KR20170019690A - Hydrostatic bearing and machine tool having the same - Google Patents

Hydrostatic bearing and machine tool having the same Download PDF

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Publication number
KR20170019690A
KR20170019690A KR1020150113819A KR20150113819A KR20170019690A KR 20170019690 A KR20170019690 A KR 20170019690A KR 1020150113819 A KR1020150113819 A KR 1020150113819A KR 20150113819 A KR20150113819 A KR 20150113819A KR 20170019690 A KR20170019690 A KR 20170019690A
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South Korea
Prior art keywords
pocket portion
journal
thrust
rotating body
fluid
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KR1020150113819A
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Korean (ko)
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KR101727813B1 (en
Inventor
박성욱
Original Assignee
현대위아 주식회사
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Priority to KR1020150113819A priority Critical patent/KR101727813B1/en
Publication of KR20170019690A publication Critical patent/KR20170019690A/en
Application granted granted Critical
Publication of KR101727813B1 publication Critical patent/KR101727813B1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C32/00—Bearings not otherwise provided for
    • F16C32/06—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings
    • F16C32/0629—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings supported by a liquid cushion, e.g. oil cushion
    • F16C32/064—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings supported by a liquid cushion, e.g. oil cushion the liquid being supplied under pressure
    • F16C32/0651—Details of the bearing area per se
    • F16C32/0659—Details of the bearing area per se of pockets or grooves
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
    • B23Q1/25—Movable or adjustable work or tool supports
    • B23Q1/26—Movable or adjustable work or tool supports characterised by constructional features relating to the co-operation of relatively movable members; Means for preventing relative movement of such members
    • B23Q1/38—Movable or adjustable work or tool supports characterised by constructional features relating to the co-operation of relatively movable members; Means for preventing relative movement of such members using fluid bearings or fluid cushion supports
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q5/00—Driving or feeding mechanisms; Control arrangements therefor
    • B23Q5/02—Driving main working members
    • B23Q5/04—Driving main working members rotary shafts, e.g. working-spindles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C32/00—Bearings not otherwise provided for
    • F16C32/06—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings
    • F16C32/0629—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings supported by a liquid cushion, e.g. oil cushion
    • F16C32/0633—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings supported by a liquid cushion, e.g. oil cushion the liquid being retained in a gap
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C32/00—Bearings not otherwise provided for
    • F16C32/06—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings
    • F16C32/0681—Construction or mounting aspects of hydrostatic bearings, for exclusively rotary movement, related to the direction of load
    • F16C32/0696—Construction or mounting aspects of hydrostatic bearings, for exclusively rotary movement, related to the direction of load for both radial and axial load
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2322/00—Apparatus used in shaping articles

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Magnetic Bearings And Hydrostatic Bearings (AREA)
  • Turning (AREA)

Abstract

The present invention includes a hydrostatic pressure bearing disposed between a rotating body and a holding body holding the rotating body and having at least two annular pockets formed on a contact surface of the rotating body or the holding body to thereby provide a fluid to be supplied only to one of pocket portions when rotating in a high speed or a low speed to provide an effective bearing according to a rotation speed of a rotating body and a machine tool including the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hydrostatic bearing and a machine tool including the hydrostatic bearing,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrostatic pressure bearing and a machine tool having improved structures, and more particularly, to a hydrostatic pressure bearing which can be used in a machine tool and a machine tool including the same.

In general, a high-speed spindle constituting a machine tool is equipped with a spindle bearing. As the spindle bearing, an angular contact ball bearing mainly resistant to a stress load, a rolling bearing such as a roller bearing or an oil bearing is used have.

Rolling bearings have the advantages of both high stiffness and dynamic rigidity, and a simple structure. However, they have a disadvantage in that the precision of the workpiece is deteriorated due to frictional loss during high-speed rotation and the resulting heat.

In addition, friction, vibration, heat, and noise are generated by the rolling motion of the bearing when the main shaft rotates, thereby deteriorating the surface quality of the machined surface and shortening the life of the bearing.

In addition, rolling bearings require a preload for smooth operation and require the use of additional elements such as springs.

On the other hand, hydrostatic bearings (oil bearings) support the radial and axial movements of the main shaft in a noncontact manner using a medium such as oil. Therefore, their life span is semi-permanent and has advantages of stiffness and damping.

However, these hydrostatic bearings have structural defects that lubricant can leak out, resulting in contamination problems.

In addition, when the pocket in which the oil is received is divided into small portions, it is intended for high-speed rotation. However, such a small pocket type hydrostatic pressure bearing has a small load capacity and low rigidity while the temperature rise amount and flow rate are small.

