KR20140087141A

KR20140087141A - Spindle motor

Info

Publication number: KR20140087141A
Application number: KR1020120155290A
Authority: KR
Inventors: 비아체슬라브 스미르노프
Original assignee: 삼성전기주식회사
Priority date: 2012-12-27
Filing date: 2012-12-27
Publication date: 2014-07-09

Abstract

A spindle motor according to one embodiment of the present invention includes a rotating member which includes a shaft which includes a fixing groove on a lower side thereof, a hub base which is extended from the upper end of the shaft to the outer side of a radial direction, and a magnet support unit which is extended from the outer end of the hub base to the lower side of an axial direction; a sleeve which rotationally supports the rotating member to rotate and includes a receiving groove which is recessed to the lower side of the axial direction on an upper side thereof; and a stopper member which includes a fixing unit which is inserted into the fixing groove and a flange part which is extended from the fixing unit to the outer side of the radial direction, wherein, the hub base may include a protrusion part which protrudes from one side thereof and is received in the receiving groove.

Description

[0001] The present invention relates to a spindle motor,

The present invention relates to a spindle motor.

A hard disk drive (HDD), which is one of information storage devices, is a device that reproduces data stored on a disk using a read / write head or records data on a disk.

Such a hard disk drive requires a disk drive capable of driving the disk, and a spindle motor is used for the disk drive.

A fluid dynamic pressure bearing assembly is used as the spindle motor, and a lubricating fluid is interposed between the shaft, which is one of the rotating members of the fluid dynamic pressure bearing assembly, and the sleeve, which is one of the holding members, to support the shaft by fluid pressure generated in the lubricating fluid do.

Here, the lubricating fluid injected into the fluid dynamic pressure bearing assembly may be leaked to the outside or may be reduced in amount due to evaporation. Due to such a phenomenon, the fluid dynamic pressure bearing can not generate pressure, and the performance of the spindle motor And a problem occurs in the lifetime.

In addition, when an external impact or the like is applied during driving of the spindle motor, if deformation occurs in the internal components, the driving of the spindle motor is adversely affected. Therefore, it is important to secure the rigidity of the spindle motor.

Therefore, it is urgently required to improve the rigidity of the spindle motor so that internal components are not deformed even when an external impact is applied, and maximize performance and life span by securing a storage space for lubricating fluid.

An object of an embodiment of the present invention is to provide a spindle motor capable of improving the rigidity of a spindle motor and increasing the storage space of lubricating fluid.

Another object of the present invention is to provide a spindle motor that can reduce internal components of a spindle motor, simplify the manufacturing process, and reduce manufacturing cost.

A spindle motor according to an embodiment of the present invention includes a shaft having a lower fixing groove, a hub base extending radially outward from an upper end of the shaft, and a magnet supporting portion extending axially downward from an outer end of the hub base ; A sleeve rotatably supporting the rotating member and having a receiving groove which is axially downwardly inserted from the upper surface; And a stopper member having a fixing portion inserted into the fixing groove and a flange portion extending radially outward from the fixing portion, wherein the hub base is protruded from one surface of the hub base, May be provided.

A thrust dynamic pressure groove for generating thrust dynamic pressure may be formed on at least one of the upper surface of the sleeve of the spindle motor and the lower surface of the hub base opposite to the upper surface of the sleeve according to an embodiment of the present invention.

A lubricating fluid may be sealed between the inner circumferential surface of the protrusion of the spindle motor and the inner wall of the sleeve forming the receiving groove according to an embodiment of the present invention.

At least one of the inner circumferential surface of the protrusion of the spindle motor and the inner wall of the sleeve forming the receiving groove according to an embodiment of the present invention may be tapered to seal the lubricating fluid.

A lubricating fluid may be sealed between the outer circumferential surface of the protrusion of the spindle motor and the inner wall of the sleeve forming the receiving groove according to an embodiment of the present invention.

