまま実研削除去深さ変動とはならず、弾性変形分だけ少ない除去深さ変動となる、その補正をするため補正係数Ｋ１を用いる。接触子１１３の補正作動量ｄはｄ＝Ｋ１・ａ・ｓｉｎ（ω−Φ１）となる。
本実施例では研削作用点からの角度がα−βの位置で被加工部を押して工作物Ｗに変位を与える。この場合、被加工部が真円であれば前記の補正作動量ｄを工作物押付装置１１の接触子１１３の変位として与えればよい。しかし、ビビリにより被加工部には凹凸が発生しているので、工作物押付装置１１の接触子１１３を静止させている場合でも、工作物Ｗに凹凸の振幅に相当する変位が発生する。このため、工作物押込み位置のビビリの位相と逆位相の変位Ｋ１・ａ・ｓｉｎ（ω−Φ２＋π）を工作物押付装置１１の接触子１１３の作動量に加算して、被加工部のビビリの凹凸による押込み量の増減をキャンセルする必要がある。この加算は被加工部のビビリが大きいビビリ補正を開始してからα−βの角度工作物が回転するまで実施する。 If the operation of the contactor 113 of the workpiece pressing device 11 in the direction in which the workpiece is brought closer to the grinding wheel 7 is positive, the displacement given to the workpiece to cancel chatter is the grinding action surface of the grinding wheel at the grinding action point. Since it is in phase opposite to the relative displacement of the workpiece, a · sin (ω−Φ1), which is in phase with chatter. However, in grinding, elastic deformation occurs in each part of the grinder between the grinding wheel grinding point and the workpiece machining point, so that the pushing operation of the workpiece does not directly change the actual grinding removal depth, and the removal depth is reduced by the elastic deformation. A correction coefficient K1 is used to correct the fluctuation. The corrected operation amount d of the contactor 113 is d = K1 · a · sin (ω−Φ1).
In the present embodiment, the workpiece W is displaced by pushing the workpiece at a position where the angle from the grinding action point is α−β. In this case, if the workpiece is a perfect circle, the correction operation amount d may be given as the displacement of the contact 113 of the workpiece pressing device 11. However, since irregularities are generated in the workpiece due to chattering, a displacement corresponding to the amplitude of the irregularities is generated in the workpiece W even when the contactor 113 of the workpiece pressing device 11 is stationary. For this reason, the displacement K1 · a · sin (ω−Φ2 + π) having a phase opposite to the chattering phase at the workpiece pushing position is added to the operation amount of the contactor 113 of the workpiece pushing device 11, thereby It is necessary to cancel the increase / decrease in the pressing amount due to the unevenness. This addition is performed until the α-β angle workpiece rotates after chatter correction with large chatter of the workpiece is started.

以上より、最初に検出・演算されたΦ１、Φ２、ａ、ωをΦ１_１、Φ２_１、a_１、ω_１、とすると、１回目の補正データ式ｄ_１は補正を開始してからα−βの角度工作物が回転するまでは、ｄ_１＝Ｋ１・a_１・（ｓｉｎ（ω_１−Φ１_１）＋ｓｉｎ（ω_１−Φ２_１＋π））である。α−βの角度工作物が回転し、ビビリの低減された被加工面が工作物押込み位置に到達した後の補正データ式ｄ_１は、ｄ_１＝Ｋ１・ａ_１・ｓｉｎ（ω_１−Φ１_１）である。以上のデータ式ｄ_１により工作物の回転位置と対応したデータを作成し、このデータに基づき工作物押付け装置１１を作動させる。 From the above, assuming that Φ1, Φ2, a, and ω that are first detected and calculated are Φ1 ₁ , Φ2 ₁ , a ₁ , and ω ₁ , the first correction data equation d ₁ is α− Until the angle workpiece of β rotates, d ₁ = K1 · a ₁ · (sin (ω ₁ −Φ1 ₁ ) + sin (ω ₁ −Φ2 ₁ + π)). rotation angle workpiece alpha-beta, the correction data type d ₁ after reduced the processing surface of the chatter reaches the workpiece push-in position _{is, d 1 = K1 · a 1} · sin (ω 1 -Φ1 ₁ ). Create data corresponding with the rotational position of the workpiece by the data type d ₁ above, to operate the workpiece pressing device 11 on the basis of this data.

