WO2013089351A1

WO2013089351A1 - Spindle motor

Info

Publication number: WO2013089351A1
Application number: PCT/KR2012/009436
Authority: WO
Inventors: 이정훈
Original assignee: 주식회사 삼홍사
Priority date: 2011-12-15
Filing date: 2012-11-09
Publication date: 2013-06-20
Also published as: KR20130067992A; KR101322357B1

Abstract

The present invention relates to a low-cost spindle motor that is capable of securing the verticality of a bearing and a rotation shaft which are assembled in a bearing housing and has a simple turntable structure. The spindle motor includes: a turntable on which a recording medium having a disk shape is attached or detached; a rotor including a rotor yoke on which a plurality of magnets are mounted, wherein the rotor yoke has a protrusion portion having an upper middle portion thereof on which a central portion of the turntable is coupled, and the rotational shaft is press-fitted into the center of the protrusion portion; a bearing housing formed of a resin, the bearing housing having a through hole in which the rotation shaft is inserted; a pair of bearings disposed at a distance from one another in the through hole in the bearing housing in order to rotatably support the rotation shaft; and a stator coupled to an outer diameter portion of the bearing housing so as to face the rotor, wherein the stator generates electromagnetic fields when a driving signal is applied, and thus rotates the rotor.

Description

Spindle motor

The present invention relates to a spindle motor, in particular, to reduce the unit cost of the product by omitting expensive center free bearings, forming a bearing housing made of resin, and inserting the base plate into the bearing housing, Alternatively, by integrating with the bearing housing by bonding or the like, it is possible to secure the verticality of the bearing and the rotating shaft assembled therein. In addition, the turntable is directly press-assembled into the rotor yoke and a magnet that sucks the chucking device on the upper side of the rotor yoke. As the chucking is provided, the structure of the turntable relates to a simple spindle motor.

In general, optical disc players such as LDP, CDP, CD-ROM and DVD-ROM players, DVD players, BDs, 3D players, etc., clamp a mounting hole formed in the center of the disc while loading the disc on the turntable by a loading mechanism. Clamping and fixing as a chuck as a unit, and reproducing the information recorded on the disk by an optical pickup unit which moves in a radial direction while rotating the disk clamped to the chuck in one direction by a drive source of a spindle motor as a driving means. Device.

The spindle motor maintains a constant contact section between the bearing and the rotating shaft to rotatably support the rotating shaft, thereby maintaining a high accuracy of rotation characteristics, thereby enabling hard disk drive (HDD), optical disk drive (ODD) and other high speed rotation. It is widely employed as a driving means of a desired recording medium.

Spindle motors that require such high speed rotation are required to be thinner and lighter to meet the development of electronic devices that are miniaturized daily. An example of such a spindle motor is schematically illustrated in FIG. 1.

1 is a cross-sectional view of a conventional half height spindle motor. As shown in the drawing, the conventional spindle motor 10 has a bearing housing in a coupling protrusion 11a having a coupling hole formed in the base plate 11. The outer peripheral surface of the lower end part of (13) is press-fitted. A stopper 14 for preventing separation of the rotation shaft 19 is coupled to the inner circumferential surface of the lower end side of the bearing housing 13.

A center free bearing 17 is fixed to the inside of the bearing housing 13, and a rotation shaft 19 is supported on the center free bearing 17 so as to be rotatable, and a lower end of the rotation shaft 19 A support washer 16 for reducing the rotational resistance of the rotary shaft 19 is arranged in the recess of the bottom of the bearing housing 13. The center free bearing 17 is an expensive bearing containing oil to minimize friction with the rotating shaft 19 that rotates at high speed.

In addition, the stator 21 having the core 21a and the coil 21b is fixed to the outer circumferential surface of the bearing housing 13, and the rotor yoke 23a is fixed to a portion adjacent to the center from the distal end of the rotation shaft 19. The rotor 23 having the magnet 23b is fixed to the inner circumferential surface of the rotor yoke 23a.

In this case, the thrust magnet 25 is attached to the rotor yoke 23a adjacent to the upper end of the bearing housing 13. As a result, the bearing housing 13 acts as a yoke corresponding to the thrust magnet 25, thereby mutually attracting the thrust magnet 25 and the magnetic force, thereby causing the shaft of the rotor 23 to rotate when the rotor 23 is rotated. Prevent directional injury and flow.

