CN100434737C - Bearing unit and motor and electric apparatus having bearing unit - Google Patents
Bearing unit and motor and electric apparatus having bearing unit Download PDFInfo
- Publication number
- CN100434737C CN100434737C CNB2006100908197A CN200610090819A CN100434737C CN 100434737 C CN100434737 C CN 100434737C CN B2006100908197 A CNB2006100908197 A CN B2006100908197A CN 200610090819 A CN200610090819 A CN 200610090819A CN 100434737 C CN100434737 C CN 100434737C
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- China
- Prior art keywords
- bearing
- housing
- bearing unit
- axle
- rotatingshaft
- 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 - Fee Related
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D25/00—Pumping installations or systems
- F04D25/02—Units comprising pumps and their driving means
- F04D25/06—Units comprising pumps and their driving means the pump being electrically driven
- F04D25/0606—Units comprising pumps and their driving means the pump being electrically driven the electric motor being specially adapted for integration in the pump
- F04D25/0613—Units comprising pumps and their driving means the pump being electrically driven the electric motor being specially adapted for integration in the pump the electric motor being of the inside-out type, i.e. the rotor is arranged radially outside a central stator
- F04D25/062—Details of the bearings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D25/00—Pumping installations or systems
- F04D25/02—Units comprising pumps and their driving means
- F04D25/06—Units comprising pumps and their driving means the pump being electrically driven
- F04D25/0606—Units comprising pumps and their driving means the pump being electrically driven the electric motor being specially adapted for integration in the pump
- F04D25/0613—Units comprising pumps and their driving means the pump being electrically driven the electric motor being specially adapted for integration in the pump the electric motor being of the inside-out type, i.e. the rotor is arranged radially outside a central stator
- F04D25/0626—Details of the lubrication
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/05—Shafts or bearings, or assemblies thereof, specially adapted for elastic fluid pumps
- F04D29/051—Axial thrust balancing
- F04D29/0513—Axial thrust balancing hydrostatic; hydrodynamic thrust bearings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/05—Shafts or bearings, or assemblies thereof, specially adapted for elastic fluid pumps
- F04D29/056—Bearings
- F04D29/057—Bearings hydrostatic; hydrodynamic
Abstract
A bearing unit, including: a shaft; a first radial bearing configured to support the shaft in a circumferential direction; a second radial bearing disposed in a spaced relationship from the first radial bearing in an axial direction of the shaft configured to support the shaft in the circumferential direction; a thrust bearing configured to support one end of the shaft in a thrust direction; a spacer disposed between the first and second radial bearings; a housing in which the first and second radial bearings and the thrust bearing are disposed and which has an enclosed structure except a shaft insertion hole in which the shaft is fitted; and viscous fluid filled in the housing.
Description
Technical field
The present invention relates to a kind of be used to support the rotatingshaft that is used to rotate or be used to support be used for the rotary member that on an axle, rotates bearing unit, and the present invention relates to a kind of motor and electronic equipment with bearing unit.
Background technique
The bearing unit that is used to support the rotatingshaft that is used for rotating thereon as shown in figure 15 is known in the past.
With reference to Figure 15, shown bearing unit 100 is used for supporting the rotatingshaft 101 that is used for rotating thereon.Bearing unit 100 comprises the radial bearing 104 that is used at circumferential upper support rotatingshaft 101, be used at the thrust-bearing 110 of an end of thrust direction upper support rotatingshaft 101 and wherein hold radial bearing 104 and the housing 105 of thrust-bearing 110.
In bearing unit 100, radial bearing 104 with cooperate so that form the lubricant oil of the viscous fluid of dynamic pressure FDB as being filled in the housing 105.The dynamic pressure that is used to produce dynamic pressure produces the inner peripheral surface that groove 111 is formed on the radial bearing 104 that rotatingshaft 101 wherein is installed.
The housing 105 that wherein holds radial bearing 104 and thrust-bearing 110 comprises tubular shell main body 106, bottom closure portion 107 and top enclosed member 108.Bottom closure portion 107 forms main body with housing body 106, so that of closure shell main body 106 is distolateral, and forms an one end side portion.Top enclosed member 108 be arranged on another of housing body 106 distolateral on, housing body 106 is open in this side.
Thrust-bearing 110 forms pivot bearings, and the bearing support of this bearing supporting rotatingshaft 101 divides 102, and this rotatingshaft 101 has the end of locating to form arc or conical in shape on one point.
By radial bearing 104, thrust-bearing 110 and rotatingshaft 101 are connected on the housing body 106, and then top enclosed member 108 is bonded on the housing body 106, form housing 105 with described structure by hermetic unit 121.
In addition, groove 116 bearing support divide 102 and shaft portion main body 103 between be arranged on the rotatingshaft 101.Annular gasket 115 as anti-detachment member is arranged to relativeness with groove 116 on bottom closure portion 107.Pad 115 prevents that rotatingshaft 101 and housing 105 break away from.When the bearing support of pad 115 by rotatingshaft 101 divided 102 to promote, it was out of shape on thrust direction, made bearing support divide 102 to insert and be connected on the groove 116.
By the way, axle mounting hole 109 is formed with slightly the inner diameter greater than the outer diameter of shaft portion main body 103, makes the rotatingshafts 101 that are installed in the mounting hole 109 to rotate, and the inner peripheral surface of not sliding contact axle mounting hole 109.At this moment, an axle mounting hole 109 forms, and makes that have the lubricant oil 113 that is enough to prevent to be filled in the housing 105 is formed between the outer circumferential face of the inner peripheral surface of a mounting hole 109 and shaft portion main body 103 from the gap 112 apart from x of housing 105 internal leakages.
