KR100446450B1 - Spindle motor for hard disk drive having insulation and protection against heat structure - Google Patents

Abstract

The present invention forms irregularities at equal intervals on the inner circumferential surface of the stator indentation hole or the outer circumferential surface of the base so that the contact area between the inner circumferential surface of the stator and the outer circumferential surface of the stator can be significantly reduced, as well as the inner circumferential surface and the stator of the stator. Improved thermal stability of the bearing by preventing heat generated from the stator from being transferred to the ball bearing and dynamic bearing through the base by improving the thermal insulation property in the radial direction through the voids formed between the outer circumferential surfaces of the The purpose is to prevent heat from reaching the platters and thereby preventing thermal deformation of the platters. The present invention configured for this purpose is to form irregularities on any one of the inner circumferential surface of the stator indentation hole and the outer circumferential surface of the stator inserted into the indentation hole of the stator to press-fit and couple the indentation hole of the stator to the fixed body and the outer circumference of the stator. A large number of voids are formed between the inner circumferential surfaces of the indentation hole, which significantly reduces the contact area between the inner circumferential surface of the stator and the outer circumferential surface of the stator, as well as the voids formed between the inner circumferential surface of the stator and the outer circumferential surface of the stator. By improving the thermal insulation properties in the radial direction, the heat generated from the stator is not transmitted to the ball bearings and dynamic bearings through the base, thereby improving the thermal stability of the bearings, and also preventing the heat generated from the stator from reaching the platters. It is to prevent heat deformation.

Description

Spindle motor for hard disk drive having insulation and protection against heat structure

The present invention relates to a spindle motor for a hard disk drive, and more particularly, to insulate the inner circumferential surface of the stator or to the outer circumferential surface of the fixture for fixing the stator at equal intervals or to form a plurality of heat dissipation fins on the lower surface of the base to insulate and Insulation and heat dissipation structure prevents heat generated from the stator from being transmitted to the ball bearing and dynamic bearing through the base, and prevents heat deformation of the platter by preventing heat generated from the stator from reaching the platter by improving heat dissipation characteristics. It relates to a spindle motor for a hard disk drive having a.

In general, a hard disk drive is a secondary storage device of a computer. The hard disk drive includes a platter, a head, a spindle motor, a head arm, and a circuit board to read information stored in the platter through the head. By reproducing or recording new information on the platter, it contributes to the computer's system operation.

In the above configuration of the hard disk drive, the platter writes data here with a magnetic disk coated metal. These platters are rotated by inserting them into several shafts, which are the spindle shafts, and the motors that turn the platters are the spindle motors.

The head that reads and writes data to the platter is connected to the head arm, and moves the head arm to move the head to the desired address. This head arm is also called an actuator and it is the voice coilmotor (VCM) that drives it. The following is a description of the spindle motor according to the prior art.

Figure 1 is an exploded perspective view showing a spindle motor for a hard disk of the ball bearing application structure according to the prior art, Figure 2 is a longitudinal cross-sectional view of FIG.

As shown in FIGS. 1 and 2, the spindle motor 10 for a hard disk of a conventional ball bearing structure has a base 11 and a base having a lower portion formed by protruding and forming a fixed body 11a having a concentric shape on an upper surface thereof. 11, the spindle shaft 12 is installed in the vertical direction in the center of the center, the lower ball bearing 13 is installed on the outer periphery of the spindle shaft 12 on the upper side of the base 11, the press-in hole (14a) is formed in the center On the other hand, the stator 14 is formed radially on the outer circumferential surface and formed of a core 14b on which the coil 14c is wound, press-fitted and fixed to the outer circumferential surface of the fixing body 11a of the base 11 through the press-in hole 14a, The hub 16 which is rotatably supported by the outer periphery of the upper and lower ball bearings 13 and 15 in a structure covering the upper ball bearing 15 and the upper part of the base 11 installed on the upper portion of the spindle shaft 12. , The hub 16 is provided on the inner peripheral surface of the lower side of the hub 16 through a magnetic field formed between the coil 14c and the hub 16c. It consists of a permanent magnet 17 in the form of a ring to generate a driving force to rotate.

