KR100688580B1 - Disk clamp and hard disk drive with the same - Google Patents

Abstract

A disk clamp and an HDD(Hard Disk Drive) with the clamp are provided to allow coupling units equipped with screw coupling holes to have a smaller degree of elastic transformation, therefore unfastening of fastened screws is prevented, consequently generation of disk slipping is prohibited. A receiving unit(131) is disposed on the center, and receives an upper protruded part(112a) of a spindle motor(110). Coupling units(132) are disposed on an outer side of the receiving unit(131), and are coupled with an upper side portion of the spindle motor(110) by fastening screws(150). Pressurizing units(138) are disposed on outer sides of the coupling units(132), and pressurize disks(107,108). The receiving unit(131) is in closed cap type of surrounding the upper protruded part(112a) of the spindle motor(110).

Description

Disk clamp and hard disk drive with the same

1 is a cross-sectional view showing an example of a conventional disk clamp.

2 is a perspective view showing a hard disk drive according to a preferred embodiment of the present invention.

3 and 4 are a perspective view and a cross-sectional view of a disk clamp according to a preferred embodiment of the present invention.

FIG. 5 is a graph showing the magnitude of the pressing force at a specific point of the pressing unit when the disk clamps of FIGS. 3 and 4 are fastened to the spindle motor.

<Description of Symbols for Main Parts of Drawings>

100 ..hard disk drive 101 ..base member

105 ..cover member 107, 108 ..disc

110 ..Spindle motor 111 ..Motor bracket

112 ..motor shaft 113 ..motor hub

120 .. Actuator 122 .. Swing arm

125 .. slider 128 ..boy coil motor

130 ..disc clamp 131 ..receptor

132 .. Fasteners 133 .. Screw fasteners

138 ..Pressure part 150 ..Screw

The present invention relates to a hard disk drive, and more particularly, to a disk clamp for fixing a disk, which is a data storage medium, to a spindle motor as a driving means, and a hard disk drive having the same.

A hard disk drive (HDD) is an example of an auxiliary memory device mounted in a host system such as a computer, a mobile phone, an MP3 player, or a set-top box. The hard disk drive (HDD) is used to store data stored on a disk, a data recording medium by a magnetic head. A device that plays back or records new data on a disc.

1 is a cross-sectional view showing an example of a conventional disk clamp.

Referring to FIG. 1, the disk clamp 10 is for fixing the disk 1, which is a data recording medium, to the spindle motor 5, which is a rotation driving means, and the shaft 6 of the spindle motor 5 is fitted therein. A central through hole 11, a fastening part 12 provided outside the through hole 11, and a pressing part 15 provided outside the fastening part 12 are provided. The fastening part 12 is provided with a plurality of screw fastening holes 13 through which the plurality of screws 20 pass. The disk clamp 10 is fixed to the motor hub 8 by the screws 20 penetrating through the screw fastening hole 13 and inserted into the motor hub 8 that is the rotor of the spindle motor 5. The pressing unit 15 presses the disk 1 to fix the disk 1 to the motor hub 8. The fastening portion 12 is not flat but inclined inclined. When the screw 20 is tightened, the fastening part 12 is elastically deformed and is stretched so that the bottom surface of the fastening part 12 is in close contact with the flat top surface of the motor hub 8.

However, since the elastic deformation degree of the fastening portion 12 due to tightening the screw 20 is large, the elastic restoring force of the fastening portion 12 to return to its original shape is increased, which may lead to loosening of the screw 20. Big. Such a poor tightening of the screw 20 causes a lack of the pressing force of the disk 1, so that a so-called disk slip, in which the disk 1 slides in the horizontal direction during rotation, is increased. In addition, the tightening degree of the plurality of screws 20 may not be constant, and a partial deformation may be caused in the inner circumference of the disk 1 pressed by the pressing unit 15.

The present invention is to solve the above problems, to provide a disk clamp and a hard disk drive having an improved structure to minimize the elastic deformation of the fastening portion fastened to the spindle motor to be a technical problem.

In order to achieve the above technical problem, the present invention is to secure a disk, which is a data recording medium to the spindle motor, the receiving portion which is provided in the center, the upper projection of the spindle motor; A fastening part provided on an outer side of the receiving part and fastened to an upper part of the spindle motor by tightening a screw; And a pressing part for pressing the disk, which is provided at an outer side of the fastening part, wherein the receiving part has a closed disk cap shape surrounding the upper protrusion of the spindle motor. Provide one hard disk drive.

Preferably, the fastening portion is elastically deformed in a direction that is concave inclined with respect to the upper portion of the spindle motor flattened by screw tightening, it can be configured to cause the pressing force of the pressing portion due to this elastic deformation.

Preferably, the disk contact surface of the pressing portion may be a curved surface convex downward.

Preferably, the fastening portion may be provided with a plurality of screw fastening holes arranged at equal intervals.

Hereinafter, with reference to the accompanying drawings will be described in detail a disk clamp and a hard disk drive having the same according to a preferred embodiment of the present invention. Figure 2 is a perspective view showing a hard disk drive according to a preferred embodiment of the present invention. .