ビビリの低減が十分でなく２回目の補正を加える場合の補正データｄ_２は以下のように作成する。
被加工面のビビリは初回より小さくなっているので、被加工面のビビリの影響による押込み量の増減は無視して１回目の補正データｄ_０＝Ｋ１・a_１・ｓｉｎ（ω_１−Φ１_１）を工作物１回転分計算する。次に１回目の補正後に検出・演算したΦ１、ａ、ωをΦ１_２、a_２、ω_２、としｄ_ｓ＝Ｋ１・a_２・ｓｉｎ（ω_２−Φ１_２）を工作物１回転分計算する。ｄ_０、ｄ_ｓを工作物の回転位置と対応したデータとして保存し、工作物の回転位置毎にｄ_０とｄ_ｓを加算したデータをｄ_２とする。工作物回転位置θとω_１、ω_２、ｄ_１、ｄ_ｓの関係を図７に示す。 Correction data d ₂ when the reduction of chatter adds a second compensation not sufficient to create as follows.
Since the chatter of the work surface is smaller than the first time, the first correction data d ₀ = K1 · a ₁ · sin (ω ₁ −Φ1 ₁₎ is ignored, ignoring the increase / decrease of the indentation amount due to the chatter effect of the work surface. ) For one rotation of the workpiece. Next, Φ1, a and ω detected and calculated after the first correction are Φ1 ₂ , a ₂ and ω ₂ , and d _s = K1 · a ₂ · sin (ω ₂ −Φ1 ₂ ) is calculated for one rotation of the workpiece. To do. d ₀ and d _s are stored as data corresponding to the rotational position of the workpiece, and data obtained by adding d ₀ and d _s for each rotational position of the workpiece is defined as d ₂ . The relationship between the workpiece rotation position θ and ω ₁ , ω ₂ , d ₁ , d _s is shown in FIG.