The spindle motor 10 for a hard disk of the conventional ball bearing structure configured as described above has a magnetic field (not shown) between the core 14b and the permanent magnet 17 when power is applied to the coil 14c of the stator 14. ) Is formed. By the magnetic field between the core 14b and the permanent magnet 17, the hub 16 is rotated in one direction.

However, as described above, in the process of rotating the hub, a lot of heat is generated in the stator. Accordingly, the heat is transferred to the base through the fixture of the base which is in surface contact with the inner circumferential surface of the indentation hole, and thus a lot of heat is transferred to the lower ball bearing. The lower ball bearing is deteriorated in thermal stability, and heat generated in the stator is transferred to the platter, causing a problem of thermal deformation of the platter.

Therefore, the spindle motor for a hard disk of the conventional ball bearing structure as described above has no thermal insulation structure that prevents heat generated from the stator from being transferred to the lower ball bearing, so that thermal stability is lowered and rotational accuracy is lowered. The rotational accuracy of other precision parts is reduced. 3 shows a dynamic bearing structure.

3 is a longitudinal sectional view showing a spindle motor for a hard disk of a dynamic bearing application structure according to the prior art.

As shown in FIG. 3, the spindle motor 20 for a hard disk having an aerodynamic bearing application structure according to the prior art has a base 21 having a concentric circular body 21a formed on an upper surface thereof to form a lower portion 21. ), A lower bearing 22 installed at the center upper side of the base 21, a press-fitting hole 23a is formed in the center portion, and a plurality of radially formed on the outer circumferential surface of the core 23b to which the coil 23c is wound. The stator 23 is press-fitted and fixed to the outer circumferential surface of the fixing body 21a of the base 21 through the press-in hole 23a, the spindle shaft 24 installed vertically in the upper center of the lower bearing 22, the spindle shaft. The upper bearing 25 installed on the upper portion of the 24, the hub 26, which is rotatably supported on the outside of the spindle shaft 24 in a structure covering the upper portion of the base 21, the inner upper portion of the hub 26 Installed to form dynamic pressure for smooth rotation of hub (26) around spindle axis (24) It is installed on the inner circumferential surface of the lower first and second dynamic bearings 27, the second dynamic pressure bearing 28, and the lower side of the hub 26 to form a magnetic field between the coil 23c and the driving force to rotate the hub 26. It consists of a permanent magnet 29 to generate.

In the hard disk spindle motor 20 of the dynamic pressure bearing application structure configured as described above, when power is applied to the coil 23c, a magnetic field is formed between the core 23b and the permanent magnet 29, and the core 23b And the hub 26 rotates in one direction by the magnetic field between the permanent magnet 29 and the permanent magnet 29.

On the other hand, when the hub 26 rotates, air flows on the inner surfaces of the first and second dynamic pressure bearings 27 and 28, and as the rotation of the hub 26 increases, the first and second dynamic pressure bearings ( Between the 27 and 28 and the spindle shaft 24, the upper bearing 25, and the lower bearing 22, a larger rigid air layer is formed in proportion to the rotational speed of the hub 26. Accordingly, the hub 26 mounted with a platter (not shown) has the spindle shaft 24 overcoming the load and disturbance imposed by bearing the air layer having a predetermined rigidity formed between the spindle shaft 24 as a bearing. Rotate around the center

However, since most of the loss heat generated in the spindle motor for a hard disk of the conventional dynamic pressure bearing application as described above is generated in the stator and is directly conducted to the base side, the temperature difference of the air layer becomes large according to the load, and the thickness of the air layer becomes severe. Due to the change in the thickness of the air layer according to the temperature difference occurs a problem that the rotational accuracy of the bearing is lowered.

The present invention was devised to solve the above-mentioned problems, and formed irregularities at equal intervals on the inner circumferential surface of the presser hole of the stator or the outer circumferential surface of the base, thereby remarkably reducing the contact area between the inner circumferential surface of the stator and the outer circumferential surface of the stator. In addition to reducing heat, the thermal insulation property in the radial direction is improved through the gap formed between the inner circumferential surface of the stator and the outer circumferential surface of the stator so that heat generated in the stator is not transmitted to the ball bearings and the dynamic bearing through the base. It is an object of the present invention to provide a spindle motor for a hard disk drive having an insulating structure to increase the thermal stability of the bearing.