Tapering part 114 is arranged on the outer circumferential face of rotatingshaft 101 with the inner peripheral surface of axle mounting hole 109 with forming relativeness.Tapering part 114 tilts, and makes to form the gap 112 that increases towards housing 105 outsides between the inner peripheral surface of the inner peripheral surface of rotatingshaft 101 and axle mounting hole 109.Tapering part 114 forms pressure gradient in the gap 112 between the inner peripheral surface of outer circumferential face that is formed on rotatingshaft 101 and axle mounting hole 109, so that produce the power that the lubricant oil that is used for filling in the housing 105 is drawn into housing 105 inboards.Because when rotatingshaft 101 rotated, lubricant oil 113 was biased, so that be drawn into housing 105 inboards, the dynamic pressure that lubricant oil 113 enters the radial bearing 104 that is formed by the dynamic pressure FDB reliably produces groove 111, so that produce dynamic pressure.Therefore, realize the stable support of rotatingshaft 101, and can prevent that the lubricant oil 113 of filling in the housing 105 from leaking.
In the bearing unit 100 with structure of describing with reference to Figure 15, rotatingshaft 101 only exposes at the one end on axle mounting hole 109 1 sides, but except the little gap of axle mounting hole 109, covers by housing structure.Therefore, bearing unit 100 can prevent that lubricant oil 113 from leaking into housing 105 outsides.In addition, because only the gap of axle mounting hole 109 forms connected part with the outside, can prevent owing to impact the lubricating oil splash that causes, so that keep lubricant oil reliably.In addition, in bearing unit 100, can prevent that rotatingshaft 101 breaks away from housing 105 by pad 115.
Cutline because bearing unit 100 can keep lubricant oil 113 reliably, and prevents that rotatingshaft 101 breaks away from, and can keep greasy property and rotating property, so that the rotary member that rotatingshaft that supporting is used to rotate or supporting are used for rotating on axle.
For described this bearing unit, need further reduce the situations such as deviation of rotatingshaft, so that improve rotating property.For situations such as the deviation that reduces rotatingshaft so that improve rotating property, need to increase rigidity.To adopt the rigidity of bearing unit in order increasing, for example can to increase the length on the axial direction of the radial bearing that forms this bearing unit.
But in described bearing unit 100, the radial bearing that forms bearing unit is formed by sintered component or similar component, and owing to the casting existence restriction of the relation between diameter and the axial length for bearing unit 100.In this way, there is restriction in bearing unit for the increase of rigidity, and is difficult to reduce the situations such as deflection that rotary member surpasses predetermined condition.
In Japanese patent laid-open NO.2003-130043, disclosed the bearing unit that is similar to here the bearing unit of describing with reference to Figure 15 100.
Summary of the invention
What need is motor and the electronic equipment that the invention provides a kind of bearing unit and comprise bearing unit, and the rigidity of the axle that can raise thus so that restrain the deflection of axle, and keeps lubricant oil reliably.
In order to satisfy described needs, according to embodiments of the invention, a kind of bearing unit is provided, this bearing unit comprises axle, be configured to first radial bearing at circumferential upper support axle, axle axially on first radial bearing separating relation and arrange and to be configured at circumferential second radial bearing of upper support axle, and be configured to thrust-bearing at an end of thrust direction upper support axle, be arranged in the spacer element between first and second radial bearings, wherein be furnished with first and second radial bearings and thrust-bearing and except the shaft insertion hole that axle wherein is installed, have the housing of enclosed construction and be filled in viscous fluid in the housing.
According to another embodiment of the present invention, a kind of motor is provided, this motor comprises stator, rotor and is configured to support with respect to stator the bearing unit of the rotor that is used to rotate, and for this bearing unit, uses described first embodiment's bearing unit.
According to another embodiment of the present invention, a kind of electronic equipment is provided, and this electronic equipment comprises motor, and this motor comprises stator, rotor and is configured to support with respect to stator the bearing unit of the rotor that is used to rotate, and, use described first embodiment's bearing unit for this bearing unit.
Adopt this bearing unit, motor and electronic equipment, the rigidity of axle can raise so that reduce the deflection of axle, and can keep lubricant oil reliably.Therefore, can realize good greasy property and good rotating property.
In conjunction with the accompanying drawings, from following explanation and claims, can understand described and other purpose of the present invention, feature and advantage, similarly parts or element are represented by similar reference mark in the accompanying drawings.
Description of drawings
Fig. 1 is the perspective view that adopts messaging device of the present invention;
Fig. 2 is the sectional view along the line A-A intercepting of Fig. 1;
Fig. 3 is the perspective view that the heat radiating equipment that adopts motor of the present invention is used in expression;
Fig. 4 is the sectional view of the structure of expression motor shown in Figure 3;
Fig. 5 is the sectional view that bearing unit of the present invention is adopted in expression;
Fig. 6 is formed in the perspective view that dynamic pressure on the inner peripheral surface of radial bearing shown in Figure 5 produces groove;
Fig. 7 is the horizontal sectional view as the spacer element of the bearing unit parts of Fig. 5;
Fig. 8 is the horizontal sectional view of expression as another spacer element of the bearing unit parts of Fig. 5;
Fig. 9 is the horizontal sectional view of expression as the another spacer element of the bearing unit parts of Fig. 5;
Figure 10 is the oil seal sectional view partly of the bearing unit of Fig. 5;
Figure 11 is expression and the sectional view of the bearing unit of the bearing unit of Fig. 5 comparative example relatively;
Figure 12 is the variation of the bearing unit temperature of presentation graphs 5 volume-variation amount when raising and the sectional view of lubricant oil liquid level;
Figure 13 is the variation of the bearing unit temperature of presentation graphs 5 volume-variation amount when reducing and the sectional view of lubricant oil liquid level;
Figure 14 is the sectional view of maximum space volume of oil seal part of the bearing unit of presentation graphs 5; And
Figure 15 is the sectional view of expression prior art bearing unit.
Embodiment
Below, describe and adopt messaging device of the present invention.