本発明のビビリ低減動作を作動させるのは、研削サイクルにおける工作物回転当りの砥石車の切込み量が小さいときが効果的で、特に砥石車の切込みが停止しているスパークアウト研削時に作動させると効果が著しい。図８のフローチャートに基づきスパークアウトサイクルにおけるビビリ低減動作を説明する。
初めに主軸回転速度を検出することにより、主軸５に保持され回転している工作物Ｗの回転速度を検出する（ＳＴＰ１）。
次に、凹凸検出装置１０により工作物Ｗのビビリの周期Ｔ_１と振幅ａ_１を検出する（ＳＴＰ２）。周期Ｔ_１はビビリの凹凸による電圧増減の１周期の時間とし、振幅ａ_１は電圧変動幅と係数Ｋ２の積として算出する。係数Ｋ２は工作物回転速度や工作物の質量によりあらかじめ決定された値をデータとして入力しておく。
位相差Φ１とΦ２を、Φ１_１＝２π・α／（３６０・Ｎ・Ｔ_１）、Φ２_１＝２π・β／（３６０・Ｎ・Ｔ_１）として演算する（ＳＴＰ３）。
工作物押付け装置１１の駆動データｄ_１を作成する、ω_１がΦ１−Φ２の間はｄ_１＝Ｋ１・a_１・（ｓｉｎ（ω_１−Φ１_１）＋ｓｉｎ（ω_１−Φ２_１＋π））とし、ω_１がΦ１−Φ２以降についてはｄ_１＝Ｋ１・a_１・ｓｉｎ（ω_１−Φ１_１）とする。ビビリの位相ω_１を工作物回転角度θに換算し、ｄ_１と工作物回転角度θを対応させた駆動データ表に保存する（ＳＴＰ４）。ここで、スタート位置はω_１＝０、θ＝０とする。 The chatter reduction operation of the present invention is effective when the cutting amount of the grinding wheel per work rotation in the grinding cycle is small, particularly when it is operated during spark-out grinding when the cutting of the grinding wheel is stopped. The effect is remarkable. The chatter reduction operation in the spark-out cycle will be described based on the flowchart of FIG.
First, by detecting the spindle rotational speed, the rotational speed of the workpiece W held and rotating by the spindle 5 is detected (STP1).
Next, detecting the period _{T 1} and an amplitude _{a 1} of chatter of the workpiece W by the unevenness detecting device 10 (STP2). Period T ₁ is a time of one cycle of the voltage decrease due to the unevenness of the chatter, the amplitude a ₁ is calculated as the product of the voltage fluctuation range and the coefficient K2. As the coefficient K2, a value determined in advance by the workpiece rotational speed and the workpiece mass is input as data.
The phase differences Φ1 and Φ2 are calculated as Φ1 ₁ = 2π · α / (360 · N · T ₁ ) and Φ2 ₁ = 2π · β / (360 · N · T ₁ ) (STP3).
Drive data d ₁ of the workpiece pressing device 11 is created. When ω ₁ is Φ1−Φ2, d ₁ = K1 · a ₁ · (sin (ω ₁ −Φ1 ₁ ) + sin (ω ₁ −Φ2 ₁ + π)) When ω ₁ is Φ1−Φ2 and thereafter, d ₁ = K1 · a ₁ · sin (ω ₁ −Φ1 ₁ ). The chatter phase ω ₁ is converted into a workpiece rotation angle θ and stored in a drive data table in which d ₁ and the workpiece rotation angle θ are associated with each other (STP4). Here, the start positions are ω ₁ = 0 and θ = 0.

凹凸検出装置１０により位相ω_１＝０を検出する（ＳＴＰ５）。
ω_１＝ｎ・２・π（ｎは整数）の工作物回転位置をスタート位置として駆動データ表の工作物回転に基づいた変位ｄ_１によって工作物押付け装置１１を駆動しながら、工作物を１回転させる（ＳＴＰ６）。
ビビリ補正開始後に工作物がα以上回転した後の、ビビリ振幅a_２を検出する（ＳＴＰ７）。
ビビリ振幅a_２が目標値以下かを判定する（ＳＴＰ８）。
ビビリ振幅a_２が目標値より大きければ、ビビリ周期Ｔ_２とビビリ振幅a_２とθ＝０におけるω_２の位相ω_２０を検出する（ＳＴＰ９）。
位相差Φ１をΦ１_２＝２π・α／（３６０・Ｎ・Ｔ_２）として演算する（ＳＴＰ１０）。
ｄ_１＝Ｋ１・a_１・ｓｉｎ（ω_１−Φ１_１）、ｄ_ｓ＝Ｋ１・a_２・ｓｉｎ（ω_２−Φ１_２）とする。ビビリの位相ω_１、ω_２を工作物回転角度θに換算し、同一の工作物回転角度θに対応したｄ_１とｄ_ｓの値を加算し補正データｄ_２とし、駆動データ表に保存する（ＳＴＰ１１）。
研削点の工作物回転角度θが０の位置で２回目の補正データｄ_２に基づいた工作物押付け装置１１の駆動をスタートし、工作物を１回転させる（ＳＴＰ６）。
以下（ＳＴＰ７）、（ＳＴＰ８）を実行し、ビビリ振幅が目標値以下となったら砥石台３を後退させて研削を終了する（ＳＴＰ１２）。 The unevenness detecting device 10 detects the phase ω ₁ = 0 (STP5).
While the workpiece pressing device 11 is driven by the displacement d ₁ based on the workpiece rotation in the drive data table with the workpiece rotation position of ω ₁ = n · 2 · π (n is an integer) as the start position, the workpiece is moved to 1 Rotate (STP6).
After the workpiece after chatter correction start is rotated above alpha, it detects a chatter amplitude a ₂ (STP7).
Determining chatter amplitude _{a 2} is whether the target value or less (STP8).
If chatter amplitude a ₂ is larger than the target value, chatter cycle T ₂ , chatter amplitude a ₂ and phase ω ₂₀ of ω _{2 at} θ = 0 are detected (STP 9).
The phase difference Φ1 is calculated as Φ1 ₂ = 2π · α / (360 · N · T ₂ ) (STP10).
It is assumed that d ₁ = K1 · a ₁ · sin (ω ₁ −Φ1 ₁ ) and d _s = K1 · a ₂ · sin (ω ₂ −Φ1 ₂ ). The chatter phases ω ₁ and ω ₂ are converted into the workpiece rotation angle θ, and the values of d ₁ and d _s corresponding to the same workpiece rotation angle θ are added to obtain correction data d ₂ and stored in the drive data table. (STP11).
When the workpiece rotation angle θ at the grinding point is 0, the driving of the workpiece pressing device 11 based on the _second correction data d2 is started, and the workpiece is rotated once (STP6).
Thereafter, (STP7) and (STP8) are executed, and when the chatter amplitude becomes equal to or smaller than the target value, the grindstone table 3 is moved backward to finish grinding (STP12).