The turntable 27 on which the disk D is seated is provided with a coupling hole 27a into which the leading end of the rotation shaft 19 is inserted. At this time, an adhesive is applied to the inner circumferential surface of the coupling hole 27a to bond between the turntable 27 and the rotation shaft 19.

The turntable 27 is provided with a rubber ring 27b for preventing the slit of the disk D outside the upper surface, and a plurality of bosses 28 are formed around the coupling hole 27a inside the turntable 27. (See FIG. 2). The boss 28 is fusion-processed after the end of the boss 28 is inserted into the through hole 29a of the yoke 29 so as to fix the ring yoke 29 above the turntable 27. The yoke 29 magnetically couples with the magnet 33 of the chucking device 30, thereby preventing the disk D from rising or falling off. Further, the turntable 27 is formed with a plurality of jaws 27c arranged at predetermined intervals so as to suppress the lateral movement of the disk D by the elastic force.

In addition, the disk drive includes a chucking device including a disk chuck 31 that operates in a vertical direction and a magnet 33 installed inside the disk chuck 31 so as to prevent the disk D mounted on the turntable 27 from rising. 30 is provided. The disk chuck 31 presses and fixes the disk D to the lower outer surface 31a, and an insertion portion 31b inserted into the coupling hole 27a protrudes from the lower center.

In the conventional spindle motor, when a current is supplied to the coil 21b of the stator 21, a rotating magnetic field is generated, and the magnet 23b, that is, the rotor (2) is caused by an electromagnetic force formed between the coil 21b and the magnet 23b. 23) rotates. As a result, the rotating shaft 19 and the turntable 27 fixed to the rotating shaft 19 also rotate together with the rotation of the disk D mounted on the turntable 27.

In this case, as shown in FIG. 1, the chucking device 30 vertically moves above the turntable 27 to suppress the rising of the disk D while rotating together with the rotor 23 and the turntable 27 during high-speed rotation.

However, the conventional spindle motor as described above fuses a plurality of bosses 28 of the turntable 27 when the yoke 29 is fixed to the turntable 27. However, the yoke 29 fixing method may cause an error in the welding process according to the diameter or length of the boss 28. That is, if the diameter of the boss 28 is larger than the through hole 29a of the yoke 29, the yoke 29 cannot be fixed to the turntable 27. If the length of the boss 28 is short, the welding is not performed properly. It does not cause fixing failure. This poor fusion causes a problem that the yoke 29 is separated from the turntable 27 when the turntable 27 rotates together with the disk D at a high speed (about 10,500 RPM).

In addition, the yoke 29, which is a metal material, acts to move toward the magnet 33 by the magnetic force of the magnet 33 of the chucking device 30 when the disk D is chucked. As a result, as the chucking process is repeated, the fatigue load increases in the welded portion of the boss 28 fixing the yoke 29, and the yoke 29 leaves the turntable 27 when the welded portion is broken. There was.

Moreover, a plurality of jaws 27c that suppress the left and right movement of the disk D should be manufactured so that the concentricity is exactly matched. However, the prior art has to form a coupling hole 27a for inserting a plurality of bosses 28 and rotational shafts 19 into the turntable 27, while forming these configurations to accurately match the concentricity of the plurality of jaws 27c. There was a very difficult problem. If the concentricity of the plurality of jaws 27c is not set correctly, an error may occur in the process of reading the disk D, and there is a problem that causes vibration and noise.

In addition, the rotation shaft 19 is bonded to the coupling hole 27a of the turntable 27. Therefore, when the bonding force between the rotary shaft 19 and the coupling hole 27c is weakened during long time use, the turntable 27 is separated from the rotary shaft 19. In addition, if the rotation shaft 19 and the turntable 27 do not form a right angle with each other when bonding the rotary shaft 19, the verticality of the rotary shaft 19 is not secured even at a minute degree, causing vibration and noise. there was.

In addition, the bearing housing 13 is formed of a metal material having a higher hardness than the center free bearing 17. As a result, when the center free bearing 17 is press-fitted into the bearing housing 13, the inside diameter of the center free bearing 17 is changed by the press-fitting, and the inside diameter of the bearing is processed by a sizing process for correcting the change. Required. Furthermore, since the center free bearing 17 is expensive, there is a problem of raising the manufacturing cost of the motor.