At least one of the inner circumferential surface, the lower surface, and the outer circumferential surface of the protrusion of the spindle motor according to an embodiment of the present invention may be tapered to seal the lubricating fluid.

The sleeve of the spindle motor according to an embodiment of the present invention may have a bypass flow path passing through the upper and lower portions of the sleeve.

The spindle motor may further include a base member coupled with the sleeve of the spindle motor according to an embodiment of the present invention and fixing the sleeve.

The base member of the spindle motor according to an embodiment of the present invention may be a steel plate plastically deformed.

According to another aspect of the present invention, there is provided a spindle motor including: a rotary member having a shaft, a hub base extending radially outward from an upper end of the shaft, and a magnet support portion extending axially downward from an outer end of the hub base; A shaft housing having a housing coupled to the shaft and a stopper portion extending radially outwardly from a lower portion of the housing; And a sleeve which rotatably supports the shaft and includes a receiving groove which is axially downwardly inserted from the upper surface, wherein the hub base is provided with a projection projecting from one surface of the hub base, the projection being received in the receiving groove .

In at least one of the outer circumferential surface of the housing and the inner circumferential surface of the sleeve of the spindle motor according to another embodiment of the present invention, a radial dynamic pressure groove for generating a radial dynamic pressure may be provided.

According to another aspect of the present invention, there is provided a spindle motor including: a rotary member having a shaft, a hub base extending radially outward from an upper end of the shaft, and a magnet support portion extending axially downward from an outer end of the hub base; A stopper portion engaged with a lower portion of the shaft; And a sleeve which rotatably supports the shaft and includes a receiving groove which is axially downwardly inserted from the upper surface, wherein the hub base is provided with a projection projecting from one surface of the hub base, the projection being received in the receiving groove .

According to the spindle motor according to the present invention, the rigidity of the spindle motor can be improved and the storage space of the lubricating fluid can be increased.

In addition, the internal components of the spindle motor can be reduced to simplify the manufacturing process and reduce the manufacturing cost.

1 is a schematic sectional view of a spindle motor according to a first embodiment of the present invention;
2 is an enlarged cross-sectional view of a portion A in Fig.
3 is a half sectional view showing a modified example of a tapered structure for sealing a lubricating fluid in a spindle motor according to a first embodiment of the present invention.
4 is a half sectional view showing a modified example of a tapered structure for sealing a lubricating fluid in a spindle motor according to a first embodiment of the present invention.
5 is a half sectional view showing a modified example of the sealing position of the lubricating fluid in the spindle motor according to the first embodiment of the present invention.
6 is a half sectional view showing a modified example of the sealing position of the lubricating fluid in the spindle motor according to the first embodiment of the present invention.
7 is a half sectional view showing a modification of the bypass flow path in the spindle motor according to the first embodiment of the present invention.
8 is a half sectional view showing a modification of the bypass flow path in the spindle motor according to the first embodiment of the present invention.
9 is a half sectional view showing a modification of the bypass flow path in the spindle motor according to the first embodiment of the present invention.
10 is a half sectional view of a spindle motor according to a second embodiment of the present invention.
11 is a half sectional view showing a modified example of a sealing position of a lubricating fluid in a spindle motor according to a second embodiment of the present invention.
12 is a half sectional view of a spindle motor according to a third embodiment of the present invention;

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept. Other embodiments falling within the scope of the inventive concept may readily be suggested, but are also considered to be within the scope of the present invention.

The same reference numerals are used to designate the same components in the same reference numerals in the drawings of the embodiments.

FIG. 1 is a schematic sectional view of a spindle motor according to a first embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a portion A of FIG.

3 and 4 are half sectional views showing a modification of the tapered structure for sealing the lubricating fluid in the spindle motor according to the first embodiment of the present invention.

5 and 6 are half sectional views showing a modification of the sealing position of the lubricating fluid in the spindle motor according to the first embodiment of the present invention.