＜第２の実施形態＞
第１の実施形態ではビビリ周期を被加工部のビビリの凹凸の１周期を検出することで検出したが、ビビリ発生の大部分の原因は砥石車７の研削作用面の回転に伴う変位の変動なので、砥石回転周期をビビリ周期としてビビリの位相を算出してもよい。
図９に示すように、本実施例では凹凸検出装置１０による凹凸検出位置で検出した凹凸の振幅を研削作用点でのビビリの振幅とする。ビビリの周期Ｔとして砥石車回転速度検出手段３５にて砥石車７が１回転する時間（秒）を検出する。なお、砥石車回転速度検出手段３５としては、砥石軸に回転速度センサを取り付けることにより実現することができるし、実測値によらず砥石軸回転モータへの指令値を用いることも可能である。
研削作用点での位相は、凹凸検出位置でのビビリの位相と砥石車７の回転周期と工作物の回転速度を用いて、第１の実施形態と同様に演算する。
ビビリ低減動作についても第１の実施形態と同様に実施する。 <Second Embodiment>
In the first embodiment, the chatter cycle is detected by detecting one cycle of the chatter unevenness of the workpiece, but most of the chattering is caused by a change in displacement due to rotation of the grinding surface of the grinding wheel 7. Therefore, the chatter phase may be calculated using the grindstone rotation cycle as the chatter cycle.
As shown in FIG. 9, in this embodiment, the amplitude of the unevenness detected at the unevenness detection position by the unevenness detection device 10 is set as the amplitude of chatter at the grinding action point. As the chatter cycle T, the grinding wheel rotational speed detection means 35 detects the time (seconds) that the grinding wheel 7 makes one rotation. The grinding wheel rotational speed detection means 35 can be realized by attaching a rotational speed sensor to the grinding wheel shaft, or a command value to the grinding wheel shaft rotation motor can be used regardless of the actual measurement value.
The phase at the grinding action point is calculated in the same manner as in the first embodiment, using the chatter phase at the unevenness detection position, the rotation cycle of the grinding wheel 7 and the rotation speed of the workpiece.
The chatter reduction operation is also performed in the same manner as in the first embodiment.