Referring to FIG. 2, the hard disk drive 100 according to an exemplary embodiment of the present invention includes a housing having a predetermined internal space formed by combining the base member 101 and the cover member 105. In addition, the housing includes first and second disks 107 and 108, which are data recording media, a spindle motor 110 for rotationally driving the disks 107 and 108, and an actuator 120. The base member 101 and the cover member 105 are usually made of stainless steel or aluminum. The spindle motor 110 includes a motor bracket 111 fixedly mounted to the base member 101, a motor hub 113 serving as a rotor, and a motor shaft 112 serving as a rotation center axis of the motor hub 113. It is provided. Disks 107 and 108 penetrate and are stacked on the motor hub 113, and a spacer 115 is interposed between the disks 107 and 108 to separate the stacked disks 107 and 108. do. The disk clamp 130 is fastened by tightening the screw 150 to the upper portion of the motor hub 113. The disk clamp 130 elastically presses the disks 107 and 108 to fix them to the motor hub 113.

The actuator 120 is a device for recording data on the disks 107 and 108 or reading the recorded data. The actuator 120 is rotatably installed on the base member 101. The actuator 120 includes a swing arm 122 pivotally coupled to the base member 101 about the pivot bearing 127, a suspension 123 coupled to the distal end of the swing arm 122, and A slider 125 supported by the suspension 123. The slider 125 is equipped with a magnetic head (not shown) for recording and reproducing data. The actuator 120 also provides a voice coil motor 128 that provides a driving force for pivoting the swing arm 122. It is provided. The voice coil motor 128 is controlled by a servo control system, and in a direction in accordance with Fleming's left hand law due to the interaction of a current input to a VCM coil (not shown) and a magnetic field formed by a magnet (not shown). The swing arm 122 is rotated. Accordingly, the slider 125 attached to the tip of the suspension 123 is directed toward the spindle motor 110 on the first and second disks 107 and 108 or toward the outer circumference of the disks 107 and 108. Will be moved in the direction.

3 and 4 are a perspective view and a cross-sectional view of a disk clamp according to a preferred embodiment of the present invention.

3 and 4, the disc clamp 130 includes a receiving part 131 into which the upper protrusion 112a of the motor shaft 112 of the spindle motor 110 is fitted, and the receiving part 131. The fastening part 132 provided on the outer side and the pressurizing part 138 provided on the outer side of the fastening part 132 are provided. The disk clamp 130 is made of a metal such as spring steel, and may be formed by press working. The receiving portion 131 is in the form of a closed cap that encloses and receives the upper protrusion 112a of the motor shaft 112 in its inner groove.

The fastening part 132 is provided with six screw fastening holes 133, and six screws 150 are fastened to the upper side of the motor hub 113 by passing through the screw fastening holes 133. The screw fastening holes 133 are arranged at an equiangular interval with respect to the center of the circular disk clamp 130 so that the screw 150 may be evenly distributed in the upper portion of the motor hub 113. Accordingly, the angles A1 formed by the two adjacent screw fastening holes 133 with respect to the center of the disc clamp 130 are all 60 degrees, and the sizes thereof are substantially the same within the tolerance range.

The upper surface 113a of the motor hub 113 is flat, but the fastening part 132 is concave inclined with respect to the upper surface 113a of the motor hub 113. When the screw 150 is tightened, the fastening part 132 elastically deforms and expands so that the bottom surface 132a of the fastening part 132 is close to the top surface 113a of the motor hub 113, and the pressing part 138 is caused by this elastic force. ) A pressing force is induced.

As described above, the pressing unit 138 presses the disks 107 and 108 with the pressing force caused by the elastic deformation of the fastening unit 132, and fixes the disks 107 and 108 to the motor hub 113. The bottom surface 138a of the pressing portion 138 in contact with the inner circumferential portion 108a of the second disk 108 is below so that the point of contact with the inner circumferential portion 108a and the contacted area can be kept constant. To form a convex surface. The curved bottom surface 138a is also effective in preventing deformation of the disc inner circumferential portion 108a due to pressure load concentration. The thickness of the pressing portion 138 is thicker than the thickness of the fastening portion 132 and the elastic deformation portion 135. This is to prevent the pressing portion 138 from being deformed due to the reaction force of the disk inner peripheral portion 108a being pressed.

The closed receptacle 131 in the form of a cap reinforces the rigidity of the disc clamp 130. That is, stress applied to the fastening part 132 due to tightening of the screw 150 is distributed to the receiving part 131 so that the fastening part 132 of the fastening part 132 as compared to the conventional disk clamp 10 (see FIG. 1). Deformation degree becomes small. Thus, loosening of the tightened screw 150 is suppressed.

Computer simulation by the inventors of the present invention was performed to compare and verify the effect of the disk clamp 130 with the conventional disk clamp 10 (see FIG. 1). In this simulation, a hard disk drive with two 69-millimeter-thick disks was assumed, and six screws were assumed to be tightened with a force of 3.5 kgfcm.