In addition, in the Patent Publication No. 10-2007-90583, the turntable is coupled to the rotor yoke as a medium to the rotating shaft portion immediately above the bearing, so that the centrifugal force acting point generated by the disc and the eccentric of the rotor and the upper support point of the bearing supporting the rotating shaft Because it is located as close as possible, the life of the bearing is extended as the centrifugal force generated by the eccentric rotation acts on the bearing to the minimum, and the short rotating shaft and the long bearing housing are used without changing the overall height of the spindle motor. Spindle motors have been proposed that can adopt long bearings to further extend the life of the bearings.

The Patent Publication No. 10-2007-90583 uses an expensive center pre-bearing, and there is a disadvantage in that coupling and positioning between the cylindrical bearing housing and the cylindrical coupling portion of the base plate cannot be simply performed.

Furthermore, in the conventional spindle motors shown in the above Patent Publications Nos. 10-2007-90583 and 10-2010-0043525, the coupling of the bearing housing and the base plate and the coupling of the bearing housing and the cap rotate the outer and inner projections ( It is made by spinning) or caulking process, there is a complex disadvantage of the assembly process.

In addition, conventionally, when the spinning or caulking process is performed to secure the coupling between the bearing housing, the base plate and the cap, the verticality of the bearing housing with respect to the base plate may be shifted. As a result, press-fitting the bearing into the bearing housing causes problems of bearing verticality and run-out, requiring repair. In this case, when the rotating shaft is assembled to the bearing without repair, the rotating shaft is inclined with respect to the base plate, and thus vibration and noise are generated.

In addition, in the case of poor spinning or caulking operation for coupling the cap, there is a disadvantage that the oil of the bearing leaks through the contact portion of the bearing housing and the cap.

Moreover, in the conventional spindle motor, the bearing housing uses a brass or aluminum material, and is manufactured in a CNC machine or manufactured by extrusion, which has a disadvantage of high manufacturing cost.

Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art, the object of the present invention is conventionally used by press-installing the first and second sleeve bearings for supporting the upper and lower parts of the rotating shaft in the bearing housing It is to provide a spindle motor that can reduce the cost of the product by omitting the use of the expensive center free bearing.

Another object of the present invention is to form a bearing housing with resin, so that when the first and second sleeve bearings are press-assembled into the bearing housing, the strength of the first and second sleeve bearings is greater than that of the bearing housing. The present invention provides a spindle motor in which no change occurs and no sizing process is required.

Another object of the present invention is to provide a structure of the turntable as the upper surface of the rotor yoke is provided with a protrusion having a certain area and the turntable is directly press-assembled and the chucking device by press-fitting the magnet of the chucking device to the turntable. It is to provide a spindle motor that can simplify and prevent defects due to the fixing structure of the rotor yoke.

Another object of the present invention is to set the concentricity of the jaws by omitting the yoke fixing boss and the coupling hole for inserting the rotation axis corresponding to the factors affecting the concentricity of the plurality of jaws for suppressing the horizontal movement of the disk It is to provide a spindle motor having a turntable that can be easily performed.

Still another object of the present invention is to manufacture the rotor yoke by using a metal material such as a rotating shaft and directly press-assemble the rotating shaft to the rotor yoke, thereby preventing the rotor yoke from deviating from the rotating shaft and ensuring the verticality of the rotating shaft to prevent vibration and noise generation. To provide a spindle motor that can be prevented.

In order to achieve the above object, the present invention, a disk-shaped recording medium is removable; A rotor yoke having a plurality of magnets and magnets mounted thereon, wherein the rotor yoke has a protrusion formed at a central portion of the turntable at an upper center thereof, and a rotor having a rotary shaft press-coupled to a center of the protrusion; A bearing housing made of resin and having a through hole into which the rotating shaft is inserted; And a pair of bearings disposed at intervals in the through hole of the bearing housing to rotatably support the rotating shaft. And a stator coupled to an outer diameter portion of the bearing housing so as to face the rotor and generating a magnetic field to rotationally drive the rotor when a driving signal is applied thereto.

One of the pair of bearings is press-fitted to the upper side of the through-hole of the bearing housing to support the upper portion of the rotating shaft, and the other one is press-fitted to the lower side of the through-hole of the bearing housing to support the lower portion of the rotating shaft. It is preferable. In this case, it is preferable that the pair of bearings use a sleeve bearing that is cheaper than a conventional expensive center free bearing.

