Cover manufacturing method and cover

Abstract

To provide a method for manufacturing a cover capable of reducing the dimension of the cover in a thickness direction.SOLUTION: A method includes: forming a fastening surface portion 29 for fastening with a relatively thin wall while allowing plastic flow during crushing by a locator hole 33, by providing the locator hole 33 in an outer peripheral portion 17a of a plate-shaped cover semi-finished product 41 and crushing a part of the outer peripheral portion 17a of the cover semi-finished product 41 in a thickness direction; forming a step portion 31 that surrounds the fastening surface portion 29 with respect to a part of an outer peripheral edge 17b of the outer peripheral portion 17a before or after forming the fastening surface portion 29 and biases it in the thickness direction; and providing a fastening hole 29c in the fastening surface portion 29, and making the locator hole 33 in parallel to the outer peripheral edge 17b and making at least a part of the locator hole position inside an imaginary line 35 that is in contact with the outer peripheral edge 17b in a surface direction of the portion being the fastening hole 29c.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a cover used in a recording device such as a hard disk drive, and to a cover. [Background technology]

[0002] A hard disk drive as a recording device accommodates a disk, which is a recording medium, in a housing, as described in Patent Document 1. The housing is configured by fastening a plate-shaped cover to a base that accommodates the disk.

[0003] The cover has a plurality of fastening surfaces on its outer periphery. The fastening surfaces are positioned to be biased toward the base in the thickness direction relative to the rest of the cover due to stepped portions. The fastening surfaces are fastened to the base by fasteners such as screws.

[0004] Although this structure can prevent the heads of the screws and the like from protruding from the surface of the cover, it has the problem of increasing the overall dimension in the thickness direction.

[0005] To address this issue, it is possible to reduce the overall thickness by reducing the dimensions of the step portion of the cover, but this is only possible to the extent that the heads of screws and other components do not protrude from the surface of the cover, so there is a limit to how much the overall thickness can be reduced. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 10,373,652 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved is that there is a limit to how much the cover can be reduced in thickness. [Means for solving the problem]

[0008] The present invention provides a method for manufacturing a cover to be attached to the base of a recording device by fastening, the method comprising: providing a waste hole in the outer periphery of a plate-shaped cover semi-finished product; crushing a portion of the outer periphery of the cover semi-finished product in the thickness direction to form a fastening surface portion for fastening that is relatively thin while allowing plastic flow during the crushing via the waste hole; forming a step portion that surrounds the fastening surface portion against the outer peripheral edge of the portion of the outer periphery and biases it in the thickness direction before or after forming the fastening surface portion; providing a fastening hole in the fastening surface portion; and positioning the waste hole parallel to the outer periphery and at least a portion of the waste hole inside a virtual line that contacts the outer edge in the surface direction of the portion that will become the fastening hole.

[0009] The present invention also provides a plate-shaped cover that is attached to the base of a recording device by fastening, the cover comprising: a fastening surface portion for fastening that is formed relatively thin by crushing a part of the outer periphery in the thickness direction; a fastening hole provided in the fastening surface portion; a step portion that surrounds the fastening surface portion against the outer peripheral edge of the part of the outer periphery and biases it in the thickness direction; and a discard hole that is parallel to the outer peripheral edge and has at least a portion located inside an imaginary line that touches the outer edge in the surface direction of the fastening hole, and that allows plastic flow when the fastening surface portion is crushed. [Effects of the Invention]

[0010] The method for manufacturing a cover of the present invention can reliably form a thin fastening surface by crushing, and can easily and reliably reduce the dimension of the cover in the thickness direction.

[0011] The cover of the present invention can reliably reduce the dimension in the thickness direction of the cover by having the fastening surface portion reliably thinned by crushing. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a rear view of a cover used in a recording apparatus according to a first embodiment of the present invention. [Figure 2] 2A is a schematic cross-sectional view of the recording device corresponding to the line II-II of the cover in FIG. 1, and FIG. 2B is a schematic cross-sectional view of a recording device according to a modified example, corresponding to FIG. 2A. [Figure 3] FIG. 3 is a schematic cross-sectional view showing a part of the recording apparatus of FIG. 2(A). [Figure 4] FIG. 4 is a schematic cross-sectional view showing the fastening surface portion of the cover of FIG. 3 and its surroundings. [Figure 5] 5 is a schematic plan view showing the fastening surface of the cover of FIG. 3 and its surroundings. [Figure 6] FIG. 6 is a schematic plan view showing the fastening surface portion of the cover according to the modified example and its periphery. [Figure 7] FIG. 7 is a schematic plan view showing the fastening surface portion and its periphery of a cover according to another modified example. [Figure 8] FIG. 8 is a schematic plan view showing the fastening surface portion and its periphery of a cover according to yet another modified example. [Figure 9] FIG. 9 is a schematic plan view showing the fastening surface portion and its periphery of a cover according to yet another modified example. [Figure 10] 10(A) to 10(D) are schematic cross-sectional views showing a method for manufacturing the cover according to the first embodiment. [Figure 11] FIG. 11 is a schematic plan view showing the outer periphery of the semi-finished cover of FIG. 10(A). [Figure 12] 12(A) to 12(C) are schematic cross-sectional views showing a method for manufacturing a cover according to Example 2 of the present invention. [Figure 13] 13(A) to 13(C) are schematic cross-sectional views showing a method for manufacturing a cover according to a third embodiment of the present invention. [Figure 14] 14(A) to 14(C) are schematic plan views showing a method for manufacturing a cover according to a fourth embodiment of the present invention. [Figure 15] FIG. 15 is a schematic cross-sectional view showing a method for manufacturing a cover according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention achieves the object of reducing the dimension of the cover in the thickness direction by forming the fastening surface portion for fastening to the base thin by crushing.