In addition, the present invention is to improve the rotational precision by preventing the heat generated in the stator is transferred to the ball bearing and the dynamic pressure bearing through the base to increase the thermal stability of the bearing.

On the other hand, the present invention in addition to the configuration to improve the thermal insulation characteristics through the gap by forming irregularities on the inner circumferential surface of the indentation hole of the stator or the outer circumferential surface of the fixing body at equal intervals to form a plurality of heat dissipation fins on the lower surface of the base to reduce the heat dissipation area of the base The larger the heat radiation effect is to improve.

Furthermore, the present invention is to improve the structural stability of the spindle motor through the above-mentioned objects, as well as to improve the stability of the system by preventing damage to the system by heat.

1 is an exploded perspective view showing a spindle motor for a hard disk of the ball bearing application structure according to the prior art.

2 is a longitudinal sectional view of FIG. 1;

Figure 3 is a longitudinal sectional view showing a spindle motor for a hard disk of the hydrodynamic bearing application structure according to the prior art.

Figure 4 is an exploded perspective view of a ball bearing structure showing a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to the present invention.

FIG. 5 is a cross sectional view according to FIG. 4; FIG.

Figure 6 is an exploded perspective view of a ball bearing structure showing another embodiment of a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to the present invention.

7 is a cross sectional view according to FIG. 6.

8 is a cross-sectional view of a dynamic pressure bearing structure showing a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to the present invention.

9 is a cross-sectional view of a dynamic pressure bearing structure showing another embodiment of a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to the present invention.

** Description of symbols for the main parts of the drawing **

100, 200. Spindle Motor

110, 210.Base

112, 212.

114, 148, 214, 238. Unevenness

114a, 148a, 214a, 238a. air gap

120, 260.Hub

130, 150 ball bearings

140, 230. Stator

142, 232. Indentation

144, 234.Core

146, 236. Coil

170, 290. Permanent magnet

180, 216. Heat sink fins

270, 280. Dynamic Bearings

The present invention configured to achieve the above object is as follows. That is, the heat insulation structure of the spindle motor for a hard disk drive according to the present invention is a hub, the hub is a permanent body is installed on the inner circumferential surface of the base while the base is formed in the bottom, the platter is fixed to the upper portion is formed in the center of the upper surface Bearings rotatably supported on the upper part of the base and cores coiled around the outer circumferential surface are radially formed, while indentations are formed through the upper and lower indentation holes through the upper and lower parts of the base to press-fit and secure the outer circumferential surface of the fixture formed on the upper surface of the base. In a spindle motor for a hard disk drive having a stator configured to rotate a hub in one direction through a magnetic field formed between a coil and a permanent magnet when power is applied to the stator, the spindle motor is inserted into the inner circumferential surface of the stator and the press-in hole of the stator. Unevenness is formed on any one of the outer circumferential surfaces of the fixture, When the press-fit hole of the eater is press-fitted and coupled, a large number of voids are formed between the outer circumferential surface of the fixture and the inner circumferential face of the stator.

Through the above-described configuration, the present invention can significantly reduce the contact area between the inner circumferential surface of the stator and the outer circumferential surface of the stator, as well as radially through the air gap formed between the inner circumferential surface of the stator and the outer circumferential surface of the stator. By improving the thermal insulation properties of the stator, the heat generated from the stator is prevented from being transferred to the ball bearings and dynamic bearings through the base, thereby improving the thermal stability of the bearings.

The irregularities as described above may be formed on the outer circumferential surface of the fixing body so that the voids may be formed on the outer circumferential surface of the fixing body when the press-fitting / joining holes of the stator are pressed into the fixing body.

In addition, the above-mentioned concavities and convexities may be formed on the inner circumferential surface of the press-in hole of the stator so that the voids may be formed on the inner circumferential surface of the press-in hole of the stator when press-fitting and joining the press-in hole of the stator to the fixture.

On the other hand, the present invention in addition to the configuration as described above may be further configured to form a plurality of heat radiation fins on the lower surface of the base to radiate heat transferred from the stator to the base to the outside through the heat radiation fins.

Hereinafter, a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to a preferred embodiment of the present invention will be described in detail.

