Background technique
Drive in the rotary type motor that uses in using with, FDD with, ODD etc. in polygonal mirror 5 revolution, turning axle is bearing on the oil dynamic bearing means 10 shown in Fig. 5 (A), (B) pivotally.In general, oil dynamic bearing means 10 comprises: have the radial bearing 11 that outer circumferential face with respect to turning axle 3 is separated with radial bearing gap 111 and is the radial bearing surface 110 of subtend, the thrust-bearing 12 of the lower end surface 38 of supporting rotating shaft 3, and the lubricant oil of filling in radial bearing gap 111; Outer circumferential face or radial bearing surface 110 at turning axle 3 are formed with the dynamic pressure occurrence groove.
Wherein, sphere is processed in the lower end surface 38 of turning axle 3, is used for the slip that contacts with thrust bearing surface 120.When sphere was processed in the lower end surface 38 of turning axle 3, in the underpart 34 of turning axle 3, the boundary part of sphere and pole part was formed with edge 30, when the part suitable with this edge 30 is positioned at the inside of radial bearing 11, can damage radial bearing surface 110.For this reason, the underpart 34 of turning axle 3 is processed into from the lower end surface 114 of radial bearing 11 stretches out, so that the part suitable with the edge 30 of turning axle 3 is positioned at the outside of radial bearing 11 with institute's sizing.
Yet,, produced big space E around the underpart 34 of turning axle 3 if stretch out from the lower end surface 114 of radial bearing 11 underpart 34 of turning axle 3.Though also be filled with lubricant oil in this space E, after space E increased, the air that lodges in this place became obstacle, and lubricant oil filling fully exists to form the still residual problem that air condition is arranged easily.
In this state, in case ambient temperature changes, the problem that can not obtain original projected life is discharged, caused to then air expansion or contraction so exist lubricant oil from radial bearing gap 111.
Again, in case air accumulation around the underpart 34 of turning axle 3, air may enter the inside of radial bearing 11 when then turning axle 3 turned round, under this state, bearing loss torque and bearing rigidity change, rock and the axle swing changes, and the result makes the motor characteristic instability.
Particularly be formed with the man type chute and axially in the concavo-convex oil dynamic bearing means of taper, because of the pressure that utilizes lubricant oil obtains motor characteristic, so generation the problems referred to above easily in the outer circumferential face of turning axle 3 or radial bearing surface 110.And, axially be formed with groove, circumferentially be in the dynamic pressure groove of taper, because of lubricant oil moves easily vertically, so this problem is more prone to come to the surface.
Again, in oil dynamic bearing means 10, be lubricated the supply of oil in order to ensure its life-span, even but carry out this supply, if exist large space around the underpart 34 of turning axle 3, then the lubricant oil major part of supply is lodged in this place, can not be to radially bearing play 111 supplies, and the result is the life-span that can not guarantee original design.
In view of above problem, the objective of the invention is to, provide and fully to guarantee lubricant oil in a kind of radial bearing gap and can prevent that air from invading, can improve the oil dynamic bearing means of motor characteristic and reliability thus and using the motor of this device to bearing play radially.
Summary of the invention
For achieving the above object, the invention is characterized in, be provided with the adjustment part, gap of the ring-type of subtend, the adjustment part, gap of the ring-type of this subtend is separated with the 1st gap and is subtend with respect to the outer circumferential face of revolution shaft lower end portion, simultaneously and the lower end surface of radial bearing between form the 2nd gap, and the size in the described radial bearing gap of adjustment part, described gap, described the 1st gap, described the 2nd gap is during respectively as A, B, C, and A, B, C should satisfy A<B<C.
The present invention is spherical oil dynamic bearing means applicable to the lower end surface of described turning axle or the lower end surface of this turning axle, and the part of the spherical lower end surface of this turning axle of supporting of described thrust-bearing is the oil dynamic bearing means of sphere but the lower end surface that also can effectively the present invention be applicable to described turning axle is sphere.
