WO2007119428A1 - 動圧軸受装置 - Google Patents
動圧軸受装置 Download PDFInfo
- Publication number
- WO2007119428A1 WO2007119428A1 PCT/JP2007/055559 JP2007055559W WO2007119428A1 WO 2007119428 A1 WO2007119428 A1 WO 2007119428A1 JP 2007055559 W JP2007055559 W JP 2007055559W WO 2007119428 A1 WO2007119428 A1 WO 2007119428A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- bearing
- housing
- end surface
- bearing sleeve
- shaft member
- Prior art date
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Classifications
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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
- F16C17/00—Sliding-contact bearings for exclusively rotary movement
- F16C17/26—Systems consisting of a plurality of sliding-contact bearings
-
- 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
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/72—Sealings
- F16C33/74—Sealings of sliding-contact bearings
- F16C33/741—Sealings of sliding-contact bearings by means of a fluid
- F16C33/743—Sealings of sliding-contact bearings by means of a fluid retained in the sealing gap
- F16C33/745—Sealings of sliding-contact bearings by means of a fluid retained in the sealing gap by capillary action
-
- 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
- F16C17/00—Sliding-contact bearings for exclusively rotary movement
- F16C17/10—Sliding-contact bearings for exclusively rotary movement 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
- F16C17/00—Sliding-contact bearings for exclusively rotary movement
- F16C17/10—Sliding-contact bearings for exclusively rotary movement for both radial and axial load
- F16C17/102—Sliding-contact bearings for exclusively rotary movement for both radial and axial load with grooves in the bearing surface to generate hydrodynamic pressure
- F16C17/107—Sliding-contact bearings for exclusively rotary movement for both radial and axial load with grooves in the bearing surface to generate hydrodynamic pressure with at least one surface for radial load and at least one surface for axial load
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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
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/02—Parts of sliding-contact bearings
- F16C33/04—Brasses; Bushes; Linings
- F16C33/06—Sliding surface mainly made of metal
- F16C33/10—Construction relative to lubrication
- F16C33/1025—Construction relative to lubrication with liquid, e.g. oil, as lubricant
- F16C33/106—Details of distribution or circulation inside the bearings, e.g. details of the bearing surfaces to affect flow or pressure of the liquid
- F16C33/107—Grooves for generating pressure
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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
- F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
- F16C35/02—Rigid support of bearing units; Housings, e.g. caps, covers in the case of sliding-contact bearings
-
- 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
- F16C2370/00—Apparatus relating to physics, e.g. instruments
- F16C2370/12—Hard disk drives or the like
-
- 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
- F16C43/00—Assembling bearings
- F16C43/02—Assembling sliding-contact bearings
Definitions
- the present invention relates to a hydrodynamic bearing device.
- a dynamic pressure bearing device supports a shaft member in a non-contact manner by a dynamic pressure action of a fluid generated in a bearing gap.
- This type of bearing device has features such as high-speed rotation, high rotation accuracy, and low noise. More specifically, this type of bearing device is used as a bearing device for motors installed in various electrical equipment including information equipment. Magnetic disk devices such as HDD, optical disk devices such as CD-ROM, CD-R / RW, DVD-ROMZRAM, magneto-optical disk devices such as MD and MO, etc. as a spindle motor bearing device or laser beam printer ( It is suitably used as a motor bearing device such as a polygon scanner motor (LBP), a color wheel motor for a projector, and a fan motor.
- LBP polygon scanner motor
- color wheel motor for a projector and a fan motor.
- both a radial bearing portion that supports a shaft member in a radial direction and a thrust bearing portion that supports a thrust direction in the thrust direction are hydrodynamic bearings. May be configured.
- a radial bearing portion in this type of dynamic pressure bearing device for example, a dynamic pressure groove as a dynamic pressure generating portion is provided on either the inner peripheral surface of the bearing sleeve or the outer peripheral surface of the shaft member facing the bearing sleeve. It is known that a radial bearing gap is formed between both surfaces (see, for example, Patent Document 1).
- a plurality of bearing sleeves may be provided, and these may be arranged at a plurality of locations separated in the axial direction. (For example, see Patent Document 2).
- Patent Document 1 Japanese Patent Laid-Open No. 2003-239951
- Patent Document 2 Japanese Patent No. 3602707
- each bearing sleeve is fixed to the inner periphery of the housing by bonding, press fitting, or the like.
- bonding fixing a lubricating fluid formed on the outer peripheral surface side of the bearing sleeve Since it is necessary to perform the bonding work with care so that the fluid passages are not blocked by the adhesive, the fixing work takes time, and in the case of press-fitting fixing, the bearing sleeve is used to obtain sufficient fixing force.
- a first problem of the present invention is to provide a hydrodynamic bearing device that is easy to manufacture and fix a bearing sleeve having a high load capacity with respect to a moment load and that can secure a necessary fixing force.