With reference to figure 1, adopting messaging device of the present invention is the personal computer of notebook type.Computer 1 comprises display block 2 and the basic computer 3 that is used to show results such as information processing, and basic computer comprises the built-in information processing section of the arithmetical operation processing of carrying out multiple information.Keyboard 5 is arranged on the upper surface side of computer 3, so that import the operational order of computer 1 or therefrom import multiple information.Basic computer 3 has the heat radiating equipment 4 of the side of setting within it.Heat radiating equipment 4 have be used for radiation from the heat that for example is arranged in information processing loops such as CPU in the basic computer 3, disc type equipment and produces so that the cooling equipment of cooling computer main body 3 inboards.
The heat radiating equipment 4 that is built in the basic computer 3 is contained in the housing 6 that forms basic computer 3 shown in Figure 2.With reference to figure 3, heat radiating equipment 4 comprises the base 7 made by metallic material, drives the fan 8 that rotates, is contained in fan case and sink 11 in the fan 8 by motor 10.
Base 7 forms roughly L shaped shape as shown in Figure 3.Hot producing component 12 is connected on the surperficial 7a on of the base 7 that forms L shaped shape roughly is distolateral.Hot producing component 12 produces heat for example by central processing unit (CPU) (CPU) excitation the time.Hot producing component 12 transmits Sealing 12a via heat and is connected on the surperficial 7a of base 7.
Sink 11 is on another distolateral surperficial 7a that is fixed on base 7.Sink 11 is ripple type and fin type sink, and is made by the metallic material of the good for example aluminium of thermal radiation capability.Equally, base 7 and fan case 9 are preferably made by aluminium or iron, and these materials are the good metals of heat-radiating properties.
Be connected with hot producing component 12 and be connected with heat radiating equipment 4 and the base 7 of sink 11 on a plurality of mounting hole 7b are set, the heat that heat radiating equipment 4 and sink 11 radiation produce from hot producing component 12, and insert screw in the mounting hole, screw is used for base 7 is connected in the housing 6.Base 7 is connected on the projection 16 that is arranged on housing 6 inboards, as shown in Figure 2 by the set screw that is used for fixing that inserts mounting hole 7b in housing 6.
In the time of in base is connected housing 6, sink 11 is arranged on the position relative with being formed on through hole 17 in housing 6 sidewalls, shown in Fig. 2 and 3.
When motor drives rotation fan 8 on the direction shown in Fig. 3 arrow mark R1, the heat radiating equipment 4 of structure sucks air via the openings 14 that are formed in the housing 6 from device external in this way as mentioned above, and with air via suction port 13 suction fan casees 9.The air of the rotation suction fan case 9 by fan 8 flows on the direction shown in Fig. 2 and the 3 arrow mark D2, and further flows on the direction shown in another arrow mark D2 of Fig. 3, so that flow through sink 11.Then, air is discharged to the outside of housing 6 via through hole 17.
The heat that produces when by the way, the hot producing component on being connected to base 7 12 drives is delivered on the sink 11 that is connected on the base 7 via the base 7 that forms by the metallic material with good heat-radiating properties.At this moment, the fan 8 by the heat radiating equipment 4 that rotates by motor 10 from housing 6 outside inhaled airs along and between the fin of sink 11, flow, and the heat that will be delivered to sink 11 is radiated the outside of housing 6 via through hole 17.
With reference now to Fig. 4,, in heat radiating equipment, uses and adopt motor 10 of the present invention to comprise rotor 18 and stator 19.
Notice wherein holder 23 and the stator yoke 20 whole cylinder form that form with bearing unit 30 press fits.
The core body 22 that the coil that is applied with driving current is reeled on it is connected on the outer peripheral portion of the holder 23 that is integrally formed on the stator yoke 20, as shown in Figure 4.
Cooperating with stator 19 is connected on the rotatingshaft 31 with the rotor 18 that forms motor 10, and rotatingshaft rotates at bearing unit 30 upper supports, and it is rotated with rotatingshaft 31.Rotor 18 comprises rotor rim 24 and rotates and have the fan 8 of a plurality of blades 25 with rotor rim 24.By outer, molded on the outer circumferential face of rotor rim 24, the blade 25 of fan 8 forms whole with rotor rim 24.
The coil 21 of ring-shaped rotor magnet 26 and stator 19 is arranged on the inner peripheral surface of cylindrical part 24a of rotor rim 24 with forming relativenesses.Rotor magnet 26 is to have the plastic materials that replaces the magnetized S utmost point and the N utmost point on circumferentially, and by adhesive on the inner peripheral surface of rotor rim 24.
In the motor 10 with described this structure, driving current is fed on the coil 21 on stator 19 1 sides with predetermined excitation pattern from the drive circuit section that is arranged on motor 10 outsides.When driving current was supplied in this way, the effect between the magnetic field of magnetic field that rotor 18 produces by coil 21 and the rotor magnet 26 that comes from rotor 18 sides was rotated with rotatingshaft 31.When rotor 18 rotates, be connected on the rotor 18 and fan 8 with blade 25 also rotates with rotor 18.When fan 8 rotates, the air outside the equipment on the direction shown in the arrow mark D1 of Fig. 2 and 3 via being formed on that opening 14 housing 6 in sucks and mobile on the direction shown in the arrow mark D2.Then, air flows in sink 11, and is discharged to the outside of housing 6 via through hole 17, and air heat radiation that hot producing component 12 is produced is to the outside of basic computer 3, the inboard of cooling computer main body 3 thus thus.
With reference to Figure 4 and 5, the rotatingshaft 30 of shown motor 10 supports the bearing unit 30 that rotates thereon and comprises rotatingshaft 31, is furnished with at first radial bearing 32 of circumferential upper support rotatingshaft 31 and forms the relation of separating with first radial bearing 32 in the axial direction so that at second radial bearing 33 of circumferential upper support rotatingshaft 31.Bearing unit 30 also be included in the thrust-bearing 34 of thrust direction upper support rotatingshaft 31 1 ends and be arranged in first radial bearing 32 and second radial bearing 33 between spacer element 35 and as the lubricant oil 38 that is filled in the viscous fluid in the housing 37.Housing 37 side within it holds first radial bearing 32, spacer element 35, second radial bearing 33 and thrust-bearing 34, and has the enclosed construction except the axle mounting hole 45 that rotatingshaft 31 is installed.