[0014] That is, in the manufacturing method of the cover 17, the outer periphery 17a of the plate-shaped cover semi-finished product 41 is provided with the dummy holes 33, and part of the outer periphery 17a of the cover semi-finished product 41 is crushed in the thickness direction to form the fastening surface 29 for fastening, which is relatively thin while allowing plastic flow during the crushing via the dummy holes 33. Before or after forming the fastening surface 29, a step 31 is formed that surrounds the fastening surface 29 with respect to part of the outer periphery edge 17b of the outer periphery 17a and biases it in the thickness direction, and a fastening hole 29c is formed in the fastening surface 29.

[0015] The waste hole 33 is parallel to the outer peripheral edge 17b and at least a portion thereof is located inside an imaginary line 35 that is in contact with the outer edge in the surface direction of the portion that will become the fastening hole 29c.

[0016] The fastening surface portion 29 may be formed by crushing not only a part of the outer peripheral portion 17a but also the surrounding area thereof before the step portion 31 is formed.

[0017] Before forming the fastening surface portion 29 and the step portion 31, the portion that will become the contour region 29e along the contour 29d of the fastening surface portion 29 may be crushed in advance.

[0018] After the fastening surface portion 29 is formed, the raised portion of the contour region 29e along the contour 29d of the fastening surface portion 29 may be removed to reduce the value of the parallelism of this contour region 29e.

[0019] The waste hole 33 may be formed so that a portion thereof is located in at least one of the portion that becomes the step portion 31 and the portion that becomes the fastening surface portion 29. In this case, the waste hole 33 may be located within the range of the portion that becomes the fastening surface portion 29, within the range of the portion that becomes the step portion 31, or within the range of the portion that becomes the fastening hole 29c. The waste hole 33 may have a shape that follows the portion that becomes the contour 29d of the fastening surface portion 29.

[0020] The semi-finished cover 41 may include a gasket receiving portion 27. The gasket receiving portion 27 is located on the inner side in the planar direction of a portion of the outer circumferential portion 17a of the semi-finished cover 41 that will become the step portion 31. In this case, the discard hole 33 is provided on the outer side of the gasket receiving portion 27 in the planar direction.

[0021] The cover 17 manufactured by the above manufacturing method includes a fastening surface portion 29, fastening holes 29c, a step portion 31, and a waste hole 33. The fastening surface portion 29 is formed relatively thin by crushing a portion of the outer periphery 17a in the thickness direction. The fastening holes 29c are provided in the fastening surface portion 29. The step portion 31 surrounds the fastening surface portion 29 with respect to a portion of the outer periphery edge 17b of the outer periphery 17a and biases the fastening surface portion 29 in the thickness direction. The waste hole 33 is parallel to the outer periphery edge 17b and at least a portion thereof is located inside an imaginary line 35 that is tangent to the outer edge of the fastening hole 29c in the planar direction, allowing plastic flow when the fastening surface portion 29 is crushed. [Example]

[0022] [Recording device configuration] FIG. 1 is a rear view of a cover used in a recording device according to a first embodiment of the present invention. FIG. 2(A) is a schematic cross-sectional view of the recording device corresponding to line II-II of the cover in FIG. 1, and FIG. 2(B) is a schematic cross-sectional view of a recording device according to a modified example and corresponding to FIG. 2(A). FIG. 3 is a schematic cross-sectional view showing a part of the recording device in FIG. 2(A). FIG. 4 is a schematic cross-sectional view showing the fastening surface of the cover in FIG. 3 and its periphery. FIG. 5 is a schematic plan view showing the fastening surface of the cover in FIG. 3 and its periphery.

[0023] As shown in FIGS. 1 and 2A, the recording device 1 is a hard disk drive serving as a magnetic disk device, and accommodates an internal mechanism (not shown) including a disk 5 serving as a recording medium in a space 3a within a housing 3.

[0024] A plurality of disks 5 are stacked and rotatably supported by a spindle shaft 7a of a spindle motor 7. Information is read from and written to these disks 5 via a head (not shown).

[0025] The recording device 1 is not limited to a magnetic disk device, but may be another disk device such as an optical disk device, or a recording device other than a disk device. For example, as shown in Fig. 2(B), the recording device 1 may be a tape-embedded drive. In this recording device 1, a tape film 11 serving as a recording medium wound between two tape reels 9, a head assembly 13 for reading and writing information, and the like are housed in a housing 3.

[0026] As shown in FIGS. 2A and 3, the housing 3 of the recording device 1 includes a base 15 and a cover 17, and the inside is closed or sealed.

[0027] The base 15 is configured in a box shape that is open on one side in the thickness direction of the recording device 1. The base 15 may have any suitable shape as long as it can accommodate the disc 5. The base 15 in this embodiment is, for example, in the shape of a box that is substantially rectangular in plan view.

[0028] The term "planar view" refers to a state seen from the thickness direction, and does not distinguish between the top and bottom surfaces. Furthermore, simply referring to the thickness direction means the thickness direction of the recording device 1. The material of the base 15 is a metal such as aluminum, but is not limited to this.

[0029] A cover 17 is attached to the opening in the thickness direction of the base 15 to close it, thereby sealing a space 3a within the housing 3 that accommodates the disk 5. This sealed space 3a may be filled with a gas such as helium that has less resistance than air.

[0030] A side wall 15a is provided around the outer periphery of the base 15, and the opening of the base 15 is defined by the side wall 15a. The outer periphery of the base 15 is the outer periphery area that surrounds the internal mechanism including the disk 5, and in this embodiment, refers to the portion where the side wall 15a is provided.

