JP2007115380A - Disk drive and magnetic disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk drive device capable of reducing height of the disk drive itself. <P>SOLUTION: A disk drive 100 is equipped with a hub 150 having a spindle motor 130 and an overhanging part 150e for supporting a disk medium 170 of a ring shape by a head part of the hub of the spindle motor 130 and an outer-circumference side of the spindle motor 130, and a clamp 190 for clamping the disk medium 170 with the overhanging parts 150e of the hub 150. The clamp 190 has the ring shape fitted to the outer circumference of the head part of the hub and is also equipped with an elastic ring for fixing the clamp 190. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a disk drive device and a magnetic disk device including the same.

  In recent years, with the miniaturization and thinning of portable music players, for example, magnetic disk devices mounted on such portable music players are also required to be small and thin.

  In general, a magnetic disk device includes a disk drive device including a disk medium for storing information, and a head stack assembly including a head for writing information to the disk medium and reading information from the disk medium. In a disk drive that rotates a disk medium at a predetermined high speed, the disk medium is sandwiched between members called a hub and a clamp and fixed to the disk drive.

  As a disk drive device as described above, a disk drive device 10 as shown in FIG. 4 is disclosed. FIG. 4 is an enlarged cross-sectional view of the disk drive device 10. As shown in FIG. 4, the disk drive device 10 includes a base 11, a spindle motor 13 provided on the base 11, and a disk medium 17 placed on the hub 15. A female screw groove 13 a is formed on the rotation shaft 13 b of the spindle motor 13. A disk medium 17 is placed on a hub 15 provided on a sleeve 13c of the spindle motor 13. The placed disk medium 17 is connected to the hub 15 and a clamp 19 having a substantially Ω-shaped cross section. It is pinched. Then, the clamp 19 is fixed by a clamp screw 21 having a male screw thread 21a so as to be screwed with a female screw groove 13a formed in the rotating shaft 13b of the spindle motor 13 so that the disk medium 17 does not move. By fixing the clamp 19 in this way, an elastic force is applied to the clamp 19, and the disk medium 17 interposed between the hub 15 and the clamp 19 can be effectively held (for example, Patent Document 1). reference.).

  If the 3.5-inch magnetic disk device used in an ordinary desktop personal computer or the 2.5-inch magnetic disk device used in an ordinary notebook personal computer, the thickness of the magnetic disk device itself is sufficient. Can be secured. Therefore, even if the clamp is fixed by the method using the clamp screw as described above, there is no problem that the height of the disk drive device is limited by the thickness of the housing of the magnetic disk device.

JP 2004-234793 A

  However, when manufacturing a very small and thin magnetic disk device of, for example, less than 1 inch, all components essential to the magnetic disk device must be housed in a small and thin housing. For this reason, even the height of a component that does not cause a problem in a 3.5-inch or 2.5-inch magnetic disk drive is often a problem. In particular, the periphery of the disk drive unit installed in the housing of the magnetic disk unit must accommodate a large number of parts, so that the performance of the product is improved and the height of the components is made as much as possible. It was necessary to overcome the difficult problem of reducing the size and reducing the thickness of the magnetic disk drive.

  In particular, in the disk drive device, since the clamp is clamped and fixed by fastening the clamp screw, it is difficult to further reduce the height of the disk drive device and to reduce the thickness.

In addition, when the height of the spindle motor called the radial bearing length (for example, h ₂ in FIG. 4) is reduced to reduce the height dimension, the rigidity of the spindle motor also decreases. As a result, the motor characteristics deteriorate, and there is a problem that high power is required to rotate the disk medium. In addition, when the height of the motor is reduced by shortening the protruding part of the motor, it becomes difficult to fasten the hub and the fastening length of the clamp screw is shortened, so the clamp screw securely fixes the clamp. There is a possibility that the stability of fixing the disk medium may be problematic.

  Therefore, there has been a demand for a method for reducing the height of the disk drive device itself without reducing the height of the spindle motor.

