KR100471613B1 - A motor structure fixed a shaft - Google Patents

Abstract

Improved load capacity to cope with load load by adopting a large number of platters to record and / or record a large amount of information, and fluids using pneumatic bearings and oils of a certain viscosity Disclosed is a shaft fixed motor structure in which a dynamic pressure bearing is used together to prevent dry friction at the initial stage of driving and to secure a discharge path of static electricity generated during driving. The structure includes a housing (100) in which a core (130) wound around a coil is fixed to an inner central portion and fixed to a lower fixture; A fixed block 180 having one end fixed to the center of the housing and a coupling groove 81 formed at the other end thereof; A shaft 140 positioned at the center of the coupling groove 181 and fixed to the fixed block 180 at a lower end thereof; A sleeve 120 which is rotatably coupled to the coupling groove 181 while simultaneously forming an oil gap therebetween to form a fluid dynamic bearing; The center is coupled to the sleeve 120 is rotated together, the magnet 160 for generating an electromagnetic force by the interaction with the core 130 is attached to the inner end surface of the extended extension end is attached, the fixed block 180 A hub 150 formed with an air dynamic bearing for forming an air gap by forming an air gap between the outer diameter surface and the upper surface; First and second thrust plates 171 and 172 which are respectively fixed to upper and lower portions of the shaft 140 and which form a hydrodynamic bearing surface between the sleeves 120; The upper end cap 210 is fixedly coupled to the upper end of the sleeve 120 and rotatably supported on the upper end of the shaft 140. The shaft fixed type motor structure uses the shaft 140 as a fixed body and prevents the occurrence of vibration due to the degradation of rigidity by using the hub 150 on which a plurality of platters 400 are mounted as a rotating body. In addition, by using the fixed body of the shaft 140 to prevent the stiffness deterioration occurs during high-speed rotation, it is possible to mount a large number of platters 400 to store a large amount of information. In addition, by employing a fluid dynamic bearing and a pneumatic hydraulic bearing together to minimize the occurrence of dry friction between the rotor and the stator during driving of the motor to prevent wear and improve the driving characteristics of the motor.

Description

A motor structure fixed a shaft

The present invention relates to a shaft-mounted motor structure, and in particular, to improve the load load capacity to cope with the load load by employing a plurality of platters to record and / or record a large amount of information and In addition, the pneumatic bearing and the hydrodynamic bearing using the oil of constant viscosity are used together to prevent the dry friction at the beginning of driving and to secure the discharge path of static electricity generated during the driving.

Recently, the hard disk drive (HDD) is a trend that requires a large recording capacity due to the increased use of multimedia. In addition, in the case of a HDD for a server in which a large amount of information is moved and stored, there is a continuous demand for large capacity.

Such a large capacity HDD can be obtained by increasing the recording density of the platter or increasing the number of platters. In order to increase the recording density of the platter, the non-repeatable runout (NRRO) must be small during rotation. This reduction of NRRO has been made by the hydrodynamic bearing replacing the conventional ball bearing.

On the other hand, when only a hydrodynamic bearing is used, the viscosity of the oil decreases due to frictional heat generated in the oil at high speed rotation, and thus the load bearing capacity of the dynamic bearing decreases, thereby degrading the performance of the motor.

On the other hand, pneumatic bearings do not cause any change in physical properties or load bearing capacity due to frictional heat at high speed, but they generate dry friction during initial start-up of the motor and thus hinder the role of the bearing.

However, such a method of increasing the recording density of the platter requires considerable effort and time since the entire HDD system needs to be improved.

On the other hand, the increase in the number of platters can be achieved through effective design of the bearings and the rotation system of the spindle motor of the HDD, and the capacity of the platters can be obtained by accommodating the system of the platter and the HDD with the improved recording density as it is, and thus obtaining the larger capacity It can be said that to increase the effective.

The present invention was created to solve the above problems, and has the following object.

First, to provide a shaft fixed motor structure with improved load capacity of the rotor to increase the number of platters (platters) rotated together to the hub 50 to ensure a stable drive even in pursuit of a large capacity drive (HDD) have.

Second, to provide a shaft fixed type motor structure with improved structure to reduce the initial dry friction of the pneumatic bearing bearing to rotate the rotating portion by the air dynamic pressure generated in the gap between the fixed portion and the rotating portion of the motor.