＜第３の実施形態＞
砥石車７の研削作用面の回転に伴う半径位置が変動する場合は砥石台３を振動させるので、その振動周期をビビリ周期としてビビリの位相を算出してもよい。
図１０に示すように、本実施例では凹凸検出装置１０による凹凸検出位置で検出した凹凸の振幅を研削作用点でのビビリの振幅とする。ビビリの周期Ｔとして砥石台振動周期検出手段３６にて砥石台３の砥石車７の切込み方向の振動の周期（秒）を検出する。なお、砥石台振動周期検出手段３６としては、砥石台３に振動センサを取り付けることにより実現することができる。
研削作用点での位相は、凹凸検出位置でのビビリの位相と砥石台３の振動周期と工作物の回転速度を用いて、第１の実施形態と同様に演算する。
ビビリ低減動作についても第１の実施形態と同様に実施する。 <Third Embodiment>
Since the grinding wheel base 3 is vibrated when the radial position varies with the rotation of the grinding surface of the grinding wheel 7, the chatter phase may be calculated using the vibration cycle as the chatter cycle.
As shown in FIG. 10, in this embodiment, the amplitude of the unevenness detected at the unevenness detection position by the unevenness detecting device 10 is set as the amplitude of chattering at the grinding action point. As the chatter cycle T, the grindstone vibration cycle detecting means 36 detects the vibration cycle (second) in the cutting direction of the grinding wheel 7 of the grindstone table 3. The grindstone vibration period detecting means 36 can be realized by attaching a vibration sensor to the grindstone table 3.
The phase at the grinding action point is calculated in the same manner as in the first embodiment, using the chattering phase at the unevenness detection position, the vibration cycle of the grinding wheel table 3, and the rotational speed of the workpiece.
The chatter reduction operation is also performed in the same manner as in the first embodiment.

＜第４の実施形態＞
図１１に示すように、本実施例では凹凸検出装置１０による凹凸検出位置で検出した凹凸の振幅を研削作用点でのビビリの振幅とする。ビビリの周期Ｔとして砥石台振動周期検出手段３６にて砥石台３の砥石車７の切込み方向の振動の周期（秒）を検出する。ビビリの研削作用点での位相は、砥石台振動位相検出手段３７にて砥石台３の砥石車７の切込み方向の振動の砥石台後退方向を正とした位相で検出する。なお、砥石台振動位相検出手段３７としては、砥石台３に振動センサを取り付けることにより実現することができ、砥石台振動周期検出手段３６の振動センサと兼ねることも可能である。
ビビリ低減動作についても第１の実施形態と同様に実施する。 <Fourth Embodiment>
As shown in FIG. 11, in this embodiment, the amplitude of the unevenness detected at the unevenness detection position by the unevenness detection device 10 is set as the amplitude of chatter at the grinding action point. As the chatter cycle T, the grindstone vibration cycle detecting means 36 detects the vibration cycle (second) in the cutting direction of the grinding wheel 7 of the grindstone table 3. The phase at the grinding action point of chattering is detected by the grinding wheel base vibration phase detecting means 37 with a phase in which the grinding wheel head retreating direction of the grinding wheel 7 in the cutting direction of the grinding wheel base 3 is positive. The grinding wheel base vibration phase detection means 37 can be realized by attaching a vibration sensor to the grinding wheel base 3 and can also serve as the vibration sensor of the grinding wheel base vibration period detection means 36.
The chatter reduction operation is also performed in the same manner as in the first embodiment.