- the second problem of the present invention is that it is easy to manufacture and fix a bearing sleeve having a high load capacity with respect to moment load, and does not reduce the inner diameter of the bearing sleeve. It is to provide a hydrodynamic bearing device that can secure the necessary fixing force. Furthermore, even when the housing linear expansion coefficient is larger than that of the bearing sleeve, the thermal contraction of the two when the temperature is lowered. It is an object of the present invention to provide a hydrodynamic bearing device capable of preventing or suppressing the reduction of the inner diameter of the bearing sleeve due to the difference and the reduction of the radial bearing clearance due to the difference.
- the first means made to solve the first problem is: knitting, uzing, a bearing sleeve housed in the housing, a shaft member inserted in the inner periphery of the bearing sleeve, A hydrodynamic bearing device including a radial bearing portion that supports a shaft member in a radial direction without contact by a hydrodynamic action of a lubricating fluid generated in a radial bearing gap between an inner circumferential surface of the bearing sleeve and an outer circumferential surface of the shaft member.
- a plurality of bearing sleeves are arranged apart from each other in the axial direction, a spacer portion is provided between the bearing sleeves spaced apart in the axial direction, and the spacer portion is fixedly provided to the housing.
- the sleeve provides a configuration in which an end surface facing the end surface of the spacer portion is bonded and fixed to the spacer portion.
- the plurality of bearing sleeves are provided and are separated in the axial direction and arranged at a plurality of locations. Therefore, the span between the radial bearing portions is increased to cope with the moment load. The load capacity can be increased and the manufacture of the bearing sleeve can be facilitated. Also, the bearing sleeve is fixed to the end surface of the spacer portion at the end surface facing the end surface of the spacer portion that is fixedly attached to the sleeve and the uging. Even when forming a fluid passage for the fluid, there is no need to worry about the fluid passage being blocked by the adhesive, and the necessary fixing force of the bearing sleeve can be secured.
- the second means made to solve the second problem is: knitting, uzing, a bearing sleeve housed in the housing, a shaft member inserted in the inner periphery of the bearing sleeve, A hydrodynamic bearing device including a radial bearing portion that supports a shaft member in a radial direction without contact by a hydrodynamic action of a lubricating fluid generated in a radial bearing gap between an inner circumferential surface of the bearing sleeve and an outer circumferential surface of the shaft member.
- a plurality of bearing sleeves are arranged apart from each other in the axial direction, a spacer portion is provided between the bearing sleeves spaced apart in the axial direction, and the spacer portion is fixedly provided to the housing.
- the sleeve is inserted in the inner periphery of the housing with a gap, and A configuration is provided in which the end face opposite to the end face of the spacer section is bonded and fixed to the spacer section.
- the span between the radial bearing portions is increased to cope with the moment load.
- the load capacity can be increased and the manufacture of the bearing sleeve can be facilitated.
- the bearing sleeve is inserted with a gap in the inner periphery of the sleeve and the wing, and the end surface of the spacer portion that is opposed to the end surface of the spacer portion that is fixedly attached to the sleeve and the wing.
- the spacer part is formed integrally with the housing in a configuration in which the spacer part is fixed to the nose and the housing. And a structure in which a separate spacer portion is fixed to the housing by an appropriate means such as bonding, press-fitting, press-fitting adhesion (combined use of press-fitting gluing), welding, or welding.
- a concave adhesive reservoir is provided on at least one of the end surface of the bearing sleeve and the end surface of the spacer portion. A part of the adhesive filled or applied between the end surface of the bearing sleeve and the end surface of the spacer portion is captured by the adhesive reservoir, so that the excess adhesive flows to the inner diameter side, and the bearing sleeve It is possible to prevent the phenomenon of turning around to the inner peripheral surface side (radial bearing gap side).
- the spacer portion can be provided with fluid passages opened on both sides in the axial direction. Further, the fluid passage of the spacer portion can be communicated with an axial fluid passage provided between the inner peripheral surface of the housing and the outer peripheral surface of the bearing sleeve. These fluid passages are used to flow and circulate the lubricating fluid inside the housing. It becomes a circulation passage. The lubricating fluid flows and circulates through this circulation path, so that the pressure chan- nel of the lubricating fluid filled in the housing internal space including the bearing clearance is maintained, and at the same time, bubbles accompanying the generation of local negative pressure are generated.
- the lubricating fluid leaks due to generation of bubbles or bubbles, problems such as vibrations can be solved.
- the bubbles are discharged to the open air side when circulating along with the lubricating fluid. Therefore, the adverse effects due to air bubbles can be more effectively prevented.
- the shaft member is provided with a protruding portion protruding to the outer diameter side, and a thrust bearing gap is generated between the end surface of the protruding portion and the end surface of the bearing sleeve.
- a thrust bearing portion that supports the shaft member in a non-contact manner in the thrust direction by the dynamic pressure action of the lubricating fluid may be provided.