4 is an exploded perspective view of a ball bearing structure showing a spindle motor for a hard disk drive having a heat insulation and heat dissipation structure according to the present invention, FIG. 5 is a sectional view of FIG. 4, and FIG. 6 is a heat insulation and heat dissipation structure according to the present invention. 7 is an exploded perspective view of a ball bearing structure showing another embodiment of a spindle motor for a hard disk drive having, FIG.

First, a spindle motor for a hard disk drive having a ball bearing structure will be described as an example. As shown in FIGS. 4 to 7, the spindle motor 100 for a hard disk drive having a heat insulation and heat dissipation structure according to the present invention has a fixing body 112 protruding in the form of concentric circles on the upper surface of the base 110. Irregularities of equal intervals in any one of the inner circumferential surface of the indentation hole 142 of the stator 140, which is press-fitted to the outer circumferential surface of the stator 140 and press-coupled to the outer circumferential surface of the fixing body 112 to form a magnetic field between the permanent magnet 170 when the power is applied. (凹凸; 114 or 148 to form a pressurizing hole 142 of the stator 140 to the fixed body 112, the air between the fixed body 112 and the press-in hole 142 of the stator 140 when pressing It is configured such that a plurality of voids 114a or 148a through which is flowed can be formed.

That is, the spindle motor 100 for a hard disk drive according to the present invention forms the indentation hole 114 or 148 in any one of the inner circumferential surface of the indentation hole 142 of the stator 140 and the outer circumferential surface of the fixing body 112. (142) It is possible to significantly reduce the contact area between the inner circumferential surface and the outer circumferential surface of the fixing body 112, as well as the voids 114a or 148a formed between the inner circumferential surface of the indentation hole 142 and the outer circumferential surface of the fixing body 112. By improving the thermal insulation property in the radial direction through the heat generated in the stator 140 is not transmitted to the ball bearings (130, 150) through the base 110 to increase the thermal stability of the bearings (130, 150) It would be.

As described above, irregularities 114 or 148 of equal intervals are formed on any one of the outer circumferential surface of the fixing body 112 and the inner circumferential surface of the press-fitting hole 142 of the stator 140 to form the stator 140 on the fixing body 112. A plurality of voids by forming a plurality of voids 114a or 148a through which air can flow between the fixed body 112 and the indentation hole 142 of the stator 140 when the press-in hole 142 of the) 114a or 148a improves thermal insulation properties in the radial direction. Accordingly, the heat generated from the stator 140 is not transmitted to the ball bearings 130 and 150 by the rotation of the hub 160, thereby improving the thermal stability of the bearings 130 and 150.

On the other hand, in the lower surface of the base 110 in the spindle motor 100 for a hard disk drive according to the present invention having the insulation structure as described above, a plurality of heat radiation fins 180 are further formed from the stator 140 to the base 110. A configuration is further added to radiate heat transferred to the outside through the heat dissipation fin 180.

The spindle motor 100 for a hard disk drive to which the heat-insulating and heat-dissipating structure of the ball bearing structure according to the present invention is applied also has a base having a lower portion formed by protruding and forming a concentric body 112 in the upper surface as in the prior art. 110), the spindle shaft 120 is installed in the vertical direction in the center of the base 110, the lower ball bearing 130 is installed on the outer periphery of the spindle shaft 120 on the upper side of the base 110, the press-in hole in the center 142 is formed and a plurality of radially formed on the outer circumferential surface is made of a core 144 wound around the coil 146 is press-fitted and fixed to the outer peripheral surface of the fixture 110 of the base 110 through the indentation hole 142 Stator 140, the upper ball bearing 150 installed on the upper portion of the spindle shaft 120, the structure covering the upper portion of the base 110 is supported rotatably by the outer periphery of the upper and lower ball bearings (130, 150) Hub 160 is installed on the inner peripheral surface of the lower side of the hub 160 It is composed of a coil (146) ring-shaped permanent magnet 170 through the magnetic field formed between the driving force that generates the hub 160 rotates with.