In the present invention, be provided with the annular gap adjustment part with the lower end surface subtend of the outer circumferential face of revolution shaft lower end portion and radial bearing, utilize this adjustment part, gap, only the outer circumferential side in revolution shaft lower end portion has formed the 1st gap, and the space is little.Like this, even stretch out from the lower end surface of radial bearing the underpart of turning axle, there is not big space around the underpart of turning axle, so under the state after the lubricant oil filling, the outer circumferential side of revolution shaft lower end portion (the 1st gap) is air accumulation not yet.Thus, outer circumferential face or radial bearing surface at turning axle are formed with man type chute and the concavo-convex occasion of taper, even the environment variation of temperature takes place, the air of the outer circumferential side of revolution shaft lower end portion can not expand or shrink yet, so lubricant oil can not discharged from the radial bearing gap.Again, because of air does not enter the inside (radial bearing gap) of radial bearing, so motor characteristic is stable.Again, though in supply after the lubricant oil, do not have big space around the underpart because of turning axle, so the major part of the lubricant oil of supply can not accumulate in this part.And, the outer circumferential side of radial bearing is communicated with the radial bearing gap by the 2nd gap and the 1st gap, but because the size in these gaps has above-mentioned magnitude relationship, therefore the lubricant oil that lodges in the radial bearing outer circumferential side utilizes wicking to be introduced into the 1st gap through the 2nd gap, and the lubricant oil that is introduced into the 1st gap utilizes wicking to be introduced into the radial bearing gap.Like this, so the state after the lubricant oil in the radial bearing gap is in filling always is the reliability height.
Among the present invention, when forming described the 2nd gap, can form the degree of depth in the upper-end surface of adjustment part, described gap be the groove of size C.Adopt this structure, even the upper-end surface of radial bearing is formed with the groove that constitutes oily path, the lower end surface of radial bearing itself does not need to form the groove of oily path yet.Like this, during assembling oil dynamic bearing means, because of can be according to there being the slotless diameter to make differentiation up and down, so can avoid with reverse configuration about the radial bearing to bearing.
Among the present invention, when forming described the 2nd gap, can also form the groove that the degree of depth is size C in the lower end surface of described radial bearing.
Among the present invention, described radial bearing preferably is installed in the bearing mounting hole of the bearing support that is disposed at its outer circumferential side, the 3rd gap of formation dimension D between the inner peripheral surface of the outer circumferential face of described radial bearing and described bearing mounting hole simultaneously, and the dimension D in the 3rd gap should satisfy C≤D.Adopt this structure, the lubricant oil that accumulates in the 3rd gap that is formed between radial bearing and bearing support utilizes wicking successfully to be introduced into the 2nd gap, so lubricant oil is supplied with the geocentric vertical bearing play smoothly via the 2nd gap and the 1st gap.
Among the present invention, adjustment part, described gap preferably is made of the cushion member of shape around the underpart that is configured to surround described turning axle.Adopt this structure,, can improve motor characteristic and reliability as long as in original structure, add cushion member.
Among the present invention, if effective especially when the dynamic pressure occurrence groove that radial bearing surface forms axially is formed with its concavo-convex axial hydrodynamic occurrence groove.In this occasion, though lubricant oil when revolution side shifting outside axially easily, because of having said structure, so the smooth geocentric vertical of lubricant oil bearing play can be supplied with.
Described oil dynamic bearing means is particularly useful for a rotary type motor.
In sum, in the present invention, the lower end surface subtend with the outer circumferential face and the radial bearing of revolution shaft lower end portion is arranged in the annular gap adjustment part, utilizes this adjustment part, gap, and only the outer circumferential side in revolution shaft lower end portion forms the 1st gap, and the space is little.Like this, even stretch out from the lower end surface of radial bearing the underpart of turning axle, there is not big space around the underpart of turning axle, so under the state after the lubricant oil filling, the outer circumferential side of revolution shaft lower end portion (the 1st gap) is air accumulation not yet.Thus, outer circumferential face or radial bearing surface at turning axle are formed with man type chute and the concavo-convex occasion of taper, even the environment variation of temperature takes place, the air of the outer circumferential side of revolution shaft lower end portion can not expand or shrink yet, so lubricant oil can not discharged from the radial bearing gap.Again, because of air does not enter the inside (radial bearing gap) of radial bearing, so motor characteristic is stable.Again, though in supply after the lubricant oil, do not have big space around the underpart because of turning axle, so the major part of the lubricant oil of supply can not accumulate in this part.And, the outer circumferential side of radial bearing is communicated with the radial bearing gap by the 2nd gap and the 1st gap, but because the size in these gaps has above-mentioned magnitude relationship, therefore the lubricant oil that lodges in the radial bearing outer circumferential side utilizes wicking to be introduced into the 1st gap through the 2nd gap, and the lubricant oil that is introduced into the 1st gap utilizes wicking to be introduced into the radial bearing gap.Like this, so the state after the lubricant oil in the radial bearing gap is in filling always is the reliability height.