On the contrary, when the pockets of the hydrostatic bearings are large, they are for low-speed rotation. However, these large pocket hydrostatic bearings have a large load capacity and rigidity, and a large amount of temperature rise and flow.

Korean Patent Publication No. 10-0359185

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hydrostatic pressure bearing having excellent effects without regard to high speed rotation and low speed rotation of a rotating body and a machine tool including the hydrostatic bearing.

The present invention also provides a hydraulic pressure bearing having high durability and little oil leakage, and a machine tool including the same.

In order to achieve the above-mentioned object, the present invention is characterized in that, in order to achieve the above object, at least two annular pockets formed on a contact surface of the rotating body or the fixing body, Thereby providing a hydrostatic bearing.

The hydrostatic bearing includes a first thrust pocket portion formed on a contact surface of the fixture and spaced apart from the rotating body and a second thrust pocket portion formed between the rotating body and the first thrust pocket portion .

The first thrust pocket portion and the second thrust pocket portion may include four pockets formed at regular intervals.

The first thrust pocket portion may have a longer radial length than the second thrust pocket portion.

Wherein the first thrust pocket portion and the second thrust pocket portion are supplied with fluid only in one of the first thrust pocket portion and the second thrust pocket portion when the rotating body rotates at a speed higher than a predetermined speed, The fluid can be supplied to the first thrust pocket portion and the second thrust pocket portion when the rotating body rotates at a predetermined speed or lower.

The fluid can be supplied to the second thrust pocket portion when the rotating body rotates at a speed higher than a predetermined speed.

A first journal pocket portion formed on a contact surface of the rotating body and spaced apart from an end of the rotating body, a second journal pocket portion formed between the end of the rotating body and the first journal pocket portion, And may include pocket portions.

The first journal pocket portion and the second journal pocket portion may include four pockets formed at regular intervals.

The first journal pocket portion may have a longer axial length than the second journal pocket portion.

Wherein the first journal pocket portion and the second journal pocket portion are supplied with fluid only in one of the first journal pocket portion and the second journal pocket portion when the rotating body rotates at a speed higher than a predetermined speed, The fluid may be supplied to the first journal pocket portion and the second journal pocket portion when the rotating body rotates at a predetermined speed or less.

The fluid can be supplied to the second journal pocket portion when the rotating body rotates at a speed higher than a predetermined speed.

According to another aspect of the present invention, there is provided a stator for a stator, comprising: a first thrust pocket portion disposed between a rotating body and a holding body for holding the rotating body, the first thrust pocket portion being formed on a contact surface of the holding body, A second thrust pocket portion formed on a contact surface of the fixture body and formed between the rotator and the first thrust pocket portion; A first journal pocket formed on a contact surface of the rotating body and spaced apart from a distal end of the rotating body; And a second journal pocket formed on a contact surface of the rotating body and formed between the end of the rotator and the first journal pocket.

The first thrust pocket portion may have a longer radial length than the second thrust pocket portion, and the first journal pocket portion may have a longer axial length than the second journal pocket portion.

Wherein the first thrust pocket portion, the second thrust pocket portion, the first journal pocket portion, and the second journal pocket portion are configured such that when the rotating body rotates at a speed higher than a predetermined speed, Wherein fluid is supplied to one of the second thrust pocket portions and fluid is supplied to one of the first journal pocket portion and the second journal pocket portion, and when the rotating body rotates below a predetermined speed, Fluid may be supplied to the thrust pocket portion, the second thrust pocket portion, the first journal pocket portion, and the second journal pocket portion.

The fluid may be supplied to the second thrust pocket portion and the second journal pocket portion when the rotating body rotates at a speed higher than a predetermined speed.

The present invention also relates to a spindle as a rotating body; A housing for holding the spindle; And a hydrostatic pressure bearing.

The present invention is characterized in that it includes a hydrostatic bearing formed so as to have at least two pockets formed in a portion in contact with a housing or a rotating body so that the fluid can be effectively circulated by varying the fluid supply according to the high- The friction can be reduced.

In addition, the present invention can improve the prevention of leakage of fluid, decrease in temperature rise, decrease in fluid supply amount, and durability.

1 is a sectional view showing a rotating body, a fixed body, and a hydrostatic pressure bearing according to an embodiment of the present invention,
FIG. 2 is an enlarged cross-sectional view of the front bearing portion in FIG. 1,
3 is a perspective view showing the hydrostatic bearing of FIG. 1,
Fig. 4 is a front view of Fig. 3,
Fig. 5 is a rear view of Fig. 3,
Fig. 6 is a sectional view of Fig. 3. Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Unless defined otherwise, all terms used herein are the same as the generic meanings of the terms understood by those of ordinary skill in the art, and where the terms used herein contradict the general meaning of the term, they shall be as defined herein.