- the protrusion may be formed integrally with the shaft member, or may be fixed to the shaft member.
- the dynamic pressure generating means (dynamic pressure groove or the like) of the thrust bearing portion may be formed on one of the end surface of the protruding portion and the end surface of the bearing sleeve.
- a seal space may be formed on the outer peripheral side of the protruding portion of the shaft member.
- This seal space has a function of absorbing a volume change (expansion and contraction) caused by a temperature change of the lubricating fluid filled in the housing internal space, a so-called buffer function.
- the housing may be a molded product of a molten material.
- the material of the housing may be either resin or metal.
- the housing is made of resin, for example, injection molding such as thermoplastic resin can be employed.
- the housing is made of metal, for example, die casting or injection molding (so-called MIM method or thixo molding method) of aluminum alloy, magnesium alloy, stainless steel or the like can be employed.
- the hydrodynamic bearing device according to the first means is suitable for a motor incorporated in a disk drive device such as an HDD, particularly a server HDD.
- the dynamic pressure bearing device according to the second means is suitable for a motor incorporated in a disk drive device such as an HDD.
- the bearing sleeve has a high load capacity with respect to a moment load. It is possible to provide a hydrodynamic bearing device that is easy to manufacture and fix, and that can secure a necessary fixing force.
- the second means it is easy to manufacture and fix a bearing sleeve having a high load capacity against a moment load, and it is necessary to reduce the inner diameter of the bearing sleeve. It is possible to provide a hydrodynamic bearing device capable of securing a fixing force. In addition, even when the linear expansion coefficient of gnosing and waging is larger than that of the bearing sleeve, the inner diameter of the bearing sleeve is reduced due to the thermal contraction difference between the two when the temperature is lowered, thereby reducing the radial bearing clearance. Can be prevented or suppressed.
- FIG. 1 is a cross-sectional view of a fluid dynamic bearing device according to a first embodiment.
- FIG. 2 Top view showing the bearing sleeve fixed to the housing ⁇ Fig. 2 (a) ⁇ , sectional view ⁇ Fig.
- FIG. 3 is an enlarged sectional view showing an upper part of the housing.
- FIG. 4 is an enlarged cross-sectional view showing a peripheral portion of an adhesive fixing portion between a bearing sleeve and a spacer portion.
- FIG. 5 is a cross-sectional view of a fluid dynamic bearing device according to a second embodiment.
- FIG. 6 is a cross-sectional view of a fluid dynamic bearing device according to a third embodiment.
- FIG. 7 is a cross-sectional view of a fluid dynamic bearing device according to a fourth embodiment.
- FIG. 8 Top view showing the bearing sleeve fixed to the housing ⁇ Fig. 8 (a) ⁇ , sectional view ⁇ Fig.
- FIG. 9 is an enlarged sectional view showing an upper part of the housing.
- FIG. 10 is an enlarged cross-sectional view showing a peripheral portion of an adhesive fixing portion between a bearing sleeve and a spacer portion.
- FIG. 11 is a cross-sectional view of a fluid dynamic bearing device according to a fifth embodiment.
- FIG. 12 is a cross-sectional view of a fluid dynamic bearing device according to a sixth embodiment.
- FIG. 1 shows a hydrodynamic bearing device (fluid hydrodynamic bearing device) 1 according to a first embodiment.
- the hydrodynamic bearing device 1 supports rotation of a spindle shaft in, for example, a motor incorporated in an HDD, particularly a server HDD.
- the hydrodynamic bearing device 1 includes a housing 2 and a plurality of, for example, two bearing sleeves 3 and 4 accommodated in the housing 2 at positions spaced apart from each other in the axial direction.
- the shaft member 5 inserted around the circumference is configured as a main component.
- the first radius is formed between the inner peripheral surface 3a of the bearing sleeve 3 and the outer peripheral surface 5a of the shaft member 5.
- Al bearing portion Rl is provided, and second radial bearing portion R2 is provided between inner peripheral surface 4a of bearing sleeve 4 and outer peripheral surface 5a of shaft member 5.
- the first thrust bearing portion T1 is provided between the upper end surface 3b of the bearing sleeve 3 and the lower end surface 6b of the seal member 6, and the lower end surface 4b of the bearing sleeve 4 and the seal member 7 are
- a second thrust bearing portion T2 is provided between the upper end surface 7b.
- the end of the shaft member 5 protrudes from the housing 2, and the explanation will be made with the side (upper side in the drawing) as the upper side and the opposite side as the lower side.
- the nozzle 2 is integrally formed by, for example, injection molding a resin material, and has inner peripheral surfaces 2a and 2b in which the bearing sleeves 3 and 4 are accommodated, and an inner diameter larger than the inner peripheral surfaces 2a and 2b. And a spacer portion 2c protruding to the side.
- the inner peripheral surfaces 2a and 2b are located at positions spaced apart from each other in the axial direction corresponding to the arrangement positions of the bearing sleeves 3 and 4, and the region between the inner peripheral surfaces 2a and 2b is the spacer portion 2c. Yes.
