U.S. patent application number 15/459524 was filed with the patent office on 2018-02-08 for disk device with housing accommodating rotatable disk.
The applicant listed for this patent is Kabushiki Kaisha Toshiba. Invention is credited to Takuma Kido, Makoto Okamoto, Yasutaka Sasaki.
Application Number | 20180040352 15/459524 |
Document ID | / |
Family ID | 61027308 |
Filed Date | 2018-02-08 |
United States Patent
Application |
20180040352 |
Kind Code |
A1 |
Okamoto; Makoto ; et
al. |
February 8, 2018 |
DISK DEVICE WITH HOUSING ACCOMMODATING ROTATABLE DISK
Abstract
According to one embodiment, a disk device includes a housing
and a sealing board fixed to a base of the housing. The base
includes a through-hole and an installation surface formed around
the through-hole. One of a first principal surface of the sealing
board and the installation surface includes a projection formed
therein. The sealing board is fixed to the installation surface by
an adhesive material provided on an outer side of the projection
with respect to the through-hole with the first principal surface
or the installation surface abutting against the projection.
Inventors: |
Okamoto; Makoto; (Kodaira
Tokyo, JP) ; Kido; Takuma; (Mitaka Tokyo, JP)
; Sasaki; Yasutaka; (Yokohama Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kabushiki Kaisha Toshiba |
Tokyo |
|
JP |
|
|
Family ID: |
61027308 |
Appl. No.: |
15/459524 |
Filed: |
March 15, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62371302 |
Aug 5, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G11B 33/122 20130101;
G11B 33/027 20130101; G11B 33/126 20130101; G11B 33/1466
20130101 |
International
Class: |
G11B 33/14 20060101
G11B033/14; G11B 33/12 20060101 G11B033/12; G11B 33/02 20060101
G11B033/02 |
Claims
1. A disk device comprising: a rotatable disk recording medium; a
head which processes data on the recording medium; a housing
comprising a base accommodating the recording medium and the head
and a cover joined to the base, the base comprising a through-hole
and an installation surface formed around the through-hole; and a
sealing board fixed to the installation surface of the base to
block the through-hole, the sealing board comprising a first
principal surface, a second principal surface on an opposite side
to the first principal surface, and a conduction path electrically
connecting the first principal surface and the second principal
surface to each other, one of the first principal surface of the
sealing board and the installation surface including a projection
formed therein, and the sealing board being fixed to the
installation surface by an adhesive material including at least a
brazing material, provided on an outer side of the projection,
between the first principal surface and the installation surface,
with the other of the first principal surface and the installation
surface abutting against the projection, wherein the base includes
a stepped portion projecting from the installation surface and
separating from the projection, and a height of the stepped portion
is less than a height of the projection.
2. The disk device of claim 1, wherein the projection is formed on
the installation surface and includes a rib provided to surround
the through-hole.
3. The disk device of claim 2, wherein the rib includes an inner
circumferential surface extending along an inner circumferential
surface of the through-hole.
4. The disk device of claim 2, wherein the adhesive material
includes a solder.
5. The disk device of claim 4, wherein the projection includes a
contact surface in contact with the sealing board and the base
comprises a plated layer formed on the installation surface except
for the contact surface of the projection.
6. The disk device of claim 1, wherein the projection includes a
rib provided on the first principal surface of the sealing
board.
7. The disk device of claim 6, wherein the adhesive material
includes an adhesive or a gluing agent.
8. The disk device of claim 1, wherein the sealing board is formed
of a resin and the projection is formed from a resist layer
provided on the first principal surface.
9. The disk device of claim 1, wherein the sealing board is formed
of glass or ceramic.
10. The disk device of claim 1, wherein the base includes a
plurality of pins provided to stand on the installation surface,
and the sealing board includes a plurality of holes in which the
plurality of pins are inserted, respectively.
11. The disk device of claim 10, wherein the plurality of pins
include two pins respectively provided to stand at diagonally
opposite two corners of the installation surface.
12. (canceled)
13. The disk device of claim 1, wherein the stepped portion is
provided at each of diagonally opposite two corners of the
installation surface.
14. The disk device of claim 13, wherein the base includes two pins
provided to stand on the stepped portions, and the sealing board
includes a plurality of holes in which the pins are inserted.
15. The disk device of claim 1, further comprising: a first
connector mounted on the first principal surface, and a second
connector mounted on the second principal surface of the sealing
board to oppose the first connector, and electrically connected to
the first connector through the conduction path, wherein the first
connector is exposed to an inside of the housing through the
through-hole and the second connector is exposed to an external
surface side of the housing.
16. The disk device of claim 1, wherein the housing is enclosed
with a gas of a density lower than that of air.
17. A disk device comprising: a rotatable disk recording medium; a
head which processes data on the recording medium; a housing
comprising a base accommodating the recording medium and the head
and a cover joined to the base, the base comprising a through-hole
and an installation surface formed around the through-hole; and a
sealing board fixed to the installation surface of the base to
block the through-hole, the sealing board comprising a first
principal surface, a second principal surface on an opposite side
to the first principal surface, and a conduction path electrically
connecting the first principal surface and the second principal
surface to each other, a projection formed on the installation
surface and including a rib provided to surround the through-hole,
and the sealing board being fixed to the installation surface by an
adhesive material including a solder, provided on an outer side of
the projection, between the first principal surface and the
installation surface, with the other of the first principal surface
and the installation surface abutting against the projection, the
projection including a contact surface in contact with the sealing
board and the base comprising a plated layer formed on the
installation surface except for the contact surface of the
projection.