The liquid level change that spacer element 35 forms the lubricant oil 38 that the volume that makes at lubricant oil 38 expands owing to temperature variation or fill in the housing 37 when shrinking remains in the scope of the axle mounting hole 45 that is formed with housing 37.
With reference to figure 5, rotatingshaft 31 comprises by first and second radial bearings 32 and 33 and is bearing in the shaft portion main body 31a at its outer circumferential face place and forms arc or conical in shape and the bearing support by thrust-bearing 34 supportings divide 31b on of shaft portion main body 31a is distolateral.Rotatingshaft 31 also comprises another the distolateral mounting portion 31c that goes up and have the rotary member of the rotor 18 that connects for example motor 10 on it that is arranged on shaft portion main body 31a.Rotatingshaft 31 comprises that also being arranged on bearing support divides groove 31d between 31b and the shaft portion main body 31a, breaks away from so that prevent rotatingshaft 31.Divide the 31b place, support rotatingshaft 31 at the outer circumferential face place of its shaft portion main body 31a and by housing 37 at the mounting portion 31c that is stretching out from axle mounting hole 45 at its bearing support by thrust-bearing 34 by first and second radial bearings 32 and 33.In addition, the pad 51 that breaks away from member as anti-axle is arranged on rotatingshaft 31 and the corresponding position of groove 31d.
First and second radial bearings 32 and 33 form cylinder form by sintered metal materials separately and arrange with relation spaced apart from each other in the axial direction.First and second radial bearings 32 and 33 are cooperated with the lubricant oil 38 of filling in the housing 37, so that form the dynamic pressure FDB, and first and second dynamic pressures produce groove 39 and 40 and are formed on rotatingshaft 31 and pass respectively on wherein first and second radial bearings 32 and 33 inner peripheral surface.
With reference to figure 6, each first and second dynamic pressure produces groove 39 and 40 and forms, and makes a pair of v-depression 39a or 40a appear at week in succession upwards on the internal surface of first radial bearing 32 or 33.Each first and second dynamic pressure produces groove 39 and 40 and forms, and makes this sense of rotation R 2 to the distolateral sensing rotatingshaft 31 of v-depression 39a or 40a.In addition, first and second dynamic pressures produce groove 39 and 40 first and second radial bearings 32 that form cylinder form and 33 axially on, form in pairs in parallel to each other at the place, upper and lower.Though notice that first and second dynamic pressures produce groove 39 and 40 and are separately positioned on first and second radial bearings 32 and 33, it is parallel to each other in pairs, the mode that dynamic pressure generation groove is set is not limited to this.For example, a pair of dynamic pressure produces groove and can be arranged in parallel to each other in the axial direction on first and second radial bearings 32 and 33 on the position, upper and lower, makes two pairs of dynamic pressures generation grooves altogether can be set.In other words, being arranged on dynamic pressure on first and second radial bearings 32 and 33 produces the quantity of groove and size and suitably selects according to the size of first radial bearing 32 and 33, length etc.To notice that first and second radial bearings 32 and 33 can be formed by brass, stainless steel or macromolecular material in addition.
In first and second radial bearings 32 and 33 that form the dynamic pressure FDB, around central axis C L when rotating continuously, the lubricant oil 38 of filling in the housing 37 are mobile in first and second dynamic pressures produce groove 39 and 40 on the direction shown in the arrow mark R2 of Fig. 6 for rotatingshaft 31 in being installed in first and second radial bearings 32 and 33.Thus, lubricant oil 38 produces dynamic pressure between the inner peripheral surface of the outer circumferential face of rotatingshaft 31 and first and second radial bearings 32 and 33, and the rotatingshaft 31 that rotates of supporting.The dynamic pressure of Chan Shenging is reduced to low-down degree with the friction factor between rotatingshaft 31 and first and second radial bearings 32 and 33 in the case, realizes the smooth rotation of rotatingshaft 31 thus.
Because first and second radial bearings 32 and 33 arrange that to be spaced from each other relation if the distance between first and second radial bearings 32 and 33 increases, the rigidity of rotatingshaft 31 can increase so in the axial direction.Therefore, the deflection of rotatingshaft 31 can be restrained, and rotating property can be increased.
Thrust-bearing 34 forms the bearing support pivot bearings of dividing 31b of supporting rotatingshaft 31, and this bearing forms arc or taper at a some place.
With reference to figure 5 and 7, spacer element 35 forms the substantial cylindrical shape and is arranged between first and second radial bearings 32 and 22.Spacer element 35 is formed with the outer diameter that can be contained in the housing 37, and its periphery contacts with housing 37.In addition, spacer element 35 is formed with slightly the inner diameter that the outer diameter greater than rotatingshaft 31 does not contact with rotatingshaft 31, promptly leaves predetermined gap between spacer element 35 and rotatingshaft 31.Predetermined gap between the outer circumferential face of spacer element 35 inner peripheral surfaces and rotatingshaft 31 is as communication path, so that in the zone that first radial bearing 32 is set be provided with to set up between another zone of second radial bearing 33 and be communicated with, as following description.In addition, a plurality of flow paths 49 that are used for lubricant oil 38 are formed on the part that spacer element 35 is positioned at housing 37 1 sides, promptly as shown in Figure 7 on the outer circumferential face of spacer element 35.Flow path 49 along the axial formation of rotatingshaft 31, and has along the cross section perpendicular to rotatingshaft 31 and to cut into roughly semicircular in shape on the outer circumferential face of spacer element 35, i.e. D shape cutting shape.Therefore, flow path 49 is used as between the zone that the regional of first radial bearing 32 is set therein and second radial bearing 33 wherein is set and sets up the communication path that is communicated with.Flow path 49 on the cross section perpendicular to rotatingshaft 31, be arranged on the outer circumferential face of spacer element 35 on six positions that equidistantly separate.
