JPH028673Y2 - - Google Patents
Info
- Publication number
- JPH028673Y2 JPH028673Y2 JP6246485U JP6246485U JPH028673Y2 JP H028673 Y2 JPH028673 Y2 JP H028673Y2 JP 6246485 U JP6246485 U JP 6246485U JP 6246485 U JP6246485 U JP 6246485U JP H028673 Y2 JPH028673 Y2 JP H028673Y2
- Authority
- JP
- Japan
- Prior art keywords
- spindle
- bearing
- bearing metal
- static pressure
- metal
- 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.)
- Expired
Links
- 229910000897 Babbitt (metal) Inorganic materials 0.000 claims description 28
- 230000003068 static effect Effects 0.000 claims description 17
- 239000000463 material Substances 0.000 claims description 8
- 230000002093 peripheral effect Effects 0.000 claims description 5
- 230000002706 hydrostatic effect Effects 0.000 description 11
- 239000003921 oil Substances 0.000 description 7
- 239000010687 lubricating oil Substances 0.000 description 6
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
Landscapes
- Turning (AREA)
- Machine Tool Units (AREA)
- Sliding-Contact Bearings (AREA)
- Magnetic Bearings And Hydrostatic Bearings (AREA)
Description
【考案の詳細な説明】
〔産業上の利用分野〕
本考案は超精密平面研削盤の回転テーブル等を
軸支するのに適した工作機械の軸受装置に関す
る。[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a bearing device for a machine tool suitable for supporting a rotating table of an ultra-precision surface grinder.
この種の精度を要する工作機械の軸受装置に
は、ベツドに支持される軸受メタルとこれに軸支
されるスピンドルよりなり、この軸受メタルの内
周面は前記スピンドルの中間部の外周面と嵌合
し、同軸受メタルの両端面は前記スピンドルの中
間部の両端に形成されたフランジの互に対向する
摺動面の間に挟持されて摺動可能に係合し、軸受
メタルの前記内周面にはラジアル静圧軸受を、前
記両端面にはスラスト静圧軸受を設けてなるもの
があり、これによれば比較的小さな軸受長さで静
圧軸受の支持剛性を高めることができ、しかもそ
の構造は極めて簡単である。しかして、従来はス
ピンドルには鋼を、軸受メタルには砲金を使用す
るのが普通であつた。
A bearing device for a machine tool that requires this kind of precision consists of a bearing metal supported by a bed and a spindle supported by this. and both end surfaces of the bearing metal are sandwiched and slidably engaged between opposing sliding surfaces of flanges formed at both ends of the intermediate portion of the spindle, and the inner periphery of the bearing metal There is a type in which a radial hydrostatic pressure bearing is provided on the surface and a thrust hydrostatic pressure bearing is provided on both end surfaces, and with this, the support rigidity of the hydrostatic pressure bearing can be increased with a relatively small bearing length, and also. Its structure is extremely simple. Conventionally, it was common to use steel for the spindle and gunmetal for the bearing metal.
しかしながら、かゝる従来技術においてはスラ
スト静圧軸受間の距離が長くなり、しかもその長
さの軸受メタルとスピンドルの線膨張係数が異な
るので（鋼：約12×10-6／℃、砲金：約18.3×
10-6／℃）、スピンドルの回転等により温度が上
昇すればスラスト静圧軸受とスピンドルの摺動面
との〓間が減少し、これによる焼付を考慮しなけ
ればならないので、前記〓間を小としてスラスト
静圧軸受の支持剛性を高めるというこの種の軸受
装置の利点を充分活用することができなかつた。
本考案はこのような問題を解決しようとするもの
である。
However, in such conventional technology, the distance between the thrust hydrostatic bearings is long, and the linear expansion coefficients of the bearing metal and spindle over that length are different (steel: approximately 12×10 -6 /℃, gun metal: Approximately 18.3×
10 -6 /℃), as the temperature rises due to spindle rotation, etc., the distance between the thrust static pressure bearing and the sliding surface of the spindle decreases, and seizure due to this must be taken into consideration. Due to its small size, it has not been possible to fully utilize the advantage of this type of bearing device, which is to increase the supporting rigidity of the thrust hydrostatic bearing.
The present invention attempts to solve such problems.