18. The disk device of claim 17, wherein the rib includes an inner
circumferential surface extending along an inner circumferential
surface of the through-hole.
19. The disk device of claim 17, wherein the base includes a
stepped portion projecting from the installation surface and
separate from the projection, and a height of the stepped portion
is less than a height of the projection.
20. The disk device of claim 17, wherein the housing is enclosed
with a gas of a density lower than that of air.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/371,302, filed Aug. 5, 2016, the entire contents
of which are incorporated herein by reference.
FIELD
[0002] Embodiments described herein relate generally to a disk
device.
BACKGROUND
[0003] As a disk device, a magnetic disk drive includes a housing
having a base and a top cover, and a rotatable magnetic disk and an
actuator supporting thereon magnetic heads are arranged in the
housing. As a method of improving the performance of the disk
drive, a method of reducing the rotational resistance of the
magnetic disk and the magnetic head by filling the housing with a
low-density gas such as helium or the like, and closely sealing the
housing is proposed.
[0004] In such a magnetic disk drive, the top cover is laser-welded
onto the base of the housing thereby forming a hermetically-sealed
housing and increasing the airtightness of the housing. This laser
welding is carried out along the entire outer circumference of the
top cover. Further, in order to transmit an electrical signal of
the magnetic head provided inside the housing to a control circuit
board provided outside the device, a connector penetrating the
bottom wall of the housing is provided. In such a gas-filled
magnetic disk drive described above, it is desirable that a
hermetic connector be used as the aforementioned connector in order
to maintain the airtightness of the housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a perspective view showing an external view of a
hard disk drive (HDD) according to a first embodiment.
[0006] FIG. 2 is an exploded perspective view of the HDD according
to the first embodiment.
[0007] FIG. 3 is a perspective view showing a base of a housing of
the HDD.
[0008] FIG. 4 is a perspective view showing the back surface side
of the base.
[0009] FIG. 5 is an exploded perspective view showing a connector
installation part and a connector unit of the base.
[0010] FIG. 6 is a cross-sectional view of the connector
installation part and the connector unit taken along line VI-VI of
FIG. 4.
[0011] FIG. 7 is an exploded perspective view showing a connector
installation part and a connector unit of a base of an HDD
according to a second embodiment.
[0012] FIG. 8 is a perspective view showing the first principal
surface side of a connector unit.
[0013] FIG. 9 is a cross-sectional view of the connector
installation part and the connector unit of the base of the HDD
according to the second embodiment.
[0014] FIG. 10 is a cross-sectional view showing a connector
installation part and a connector unit of an HDD according to a
first modification example.
[0015] FIG. 11 is a cross-sectional view of a connector
installation part and a connector unit of a base of an HDD
according to a third embodiment.
[0016] FIG. 12 is a perspective view showing a sealing board of the
connector unit.
[0017] FIG. 13 is a perspective view showing a sealing board of an
HDD according to a second modification example.
[0018] FIG. 14 is a perspective view showing a connector
installation part of an HDD according to a third modification
example.
DETAILED DESCRIPTION
[0019] Various embodiments will be described hereinafter with
reference to the accompanying drawings. In general, according to
one embodiment, a disk device comprises a rotatable disk recording
medium; a head which processes data on the recording medium; a
housing comprising a base accommodating the recording medium and
the head and a cover joined to the base, the base comprising a
through-hole and an installation surface formed around the
through-hole; and a sealing board fixed to the installation surface
of the base to block the through-hole, the sealing board comprising
a first principal surface, a second principal surface on an
opposite side to the first principal surface, and a conduction path
electrically connecting the first principal surface and the second
principal surface to each other. One of the first principal surface
of the sealing board and the installation surface includes a
projection formed therein, and the sealing board is fixed to the
installation surface by an adhesive material including at least a
brazing material, provided on an outer side of the projection,
between the first principal surface and the installation surface,
with the other of the first principal surface and the installation
surface abutting against the projection.
[0020] Hereinafter, hard disk drives (HDDs) according to
embodiments will be descried in detail as disk devices.
First Embodiment
[0021] FIG. 1 is a perspective view showing an external view of an
HDD according to a first embodiment, and FIG. 2 is an exploded
perspective view showing an internal structure of the HDD.
[0022] As shown in FIG. 1 and FIG. 2, the HDD includes a flat and
substantially rectangular housing 10.
[0023] This housing 10 comprises a rectangular box-shaped base 12
opened at a top surface thereof, inner cover 14 screwed onto the
base 12 by a plurality of screws 13 to thereby close the upper-end
opening of the base 12, and outer cover (top cover) 16 placed on
top of the inner cover 14, and a peripheral part of which is welded
onto the base 12. The base 12 includes a rectangular bottom wall
12a opposed to the inner cover 14 with a gap held between them, and
side wall 12b provided to stand along the periphery of the bottom
wall 12a, and is integrally formed of, for example, aluminum. The
side wall 12b includes a pair of long-side walls opposed to each
other and a pair of short-side walls opposed to each other. A
substantially rectangular frame-shaped fixing rib 12c is provided
on the upper end surface of the side wall 12b in a projecting
manner.
[0024] The inner cover 14 is formed of stainless steel into a
rectangular plate. The inner cover 14 is screwed onto the top
surface of the side wall 12b at a peripheral part thereof by means
of screws 13 to thereby be fixed to the inside of the fixed rib
12c. The outer cover 16 is formed of, for example, aluminum into a
rectangular plate-like shape. The outer cover 16 is formed in a
planar size slightly greater than the inner cover 14. The outer
cover 16 is welded onto the fixed rib 12c of the base 12 at the
entire peripheral part thereof and is hermetically fixed. In each
of the inner cover 14 and the outer cover 16, vents 46 and 48
through which the inside of the housing 10 communicates with the
outside are formed, respectively. The air inside the housing 10 is
exhausted through the vents 46 and 48 and, furthermore a
low-density gas (inert gas), for example, helium having a density
lower than that of air is infused through these vents 46 and 48.