Predetermined gap between the inner peripheral surface of flow path 49 and spacer element 35 and the outer circumferential face of rotatingshaft 31 is cooperated, and makes first and second dynamic pressures of lubricant oil 38 fine inflow first and second radial bearings 32 and 22 produce groove 39 and 40.In other words, by make lubricant oil 38 on the suitable direction first and second dynamic pressures produce groove 39 and 40 and rotatingshaft 31 between produce and flow, floating of rotatingshaft 31 can be restrained in flow path 49 and described gap.
Particularly, spacer element 35 can reduce to be filled in the volume of the lubricant oil 38 in the bearing unit 30, as following description, and can keep lubricant oil 38 reliably by the cubical content that reduces lubricant oil 38 with respect to temperature variation.
Notice that the spacer element that forms bearing unit 30 is not limited to the spacer element 35 that forms in this way.Particularly, any element can be used as spacer element, as long as it is arranged between first and second radial bearings 32 and 33, and the volume that reduces the lubricant oil 38 of filling in the bearing unit 30 gets final product.
For example, the spacer element that forms bearing unit 30 can be the spacer element that forms cylinder form, and this spacer element has roughly hexagonal cross-section as shown in Figure 8.Be similar to spacer element 35, having roughly, the spacer element 35a of hexagonal cross-section is arranged between first and second radial bearings 32 and 33.Spacer element 35a has the outer circumferential face that forms certain size, and by this size, it can be contained in the housing 37, and has slightly the inner diameter greater than the outer diameter of rotatingshaft 31, does not contact with rotatingshaft 31 simultaneously.In other words, spacer element 35a forms the predetermined gap that leaves rotatingshaft 31.Spacer element 35a cooperates with the inner peripheral surface of housing 37, so that be formed for a plurality of flow path 49a of lubricant oil 38.Flow path 49a is used as between the zone that the regional of first radial bearing 32 is set therein and second radial bearing 33 wherein is set and sets up the communication path that is communicated with.
In addition, the spacer element of formation bearing unit 30 can be circular shape shown in Figure 9 and the spacer element 35b with formation a plurality of through holes in the axial direction.Be similar to spacer element 35, the spacer element 35b with formation through hole wherein is arranged between first and second radial bearings 32 and 33.Spacer element 35b has outer diameter, and this outer diameter has makes it can be contained in the housing 37 and the size that contacts with housing 37, and spacer element has the inner diameter that does not contact rotatingshaft 31 slightly greater than the outer diameter of rotatingshaft 31 simultaneously.In other words, spacer element 35b forms the predetermined gap that leaves rotatingshaft 31.Be formed on the communication path 49b that the through hole in the spacer element 35b flows therein as lubricant oil 38.Flow path 49b forms through hole, and this through hole extends in the axial direction, and on the cross section perpendicular to rotatingshaft 31, relation roughly forms on the circle sentencing mutually equidistantly on the thickness direction of spacer element 35b, in the precalculated position.Flow path 49b is used as between the zone that the regional of first radial bearing 32 is set therein and second radial bearing 33 wherein is set and sets up the communication path that is communicated with.
Be formed on each communication path 49a in spacer element 35a and the 35b and 49b respectively with the inner peripheral surface of spacer element 35a and 35b between predetermined gap and the outer circumferential face of rotatingshaft 31 cooperate, make lubricant oil 38 be recycled in first and second dynamic pressures generation groove 39 or 40 of first radial bearing 32 or second radial bearing 33.In other words, by make lubricant oil 38 first and second dynamic pressures produce groove 39 and 40 and rotatingshaft 31 between, on suitable direction, form and flow, floating of rotatingshaft 31 can be restrained in flow path 49a and 49b and described gap.
Refer back to Fig. 5, housing 37 comprises housing body 42, bottom closure portion 43 and top closing section 44.Housing 37 has and holds and around each self-forming cylinder form and in the axial direction to separate first and second radial bearings 32 that relation arranges and 33 shape.Housing body 42 is arranged on the outside of first and second radial bearings 32 and 33.Lower openings on one side of bottom closure portion 43 closure shell main bodys 42.Closing section 44 closures in top are formed on the upper opening on the lower openings opposite side with housing body 42.Housing body 42 has tubular form, and is formed by metallic material.In addition, top closing section 44 and bottom closure portion 43 are formed by the metallic material that is similar to housing body 42.
Thrust-bearing 34 is arranged in the central part office on the inner surface side of bottom closure portion 43.Bearing support divides 31b being arranged on the end on the thrust direction that is bearing in the rotatingshaft 31 on first and second radial bearings 32 and 33, and rotates by thrust-bearing 34 supportings.
Formed by metallic material though notice housing body 42, top closing section 44 and base section 43, they also can be formed and is formed integral body mutually by welding by the synthetic resin material.Have in use under the situation of synthetic resin as the material that is used for housing 37 of good greasy property, can realize big relatively contact angle.Therefore, under centrifugal force leak, can reduce the length dimension of a mounting hole 45 owing to restrained lubricant oil.
By the way, the axle mounting hole 45 of housing 37 is formed with slightly the inner diameter greater than the outer diameter of the mounting portion 31e of rotatingshaft 31, this mounting portion is mounted in the part in the mounting hole 45, makes mounting portion 31e to rotate, and not with the inner peripheral surface sliding contact of axle mounting hole 45.At this moment, axle mounting hole 45 forms, between the outer circumferential face of the mounting portion 31e that makes at the inner peripheral surface of axle mounting hole 45 and rotatingshaft 31 gap 47 is set, this gap has distance c, and this distance is enough to prevent to be filled in lubricant oil 38 in the housing 37 from housing 37 inner side leakage.Top closing section 44 forms the oil seal section in this way, forms axle mounting hole 45 in the closing section of top, makes to prevent that the gap 47 that the housing 37 interior lubricant oil of filling 38 leak is formed between a mounting hole 45 and the rotatingshaft 31.
