JPH0224529A - Method for measuring accuracy in non-repeating rotation of bearing - Google Patents
Method for measuring accuracy in non-repeating rotation of bearingInfo
- Publication number
- JPH0224529A JPH0224529A JP17592788A JP17592788A JPH0224529A JP H0224529 A JPH0224529 A JP H0224529A JP 17592788 A JP17592788 A JP 17592788A JP 17592788 A JP17592788 A JP 17592788A JP H0224529 A JPH0224529 A JP H0224529A
- Authority
- JP
- Japan
- Prior art keywords
- bearing
- inner ring
- rotated
- outer ring
- main 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 8
- 238000006073 displacement reaction Methods 0.000 claims abstract description 35
- 230000003252 repetitive effect Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 238000001454 recorded image Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
Landscapes
- Mounting Of Bearings Or Others (AREA)
- Length Measuring Devices With Unspecified Measuring Means (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、軸受の回転精度の測定方法に関し、特に玉
軸受の非繰返し回転精度の測定方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for measuring the rotational accuracy of a bearing, and particularly to a method for measuring the non-repetitive rotational accuracy of a ball bearing.
磁気ディスク装置等において、ディスクに書き込まれた
情報を読み取る場合、ディスク装置の回転軸の１回転目
と２回転目の回転のずれの精度、即ち非繰返し精度が読
み取り精度に直接影響を及ぼす。このため、玉軸受の非
繰返し精度に対する要求レベルは、磁気ディスク装置等
の発展に伴い、近年急速に厳しくなっている。When reading information written on a disk in a magnetic disk device or the like, the accuracy of the rotational deviation between the first and second rotations of the rotating shaft of the disk device, that is, the non-repeatability, directly affects the reading accuracy. For this reason, the required level of non-repeatability of ball bearings has rapidly become stricter in recent years with the development of magnetic disk drives and the like.
従来の非繰返し精度の測定方法は、第８図に示すように
、玉軸受１の外輪２を装置本体３の一部に固定し、内輪
４を主軸５に嵌合し、主軸５を空気軸受６により支持す
ると共に、主軸５の外周の一定位置において装置本体３
に取付けた変位センサー７により、主軸５のラジアル方
向の振れを検出する。変位センサー７の検出信号は、適
宜な処理を加えたうえでＦＦＴ（高速フーリエ変換）分
析器に入力され、分析記録される。As shown in FIG. 8, the conventional method for measuring non-repeatability is to fix the outer ring 2 of the ball bearing 1 to a part of the device body 3, fit the inner ring 4 to the main shaft 5, and connect the main shaft 5 to an air bearing. 6 and at a certain position on the outer periphery of the main shaft 5.
The deflection of the main shaft 5 in the radial direction is detected by a displacement sensor 7 attached to the main shaft 5. The detection signal from the displacement sensor 7 is subjected to appropriate processing and then input to an FFT (fast Fourier transform) analyzer, where it is analyzed and recorded.
上記のように、従来の測定方法は、外輪２及び変位セン
サー７を固定し、内輪４のみを主軸５により高速回転さ
せて非繰返し精度を測定するものであった。As described above, in the conventional measurement method, the outer ring 2 and the displacement sensor 7 are fixed, and only the inner ring 4 is rotated at high speed by the main shaft 5 to measure non-repeatable accuracy.
しかしながら、このような測定方法は、非繰返し精度を
精度よく測定するものであるということはできない。However, such a measurement method cannot be said to accurately measure non-repeatability.
即ち、第９図は外輪に形状不良のある玉軸受について、
外輪を固定するとともに内輪を高速回転し、変位センサ
ーの位置を主軸のまわりにおいて４５°づつ変えて非繰
返し精度を測定し、その精度に占める保持器成分、内輪
成分、外輪成分、及びボール成分の割合をグラフに示し
たものである。In other words, Fig. 9 shows a ball bearing with a defective outer ring.
While the outer ring is fixed, the inner ring is rotated at high speed, and the position of the displacement sensor is changed around the main shaft in 45° increments to measure non-repeatable accuracy. The ratio is shown in a graph.
この図かられかるように、変位センサーの位置によって
非繰返し精度の測定精度に差があることがわかる。As can be seen from this figure, there is a difference in the non-repeatability measurement accuracy depending on the position of the displacement sensor.