[0031] The side wall portion 15a is provided upright integrally from the plate-shaped bottom portion 15c of the base 15. However, the side wall portion 15a may also be formed as a separate piece from the bottom portion 15c of the base 15 and then joined to form an integral piece.

[0032] The side wall portion 15a is provided with a cover receiving portion 19 and a gasket receiving portion 21.

[0033] The cover receiving portion 19 of the base 15 is located at a portion where the cover 17 is fastened to the base 15. In this embodiment, the cover receiving portions 19 are provided at multiple locations, for example, six locations, spaced apart in the circumferential direction of the base 15. The cover receiving portions 19 may be formed in a circumferential shape along the outer periphery of the base 15. The circumferential direction of the base 15 means the circumferential direction along the side wall portion 15a of the base 15.

[0034] The cover receiving portion 19 receives the cover 17 by joining it in the thickness direction. In this joined state, the cover 17 is fastened to a fastening surface 19a of the cover receiving portion 19 of the base 15. In this embodiment, the fastening direction (hereinafter referred to as the fastening direction) coincides with the thickness direction.

[0035] However, the fastening direction does not have to be the same as the thickness direction, for example, it may be inclined relative to the thickness direction. It is also preferable that the joining direction of the cover 17 to the cover receiving portion 19 be the same as the fastening direction, but it does not have to be the same. In the following, the fastening direction and joining direction will be shown as the thickness direction unless otherwise required.

[0036] The fastening is performed by a fastener, for example, a bolt 23. The cover 17 is also fastened to the spindle shaft 7a of the spindle motor 7 by a bolt 24. In addition to the bolts 23 and 24, rivets or the like may also be used as the fastener.

[0037] The cover receiving portion 19 has a fastening surface 19a formed at an end in the thickness direction to fasten the cover 17. The fastening surface 19a of the cover receiving portion 19 is formed flat by a plane that intersects with the thickness direction. In this embodiment, the plane that forms the fastening surface 19a is perpendicular to the thickness direction.

[0038] However, the fastening surface 19a may be set to be slightly inclined with respect to the thickness direction. Also, the fastening surface 19a need not be flat as long as it can receive the cover 17 in the thickness direction.

[0039] Adjacent to the fastening surface 19a, an edge wall 15b is provided in the thickness direction on the side wall 15a of the base 15. The edge wall 15b is formed in a circumferential shape along the outer edge of the side wall 15a.

[0040] The gasket receiving portion 21 of the base 15 is a portion that receives the gasket 25 attached to the cover 17. By receiving the gasket 25, the gasket receiving portion 21 compresses the gasket 25 between the cover 17 and itself in the thickness direction, which is the direction in which the gasket 25 is fastened by the bolts 23. The gasket receiving portion 21 of the present embodiment is provided circumferentially along the side wall portion 15a of the base 15 in a plan view.

[0041] The gasket receiving portion 21 has a receiving surface 21a that receives the gasket 25. This receiving surface 21a is provided continuously around the outer periphery of the base 15 and receives the gasket 25 in the thickness direction. However, the receiving surface 21a may be provided partially on the outer periphery of the base 15.

[0042] The receiving surface 21a of the base 15 in this embodiment is formed as a flat surface similar to the fastened surface 19a of the base 15, and the fastened surface 19a of the base 15 is adjacent to it flatly.

[0043] The cover 17 attached to the base 15 has a fastening surface 29b joined to a fastening surface 19a of the base 15 and is fastened with bolts 23. This fastening intervenes between the cover 17 and the base 15, and a gasket 25 is interposed between the cover 17 and the base 15 to form the housing 3.

[0044] The cover 17 is made of a metal plate such as aluminum, and is formed as a flat plate that covers the opening of the base 15. In this embodiment, the cover 17 has a substantially rectangular shape in plan view to correspond to the base 15. However, the shape of the cover 17 is not particularly limited as long as it covers the opening of the base 15. The material of the cover 17 is also arbitrary.

[0045] The outer periphery 17a of the cover 17 is provided with a fastening surface 29. The outer periphery 17a of the cover 17 refers to the outer periphery area of ​​the main body of the cover 17 that covers the internal mechanism installed on the base 15.

[0046] The fastening surface portions 29 are plate-shaped portions that are joined to the fastened surface 19a of the base 15 and are fastened by the bolts 23. In this embodiment, the fastening surface portions 29 are formed in six locations on the outer circumferential portion 17a of the cover 17. The locations of the fastening surface portions 29 correspond to the cover receiving portions 19 of the base 15. Note that the fastening surface portions 29 may be provided continuously in the circumferential direction.

[0047] Each fastening surface portion 29 is formed by compressing a portion of the outer peripheral portion 17a of the cover 17 in the thickness direction, and is relatively thin-walled compared to the other portion 17c of the outer peripheral portion 17a of the cover 17 other than the fastening surface portion 29. The fastening surface portion 29 may be compressed by pressing. The fastening surface portion 29 extends inward from the outer peripheral edge 17b in the surface direction. The surface direction refers to the direction along the bolt-receiving surface 29a of the fastening surface portion 29.

[0048] The fastening surface portion 29 has a bolt receiving surface 29a and a fastening surface 29b. The bolt receiving surface 29a is the surface that receives the head 23a of the bolt 23 on the front side of the cover 17. The fastening surface 29b is the surface that is joined to and fastened to the fastened surface 19a of the base 15 on the back side of the cover 17. The bolt receiving surface 29a and the fastening surface 29b are flat surfaces that extend along the surface directions of the front and back surfaces of the cover 17. The front surface of the cover 17 is the surface that faces the outside of the cover 17 in the thickness direction, and the back surface of the cover 17 is the surface that faces the inside of the housing 3 of the cover 17 in the thickness direction.