The bearing housing may be coupled to the lower end of the through hole cap for supporting the lower end of the rotating shaft, in which case the cap is preferably made of a resin of the same material as the bearing housing.

The bearing housing may include a printed circuit board for driving circuits configured to extend from the lower end of the bearing housing to apply a driving signal to the stator on an upper surface thereof, and a base plate fixed to the disk drive device may be integrally formed. Can be. In this case, the base plate may be integrated by insert injection while injection molding the bearing housing, or the base plate may be integrated by heat fusion or bonding to the injection molded bearing housing.

Protruding portion of the rotor yoke is preferably a first magnet that is magnetically attracted to the chucking device disposed above the rotor is a press-fit.

A second magnet is disposed at a lower end of the protrusion of the rotor yoke, and the second magnet maintains a predetermined distance from the bearing press-fitted to the upper side of the through hole of the bearing housing, so that the rotating shaft is separated from the bearing housing. It can prevent. In this case, it is preferable to use a thrust magnet for the second magnet.

It is preferable that the rotor yoke including the projecting portion of the rotor is made of a porcelain forming material to serve as a back yoke for forming a magnetic circuit.

The turntable includes an annular body for seating and supporting a recording medium loaded on an upper surface together with the chucking device; A mounting portion protruding from the inner circumference of the annular body and having a coupling hole press-fitted to the protrusion of the rotor case at the center thereof, the mounting portion detachably coupled to the outer circumference of the recording medium; And a plurality of jaws installed on an outer circumference of the mounting portion and elastically coupled to an inner circumference of a recording medium.

As described above, in the present invention, the structure of the turntable can be simplified and slim by omitting a plurality of bosses for fixing the rotor yoke and the rotor yoke coupled to the turntable to the turntable, and the turntable is press-fitted directly into the rotor yoke. In combination there is an advantage that can fundamentally eliminate the fixing defects according to the fixing structure of the yoke.

In addition, the spindle motor of the present invention, by making the rotor yoke made of a metal material, such as the rotary shaft to press-fit the rotary shaft directly to the rotor yoke, it is possible to secure a firm holding force compared to the conventional weak bonding coupling, the vertical degree of the rotary shaft It can be secured together.

In addition, the spindle motor according to the present invention forms a bearing housing using resin and at the same time integrates the base plate by insert molding or insert injection method, thereby ensuring the verticality of the bearing and the rotating shaft assembled therewith. Likewise, by using an inexpensive sleeve bearing instead of using an expensive center free bearing, it is possible to reduce manufacturing costs and to improve the assembly process.

Furthermore, in the present invention, since the strength of the bearing is greater than that of the bearing housing when the bearing is press-fitted and assembled into the bearing housing, no change in the bearing inner diameter occurs and a sizing process is not required.

In addition, in the present invention, when forming a cap coupled to the bearing housing to support the rotating shaft, the support washer can be omitted using the same material as the support washer, thereby reducing assembly parts and improving the verticality of the rotating shaft. Vibration and noise can be reduced.

1 is a cross-sectional view showing a conventional spindle motor and a chucking device;

2 is a cross-sectional view showing a spindle motor according to an embodiment of the present invention;

3 is a perspective view illustrating the turntable and the rotor yoke illustrated in FIG. 2;

4 is a schematic view showing a state in which the disk is chucked through the spindle motor and the chucking device according to an embodiment of the present invention.

Hereinafter, the configuration of the spindle motor according to an embodiment of the present invention with reference to the accompanying drawings in detail.

First of all, the present invention can be applied not only to a spindle motor requiring high speed rotation but also to a low speed rotation motor, and also to both a DC motor or a brushless DC motor (BLDC motor). In the following description with reference to the drawings will be described by way of example the present invention is applied to a spindle motor of the BLDC type as a preferred embodiment.

First, referring to FIG. 2, the ultra-thin spindle motor 100 according to an exemplary embodiment of the present invention includes a stator (or armature) 140 and an outer rotor type rotor 180. do.

First, the stator 140 is formed with a bobbin 142 made of an insulator for each tooth on a core 141 in which a plurality of teeth protrude radially from a ring-shaped body, and the outside of the bobbin 142. Has a structure in which a coil 143 is wound.