- the inner peripheral surfaces 2a and 2b have the same diameter.
- the spacer portion 2c is provided with an axial fluid passage 2cl, and the fluid passage 2cl opens to the upper end surface 2c2 and the lower end surface 2c3 of the spacer portion 2c, respectively.
- a plurality of, for example, three fluid passages 2cl are formed and arranged at equal intervals around the circumference.
- large-diameter portions 2d and 2e are provided at both ends of the housing 2, and the large-diameter portions 2d and 2e are connected to the inner peripheral surfaces 2a and 2b via step surfaces 2f and 2g, respectively.
- the fluid passage 2cl of the spacer portion 2c may be formed by forming a hole after forming the housing 2, but in order to reduce the processing man-hour and thereby reduce the manufacturing cost, It is preferable to mold the housing 2 at the same time. This can be performed by providing a forming pin corresponding to the shape of the fluid passage 2cl in the forming die for forming the nozzle 2 and the wozing 2.
- the cross-sectional shape of the fluid passage 2cl is not limited to a circular shape, and may be a non-circular shape (an elliptical shape, a polygonal shape, etc.). Further, the cross-sectional area of the fluid passage 2cl need not be constant in the axial direction. For example, there may be a portion having a relatively large cross-sectional area and a portion having a relatively small cross-sectional area.
- the resin forming Uzing 2 is mainly thermoplastic resin, for example, as amorphous resin, polysulfone (PSU), polyethersulfone (PES), polysulfone (PPSU), Crystalline resin such as polyetherimide (PEI), liquid crystal polymer (LCP), polyetheretherketone (PEEK), polybutylene terephthalate (PBT), polyphenolsal Fido (PPS) etc. can be used.
- PSU polysulfone
- PES polyethersulfone
- PPSU polysulfone
- Crystalline resin such as polyetherimide (PEI), liquid crystal polymer (LCP), polyetheretherketone (PEEK), polybutylene terephthalate (PBT), polyphenolsal Fido (PPS) etc.
- PES polysulfone
- PES polysulfone
- Crystalline resin such as polyetherimide (PEI), liquid crystal polymer (LCP), polyetheretherketone (PEEK), polybut
- Fibrous or powdery conductive fillers such as fibrous filler, carbon fiber, carbon black, graphite, carbon nanomaterial, and metal powder can be used. These fillers may be used alone or in combination of two or more.
- a resin material in which 2 to 8 wt% of a bon fiber or carbon nanotube as a conductive filler is blended with a liquid crystal polymer (LCP) as a crystalline resin. is used as a material for forming the housing 2.
- the shaft member 5 is made of a metal material such as stainless steel, and has a shaft shape with substantially the same diameter as a whole. Furthermore, in this embodiment, the annular seal members 6 and 7 are fixed to the shaft member 5 by an appropriate fixing means, for example, adhesion or press-fit adhesion (combination of press-fit and adhesion). These seal members 6 and 7 protrude from the outer peripheral surface 5a of the shaft member 5 to the outer diameter side, and are accommodated in the large diameter portions 2d and 2e of the housing 2, respectively. In order to increase the fixing strength by the adhesive, circumferential grooves 5al and 5a2 serving as adhesive reservoirs are provided on the outer peripheral surface 5a of the shaft member 5 serving as a fixing position of the seal members 6 and 7.
- an appropriate fixing means for example, adhesion or press-fit adhesion (combination of press-fit and adhesion).
- These seal members 6 and 7 protrude from the outer peripheral surface 5a of the shaft member 5 to the outer diameter side, and are accommodated in the large
- the seal members 6 and 7 may be formed of a soft metal material such as brass (brass) or other metal materials, or may be formed of a resin material.
- One of the seal members 6 and 7 may be integrally formed with the shaft member 5.
- the shaft member 5 and the assembly having one sealing member force can be composed of a composite of metal and resin.
- the shaft member 5 is made of metal and one seal member is insert-molded with resin.
- the outer peripheral surface 6a of the seal member 6 forms a seal space S1 having a predetermined volume with the large-diameter portion 2d of the housing 2, and the outer peripheral surface 7a of the seal member 7 is the large-diameter portion 2e of the housing 2.
- a seal space S2 having a predetermined volume is formed between the two.
- the outer peripheral surface 6 a of the seal member 6 and the outer peripheral surface 7 a of the seal member 7 are each formed in a tapered surface shape that is gradually reduced in diameter toward the outside of the nosing 2. Therefore, the seal spaces Sl and S2 have a tapered shape that gradually decreases toward the inner side of the housing 2.
- the bearing sleeves 3 and 4 are, for example, porous bodies made of sintered metal, particularly copper as a main component.
- a porous body of sintered metal is formed into a cylindrical shape, and is inserted into the inner peripheral surfaces 2a and 2b of the housing 2, respectively, or press-fitted with a pressure that does not cause deformation of the inner peripheral surfaces 3a and 4a. Yes (light press fit).