For example, a sealant (an adhesive material including at least a
brazing material) 52 is stuck on the outer surface of the outer
cover 16 so as to close the vent 48.
[0025] As shown in FIG. 2, a plurality of magnetic disks 18 serving
as recording mediums, and a spindle motor 20 serving as a drive
section configured to support and rotate the magnetic disks 18 are
provided in the housing 10. The spindle motor 20 is arranged on the
bottom wall 12a. Each of the magnetic disks 18 is formed into a
size of, for example, 88.9 mm (3.5 inches) in diameter, and
includes a magnetic recording layer in the top surface and/or in
the undersurface thereof. Each of the magnetic disks 18 is fitted
on a hub (not shown) of the spindle motor 20 coaxially with each
other, and is clamped by a clamp spring to thereby be fixed to the
hub. Each of the magnetic disks 18 is supported in a state where
the disk 18 is positioned parallel to the bottom wall 12a of the
base 12. Each of the magnetic disks 18 is rotated by the spindle
motor 20 at a predetermined rotational speed.
[0026] It should be noted that as shown in FIG. 2, although, for
example, five magnetic disks 18 are accommodated in the housing 10
in this embodiment, the number of the magnetic disks 18 is not
limited to this. Further, a single magnetic disk 18 may be
accommodated in the housing 10.
[0027] In the housing 10, a plurality of magnetic heads 32
configured to carry out recording/reproduction of information
on/from the magnetic disks 18, and a head stack assembly (actuator)
22 configured to support these magnetic heads 32 to freely move the
magnetic heads 32 with respect to the magnetic disks 18 are
provided. Further, in the housing 10, a voice coil motor
(hereinafter referred to as a VCM) 24 configured to rotate and
position the head stack assembly 22, ramp loading mechanism 25
configured to retain the magnetic head 32 at an unloading position
separate from the magnetic disk 18 when the magnetic head 32 has
moved to the outermost circumference of the magnetic disk 18, and
board unit 21 on which electronic components such as a conversion
connector (third connector) 52, and the like are mounted are
provided. The board unit 21 is constituted of a flexible printed
circuit (FPC), and this FPC is electrically connected to the
magnetic heads 32 and the voice coil of the VCM 24 through a relay
FPC on the head stack assembly 22.
[0028] The head stack assembly 22 includes a rotatable bearing unit
28, a plurality of arms 30 extending from the bearing unit 28, and
suspensions 34 extending from the arms 30, and the magnetic head 32
is supported on a distal end part of each suspension 34.
[0029] A control circuit board 54 to be described later is screwed
onto an outer surface of the bottom wall 12a of the base 12. The
control circuit board 54 controls the operation of the spindle
motor 20, and controls the operations of the VCM 24 and the
magnetic heads 32 through the board unit 21.
[0030] FIG. 3 is a perspective view showing the base 12 of the
housing 10, in a state where the constituent elements are removed
therefrom, FIG. 4 is a perspective view showing the back surface
side of the housing and the control circuit board, FIG. 5 is an
exploded perspective view showing a connector installation part and
a connector unit of the base, and FIG. 6 is a cross-sectional view
of the connector installation part and the connector unit taken
along line VI-VI of FIG. 4.
[0031] As shown in FIG. 3 and FIG. 4, in the bottom wall 12a of the
base 12, for example, a rectangular through-hole (open hole) 58 is
formed at an end part of the base 12 near one short side. The
through-hole 58 is opened to the inner surface and the outer
surface (rear surface) of the bottom wall 12a. Further, a first
connector 62a of the connector unit 60 is attached to or inserted
in the through-hole 58.
[0032] As shown in FIG. 5 and FIG. 6, in the rear surface (outer
surface) of the bottom wall 12a, a substantially rectangular
installation recess 70 is formed in the area including the
through-hole 58. The bottom face of the recess 70 constitutes an
installation surface 72 positioned around the through-hole 58. An
annular, for example, a rectangular frame-shaped rib (projection)
74 surrounding the periphery of the through-hole 58 is provided on
the installation surface 72 in a projecting manner. The inner
circumferential surface of the rib 74 is flush with the inner
circumferential surface of the through-hole 58. The rib 74 has a
constant projection height (for example, 0.5 mm) and a constant
width (for example, 1 mm) throughout the entire circumference
thereof and, furthermore, the end face (contact surface) 74a of the
rib 74 is formed flat.
[0033] A positioning pin 76 is provided at each of two corners
opposed to each other in a diagonal direction of the installation
surface 72 in a standing manner. The projection height of the
positioning pin 76 is made substantially identical to the depth of
the installation recess 70. It should be noted that the rib 74 and
the two positioning pins 76 are formed integral with the bottom
wall 12a of the base 12.
[0034] In this embodiment, a stepped portion 78 one step higher
than the installation surface 72 is formed at each of the two
corners opposed to each other in the diagonal direction of the
installation surface 72, and the positioning pins 76 are provided
at the stepped portions 78 in a standing manner. The height (step
height) of the stepped portion 78 is made lower than the height of
the rib 74. A plated layer, for example, a nickel-plated layer 80
is formed on the installation surface 72 except the end face 74a of
the rib 74.