The rotor 180 includes a rotor yoke 181 having an inverted cup shape and a ring magnet 182 in which a plurality of N-pole and S-pole magnets are alternately arranged, or split-magnetizing the N-pole and S-pole. have.

The rotor yoke 181 uses a magnetic path forming material formed from a plurality of laminated laminations of, for example, a non-oriented electrical steel sheet as a back yoke for forming a magnetic circuit. In addition to the electrical steel sheet, all the magnetic core materials having low core loss and high permeability may be adopted.

The rotor yoke 181 is bent downward from the distal end of the cover plate 181a so as to face the outer circumferential portion of the stator 140 and the cover plate 181a having a substantially disc shape, and the magnet 182 is attached to the inner circumferential surface thereof. 1 downward bending portion 181b, an upward bending portion 181c protruding upward in the central portion of the cover plate 181a, and the coupling hole 172 of the turntable 170 described later is press-assembled, and the upward bending portion A second downward bent portion in which a horizontal portion 181d extending horizontally from the tip of 181c and a rotating shaft 150 to be described later to be stably coupled by being bent downward again from the tip of the horizontal portion 181d ( 181e).

In this case, the upwardly bent portion 181c of the rotor yoke 181 is firmly press-fitted with the coupling hole 172 of the turntable 170 and positioned above the horizontal portion 181d having a predetermined area in an annular band shape. The first magnet 128 is also press-fitted into the coupling hole 172 of the turntable 172. The first magnet 128 serves to pull the chucking device 300 made of metal toward the turntable 170 when the chucking device 300 is positioned above the turntable 170 to chuck the disk. Accordingly, a stable chucking action of the disk D is achieved through the chucking device 300.

* Through the structure of the rotor yoke 181 as described above, the spindle motor 100 of the present invention can omit the yoke structure fixed on the conventional turntable, and also a fixing defect that occurs in the compression fixing structure of the complex yoke This can solve the problem of the yoke moving away from the turntable.

Further, the second downward bent portion 181e of the rotor yoke 181 has a coupling hole 181f to which the rotation shaft 150 is coupled. As the rotor yoke 181 is made of a metal material such as the rotating shaft 150, a strong fixing force can be secured through the press-fitting coupling between the coupling hole 181f and the rotating shaft 150 instead of the conventional weak bonding force. Can be.

As the rotor yoke 181 and the rotation shaft 150 are coupled to each other through a strong compression coupling, the rotor yoke 181 may be prevented from being separated from the rotation shaft 150 during high speed rotation.

In addition, the strong pressing coupling between the rotor yoke 181 and the rotating shaft 150 of the present invention can easily ensure the vertical degree of the rotating shaft 150, compared to the conventional bonding coupling, the rotor yoke 181 and the rotating shaft ( Indentation coupling between the 150) can be made simple and fast assembly process compared to the conventional bonding bonds high assembly productivity.

On the other hand, the rotor yoke 181 is made of a magnetic material forming the second magnet 129 (for example, close to the lower end of the second downward bent portion 181e, together with the role of the back yoke for the magnet 182) (for example, The thrust magnet can be used) and the first sleeve bearing 161, which will be described later, is mutually attracted by magnetic force, thereby allowing the rotor 180 to float and flow in the axial direction during rotation of the rotor 180. prevent.

In this case, the second magnet 129 is strongly press-fitted to the rotation shaft 150 and maintains a predetermined distance from the upper surface of the first sleeve bearing 161. This interval is preferably set in consideration of the mutual suction action by the magnetic force with the first sleeve bearing 161, the rotational speed of the rotary shaft 150 and the magnetic force such that the rotary shaft 150 does not rise.

In addition, the present invention, by using a strong suction action between the second magnet 129 and the first sleeve bearing 161, it is possible to omit the stopper 14 for preventing the deviation of the rotation shaft as in the prior art, and the rotation shaft 150 The process of processing the groove for coupling the stopper 14 to one peripheral surface of the) can be omitted.

In addition, in the present invention, since the magnetic center (center) of the rotor magnet 182 has a structure located above the core 141 of the stator 140, it also serves to prevent the departure of the rotor yoke 181.