[0049] The fastening surface portion 29 is allowed to undergo plastic flow when crushed by the countersink 33 described later, and the parallelism between the bolt receiving surface 29a and the fastening surface 29b is set to a small value.

[0050] The fastening surface portion 29 is biased toward the base 15 in the thickness direction by a step portion 31 relative to the other portion 17c of the outer circumferential portion 17a of the cover 17. Specifically, the step portion 31 sets the fastening surface portion 29 in a stepped shape that is concave on the front side of the cover 17 and convex on the back side.

[0051] The step portion 31 is provided so as to surround the fastening surface portion 29 relative to the outer peripheral edge 17b. As a result, the step portion 31 biases the fastening surface portion 29 in the thickness direction as a whole. The step portion 31 in this embodiment is an inclined plate-like shape that connects the fastening surface portion 29 to another portion 17c of the outer peripheral portion 17a of the cover 17. However, the step portion 31 may also be configured in a multiple-step shape, a half-punched shape, or the like.

[0052] The thickness (plate thickness) of the step portion 31 is the same as that of the other portion 17c of the outer periphery 17a of the cover 17, and is thicker than the fastening surface portion 29. However, the thickness of the step portion 31 may be thinner than that of the other portion 17c of the outer periphery 17a and the fastening surface portion 29, or may be the same as that of the fastening surface portion 29.

[0053] The step d1 caused by the step portion 31 is the step that the bolt receiving surface 29a has relative to the surface of the other part 17c of the outer periphery 17a, and the step d2 caused by the step portion 31 is the step that the fastening surface 29b has relative to the back surface of the other part 17c of the outer periphery 17a.

[0054] In this embodiment, the step d1 is the same as or slightly larger than the dimension in the thickness direction of the head 23a of the bolt 23. Note that the step d1 only needs to be equal to or larger than the dimension in the thickness direction of the head 23a of the bolt 23 so that the head 23a does not protrude from the surface of the cover 17.

[0055] Step d2 defines the compression height of gasket 25 in relation to receiving surface 21a of gasket receiving portion 21 of base 15. Step d2 is set to be smaller in dimension in the thickness direction by the amount corresponding to the thinning of fastening surface portion 29. On the other hand, if the compression height is not reduced, head 23a of bolt 23 can be made larger, and an increase in torque and breakage of bolt 23 can be suppressed.

[0056] Such step portion 31 defines a contour 29d of the fastening surface portion 29. As is clear from the back surface of the cover 17 in FIG. 1, the planar shape of the fastening surface portion 29 defined by the contour 29d is set to different shapes according to the fastening location, but basically has a shape that surrounds the periphery of the bolt 23.

[0057] A fastening hole 29c for the bolt 23 is formed in each fastening surface portion 29. The threaded portion 23b of the bolt 23 is inserted into this fastening hole 29c. In this way, the fastening surface portion 29 is fastened to the fastened surface 19a of the base 15 by the bolt 23 in a joined state.

[0058] 3 to 5, the fastening surface portion 29 of this embodiment is provided with a waste hole 33. The waste hole 33 is parallel to a part of the outer peripheral edge 17b of the outer peripheral portion 17a which is the fastening surface portion 29, and at least a part of the waste hole 33 is located inside an imaginary line 35 which is tangent to the outer edge of the fastening hole 29c in the surface direction, allowing plastic flow when the fastening surface portion 29 is crushed.

[0059] The term "inside" here refers to the side opposite the outer peripheral edge 17b with respect to the imaginary line 35. The outer edge in the surface direction of the fastening hole 29 refers to the part of the inner peripheral edge of the fastening hole 29 that is closest to the outer peripheral edge 17b in the surface direction.

[0060] The waste hole 33 is provided on the outer side in the planar direction of a gasket receiving portion 27 (described later) of the cover 17 that receives the gasket 25. Here, "outside" means the outer peripheral edge 17b side with the gasket receiving portion 27 as the boundary.

[0061] Therefore, the waste hole 33 is located between the gasket receiving portion 27 and the imaginary line 35 in the surface direction.

[0062] In this embodiment, the position of the waste hole 33 is within the range of the fastening surface portion 29. Specifically, the waste hole 33 is located closer to the innermost portion 29f (innermost portion 29f) of the fastening surface portion 29 and more inward than the fastening hole 29c.

[0063] The waste hole 33 is provided so as to penetrate the fastening surface portion 29. Note that the waste hole 33 does not have to penetrate the fastening surface portion 29 as long as it can allow plastic flow when the fastening surface portion 29 is crushed. The waste hole 33 may also be a cut or a slit. In this case, the edges on both sides of the waste hole 33 are shifted in the thickness direction.

[0064] The planar shape of the waste hole 33 is an arc shape corresponding to the contour 29d of the fastening surface portion 29. The width (radial width of the arc shape) of the waste hole 33 is set to a degree that will not close due to plastic flow when the fastening surface portion 29 is crushed. The planar shape, position, size, and range of the waste hole 33 can be set appropriately depending on the planar shape, crushing amount, parallelism, rigidity, etc. of the fastening surface portion 29.

[0065] 6 to 9 are plan views showing modified examples of the waste hole 33. FIG.