このため、例えば９０°の位置で測定した数値（回の場
合、約０．１８ｎ）を基準値に定めた場合、実際の使用
においてはそれより大きい振れ（例えばθ°の位置にお
いて約０．２９ｍ）が現れ、基準値を満足しない事態が
生じ得る。For this reason, for example, if the value measured at the 90° position (approximately 0.18n in the case of rotation) is set as the reference value, in actual use the runout will be larger than that (for example, approximately 0.29m at the θ° position). ) may appear and a situation may occur where the standard value is not satisfied.
そこで、この発明は、軸受の全周囲において測定するこ
とにより非繰返し精度の最大値が得られる測定方法を提
供することを目的とする。Therefore, it is an object of the present invention to provide a measuring method that can obtain the maximum value of non-repeatable accuracy by measuring around the entire circumference of a bearing.
上記の目的を達成するために、この発明の第一の手段は
、軸受の内輪と外輪のいずれか一方を高速回転軸と一体
化するとともに、他方を低速回転軸と一体化し、上記高
速回転軸に接近して配置した変位計の変位センサーを装
置の固定部分に支持せしめ、両方の回転軸を回転させな
がら変位針の出力信号を記録するようにしたものである
。In order to achieve the above object, a first means of the present invention is to integrate one of the inner ring and the outer ring of the bearing with the high-speed rotating shaft, and to integrate the other with the low-speed rotating shaft, so that the high-speed rotating shaft A displacement sensor of a displacement meter placed close to the needle is supported by a fixed part of the device, and the output signal of the displacement needle is recorded while rotating both rotating shafts.
また、第二の手段は、軸受の内輪と外輪のいずれか一方
を高速回転軸と一体化するとともに、他方を装置の固定
部分に支持せしめ、上記高速回転軸に接近して設置した
変位計の変位センサーを高速回転軸と同軸で低速回転さ
せながら変位計の出力信号を記録するようにしたもので
ある。The second method is to integrate either the inner ring or the outer ring of the bearing with the high-speed rotating shaft, support the other on a fixed part of the device, and use a displacement meter installed close to the high-speed rotating shaft. The output signal of the displacement meter is recorded while the displacement sensor is rotated at low speed coaxially with the high-speed rotating shaft.
第１図及び第２図は前記第一の手段を実施する測定装置
の一例を示すものである。FIGS. 1 and 2 show an example of a measuring device implementing the first means.
測定対象となる玉軸受１ｏの外輪１）は軸受箱１２に保
持され、その内輪１３は主軸１４に嵌着される。主軸１
４は固定部材１５を貫通し・空気軸受１６により回転に
支持され、その下端に従動ブー１月７が取付けられる。An outer ring 1) of a ball bearing 1o to be measured is held in a bearing box 12, and an inner ring 13 thereof is fitted onto a main shaft 14. Main shaft 1
4 passes through the fixed member 15 and is rotatably supported by an air bearing 16, and a driven boot 7 is attached to its lower end.
この従動プーリ１７は、ベルト１８を通じて高速回転す
るモータ（図示省略）により回転される。This driven pulley 17 is rotated by a motor (not shown) that rotates at high speed through a belt 18.
上記の固定部材１５のまわりに軸受１９を介して円筒状
の従動ブーＩＪ ２０が嵌合される。従動ブーＩＪ２０
はベルト２１通して低速回転のモータ２２により回転さ
れる。前記の軸受箱１２は、この従動プーリ２０の上端
に支持される。A cylindrical driven boob IJ 20 is fitted around the fixed member 15 via a bearing 19. Driven boo IJ20
is rotated by a low speed motor 22 through a belt 21. The bearing box 12 is supported on the upper end of the driven pulley 20.
主軸１４を通じて高速回転されると内輪１３と、軸受箱
１２を通じて同一方向に低速回転される外輪１）との回
転速度の比は、１０対１以上である。The rotational speed ratio between the inner ring 13, which is rotated at high speed through the main shaft 14, and the outer ring 1), which is rotated at low speed in the same direction through the bearing box 12, is 10:1 or more.
なお、内輪１３と外輪１）とは、互いに逆方向の回転で
もよい。Note that the inner ring 13 and the outer ring 1) may rotate in opposite directions.
主軸１４の突出端に接近してそのまわりの一定位置にお
いて、変位センサー２３が配置される。A displacement sensor 23 is arranged at a fixed position close to and around the protruding end of the main shaft 14 .