- the lower end surface 3c of the bearing sleeve 3 is fixed to the upper end surface 2c2 of the spacer portion 2c with an adhesive Al.
- the lower end surface 3c of the bearing sleeve 3 is provided with a circumferential groove-shaped adhesive reservoir 3cl.
- the surface aperture ratio of the lower end surface 3c of the bearing sleeve 3 is set to be smaller than the surface aperture ratio of the outer peripheral surface 3d, and the surface aperture capacity of the lower end surface 3c of the adhesive sleeve A1 is also lower than that of the bearing sleeve 3. It is preferable to make it so that it enters the inside.
- the concave adhesive reservoir may be provided on the upper end surface 2c2 of the spacer portion 2c, or may be provided on both the lower end surface 3c of the bearing sleeve 3 and the upper end surface 2c2 of the spacer portion 2c. good.
- a circumferential groove-shaped adhesive reservoir 4c 1 is provided on the upper end surface 4c of the bearing sleeve 4, and when a part of the adhesive A2 enters the adhesive reservoir 4cl, the excess adhesive A2 becomes the inner diameter side. This prevents the phenomenon of flowing into the inner peripheral surface 4a side of the bearing sleeve 4 (the radial bearing gap side).
- a plurality of circumferential groove-shaped adhesive reservoirs 4cl may be provided on the upper end surface 4c.
- the concave adhesive reservoir may be provided on the lower end surface 2c3 of the spacer portion 2c, or provided on both the upper end surface 4c of the bearing sleeve 4 and the lower end surface 2c3 of the spacer portion 2c. May be.
- the bearing sleeve 3 serves as a radial bearing surface of the first radial bearing portion R1.
- a herringbone-shaped dynamic pressure groove 3al is formed on the inner peripheral surface 3a, and a herringbone-shaped dynamic pressure groove 3bl is formed on the upper end surface 3b serving as the thrust bearing surface of the first thrust bearing portion Tl.
- An axial groove 3dl is formed on the surface 3d.
- a plurality of, for example, three axial grooves 3dl are formed and arranged at equal intervals around the circumference.
- An axial fluid passage is formed between the axial groove 3dl and the inner peripheral surface 2a of the housing 2.
- the bearing sleeve 4 has a herringbone-shaped dynamic pressure groove 4al formed on the inner peripheral surface 4a which is the radial bearing surface of the second radial bearing portion R2, and becomes the thrust bearing surface of the second thrust bearing portion T2.
- a herringbone-shaped dynamic pressure groove 4b 1 is formed on the lower end surface 4b, and an axial groove 4d 1 is formed on the outer peripheral surface 4d.
- a plurality of, for example, three axial grooves 4dl are formed and arranged at equal intervals around the circumference.
- An axial fluid passage is formed between the axial groove 4 dl and the inner peripheral surface 2 b of the housing 2.
- the bearing sleeve 3 is fixed to the upper end surface 2c2 of the spacer portion 2c with the adhesive A1, and the upper end surface 3b is the upper step surface 2f of the housing 2. It is in a state of protruding by a slight dimension ⁇ 2 from the step surface 2f. This state can be realized by managing the axial dimension of the bearing sleeve 3 and the axial dimension of the inner peripheral surface 2a of the housing 2 (or the axial dimension of the spacer portion 2c).
- the bearing sleeve 3 when the upper end surface 3b of the bearing sleeve 3 is projected from the step surface 2f by a dimension ⁇ 2, the axial dimension between the lower end surface 6b of the seal member 6 and the step surface 2f is The thrust bearing clearance T1 of the first thrust bearing portion T1 is larger than the first thrust bearing portion T1.
- This dynamic pressure bearing device 1 is prepared, for example, in the following process.
- the adhesive A 1 is applied to the lower end surface 3c of the bearing sleeve 3 or the upper end surface 2c2 of the spacer portion 2c, and then the bearing sleeve 3 is inserted into the inner peripheral surface 2a of the nosing 2 to obtain the bearing.
- the lower end surface 3c of the sleeve 3 is brought into contact with the upper end surface 2c2 of the spacer portion 2c through the adhesive A1.
- the position of the axial groove 3dl of the bearing sleeve 3 is aligned with the position of the fluid passage 2cl of the spacer 2c.
- the fluid passage formed by the axial groove 3dl communicates with the fluid passage 2c 1 of the spacer portion 2c.
- an adhesive is applied to the upper end surface 4c of the bearing sleeve 4 or the lower end surface 2c3 of the spacer portion 2c.
- A2 is applied, the bearing sleeve 4 is inserted into the inner peripheral surface 2b of the nosing 2 and the upper end surface 4c of the bearing sleeve 4 is brought into contact with the lower end surface 2c3 of the spacer 2c through the adhesive A2. .