In addition, tapering part 48 is arranged on the outer circumferential face of the rotatingshaft 31 relative with the inner peripheral surface of axle mounting hole 45.Tapering part 48 tilts, and makes that the gap 47 between the inner peripheral surface of the outer circumferential face be formed on rotatingshaft 31 and axle mounting hole 45 increases towards the outside of housing 37.Tapering part 48 forms pressure gradient in the gap 47 that the inner peripheral surface by the outer circumferential face of rotatingshaft 31 and axle mounting hole 45 forms, can produce to be filled in the power that housing 37 interior lubricant oil 38 are drawn into housing 37 inboards.Because when housing 37 rotates, lubricant oil 38 is tending towards being drawn into the inboard of housing 37, first and second dynamic pressures that lubricant oil 38 enters first and second radial bearings 32 that form the dynamic pressure FDB and 33 reliably produce groove 39 and 40, and produce dynamic pressure.Therefore, rotatingshaft 31 carries out stable support, and the lubricant oil 38 that can prevent to be filled in the housing 37 leaks.
In order to make the bearing unit 30 of structure in this way, at first first radial bearing 32 is connected on the housing body 42, after this connects second radial bearing 33.Then, pad 51 and thrust-bearing 33 are connected on the bottom closure portion 43, and follow described housing body 42 and be connected on the bottom closure portion 43, after this connect top closing section 44.Then, on the another location between the position between housing body 42 and the top closing section 44 and housing body 42 and the bottom closure portion 43, hermetic unit 46 forms so that combine with housing 37 by laser bonding.Then, rotatingshaft 31 inserts in this way and forms in the whole housing 37.
In bearing unit 30, tapering part 48 is set, tapering part tilt to make the gap 47 between the inner peripheral surface of the outer circumferential face that is formed on rotatingshaft 31 and axle mounting hole 45 increase towards housing 37 outsides.Therefore, in the distance c in the gap 47 that the inner peripheral surface by the outer circumferential face of rotatingshaft 31 and axle mounting hole 45 forms, form pressure gradient, and produce and be tending towards to be filled in the power that housing 37 interior lubricant oil 38 are drawn into housing 37 inboards.In other words, in bearing unit 30, the gap 47 that is formed between the inner peripheral surface of the outer circumferential face of rotatingshaft 31 and axle mounting hole 45 prevents lubricant oil 38 because surface tension seals and to disperse.
In bearing unit 30 with described structure, because it has the structure that first and second radial bearings 32 and 33 are arranged in the axial direction with being spaced from each other, by between first and second radial bearings 32 and 33, guaranteeing big distance, the rigidity of rotatingshaft 31 can raise, and reduces the deflection of rotatingshaft 31 thus.In other words, adopt bearing unit 30 of the present invention rigidity can be higher than and have, and realize the lifting of rotating property in the past because radial bearing forms the rigidity that concerns the limit that causes.
In addition, in adopting bearing unit 30 of the present invention, spacer element 35 is arranged between first and second radial bearings 32 and 33.Therefore, increase the overall volume of lubricant oil 38 by the amount of space between first and second radial bearings 32 and 33, this has adverse effect to separate in the axial direction at first and second radial bearings 32 and 33 when relation is arranged.Therefore, can prevent because the problem of the liquid level change that temperature variation and similar problem cause.
Here, describe in detail by the problem that spacer element 35 prevents temperature variation is set.In order to compare, be described for the bearing unit 60 of the comparative example that does not comprise spacer element with adopting described bearing unit 30 of the present invention.Notice in the description of the bearing unit 60 of comparative example, indicate similar reference mark, and omit it here and be repeated in this description to avoid burdensome with described bearing unit 30 similar parts.
With reference to Figure 11, bearing unit 60 comprises rotatingshaft 31, be used at first radial bearing 32 of circumferential upper support rotatingshaft 31 and form with first radial bearing 32 that the relation of separating is arranged in the axial direction so that at circumferential second radial bearing 33 of upper support rotatingshaft 31.Bearing unit 60 also comprises the housing 37 that is used at the thrust-bearing 34 of thrust direction upper support rotatingshaft 31 1 ends, wherein holding first radial bearing 32, second radial bearing 33 and thrust-bearing 34, and as the lubricant oil 68 that is filled in the viscous fluid in the housing 37.
So, be shown oil seal section volume V b at the lubricant oil 38 of oil seal section or 68 strapping table, and be filled in lubricant oil 38 in the housing 37 outside this oil seal section or 68 strapping table and be shown sealed lower portion volume V a, being filled in the lubricant oil 38 in bearing unit 30 or 60 or the overall volume of lubricant oil 68 is summations of oil seal section Vb and sealed lower portion volume V a, as following representation (1) expression:
V＝Va+Vb...(1)
Here, in temperature variation Δ T ℃ the time, lubricant oil 38 or 68 volume change the volume-variation amount Δ V by expression (2) expression:
ΔV＝(1+αΔT).V-V
＝αΔT.V...(2)
Wherein α is the coefficient of volumetric expansion of lubricant oil.Notice that Figure 12 represents the relation between the liquid level of volume-variation amount Δ V and lubricant oil 38 or 68.In Figure 12, reference symbol SN represents the liquid level of lubricant oil under the room temperature, and the liquid level of SH lubricant oil when representing T ℃ of temperature rising Δ.Relation when simultaneously, Figure 13 is illustrated in temperature and reduces T ℃ of Δ between the liquid level of volume-variation amount Δ V and lubricant oil 38 or 68.In Figure 13, reference symbol SN represents the liquid level of lubricant oil under the room temperature, and the liquid level of SL lubricant oil when representing that temperature reduces T ℃ of Δ.