  Therefore, the present invention has been made in view of such problems, and an object of the present invention is to use a new and improved disk drive device capable of reducing the height of the disk drive device itself and the same. It is to provide a magnetic disk device.

  In order to solve the above-mentioned problems, the inventors of the present invention conducted intensive research. As a result, the inventors have arrived at an invention capable of reducing the height of the disk drive device itself as described below.

  That is, in order to solve the above problems, according to one aspect of the present invention, a spindle motor; a hub head held at the tip of the spindle motor; and a ring-shaped disk medium supported on the outer peripheral side of the spindle motor A disk drive device comprising: a hub having an overhanging portion; and a clamp for sandwiching the disk medium between the overhanging portion of the hub, wherein the clamp is an extrapolated ring on the hub head A disk drive device having a shape and further comprising an elastic ring for fixing the clamp is provided.

  By forming the disk drive device as described above, the disk medium is held by the clamp and the disk medium mounting surface, which is a flat surface on the hub head side in the overhanging portion of the hub, and the clamping force is exhibited and the disk is exerted. The medium is fixed to the spindle motor. For this reason, a clamp screw for clamping and fixing the clamp becomes unnecessary, and the height of the disk drive device itself can be reduced.

  An annular groove may be formed on the outer periphery of the hub head, and the elastic ring may be fitted into the annular groove. With this configuration, the elastic ring for fixing the clamp is securely fixed to the hub.

  The overhang portion of the hub has a flat surface in contact with the inner peripheral portion of the disk medium, and the flat surface extends to a position corresponding to the inner peripheral end surface of the disk medium. Also good. With this configuration, the disk medium can be stably placed. Furthermore, since the position where the clamp fixes the disk medium can be positioned on the spindle motor side, the disk medium can be provided with a wide data area, which is an area where data can be stored.

  The hub may be integrally formed with the spindle motor. Since the hub is integrally formed with the spindle motor, the rotational force obtained by the spindle motor can be reliably transmitted to the hub.

  The elastic ring may be made of a fluorine rubber. This fluorine rubber is excellent in heat resistance and heat distortion resistance, and does not discharge outgas, so that the disk drive can be operated more stably. Here, outgas means a gas component generated from a part.

  The clamp may be formed of SUS300 series having elasticity. In addition, the clamp may be formed of an elastic alloy having softness and capable of processing a thin shape. By forming the clamp using the material as described above, the disk medium can be effectively held.

  In order to solve the above problems, according to another aspect of the present invention, a magnetic disk device including the above disk drive device is provided. The magnetic disk device provided with the disk drive device as described above can reduce the height of the disk device itself, and the magnetic disk device can be made smaller and thinner.

  According to the present invention, it is possible to provide a disk drive device and a magnetic disk device using the same that can reduce the height of the magnetic disk device itself without reducing the height of the spindle motor.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  A preferred embodiment of the present invention will be described below in detail by taking, as an example, a disk drive device used in a magnetic disk device of less than 1 inch. However, the disk drive device and the magnetic disk device of the present invention are not limited to the above-mentioned size, and for example, a magnetic disk device of 1 inch or more such as 2.5 inches or 3.5 inches, Needless to say, the present invention is also applicable to disk drive devices used in these magnetic disk devices.

  FIG. 1 is a plan view schematically showing the magnetic disk device according to the first embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of the disk drive device 100 taken along the line AA in FIG.

  As shown in FIG. 1, the magnetic disk device 500 according to the present embodiment includes, for example, a disk drive device 100, a head stack assembly 300, and a voice coil motor 400. The disk drive device 100 includes, for example, a disk medium 170 on which data is written and can store data, and a spindle motor 130 that rotates the disk. The disk drive device 100 will be described in detail below. The head stack assembly 300 is a part used for writing data to the disk medium 170 and reading data from the disk medium 170, and the part actually used for reading and writing data is located at the tip of the head stack assembly 300. This is a head 310 provided. The head stack assembly 300 operates using a voice coil motor 400 and a coil (not shown) provided in the head stack assembly 300 as drive sources.