[0035] As shown in FIG. 5 and FIG. 6, the connector unit 60
includes a sealing board 64, and a first connector 62a and a second
connector 62b mounted on this sealing board. The sealing board 64
is formed into a substantially rectangular shape corresponding to
the installation recess 70 of the base 12, and is formed in a
planar size slightly smaller than the installation recess 70. The
sealing board 64 is constituted of, for example, a multi-layered
circuit board formed by laminating a number of printed circuit
boards. The sealing board 64 has a flat first principal surface 64a
and a flat second principal surface 64b on the opposite side of the
first principal surface 64a.
[0036] The first connector 62a is mounted on a substantially
central part of the first principal surface 64a. The second
connector 62b is mounted on a substantially central part of the
second principal surface 64b, and is opposed to the first connector
62a. The first connector 62a and the second connector 62b are
electrically connected to each other through conductive paths each
of which is formed of a conductive layer or a through-hole formed
in the sealing board 64.
[0037] A positioning hole 66 is formed at each of two corners
opposed to each other in a diagonal direction of the sealing board
64. These positioning holes 66 are provided at positions
corresponding to the positioning pins 76 of the base 12, and each
of the positioning holes 66 is formed so that the positioning pin
76 can be inserted therein.
[0038] As shown in FIG. 4 through FIG. 6, the connector unit 60 is
installed in the installation recess 70 formed in the bottom wall
12a of the base 12. That is, the sealing board 64 is installed in
the installation recess 70 in a state where the first principal
surface 64a and the first connector 62a are directed to the bottom
wall 12a side. Each of the pair of positioning pins 76 is inserted
in the corresponding positioning hole 66 of the sealing board 64.
Thereby, the sealing board 64 is positioned in terms of the
position in the plane direction with respect to the bottom wall
12a. The first principal surface 64a of the sealing board 64 is in
contact with the end face 74a of the rib 74. Thereby, the sealing
board 64 is positioned by the rib 74 in terms of the position in
the thickness direction thereof. The first connector 62a is
inserted in the through-hole 58 of the bottom wall 12a. The first
connector 62a is exposed to the inside of the base 12 through the
through-hole 58, and is accessible from the inside of the base
12.
[0039] At a part around the outside of the rib 74, a sealant
(brazing material) 82 is provided between the installation surface
72 of the installation recess 70 and the first principal surface
64a of the sealing board 64. The sealing board 64 is fixed to the
installation surface 72 by means of the sealant 82. In this
embodiment, as the sealant 82, for example, solder is used. In the
fixing and sealing process, as shown in FIG. 5, for example, a
solder sheet 82a formed into an annular shape is arranged on the
installation surface 72 around the outside of the rib 74. The
sealing board 64 is implemented in the installation recess 70, the
first principal surface 64a is made in contact with the end face
74a of the rib 74, and the first principal surface 64a is arranged
on the solder sheet 82a. In this state, the solder sheet 82a is
heated from the inner surface side or from the outer surface side
of the base 12, thereby melting the solder sheet 82a. The molten
solder wettedly spreads along the first principal surface 64a of
the sealing board 64 and the installation surface 72 to thereby
stick to the first principal surface 64a and the installation
surface 72. At this time, the molten solder is prevented from
flowing into the through-hole 58 by the rib 74. Furthermore, the
nickel-plated layer 80 is formed on the installation surface 72
except the end face 74a of the rib 74, and hence the wettability of
the molten solder on the installation surface 72 is improved. At
the same time, the molten solder is prevented from flowing into the
gap between the end face 74a of the rib 74 and the first principal
surface 64a of the sealing board 64. Further, in this embodiment,
the molten solder is restrained from excessively flowing to the
outside by the stepped portion 78 provided on the proximal end side
of each positioning pin 76. Thereby, most of the solder remains at
the part between the rib 74 and the stepped portions 78, and
sufficiently fills the space between the installation surface 72
and the first principal surface 64a therewith.
[0040] As shown in FIG. 6, the sealing board 64 is fixed to the
installation surface 72 of the base 12 by the sealant 82, and
covers the through-hole 58 of the base 12. At the same time, the
space between the first principal surface 64a of the sealing board
64 and the installation surface 72 is hermetically sealed with the
sealant 82. Thereby, the connector unit 60 hermetically seals the
through-hole 58 on the rear surface side of the base 12. The first
connector 62a of the connector unit 60 is inserted in the
through-hole 58, and is exposed to the inside of the base 12
through the through-hole 58. That is, the first connector 62a is
provided so that another connector can be connected to the first
connector 62a from inside the base 12. A third connector 52 of the
board unit 21 provided inside the base 12 is connected to the first
connector 62a of the connector unit 60.
[0041] The second connector 62b of the connector unit 60 is exposed
to the outer surface (rear surface) side of the base 12. As shown
in FIG. 4 and FIG. 6, the control circuit board 54 is arranged to
be opposed to the rear surface of the bottom wall 12a of the base
12, and is screwed onto the bottom wall 12a by means of a plurality
of screws. The control circuit board 54 is provided to cover the
connector unit 60. A fourth connector 56 is mounted on the control
circuit board 54. This fourth connector 56 is connected to the
second connector 62b of the connector unit 60. As described above,
the magnetic heads 32 and the voice coil of the VCM provided inside
the base 12 are electrically connected to the control circuit board
54 provided outside the base 12 through the relay FPC, board unit
21, third connector 52, connector unit 60, and fourth connector 56
in a state where the airtightness inside the housing 10 is
maintained by the connector unit 60.