So, under the situation that the maximum space volume of oil seal section is represented by Vc, maximum space volume V c need be set so that satisfy following representation (3):
Vc-Vb＞ΔV...(3)
Reason is if do not satisfy representation (3), and so when temperature is high, promptly when T ℃ of temperature rising Δ, lubricant oil 38 or 68 leaks from sealing section (being bearing unit 30 or 60).
On the other hand, oil seal section volume V b need be set, so that satisfy following representation
(4)：
Vb＞ΔV...(4)
Reason is if do not satisfy representation (4), and so when temperature is low, promptly when temperature reduced T ℃ of Δ, lubricant oil 38 or 68 was discharged from lubricant oil 38 or 68, and air is sneaked into the bearing unit inboard from the outside.
So that when temperature variation, obtain the suitable liquid level of lubricant oil 38 or 68, need make that the maximum space volume V c of oil seal section is big and/or make that volume-variation amount Δ V is little in order to satisfy described representation (3) and (4).
In order to make maximum space volume V c big, need the distance of spreading axis mounting hole 45 and rotatingshaft 31, and/or the height t height of feasible axle mounting hole 45.But, if expand this distance, applying when impacting, the problem that lubricant oil disperses easily appears so, and if the height t of axle mounting hole 45 make when very high, the length that occurs the short transverse of whole bearing unit so becomes big problem.
By adopting bearing unit 30 of the present invention, the total measurement (volume) V of lubricant oil reduces to equal the amount of the volume of spacer element 35 under the room temperature, rather than the volume of the bearing unit 60 of described comparative example.Therefore, can reduce volume-variation amount Δ V, and can eliminate described this problem.
Particularly, adopt bearing unit 30 of the present invention to comprise the spacer element 35 that is formed with certain size, this size can absorb because the expansion and the contraction of the lubricant oil 38 that temperature variation causes.Therefore, when the temperature variation of lubricant oil 38, the liquid level change of lubricant oil 38 can be limited in a mounting hole 45 formed scopes.Therefore, can prevent air mixing in lubricant oil 38 and lubricant oil 38 leak into hull outside.
In other words, owing to adopt bearing unit 30 of the present invention to comprise the spacer element 35 that is arranged between first and second radial bearings 32 and 33, can reduce because the volume-variation amount Δ V of the lubricant oil 38 that temperature variation causes.Therefore, lubricant oil 38 leaks into the outside of bearing unit 30 in the time of can preventing that temperature from raising, and can prevent that temperature from reducing the time owing to come from the liquid level of the lubricant oil 38 of oil seal section and reduce and cause air mixing to arrive in the lubricant oil 38.Therefore, can prevent because the reduction of rotating property, greasy property and similar performance that oil leak and air mixing cause in the lubricant oil.In other words, adopt bearing unit 30 of the present invention to make lubricant oil 38 to remain on reliably in this unit.
In addition, by adopting bearing unit 30 of the present invention, owing to can reduce the volume-variation amount Δ V of the lubricant oil 38 that temperature variation causes, can be with size (i.e. the height of the axle mounting hole 45) supression in the axial direction of oil seal section in minimum value.Therefore, bearing unit size in the axial direction can be restrained in small size, and can realize the miniaturization of this equipment.
Therefore,,, can reduce the deflection of rotatingshaft 31 and keep lubricant oil 38 reliably, obtain good greasy property and good rotating property thus because rotatingshaft 31 forms the rigidity that increases by adopting bearing unit 30 of the present invention.
In addition, by adopting bearing unit 30 of the present invention, be formed in the spacer element 35 that is arranged between first and second radial bearings 32 and 33 owing to be used for the flow path 49 of lubricant oil 38, oil is easily in dynamic pressure FDB circulates inside.Therefore, first and second dynamic pressures of first and second radial bearings 32 and 22 produce groove 39 and 40 and rotatingshaft 31 between form lubricant oil 38 flowing on suitable direction, and therefore can restrain floating of rotatingshaft 31.Therefore, adopt bearing unit 30 of the present invention can prevent that following situation from occurring, promptly because rotatingshaft 31 floats, and the liquid level of lubricant oil 38 reduces, and air mixing is in lubricant oil 38.
In this way, adopt bearing unit 30 of the present invention can realize good greasy property and good rotating property, this has increased the versatility and the selectivity of bearing unit, and improves the degrees of freedom of the product structure that uses bearing unit.
In addition, owing to adopt motor of the present invention and electronic equipment to comprise described bearing unit 30, they can realize good rotating property for a long time, and reduce the situations such as deflection of rotatingshaft 31, and good greasy property.
The bearing that adopts bearing unit of the present invention to be not limited to be used for heat radiating equipment and the spindle motor of disk drive also go for the bearing of multiple motor.
In addition, adopt bearing unit of the present invention to be extensive use of, and be not limited to motor, and can be used for comprising the various mechanism of rotatingshaft and other mechanism of supporting the parts that rotate with respect to axle.
It should be understood by one skilled in the art that according to structural requirement and other factors and can carry out multiple modification, remodeling, combination and variation, as long as they are in the scope of claims or its equivalents.
Claims (5)
1. bearing unit comprises:
Axle;
Be configured to first radial bearing at the described axle of circumferential upper support;
Described axle axially on described first radial bearing to separate relation and arrange and to be configured at circumferential second radial bearing of the described axle of upper support;
Be configured to thrust-bearing at an end of the described axle of thrust direction upper support;
Be arranged in the spacer element between described first and second radial bearings;
Wherein be furnished with the housing of described first and second radial bearings and described thrust bearing, housing has the enclosed construction except the shaft insertion hole that described axle wherein is installed; And
Be filled in the viscous fluid in the described housing.