この変位センサー２３は装置本体２４に固定される。This displacement sensor 23 is fixed to the device main body 24.
変位センサー２３の検出信号は、変位計２５を通シてフ
ィルター２６に入力される。フィルター２６において回
転周波数成分が抑制された信号は、ＦＦＴ分析器２７に
入力される。ＦＦＴ分析器２７は、入力された信号を所
要回転数分（例えば６０回転分）記憶する。記憶される
信号の位相は、主軸１４の回転計２８から得られる回転
信号により調整される。なお、図中２９は、主軸１４に
付設した回転センサーである。A detection signal from the displacement sensor 23 is input to a filter 26 through a displacement meter 25. The signal whose rotational frequency components have been suppressed by the filter 26 is input to the FFT analyzer 27 . The FFT analyzer 27 stores the input signal for the required number of revolutions (for example, 60 revolutions). The phase of the stored signal is adjusted by the rotation signal obtained from the tachometer 28 of the main shaft 14. Note that 29 in the figure is a rotation sensor attached to the main shaft 14.
ＦＦＴ分析器２７において記憶された信号を、位相を合
せて記録紙に重ね書きすると、第３図に示すごとき記録
図が得られる。この図からも最も乱れ幅の大きい位置で
の振れ幅δを非繰返し精度の最大値として読み取る。When the signals stored in the FFT analyzer 27 are overwritten on recording paper with their phases aligned, a recording diagram as shown in FIG. 3 is obtained. From this figure, the amplitude δ at the position where the disturbance width is the largest can be read as the maximum value of non-repeatability.
第４図及び第５図は、前記第一の手段を実施する他の測
定装置の例を示すものである。この測定′！Ａ置は、前
記の場合と同様に変位センサー２３を固定して測定する
ものであるが、前記の場合と逆に測定対象となる玉軸受
１０の外輪１）を高速回転し、内輪１３を低速回転する
ようになっている。FIGS. 4 and 5 show examples of other measuring devices implementing the first means. This measurement′! In position A, the displacement sensor 23 is fixed and measured as in the previous case, but contrary to the above case, the outer ring 1) of the ball bearing 10 to be measured is rotated at high speed, and the inner ring 13 is rotated at low speed. It is designed to rotate.
即ち、測定対象となる玉軸受１０の外輪１）を主軸１４
の上端においてゴムなどの弾性体３１を介在して支持す
る。主軸１４の支持構造は前述のものと同様である。That is, the outer ring 1) of the ball bearing 10 to be measured is connected to the main shaft 14.
An elastic body 31 such as rubber is interposed to support the upper end. The support structure for the main shaft 14 is similar to that described above.
主軸１４の上方に装置本体２４に固定したアーム３２を
設け、そのアーム３２に主軸１４と同芯状態の内輪回転
軸３３を支持し、モータ３４により低速回転させる。内
輪回転軸３３の下端には玉軸受１０の内輪１３が嵌着さ
れる。変位センサー２３は、外輪１）の外周の一定位置
において非接触状態に配置され、装置本体２４に固定さ
れる。An arm 32 fixed to the device main body 24 is provided above the main shaft 14, and an inner ring rotating shaft 33 coaxial with the main shaft 14 is supported on the arm 32 and rotated at low speed by a motor 34. The inner ring 13 of the ball bearing 10 is fitted to the lower end of the inner ring rotating shaft 33. The displacement sensor 23 is arranged in a non-contact manner at a fixed position on the outer circumference of the outer ring 1) and is fixed to the device main body 24.
なお、この場合も、第１図の場合と同様の変位計２５、
フィルター２６、ＦＦＴ分析器２７、回転計２８及び回
転センサー２９が設けられるが、図示を省略している。In addition, in this case as well, the same displacement gauge 25 as in the case of FIG.
Although a filter 26, an FFT analyzer 27, a rotation meter 28, and a rotation sensor 29 are provided, illustration thereof is omitted.
上記の装置において、主軸１４を高速回転し、内輪回転
軸３３をｌＯ対１以上の比で低速回転して、前記と同様
に非繰返し精度を測定する。この場合も、第３図と同様
の記録図が得られる。In the above apparatus, the main shaft 14 is rotated at high speed, the inner ring rotating shaft 33 is rotated at low speed at a ratio of lO to 1 or more, and the non-repeatability is measured in the same manner as described above. In this case as well, a recorded image similar to that shown in FIG. 3 is obtained.