[0042] According to the HDD associated with the first embodiment
configured as described above, in the fixation structure of the
connector unit 60, the annular rib (projection) 74 is provided on
the installation surface 72 around the through-hole 58, and the
sealing board 64 is arranged in a state where the first principal
surface 64a of the sealing board 64 is made in contact with the end
face 74a of the rib 74, whereby it is possible to position the
sealing board 64 in terms of the height position, i.e., the
position in the thickness direction of the sealing board 64 with
respect to the installation surface 72. Thereby, it is possible to
maintain the gap between the first principal surface 64a of the
sealing board 64 and the installation surface 72 constant, and
manage the thickness of the sealant 82 to be filled into this gap
constant. Further, it is possible by the rib 74 to prevent the
sealant 82 from flowing into the through-hole 58, and retain the
sealant 82 in the desired space. Furthermore, according to this
embodiment, the stepped portions 78 are provided on the
installation surface 72 on the outside of the rib 74. By virtue of
these stepped portions 78, it is possible to suppress the flow of
the sealant 82, and retain the sealant 82 in the desired space.
Therefore, according to this embodiment, it becomes possible to
reduce unnecessary spread and wetting of the sealant, and securely
seal the desired space with a minimum amount of the sealant.
[0043] Further, according to this embodiment, by inserting the
positioning pins provided on the installation surface 72 of the
base 12 in a standing manner in the positioning holes 66 of the
sealing board 64, the sealing board 64 is positioned in terms of
the position in the plane direction with respect to the base 12.
Accordingly, the in-plane positional accuracy of the first
connector 62a and the second connector 62b is improved. Further,
the influence of misalignment between the first connector 62a and
the second connector 62b is made less significant irrespectively of
the size of the first and second connectors 62a and 62b. Thereby,
the third connector 52 inside the housing 10 and the fourth
connector 56 outside the housing 10 can easily and stably be
connected to the first connector 62a and the second connector 62b,
respectively.
[0044] From the above description, according to the first
embodiment, it is possible to obtain a disk device which is
improved in the airtightness of the housing, and can easily be
connected to the connector or the control circuit board outside the
housing.
[0045] Next, an HDD according to another embodiment will be
described. It should be noted that in another embodiment to be
described in the following, parts identical to the aforementioned
first embodiment are denoted by reference symbols identical to the
first embodiment, their detailed descriptions are simplified or
omitted, and parts different from the first embodiment are mainly
described in detail.
Second Embodiment
[0046] FIG. 7 is an exploded perspective view showing a connector
installation part and a connector unit of a base of an HDD
according to a second embodiment. FIG. 8 is a perspective view
showing the first principal surface side of a connector unit. FIG.
9 is a cross-sectional view of the connector installation part and
the connector unit.
[0047] As shown in FIG. 7 and FIG. 8, according to the second
embodiment, an installation surface 72 of an installation recess 70
is formed flat, and an annular rib 74 serving as a projection is
provided on a first principal surface 64a of a sealing board 64. A
positioning pin 76 is provided at each of two corners opposed to
each other in a diagonal direction of the installation surface 72
in a standing manner. The projection height of the positioning pin
76 is made substantially identical to the depth of the installation
recess 70. The two positioning pins 76 are formed integral with a
bottom wall 12a of the base 12.
[0048] The connector unit 60 includes the sealing board 64, and a
first connector 62a and second connector 62b mounted on this
sealing board. The sealing board 64 is formed into a substantially
rectangular shape corresponding to the installation recess 70 of
the base 12, and is formed in a planar size slightly smaller than
the installation recess 70. The sealing board 64 is formed of, for
example, glass or ceramic. The sealing board 64 has a flat first
principal surface 64a and a flat second principal surface 64b on
the opposite side of the first principal surface 64a. The first
connector 62a is mounted on a substantially central part of the
first principal surface 64a. The second connector 62b is mounted on
a substantially central part of the second principal surface 64b,
and is opposed to the first connector 62a. The first connector 62a
and the second connector 62b are electrically connected to each
other through a plurality of conductive pins (conductive paths) 65
embedded in the sealing board 64.
[0049] An annular, for example, a rectangular frame-shaped rib
(projection) 74 surrounding the periphery of the first connector
62a is provided on the first principal surface 64a of the sealing
board 64 in a projecting manner. The rib 74 has a constant
projection height (for example, 0.1 mm) and a constant width (for
example, 0.5 mm) throughout the entire circumference thereof and,
furthermore, the end face (contact surface) 74a of the rib 74 is
formed flat. The rib 74 is formed of glass or ceramic and is formed
integral with the sealing board 64. A positioning hole 66 is formed
at each of two corners opposed to each other in a diagonal
direction of the sealing board 64. These positioning holes 66 are
provided at positions corresponding to the positioning pins 76 of
the base 12, and each of the positioning holes 66 is formed so that
the positioning pin 76 can be inserted therein.
[0050] As shown in FIG. 9, the connector unit 60 is implemented in
the installation recess 70 formed in the bottom wall 12a of the
base 12. The sealing board 64 is arranged in the installation
recess 70 in a state where the first principal surface 64a and the
first connector 62a are directed to the bottom wall 12a side. Each
of the pair of positioning pins 76 is inserted in the corresponding
positioning hole 66 of the sealing board 64. Thereby, the sealing
board 64 is positioned in terms of the position in the plane
direction with respect to the bottom wall 12a. Further, the sealing
board 64 is installed in the installation recess 70 in a state
where the end face 74a of the rib 74 is in contact with the
installation surface 72 of the installation recess 70. Thereby, the
sealing board 64 is positioned by the rib 74 in terms of the
position in the thickness direction thereof, and the first
principal surface 64a is opposed to the installation surface 72
with a gap corresponding to the height of the rib 74 held between
them. The first connector 62a is inserted in the through-hole 58 of
the bottom wall 12a. Thereby, the first connector 62 is exposed to
the inside of the base 12, and is accessible from the inside of the
base 12.