2. bearing unit as claimed in claim 1; It is characterized in that,
Described spacer element forms, and makes described viscous fluid in being filled in described housing expand owing to temperature variation or when shrinking, the liquid level change of described viscous fluid remains in the formed scope of described shaft insertion hole of described housing.
3. bearing unit as claimed in claim 1 is characterized in that,
Described spacer element has the formation flow path that is used for described viscous flow wherein.
4. motor comprises:
Stator;
Rotor; And
Be configured to support described rotor so that the bearing unit that rotates with respect to described stator;
Described bearing unit comprises:
Axle;
Be configured to first radial bearing at the described axle of circumferential upper support;
Described axle axially on described first radial bearing to separate relation and arrange and to be configured at circumferential second radial bearing of the described axle of upper support;
Be configured to thrust-bearing at an end of the described axle of thrust direction upper support;
Be arranged in the spacer element between described first and second radial bearings;
Wherein be furnished with the housing of described first and second radial bearings and described thrust bearing, housing has the enclosed construction except the shaft insertion hole that described axle wherein is installed; And
Be filled in the viscous fluid in the described housing.
5. electronic equipment comprises:
Motor, motor comprises stator;
Rotor; And
Be configured to support described rotor so that the bearing unit that rotates with respect to described stator;
Described bearing unit comprises:
Axle;
Be configured to first radial bearing at the described axle of circumferential upper support;
Described axle axially on described first radial bearing to separate relation and arrange and to be configured at circumferential second radial bearing of the described axle of upper support;
Be configured to thrust-bearing at an end of the described axle of thrust direction upper support;
Be arranged in the spacer element between described first and second radial bearings;
Wherein be furnished with the housing of described first and second radial bearings and described thrust bearing, housing has the enclosed construction except the shaft insertion hole that described axle wherein is installed; And
Be filled in the viscous fluid in the described housing.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005-185601 | 2005-06-24 | ||
| JP2005185601 | 2005-06-24 | ||
| JP2005185601A JP2007002949A (en) | 2005-06-24 | 2005-06-24 | Bearing unit, motor with bearing unit, and electronic device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1884863A CN1884863A (en) | 2006-12-27 |
| CN100434737C true CN100434737C (en) | 2008-11-19 |
Family
ID=37567603
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100908197A Expired - Fee Related CN100434737C (en) | 2005-06-24 | 2006-06-26 | Bearing unit and motor and electric apparatus having bearing unit |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US20060292015A1 (en) |
| JP (1) | JP2007002949A (en) |
| CN (1) | CN100434737C (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI339242B (en) * | 2007-11-02 | 2011-03-21 | Delta Electronics Inc | Fan, motor and oil sealing structure |
| TW202043618A (en) * | 2016-03-18 | 2020-12-01 | 日商威爾柯股份有限公司 | Tube pump, rotation restricting member, shaft and shaft coupling structure |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6361214B1 (en) * | 1999-08-02 | 2002-03-26 | Nidec Corporation | Hydrodynamic-pressure bearing device and motor provided with the hydrodynamic-pressure bearing device |
| CN1097178C (en) * | 1998-07-17 | 2002-12-25 | 皇家菲利浦电子有限公司 | Dynamic groove bearing comprising porous lubricant reservoir |
| JP2003130043A (en) * | 2001-10-24 | 2003-05-08 | Sony Corp | Bearing unit and motor provided therewith |
| CN1616839A (en) * | 2003-11-14 | 2005-05-18 | 索尼株式会社 | Bearing unit, and motor and electronic device with said bearing unit |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2864941B2 (en) * | 1993-04-27 | 1999-03-08 | 株式会社日立製作所 | Rotating body bearing device, motor and polygon mirror motor |
| GB2306583A (en) * | 1995-10-28 | 1997-05-07 | Daewoo Electronics Co Ltd | Lubricated journal bearing assembly |
| JP3200556B2 (en) * | 1996-01-30 | 2001-08-20 | 株式会社日立製作所 | Magnetic fluid bearing unit and motor equipped with the same |
| US6172847B1 (en) * | 1997-03-27 | 2001-01-09 | Nsk Ltd. | Rotational assembly for disc drive device having small runout and reduced axial displacement |
| NL1010020C2 (en) * | 1997-09-08 | 1999-06-23 | Ntn Toyo Bearing Co Ltd | Spindle motor and device for supporting the rotating shaft of a spindle motor. |
| KR100968163B1 (en) * | 2002-04-23 | 2010-07-06 | 엔티엔 가부시키가이샤 | Fluid bearing device |
| DE202005000155U1 (en) * | 2005-01-07 | 2006-05-18 | Minebea Co., Ltd., Kitasaku | Fluid dynamic storage system |
-
2005
- 2005-06-24 JP JP2005185601A patent/JP2007002949A/en not_active Abandoned
-
2006
- 2006-06-12 US US11/450,340 patent/US20060292015A1/en not_active Abandoned
- 2006-06-26 CN CNB2006100908197A patent/CN100434737C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1097178C (en) * | 1998-07-17 | 2002-12-25 | 皇家菲利浦电子有限公司 | Dynamic groove bearing comprising porous lubricant reservoir |
| US6361214B1 (en) * | 1999-08-02 | 2002-03-26 | Nidec Corporation | Hydrodynamic-pressure bearing device and motor provided with the hydrodynamic-pressure bearing device |
| JP2003130043A (en) * | 2001-10-24 | 2003-05-08 | Sony Corp | Bearing unit and motor provided therewith |
| CN1616839A (en) * | 2003-11-14 | 2005-05-18 | 索尼株式会社 | Bearing unit, and motor and electronic device with said bearing unit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1884863A (en) | 2006-12-27 |
| JP2007002949A (en) | 2007-01-11 |
| US20060292015A1 (en) | 2006-12-28 |
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Granted publication date: 20081119 |