  The head 310 floats from the disk medium 170 at an interval of, for example, about 10 nanometers. Therefore, if dust or outgas exists in the magnetic disk device 500, the operation of the magnetic disk device 500 is abnormal. Will come. Therefore, the inside of the disk device 500 must be kept clean so that even a slight amount of dust and outgas does not occur. Therefore, the parts constituting the magnetic disk device must also be formed using a material that does not generate dust or outgas.

  Next, the disk drive device 100 will be described in detail with reference to FIG. As shown in the figure, the following description will be given with the horizontal direction of the disk drive device 100 as the x-axis direction and the height direction of the disk drive device 100 as the y-axis direction.

  The disk drive device 100 according to the present embodiment includes, for example, a substantially rectangular plate-shaped base 110, a substantially cylindrical spindle motor 130, and a disk medium 170 placed on the hub 150.

  A spindle motor 130 for rotating the disk medium 170 has, for example, a substantially cylindrical shape and is disposed on the base 110. As the spindle motor 130, it is possible to use one having an arbitrary mechanism such as a ball bearing mechanism or a fluid bearing mechanism. However, from the viewpoint of positioning accuracy and noise suppression, a spindle motor having a fluid bearing mechanism is used. Preferably 130 is used.

  The hub 150 is one of the parts constituting the spindle motor 130 and is formed integrally with the spindle motor 130. The hub 150 includes a ceiling part 150a, an annular groove 150c, a side wall part 150d, an overhang part 150e, a notch part 150f, and a flat surface 150g, which are integrally formed. The end of the ceiling 150a is chamfered so that, for example, the disk medium 170 or the like can be easily extrapolated. An annular groove 150c is formed on the outer peripheral side of the ceiling portion 150a along the circumferential direction on the outer peripheral side. Further, a side wall 150d is integrally formed from the lower end 150b of the ceiling 150a toward the negative y-axis direction in FIG. 2, and from the lower end of the side wall 150d, along the x-axis direction in FIG. , An overhang 150e is formed. The hub head is composed of the ceiling 150a and the side wall 150d. Further, the upper surface of the overhang 150e, that is, the surface in the positive y-axis direction is formed to be a flat surface 150g, and the outer peripheral end of the flat surface 150g is chamfered as shown in FIG. Yes. Further, a notch 150f having a substantially triangular cross section is formed along the outer periphery of the side wall 150d at the joint between the flat surface 150g and the side wall 150d. The hub 150 is used to transmit the rotational force obtained by the spindle motor 130 to the disk medium 170, and the flat surface 150g of the hub 150 is used to support the disk medium 170 as a disk medium mounting surface.

  The disk medium 170 is a rigid body formed in a ring shape, and its diameter is a major factor that determines the size of the magnetic disk device. At the center of the disk medium 170, a through hole (not shown) having a diameter substantially the same as the outer diameter of the side wall 150d of the hub 150 is provided concentrically with the center of the disk. This through hole is extrapolated to the side wall 150d of the hub 150, and is supported by being in surface contact with a flat surface 150g provided on the overhang 150e of the hub 150.

  If the disk medium 170 is only supported by the flat surface 150g of the hub 150, the disk medium 170 may be lifted and detached when the disk medium 170 rotates at a high speed. Therefore, the disk medium 170 is fixed to the flat surface 150 g of the hub 150 by the clamp 190. The clamp 190 is a member formed from an elastic alloy. The alloy having elasticity is preferably an alloy having both flexibility and rigidity and capable of processing a thin shape. As an example of the above alloy, for example, an alloy such as SUS300 series can be used. The SUS300 series is a stainless steel material defined by the JIS standard (JIS G4308). The clamp 190 has a substantially ring shape, and is formed so that the side cross section has a substantially Ω-shape as shown in FIG. A through-hole (not shown) having a diameter substantially the same as the outer diameter of the side wall 150 d of the hub 150 is provided in the center of the clamp 190 concentrically with the clamp 190. When the clamp 190 is externally inserted into the side wall 150 d of the hub 150, the clamp 190 exhibits a clamping force, and the disk medium 170 is sandwiched between the flat surface 150 g of the hub 150 and the clamp 190.