[0066] In the modified example of Fig. 6, the waste hole 33 of the embodiment of Fig. 5 is arranged so as to overlap the outline 29d of the fastening surface portion 29, and the waste hole 33 is provided from the step portion 31 to the fastening surface portion 29. Note that the waste hole 33 in this modified example is formed to have the same shape as in Fig. 5 after the step portion 31 is formed, but it may also be formed to have the same shape as in Fig. 5 before the step portion 31 is formed, in which case the part that overlaps the step portion 31 in plan view will have a different shape from that shown in Fig. 6. The same applies to the other modified examples.

[0067] The modified example shown in Fig. 7 has multiple waste holes 33 provided in the stepped portion 31. In this modified example, two waste holes 33 are provided. The waste holes 33 are each linearly arranged within the arc-shaped portion 31a of the stepped portion 31. The waste holes 33 are positioned symmetrically and inclined with respect to a line 37 that is perpendicular to the imaginary line 35 and passes through the center of the fastening hole 29c.

[0068] In the modification of FIG. 8, the waste hole 33 of FIG. 7 is biased toward the fastening hole 29c and arranged so as to straddle the contour 29d of the fastening surface portion 29, and the waste hole 33 is provided from the fastening surface portion 29 to the step portion 31.

[0069] In the modified example of Fig. 9, a plurality of waste holes 33 are provided from the step portion 31 to the fastening surface portion 29, similar to Fig. 6. However, in this modified example, the three arc-shaped waste holes 33 are arranged so as to be positioned on the same imaginary circle 39.

[0070] As shown in FIGS. 3 and 4, the cover 17 of this embodiment has a receiving surface 27a of the gasket receiving portion 27 of the cover 17 adjacent to the fastening surface portion 29 and facing the receiving surface 21a of the gasket receiving portion 21 of the base 15.

[0071] The receiving surface 27a of the cover 17 receives the gasket 25 in the thickness direction, which is the direction in which the cover is fastened by the bolts 23. In this embodiment, the receiving surface 27a of the cover 17 is provided circumferentially on the outer periphery 17a of the cover 17. However, the receiving surface 27a may be provided partially on the outer periphery 17a of the cover 17.

[0072] The receiving surface 27a is formed as a flat surface, similar to the receiving surface 21a of the base 15. However, the receiving surface 27a may have irregularities or the like.

[0073] A gasket 25 is attached to the receiving surface 27a of the cover 17. The gasket 25 may be attached to the receiving surface 21a of the base 15. The gasket 25 may be interposed between the receiving surfaces 27a and 21a without being attached thereto.

[0074] The gasket 25 seals or seals the gap between the cover 17 and the base 15, and is circumferentially shaped along the outer periphery 17a of the cover 17. The shape of the gasket 25 is arbitrary as long as it can seal or seal the gap between the cover 17 and the base 15.

[0075] The gasket 25 of this embodiment protrudes in the thickness direction from the receiving surface 27a of the cover 17, and its tip contacts the receiving surface 21a of the base 15. When the cover 17 is fastened to the base 15, the gasket 25 is compressed between the receiving surface 21a of the base 15 and the receiving surface 27a of the cover 17. Due to this compression, the gasket 25 has a compressed height equal to the step d2.

[0076] The gasket 25 of this embodiment is fixed along the receiving surface 27a of the cover 17. A liquid gasket such as a foamed-in-place gasket (FIPG) is used as the gasket 25. That is, the gasket 25 is applied to the receiving surface 27a of the cover 17 in advance, hardened, and fixed thereto.

[0077] Note that a liquid gasket, a molded gasket, or other suitable gasket can be used as the gasket 25. In the case of a molded gasket, it may be attached to the cover 17 in advance. Alternatively, an O-ring, packing, or the like may be used as the gasket 25.

[0078] The cross-sectional shape of the gasket 25 is a semicircular arc shape as a whole in the free state, so that the width of the gasket 25 gradually decreases from the middle to the tip in the thickness direction in the free state, and the gasket 25 has a barrel-shaped cross section between the cover 17 and the base 15 in the compressed state.

[0079] [Manufacturing methods for the cover and recording device] 10(A) to 10(D) are schematic cross-sectional views showing a method for manufacturing a cover according to Example 1, and FIG. 11 is a schematic plan view showing the outer periphery of a semi-finished cover.

[0080] The cover 17 of this embodiment is formed with the waste hole 33, the step portion 31, the fastening surface portion 29, and the fastening hole 29c in this order. Note that the step portion 31 may be formed before the waste hole 33 or after the fastening surface portion 29.

[0081] The waste holes 33 are formed by punching the outer periphery 17a of the plate-shaped semi-finished cover 41. Note that the same reference numerals are used for the components of the semi-finished cover 41 that correspond to those of the cover 17. The outer periphery 17a of the semi-finished cover 41 is an area having a predetermined width extending inward from the outer periphery 17b, which includes the portion that becomes the fastening surface 29.

[0082] In this embodiment, as shown in Figures 10(A) and 11, within the range of the portion that becomes the fastening surface portion 29, the waste hole 33 is located closer to the innermost portion 29f of the fastening surface portion 29 and more inward than the portion that becomes the fastening hole 29c.

[0083] The waste hole 33 may be formed so that a part of it is located in at least one of the portion that will become the step portion 31 and the portion that will become the fastening surface portion 29 .

[0084] The semi-finished cover 41 has been previously processed by pressing, punching, or the like, and has a generally flat plate shape with no fastening surface 29 or step 31 formed on the outer periphery 17a. However, the semi-finished cover 41 does not necessarily have to be a generally flat plate shape. In addition, the semi-finished cover 41 may remain with a part of its outer shell connected to the base material.

