JP5001551B2 - Hard disk drive - Google Patents

Description

  The present invention relates to a hard disk drive, and more particularly to the structure of a head stack assembly of a hard disk drive.

  The hard disk drive includes, for example, a magnetic disk on which information is recorded, a head for reading and writing information provided facing the magnetic disk, and a head stack assembly that holds the head and rotates it to a predetermined position on the magnetic disk (Head Stack Assembly; hereinafter referred to as “HSA”). The HSA is configured by stacking a suspension for holding a head on a bearing portion that serves as a shaft for rotational driving.

  The conventional HSA is fixed by, for example, fastening a component constituting the HSA such as a suspension or an overmold by screwing a nut to a pivot constituting the bearing portion and fastening the nut (for example, Patent Document 1 FIG. 3). . The conventional pivot 10 includes, for example, a shaft 11, a bearing 13, and a main body 15 as shown in FIGS. 5 (a) and 5 (b). The main body 15 is a housing that covers the shaft 11 and the bearing 13 inserted through the shaft 11 and has a cylindrical shape. A flange portion 17 is formed on one side (upper side in FIG. 5A) of the main body portion 15, and a nut is screwed on the other side (lower side in FIG. 5A) of the main body portion 15. A thread groove 19 is formed. As shown in FIG. 5B, the flange portion 17 of the pivot 10 has notches 17a for suppressing the rotation of the pivot 10 when the nut is screwed to the pivot 10 so that they are parallel to each other at two locations. Is formed.

  In order to fix the suspension 20 and the like using the pivot 10, first, as shown in FIG. 6A, the pivot 10 and the nut 50 constitute an HSA, for example, a pair of the suspension 20 and the overmold 30. From above and below. Then, the notch 17a of the pivot 10 is fixed by pivot fixing means (not shown), and the pivot 10 and the nut 50 are screwed together via the washer 40. In this way, as shown in FIG. 6B, the suspension 20 and the overmold 30 are fixed by the flange portion 17 of the pivot 10 and the nut 50.

JP-A-11-250434

  However, when fixing the components of the HSA using a nut fastening method, stress is generated on the components constituting the HSA such as the suspension when the nuts are tightened, resulting in the performance and quality of the HSA. It will have an effect. Specifically, when the nut is tightened, stress is applied in the direction of the rotation axis, and the base plate of the suspension is warped and the overmold is deformed. For this reason, the heights of the suspension and the head vary and a problem occurs in the positional relationship with the magnetic disk. In addition, since the nut is tightened in the rotation direction of the suspension, there is a problem that stress in the twisting direction is generated on the suspension.

  Furthermore, since the size of the components of the conventional HSA is extremely different between the upper and lower sides of the bearing, the HSA cannot be balanced, and in particular, the ratio of the nut to the height of the bearing is large. The entire height of the hard disk drive had to be increased.

  Further, a notch for suppressing the rotation of the pivot when the pivot and the nut are fastened is formed in the pivot flange portion constituting the bearing portion. For this reason, the shape of the washer that holds the suspension from the side facing the flange portion of the pivot is different from the shape of the flange portion of the pivot, and the magnitude of stress applied to the suspension from the vertical direction is different. This causes a problem that the deformation state is different between the upper and lower portions of the suspension.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved hard disk drive capable of reducing stress applied to HSA components. There is to do.

  In order to solve the above problems, according to an aspect of the present invention, a head for reading and writing information on an information recording surface of a magnetic disk, a suspension that supports the head, a pivot that rotatably supports the suspension, A hard disk drive is provided that includes a flange cap that mates with a pivot. Here, the suspension is sandwiched from above and below by fitting the pivot and the flange cap.

  In the present invention, for example, a pivot and a flange cap are fitted between a pair of suspensions via an overmold, and the suspension and the overmold are sandwiched from above and below. With such a configuration, when the suspension is fixed, stress in the direction of the rotating shaft or the twist direction that adversely affects the suspension is not generated. Thereby, the performance and quality of HSA can be stabilized.

  Further, the assembly in which the pivot and the flange cap are fitted may be formed so as to have a vertically symmetrical shape. As a result, the center of gravity of the HSA in the height direction (rotational axis direction) can be made more central, and the balance of the HSA can be improved. Further, since the number of parts constituting the bearing can be reduced, the height of the HSA can be reduced. Therefore, the overall thickness of the hard disk drive can be reduced.

  Further, a step portion can be formed on the pivot, and a flange cap can be fitted to the step portion. By forming such a stepped portion, the shape of the assembly in which the pivot and the flange cap are fitted can be easily formed in a vertically symmetrical shape.

  As described above, according to the present invention, it is possible to provide a hard disk drive capable of reducing stress applied to HSA components.

  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.

  First, the overall configuration of the hard disk drive according to the embodiment of the present invention will be described with reference to FIGS. Here, FIG. 1 is a plan view showing the configuration of the hard disk drive according to the present embodiment. FIG. 2 is an explanatory diagram for explaining the configuration of the HSA according to the present embodiment.

