KR20130043973A

KR20130043973A - Spindle motor

Info

Publication number: KR20130043973A
Application number: KR1020110108195A
Authority: KR
Inventors: 박영하
Original assignee: 삼성전기주식회사
Priority date: 2011-10-21
Filing date: 2011-10-21
Publication date: 2013-05-02

Abstract

PURPOSE: A spindle motor is provided to locate a lower end of a fixing member in a place which is lower than a lower end of a thrust plate when the fixing member and the rotation axis are connected by using a screw, thereby increasing rigidity. CONSTITUTION: A rotation unit includes a fixing plate and a fixing member(190). The fixing plate fixes a disk which is mounted in a hub(120). The fixing member fixes the fixing plate to the rotation unit. The fixing member is connected to a rotation axis(110) by using a screw. A lower end of the fixing member is located in a place which is lower than a lower end of a thrust plate(140) which is connected to the rotation axis.

Description

Spindle Motor

The present invention relates to a spindle motor.

In general, a spindle motor used as a driving device for a recording disk such as a hard disk has a lubricating fluid such as oil stored between a rotating part and a fixed part at the time of rotation of the motor. It is used in various ways.

More specifically, a spindle motor equipped with a fluid dynamic pressure bearing that maintains axial rigidity of the shaft only by the moving pressure of the lubricating oil by centrifugal force is based on the thrust force. Therefore, there is no metal friction, And it is mainly applied to high-end optical disc apparatuses and magnetic disc apparatuses, since the high-speed rotation of the rotating object is smoother than the motor having the ball bearing.

And the spindle motor having a hydrodynamic bearing according to the prior art is coupled to the fixed screw to the rotating shaft to press the fixed plate for fixing the disk mounted on the hub, the thrust plate is coupled to the rotating shaft. In this case, in order to screw the fixing screw to the rotating shaft, the screw must be threaded on the rotating shaft, and the rotating shaft is damaged by the tensile force of the fixing screw.

The present invention has been made to solve the above problems, in the spindle motor, when the fixing member is screwed to the rotating shaft, the lower end of the fixing member to the rotating shaft with respect to the axial direction of the rotating shaft thrust is coupled to the rotating shaft As located below the lower end of the plate, the rigidity is increased to provide a spindle motor that can prevent the destruction of the rotating shaft.

The present invention provides a rotating part including a rotating shaft, a hub, a magnet, and a thrust plate coupled to the rotating shaft, a sleeve for rotatably supporting the rotating shaft, a base to which the sleeve is coupled, and a magnet opposed to and fixed to the base. And a spindle motor including an armature made of a core and a coil, and filled with oil to form a hydrodynamic bearing part between the rotor and the rotor, wherein the rotor is configured to fix a disk mounted on a hub. And a fixing member for fixing the fixing plate and the fixing plate to the rotating part, wherein the fixing member is screwed to the rotating shaft, and the lower end of the fixing member is coupled to the rotating shaft relative to the rotating shaft with respect to the axial direction of the rotating shaft. It is located below the lower part.

In addition, the fixing member includes a head for pressing the fixing plate, and a screw for screwing to the rotating shaft.

In addition, the rotating shaft is formed with a thread processing portion corresponding to the screw portion of the fixing member.

In addition, the hub is a cylindrical portion fixed to the upper end of the rotating shaft, a disk portion extending radially outward from the cylindrical portion, a side wall portion extending downward in the axial direction of the rotation shaft at the radially outer end of the disk portion, A support portion extending radially outwardly of the side wall portion parallel to the disc portion, wherein the disk is coupled to the side wall portion and supported by the support portion with respect to the axial direction of the axis of rotation, the upper portion being supported by the fixing plate. Is pressurized.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to that, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may properly define the concept of the term in order to best explain its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to the present invention, in the spindle motor, when the fixing member is screwed to the rotary shaft, the lower end of the fixing member to the rotary shaft with respect to the axial direction of the rotary shaft is located below the lower end of the thrust plate coupled to the rotary shaft, the rigidity This increases to obtain a spindle motor that can prevent the destruction of the rotating shaft.

1 is a cross-sectional view schematically showing a spindle motor according to an embodiment of the present invention.
2 is a schematic partial exploded cross-sectional view of the spindle motor shown in FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The objectives, specific advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. It will be further understood that terms such as " first, "" second," " one side, "" other," and the like are used to distinguish one element from another, no. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the present invention, detailed description of related arts which may unnecessarily obscure the gist of the present invention will be omitted.

Hereinafter, exemplary embodiments of the spindle motor according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view schematically showing a spindle motor according to an embodiment of the present invention, Figure 2 is a schematic partial exploded cross-sectional view of the spindle motor shown in FIG. As shown in the drawing, the spindle motor 100 includes a rotating part including a rotating shaft 110, a hub 120, a magnet 130, a thrust plate 140, and a fixing member 190, a sleeve 150, and a base ( 160, the armature 170, the sealing member 180, the cover 151 is made up of a fixed portion, the working fluid is filled with oil to form a hydrodynamic bearing portion.