7 to 9 are half sectional views showing a modified example of the bypass flow path in the spindle motor according to the first embodiment of the present invention.

1 to 9, a spindle motor according to a first embodiment of the present invention may include a fluid dynamic pressure bearing assembly 100 and a stator 300 as a fixing member.

1, the axial direction refers to the vertical direction with respect to the shaft 111, and the radially outer or inner direction refers to the direction of the shaft 111, Or the center of the shaft 111 with respect to the outer end of the shaft 111 or the outer end of the shaft 111. [

The hydrodynamic bearing assembly 100 may include a rotating member 110 that includes a shaft 111, a sleeve 120, and a cover plate 130.

The shaft 111 can constitute the rotating member 110 together with the hub base 113 and the magnet supporting portion 115 and can rotate relative to the fixing member.

The rotary member 110 includes the shaft 111 inserted into the shaft hole of the sleeve 120, the hub base 113 extending radially outward from the upper end of the shaft 111, And a magnet supporting portion 115 extending axially downward from the outer end.

In the spindle motor according to the first embodiment of the present invention, the shaft 111, the hub base 113, and the hub base 113 and the magnet supporting portion are provided as separate members, And the magnet supporting portion 115 may be integrally formed to constitute the rotary member 110. [

Repeatable run out (RRO) can be reduced when the shaft 111, the hub base 113 and the magnet supporter 115 are integrally formed to constitute the rotary member 110, Can be minimized to maximize performance.

Also, in the case where the separate members are coupled to each other to constitute the rotating member, when an external impact or the like is applied, the coupling parts between the members may be impacted and deformation of the internal components may occur. However, in the first embodiment of the present invention The shaft 111, the hub base 113, and the magnet supporter 115 are integrally formed in the spindle motor, so that deformation of internal components can be suppressed even if an external impact or the like is applied.

The rotating member 110 is a rotating structure rotatably provided with respect to the stator 300 and may include a ring-shaped magnet 150 corresponding to the core 330 at a predetermined interval, have.

The magnet support portion 115 of the rotary member 110 is axially bent downward from the hub base 113 to support the magnet 150.

The magnet 150 is provided as a permanent magnet which alternately magnetizes N and S poles in a circumferential direction to generate magnetic force of a predetermined intensity.

When the coil 320 wound on the core 330 is supplied with power, the magnet 150 and the coil 320 are wound on the core 330 wound with the coil 330. [ So that a driving force capable of rotating the rotary member 110 is generated.

As a result, the rotating member 110 rotates relative to the fixed member.

The hub base 113 constituting the rotary member 110 may be provided with a protrusion 117 protruding downward in the axial direction from one surface of the hub base 113.

The protrusion 117 may be received in a receiving groove 121 formed in the sleeve 120 as a fixing member and a lubricating fluid may be sealed between the protruding portion 117 and the receiving groove 121.

This will be described later in detail.

The sleeve 120 may support the shaft 111 such that the shaft 111 is rotatable and may be formed by forging Cu or Al or sintering a Cu-Fe alloy powder or an SUS powder .

Here, the shaft 111 is inserted into the shaft 120 so as to have a minute clearance with the shaft, and the minute clearance is filled with a lubricating fluid, and at least the outer diameter of the shaft 111 and the inner diameter of the sleeve 120 The rotation of the shaft 111 can be more smoothly supported by the radial dynamic pressure grooves (not shown) formed in one.

The radial dynamic pressure groove may be formed on an inner circumferential surface of the sleeve 120 inside the shaft hole of the sleeve 120. When the shaft 111 rotates, 120, so as to smoothly rotate.

However, the radial dynamic pressure grooves (not shown) are not limited to those provided on the inner circumferential surface of the sleeve 120, but may be provided on the outer circumferential surface of the shaft 111, .

The radial dynamic pressure grooves (not shown) may be any one of a herringbone shape, a spiral shape, and a thread shape, and any shapes that generate radial dynamic pressure are not limited.