以上ｂｉいずれも変位センサー２３を固定し・内輪１３
又は外輪１）のいずれか一方を高速回転し、他方を低速
回転するようにしたものであったが、この発明の第二の
手段は、第６図に示すように測定対象の玉軸受１０の内
輪１３を高速回転させ、外輪１）を固定し、変位センサ
ー２３を低速回転するものである。この場合の内輪１３
は第１図に示すごとき主軸１４により回転される。また
、外輪１）は、第１図における軸受箱１２を装置本体２
４に固定することにより固定される。変位センサー２３
は、装置本体２４上に主軸１４と同芯状態に設けた低速
回転のターンテーブルに支持される。In both cases, the displacement sensor 23 is fixed and the inner ring 13 is
Alternatively, one of the outer rings 1) is rotated at high speed and the other is rotated at low speed. However, the second means of the present invention is to rotate the ball bearing 10 to be measured as shown in FIG. The inner ring 13 is rotated at high speed, the outer ring 1) is fixed, and the displacement sensor 23 is rotated at low speed. Inner ring 13 in this case
is rotated by a main shaft 14 as shown in FIG. In addition, the outer ring 1) is connected to the bearing box 12 in FIG.
It is fixed by fixing it to 4. Displacement sensor 23
is supported by a low-speed rotating turntable provided on the device main body 24 and coaxial with the main shaft 14.
また、他の例として第７図のように内輪１３を固定し、
外輪１）を高速回転し、変位センサー２３を低速回転さ
せる場合もある。この場合、外輪１）は第４図に示すご
とき主軸１４により回転される。また、第４図における
内輪回転軸３３を固定することにより内輪１３は固定さ
れる。変位センサー２３は前述のように低速回転のター
ンテーブルに支持される。In addition, as another example, the inner ring 13 is fixed as shown in FIG.
In some cases, the outer ring 1) is rotated at high speed and the displacement sensor 23 is rotated at low speed. In this case, the outer ring 1) is rotated by a main shaft 14 as shown in FIG. Further, the inner ring 13 is fixed by fixing the inner ring rotating shaft 33 in FIG. 4. As described above, the displacement sensor 23 is supported by a turntable that rotates at a low speed.
なお、内輪１３または外輪１）と変位センサー２３とは
、互いに逆方向に回転してもよい。Note that the inner ring 13 or outer ring 1) and the displacement sensor 23 may rotate in opposite directions.
上記のいずれの場合も、第３図のごとき記録図を得るこ
とができる。In any of the above cases, a recorded image as shown in FIG. 3 can be obtained.
以上のように、この発明の第一の手段及び第二の手段の
いずれにおいても、軸受の全周にわたり測定した非繰返
し精度を得ることができるものである。従って、当該軸
受のもつ非繰返し精度の最大値を基準値としてユーザー
に提供することにより、ユーザーは常に安全側で使用す
ることができる効果がある。As described above, in both the first means and the second means of the present invention, it is possible to obtain non-repeatable accuracy measured over the entire circumference of the bearing. Therefore, by providing the user with the maximum value of the non-repeatability of the bearing as a reference value, the user can always use the bearing on the safe side.