FIG. 5 is a graph showing the magnitude of the pressing force at a specific point of the pressing unit when the disk clamps of FIGS. 3 and 4 are fastened to the spindle motor. Specifically, the horizontal axis of the graph is shown as an angle with respect to the center of the disk clamp (10, 130) the position of a specific point in the pressing portion of the disk clamp (10, 130) according to the conventional and the present invention. The vertical axis of the graph represents the magnitude of the pressing force applied to the inner periphery of the disc at that particular point.

Referring to FIG. 5, graphs (i) and (ii) respectively corresponding to the conventional and the embodiments of the present invention are generally sinusoidal, the maximum pressing force is repeated every 60 degrees, and the minimum pressing force is repeated every 60 degrees. . Referring to FIG. 3, the point at which the maximum pressing force appears is a specific point in the pressing unit 138 positioned on an imaginary straight line connecting the center of the disk clamp 130 and the screw fastening hole 133. The point at which the minimum pressing force appears is a specific point located between the points at which the maximum pressing force appears. 5, in the case of the conventional disk clamp 10, the magnitude of the pressing force applied to the disk is severe (see graph (i)), but in the case of the disk clamp 130 of the embodiment of the present invention, the change is relative. It is confirmed that it has been alleviated by (see graph (ii)).

Table 1 below summarizes the results of the simulations performed by the inventors of the present invention.

Conventional Inventive Example Displacement of fastening part [mm] 0.332 0.2451 Displacement rate One 0.7383 Force change rate One 0.9661

Displacement of the fastening part represents the displacement of the screw fastening hole of the fastening part moved downward by tightening the screw, the disk clamp 130 of the embodiment of the present invention is smaller than the conventional disk clamp 10, the displacement of the fastening part. From this, it can be predicted that the disk clamp 130 of the embodiment of the present invention is less elastically deformed than the conventional disk clamp 10, so that the possibility of screw tightening will be less than that of the conventional disk clamp 10. . On the other hand, the displacement variation rate represents the ratio of the displacement of the coupling portion of the disk clamp 130 according to the embodiment of the present invention to the displacement of the coupling portion of the conventional disk clamp 10.

The rate of change in the pressing force is described with reference to the graph (i) and the graph (ii) of FIG. 5, and the maximum of the disk clamp 130 according to the embodiment of the present invention with respect to the difference between the maximum and minimum pressing force of the conventional disk clamp 10. The ratio of the difference between the pressing force and the minimum pressing force is shown. Through this, it can be seen that the deviation of the pressing force in the disk clamp 130 of the embodiment of the present invention is smaller than the deviation of the pressing force in the conventional disk clamp 10. This means that when the disk clamp 130 according to the embodiment of the present invention is employed as compared with the conventional disk clamp 10, a relatively uniform pressing force may be applied to the inner circumferential surface of the disk.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. For example, the screw fastening of the disc clamp is not limited to six, eight, twelve, and so on. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

In the disk clamp of the present invention, the fastening portion in which the screw fastening hole is formed has a smaller degree of elastic deformation than the fastening portion of the conventional disk clamp. This prevents loosening of the tightened screws, thereby preventing the occurrence of disc slip.

In addition, since a uniform pressing force is applied to the disc inner circumferential portion as compared with the conventional case, deformation of the disc inner circumference portion is suppressed.

Claims (8)

By fixing the disk of the hard disk drive to the spindle motor, Receiving portion provided in the center, for receiving the upper projection of the spindle motor; A fastening part provided on an outer side of the receiving part and fastened to an upper part of the spindle motor by tightening a screw; And, And a pressurizing part provided on an outer side of the fastening part to pressurize the disk. And the receiving portion is in the form of a closed cap surrounding the upper protrusion of the spindle motor. According to claim 1, And the fastening portion is elastically deformed in a direction inclined concave with respect to the upper portion of the spindle motor and flattened by screw tightening, and the elastic deformation causes a pressing force of the pressing portion. According to claim 1, And the disk contact surface of the pressing portion is curved downwardly convex. According to claim 1, And a plurality of screw fastening holes arranged at equal angle intervals in the fastening part. A hard disk drive comprising at least one disk as a data recording medium, a spindle motor for rotating the disk, and a disk clamp for fixing the disk to the spindle motor. Receiving portion provided in the center, for receiving the upper projection of the spindle motor; A fastening part provided on an outer side of the receiving part and fastened to an upper part of the spindle motor by tightening a screw; And a pressurizing part provided on an outer side of the fastening part to pressurize the disk. And the receiving portion is in the form of a closed cap surrounding the upper protrusion of the spindle motor. The method of claim 5, The fastening portion is elastically deformed in a direction inclined concave with respect to the upper side of the spindle motor flattened by screw tightening, the elastic deformation is a hard disk drive, characterized in that the pressing force of the pressing portion is induced. The method of claim 5, And the disk contact surface of the pressing portion is a curved surface which is convex downward. The method of claim 5, And a plurality of screw fastening holes arranged at equal angle intervals in the fastening part.

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