このために、本考案による工作機械の軸受装置
は、第１図及び第２図に示す如く、ベツド１０に
支持される軸受メタル３０とこれに軸支されるス
ピンドル４０よりなり、この軸受メタル３０の内
周面３１は前記スピンドル４０の中間部４２の外
周面４５と嵌合し、両軸受メタル３０の両端面３
２，３３はスピンドル４０の中間部４２の両端に
形成されたフランジ４３，４４の互に対向する摺
動面４６，４７の間に挟持され、軸受メタル３０
の前記内周面３１にはラジアル静圧軸受３１ａ
を、前記両端面３２，３３にはスラスト静圧軸受
３２ａ，３３ａを設けてなる工作機械の軸受装置
において、軸受メタル３０の材質をスピンドル４
０の材質と同一としたことを特徴とするものであ
る。
For this reason, the bearing device for a machine tool according to the present invention, as shown in FIGS. 1 and 2, consists of a bearing metal 30 supported by a bed 10 and a spindle 40 supported by the bearing metal 30. The inner circumferential surface 31 of the spindle 40 is fitted with the outer circumferential surface 45 of the intermediate portion 42 of the spindle 40, and both end surfaces 3 of the both bearing metals 30 are fitted.
2 and 33 are sandwiched between mutually opposing sliding surfaces 46 and 47 of flanges 43 and 44 formed at both ends of the intermediate portion 42 of the spindle 40, and the bearing metal 30
A radial static pressure bearing 31a is provided on the inner peripheral surface 31 of
In a machine tool bearing device in which thrust static pressure bearings 32a and 33a are provided on both end surfaces 32 and 33, the material of the bearing metal 30 is different from that of the spindle 4.
This material is characterized by being made of the same material as No. 0.
周囲の温度の変化や、スピンドル４０の回転に
ともなう静圧軸受３１ａ，３２ａ，３３ａの潤滑
油の流体摩擦による発熱などにより軸受メタル３
０及びスピンドル４０の温度は変化する。この温
度変化により軸受メタル３０およびスピンドル４
０は膨張収縮するが、この両部材３０，４０の材
質は同一であるのでこの膨張収縮量は互に同一で
あり、従つてスラスト静圧軸受３２ａ，３３ａと
スピンドル４０のフランジ４３，４４の摺動面４
６，４７との間の〓間は変化しない。
The bearing metal 3 may be damaged due to changes in ambient temperature or heat generation due to fluid friction of the lubricating oil of the hydrostatic bearings 31a, 32a, 33a as the spindle 40 rotates.
0 and the temperature of the spindle 40 change. Due to this temperature change, the bearing metal 30 and spindle 4
0 expands and contracts, but since both members 30 and 40 are made of the same material, the amounts of expansion and contraction are the same. Moving surface 4
The interval between 6 and 47 remains unchanged.
上述の如く、本考案によれば、温度が変化して
もスラスト静圧軸受とスピンドルの摺動面との間
の〓間は変化しないので、この〓間が常にスピン
ドルを静圧支持するのに必要な最小限の値となる
ようにすることができ、従つてスピンドルの支持
剛性を高めることができる。
As mentioned above, according to the present invention, the distance between the thrust hydrostatic pressure bearing and the sliding surface of the spindle does not change even if the temperature changes, so this distance always supports the spindle under static pressure. It is possible to achieve the required minimum value, and therefore the support rigidity of the spindle can be increased.
以下に、添付図面により、超精密平面研削盤に
おける実施例を説明する。
An embodiment of an ultra-precision surface grinder will be described below with reference to the accompanying drawings.
第２図に示す如く、ベツド１０上にはコラム１
１が立設され、同コラム１１には主軸頭１２が鉛
直方向に摺動可能に案内支持され、送りモータ１
４により送り移動が与えられている。主軸頭１２
に鉛直方向軸線回りに軸支された主軸１３は主軸
駆動モータ１５により回転駆動され、主軸１３の
下端には平面研削用の砥石Ｇが装着されている。
主軸頭１２の下方のベツド１０上には、真空チヤ
ツク５５を介して工作物Ｗを支持する回転テーブ
ル４０が、本考案による軸受装置を介して、鉛直
方向軸線回りに回転自在に軸支されている。 As shown in Figure 2, column 1 is placed on bed 10.
A spindle head 12 is vertically slidably guided and supported on the column 11, and a feed motor 1 is installed vertically.
The feed movement is given by 4. Spindle head 12
A main shaft 13 supported around a vertical axis is rotationally driven by a main shaft drive motor 15, and a grindstone G for surface grinding is attached to the lower end of the main shaft 13.