Referring to FIG. 3, the turntable 170 is a half height type, and includes an annular body 170a on which a recording medium loaded on an upper surface of the turntable 170 is mounted together with the chucking device. Protruding from the inner circumferential portion of the annular body (170a) is provided with a coupling hole 172 in which the protrusion of the rotor yoke (181), that is, the upward bent portion (181c) is press-fitted, the outer peripheral portion of the disk (D) It includes a mounting portion 171 that the inner peripheral portion is detachably coupled, and a plurality of jaws 173 installed on the outer circumference of the mounting portion and elastically coupled to the inner peripheral portion of the disk (D).

Generally, the recording medium, i.e., the disc D, has an opening in the center, and data is recorded on one or both surfaces.

In addition, the turntable 170 is made of a rubber ring to prevent the slit of the disk (D) on the outside to secure the disk (D), that is, the recording medium is stored on the outer upper surface of the annular body (170a) The disc support part 175 is arrange | positioned.

The turntable 170 has a mounting portion 171 protruding from and detached from the disk D in the center of the annular body 170a, and a plurality of jaws 173 are elastically formed on the outer circumference of the mounting portion 171 at equal intervals. . In this case, the plurality of jaws 173 are elastically coupled to the inner diameter portion of the disk D to prevent the disk from escaping in the horizontal direction.

The mounting portion 171 is formed with a coupling hole 172, the center of which is press-fitted to the upward bent portion 181c of the rotor yoke 181. Therefore, the turntable 170 does not need to form a coupling hole to which a separate boss and a rotating shaft are coupled to fix the yoke as in the related art. Accordingly, it is easy to match the concentricity of the plurality of jaws 173 by omitting the bosses and the coupling holes that interfere with the adjustment of the concentricity of the plurality of jaws 173 formed on the turntable 170.

As such, the turntable 170 may have a simple structure by omitting a structure such as a yoke, a boss, and a coupling hole. Accordingly, the mold design of the turntable may be easy, and the thickness of the yoke and the boss may be maintained. Since the height of the turntable 170 as a whole can be lowered, a more slim structure can be realized.

When the current is supplied to the coil 143, the spindle motor 100 configured as described above generates a rotating magnetic field, and the magnet 182, that is, the rotor 180 is caused by an electromagnetic force formed between the coil 143 and the magnet 182. Rotation of the disk D mounted on the rotor yoke 181 is performed while the rotation of the.

On the other hand, the bearing housing 120 of the spindle motor 100 of the present invention is the stator 140 is coupled to the upper outer peripheral portion, the base plate (or bracket) 110 is formed integrally coupled to the lower outer peripheral portion, the rotating shaft ( The through hole 121 is formed at the center of the through hole 150.

In this case, a first coupling groove 121a through which the first sleeve bearing 161 is press-fitted is formed above the inner circumferential portion of the through hole 121, and a second coupling groove 121b formed below the inner circumference portion is formed in the second coupling groove 121b. The sleeve bearing 162 and the cap 124 are press fit. Accordingly, the rotor 180 is rotatably supported by the first and

second sleeve bearings

161 and 162 disposed at a sufficient distance from the rotating shaft 150 coupled to the center thereof.

The bearing housing 120 may be manufactured by injection molding using a thermosetting resin or a thermoplastic resin, such as an engineering plastic material such as nylon 66 or polycarbonate (PC).

In addition, the cap 124 is formed of a material such as nylon 66 or engineering plastics such as polycarbonate (PC), which is used as a material for the conventional support washer, thereby reducing frictional resistance with the lower end of the conventional rotation shaft 150. It is possible to omit the support washers used to reduce them. In this case, any material used for injection molding can be used as long as it is a plastic material having a hardness that is equal to or higher than that of a material conventionally used for support washers, and which has injection moldability. As such, in the present invention, as the cap 120 serves as a support washer, it is possible to reduce the number of parts by omitting the support washer that has been used in the past.

In addition, the cap 124 may adopt a bonding coupling method in addition to the press-fit coupling method in the second coupling groove 121b, and in any manner, seals the foreign material into the through-hole 121 of the bearing housing 120 so that foreign matter does not flow in and out. It is desirable to secure the sex.

The base plate 110 fixedly supports the bearing housing 120 and the stator 140 as a whole, and may be manufactured in various shapes to be fixedly installed to various disk drive devices in which the spindle motor 100 is installed. Can be.