It is to be understood, however, that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

FIG. 1 is a sectional view showing a rotating body, a stationary body, and a hydrostatic pressure bearing according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of the front bearing part in FIG.

1 and 2, a hydrostatic pressure bearing 100 according to an embodiment of the present invention may be included in the machine tool 10.

Specifically, the hydrostatic pressure bearing 100 according to the embodiment includes a spindle as a rotating body 11 and a fixed body 12 that receives the spindle as the rotating body 11, The rotation of the spindle can be smoothly achieved in the housing, which is the fixing member 12.

The hydrostatic pressure bearing 100 according to this embodiment will be described in more detail as follows.

Fig. 3 is a perspective view showing the hydrostatic bearing of Fig. 1, Fig. 4 is a front view of Fig. 3, Fig. 5 is a rear view of Fig. 3, and Fig. 6 is a sectional view of Fig.

1 to 6, a hydrostatic pressure bearing 100 according to an embodiment is disposed between a rotating body 11 and a fixed body 12 that receives the rotating body 11, At least two annular first pocket portions 110 formed on the contact surfaces of the first and second pocket portions 12 may be disposed.

Although the rotary body 11 is described as a spindle in the machine tool 10, it may suffice if it is rotatable within the fixture 12 such as the fixture 12. [

Specifically, the hydrostatic bearing 100 includes a first thrust pocket portion 110a formed on the contact surface of the fixing body 12 and spaced apart from the rotating body 11, And a second thrust pocket portion 110b formed between the first thrust pocket portion 110a and the first thrust pocket portion 110a.

The first thrust pocket portion 110a and the second thrust pocket portion 110b are formed by connecting a fluid supplied from the outside by an oil pump or the like to the first thrust pocket portion 110a and the second thrust pocket portion 110b Through the flow path 130 communicated with each other.

The flow of this fluid is transmitted to the first thrust pocket portion 110a only, to the second thrust pocket portion 110b only, or to the first thrust pocket portion 110a and the second thrust pocket portion 110b, May be supplied at the same time.

Also, as shown in FIG. 3, the first thrust pocket portion 110a or the second thrust pocket portion 110b may include four pockets formed at regular intervals.

That is, as shown in FIG. 3, the first thrust pocket portion 110a may include four pockets formed at an equal interval in the circumferential direction from the radially outer side with respect to the rotation axis, The portion 110b may include four pockets formed at equal intervals in the circumferential direction from the radially inner side with respect to the rotation axis.

The first thrust pocket portion 110a may be formed to have a length greater than that of the second thrust pocket portion 110b with respect to a direction from the rotation shaft toward the outer circumferential surface. That is, the first thrust pocket portion 110a may be longer than the second thrust pocket portion 110b in the radial direction.

The hydrostatic bearing 100 according to the embodiment can be controlled so that fluid is supplied only to the second thrust pocket portion 110b when the rotating body 11 rotates at a high speed.

This is because when the hydrostatic bearing 100 rotates at a high speed, frictional heat of the pocket and the oil and a large flow rate may cause problems in design implementation. That is, since the radius (or volume) of the second thrust pocket portion 110b is smaller than that of the first thrust pocket portion 110a during high-speed rotation of the rotating body 11, the amount of increase in temperature due to the flow rate and / This is because it is advantageous.

Here, the high speed rotation may vary depending on the type of the rotating body 11 and / or the volume of the hydrostatic bearing 100 according to the embodiment, but in the case of the machine tool 10, for example, about 5,000 rpm Can be exceeded.

On the other hand, in the case of low-speed rotation requiring a high cutting load and high rigidity, the first thrust pocket portion 110a and the second thrust pocket portion 110b are preferably simultaneously driven.

1 to 6, the hydrostatic pressure bearing 100 according to the embodiment is disposed between a rotating body 11 and a fixed body 12 that receives the rotating body 11, At least two annular second pocket portions 120 formed on the contact surfaces of the first and second pocket portions 11 may be disposed.

Although the rotating body 11 is described as a spindle in the machine tool 10, it is sufficient if it is rotatable in a housing such as the fixing body 12. [

Specifically, the hydrostatic pressure bearing 100 includes a first journal pocket portion 120a formed on a contact surface of the rotating body 11 and spaced apart from a distal end of the rotating body 11, And a second journal pocket portion 120b formed between the end of the first journal pocket portion 11a and the first journal pocket portion 120a.