- the position of the axial groove 4dl of the bearing sleeve 4 is matched with the position of the fluid passage 2cl of the spacer 2c.
- the fluid passage 2cl communicates with the fluid passage 2cl of the fluid passage spacer portion 2c formed by the axial groove 4dl.
- the shaft member 5 is inserted into the inner peripheral surfaces 3a and 4a of the bearing sleeves 3 and 4 and the inner peripheral surface 2c4 of the spacer portion 2c, and the seal members 6 and 7 are fixed to predetermined positions of the shaft member 5.
- One of the seal members 6 and 7 may be fixed to the shaft member 5 in advance before insertion, or may be integrally formed on the shaft member 5.
- the internal space of the housing 2 sealed with the seal members 6 and 7 includes the internal pores of the bearing sleeves 4 and 5 (internal pores of the porous body tissue),
- lubricating oil is filled as a lubricating fluid.
- the lubricating oil can be filled, for example, by immersing the hydrodynamic bearing device 1 that has been assembled in the lubricating oil in a vacuum chamber and then releasing it to atmospheric pressure.
- the inner peripheral surface 3a of the bearing sleeve 3 and the inner peripheral surface 4a of the bearing sleeve 4 face the outer peripheral surface 5a of the shaft member 5 with a radial bearing gap therebetween.
- the clearance between the inner peripheral surface 2c4 of the spacer 2c and the outer peripheral surface 5a of the shaft member 5 is larger than the radial bearing clearance.
- the upper end surface 3b of the bearing sleeve 3 is opposed to the lower end surface 6b of the seal member 6 via a thrust bearing gap, and the lower end surface 4b of the bearing sleeve 4 is opposed to the upper end surface 7b of the seal member 7 and the thrust bearing gap. Opposite through.
- the seal spaces Sl and S2 formed on the outer peripheral surface 6a side of the seal member 6 and the outer peripheral surface 7a side of the seal member 7 are gradually directed toward the inner side of the housing 2 Due to the reduced taper shape, the lubricating oil in both seal spaces Sl and S2 is narrowed by the pull-in action by capillary force and the pull-in action by centrifugal force during rotation, that is, the housing 2 It is drawn toward the inside. As a result, leakage of the lubricating oil from the inside of the housing 2 is effectively prevented.
- seal spaces Sl, S 2 have a buffer function that absorbs the volume change accompanying the temperature change of the lubricant filled in the inner space of the housing 2, and within the range of the assumed temperature change, the lubricant oil The oil level is always in the seal space Sl, S2.
- a fluid passage formed by the axial groove 3dl of the bearing sleeve 3, a fluid passage formed by the axial groove 4dl of the bearing sleeve 4, a fluid passage 2cl of the spacer portion 2c, and each bearing gap The radial bearing clearance of the first radial bearing portion R1 and the second radial bearing portion R2, the thrust bearing clearance of the first thrust bearing portion T1 and the second thrust bearing portion T2, and the inner peripheral surface 2c4 of the spacer portion 2c and the shaft
- a continuous circulation passage is formed inside the housing 2 by a gap between the member 5 and the outer peripheral surface 5a.
- the lubricating oil filled in the internal space of the housing 2 flows and circulates through the circulation passage, so that the pressure balance of the lubricating oil is maintained, and at the same time, bubbles are generated due to the generation of local negative pressure. In addition, leakage of lubricating oil and vibration due to the generation of bubbles are prevented.
- one end of the fluid passage formed by the axial groove 3dl of the bearing sleeve 3 and one end of the fluid passage formed by the axial groove 4dl of the bearing sleeve 4 are respectively sealed spaces Sl, Leads to S2. Therefore, even if bubbles are mixed in the lubricating oil for some reason, the bubbles are discharged to the open air side when circulating along with the lubricating oil, so that the adverse effects of the bubbles can be prevented more effectively.
- FIG. 5 shows a fluid dynamic bearing device 11 according to the second embodiment.
- the hydrodynamic bearing device 11 is different from the hydrodynamic bearing device 1 according to the first embodiment described above in that the spacer portion 2c is formed of a sleeve-like member separate from the housing 2, and this spacer Spacer part 2c of housing 2 The point is that it is fixed to the inner peripheral surface 2a by an adversary means such as adhesion, press-fitting, and press-fitting adhesion.
- the fluid passage 2cl is formed in an axial groove shape on the outer peripheral surface of the spacer portion 2c.
- the spacer portion 2c can be formed of the same or different grease as the housing 2 or a metal material.
- the inner peripheral surface 2a of the housing 2 has a straight shape in the axial direction over the mounting portion of the bearing sleeve 3 from the mounting portion force of the bearing sleeve 3, and the hydrodynamic bearing device of the first embodiment Compared to 1, the shape of the housing 2 is simplified. Since other matters are the same as those in the first embodiment, substantially the same members and parts are denoted by the same reference numerals, and redundant description is omitted.