A thrust dynamic pressure groove (not shown) may be formed on at least one of the upper surface of the sleeve 120 and the hub base 113 of the rotating member facing the upper surface of the sleeve 120, The shaft 111 can be rotated with a certain levitation force secured by a dynamic pressure groove (not shown).

The shape of the thrust dynamic pressure groove (not shown) may be a herringbone shape, a spiral shape, or a thread groove like the radial dynamic pressure groove (not shown), but the shape is not necessarily limited to this, It can be applied.

At least one bypass flow path 123 may be formed in the sleeve 120 to communicate the upper and lower portions of the sleeve 120.

The bypass passage 123 may be formed in various shapes so as to communicate the upper portion and the lower portion of the sleeve 120.

That is, as shown in FIGS. 7 to 9, the bypass passage 123 may be formed in various shapes if it has a shape communicating the upper portion and the lower portion of the sleeve 120.

The bypass passage 123 can distribute the pressure of the lubricating fluid to maintain the balance, and the bubbles or the like existing in the lubricating fluid can be moved to be discharged by circulation.

The receiving groove 121 may be formed in the upper surface of the sleeve 120 so as to be inserted into the receiving groove 121. The receiving groove 121 may be formed in the upper surface of the hub base 113, 117 may be accommodated.

A U-shaped micro gap may be formed between the projecting portion 117 and the receiving groove 121 by the projecting portion 117 and the receiving groove 121, A lubricating fluid may be sealed between the inner circumferential surface of the sleeve 120 and the inner circumferential surface of the sleeve 120 forming the receiving groove 121. [

2 to 4, at least one of the inner circumferential surface of the protrusion 117 and the inner wall of the sleeve 120 forming the receiving groove 121 may be tapered.

However, the sealing position of the lubricating fluid is not limited between the inner circumferential surface of the projection 117 and the inner wall of the sleeve 120 forming the receiving groove 121.

5 and 6, the lubricating fluid may be sealed between the outer circumferential surface of the protrusion 120 and the inner wall of the sleeve 120 forming the receiving groove 121. In this case, At least one of the outer circumferential surface of the projection 117 and the inner wall of the sleeve 120 forming the receiving groove 121 may be tapered.

Also, at least one of the inner circumferential surface, the lower surface and the outer circumferential surface of the protrusion 117 may be tapered to seal the lubricating fluid.

When the lubrication fluid is sealed at the outermost minute gap in the radial direction among the substantially U-shaped minute gaps formed between the projecting portion 117 and the receiving groove 121, .

During the operation of the spindle motor, the lubricating fluid may gradually decrease due to the leakage or evaporation of the lubricating fluid, thereby failing to provide sufficient fluid pressure, which may seriously affect the drive of the spindle motor. However, As a result, the life span of the spindle motor can be increased.

Further, when the interface of the lubricating fluid moves radially inward due to the evaporation of the lubricating fluid, even if the lubricating fluid leaks out of the interface due to an external impact or the like, the lubricating fluid is sealed again by the tapered structure existing outside It is also possible.

Therefore, leakage of the lubricating fluid can be effectively prevented.

A fixing groove 119 may be formed in the lower portion of the shaft 111 and a stopper member 130 may be fixedly coupled to the fixing groove 119.

The stopper member 130 may include a fixing portion 131 inserted into the fixing groove 119 and a flange portion 133 extending radially outward from the fixing portion 131.

The flange portion 133 may be received in a stepped portion formed at a lower portion of the sleeve 120.

Therefore, when the shaft 111 as the rotary member 110 is overloaded, the upper surface of the flange portion 1330 is caught by the lower surface of the sleeve 120 to prevent the rotary member 110 from being overloaded .

A thrust dynamic pressure groove (not shown) may be formed on at least one of the lower surface of the sleeve 120 and the upper surface of the flange portion 133 facing the lower surface of the sleeve 120, The shaft 111 can be rotated with a certain levitation force secured.