However, in the present invention, as shown in FIGS. 4 and 5, irregularities 114 are formed at equal intervals on the outer circumferential surface of the fixing body 112 protruding and formed in the form of concentric circles on the upper surface of the base 110, and thus the stator 140 is formed. 6 to 7 or a configuration in which a gap 114a is formed between the outer circumferential surface of the fixing body 112 and the inner circumferential surface of the pressing hole 142 when press-fitted and coupled to the fixed body 112 through the press-in hole 142 or FIGS. As shown in FIG. 3, irregularities 148 are formed at equal intervals on the inner circumferential surface of the press-in hole 142 of the stator 140, and the stator 140 is press-fitted and coupled to the outer circumferential surface of the fixing body 112 through the press-in hole 142. The configuration in which the voids 148a are formed between the clamping body 112 and the inner circumferential surface of the press-in hole 142 is different.

When the power is applied to the spindle motor 100 for a hard disk drive of the present invention configured as described above, a magnetic field is formed between the core 144 and the permanent magnet 170 wound around the coil 146 of the stator 140. Accordingly, the hub 160 rotates in one direction with the spindle axis 120 as the rotation center.

As described above, a lot of heat is generated in the stator 140 in the process of rotating the hub 160 by application of power, and as such, the heat generated in the stator 140 is as shown in FIGS. 4 to 7. As in the spindle motor 100 for a hard disk drive having a heat insulating structure, the contact between the outer circumferential surface of the fixing body 112 of the upper surface of the base 110 and the inner circumferential surface of the press-in hole 142 of the stator 140 is uneven (요; Since only the iron portion of 114 or 148 is formed, the contact area is significantly reduced, so that the amount of heat transferred from the stator 140 to the fixed body 112 portion is not large. Therefore, the amount of heat generated by the stator 140 is transferred to the ball bearings 130 and 150, thereby significantly reducing the amount of thermal stability of the ball bearings 130 and 150.

In addition, as in the spindle motor 100 for a hard disk drive having an insulating structure as shown in FIGS. 4 to 7, the indentation of the stator 140 and the outer circumferential surface of the fixing body 112 of the upper surface of the base 110 are press-fitted. The contact of the inner circumferential surface of the ball 142 is made only in the iron portion of the unevenness 114 or 148, so that the unevenness portion of the unevenness 114 or 148 may allow air to flow up and down. Since heat formed in the stator 140 is formed by the air gap 114a or 148a, the transfer to the portion of the fixture 112 is blocked by the plurality of air gaps 114a or 148a. That is, the plurality of air gaps 114a or 148a described above improve thermal insulation characteristics in the radial direction so that heat generated from the stator 140 is transferred to the ball bearings 130 and 150 through the fixing body 112 and the base 110. Do not forward.

Therefore, as described above, the heat-insulating property in the radial direction is improved through the air gaps 114a or 148a so that the heat generated in the stator 140 is transferred to the ball bearings 130 and 150 through the fixing body 112 and the base 110. By not being transmitted to), it is possible to improve the thermal stability of the ball bearings 130 and 150 to improve the rotational accuracy of the spindle motor 100.

Meanwhile, the heat dissipation fins 180 formed on the bottom surface of the base 110 may maximize the heat dissipation area of the base 110 to increase the heat dissipation rate of the heat generated from the stator 140 by the application of power and transferred to the base 110. Do that fast.

The spindle motor 100 for a hard disk drive having a heat insulation and heat dissipation structure according to the present invention will be described in detail as follows. First, as shown in FIGS. 4 and 5, the base (not shown) is formed on the outer circumferential surface of the fixing body 112 protruding upward in the form of concentric circles on the upper surface of the base 110. Spindle motor 100 having a structure in which a plurality of heat dissipation fins 180 are formed on the lower surface of the 110 has an indentation hole 142 of the stator 140 on the outer circumferential surface of the fixing body 112 on which the unevenness is formed. Only the iron portion of the unevenness 114 formed on the outer circumferential surface of the fixing body 112 comes into contact with the inner circumferential surface of the press-in hole 142 of the stator 140 at the time of press-fitting and joining. The concave and convex portions of the concave and convex 114 formed on the outer circumferential surface thereof are formed of voids 114a through which air can flow up and down.