In addition, the base plate 110 is preferably made of a lightweight material such as aluminum or an aluminum alloy or an iron-based alloy, but may be made of another metal material or synthetic resin. In this case, the base plate 110 may be integrated with the bearing housing 120 by insert injection or insert molding at the time of manufacturing the bearing housing 120 that is injection molded using thermoplastic or thermosetting resin. have.

In addition, in the present invention, the bearing housing 120 and the base plate 110 may of course be integrated using the same resin.

The bearing housing 120 is a part of the inner portion of the base plate 110 in the first outer diameter portion 125 of the outer peripheral portion is embedded in the injection molding method during the injection molding of the bearing housing 120, the bearing housing 120 ) Is integrated.

It describes the assembly method of the spindle motor 100 according to an embodiment of the present invention configured as described above.

First, the bearing housing 120 is molded by an insert injection method, and at the same time, the inner part of the base plate 110 is molded to be embedded to integrate the bearing housing 120 and the base plate 110.

Subsequently, a printed circuit board (PCB) 137 that applies a driving signal to the stator 140 to the base plate 110 disposed below the stator 140 is fixed by caulking or the like.

Thereafter, the second sleeve bearing 162 and the cap 124 are sequentially inserted into the second coupling groove 121b formed at the lower end of the inner circumference of the through hole 121 of the bearing housing 120. When the second sleeve bearing 162 is inserted and fixed to the second coupling groove 121b, the second sleeve bearing 162 may be fixed by a method such as fixing or fusion using an adhesive in addition to the press fitting.

Subsequently, the first sleeve bearing 161 is inserted into the first coupling groove 121a formed at the upper end of the inner circumference of the through hole 121 of the bearing housing 120. In this case, like the second sleeve bearing 162, the first sleeve bearing 161 may be fixed by a method such as fixing or fusion using an adhesive in addition to the press fitting when the first coupling groove 121a is inserted and fixed. have.

Subsequently, the stator 140, which is assembled in advance, is placed on the outer circumference of the third outer diameter portion 127 so as to rest on the stepped portion between the second outer diameter portion 126 and the third outer diameter portion 127 of the bearing housing 120. After press fit, it is fixed with an adhesive.

Subsequently, after press-fitting to the upward bending portion 181c of the rotor yoke 181 from the downward direction to the coupling hole 172 of the turntable 170, and pressing-fitting the first magnets 128 from the upward direction, respectively, When one end of the rotating shaft 150 is press-fitted to the engaging hole 181f of the yoke 181, the rotating body is completed. In this case, the second magnet 129, which is a ring thrust magnet, is bonded to the lower end of the second downward bent portion 181e of the rotor yoke 181 in advance.

Subsequently, the other end of the rotation shaft 150 is inserted into the hollow parts of the first and

second sleeve bearings

161 and 162, and the lower end is coupled until it contacts the bottom surface of the recess 124a of the cap 124, thereby completing the assembly.

Referring to FIG. 4, the spindle motor 100 assembled as described above raises the disk D mounted on the turntable 170 together with the chucking device 300 that moves in the vertical direction from the spindle motor 100 during operation. To prevent. In this case, the chucking device 300 does not have a magnet inside, unlike the related art.

As described above, the spindle motor 100 according to the embodiment of the present invention may turn the chucking device 300 through the first magnet 128 that is press-fitted to the coupling hole 172 of the turntable 170. By pulling toward the side 170, the chucking device 300 can stably chuck the disk (D). Accordingly, it is not necessary to provide a separate magnet in the chucking device 300 so that the structure of the chucking device can be simply formed, and the yoke fixedly coupled to the conventional turntable can be omitted, thereby simplifying the complicated structure of the conventional turntable. Can be. Accordingly, the concentricity of the plurality of jaws 173 formed on the turntable 170 can be set more easily, and the mold design of the turntable 170 can be facilitated.

That is, since the first magnet 128 is directly press-coupled to the turntable 170, it is possible to omit the yoke separately provided in the conventional turntable, thereby fundamentally preventing the complicated work of fixing the yoke and the yoke from the turntable. have.

Furthermore, the rotor yoke 181 is separated from the rotation shaft 150 by being firmly coupled to each other by press-fitting the rotation shaft 150 made of metal into the coupling hole 181f of the rotor yoke 181 made of the same metal. Deviation can be prevented and assembly productivity can be increased.