  As shown in FIG. 1, the hard disk drive 100 according to the present embodiment includes, for example, a disk drive device, an HSA 200, and a voice coil motor 300. The disk drive device includes, for example, a magnetic disk 110 in which data is written and data can be stored, and a spindle motor 120 that rotates the magnetic disk 110. The HSA 200 includes a head 210 that writes data to and reads data from the magnetic disk 110, a suspension 220 that holds the head 210, and a pivot 230 that serves as a rotary bearing portion of the HSA 200. The HSA 200 is rotationally driven by using a voice coil motor 300 and a coil (not shown) provided in an overmold of the HSA 200 as drive sources.

  As shown in FIG. 2, the HSA 200 according to the present embodiment is provided, for example, such that a pair of suspensions 220 constituting the HSA 200 are provided so that the heads 210 that are respectively held are opposed to each other with an overmold 310 having a coil interposed therebetween. Yes. The pair of suspensions 220 and the overmold 310 are fixed so as to be sandwiched between a pivot 230 and a flange cap 240 constituting a bearing portion.

  Next, based on FIG. 3 and FIG. 4, the structure of the bearing part of HSA200 concerning this embodiment is demonstrated. Here, FIG. 3A is a side view showing the pivot 230 according to the present embodiment, and FIG. 3B is a plan view showing the pivot 230 according to the present embodiment. 4 is an explanatory view showing a method of fixing the suspension 220 by the pivot 230 and the flange cap 240 according to the present embodiment. FIG. 4A shows a state before the pivot 230 and the flange cap 240 are fitted together. FIG. 5B shows a state after the pivot 230 and the flange cap 240 are fitted.

  As shown in FIG. 3A, the pivot 230 according to this embodiment includes a shaft 231, a bearing 233, and a main body 235. The main body 235 is a housing that covers the shaft 231 and the bearing 233 inserted through the shaft 231, and has a cylindrical shape with a flange 237 formed on one side. For example, a step portion 235 c is formed in the main body portion 235, and a large diameter portion 235 a is formed on the flange portion 237 side, and a small diameter portion 235 b is formed on the opposite side to the flange portion 237. Moreover, as shown in FIG.3 (b), the flange part 237 is formed in the disk shape.

  The present embodiment is characterized in that the overmold 310 and the pair of suspensions 220 are fixed using the flange cap 240 fitted to the pivot 230. As shown in FIG. 4A, the flange cap 240 is a fitting member that is fitted to the pivot 230 on which the flange portion 241 is formed, and has a diameter substantially the same as the outer diameter of the small diameter portion 235b of the pivot 230. A through hole 243 is formed. Further, the outer diameter of the main body portion of the flange cap 240 is formed substantially the same as the outer diameter of the large diameter portion 235 a of the pivot 230. Then, the overmold 310 and the pair of suspensions 220 sandwiching the overmold 310 are sandwiched by the pivot 230 and the flange cap 240 from above and below.

  Then, the pivot 230 and the flange cap 240 are fitted. As a result, as shown in FIG. 4B, the pair of suspensions 220 and the overmold 310 are fixed by the flange portion 321 of the pivot 230 and the flange portion 241 of the flange cap 240.

  Here, as a method of fixing using the pivot 230 and the flange cap 240, for example, there is a press-fitting method of press-fitting the flange cap 240 into the pivot 230. In this case, the pivot 230 and the flange cap 240 are configured to have an interference fit between the small diameter portion 235b of the pivot 230 and the through hole 243 of the flange cap 240.

  Alternatively, an adhesive method in which an adhesive is applied to the outer periphery of the small diameter portion 235b of the pivot 230 to fix the flange cap 240 can be applied. In this case, only the small diameter portion 235b of the pivot 230 formed by providing the step portion 235c on the pivot 230 as in the present embodiment and the inside of the through hole 243 of the flange cap 240 may be bonded, and the suspension 220 is pivoted. The flange portion 237 of 230 and the flange portion 241 of the flange cap 240 need not be fixed with an adhesive. Here, as the adhesive, for example, a UV resin that is cured by ultraviolet irradiation can be used. In addition, the procedure for adhering and fixing may be to apply the adhesive to the outer periphery of the small diameter portion 235b of the pivot 230 or the inside of the flange cap 240, and then fit the pivot 230 and the flange cap 240 together. After fitting 240, an adhesive may be injected into the fitting portion.

  In this way, the pivot 230 and the flange cap 240 can be fixed to the HSA 200 without applying stress such as strong tightening or twisting by using a press-fitting method or an adhesion method. Therefore, the suspension 220 and the overmold 310 are not twisted or deformed, and the quality of the HSA 200 can be stabilized.