The air gap 114a formed as described above improves the thermal insulation property in the radial direction to block heat generated from the stator 140 from being transferred to the fixing body 112. As such, the heat generated from the stator 140 is not transferred to the fixture 112, so that heat transfer from the stator 140 to the ball bearings 130 and 150 through the fixture 112 and the base 110 is also performed. The thermal stability of the ball bearings 130 and 150 is formed. Therefore, the rotational accuracy of the spindle motor 100 can be improved.

Meanwhile, as shown in FIGS. 6 and 7, which is another embodiment of the ball bearing structure according to the present invention, the lower portion of the base 110 has a structure in which the unevenness 148 is formed on the inner circumferential surface of the press-in hole 142 of the stator 140. The spindle motor 100 having a structure in which a plurality of heat dissipation fins 180 are formed on the surface of the spindle motor 100 may press-fit and couple the press-in hole 142 of the stator 140 having the irregularities 148 formed on the outer circumferential surface of the fixing body 112. Only the iron portion of the concave-convex 148 formed on the inner circumferential surface of the press-in hole 142 of the stator 140 contacts the outer circumferential surface of the fixing body 112, and thus the press-in hole 142 of the stator 140. The concave and convex portions 148 formed on the inner circumferential surface are formed of voids 148a through which air can flow up and down.

The air gap 148a formed as described above improves the thermal insulation property in the radial direction to block heat generated from the stator 140 from being transferred to the fixing body 112. As such, the heat generated from the stator 140 is not transferred to the fixture 112, so that heat transfer from the stator 140 to the ball bearings 130 and 150 through the fixture 112 and the base 110 is also performed. The thermal stability of the ball bearings 130 and 150 is improved. Therefore, the rotational accuracy of the spindle motor 100 can be improved.

8 is a cross sectional view of a dynamic pressure bearing structure showing a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to the present invention, and FIG. 9 is another embodiment of a spindle motor for a hard disk drive having a heat insulating and heat dissipating structure according to the present invention. It is the sectional view of the coupling of the dynamic bearing structure which showed the example.

8 and 9 illustrate a spindle motor 200 for a hard disk drive having a hydrodynamic bearing structure. As shown in the drawing, the spindle motor 200 of the hydrodynamic bearings 270 and 280 also has an upper surface of the base 210. Concave and convex (214; 238) is formed on any one of the outer circumferential surface of the fixing body 212 protruded and formed in the form of concentricity and the inner circumferential surface of the press-in hole (see Fig. 4) of the stator 230, the fixing body 212 On the outer circumferential surface of the stator 230, a pore 214a or 238a through which the air flows may be formed when the stator 230 is press-fitted or combined. That is, as described above, the heat generated in the stator 230 is improved by improving the thermal insulation property in the radial direction through the voids 214a or 238a formed between the outer circumferential surface of the fixture 212 and the inner circumferential surface of the press-in hole of the stator 230. By not being transmitted to the dynamic bearings 270 and 280 through the fixture 212 and the base 210, the thermal stability of the dynamic bearings 270 and 280 may be improved to improve the rotational accuracy of the spindle motor 200. It would be.

The spindle motor 200 for a hard disk drive to which the heat insulation and heat dissipation structure of the dynamic pressure bearing structure according to the present invention is applied also has a base 210 having a concentric circle shape 212 formed on an upper surface thereof, as in the prior art. The lower bearing 220 is installed on the center upper side of the base 210, and a press-fit hole is formed in the center, and a plurality of radially formed on the outer circumferential surface thereof, the core 234 is wound around the base 221. The stator 230 is press-fitted and fixed to the outer peripheral surface of the fixture 212 of the 210, the spindle shaft 240 is installed in the vertical direction to the upper center of the lower bearing 220, the spindle shaft 240 is installed on the top The upper bearing 250 and the upper portion of the base 210 have a structure that is rotatably supported on the outside of the spindle shaft 240, the hub 260 is installed on the inner upper portion of the hub 260 to the spindle shaft 240 Seamless of hub 260 centered The hub 260 is formed on the inner circumferential surface of the lower side of the first and second dynamic pressure bearings 270, the second dynamic pressure bearing 280, and the lower side of the hub 260, which form dynamic pressure for the former, and forms a magnetic field between the coil 236. ) Is made of a permanent magnet 290 for generating a driving force to rotate.