[0051] The space between the installation surface 72 of the
installation recess 70 and the first principal surface 64a of the
sealing board 64 is filled with a sealant 82 around the outside of
the rib 74. According to this embodiment, as the sealant 82, a
resin adhesive or gluing agent may be used. The sealant 82 is
filled into the space between the first principal surface 64a of
the sealing board 64 and the installation surface 72 in a state
where the rib 74 of the sealing board 64 is pressed against the
installation surface 72, i.e., in a state where the rib 74 of the
sealing board 64 is made in contact with the installation surface
72. The sealing board 64 is fixed to the installation surface 72 by
means of the sealant 82. At the same time, the space between the
first principal surface 64a and the installation surface 72, and
the part around the through-hole 58 are sealed with the sealant
82.
[0052] As described above, the sealing board 64 of the connector
unit 60 is fixed to the installation surface 72 of the base 12 by
means of the sealant 82, and covers the through-hole 58 of the base
12. At the same time, the space between the first principal surface
64a of the sealing board 64 and the installation surface 72 is
hermetically sealed with the sealant 82. Thereby, the connector
unit 60 hermetically seals the through-hole 58 on the back surface
side of the base 12. The first connector 62a of the connector unit
60 is inserted in the through-hole 58, and is exposed to the inside
of the base 12 through this through-hole 58. A third connector 52
of a board unit 21 provided inside the base 12 is connected to the
first connector 62a of the connector unit 60. The second connector
of the connector unit 60 is exposed to the outer surface (back
surface) side of the base 12. A fourth connector 56 mounted on a
control circuit board 54 is connected to the second connector 62b
of the connector unit 60.
[0053] According to the HDD associated with the second embodiment
configured as described above, in the fixation structure of the
connector unit 60, the annular rib (projection) 74 is provided on
the first principal surface 64a of the sealing board 64 around the
first connector 62a, and the sealing board 64 is arranged in a
state where the end face 74a of the rib 74 is made in contact with
the installation surface 72 of the base 12, whereby it is possible
to position the sealing board 64 in terms of the height position,
i.e., the position in the thickness direction of the sealing board
64 with respect to the installation surface 72. Thereby, it is
possible to maintain the gap between the first principal surface
64a of the sealing board 64 and the installation surface 72
constant, and manage the thickness of the sealant 82 to be filled
into this gap constant. Further, it is possible by the rib 74 to
prevent the sealant 82 from flowing into the inside of the
through-hole 58, and retain the sealant 82 in the desired space.
Furthermore, according to this embodiment, the stepped portions 78
are provided on the installation surface 72 on the outside of the
rib 74. By virtue of these stepped portions 78, it is possible to
suppress the flow of the sealant 82, and retain the sealant 82 in
the desired space. Therefore, according to this embodiment, it
becomes possible to reduce unnecessary spread and wetting of the
sealant, and securely seal the desired space with a minimum amount
of the sealant.
[0054] Further, according to this embodiment, by inserting the
positioning pins provided on the installation surface 72 of the
base 12 in a standing manner in the positioning holes 66 of the
sealing board 64, the sealing board 64 is positioned in terms of
the position in the plane direction with respect to the base 12.
Accordingly, the in-plane positional accuracy of the first
connector 62a and the second connector 62b is improved. Further,
the influence of misalignment between the first connector 62a and
the second connector 62b is made less significant irrespectively of
the size of the first and second connectors 62a and 62b. Thereby,
it becomes possible to easily and stably connect the third
connector 52 inside the housing 10 and the fourth connector 56
outside the housing to the first connector 62a and the second
connector 62b, respectively.
[0055] From the above description, according to the second
embodiment too, it is possible to obtain a disk device which is
improved in the airtightness of the housing, and can easily be
connected to the connector or the control circuit board outside the
housing.
[0056] It should be noted that in the second embodiment, the
material of the sealing board 64 of the connector unit 60 is not
limited to glass or ceramic, and a multi-layered circuit board
similar to the first embodiment may be used. In this case, the rib
(projection) 74 of the sealing board 64 can be formed of, for
example, a resist layer formed on the surface of the circuit board.
As the sealant 82, brazing material may be used.
[0057] Further, the configuration of the rib 74 of the sealing
board 64 is not limited to the configuration in which the rib 74 is
provided at a position in line with the inner circumferential
surface of the through-hole 58 of the base 12, and the rib 74 may
be provided at a position separate from the through-hole 58.
[0058] FIG. 10 is a cross-sectional view showing a connector
installation part and a connector unit of an HDD according to a
first modification example. As shown in this view, according to the
first modification example, an annular rib 74 of a sealing board 64
is provided at a position outwardly separate from an inner
circumferential surface of a through-hole 58 of a base 12. Outside
and inside the rib 74, a sealant 82 is filled into the space
between a first principal surface 64a of the sealing board 64 and
an installation surface 72. When an adhesive or a gluing agent
having no electrical conductivity is used as the sealant 82, even
if the sealant flows into the through-hole 58 of the base, no
problem of electrical continuity is caused. Accordingly, at the
part between the rib 74 and the through-hole 58, the sealant 82 can
be filled into the space between the first principal surface 64a of
the sealing board 64 and the installation surface 72.
Third Embodiment
[0059] FIG. 11 is a cross-sectional view of a connector
installation part and a connector unit of a base of an HDD
according to a third embodiment, and FIG. 12 is a perspective view
showing a sealing board of the connector unit.