  Further, the pivot 230 and the flange cap 240 according to the present embodiment are not screwed as in the prior art, but are fitted in the direction of the rotation axis, so that it is necessary to form a notch in the flange portion 237 of the pivot 230. There is no. Therefore, the flange portion 237 of the pivot 230 positioned in the vertical direction of the suspension and the flange portion 241 of the flange cap 240 have substantially the same shape, and therefore the magnitude of stress applied from the vertical direction of the suspension 220 is substantially the same. Thereby, the problem that the deformation state differs between the upper and lower portions of the suspension 220 does not occur. Moreover, the operation | work which forms a notch in the flange part 237 of the pivot 230 can also be skipped.

  Further, as shown in FIG. 4B, the assembly 250 formed by fitting the pivot 230 and the flange cap 240 has a vertically symmetrical shape. That is, in the state of the assembly 250 in which the pivot 230 and the flange cap 240 are fitted, the center line between the flange portion 237 of the pivot 230 and the flange portion 241 of the flange cap 240 is symmetric. The pivot 230 and the flange cap 240 are formed. For this reason, the center of gravity is located at the approximate center in the vertical direction of the assembly 250, and the HSA 200 has a balanced configuration. Further, since the fixing position of the suspension 220 and the overmold 310 is substantially the center of the assembly 250, the HSA 200 can be easily positioned with respect to the height of the magnetic disk 110.

  Moreover, in the fixing method of HSA200 concerning this embodiment, the number of parts required in order to fix the components of HSA200, such as suspension 220, can be reduced. In particular, as shown in FIG. 6B, it is not necessary to use parts having a large proportion of the height, such as washers 40 and nuts 50, which have been conventionally used for fixing the components of the HSA 200. Therefore, the height of the HSA 200 can be reduced by the thickness of the washer 40 and the nut 50 as compared with the conventional case. Thereby, the thickness of the entire hard disk drive 100 can be reduced.

  The embodiment of the hard disk drive according to the present invention has been described above. Thus, by forming a flange cap that fits into the pivot, and fixing the HSA component by fitting the pivot and the flange cap together, the stress applied to the HSA component can be reduced.

  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 the example which concerns. 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 embodiment, the pivot 230 is provided on the upper side of the assembly 250 and the flange cap 240 is provided on the lower side. However, the present invention is not limited to this example, and the flange cap 240 on the upper side and the pivot 230 on the lower side. May be provided.

  Further, when the bonding method described in the above embodiment for fixing the pivot 230 and the flange cap 240 using an adhesive is applied, a groove may be formed in the small diameter portion 235b of the pivot 230 along the outer peripheral direction. Good. As a result, the adhesive flows into the groove, and the joint between the pivot 230 and the flange cap 240 can be strengthened.

  Furthermore, the pivot 230 according to the above embodiment is a shaft thread type (Shaft Thread Type) pivot, but the present invention is not limited to such an example. It may be a shaft screw type (Shaft Screw Type) pivot.

  The present invention can be applied to a hard disk drive, and in particular, can be applied to the structure of a head stack assembly of a hard disk drive.

It is a top view which shows the structure of the hard-disk drive concerning embodiment of this invention. It is explanatory drawing for demonstrating the structure of HSA concerning the embodiment. The pivot concerning the embodiment is shown, (a) is a side view, (b) is a plan view. It is explanatory drawing which shows the fixing method of the suspension by the pivot and flange cap concerning the embodiment, (a) shows the state before fitting a pivot and a flange cap, (b) shows a pivot, a flange cap, The state after fitting is shown. The conventional pivot is shown, (a) is a side view, (b) is a plan view. It is explanatory drawing which shows the fixing method of the suspension by the conventional pivot and nut, (a) shows the state before screwing a pivot and a nut, (b) shows the state after screwing a pivot and a nut. Show.

Explanation of symbols

100 hard disk drive 110 magnetic disk 200 HSA
210 Head 220 Suspension 230 Pivot 231 Shaft 233 Bearing 235 Body 235a Large diameter 235b Small diameter 235c Stepped portion 237 Flange 240 Flange cap 241 Flange 243 Through hole 250 Assembly 300 Voice coil motor 310 Overmold

Claims (2)

A head for reading and writing information on the information recording surface of the magnetic disk;
A suspension for supporting the head;
A pivot that rotatably supports the suspension;
A flange cap mating with the pivot;
With
The suspension is fitted to the outer circumference of the pivot and the outer circumference of the flange cap, and is sandwiched from above and below by fitting the pivot and the flange cap .
The pivot includes a flange portion, a small diameter portion, and a large diameter portion provided between the flange portion and the small diameter portion and having a larger outer diameter than the small diameter portion,
The outer diameter of the large diameter portion of the pivot and the outer diameter of the flange cap are substantially the same,
A step portion is formed between the large diameter portion and the small diameter portion of the pivot,
A hard disk drive , wherein the flange cap is fitted to the small diameter portion .   2. The hard disk drive according to claim 1, wherein the assembly in which the pivot and the flange cap are fitted has a vertically symmetrical shape.

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