Embodiment
The axle rotary type motor 1 that is suitable for oil dynamic bearing means of the present invention and uses this device is described with reference to the accompanying drawings.In addition, the basic structure of oil dynamic bearing means of the present invention is identical with the structure that has illustrated with reference to Fig. 5, so describe at general part mark prosign.
[embodiment 1]
Fig. 1 is the sectional view of oil dynamic bearing means of the present invention and the axle rotary type motor that uses this device thereof.
Fig. 2 (A), (B), (C) are respectively the oil dynamic bearing means sectional view of the embodiment of the invention 1, the amplification half sectional view of the end portion periphery of turning axle and the stereogram of use therein liner.
Among Fig. 1, the axle rotary type motor 1 of present embodiment comprises: motor framework 2; Be equipped on the oil dynamic bearing means 10 on this motor framework 2; Be supported on the turning axle 3 on this oil dynamic bearing means 10 pivotally; And the rotor hub 4 that is installed on turning axle 3 upper end parts.The stepped part mounting that forms at rotor hub 4 outer circumferential sides has polygonal mirror 5, uses the stage clip 6 that is fixed in turning axle 3 upper end portions by screw etc. with these polygonal mirror 5 pushings and be fixed on the rotor hub 4.
Side is fixed with to outer circumferential side expansion and from the crooked downwards yoke 41 of outer circumferential side below rotor hub 4, is fixed with rotor magnet 42 in the inboard of the cylindric side face of yoke 41.Corresponding with it, on framework 2, fixing laminate core 8 by retainer 80 unshakable in one's determination.On this laminate core 8, salient pole peripheral end face and rotor magnet 42 subtends partly to outer circumferential side stretches out partly are wound with coil 9 at salient pole simultaneously.
Shown in Fig. 1 and Fig. 2 (A), (B), (C), the oil dynamic bearing means 10 that uses in the axle rotary type motor 1 of this structure comprises: have the radial bearing 11 that outer circumferential face with respect to turning axle 3 is separated with radial bearing gap 111 and is the radial bearing surface 110 of subtend; And the thrust-bearing 12 of thrust bearing surface 120 with lower end surface 38 of supporting rotating shaft 3.Wherein, on the outer circumferential face of turning axle 3 or radial bearing surface 110, be formed with dynamic pressure occurrence groove or the lambdoid dynamic pressure occurrence groove that constitutes by the taper groove that extends along axial direction.The above-mentioned taper groove that extends along axial direction is exactly known dynamic pressure occurrence groove, is that a kind of axial direction concavo-convex is formed up to axial end and it is concavo-convex for circumferentially being taper always.
Again, oil dynamic bearing means 10 has the bearing support 15 that is fixed in motor framework 2, and radial bearing 11 is pressed in the bearing mounting hole 150 that is fixed on this bearing support 15.Wherein, equally spaced be formed with a plurality of protuberances 159 of the outer circumferential face 117 that stretches out to the inside from the inner peripheral surface of bearing mounting hole 150, can bear radial bearing 11 on bearing support 15, the outer circumferential face 117 of radial bearing 11 is in the state that axial direction is formed with gap (the 3rd gap 155) with the inner peripheral surface of the bearing mounting hole 150 of bearing support 15.In addition, in bearing support 15, packing ring 18 is installed in the top position of radial bearing 11.
On the other hand, below bearing support 15, in the side recess, fixing thrust-bearing 12 by Bearing Installation plate 17.