The shaft fixed-type motor structure of the present invention to achieve the above object is the core is coiled around the inner core is fixed and the housing fixed to the lower fixed body; A fixed block having one end fixed to the center of the housing and having a coupling groove formed at the other end thereof; A shaft which is positioned at the center of the coupling groove and whose lower end is coupled and fixed to the fixed block; A sleeve which forms an oil gap between the shaft and is rotatably coupled to the hydrodynamic bearing while being rotatably coupled to the coupling groove; The central portion is coupled to the sleeve and rotated together, and a magnet for generating electromagnetic force by interaction with the core is attached to the inner end surface of the extended end portion extending downward, between the outer diameter surface and the upper surface of the fixed block. A hub having an air dynamic bearing for forming an air gap to form air dynamic pressure; First and second thrust plates each of which is fixed to upper and lower portions of the shaft and forms a hydrodynamic bearing surface between the sleeves; It is characterized in that the upper end cap is fixed to the upper end of the sleeve and rotatably supported on the upper end of the shaft.

In addition, the upper closing cap is formed in an annular shape so as to be rotatably coupled to the shaft, the upper end of the shaft is characterized in that fixed to the upper fixing body.

According to the above characteristics of the present invention, the motor structure of the present invention has a structure in which one end or both ends of the shaft is fixed, so that when the weight of the rotating body such as an increase in the number of platters is increased, the load of the conventional motor shaft is rotated. The capability is improved to enable stable driving. In addition, the shaft fixed type motor structure of the present invention adopts a pneumatic bearing and a hydrodynamic bearing together to prevent dry friction occurring in the early stage of driving of the motor, and when the motor structure of the present invention is employed in a hard disk drive (HDD), It secures a path for releasing static electricity to the outside to stabilize the operating characteristics of the motor.

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

Since the motor structure of the embodiment of the present invention is fixed at one end or both ends of the shaft, a plurality of platters are mounted on the hub so that a stable ball is possible despite the large load, and the air dynamic bearing has a certain viscosity. Fluid Dynamic Bearing using oil is used together to minimize the initial friction and to release the static electricity generated during driving, thereby improving the driving characteristics of the motor.

Referring to FIG. 1 showing such a shaft fixed motor structure of the present invention, it has a structure in which a rotor is rotatably supported by a bearing means against a stator including a shaft 140. The bearing means forms an oil gap in which oil is received between the rotor and the stator to generate fluid dynamic pressure, and an air gap in which air is introduced between the rotor and the stator generates air dynamic pressure. An air dynamic bearing is provided.

The stator includes a housing (100) in which a core (130) wound around a coil is fixed to an inner central portion thereof and fixed to a lower fixture (310); A fixed block 180 having one end fixed to the center of the housing 100 and a coupling groove 81 formed at the other end thereof; A shaft 140 positioned at the center of the coupling groove 181 and fixed to the fixed block 180 at a lower end thereof; And first and second thrust plates 171 and 172 which are respectively fixed to upper and lower portions of the shaft 140 to form a fluid dynamic bearing surface between the sleeve 120 to be described later.

The rotor has a sleeve (120) which is rotatably coupled to the coupling groove (181) while forming an oil gap between the shaft (140) to form a hydrodynamic bearing; The center is coupled to the sleeve 120 is rotated together, the magnet 160 for generating an electromagnetic force by interaction with the core 130 is attached to the inner end surface of the extended end portion extending downward, the fixed block ( A hub 150 having an air dynamic bearing formed therebetween to form an air gap by forming an air gap C between the outer surface and the upper surface of the 180; The upper end cap 210 is fixedly coupled to the upper end of the sleeve 120 and rotatably supported on the upper end of the shaft 140.

Reference numeral 220 is a lower closing cap that is fixedly coupled to the shaft 140, by forming a fluid groove (not shown) on the outer circumferential surface so that the fluid dynamic pressure between the sleeve 120 can be formed.

The hydrodynamic bearing is provided between the shaft hole of the sleeve 120 and the shaft 140, and the pneumatic hydrodynamic bearing is provided with the inner circumferential surface of the hub 150 opposite to the outer circumferential surface and the upper surface of the fixed block 18. Is provided between.

The sleeve 120 and the hub 150 are supported in a radial direction by the air dynamic pressure flowing into the air gap C, and the sleeve 120 is supported by the air dynamic pressure flowing into the air gap D. And the hub 150 in the thrust direction.

On the other hand, referring to Figure 2 showing another embodiment of the motor structure of the present invention, which is a structure in which both ends of the shaft 140 is fixed, the upper and lower ends have a structure fixed to the upper and lower fixing bodies 310, 320, respectively. Since the remaining components have the same structure as the above embodiment, detailed description thereof will be omitted.