[0085] The outer periphery 17a of the semi-finished cover 41 has an outer contour corresponding to the outer periphery 17a of the cover 17. However, the outer periphery 17a of the semi-finished cover 41 may have an outer contour larger than the outer periphery 17a of the cover 17. In this case, the outer periphery 17a of the semi-finished cover 41 may be formed into an outer contour corresponding to the cover 17 in another process.

[0086] After the void hole 33 is formed, a step portion 31 is formed as shown in FIG. 10(B).

[0087] The step portion 31 is formed by displacing a portion of the outer periphery 17a that will become the fastening surface portion 29 in the thickness direction by pressing. That is, a portion of the outer periphery 17a of the semi-finished cover 41, from the outer peripheral edge 17b to the inside, is pressed with an upper mold 43 having a convex portion 43a corresponding to the step d2 of the step portion 31 and a lower mold 45 having a concave portion 45a corresponding to the step d2 of the step portion 31.

[0088] As a result, outer periphery 17a is partially inclined between the portion that becomes fastening surface 29 and other portion 17c, and the portion that becomes fastening surface 29 is displaced in the thickness direction relative to other portion 17c. As a result, step portion 31 is formed that surrounds fastening surface 29 relative to part of outer peripheral edge 17b of outer periphery 17a and displaces it in the thickness direction. However, in this case, step portion 31 has a step d2 on both the front and back of outer periphery 17a.

[0089] After the step portion 31 is formed, the fastening surface portion 29 is formed as shown in FIG. 10(C).

[0090] The fastening surface portion 29 is formed by pressing a portion of the outer periphery 17a of the cover semi-finished product 41 that will become the fastening surface portion 29 in the thickness direction, thereby making it relatively thin-walled while allowing plastic flow during crushing through the discard holes 33.

[0091] At this time, the waste hole 33 is formed so that a part of it is located on at least one of the portion that becomes the step portion 31 and the fastening surface portion 29, thereby allowing plastic flow when the fastening surface portion 29 is crushed even after the step portion 31 is formed. This makes it possible to crush the fastening surface portion 29 with less force, thereby reducing the value of parallelism and thinning the wall.

[0092] In this embodiment, plastic flow can be reliably permitted because the waste holes 33 are provided within the range of the portion that will become the fastening surface portion 29. Furthermore, the waste holes 33 within the range of the portion that will become the fastening surface portion 29 are located further outward in the surface direction than the portion that will become the outline 29d of the fastening surface portion 29, so plastic flow can be permitted all around.

[0093] When a blind hole 33 is provided within the stepped portion 31, as in the modified example of Figure 7, it is easy to ensure a sufficient contact area between the bolt receiving surface 29a and the head 23a of the bolt 23 while allowing for plastic flow during the formation of the fastening surface 29 by crushing. Furthermore, when the blind hole 33 straddles the stepped portion 31 and the portion that will become the fastening surface 29, as in the modified examples of Figures 6, 8, and 9, it is easy to ensure a sufficient contact area between the bolt receiving surface 29a and the head 23a of the bolt 23.

[0094] The fastening surface portion 29 is formed by crushing by pressing a portion of the outer circumferential portion 17a that will become the fastening surface portion 29 against a lower mold 45 using an upper mold 44. Note that by making the convex portion 43a of the upper mold 43 protrude by the amount of the fastening surface portion 29 that is crushed, it is possible to form the fastening surface portion 29 when forming the step portion 31.

[0095] In this way, the portion that will become the fastening surface portion 29 is compressed and plastic flow occurs in the surface direction. Plastic flow is more likely to occur toward the outer peripheral edge 17b and less likely to occur toward the opposite side of the outer peripheral edge 17b. Furthermore, plastic flow is more likely to occur in the direction along the step portion 31 and less likely to occur toward the step portion 31. For this reason, in this embodiment, waste holes 33 are provided in an area where plastic flow is less likely to occur, particularly in an area on the opposite side of the outer peripheral edge 17b (inside the imaginary line 35) along the step portion 31 that is not toward the outer peripheral edge 17b.

[0096] This eliminates areas where plastic flow is unlikely to occur. In particular, in this embodiment, by providing the waste holes 33 in the portion along the contour 29d passing through the innermost portion 29f of the fastening surface portion 29, it is possible to reliably eliminate areas where plastic flow is unlikely to occur. Therefore, the fastening surface portion 29 can be reliably formed with a thin wall overall, and the dimension of the cover 17 in the thickness direction can be easily and reliably reduced. Furthermore, as a result of reliably thinning the fastening surface portion 29, the value of parallelism can also be reduced.

[0097] The waste hole 33 is parallel to at least the outer peripheral edge 17b and at least a portion thereof is located inside an imaginary line 35 that contacts the outer edge in the surface direction of the portion that will become the fastening hole 29c.

[0098] The area outside the imaginary line 35 is relatively close to the outer peripheral edge 17b, and plastic flow toward the outer peripheral edge 17b is facilitated. Therefore, the waste holes 33 may be provided within this area, but at least a portion of the waste holes 33 must be located inside the imaginary line 35.

[0099] After the fastening surface portion 29 is formed, fastening holes 29c are formed by punching as shown in FIG. 10(D), and the gasket 25 that has been applied along the receiving surface 27a of the cover 17 and cured is fixed therein.

[0100] In manufacturing the recording device 1, the cover 17 to which the gasket 25 is attached is attached to the base 15 to close the space 3a of the housing 3 that accommodates the disk 5.

[0101] More specifically, an internal mechanism including the disk 5 is installed in the base 15. The cover 17 with the gasket 25 attached is placed opposite the opening of the base 15 in the thickness direction. At this time, the cover 17 and the base 15 are positioned so that the tip of the gasket 25 faces the receiving surface 21a of the base 15.