  FIG. 3A is an enlarged cross-sectional view showing an overhang portion 150e of the hub 150 according to the present embodiment, and FIG. 3B is an enlarged cross-sectional view showing an overhang portion 15e of the conventional hub 15.

  Referring to FIG. 3A, the overhanging portion 150e of the hub 150 has a flat surface 150g that contacts the inner peripheral portion of the disk medium 170, as described above. It extends to a position corresponding to the peripheral end face. On the side wall 150d of the hub 150, a notch 150f having a substantially triangular cross section is formed along the outer periphery of the side wall 150d at the joint with the overhang 150e. Referring to FIG. 3B, in the conventional hub 15, a notch portion 15 f having a substantially trapezoidal cross section is provided along the circumferential direction of the hub 15 on the inner peripheral side of the overhang portion 15 e of the hub 15. It can be seen that the overhang 15e has a substantially convex cross section.

  Conventionally, the projecting portion 15e of the hub 15 is formed by first cutting the hub from the upper side to the lower side along the vertical direction of the hub, and then moving from the outer periphery of the hub toward the inner periphery along the horizontal direction of the hub. It has been done by scraping. At this time, even if the machining is performed with as high accuracy as possible, the portion at the end of cutting becomes a cross-sectional R shape. However, in order to place the disk medium stably, the cross section at the end of the cutting needs to be perpendicular. Therefore, when machining in the vertical direction, extra cutting has been performed in the vertical direction to obtain the right-angled cross section. At that time, a notch 15 f having a substantially trapezoidal cross section as shown in FIG. 3B is formed in the overhang 15 e of the hub 15 along the circumferential direction of the hub 15. As a result, the overhanging portion 15e of the hub 15 has a substantially convex cross section as shown in FIG. 3B.

  However, in the hub 150 according to the present embodiment, in order to form the overhang 150e of the hub 150, first, cutting is performed in the horizontal direction, that is, the x-axis direction in FIG. Then, in order to perform cutting from the upper side to the lower side along the vertical direction, that is, in the negative y-axis direction of FIG. It will be formed along the direction. As a result, the overhang 150e of the hub 150 can have a wide flat surface 150g as shown in FIG. 3A.

  The overhanging portion 150e of the hub 150 in this embodiment supports the disk medium 170 by the wide flat surface 150g described above, so that the disk medium 170 is stably supported by the hub 150. Further, since the disk medium 170 is supported on a wider flat surface than the conventional one, the position A where the clamp 190 presses and fixes the disk medium 170 is changed to the conventional position B as shown in FIGS. 3A and 3B. Compared to, it can be moved to the rotating shaft side.

  As described above, by moving the position A where the clamp 190 presses and fixes the disk medium 170 to the inner peripheral side, a large data area can be secured in the disk medium 170, and the amount of information that can be stored is increased. Can be achieved.

  As shown in FIG. 2, the clamp 190 provided as described above is fixed by a clamp fixing rubber 210 that is an elastic ring. The clamp fixing rubber 210 is formed using an elastic body that has heat resistance, heat deformation resistance, and the like and does not generate outgas. As such a material, for example, fluorine rubber is particularly preferable. This fluorine-based rubber has already been proven as a material for forming a crash stop mechanism (not shown) provided in the disk device, and is excellent in that no outgas is generated. The clamp fixing rubber 210 formed of the material as described above is fitted into an annular groove 150c formed in the hub 150, and fixes the clamp 190.

  By fixing the clamp 190 with the above configuration, the height of the clamp screw 21 and the clamp 19 represented by the height T in FIG. As a whole, the height of the disk drive device 100 (corresponding to H in FIG. 2) can be reduced.

In general rigidity of the spindle motor is dependent on the radial bearing (radial bearing) of the spindle motor, referred to as length height (corresponding to _{h 2} of _{h 1} and 4 in FIG. 2), the higher the height of the motor , Stiffness also increases. The disk drive device according to the present embodiment eliminates the need for the clamp screw and the female screw groove of the spindle motor to which the clamp screw is screwed, which are indispensable members of the conventional disk drive device. of the, for example, as h ₁ in FIG. 2, it is possible to extend to the vicinity of the upper surface of the hub 150. Therefore, it is possible to show a higher motor rigidity than a conventional disk drive device having the same thickness.