The cover plate 140 can be engaged with the sleeve 120 while maintaining a gap between the shaft 111 and the lower portion of the sleeve 120.

The cover plate 140 may receive a lubricating fluid in a gap formed between the cover plate 140 and the sleeve 120 to support the lower surface of the shaft 111.

At this time, the cover plate 140 may be fixed by various methods such as welding, caulking, or bonding, which can be selectively applied according to the structure and process of the product.

The stator 300 may include a coil 320, a core 330, and a base member 310.

The stator 300 is a fixed structure having a core 330 on which a coil 320 for generating an electromagnetic force having a predetermined magnitude when the power is applied is wound.

The core 330 is fixedly disposed on a base member 310 provided with a printed circuit board (not shown) on which a pattern circuit is printed, and the core 330, on which the coil 320 is wound, A plurality of coil holes of a predetermined size may be formed on the upper surface of the member 310 to expose the coil 320 downward. The coil 320 may be connected to the printed circuit board (not shown) Respectively.

The base member 310 may be made of aluminum by die casting, but it may be manufactured by plastic working (e.g., pressing) a steel sheet.

FIG. 10 is a half sectional view of a spindle motor according to a second embodiment of the present invention, and FIG. 11 is a half sectional view showing a modified example of a sealing position of a lubricating fluid in a spindle motor according to a second embodiment of the present invention.

10 and 11, the spindle motor according to the second embodiment of the present invention is the same as the spindle motor according to the first embodiment of the present invention except for the shaft housing 130 ', and thus the shaft housing 130 'Will be omitted.

The shaft housing 130 'may have a hollow cylindrical shape, and the shaft 111 may be inserted and fixed to the hollow of the shaft housing 130'.

That is, in the spindle motor according to the second embodiment of the present invention, the shaft 111 is fixed to the shaft housing 130 ', thereby forming the rotating member 110 together with the shaft housing 130'.

Specifically, the shaft housing 130 'may include a housing 131' coupled with the shaft 111 and a stopper 133 'extending radially outward from the lower end of the housing 131' have.

Here, the shaft housing 130 'is inserted with a shaft hole of the sleeve 120 so as to have a minute clearance, and a lubricating fluid is filled in the minute gap, and the outer diameter of the housing 131' The rotation of the rotary member 110 can be more smoothly supported by the radial dynamic pressure grooves (not shown) formed on at least one of the inner diameters.

The radial dynamic pressure groove (not shown) may be formed on the inner circumferential surface of the sleeve 120 inside the shaft hole of the sleeve 120. When the rotary member 110 rotates, the housing 131 ' And is spaced apart from the inner circumferential surface of the sleeve 120 by a predetermined distance to form a pressure so as to smoothly rotate.

However, the radial dynamic pressure grooves (not shown) are not limited to those provided on the inner circumferential surface of the sleeve 120, but may be provided on the outer circumferential surface of the housing 131 ' It is not clear.

The stopper 133 'may be received in a stepped portion formed at a lower portion of the sleeve 120.

Therefore, when the shaft 111 and the shaft housing 130 'as the rotary member 110 are overloaded, the upper surface of the stopper 133' is caught by the lower surface of the sleeve 120, It is possible to prevent overloading of the light emitting diode 110.

A thrust dynamic pressure groove (not shown) may be formed on at least one of the upper surface of the sleeve 120 and the upper surface of the stopper 133 'that faces the upper surface of the sleeve 120, (Not shown), the rotating member 110 can rotate with a certain levitation force secured.

12 is a half sectional view of a spindle motor according to a third embodiment of the present invention.

Referring to FIG. 12, the spindle motor according to the third embodiment of the present invention is the same as the spindle motor according to the first embodiment of the present invention, except for the stopper portion 130 ''. ) Will be omitted.

In the spindle motor according to the third embodiment of the present invention, the stopper portion 130 '' can be engaged with the lower portion of the shaft 111.