On the bed 10 below the spindle head 12, a rotary table 40 that supports a workpiece W via a vacuum chuck 55 is rotatably supported around a vertical axis via a bearing device according to the present invention. There is.
第１図に示す如く、上部が回転テーブル４１を
形成するスピンドル４０は、ベツド１０上に固定
された軸受メタル３０により軸支されている。軸
受メタル３０は鉛直な円筒状の内周面３１と水平
な上下端面３２，３３を有し、上部外周のフラン
ジにより支持台２０を介してベツド１０上に固定
されている。軸受メタル３０の内周面３１にはポ
ケツトを設けてラジアル静圧軸受３１ａが形成さ
れ、また上下端面３２，３３にもそれぞれポケツ
トを設けてスラスト静圧軸受３２ａ，３３ａが形
成されている。軸受メタル３０の材質はスピンド
ル４０と同じく鋼等の鉄系の金属とする。 As shown in FIG. 1, a spindle 40 whose upper portion forms a rotary table 41 is supported by a bearing metal 30 fixed on the bed 10. As shown in FIG. The bearing metal 30 has a vertical cylindrical inner circumferential surface 31 and horizontal upper and lower end surfaces 32 and 33, and is fixed on the bed 10 via a support base 20 by a flange on the upper outer circumference. The inner peripheral surface 31 of the bearing metal 30 is provided with a pocket to form a radial static pressure bearing 31a, and the upper and lower end surfaces 32 and 33 are also provided with pockets, respectively, to form thrust static pressure bearings 32a and 33a. The material of the bearing metal 30 is, like the spindle 40, an iron-based metal such as steel.
軸受メタル３０には外周に環状溝３４を形成す
ると共に同環状溝３４から各静圧軸受３１ａ，３
２ａ，３３ａに連通する油路３５を設け、各油路
３５にはそれぞれ絞り３６を設ける。また支持台
２０とその下側に固定した下部ハウジング２１に
は、環状溝３４に連通する油路２３を設け、その
下端の潤滑油入口２３ａに供給される潤滑油ポン
プ（図示せず）からの加圧潤滑油が油路２３、環
状溝３４、油路３５及び絞り３６を経て各静圧軸
受３１ａ，３２ａ，３３ａに供給されるようにす
る。支持台２０及び軸受メタル３０には使用済の
潤滑油を下部ハウジング２１内に戻す戻し油路２
４が設けられ、下部ハウジング２１の下部には集
つた潤滑油をリザーバ（図示せず）に戻す排出管
２５が接続されている。 An annular groove 34 is formed on the outer periphery of the bearing metal 30, and each hydrostatic bearing 31a, 3 is connected to the annular groove 34 from the annular groove 34.
Oil passages 35 communicating with 2a and 33a are provided, and each oil passage 35 is provided with a throttle 36, respectively. Further, the support base 20 and the lower housing 21 fixed to the lower side thereof are provided with an oil passage 23 communicating with the annular groove 34, and a lubricating oil pump (not shown) is supplied to the lubricating oil inlet 23a at the lower end of the oil passage 23. Pressurized lubricating oil is supplied to each hydrostatic bearing 31a, 32a, 33a through the oil passage 23, annular groove 34, oil passage 35, and throttle 36. The support base 20 and the bearing metal 30 are provided with return oil passages 2 for returning used lubricating oil into the lower housing 21.
4 is provided, and a discharge pipe 25 is connected to the lower part of the lower housing 21 for returning the collected lubricating oil to a reservoir (not shown).