In the shaft fixed type motor structure of the present invention as described above, the shaft 140 having a smaller diameter and a greater length and smaller rigidity as a fixed body is used as the fixed body, and the hub 150 on which a plurality of platters 400 are mounted is rotated. By using it to prevent the occurrence of vibration, etc. due to the decrease in rigidity. In addition, by using the shaft 140 as a stationary body, it is possible to mount a plurality of platters 400 by increasing the rigidity, so that a large amount of information can be stored.

The motor structure of the present invention configured as described above has a hub 150 and a sleeve for the stator including the housing 100, the fixed block 180, the core 130, and the shaft 140 when power is applied to the core 130. The rotor composed of 120 is to be relatively rotated.

The oil filled between the fixed shaft 140 and the rotating sleeve 120 forms a high pressure while being concentrated in a fluid groove (not shown) to form a fluid dynamic bearing.

In addition, a fluid dynamic bearing in a thrust direction is formed between the upper and lower thrust plates 171 and 172 and the sleeve 120.

As described above, the shaft 140 is smoothly rotated by the fluid dynamic bearing formed in the fluid groove (not shown) and the fluid dynamic bearing in the thrust direction.

On the other hand, the air dynamic bearing acts together with the fluid dynamic bearing when the motor is driven. That is, as the hub 150 is rotated with respect to the fixed shaft 140, the air flowing into the air gap C and D forms the air dynamic pressure through the air groove (not shown), and thus, the fixed block 180. The hub 150 is supported in the radial direction and the thrust direction.

Therefore, during the initial driving of the motor to prevent the dry friction between the fixed block 180 and the hub 150 constituting the pneumatic hydrodynamic bearing by the hydrodynamic bearing around the shaft 140, through the oil employed in the hydrodynamic bearing Smooth discharge of generated static electricity.

The fluid groove and the air groove are formed in a herringbone shape or a spiral shape.

The present invention as described above is not limited to the above embodiments without departing from the spirit and scope of the present application can be practiced with a number of modifications.

The present invention as described above has the following advantages.

First, compared to other parts of the motor structure, the shaft 140 having a small diameter and a large length and small rigidity is used as the fixed body, and the rigidity is reduced by using the hub 150 on which a plurality of platters 400 are mounted as a rotating body. To prevent the occurrence of vibration, etc. In addition, by using the shaft 140 as a stationary body, it is possible to mount a plurality of platters 400 by increasing the rigidity, so that a large amount of information can be stored.

Secondly, by employing a fluid dynamic bearing and an air hydraulic bearing together, the occurrence of dry friction between the rotor and the stator is minimized when the motor is driven, thereby preventing wear and improving the driving characteristics of the motor.

Third, it is possible to smoothly discharge the static electricity generated by the air friction in the gap between the pneumatic bearings, thereby to stabilize the operating characteristics of the motor.

1 is a cross-sectional view showing a shaft fixed motor structure of an embodiment of the present invention;

2 is a cross-sectional view showing another embodiment of the motor structure according to the present invention.

* Explanation of symbols for main parts of the drawings

100 ... Housing 120 ... Sleeve

130 ... core 140 ... shaft

150 ... hub 160 ... magnet

171,172 ... Thrust Plate 180 ... Fixed Block

210 Top cap 400 400 Platter

Claims (2)

A core (100) in which a coil is wound around an inner center thereof and fixed to a lower fixture; A fixed block 180 having one end fixed to the center of the housing 100 and a coupling groove 181 formed at the other end thereof; A shaft 140 positioned at the center of the coupling groove 181 and fixed to the fixed block 180 at a lower end thereof; A sleeve 120 that forms an oil gap between the shaft 140 and is rotatably coupled to form a hydrodynamic bearing and is rotatably coupled to the coupling groove 181 at the same time; The center is coupled to the sleeve 120 is rotated together, the magnet 160 for generating an electromagnetic force by interaction with the core 130 is attached to the inner end surface of the extended end portion extending downward, the fixed block ( A hub 150 in which an air gap bearing is formed to form an air gap by forming an air gap between the outer diameter surface and the upper surface of the 180; First and second thrust plates (171) (172) fixed to upper and lower portions of the shaft (140) and forming a hydrodynamic bearing surface between the sleeve and the sleeve (120); Shaft-fixed motor structure, characterized in that the upper end cap 210 is fixed to the upper end of the sleeve 120 and rotatably supported on the upper end of the shaft 140. According to claim 1, wherein the upper closing cap 210 is formed in an annular shape to be rotatably coupled to the shaft 140, The upper end of the shaft 140, the fixed shaft motor structure, characterized in that fixed to the upper body.