[0102] In this state, the cover 17 and the base 15 are brought close to each other, and the tip of the gasket 25 is brought into contact with the receiving surface 21 a of the base 15 .

[0103] When the cover 17 and the base 15 are brought even closer to each other, the gasket 25 on the receiving surface 27 a of the cover 17 is compressed between the receiving surface 21 a of the base 15 .

[0104] Then, the fastening surface 29b of the cover 17 is joined to the fastened surface 19a of the base 15. In this state, the outer peripheral edge of the cover 17 fits inside the edge wall 15b of the base 15. Furthermore, the compression of the gasket 25 is completed, and the gasket 25 reaches a predetermined compressed height. In this embodiment, because the fastening surface portion 29 is thinned, the gasket 25 can be compressed by that amount, and the compressed height of the gasket 25 can be reduced.

[0105] In this joined state, the bolts 23 are inserted into the fastening holes 29c of the fastening surface portions 29 to fasten them to the cover receiving portions 19 of the base 15. At this time, in this embodiment, since the parallelism of the fastening surface portions 29 is small, the bolts 23 can be used to perform fastening more reliably.

[0106] In this way, by using the cover 17 of this embodiment, it is possible to obtain a recording device 1 in which the internal mechanism including the disk for recording and reading information is installed on the base 15.

[0107] In this embodiment, the dimension of the cover 17 in the thickness direction is reduced, so that the dimension of the recording device 1 as a whole in the thickness direction can be reduced. [Example]

[0108] 12(A) to 12(C) are schematic cross-sectional views showing a method for manufacturing a cover according to Example 2 of the present invention. Note that Example 2 has the same basic configuration as Example 1, and corresponding components are designated by the same reference numerals and redundant explanations will be omitted.

[0109] In the cover 17 of this embodiment, the fastening surface portion 29 is formed before the step portion 31 is formed.

[0110] 12(A), the fastening surface portion 29 is formed after the formation of the dummy holes 33. In this embodiment, the fastening surface portion 29 is formed by crushing the outer periphery 17a of the plate-shaped cover semifinished product 41 having the dummy holes 33, together with the portion that will become the fastening surface portion 29 as part of the outer periphery 17a. This crushing can be performed by pressing using an upper mold 47 having a planar shape larger than the fastening surface portion 29.

[0111] Since the sanitary holes 33 are formed before the step portion 31 is formed, plastic flow can be permitted even if they are formed further inward in the surface direction than the step portion 31. In this embodiment, the sanitary holes 33 are provided in the other portion 17c of the outer circumferential portion 17a. The position of the sanitary holes 33 may be set appropriately depending on the size of the upper mold 47, the amount of crushing, etc. The size of the upper mold 47 may be the same as the portion that becomes the fastening surface portion 29.

[0112] After the fastening surface portion 29 is formed, the step portion 31 is formed by using the upper mold 43 and the lower mold 45 in the same manner as in the first embodiment, as shown in FIG. 12(B).

[0113] After the step portion 31 is formed in this way, as shown in FIG. 12(C), fastening holes 29c are formed in the fastening surface portion 29 by punching in the same manner as in the first embodiment.

[0114] In Example 2, the fastening surface portion 29 is formed before the step portion 31 is formed, so that the fastening surface portion 29 can be easily thinned. Also, in Example 2, the portion that will become the fastening surface portion 29 and its surroundings are crushed, so that the fastening surface portion 29 can be easily and reliably thinned. Furthermore, in Example 2, the position of the waste hole 33 can be freely set as long as it is outside the gasket receiving portion 27 and inside the imaginary line 35. In addition, Example 2 can also achieve the same effects as Example 1. [Example]

[0115] 13(A) to 13(C) are schematic cross-sectional views showing a method for manufacturing a cover according to Example 3 of the present invention. Fig. 13 is a schematic plan view showing a portion that will become a fastening surface portion of a semi-finished cover of Example 3 and its surroundings. Note that Example 3 has the same basic configuration as Example 1, and corresponding configurations are assigned the same reference numerals and redundant explanations will be omitted.

[0116] In this embodiment, before forming the fastening surface portion 29 and the step portion 31, a portion that will become a contour region 29e along the contour 29d of the fastening surface portion 29 is crushed in advance. That is, as shown in Fig. 13(A), the portion of the semi-finished cover 41 that has the discard hole 33 formed therein that is to be crushed in advance is pressed against a flat lower die 51 by an upper die 49 that has the same planar shape as the portion of the semi-finished cover 41.

[0117] The contour region 29e of the fastening surface portion 29 refers to a band-shaped region extending outward in the planar direction from the contour 29d of the fastening surface portion 29. The area to be crushed first is part or all of the portion that will become this contour region 29e. In this embodiment, waste holes 33 are provided as in FIG. 7, and at least the portion of the portion that will become the contour region 29e that does not have waste holes 33 on the inner side in the planar direction is crushed first. In this embodiment, the portion that will become the step portion 31 located on the outer side in the planar direction of the contour region 29e is also crushed first, along with the contour region 29e.

[0118] After the preliminary crushing, the step portion 31 and the fastening surface portion 29 are formed as shown in Figures 13(B) and (C). The step portion 31 and the fastening surface portion 29 are formed in the same manner as in Example 1. Note that, as in Example 2, the step portion 31 may be formed after the fastening surface portion 29 is formed.