However, in the present invention, as shown in FIG. 8, irregularities 214 are formed at equal intervals on the outer circumferential surface of the fixing body 212 protruding and formed in the form of concentric circles on the upper surface of the base 210 to press the stator 230. When press-fitting and coupling to the fixture 212 through the configuration that the void 214a is formed between the outer peripheral surface of the fixture 212 and the inner peripheral surface of the indentation hole or as shown in Figure 9 the indentation hole of the stator 230 Unevenness is formed on the inner circumferential surface at equal intervals so that the void 238a is formed between the fixture 212 and the inner circumferential surface of the indentation hole when the stator 230 is press-fitted and coupled to the outer circumferential surface of the fixture 212 through the indentation hole. The configuration that allows it to be formed is different.

Meanwhile, as described above, the spindle motor 200 for a hard disk drive having a dynamic pressure bearing structure also has a plurality of heat dissipation fins 216 formed on a lower surface of the base 210 to transfer heat from the stator 230 to the base 210. It will function to radiate heat to the outside.

When power is applied to the spindle motor 200 for a hard disk drive of the present invention configured as described above, when power is applied to the coil 236, a magnetic field is formed between the core 234 and the permanent magnet 290. The magnetic field between the core 234 and the permanent magnet 290 is to rotate the hub 260 in one direction.

As described above, when the hub 260 rotates, air flows on the inner surfaces of the first and second dynamic pressure bearings 270 and 280, and the first and second dynamic pressures increase as the rotation of the hub 260 increases. A greater rigid air layer is formed between the bearings 270 and 280 and the spindle shaft 240, the upper bearing 250, and the lower bearing 220 in proportion to the rotational speed of the hub 260. Accordingly, the hub 260 equipped with a platter (not shown) overcomes the load and disturbance imposed by the air pressure bearings 270 and 280 having a predetermined rigidity formed between the spindle shaft 240 and the dynamic pressure bearings 270 and 280. It is rotated about the spindle axis 240.

As described above, the heat generated in the stator 230 during the rotation of the hub 260 is a radial direction of the voids 214a or 238a formed between the outer circumferential surface of the fixture 212 and the inner circumferential surface of the press-in hole of the stator 230. It is blocked by the thermal insulation characteristics of the furnace to prevent heat from being transferred to the dynamic pressure bearings 270 and 280.

In more detail, first, as shown in FIG. 8, the concave-convex 214 is formed on the outer circumferential surface of the fixing body 212 protruding upward in the form of concentric circles on the upper surface of the base 210. Spindle motor 200 having a structure in which a plurality of heat dissipation fins 216 are formed on the bottom surface of the base 210 is a press-in hole of the stator 230 on the outer circumferential surface of the fixing body 212 in which the unevenness 214 is formed (FIG. 4), only the iron portion of the unevenness 214 formed on the outer circumferential surface of the fixture 212 comes into contact with the inner circumferential surface of the press-in hole of the stator 230 when press-fitting and coupling the clamping member 212. The concave and convex portions of the concave and convex portion 214 formed on the outer circumferential surface of the c) are formed of voids 214a through which air can flow up and down.

The air gap 214a formed as described above improves the thermal insulation property in the radial direction to block heat generated from the stator 230 from being transferred to the fixture 212. As such, the heat generated from the stator 230 is not transferred to the fixture 212, so that heat transfer from the stator 230 to the dynamic pressure bearings 270 and 280 through the base 210 is not performed. The thermal stability of the dynamic pressure bearings 270 and 280 is formed. Therefore, the rotational accuracy of the spindle motor 200 can be improved.

Meanwhile, as shown in FIG. 9, which is another embodiment of the dynamic bearing structure according to the present invention, the lower surface of the base 210 is formed on the inner circumferential surface of the indentation hole (see FIG. 4) of the stator 230. The spindle motor 200 having a plurality of heat dissipation fins 216 formed therein is a stator 230 when press-fitting and coupling the press-in hole of the stator 230 in which the unevenness 238 is formed on the outer circumferential surface of the fixture 212. Only the convex portion of the concave-convex 238 formed on the inner circumferential surface of the press-fitting hole 238 contacts the outer circumferential surface of the fixing body 212, and thus the concave-convex 238 is formed on the inner circumferential surface of the press-in hole of the stator 230. The yaw portion of is formed by the voids 238a through which air can flow up and down.