＜第１〜第４の実施形態の変形態様＞
第１〜第４の実施形態では工作物Ｗの被加工部を押すことで工作物を変位させたが、工作物を保持する主軸台と心押し台に変位手段を備えても良い、この場合の補正変位ｄはｄ＝Ｋ１・ａ・ｓｉｎ（ω−Φ１）とする。
第１〜第４の実施形態ではビビリの振幅ａを圧電素子１０１の電圧変動で検出したが、変位計で被加工部の半径変動を検出してビビリ振幅ａとしてもよい。
第１〜第４の実施形態では工作物Ｗと砥石車７の相対位置の制御に工作物Ｗを変位させたが、砥石車を変位させてもよい。砥石車を変位させるには、例えば、砥石車の静圧軸受けの砥石切込み方向の静圧ポケット部の圧力を変動させることで可能である。 <Modification of First to Fourth Embodiments>
In the first to fourth embodiments, the workpiece is displaced by pushing the workpiece of the workpiece W. However, in this case, the headstock and the tailstock that hold the workpiece may be provided with a displacement means. The corrected displacement d is d = K1 · a · sin (ω−Φ1).
In the first to fourth embodiments, the chatter amplitude a is detected by the voltage fluctuation of the piezoelectric element 101, but the radius fluctuation of the workpiece may be detected by a displacement meter to obtain the chatter amplitude a.
In the first to fourth embodiments, the workpiece W is displaced to control the relative position between the workpiece W and the grinding wheel 7, but the grinding wheel may be displaced. In order to displace the grinding wheel, for example, it is possible to vary the pressure of the static pressure pocket portion in the grinding wheel cutting direction of the static pressure bearing of the grinding wheel.

１：円筒研削盤３：砥石台Ｗ：工作物５：主軸６：心押台７：砥石車８：砥石軸１０：凹凸検出装置１１：工作物押付け装置１１１：圧電素子３３：研削作用点ビビリ検出手段３５：砥石車回転速度検出手段３６：砥石台振動周期検出手段３７：砥石台振動位相検出手段３２１：主軸速度検出手段 1: Cylindrical grinding machine 3: Grinding wheel base W: Work piece 5: Main shaft 6: Tailstock 7: Grinding wheel 8: Grinding wheel shaft 10: Concavity and convexity detection device 11: Workpiece pressing device 111: Piezoelectric element 33: Grinding action point chatter Detection means 35: Grinding wheel rotational speed detection means 36: Wheel head vibration period detection means 37: Wheel head vibration phase detection means 321: Spindle speed detection means

Claims

円筒状の工作物を支持して回転駆動させる工作物支持手段と、
砥石車を支持し回転駆動させる砥石車支持手段と、
前記工作物支持手段と前記砥石車支持手段とを相対移動させ、前記砥石車で前記工作物を研削する駆動手段と、
前記工作物の研削に伴い前記工作物の被加工部に生じる円周方向に分布する理想形状に対する凹凸であるビビリの研削作用点での位相を検出する位相検出手段と、
前記工作物と前記砥石車の相対変位を、前記研削作用点での前記ビビリの位相から判定した前記工作物と前記砥石車の相対変位の位相と、逆位相に変位させる相対位置制御手段と、
を備える円筒研削盤。 A workpiece support means for supporting and rotating the cylindrical workpiece;
A grinding wheel support means for supporting and rotating the grinding wheel;
Driving means for relatively moving the workpiece support means and the grinding wheel support means and grinding the workpiece with the grinding wheel;
Phase detection means for detecting a phase at a grinding action point of chattering that is unevenness with respect to an ideal shape distributed in a circumferential direction generated in a workpiece portion of the workpiece as the workpiece is ground;
A relative position control means for displacing the relative displacement between the workpiece and the grinding wheel from the phase of the chatter at the grinding action point and the phase of the relative displacement between the workpiece and the grinding wheel;
A cylindrical grinding machine.

前記被加工部の前記ビビリの振幅を検出するビビリ振幅検出手段を備え、前記相対位置制御手段を前記ビビリの振幅に比例した作動量で作動させる請求項１記載の円筒研削盤。 The cylindrical grinding machine according to claim 1, further comprising a chatter amplitude detecting unit that detects the chatter amplitude of the workpiece, and operating the relative position control unit with an operation amount proportional to the chatter amplitude.