In the rotating unit, the hub 120 is coupled to the upper end of the rotating shaft 110, and a thrust plate 140 is formed to form a thrust dynamic pressure bearing part in a gap with the sleeve 150. In addition, the thread processing unit 111 is formed so that the fixing member 190 can be screwed. And the fixing plate (P) for fixing the disk (D) mounted on the hub 120 is located on the top of the hub.

And the fixing member 190 is formed with a screw portion 192 for being coupled to the head portion 191 for pressing the upper portion of the fixing plate (P) and the thread processing portion 111 of the rotary shaft (110).

In this way, while coupling the threaded portion 192 of the fixing member 190 to the thread processing portion 111 of the rotary shaft, the upper portion of the fixing plate (P) located on the upper portion of the hub of the fixing member 190 The pressure is fixed through the head 191.

At this time, as the lower end portion of the thread processing unit 111 to which the fixing member 190 is coupled is located below the orthogonal lower end portion of the rotation shaft of the thrust plate 140 coupled to the outer peripheral portion of the rotation shaft, as shown in FIG. 1. Likewise, the gap A is formed, and the fixing member is further inserted into the rotating shaft by the interval A, thereby preventing the rotating shaft from being broken by the tensile force by the fixing member.

In addition, the hub 120 is a cylindrical portion 121 fixed to the upper end of the rotating shaft 110, a disk portion 122 extending radially outward from the cylindrical portion 121, the radius of the disk portion 122 A side wall portion 123 extending downward in the axial direction of the rotation axis at a direction outer end, and a support portion 124 extending parallel to the disc portion 122 radially outward of the side wall portion 123, The disk is coupled to the side wall portion and supported by the support portion with respect to the axial direction of the axis of rotation.

In addition, the magnet 130 having an annular shape is mounted on an inner circumferential surface of the side wall part 123 so as to face the armature 160 including the core 161 and the coil 162.

Next, in the fixing part, the sleeve 150 supports the rotation shaft 110 to be rotatable, and the sleeve 150 is inserted and fixed to the inner circumference of the base 160.

The cover 151 is for sealing the oil injected to form the hydrodynamic bearing, and is fixed to the inner circumferential surface of the lower end of the sleeve 150.

In addition, the sealing member 180 is coupled to the sleeve 150, is positioned on the top of the thrust plate 140 coupled to the rotating shaft 110 to form an oil interface.

A radial hydrodynamic bearing unit (not shown), which is a hydrodynamic bearing unit, is formed between the sleeve 160 and the rotation shaft 110. More specifically, the radial dynamic bearing portion is a minute gap is formed between the rotating shaft 110 and the sleeve 150, the oil is filled in the minute gap is formed a radial dynamic bearing part.

To this end, the radial dynamic pressure bearing portion is formed by selectively forming a dynamic pressure generating groove (not shown) on the inner circumferential surface of the sleeve 150 and the outer circumferential surface of the rotating shaft 110 opposite thereto. In addition, two dynamic pressure generating grooves may be selectively formed at the upper and lower portions of the inner circumferential surface of the sleeve or at the upper and lower portions of the outer circumferential surface of the rotating shaft.

In addition, an armature 170 made of a core 171 and a coil 172 is fixed to the outer circumferential portion of the base 160 by pressing or bonding, so as to face the magnet 130, and an inner circumferential portion of the base 170. The sleeve 160 is fixed by indentation or adhesion.

Next, a pulling plate 161 is further mounted to the base 160 of the spindle motor 100 according to the present invention, and the pulling plate 161 is used to prevent injury of the hub 150. Positioned axially opposite 130.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be apparent that modifications and improvements can be made by those skilled in the art.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: spindle motor 110: rotation axis
120: hub 130: magnet
140: thrust plate 150: sleeve
151 cover 160 base
170: armature 180: sealing member
190: fixing member 191: head
192: Screw section

Claims

A rotating part including a rotating shaft, a hub, a magnet, and a thrust plate coupled to the rotating shaft, a sleeve for rotatably supporting the rotating shaft, a base to which the sleeve is coupled, and a magnet opposed to and fixed to the base, the core And a stationary part including an armature made of a coil, and filled with oil to form a hydrodynamic bearing part between the rotating part and the fixed part.
The rotating unit further includes a fixing plate for fixing the disk mounted on the hub and a fixing member for fixing the fixing plate to the rotating unit,
The fixing member is screwed to the rotating shaft, the lower end of the fixing member on the rotating shaft with respect to the axial direction of the rotating shaft, the spindle motor, characterized in that located below the lower end of the thrust plate coupled to the rotating shaft.

The method according to claim 1,
The fixing member
Head for pressing the fixing plate; And
Spindle motor, characterized in that it comprises a screw for screwing to the rotating shaft.

The method according to claim 2,
The rotating shaft is a spindle motor, characterized in that the thread processing portion corresponding to the threaded portion of the fixing member is formed.

The method according to claim 1,
The hub
A cylindrical part fixed to an upper end of the rotating shaft;
A disc portion extending radially outward from the cylinder portion;
A side wall portion extending downward in the axial direction of the rotation shaft at a radially outer end of the disc portion; And
A support portion extending radially outwardly of the side wall portion parallel to the disc portion, wherein the disk is coupled to the side wall portion and supported by the support portion with respect to the axial direction of the axis of rotation, the upper portion being supported by the fixing plate. Spindle motor, characterized in that the pressurized.