第１図はこの発明の第一の手段を実施する測定装置の断
面図とブロック図、第、′図は同上の一部拡大平面図、
第３図は非繰返し精度の記録図、第４図はこの発明の第
一の手段を実施する測定装置の断面図、第５図は同上の
ｖ−ｖｌにおける拡大断面図、第６図は第二の手段を実
施する測定装置の一部を示す拡大平面図、第７図は第二
の手段を実施する他の測定装置の一部を示す拡大平面図
、第８図は従来の測定装置の断面図、第９図は非繰返し
精度精度と変位センサーの位置との関係を示すグラフで
ある。
１０・・・・・・玉軸受、
１２・・・・・・軸受箱、
１４・・・・・・主軸、
２０・・・・・・従動プーリ、
３１・・・・・・弾性体、
１）・・・・・・外輪、
１３・・・・・・内輪、
１７・・・・・・従動プーリ、
２３・・・・・・変位センサー
３３・・・・・・内輪回転軸。
特許出願人 エヌ・チー・エヌ
東洋ベアリング株式会社
同 代理人
鎌
田
文
第７１
第８図
第９図
非繰返し精度
保持器成分1 is a sectional view and a block diagram of a measuring device implementing the first means of the present invention; FIGS. 1 and 2 are partially enlarged plan views of the same;
FIG. 3 is a recording diagram of non-repeatable accuracy, FIG. 4 is a cross-sectional view of a measuring device implementing the first means of the present invention, FIG. FIG. 7 is an enlarged plan view showing a part of a measuring device that implements the second means, FIG. 7 is an enlarged plan view showing a part of another measuring device that implements the second method, and FIG. The cross-sectional view, FIG. 9, is a graph showing the relationship between non-repeatability accuracy and the position of the displacement sensor. 10... Ball bearing, 12... Bearing box, 14... Main shaft, 20... Driven pulley, 31... Elastic body, 1 )... Outer ring, 13... Inner ring, 17... Driven pulley, 23... Displacement sensor 33... Inner ring rotating shaft. Patent Applicant: NCN Toyo Bearing Co., Ltd. Agent: Fumi Kamata 71 Figure 8 Figure 9 Non-repeatability cage components
Claims (2)
一体化するとともに、他方を低速回転軸と一体化し、上
記高速回転軸に接近して配置した変位計の変位センサー
を装置の固定部分に支持せしめ、両方の回転軸を回転さ
せながら変位計の出力信号を記録するようにした軸受の
非繰返し回転精度の測定方法。(1) One of the inner and outer rings of the bearing is integrated with the high-speed rotation shaft, and the other is integrated with the low-speed rotation shaft, and the displacement sensor of the displacement meter placed close to the high-speed rotation shaft is fixed to the device. A method for measuring the non-repetitive rotational accuracy of a bearing, in which the output signal from a displacement meter is recorded while both rotating shafts are rotated.
一体化するとともに、他方を装置の固定部分に支持せし
め、上記高速回転軸に接近して設置した変位計の変位セ
ンサーを高速回転軸と同軸で低速回転させながら変位計
の出力信号を記録するようにした軸受の非繰返し回転精
度の測定方法。(2) Either one of the inner ring or outer ring of the bearing is integrated with the high-speed rotation shaft, and the other is supported on a fixed part of the device, and the displacement sensor of the displacement meter installed close to the high-speed rotation shaft is rotated at high speed. A method for measuring the non-repetitive rotational accuracy of a bearing that records the output signal of a displacement meter while rotating at low speed coaxially with the shaft.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17592788A JP2820697B2 (en) | 1988-07-13 | 1988-07-13 | Non-repetitive rotation accuracy measurement method for bearings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17592788A JP2820697B2 (en) | 1988-07-13 | 1988-07-13 | Non-repetitive rotation accuracy measurement method for bearings |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0224529A true JPH0224529A (en) | 1990-01-26 |
| JP2820697B2 JP2820697B2 (en) | 1998-11-05 |
Family
ID=16004683
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17592788A Expired - Fee Related JP2820697B2 (en) | 1988-07-13 | 1988-07-13 | Non-repetitive rotation accuracy measurement method for bearings |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2820697B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003014537A (en) * | 2000-12-19 | 2003-01-15 | Nsk Ltd | Vibration diagnosis apparatus for rotary apparatus |
| CN105547669A (en) * | 2015-12-12 | 2016-05-04 | 哈尔滨东安汽车动力股份有限公司 | Synchronization device rotary inertia simulation test device |
| CN106032973A (en) * | 2015-03-12 | 2016-10-19 | 成都豪能科技股份有限公司 | Integrated gauge for straight-oil-groove synchronous loop forge piece |
-
1988
- 1988-07-13 JP JP17592788A patent/JP2820697B2/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003014537A (en) * | 2000-12-19 | 2003-01-15 | Nsk Ltd | Vibration diagnosis apparatus for rotary apparatus |
| CN106032973A (en) * | 2015-03-12 | 2016-10-19 | 成都豪能科技股份有限公司 | Integrated gauge for straight-oil-groove synchronous loop forge piece |
| CN106032973B (en) * | 2015-03-12 | 2018-08-14 | 成都豪能科技股份有限公司 | Straight oil groove synchronizes ring forging comprehensive check tool |
| CN105547669A (en) * | 2015-12-12 | 2016-05-04 | 哈尔滨东安汽车动力股份有限公司 | Synchronization device rotary inertia simulation test device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2820697B2 (en) | 1998-11-05 |
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