In the oil dynamic bearing means 10 of this structure, sphere is processed in the lower end surface 38 of turning axle 3, is used for contacting slip with thrust bearing surface 120.Like this, in case sphere is processed in the lower end surface 38 of turning axle 3, then when turning axle 3 is inserted radial bearing 11, also has the advantage of the inner peripheral surface (radial bearing surface 110) that does not damage radial bearing 11.
At this, in case sphere is processed in the lower end surface 38 of turning axle 3, then be formed with edge 30,, then can damage radial bearing surface 110 if be positioned at the inside of radial bearing 11 with the considerable part at this edge 30 at the sphere of the underpart 34 of turning axle 3 and the boundary part of pole part.In order to make the outside that is positioned at radial bearing 11 with the considerable part at the edge 30 of turning axle 3, stretch out with institute's sizing from the lower end surface 114 of radial bearing 11 underpart 34 of turning axle 3.
Under this state, though around the underpart 34 of turning axle 3, produced large space, but present embodiment is fixed with the ring-type liner 19 (adjustment part, gap) of subtend in the configuration of the inboard of bearing support 15, this liner 19 both was separated with the 1st gap 35 and was subtend with respect to underpart 34 outer circumferential faces of turning axle 3, again and be formed with the 2nd gap 115 between the lower end surface 114 of radial bearing 11.
Wherein, the lower end surface 114 of radial bearing 11 is flat condition, and the upper-end surface 195 of liner 19 is formed with the groove 199 that the degree of depth is size C, utilizes this groove 199 to form the 2nd gap 115.In addition, be formed with the oil circulation groove 118 of lubricant oil by usefulness in the upper-end surface of radial bearing 11, all sides are communicated with outer circumferential side in making.
In the oil dynamic bearing means 10 of this structure, liner 19 be designed to following form promptly, when the size in the 115, the 3rd gap 155, the 35, the 2nd gap, the 111, the 1st gap, radial bearing gap is respectively A, B, C, D, the relation of the A in the present embodiment, B, C, D should satisfy A<B<C≤D.
When this axle rotary type motor 1 with oil dynamic bearing means 10 of assembling, rotor hub 4 is fixed in turning axle 3 forms rotor assembly, again laminate core 8 and oil dynamic bearing means 10 are equipped on the framework 2 and form stator module, filling lubricant oil when packing rotor assembly into rotor assembly.At this moment, lodge in air in 35 grades of the 1st gap by radial bearing 11 outer circumferential face 117 and bearing support 15 inner peripheral surfaces between the 3rd gap 155 that forms discharge.The result is that lubricant oil is filled in the 115, the 3rd gap 155, the 35, the 2nd gap, the 111, the 1st gap, radial bearing gap, and also axial thrust bearing face 120 is supplied with.Like this, in case the rotor revolution, then the lubricant oil in radial bearing gap 111 circulates in radial bearing gap 111 via the 4th gap, the 115, the 1st gap 35, the 155, the 2nd gap, the 3rd gap that radial bearing 11 upper-end surfaces form.
Wherein, the outer circumferential side of the underpart 34 of turning axle 3 has only the 1st gap 35, no big space.Like this, even stretch out from the lower end surface 1 14 of radial bearing 11 underpart 34 of turning axle 3, there is not big space around the underpart 34 of turning axle 3, so under the state after the lubricant oil filling, the outer circumferential side of turning axle 3 underparts 34 (the 1st gap 35) is air accumulation not yet.Thus, outer circumferential face or radial bearing surface 110 at turning axle 3 are formed with man type chute and the concavo-convex occasion of taper, even the environment variation of temperature takes place, the air of the outer circumferential side of turning axle 3 underparts 34 can not expand or shrink yet, so lubricant oil can not discharged from radial bearing gap 111.Again, because of air does not enter the inside (radial bearing gap 111) of radial bearing 11, so motor characteristic is stable.