- FIG. 6 shows a fluid dynamic bearing device 21 according to a third embodiment.
- This hydrodynamic bearing device 21 is different from the hydrodynamic bearing device 1 according to the first embodiment described above in that the inner peripheral surfaces 2a and 2b of the housing 2 have uniform diameters and extend to the end surface of the housing 2, respectively.
- the seal members 6 and 7 have a relatively small diameter.
- the shape of the housing 2 can be simplified and the diameter can be reduced. Since other matters are the same as those in the first embodiment, substantially the same members and parts are denoted by the same reference numerals, and redundant description is omitted.
- herringbone-shaped dynamic pressure grooves are illustrated as the dynamic pressure generating means of the radial bearing portions Rl, R2 and the thrust bearing portions Tl, ⁇ 2.
- a dynamic pressure groove having a snail shape or other shapes may be used.
- a loose step bearing can be a multi-arc bearing as a means for generating dynamic pressure.
- FIG. 7, FIG. 8, FIG. 9 and FIG. 10 show a hydrodynamic bearing device (fluid hydrodynamic bearing device) 31 according to the fourth embodiment, and FIG. 1, according to the first embodiment described above, These correspond to Fig. 2, Fig. 3 and Fig. 4, respectively.
- the hydrodynamic bearing device 31 supports the rotation of the spindle shaft in, for example, a motor incorporated in the HDD.
- the hydrodynamic bearing device 31 according to the fourth embodiment differs from the hydrodynamic bearing device 1 according to the first embodiment described above in that, for example, a porous body made of sintered metal, particularly copper, is mainly used.
- Bearing sleeves 3 and 4 formed into a cylindrical shape with a porous body of sintered metal as a component, respectively, in that they are inserted into the inner peripheral surfaces 2a and 2b of the housing 2 with slight radial gaps Cl and C2, respectively. is there.
- These radial gaps Cl and C2 are, for example, within the range of the expected temperature change, The size is set so that the entire amount of thermal contraction difference due to the difference in coefficient of linear expansion with the bearing sleeves 3 and 4 made of metal can be absorbed.
- the radial gaps C1 and C2 may be set to the same size or different sizes. Since other matters are the same as in the first embodiment, substantially the same members and parts are denoted by the same reference numerals, and redundant description is omitted.
- FIG. 11 shows a fluid dynamic bearing device 41 according to a fifth embodiment.
- This hydrodynamic bearing device 41 is different from the hydrodynamic bearing device 31 according to the fourth embodiment described above in that the spacer portion 2 c is formed of a sleeve-like member that is separate from the nosing 2.
- the spacer 2c is fixed to the inner peripheral surface 2a of the nosing 2 by an adversary means such as adhesion, press-fitting, and press-fitting.
- the fluid passage 2cl is formed in an axial groove shape on the outer peripheral surface of the spacer portion 2c.
- the spacer portion 2 c can be formed of the same or different grease as the housing 2 or a metal material.
- the inner peripheral surface 2a of the housing 2 has a straight shape in the axial direction from the mounting portion of the bearing sleeve 3 to the mounting portion of the bearing sleeve 4, and is provided in the hydrodynamic bearing device 31 of the fourth embodiment.
- the shape of the housing 2 is simplified. Since other matters are the same as those in the fourth embodiment, substantially the same members and parts are denoted by the same reference numerals, and redundant description is omitted.
- FIG. 12 shows a fluid dynamic bearing device 51 according to a sixth embodiment.
- the hydrodynamic bearing device 51 is different from the hydrodynamic bearing device 31 according to the fourth embodiment described above in that the inner peripheral surfaces 2a and 2b of the housing 2 have uniform diameters and extend to the end surface of the housing 2. Accordingly, the sealing members 6 and 7 have a relatively small diameter.
- the shape of the housing 2 can be simplified and the diameter can be reduced. Since other matters are the same as those in the fourth embodiment, substantially the same members and parts are denoted by the same reference numerals, and redundant description is omitted.
- herringbone-shaped dynamic pressure grooves are illustrated as dynamic pressure generating means for the radial bearing portions Rl, R2 and the thrust bearing portions Tl, ⁇ 2.
- a dynamic pressure groove having a snail shape or other shapes may be used.
- a loose step bearing can be a multi-arc bearing as a means for generating dynamic pressure.