前記被加工部の前記ビビリの振幅が所定の値より小さくなったときに研削を終了する請求項２記載の円筒研削盤。 The cylindrical grinding machine according to claim 2, wherein the grinding is finished when an amplitude of the chatter of the workpiece becomes smaller than a predetermined value.

前記位相検出手段を
被加工部の前記ビビリの周期を検出するビビリ周期検出手段と、
前記工作物の外周の所定の円周方向位置である測定点での前記ビビリの位相を検出する測定点位相検出手段と、
前記工作物の回転速度を検出する回転速度検出手段と、
前記ビビリ周期検出手段により検出された前記ビビリの周期と前記測定点位相検出手段により検出されたビビリの位相と、前記回転速度検出手段にて検出された前記工作物の回転速度と、から前記工作物の前記研削作用点での前記ビビリの位相を算出するビビリ演算手段と、
で構成する請求項１〜請求項３のいずれか１項に記載の円筒研削盤。 The chatter cycle detection unit that detects the chatter cycle of the workpiece, the phase detection unit;
Measurement point phase detection means for detecting the phase of the chatter at a measurement point which is a predetermined circumferential position on the outer periphery of the workpiece;
Rotation speed detection means for detecting the rotation speed of the workpiece;
From the chatter cycle detected by the chatter cycle detector, the chatter phase detected by the measurement point phase detector, and the rotational speed of the workpiece detected by the rotational speed detector, the workpiece A chatter calculating means for calculating a phase of the chatter at the grinding action point of the object;
The cylindrical grinding machine of any one of Claims 1-3 comprised by these.

前記位相検出手段を
前記砥石車の回転周期を検出する砥石車回転周期検出手段と、
前記工作物の外周の所定の円周方向位置である測定点での前記ビビリの位相を検出する前記測定点位相検出手段と、
前記工作物の回転速度を検出する回転速度検出手段と、
前記砥石車回転周期検出手段により検出された前記砥石車の回転周期と、前記測定点位相検出手段により検出されたビビリの位相と、前記回転速度検出手段にて検出された前記工作物の回転速度と、から前記工作物の前記研削作用点での前記ビビリの位相を算出するビビリ演算手段と、
で構成する請求項１〜請求項３のいずれか１項に記載の円筒研削盤。 Grinding wheel rotation period detection means for detecting the rotation period of the grinding wheel;
The measurement point phase detection means for detecting the phase of the chatter at a measurement point which is a predetermined circumferential position on the outer periphery of the workpiece;
Rotation speed detection means for detecting the rotation speed of the workpiece;
The rotation cycle of the grinding wheel detected by the grinding wheel rotation cycle detection means, the chatter phase detected by the measurement point phase detection means, and the rotation speed of the workpiece detected by the rotation speed detection means And a chatter calculating means for calculating a phase of the chatter at the grinding action point of the workpiece from
The cylindrical grinding machine of any one of Claims 1-3 comprised by these.

前記位相検出手段を
前記砥石車支持手段の振動周期を検出する砥石振動周期検出手段と、
前記工作物の外周の所定の円周方向位置である測定点での前記ビビリの位相を検出する測定点位相検出手段と、
前記工作物の回転速度を検出する回転速度検出手段と、
前記砥石振動周期検出手段により検出された前記砥石車支持手段の振動周期と、前記測定点位相検出手段により検出されたビビリの位相と、前記回転速度検出手段にて検出された前記工作物の回転速度と、から前記工作物の前記研削作用点での前記ビビリの位相を算出するビビリ演算手段と、
で構成する、請求項１〜請求項３のいずれか１項に記載の円筒研削盤。 Grinding wheel vibration period detecting means for detecting the vibration period of the grinding wheel support means, the phase detection means,
Measurement point phase detection means for detecting the phase of the chatter at a measurement point which is a predetermined circumferential position on the outer periphery of the workpiece;
Rotation speed detection means for detecting the rotation speed of the workpiece;
The vibration cycle of the grinding wheel support means detected by the grinding wheel vibration period detection means, the chatter phase detected by the measurement point phase detection means, and the rotation of the workpiece detected by the rotation speed detection means A chatter calculating means for calculating the chatter phase at the grinding action point of the workpiece from the speed;
The cylindrical grinding machine of any one of Claims 1-3 comprised by these.