[0060] As shown in FIG. 11 and FIG. 12, according to the third
embodiment, the connector unit 60 includes only the sealing board
64, and first and second connectors are omitted. The sealing board
64 hermetically seals a through-hole 58 of the base 12, and
functions also as a conductive member configured to electrically
connect a conversion connector (third connector) 52 inside the base
12 and a fourth connector 56 on a printed circuit board 54 provided
outside the housing to each other. Thereby, the so-called one piece
connection structure configured to directly connect the conversion
connector (third connector) 52 and the fourth connector 56 to each
other can be obtained.
[0061] The structure of the instrumentation part in a bottom wall
12a of the base 12 is identical to the aforementioned first
embodiment. That is, in the rear surface (outer surface) of the
bottom wall 12a, a substantially rectangular installation recess 70
is formed in the area including a through-hole 58. The bottom face
of the installation recess 70 constitutes an installation surface
72 positioned around the through-hole 58. An annular, for example,
a rectangular frame-shaped rib (projection) 74 surrounding the
periphery of the through-hole 58 is provided on the installation
surface 72 in a projecting manner. The inner circumferential
surface of the rib 74 is arranged flush with the inner
circumferential surface of the through-hole 58. A positioning pin
76 is provided at each of two corners opposed to each other in a
diagonal direction of the installation surface 72 in a standing
manner. The projection height of the positioning pin 76 is made
substantially identical to the depth of the installation recess 70.
It should be noted that the rib 74 and the two positioning pins 76
are formed integral with the bottom wall 12a of the base 12. A
plated layer, for example, a nickel-plated layer 80 is formed on
the installation surface 72 except the end face 74a of the rib
74.
[0062] As shown in FIG. 11 and FIG. 12, the connector unit 60
includes a sealing board 64. The sealing board 64 is formed into a
substantially rectangular shape corresponding to the installation
recess 70 of the base 12, and is formed in a planar size slightly
smaller than the installation recess 70. The sealing board 64 is
constituted of, for example, a multi-layered circuit board formed
by laminating a number of printed circuit boards. The sealing board
64 has a flat first principal surface 64a and a flat second
principal surface 64b on the opposite side of the first principal
surface 64a.
[0063] A plurality of conductive pads 86a are provided at a
substantially central part of the first principal surface 64a.
These conductive pads 86a are provided to be arranged in two rows
along the longitudinal direction of the first principal surface
64a. On the first principal surface 64a, an annular or a
track-shaped plated layer, for example, a gold-plated layer 88 is
formed around the conductive pads 86a.
[0064] A plurality of conductive pads 86b are provided at a
substantially central part of the second principal surface 64b of
the sealing board 64. These conductive pads 86b are provided to be
arranged in two rows along the longitudinal direction of the second
principal surface 64b. Each of the conductive pads 86b and a
corresponding conductive pad 86a on the first principal surface 64a
side are electrically connected to each other through a conductive
path constituted of a conductive layer, through-hole or the like
formed in the sealing board 64.
[0065] A positioning hole 66 is formed at each of two corners
opposed to each other in a diagonal direction of the sealing board
64. These positioning holes 66 are provided at positions
corresponding to the positioning pins 76 of the base 12, and each
of the positioning holes 66 is formed so that the positioning pin
76 can be inserted therein.
[0066] As shown in FIG. 11, the sealing board 64 is installed in
the installation recess 70 formed in the bottom wall 12a of the
base 12, and seals the through-hole 58. That is, the sealing board
64 is implemented in the installation recess 70 in a state where
the first principal surface 64a is directed to the bottom wall 12a
side. Each of the pair of positioning pins 76 is inserted in the
corresponding positioning hole 66 of the sealing board 64. Thereby,
the sealing board 64 is positioned in terms of the position in the
plane direction with respect to the bottom wall 12a. Further, the
first principal surface 64a of the sealing board 64 is in contact
with the end face 74a of the rib 74. Thereby, the sealing board 64
is positioned by the rib 74 in terms of the position in the
thickness direction thereof.
[0067] Around the outside of the rib 74, a sealant 82 is filled
into the space between the installation surface 72 of the
installation recess 70 and the first principal surface 64a of the
sealing board 64. The sealing board 64 is fixed to the installation
surface 72 by the sealant 82. In this embodiment, as the sealant
82, for example, solder is used. In the fixing and sealing process,
for example, a solder sheet formed into an annular shape is
arranged on the installation surface 72 around the outside of the
rib 74. The sealing board 64 is arranged in the installation recess
70, the first principal surface 64a is made in contact with the end
face 74a of the rib 74, and the first principal surface 64a is
arranged on top of the solder sheet. In this state, the solder
sheet is heated from the inner surface side or from the outer
surface side of the base 12, thereby melting the solder sheet. The
molten solder spreads along the first principal surface 64a of the
sealing board 64 and the installation surface 72 in a wetting
manner to thereby stick to the first principal surface 64a and the
installation surface 72. At this time, the solder is prevented from
flowing into the inside of the through-hole 58 by the rib 74.
Moreover, the nickel-plated layer 80 is formed on the installation
surface 72 except the end face 74a of the rib 74, furthermore, the
gold-plated layer 88 is formed on the first principal surface 64a
of the sealing board 64, and hence the wettability of the molten
solder on the installation surface 72 and on the first principal
surface 64a is improved. At the same time, the molten solder is
prevented from flowing into the gap between the end face 74a of the
rib 74 and the first principal surface 64a of the sealing board 64.
Further, in this embodiment, the molten solder is restrained from
excessively flowing to the outside by the stepped portion 78
provided on the proximal end side of each positioning pin 76.