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/294,331 US8104964B2 (en) | 2006-03-27 | 2007-03-19 | Fluid dynamic bearing unit |
KR1020087023413A KR101321382B1 (ko) | 2006-03-27 | 2007-03-19 | 동압 베어링 장치 |
CN200780011272XA CN101410637B (zh) | 2006-03-27 | 2007-03-19 | 动压轴承装置 |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006086359A JP4855117B2 (ja) | 2006-03-27 | 2006-03-27 | 動圧軸受装置 |
JP2006086371A JP2007263176A (ja) | 2006-03-27 | 2006-03-27 | 動圧軸受装置 |
JP2006-086359 | 2006-03-27 | ||
JP2006-086371 | 2006-03-27 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007119428A1 true WO2007119428A1 (ja) | 2007-10-25 |
Family
ID=38609218
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2007/055559 WO2007119428A1 (ja) | 2006-03-27 | 2007-03-19 | 動圧軸受装置 |
Country Status (3)
Country | Link |
---|---|
US (1) | US8104964B2 (ja) |
KR (1) | KR101321382B1 (ja) |
WO (1) | WO2007119428A1 (ja) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2011257721A (ja) * | 2010-06-07 | 2011-12-22 | Samsung Electro-Mechanics Co Ltd | スキャナモーター |
CN117145789A (zh) * | 2023-09-26 | 2023-12-01 | 肇庆晟辉电子科技有限公司 | 风机用中管和长寿命高转速滚珠风机 |
Citations (3)
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JPH10318250A (ja) * | 1997-05-22 | 1998-12-02 | Sony Corp | 流体軸受と流体軸受の製造方法 |
JPH11155254A (ja) * | 1997-11-21 | 1999-06-08 | Tokyo Parts Ind Co Ltd | 動圧軸受モータ |
JP2005163903A (ja) * | 2003-12-02 | 2005-06-23 | Ntn Corp | 動圧軸受装置 |
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Publication number | Priority date | Publication date | Assignee | Title |
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US4254961A (en) * | 1979-04-30 | 1981-03-10 | Litton Systems, Inc. | Seal for fluid bearings |
US4965476A (en) * | 1989-04-20 | 1990-10-23 | Conner Peripherals, Inc. | Stabilized disk drive spin motor |
US5683183A (en) * | 1995-09-26 | 1997-11-04 | Nsk Ltd. | Spindle device and bearing device therefor |
US6250807B1 (en) * | 1998-09-10 | 2001-06-26 | Ntn Corporation | Hydrodynamic type bearing and hydrodynamic type bearing unit |
JP2001268875A (ja) * | 2000-03-16 | 2001-09-28 | Minebea Co Ltd | スピンドルモータ |
JP4216509B2 (ja) | 2002-02-20 | 2009-01-28 | Ntn株式会社 | 動圧軸受装置の製造方法 |
JP4159332B2 (ja) * | 2002-04-05 | 2008-10-01 | Ntn株式会社 | 動圧軸受装置 |
KR100968163B1 (ko) * | 2002-04-23 | 2010-07-06 | 엔티엔 가부시키가이샤 | 유체 베어링 장치 |
US6948852B2 (en) * | 2002-07-15 | 2005-09-27 | Minebea Co., Ltd. | Hydrodynamic bearing, spindle motor and hard disk drive |
JP4236891B2 (ja) * | 2002-09-26 | 2009-03-11 | Ntn株式会社 | 動圧軸受装置 |
DE20219216U1 (de) | 2002-12-12 | 2004-03-04 | Minebea Co., Ltd., Kitasaku | Spindelmotor für Festplattenlaufwerke mit hydrodynamischer Lageranordnung |
JP2005221029A (ja) * | 2004-02-06 | 2005-08-18 | Sony Corp | 軸受ユニット、軸受ユニットを有するモータ及び電子機器 |
JP2006064171A (ja) * | 2004-07-28 | 2006-03-09 | Minebea Co Ltd | 流体動圧軸受、該流体動圧軸受を備えたスピンドルモータ並びに記録ディスク駆動装置 |
TWI290790B (en) * | 2005-09-30 | 2007-12-01 | Delta Electronics Inc | Motor and bearing structure thereof |
JP2007162759A (ja) * | 2005-12-09 | 2007-06-28 | Matsushita Electric Ind Co Ltd | 動圧流体軸受装置、モータ、記録ディスク駆動装置、組み立て用治具 |
JP5154057B2 (ja) * | 2006-10-27 | 2013-02-27 | Ntn株式会社 | 動圧軸受装置 |
-
2007
- 2007-03-19 KR KR1020087023413A patent/KR101321382B1/ko active IP Right Grant
- 2007-03-19 WO PCT/JP2007/055559 patent/WO2007119428A1/ja active Application Filing
- 2007-03-19 US US12/294,331 patent/US8104964B2/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH10318250A (ja) * | 1997-05-22 | 1998-12-02 | Sony Corp | 流体軸受と流体軸受の製造方法 |
JPH11155254A (ja) * | 1997-11-21 | 1999-06-08 | Tokyo Parts Ind Co Ltd | 動圧軸受モータ |
JP2005163903A (ja) * | 2003-12-02 | 2005-06-23 | Ntn Corp | 動圧軸受装置 |
Also Published As
Publication number | Publication date |
---|---|
US8104964B2 (en) | 2012-01-31 |
US20090136165A1 (en) | 2009-05-28 |
KR20080108252A (ko) | 2008-12-12 |
KR101321382B1 (ko) | 2013-10-23 |
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