The first journal pocket portion 120a and the second journal pocket portion 120b are formed by connecting a fluid supplied from the outside by an oil pump (not shown) or the like to the first journal pocket portion 120a and the second journal pocket portion 120b Through the flow path 130 communicated with each other.

This flow of fluid is controlled by the unshown control portion only in the first journal pocket portion 120a, in the second journal pocket portion 120b, or in the first journal pocket portion 120a and the second journal pocket portion 120b May be supplied at the same time.

Also, as shown in FIGS. 1 and 6, the first journal pocket portion 120a or the second journal pocket portion 120b may include four pockets formed at regular intervals.

That is, as shown in FIGS. 1 and 6, the first journal pocket portion 120a includes four pockets formed at regular intervals in the circumferential direction at a portion spaced from the end of the rotating body 11 with respect to the rotation axis can do.

In addition, the second journal pocket portion 120b may include four pockets formed at equal intervals in the circumferential direction between the end of the rotation shaft and the first journal pocket portion 120a.

In addition, the first journal pocket portion 120a may be formed to have a length greater than the length of the second journal pocket portion 120b with respect to the longitudinal direction of the rotation shaft. That is, the first journal pocket portion 120a may have a longer axial length than the second journal pocket portion 120b.

The hydrostatic bearing 100 according to the embodiment can be controlled so that fluid is supplied only to the second journal pocket portion 120b when the rotating body 11 rotates at a high speed. This is because when the hydrostatic bearing 100 rotates at a high speed, frictional heat of the pocket and the oil and a large flow rate may cause problems in design implementation.

That is, since the radius (or volume) of the second journal pocket portion 120b is smaller than that of the first journal pocket portion 120a during high-speed rotation of the rotating body 11, the amount of temperature rise due to the flow rate and / This is because it is advantageous.

Further, since the tool is clamped to the distal end of the rotating body 11 to be heavy, the rotating shaft can be stably supported.

Here, the high speed rotation may vary depending on the type of the rotating body 11 and / or the volume of the hydrostatic bearing 100 according to the embodiment, but in the case of the machine tool 10, for example, about 5,000 rpm Can be exceeded.

Meanwhile, in the case of a low-speed rotation requiring a high cutting load and a high rigidity, the first journal pocket portion 120a or the second journal pocket portion 120b may be simultaneously driven.

As shown in the figure, the first thrust pocket portion 110a, the second thrust pocket portion 110b, the first journal pocket portion 120a, And the second journal pocket portion 120b.

In this case, the fluid flowing through the passage 130 may include only one of the following: 1) the first thrust pocket portion 110a and the second journal pocket portion 120b; 2) the second thrust pocket portion 110b and the first journal pocket portion 120a, or 3) only the first thrust pocket portion 110a and the first journal pocket portion 120a.

However, as described above, in consideration of designing according to the flow rate and / or friction, it is preferable that the fluid flows only in the second thrust pocket portion 110b and the second journal pocket portion 120b during high-speed rotation .

On the other hand, in the case of low-speed rotation requiring high cutting load and high rigidity, the first thrust pocket portion 110a, the second thrust pocket portion 110b, the first journal pocket portion 120a and the second journal pocket portion 120b Are preferably simultaneously driven.

The double row hydrostatic pressure bearing 100 according to the embodiment has a rotational speed (rpm) of the rotating body 11 and a single hydrostatic bearing, in which the pockets according to the prior art are formed small, 1) the flow rate, 2) the rate of temperature rise, 3) the load capacity, or 4) the stiffness of the fluid is significantly reduced.

Here, the flow rate refers to the flow rate of oil flowing through the pocket. The oil flowing through the pocket is recovered and circulated by the pump. As the flow rate increases, the main shaft may be locked. If the main shaft is locked, there may be problems such as increase in resistance to rotation of the main shaft, so the smaller the flow rate, the better.

That is, the reciprocating hydrostatic pressure bearing 100 according to the embodiment can control the flow rate according to the rotational speed of the rotating body 11, thereby realizing excellent bearing.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined by the appended claims. Range and its equivalent range.