スピンドル４０は上部の回転テーブル４１と下
部の回転軸４１ａを同軸に一体結合してなり、回
転テーブル４１の下半部には円柱状の中間部４２
が形成され、この中間部４２の上下端にはそれぞ
れ上フランジ４３及び下フランジ４４が形成され
ている。下フランジ４４は中間部４２の下側に係
合された回転軸４１ａの上半分をなしている。ス
ピンドル４０の中間部４２の外周面４５は必要な
最小隙間をおいて軸受メタル３０の内周面３１と
嵌合し、また上フランジ４３下面の摺動面４６と
下フランジ４４上面の摺動面４７は互に対向し、
この両摺動面４６，４７はそれぞれ必要な最小隙
間を隔てゝ軸受メタル３０の上下端面３２，３３
を挟持し、これと摺動可能に対面している。かく
してスピンドル４０は軸受メタル３０に形成され
たラジアル静圧軸受３１ａ及びスラスト静圧軸受
３２ａ，３３ａにより軸方向移動不能に軸支され
るものである。回転軸４１ａの下半部は細径とな
つて下部ハウジング２１中央のボス部２１ａを貫
通して下方に突出し、ボス部２１ａの外周に軸支
されたプーリ５０の外周に設けられた複数の切欠
部５０ａには回転軸４１ａの下端に固定された円
板５１に設けられた突起５１ａが係合し、このプ
ーリ５０、切欠部５０ａ、突起５１ａ及び円板５
１を介してスピンドル４０はスピンドル駆動モー
タ（図示せず）により回転駆動される。回転テー
ブル４１の上面には工作物Ｗを保持する真空チヤ
ツク５５が固定され、この真空チヤツク５５は回
転テーブル４１及び回転軸４１ａに形成された通
路４８，４８ａ、延長部材２２を介して下部ハウ
ジング２１に支持された継手２７およびホース２
６を介して真空ポンプ（図示せず）に接続されて
いる。 The spindle 40 is formed by integrally coaxially coupling an upper rotary table 41 and a lower rotary shaft 41a, and a cylindrical intermediate portion 42 is provided in the lower half of the rotary table 41.
An upper flange 43 and a lower flange 44 are formed at the upper and lower ends of the intermediate portion 42, respectively. The lower flange 44 forms the upper half of the rotating shaft 41a that is engaged with the lower side of the intermediate portion 42. The outer circumferential surface 45 of the intermediate portion 42 of the spindle 40 is fitted with the inner circumferential surface 31 of the bearing metal 30 with a necessary minimum clearance, and the sliding surface 46 on the lower surface of the upper flange 43 and the sliding surface on the upper surface of the lower flange 44 47 are facing each other,
These sliding surfaces 46 and 47 are spaced apart from each other by a necessary minimum clearance.The upper and lower end surfaces 32 and 33 of the bearing metal 30
is sandwiched and slidably faces this. Thus, the spindle 40 is supported by the radial static pressure bearing 31a and the thrust static pressure bearings 32a, 33a formed in the bearing metal 30 so as not to be able to move in the axial direction. The lower half of the rotating shaft 41a has a small diameter and protrudes downward through the boss portion 21a at the center of the lower housing 21, and has a plurality of notches provided on the outer periphery of a pulley 50 that is pivotally supported on the outer periphery of the boss portion 21a. A protrusion 51a provided on a disc 51 fixed to the lower end of the rotating shaft 41a engages with the part 50a, and the pulley 50, the notch 50a, the protrusion 51a and the disc 5
1, the spindle 40 is rotationally driven by a spindle drive motor (not shown). A vacuum chuck 55 that holds the workpiece W is fixed to the upper surface of the rotary table 41, and the vacuum chuck 55 is connected to the lower housing 21 through the passages 48, 48a formed in the rotary table 41 and the rotary shaft 41a, and the extension member 22. Joint 27 and hose 2 supported by
6 to a vacuum pump (not shown).
次に本実施例の作動につき説明すれば、先ず潤
滑油入口２３ａからの加圧潤滑油は軸受メタル３
０に設けられたラジアル静圧軸受３１ａ及びスラ
スト静圧軸受３２ａ，３３ａに供給されてスピン
ドル４０を静圧支持する。静圧支持されたスピン
ドル４０はプーリ５０等を介してスピンドル駆動
モータにより回転駆動され、一方主軸頭１２に軸
支されて回転駆動される主軸１３の下端に装着さ
れた砥石Ｇは主軸頭１２と共に送りモータ１４に
より下降し、回転テーブル１４上の真空チヤツク
５５に保持された工作物Ｗを平面研削加工する。
周囲の温度変化や静圧軸受３１ａ，３２ａ，３３
ａの発熱などにより軸受メタル３０及びスピンド
ル４０の温度が変化しても、両部材３０，４０は
同一材質であり熱膨張係数はほゞ等しいのでスラ
スト静圧軸受３２ａ，３３ａとスピンドル４０の
摺動面４６，４７との隙間は殆ど変化することな
く必要な最小隙間に保たれ、従つて加工反力を主
として支持するスラスト静圧軸受３２ａの支持剛
性は最大に保たれるので温度変化により加工精度
が低下することはない。 Next, to explain the operation of this embodiment, first, the pressurized lubricant from the lubricant inlet 23a is supplied to the bearing metal 3.