In addition, by forming a bearing housing 120 using a resin and at the same time, a part of the base plate 110 is integrated by insert molding or insert injection method, thereby improving the verticality of the bearing 160 and the rotating shaft 150 assembled therewith. We can secure enough.

In addition, in the present invention, the cap 120 may be formed of the same material as that of the support washer to reduce assembly parts, and the vibration and noise may be reduced by improving the verticality of the rotation shaft 150.

Furthermore, in the present invention, when the first and

second sleeve bearings

161 and 162 are press-fitted to the bearing housing 120, the strengths of the first and

second sleeve bearings

161 and 162 made of metal are made of resin. Since the inner diameters of the first and

second sleeve bearings

161 and 162 are not changed since they are larger than the strength of the sizing, the sizing process is not required.

In addition, the cost competitiveness of the product can be secured by lowering the manufacturing cost by using the

sleeve bearings

161 and 162 that are less expensive than the conventional center free bearings.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto, and the technical idea of the present invention and the following by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims to be described.

The present invention relates to a technology that can reduce the unit cost of the product by eliminating the expensive center-free bearing, to ensure the verticality of the bearing and the rotating shaft, and also to implement a simple structure of the turntable, it is applied to the spindle motor.

Claims

A turntable to which the disk-shaped recording medium is attached and detached;

A rotor yoke having a plurality of magnets mounted thereon, the rotor yoke having a protrusion formed at a central portion of the turntable at an upper center thereof, and a rotor having a rotation shaft press-coupled to a center of the protrusion;

A bearing housing made of resin and having a through hole into which the rotating shaft is inserted;

A pair of bearings disposed at intervals in the through hole of the bearing housing to rotatably support the rotating shaft; And

And a stator coupled to an outer diameter portion of the bearing housing so as to face a magnet of the rotor and generating an electromagnetic field to rotationally drive the rotor when a driving signal is applied.
The through hole of the bearing housing of claim 1, wherein one of the pair of bearings is press-fitted to an upper side of the through hole of the bearing housing to support an upper portion of the rotating shaft, and the other one of the bearings to support a lower portion of the rotating shaft. Spindle motor, characterized in that the press-fit coupled to the lower side.
The spindle motor of claim 1, wherein the pair of bearings are sleeve bearings.
The spindle motor of claim 1, wherein a cap for supporting one bearing is coupled to a lower end of the through shaft of the bearing housing.
The method of claim 1, wherein the turntable

An annular body for seating and supporting a recording medium loaded on an upper surface together with the chucking device;

A mounting portion protruding from the inner circumference of the annular body and having a coupling hole press-fitted to the protrusion of the rotor case at the center thereof, the mounting portion detachably coupled to the outer circumference of the recording medium; And

And a plurality of jaws installed on an outer circumference of the mounting portion and elastically coupled to an inner circumference of a recording medium.
The base of claim 1, wherein the bearing housing has a printed circuit board for driving circuits on which an outer circumferential portion extends from a lower end of the bearing housing to apply a driving signal to the stator on an upper surface thereof, and is fixed to a disk drive device. Spindle motor, characterized in that the plate is formed integrally.
The motor according to claim 6, wherein the base plate is integrated by insert injection while injection molding the bearing housing, or the base plate is integrated by heat fusion or bonding into an injection molded bearing housing.
The spindle motor of claim 1, wherein the protrusion of the rotor yoke is press-coupled to a chucking device disposed above the rotor and having a magnetic first suction magnet.
3. The bearing of claim 2, wherein a second magnet is disposed at a lower end of the protruding portion of the rotor yoke, and the second magnet is press-fitted to an upper side of a through hole of a bearing housing so as to suppress an increase during rotation of the rotor. Spindle motor, characterized in that to maintain the spacing.
The rotor yoke of claim 1, wherein the rotor yoke is

A cover plate made of a disc shape;

A first downward bent portion that is bent downward from the distal end of the cover plate so as to face the outer peripheral portion of the stator, and the magnet is attached to the inner peripheral surface thereof;

An upward bent portion protruding upward from a central portion of the cover plate to press-assemble the coupling hole of the turntable;

A horizontal portion extending horizontally from the tip of the upward bent portion; And

And a second downward bent portion which is bent downwardly from the front end of the horizontal portion to stably couple the rotating shaft.