The air gap 238a formed as described above improves the thermal insulation property in the radial direction to block the heat generated from the stator 230 from being transferred to the fixture 212. As such, the heat generated from the stator 230 is not transferred to the fixture 212, so that heat transfer from the stator 230 to the dynamic pressure bearings 270 and 280 through the base 210 is not performed. The thermal stability of the dynamic pressure bearings 270 and 280 is improved. Therefore, the rotational accuracy of the spindle motor 200 can be improved.

As described above, according to the present invention, irregularities 114 or 148 and 214 are formed on one of the outer circumferential surfaces of the fixing bodies 112 and 212 of the bases 110 and 210 and the inner circumferential surfaces of the press-holes 142 of the stators 140 and 230. Alternatively, when the stator 140 or 230 is coupled to the outer circumferential surfaces of the fixing bodies 112 and 212 by forming 238, air is formed between the outer circumferential surface of the fixing bodies 112 and 212 and the inner circumferential surface of the press-in holes 142 of the stators 140 and 230. By forming a plurality of voids (114a or 148a, 214a or 238a) that can be flowed to improve the thermal insulation in the radial direction through the voids (114a or 148a, 214a or 238a) and the ball bearing (130, 150) It is possible to improve the thermal stability of the dynamic pressure bearings (270, 280), as well as to improve the rotational accuracy.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the technical idea of the present invention.

As described above, according to the present invention, irregularities are formed on the inner circumferential surface of the stator in the circumferential surface or the outer circumferential surface of the fixed body so that the voids are formed between the inner circumferential surface of the stator and the outer circumferential surface of the stator in the radial direction through the voids. By improving the thermal insulation properties, the heat generated from the stator is prevented from being transferred to the ball bearings and the dynamic pressure bearings through the base, thereby improving the thermal stability of the bearings.

In addition, the present invention is effective to improve the rotational accuracy by preventing the heat generated in the stator is transmitted to the ball bearing and the dynamic bearing through the base to increase the thermal stability of the bearing.

On the other hand, the present invention in addition to the configuration to improve the thermal insulation characteristics through the gap by forming irregularities on the inner circumferential surface of the indentation hole of the stator or the outer circumferential surface of the fixing body at equal intervals to form a plurality of heat dissipation fins on the lower surface of the base to reduce the heat dissipation area of the base It is possible to further increase the heat dissipation effect.

Furthermore, the present invention can improve the structural stability of the spindle motor through the above-described effects, as well as the effect of preventing the damage of the system due to the thermal deformation of each component to improve the stability of the system.

Claims (4)

A base having a fixed body formed at the center of the upper surface, the base having a lower portion, and a platter fixed at the upper portion, a hub having a permanent magnet installed at the inner circumferential surface of the lower portion, a bearing supporting the hub rotatably on the upper portion of the base, and a coil at an outer circumferential surface thereof. The winding is made of a stator that is formed in the center of the radially while the press-hole is formed through the top and bottom in the center of the base and press-fitted and fixed to the outer peripheral surface of the fixed body formed on the upper surface of the base when the power is applied to the stator and In the spindle motor for a hard disk drive of the structure to rotate the hub in one direction through a magnetic field formed between the permanent magnet, Unevenness is formed in any one of an inner circumferential surface of the press-fitting hole of the stator and an outer circumferential surface of the fixture inserted into the press-fitting hole of the stator to press-fit the outer circumferential surface of the fixture and the stator when press-fitting and coupling the press-fitting hole of the stator to the fixture. Spindle motor for a hard disk drive having an insulating structure characterized in that a plurality of voids are formed between the inner peripheral surface of the ball. The spindle motor of claim 1, wherein the unevenness is formed on an outer circumferential surface of the fixture. The spindle motor of claim 1, wherein the unevenness is formed on an inner circumferential surface of a press-in hole of the stator. The heat sink according to any one of claims 1 to 3, further comprising a plurality of heat dissipation fins formed on the lower surface of the base to dissipate heat transferred from the stator to the base to the outside through the heat dissipation fins. Spindle motor for hard disk drive with heat insulation and heat dissipation structure.