It is supplied to a radial static pressure bearing 31a and thrust static pressure bearings 32a and 33a provided at 0, and supports the spindle 40 under static pressure. The spindle 40 supported by static pressure is rotationally driven by a spindle drive motor via a pulley 50 etc., while the grinding wheel G attached to the lower end of the main shaft 13 which is rotatably supported by the main spindle head 12 is rotated together with the main spindle head 12. The workpiece W, which is lowered by the feed motor 14 and held by the vacuum chuck 55 on the rotary table 14, is subjected to surface grinding.
Ambient temperature changes and static pressure bearings 31a, 32a, 33
Even if the temperatures of the bearing metal 30 and the spindle 40 change due to heat generated by the thrust bearings 32a, 33a and the spindle 40, the thrust static pressure bearings 32a, 33a and the spindle 40 will not slide because both members 30, 40 are made of the same material and have approximately the same coefficient of thermal expansion. The gap between the surfaces 46 and 47 hardly changes and is maintained at the required minimum gap. Therefore, the support rigidity of the thrust hydrostatic bearing 32a, which mainly supports the processing reaction force, is maintained at the maximum, so the processing accuracy is improved by temperature changes. will not decrease.
本考案は、本実施例の回転テーブルの如く、比
較的低速で回転するスピンドルを軸支する場合に
特に適している。 The present invention is particularly suitable for supporting a spindle that rotates at a relatively low speed, such as the rotary table of this embodiment.
図面は本考案による工作機械の軸受装置の超静
密平面研削盤における一実施例を示し、第１図は
主要部の縦断面図、第２図は全体側面図である。
符号の説明、１０……ベツド、３０……軸受メ
タル、３１……内周面、３１ａ……ラジアル静圧
軸受、３２，３３……両端面、３２ａ，３３ａ…
…スラスト静圧軸受、４０……スピンドル、４２
……中間部、４３，４４……フランジ、４５……
外周面、４６，４７……摺動面。
The drawings show an embodiment of a bearing device for a machine tool according to the present invention in an ultra-static surface grinder, in which FIG. 1 is a longitudinal cross-sectional view of the main part, and FIG. 2 is a side view of the whole. Explanation of symbols, 10...Bed, 30...Bearing metal, 31...Inner peripheral surface, 31a...Radial static pressure bearing, 32, 33...Both end surfaces, 32a, 33a...
...Thrust hydrostatic bearing, 40...Spindle, 42
... Middle part, 43, 44 ... Flange, 45 ...
Outer peripheral surface, 46, 47...sliding surface.
Claims (1)
れるスピンドルよりなり、この軸受メタルの内周
面は前記スピンドルの中間部の外周面と嵌合し、
同軸受メタルの両端面は前記スピンドルの中間部
の両端に形成されたフランジの互に対向する摺動
面の間に挟持され、軸受メタルの前記内周面には
ラジアル静圧軸受を、前記両端面にはスラスト静
圧軸受を設けてなる工作機械の軸受装置におい
て、前記軸受メタルの材質を前記スピンドルの材
質と同一としたことを特徴とする工作機械の軸受
装置。 Consisting of a bearing metal supported by the bed and a spindle pivotally supported by this, the inner circumferential surface of the bearing metal fits with the outer circumferential surface of the intermediate portion of the spindle,
Both end surfaces of the same bearing metal are sandwiched between mutually opposing sliding surfaces of flanges formed at both ends of the intermediate portion of the spindle, and a radial static pressure bearing is mounted on the inner peripheral surface of the bearing metal, and 1. A bearing device for a machine tool comprising a thrust static pressure bearing on a surface thereof, wherein the material of the bearing metal is the same as the material of the spindle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6246485U JPH028673Y2 (en) | 1985-04-25 | 1985-04-25 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6246485U JPH028673Y2 (en) | 1985-04-25 | 1985-04-25 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61178642U JPS61178642U (en) | 1986-11-07 |
| JPH028673Y2 true JPH028673Y2 (en) | 1990-03-01 |
Family
ID=30591701
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6246485U Expired JPH028673Y2 (en) | 1985-04-25 | 1985-04-25 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH028673Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6015357B2 (en) * | 2012-11-01 | 2016-10-26 | 株式会社ジェイテクト | Machine Tools |
-
1985
- 1985-04-25 JP JP6246485U patent/JPH028673Y2/ja not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61178642U (en) | 1986-11-07 |
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