[0119] When forming the fastening surface portion 29, plastic flow is unlikely to occur in the portion that will become the contour region 29e adjacent to the waste hole 33, but by crushing this portion in advance, it is possible to obtain a flat fastening surface portion 29 with a small value of parallelism. In addition, the third embodiment can also achieve the same effects as the first embodiment. [Example]

[0120] 14(A) to 14(C) are schematic plan views showing a method for manufacturing a cover according to Example 4 of the present invention. Note that Example 4 has the same basic configuration as Example 1, and the same reference numerals are used to designate corresponding components, and redundant explanations will be omitted.

[0121] In this embodiment, as shown in Fig. 14(A), a waste hole 33 is formed within the range of the portion that will become the fastening hole 29c. Then, as shown in Fig. 14(B), after forming the step portion 31 and the fastening surface portion 29, the waste hole 33 is removed and the fastening hole 29c is formed by overlapping it, as shown in Fig. 14(C).

[0122] In the fourth embodiment, the same effects as those in the first embodiment can be achieved. [Example]

[0123] 15 is a schematic cross-sectional view showing a method for manufacturing a cover according to Example 5 of the present invention. Note that Example 5 has the same basic configuration as Example 1, and the same reference numerals are used to designate corresponding components, and redundant explanations will be omitted.

[0124] In this embodiment, after the fastening surface portion 29 is formed, the raised portion 29g of the contour region 29e along the contour 29d of the fastening surface portion 29 is removed to reduce the value of the parallelism of the contour region 29e.

[0125] The fastening surface portion 29 is formed after the step portion 31 is formed, as in the first embodiment. However, the fastening surface portion 29 may be formed before the step portion 31 is formed.

[0126] The raised portion 29g of the contour region 29e is removed by laser irradiation. However, the raised portion 29g of the contour region 29e may also be removed by cutting. The raised portion 29g refers to a portion of the bolt receiving surface 29a that is raised higher than the other portions of the fastening surface portion 29 and has a higher parallelism value.

[0127] When irradiating the laser, the raised portion 29g is identified using, for example, a laser displacement meter. The laser is irradiated onto the identified raised portion 29g while adjusting the output. By removing the raised portion 29g in this manner, the parallelism value of the fastening surface portion 29 can be reduced.

[0128] In addition, the fifth embodiment can also achieve the same effects as the first embodiment. [Explanation of symbols]

[0129] 1. Recording device 5. Disk (recording medium) 11 Tape film (recording medium) 15 base 17 Cover 17a outer periphery 17b outer edge 23 Bolts (fasteners) 25 Gasket 27 Gasket receiving part 29 Fastening surface part 29c fastening hole 29d Contour 29e Contour Area 29g raised part 31 Step 33 Dump hole 35 Virtual Line 41 Cover semi-finished products

Claims

1. A method for manufacturing a cover that is attached to a base of a recording device by fastening, comprising: A waste hole is provided on the outer periphery of the plate-shaped cover semi-finished product, a part of the outer periphery of the semi-finished cover is crushed in a thickness direction to form the fastening surface portion for fastening, the fastening surface portion being relatively thin while allowing plastic flow during the crushing by the discarded hole; Before or after forming the fastening surface portion, a step portion is formed that surrounds the fastening surface portion relative to a part of the outer peripheral edge of the outer peripheral portion and biases the fastening surface portion in a thickness direction; A fastening hole is provided on the fastening surface portion, The waste hole is parallel to the outer peripheral edge and at least a portion thereof is located inside an imaginary line tangent to an outer edge in a surface direction of the portion to be the fastening hole. How the cover is manufactured.

2. A method for manufacturing the cover of claim 1, The fastening surface portion is formed by crushing a part of the outer circumferential portion and its surroundings before the step portion is formed. How the cover is manufactured.

3. A method for manufacturing the cover of claim 1 or 2, a portion that will become a contour region along the contour of the fastening surface portion is crushed in advance before the fastening surface portion and the step portion are formed; How the cover is manufactured.

4. A method for manufacturing the cover according to any one of claims 1 to 3, After forming the fastening surface portion, a raised portion of a contour region along the contour of the fastening surface portion is removed to reduce the value of the parallelism of the contour region. How the cover is manufactured.

5. A method for manufacturing the cover according to any one of claims 1 to 4, The waste hole is formed so that a portion of the waste hole is located in at least one of the portion that will become the step portion and the portion that will become the fastening surface portion. How the cover is manufactured.

6. A method for manufacturing the cover of claim 5, The waste hole is located within the range of the portion that becomes the fastening surface portion. How the cover is manufactured.

7. A method for manufacturing the cover of claim 5, The waste hole is located within a range of the portion that becomes the step portion. How the cover is manufactured.

8. A method for manufacturing a cover according to any one of claims 1 to 7, The waste hole has a shape that follows the contour of the fastening surface portion. How the cover is manufactured.

9. A method for manufacturing the cover of claim 5, The waste hole is located within the range of the portion that will become the fastening hole. How the cover is manufactured.

10. A method for manufacturing the cover according to any one of claims 1 to 9, a gasket receiving portion for receiving a gasket on an inner side in the surface direction of a portion that becomes the step portion in the outer periphery of the cover semi-finished product, The waste hole is provided on the outer side of the gasket receiving portion in the surface direction. How the cover is manufactured.

11. A plate-shaped cover that is fastened to the base of the recording device, a fastening surface portion for fastening formed relatively thin by crushing a part of an outer periphery in a thickness direction; a fastening hole provided on the fastening surface portion; a step portion that surrounds the fastening surface portion relative to a part of an outer peripheral edge of the outer peripheral portion and biases the fastening surface portion in the thickness direction; a blind hole that is parallel to the outer peripheral edge and has at least a portion located inside a virtual line that is tangent to the outer edge in the surface direction of the fastening hole, and that allows plastic flow when the fastening surface portion is crushed; Cover with.

Images