Again, though in supply after the lubricant oil, do not have big space around the underpart 23 because of turning axle 3, so the major part of the lubricant oil of supply can not accumulate in this part.And, the outer circumferential side of radial bearing 11 is communicated with radial bearing gap 111 by the 2nd gap 115 and the 1st gap 35, but because the size in these gaps has above-mentioned magnitude relationship, therefore the lubricant oil that lodges in radial bearing 11 outer circumferential sides utilizes wicking to be introduced into the 1st gap 35 through the 2nd gap 115, and the lubricant oil that is introduced into the 1st gap 35 utilizes wicking to be introduced into radial bearing gap 111.Like this, so the state after the lubricant oil in radial bearing gap 111 is in filling always is the reliability height of oil dynamic bearing means 10.
And,, therefore need not use lubricating grease because lubricant oil also enters thrust bearing surface 120 all the time.Thereby the assembling procedure of oil dynamic bearing means 10 is oversimplified.
Again, in the present embodiment, the upper-end surface of radial bearing 11 is formed with oil circulation groove 118, and the lower end surface 114 of radial bearing 11 is flat condition, does not need to form the groove of oily path.Like this, during assembling oil dynamic bearing means 10, because of can be, so can avoid with radial bearing reverse configuration about in the of 11 according to the differentiation that has the slotless diameter about bearing 11 is made.
[embodiment 2]
Fig. 3 (A), (B), (C) are respectively the oil dynamic bearing means sectional view of the embodiment of the invention 2, the amplification half sectional view of the end portion periphery of turning axle and the stereogram of use therein liner.In addition, the basic structure of embodiment 2,3 oil dynamic bearing means is identical with embodiment 1, so at general part mark prosign, omit detailed explanation.
Shown in Fig. 3 (A), (B), (C), the oil dynamic bearing means 10 of present embodiment also comprises: be separated with radial bearing gap 111 and be the radial bearing 11 of subtend with respect to the outer circumferential face of turning axle 3; And the thrust-bearing 12 of the lower end surface 38 of supporting rotating shaft 3.Wherein, on the outer circumferential face of turning axle 3 or radial bearing surface 110, be formed with dynamic pressure occurrence groove or the lambdoid dynamic pressure occurrence groove that the taper groove that extended by axial direction constitutes.
Again, oil dynamic bearing means 10 has the bearing support 15 that is fixed in motor framework 2, and radial bearing 11 is pressed in the bearing mounting hole 150 that is fixed on this bearing support 15.Wherein, the outer circumferential face 117 of radial bearing 11 is in the state that axial direction is formed with gap (the 3rd gap 155) with the inner peripheral surface of the bearing mounting hole 150 of bearing support 15.
The oil dynamic bearing means 10 of present embodiment also is that sphere is processed in the underpart 38 of turning axle 3, be formed with edge 30 at the sphere of the underpart 34 of turning axle 3 and the boundary part of pole part, in order to make the outside that is positioned at radial bearing 11 with the considerable part at the edge 30 of turning axle 3, stretch out with institute's sizing from the lower end surface 114 of radial bearing 11 underpart 34 of turning axle 3.
Again, present embodiment also is the ring-type liner 19 (adjustment part, gap) that is fixed with subtend in the configuration of the inboard of bearing support 15, this liner 19 both was separated with the 1st gap 35 and was subtend with respect to underpart 34 outer circumferential faces of turning axle 3, again and be formed with the 2nd gap 115 between the lower end surface 114 of radial bearing 11.
In the present embodiment, the upper-end surface 195 of liner 19 is flat condition, and the lower end surface 114 of radial bearing 11 is formed with the groove 199 that the degree of depth is size C, utilizes this groove 199 to be formed with the 2nd gap 115.
In the oil dynamic bearing means of this structure, liner 19 and radial bearing 11 be designed to following form promptly, when the size in the 115, the 3rd gap 155, the 35, the 2nd gap, the 111, the 1st gap, radial bearing gap is respectively A, B, C, D, the relation of the A in the present embodiment, B, C, D should satisfy A<B<C≤D.