A hole may be formed at the center of the stopper portion 130 '' so that the lower portion of the shaft 111 may be inserted into the hole.

Since the stopper portion 130 '' can be accommodated in the stepped portion formed at the lower portion of the sleeve 120, when the shaft 111 as the rotating member 110 is overloaded, the stopper portion 130 ' 'May be caught by the lower surface of the sleeve 120 to prevent an excessive load on the rotary member.

A thrust dynamic pressure groove (not shown) may be formed on at least one of the upper surface of the sleeve 120 and the upper surface of the stopper 130 '', which faces the upper surface of the sleeve 120, The rotary member 110 can be rotated with a certain lifting force by grooves (not shown).

Through the above-described embodiments, the spindle motor according to the present invention can improve the rigidity, increase the storage space of the lubricating fluid, reduce the internal components of the spindle motor, and simplify the manufacturing process and reduce the manufacturing cost .

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be apparent to those skilled in the art that such modifications or variations are within the scope of the appended claims.

100: fluid dynamic pressure bearing assembly 110: rotating member
111: shaft 113: hub base
115: Magnet supporter 117:
119: fixing groove 120: sleeve
121: receiving groove 123: bypass channel
130: stopper member 131:
133: flange portion 140: cover plate
150: Magnet 300: Stator
310: base member 320: coil
330: Core

Claims

A rotary member having a shaft having a lower fixing groove, a hub base extending radially outward from an upper end of the shaft, and a magnet supporting portion extending axially downward from an outer end of the hub base;
A sleeve rotatably supporting the rotating member and having a receiving groove which is axially downwardly inserted from the upper surface; And
And a stopper member having a fixing portion inserted into the fixing groove and a flange portion extending radially outward from the fixing portion,
Wherein the hub base is provided with a projection projecting from one surface of the hub base and received in the receiving groove.

The method according to claim 1,
Wherein at least one of the upper surface and the lower surface of the sleeve has thrust dynamic pressure grooves for generating thrust dynamic pressure.

The method according to claim 1,
And a lubricating fluid is sealed between the inner peripheral surface of the protrusion and the inner wall of the sleeve forming the receiving groove.

The method of claim 3,
Wherein at least one of an inner circumferential surface of the protrusion and an inner wall of the sleeve forming the receiving groove is tapered to seal the lubricating fluid.

The method according to claim 1,
And a lubricating fluid is sealed between the outer peripheral surface of the projection and the inner wall of the sleeve forming the receiving groove.

6. The method of claim 5,
And at least one of an inner circumferential surface, a lower surface, and an outer circumferential surface of the protrusion is tapered to seal the lubricating fluid.

The method according to claim 1,
And a bypass flow path penetrating the upper and lower portions of the sleeve is formed in the sleeve.

The method according to claim 1,
And a base member coupled to the sleeve and fixing the sleeve.

9. The method of claim 8,
Wherein the base member is formed by plastically deforming the steel plate.

A rotary member having a shaft, a hub base extending radially outward from an upper end of the shaft, and a magnet support extending axially downward at an outer end of the hub base;
A shaft housing having a housing coupled to the shaft and a stopper portion extending radially outwardly from a lower portion of the housing; And
And a sleeve rotatably supporting the shaft and having a receiving groove that is axially downwardly received from the upper surface,
Wherein the hub base is provided with a projection projecting from one surface of the hub base and received in the receiving groove.

11. The method of claim 10,
Wherein at least one of an outer circumferential surface of the housing and an inner circumferential surface of the sleeve is provided with a radial dynamic pressure groove for generating a radial dynamic pressure.

A rotary member having a shaft, a hub base extending radially outward from an upper end of the shaft, and a magnet support extending axially downward at an outer end of the hub base;
A stopper portion engaged with a lower portion of the shaft; And
And a sleeve rotatably supporting the shaft and having a receiving groove that is axially downwardly received from the upper surface,
Wherein the hub base is provided with a projection projecting from one surface of the hub base and received in the receiving groove.