Thereby, most of the solder remains at the part between the rib 74
and the stepped portions 78, and sufficiently fills the space
between the installation surface 72 and the first principal surface
64a therewith. The sealing board 64 is fixed to the installation
surface 72 of the base 12 by the sealant 82, and covers the
through-hole 58 of the base 12. At the same time, the space between
the first principal surface 64a of the sealing board 64 and the
installation surface 72 is hermetically sealed with the sealant 82.
Thereby, the sealing board 64 of the connector unit 60 hermetically
seals the through-hole 58 on the back surface side of the base 12.
The conductive pads 86a of the sealing board 64 are exposed to the
inside of the base 12 through the through-hole 58. The third
connector 52 of a board unit 21 provided inside the base 12 is
connected to the conductive pads 86a.
[0068] The conductive pads 86b on the second principal surface 64b
side of the sealing board 64 are exposed to the outer surface (rear
surface) side of the base 12.
[0069] The control circuit board 54 is arranged to be opposed to
the back surface of the bottom wall 12a of the base 12. A fourth
connector 56 is mounted on the control circuit board 54. This
fourth connector 56 is connected to the conductive pads 86b of the
sealing board 64. Thereby, the fourth connector 56 is electrically
connected to the third connector inside the base 12 through the
conductive pads 86a and 86b, and the conductive paths of the
sealing board 64.
[0070] As described above, the magnetic heads and the voice coil of
the VCM provided inside the base 12 are electrically connected to
the control circuit board 54 provided on the outside of the base 12
through the relay FPC, board unit 21, third connector 52, sealing
board 64, and fourth connector 56 in a state where the airtightness
inside the housing 10 is maintained by the sealing board 64 of the
connector unit 60.
[0071] According to the HDD associated with the third embodiment
configured as described above, in the fixation structure of the
sealing board 64, the annular rib (projection) 74 is provided on
the installation surface 72 around the through-hole 58, and the
sealing board 64 is arranged in a state where the first principal
surface 64a of the sealing board 64 is made in contact with the end
face 74a of the rib 74, whereby it is possible to position the
sealing board 64 in terms of the height position, i.e., the
position in the thickness direction of the sealing board 64 with
respect to the installation surface 72. Thereby, it is possible to
maintain the gap between the first principal surface 64a of the
sealing board 64 and the installation surface 72 constant, and
manage the thickness of the sealant 82 to be filled into this gap
constant. Further, it is possible by the rib 74 to prevent the
sealant 82 from flowing into the inside of the through-hole 58, and
retain the sealant 82 in the desired space. Furthermore, according
to this embodiment, the stepped portions 78 are provided on the
installation surface 72 on the outside of the rib 74. By virtue of
these stepped portions 78, it is possible to suppress the flow of
the sealant 82, and retain the sealant 82 in the desired space.
Therefore, according to this embodiment, it becomes possible to
reduce unnecessary spread and wetting of the sealant, and securely
seal the desired space with a minimum amount of the sealant.
Further, according to this embodiment, by omitting the connectors
provided on the sealing board 64, it becomes possible to reduce the
number of components, and simplify the configuration.
[0072] From the above description, according to the third
embodiment, it is possible to obtain a disk device which is
improved in the airtightness of the housing, and can easily be
connected to the connector or the control circuit board outside the
housing.
[0073] In the third embodiment described above, although the
configuration is contrived in such a manner that the projection in
the installation part is provided on the installation surface of
the base 12, the configuration is not limited to this, and the
projection may be provided on the sealing board 64 side. According
to a second modification example shown in FIG. 13, a sealing board
64 includes a plurality of conductive pads 86a provided on a first
principal surface 64a, and a substantially rectangular projection
90 provided around these conductive pads 86a. The projection 90 is
formed of, for example, a resist layer provided on the first
principal surface 64a. The projection 90 has a constant height (for
example, 0.1 mm) over the entire top surface thereof and,
furthermore, the top surface (contact surface) of the projection 90
is formed flat.
[0074] Further, the sealing board 64 is not limited to a
multi-layered circuit board, and may be formed of other materials,
for example, glass or ceramic. When glass or ceramic is used as the
material, the conductive paths of the sealing board 64 may be
constituted of a plurality of conductive pins embedded in the
sealing board 64.
[0075] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
inventions.
[0076] For example, in the first, second, and third embodiments,
the projection is not limited to a continuous annular rib, and
projection divisions formed by dividing a projection into a
plurality of divisions may be used. The shape of the projection is
not limited to the rectangular shape, and is variously selectable.
The shape of the sealing board of the connector unit, and the
formation material for the sealing board are not limited to those
in the aforementioned embodiments, and can be variously varied. The
number of the positioning pins or the positioning holes is not
limited to two, three or more positioning pins or positioning holes
may be provided as the need arises. As in a third modification
example shown in FIG. 14, a notch 92 may be provided in a part of
the rib 74 serving as a projection. When a sealant, for example,
solder is to be filled into the space between the installation
surface 72 and the sealing board, by exhausting air from the inside
of the rib 74 through the notch 92, it is possible to prevent air
bubbles from occurring in the sealant.
[0077] Utilization of the connector unit 60 is not limited to the
connection between the board unit inside the housing and the
control circuit board outside the housing, and may be applied to a
connection between other components. The materials, shapes, sizes,
and the like of the elements constituting the disk drive may be
changed as the need arises. In the disk drive, the number of
magnetic disks, and the number of magnetic heads can be increased
or decreased as the need arises, and the size of the magnetic disk
is variously selectable.
* * * * *