Like this, the outer circumferential side of the oil dynamic bearing means 10 in the present embodiment in the underpart 34 of turning axle 3 has only the 1st gap 35, no big space.Thus, even stretch out from the lower end surface 114 of radial bearing 11 underpart 34 of turning axle 3, there is not big space around the underpart 34 of turning axle 3, so under the state after the lubricant oil filling, the outer circumferential side of turning axle 3 underparts 34 (the 1st gap 35) is air accumulation not yet.Therefore, outer circumferential face or radial bearing surface 110 at turning axle 3 are formed with man type chute or the concavo-convex occasion of taper, even the environment variation of temperature takes place, the air of the outer circumferential side of turning axle 3 underparts 34 can not expand or shrink yet, so lubricant oil can not discharged from radial bearing gap 111.Again, because of air does not enter the inside (radial bearing gap 111) of radial bearing 11, so identical with embodiment 1 effect at aspects such as motor characteristic are stable.
[embodiment 3]
Fig. 4 (A), (B), (C) are respectively the oil dynamic bearing means sectional view of the embodiment of the invention 3, the amplification half sectional view of the end portion periphery of turning axle and the stereogram of use therein liner.Shown in Fig. 4 (A), (B), (C), the oil dynamic bearing means 10 of present embodiment also comprises: be separated with radial bearing gap 111 and be the radial bearing 11 of subtend with respect to the outer circumferential face of turning axle 3; And the thrust-bearing 12 of the lower end surface 38 of supporting rotating shaft 3.
Oil dynamic bearing means 10 has the bearing support 15 that is fixed in motor framework 2, and radial bearing 11 is pressed in the bearing mounting hole 150 that is fixed on this bearing support 15.Wherein, the outer circumferential face 117 of radial bearing 11 is in the state that axial direction is formed with gap (the 3rd gap 155) with the inner peripheral surface of the bearing mounting hole 150 of bearing support 15.
The oil dynamic bearing means 10 of present embodiment also is that sphere is processed in the underpart 38 of turning axle 3, be formed with edge 30 at the sphere of the underpart 34 of turning axle 3 and the boundary part of pole part, in order to make the outside that is positioned at radial bearing 11 with the considerable part at the edge 30 of turning axle 3, stretch out with institute's sizing from the lower end surface 114 of radial bearing 11 underpart 34 of turning axle 3.
Again, present embodiment also is the ring-type liner 19 (adjustment part, gap) that is fixed with subtend in the configuration of the inboard of bearing support 15, this liner 19 both was separated with the 1st gap 35 and was subtend with respect to underpart 34 outer circumferential faces of turning axle 3, again and be formed with the 2nd gap 115 between the lower end surface 114 of radial bearing 11.
In the present embodiment, the upper-end surface 195 of liner 19 and the lower end surface 114 of radial bearing 11 all are flat condition, but are configured and are formed with the 2nd gap 115 by the interval with size C.
In the oil dynamic bearing means 10 of this structure, liner 19 be designed to following form promptly, when the size in the 115, the 3rd gap 155, the 35, the 2nd gap, the 111, the 1st gap, radial bearing gap is respectively A, B, C, D, the relation of the A in the present embodiment, B, C, D should satisfy A<B<C≤D.
Like this, the outer circumferential side of the oil dynamic bearing means 10 in the present embodiment in the underpart 34 of turning axle 3 has only the 1st gap 35, no big space.Thus, even stretch out from the lower end surface 114 of radial bearing 11 underpart 34 of turning axle 3, there is not big space around the underpart 34 of turning axle 3, so under the state after the lubricant oil filling, the outer circumferential side of turning axle 3 underparts 34 (the 1st gap 35) is air accumulation not yet.Therefore, outer circumferential face or radial bearing surface 110 at turning axle 3 are formed with man type chute or the concavo-convex occasion of taper, even the environment variation of temperature takes place, the air of the outer circumferential side of turning axle 3 underparts 34 can not expand or shrink yet, so lubricant oil can not discharged from radial bearing gap 111.Again, because of air does not enter the inside (radial bearing gap 111) of radial bearing 11, so identical with embodiment 1 effect at aspects such as motor characteristic are stable.
[other embodiment]
The foregoing description is the liner 19 that has disposed as the adjustment part, gap, but a part that for example also can be used as bearing support 15 forms the adjustment part, gap and do not use other member.