  A method for manufacturing the disk drive device 100 according to the present embodiment will be briefly described as follows.

  As a first step, a spindle motor 130 in which the hub 150 is integrally formed is disposed on a base 110 that has been subjected to predetermined processing. Subsequently, as a second step, the disk medium 170 is placed on the overhang 150 e of the hub 150. In the subsequent third step, the clamp 190 formed of the SUS300 series is mounted on the disk medium 170, and the disk medium 170 is sandwiched between the hub 150 and the clamp 190. Subsequently, as a fourth step, the clamp 190 is fixed by fitting the clamp fixing rubber 210 formed of fluorine-based rubber into the annular groove 150 c of the hub 150. In this way, the disk drive device 100 according to the present embodiment can be manufactured.

  In manufacturing the disk drive device 100 according to the present embodiment, it is not necessary to form a female screw groove in the spindle motor as in the prior art, so that it is possible to save labor. Further, since the clamp is fixed with rubber which is an elastic member, it is possible to save assembling work as compared with the conventional method of screwing a clamp screw.

  By using the disk drive device 100 according to the present embodiment formed in this manner together with other members constituting the magnetic disk device, a smaller and thinner magnetic disk device can be manufactured.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above description, the annular groove 150c is provided in the hub 150, and the clamp fixing rubber 210 for fixing the clamp 190 is fitted into the annular groove 150c. However, a protrusion is provided on the upper part of the annular groove 150c. The clamp fixing rubber 210 may be fixed integrally with the hub.

  The present invention is applicable to a disk drive device and a magnetic disk device including the disk drive device.

1 is a plan view schematically showing a magnetic disk device according to a first embodiment of the present invention. 1 is an enlarged cross-sectional view of a disk drive device according to a first embodiment of the present invention. It is the expanded sectional view which showed the overhang | projection part of the hub which concerns on the 1st Embodiment of this invention. It is the expanded sectional view which showed the overhang | projection part of the conventional hub. It is an expanded sectional view of the conventional disk drive device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Disc drive device 11 Base 13 Spindle motor 13a Female thread groove 13b Rotating shaft 13c Sleeve 15 Hub 15e Overhang portion 15f Notch 15g Flat surface 17 Disc medium 19 Clamp 21 Clamp screw 21a Male screw thread 100 Disc drive device 110 Base 130 Spindle motor 150 Hub 150a Ceiling part 150b Lower end 150c Annular groove 150d Side wall part 150e Overhang part 150f Notch part 150g Flat surface 170 Disk medium 190 Clamp 210 Clamp fixing rubber 300 Head stack assembly 310 Head 400 Voice coil motor 500 Magnetic disk apparatus

Claims (7)

A spindle motor; a hub having a hub head held at a tip of the spindle motor; and a projecting portion that supports a ring-shaped disk medium on an outer peripheral side of the spindle motor; and the projecting portion of the hub In a disk drive comprising a clamp for sandwiching the disk medium therebetween:
The clamp has a ring shape to be extrapolated to the hub head;
A disk drive device further comprising an elastic ring for fixing the clamp. An annular groove is formed on the outer periphery of the hub head,
2. The disk drive device according to claim 1, wherein the elastic ring is fitted into the annular groove. The projecting portion of the hub has a flat surface in contact with the inner peripheral portion of the disk medium,
3. The disk drive device according to claim 1, wherein the flat surface extends to a position corresponding to an inner peripheral end surface of the disk medium.   The disk drive device according to claim 1, wherein the hub is integrally formed with the spindle motor.   The disk drive device according to claim 1, wherein the elastic ring is made of fluorine-based rubber.   6. The disk drive device according to claim 1, wherein the clamp is formed of elastic SUS300 series. A magnetic disk device comprising the disk drive device according to claim 1.

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