10: Machine tool 11: Rotor (spindle)
12: Fixture (housing) 100: Hydrostatic bearing
110: first pocket portion 110a: first thrust pocket portion
110b: second thrust pocket portion 120: second pocket portion
120a: first journal pocket part 120b: second journal pocket part
130: Euro

Claims (16)

Wherein at least two annular pockets formed on a contact surface of the rotating body or the fixing body are disposed between the rotating body and the holding body for holding the rotating body.
The method according to claim 1,
The hydrostatic bearing is formed on a contact surface of the fixture,
A first thrust pocket portion formed to be spaced apart from the rotating body; and a second thrust pocket portion formed between the rotating body and the first thrust pocket portion.
3. The method of claim 2,
Wherein the first thrust pocket portion and the second thrust pocket portion each include four pockets formed at regular intervals.
3. The method of claim 2,
Wherein the first thrust pocket portion has a longer radial length than the second thrust pocket portion.
3. The method of claim 2,
Wherein the first thrust pocket portion and the second thrust pocket portion comprise:
The fluid is supplied only to one of the first thrust pocket portion and the second thrust pocket portion when the rotating body rotates at a speed higher than a predetermined speed,
Wherein the fluid is supplied to the first thrust pocket portion and the second thrust pocket portion when the rotor rotates at a predetermined speed or lower.
6. The method of claim 5,
Wherein the fluid is supplied to the second thrust pocket portion when the rotor rotates at a speed higher than a predetermined speed.
The method according to claim 1,
The hydrostatic pressure bearing is formed on a contact surface of the rotating body,
A first journal pocket portion formed to be spaced apart from an end of the rotating body; and a second journal pocket portion formed between the end of the rotating body and the first journal pocket portion.
8. The method of claim 7,
Wherein the first journal pocket portion and the second journal pocket portion each include four pockets formed at regular intervals.
8. The method of claim 7,
Wherein the first journal pocket portion has a longer axial length than the second journal pocket portion.
8. The method of claim 7,
Wherein the first journal pocket portion and the second journal pocket portion are formed in a substantially rectangular shape,
The fluid is supplied only to one of the first journal pocket portion and the second journal pocket portion when the rotating body rotates at a speed higher than a predetermined speed,
Wherein the fluid is supplied to the first journal pocket portion and the second journal pocket portion when the rotating body rotates at a predetermined speed or lower.
11. The method of claim 10,
Wherein the fluid is supplied to the second journal pocket portion when the rotating body rotates at a speed higher than a predetermined speed.
A rotating body disposed between the rotating body and the holding body for receiving the rotating body,
A first thrust pocket portion formed on a contact surface of the fixed body and spaced apart from the rotating body;
A second thrust pocket portion formed on a contact surface of the fixture body and formed between the rotator and the first thrust pocket portion;
A first journal pocket formed on a contact surface of the rotating body and spaced apart from a distal end of the rotating body; And
And a second journal pocket formed on a contact surface of the rotating body and formed between the end of the rotating body and the first journal pocket.
13. The method of claim 12,
Wherein the first thrust pocket portion has a longer length in the radial direction than the second thrust pocket portion,
Wherein the first journal pocket portion has a longer axial length than the second journal pocket portion.
13. The method of claim 12,
The first thrust pocket portion, the second thrust pocket portion, the first journal pocket portion, and the second journal pocket portion,
Wherein fluid is supplied to one of the first thrust pocket portion and the second thrust pocket portion when the rotating body rotates at a speed higher than a predetermined speed and the fluid is supplied to one of the first journal pocket portion and the second journal pocket portion One of which is supplied with fluid,
Wherein the fluid is supplied to the first thrust pocket portion, the second thrust pocket portion, the first journal pocket portion, and the second journal pocket portion when the rotor rotates at a predetermined speed or lower.
15. The method of claim 14,
Wherein the fluid is supplied to the second thrust pocket portion and the second journal pocket portion when the rotor rotates at a speed higher than a predetermined speed.
A spindle as a rotating body;
A housing for holding the spindle; And
A machine tool comprising the hydraulic pressure bearing according to any one of claims 1 to 15.
KR1020150113819A 2015-08-12 2015-08-12 Hydrostatic bearing and machine tool having the same KR101727813B1 (en)

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KR1020150113819A KR101727813B1 (en) 2015-08-12 2015-08-12 Hydrostatic bearing and machine tool having the same

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KR101727813B1 KR101727813B1 (en) 2017-04-17

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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100359185B1 (en) 1997-04-24 2003-03-17 시게이트 테크놀로지 엘엘씨 Magnetic disc storage system and a hydrodynamic fluid bearing system for the same

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007002862A (en) * 2005-06-21 2007-01-11 Olympus Corp Hydrostatic bearing
JP5602122B2 (en) * 2011-12-13 2014-10-08 日立Ｇｅニュークリア・エナジー株式会社 Slide bearing and pump device using the same

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100359185B1 (en) 1997-04-24 2003-03-17 시게이트 테크놀로지 엘엘씨 Magnetic disc storage system and a hydrodynamic fluid bearing system for the same

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