前記位相検出手段を前記砥石車支持手段の前記砥石車の前記工作物切込み方向の振動位相を検出する砥石振動位相検出手段で構成する、請求項１〜請求項３のいずれか１項に記載の円筒研削盤。 The said phase detection means is comprised with the grindstone vibration phase detection means which detects the vibration phase of the said workpiece cutting direction of the said grinding wheel of the said grinding wheel support means, The any one of Claims 1-3. Cylindrical grinding machine.

前記相対位置制御手段を前記工作物を変位させる工作物変位手段で構成する請求項１〜請求項７のいずれか１項に記載の円筒研削盤。 The cylindrical grinding machine according to any one of claims 1 to 7, wherein the relative position control means is constituted by a workpiece displacement means for displacing the workpiece.

前記工作物変位手段を前記工作物の研削作用点と１８０度位相がずれた位置で前記工作物の被加工部に接触して押圧する工作物押付け装置で構成し、
前記工作物押付け装置を、前記研削作用点での前記ビビリの位相から判定した前記工作物と前記砥石車の相対変位の位相と逆位相に変位させるような変位量から、前記工作物押付け装置が接触する前記工作物の被加工部における前記ビビリの凹凸高さを差し引いた値で制御する、請求項８記載の円筒研削盤。 The workpiece displacing means comprises a workpiece pressing device that contacts and presses the workpiece to be processed at a position 180 degrees out of phase with the grinding point of the workpiece;
From the amount of displacement that causes the workpiece pressing device to be displaced in a phase opposite to the phase of relative displacement between the workpiece and the grinding wheel determined from the chatter phase at the grinding action point, the workpiece pressing device is The cylindrical grinding machine according to claim 8, wherein the cylindrical grinder is controlled by a value obtained by subtracting the uneven height of the chattering in a workpiece portion of the workpiece to be contacted.

前記相対位置制御手段の駆動に圧電素子を用いる請求項９記載の円筒研削盤。 The cylindrical grinding machine according to claim 9, wherein a piezoelectric element is used to drive the relative position control means.

前記ビビリ周期検出手段を前記被加工部の凹凸を検知する凹凸検知手段により前記凹凸の周期を検出することで構成する請求項４記載の円筒研削盤。 The cylindrical grinding machine according to claim 4, wherein the chatter cycle detecting unit is configured to detect a cycle of the unevenness by an unevenness detecting unit that detects the unevenness of the workpiece.

前記ビビリ振幅検出手段を前記被加工部の凹凸を検知する凹凸検知手段により前記凹凸の振幅を検出することで構成する、請求項２〜請求項６のいずれか１項に記載の円筒研削盤。 The cylindrical grinder according to any one of claims 2 to 6, wherein the chatter amplitude detecting means is configured by detecting the amplitude of the unevenness by an unevenness detecting means for detecting unevenness of the workpiece.

前記測定点位相検出手段を前記被加工部の凹凸を検知する凹凸検知手段により前記凹凸の位相を検出することで構成する、請求項４〜請求項６のいずれか１項に記載の円筒研削盤。 The cylindrical grinding machine according to any one of claims 4 to 6, wherein the measurement point phase detection unit is configured to detect a phase of the unevenness by an unevenness detection unit that detects unevenness of the workpiece. .

前記凹凸検出手段と被加工部の下部が接触するように配置する請求項１１〜請求項１３のいずれか１項に記載の円筒研削盤。 The cylindrical grinder according to any one of claims 11 to 13, wherein the cylindrical grinder is disposed so that the unevenness detecting means and a lower portion of the workpiece are in contact with each other.