Disk device

Abstract

Embodiments of the present invention relate to a disc device, which includes a first conversion device, a second conversion device, an optical waveguide, a first component, and a second component. The first conversion device emits light corresponding to an electrical signal. The second conversion device generates an electrical signal corresponding to the incident light. The optical waveguide has a first end joined to the first conversion device and a second end joined to the second conversion device, and transmits the light emitted by the first conversion device to the second conversion device. The first component is electrically connected to the first conversion device. The second component is electrically connected to the second conversion device and communicates with the first component through the first conversion device, the optical waveguide, and the second conversion device.

Description

[0001] This application claims the priority of Japanese Patent Application No. 2021-44837 filed on March 18, 2021, and the entire content of the Japanese patent application is incorporated herein by reference. Technical Field

[0002] This embodiment generally relates to a disk device. Background Art

[0003] In a disk device such as a hard disk drive, various electrical signals are transmitted through a wiring pattern on a substrate and wiring including terminals of a connector. The electrical signals include, for example, a write signal corresponding to information written by a magnetic head to a recording medium and a read signal corresponding to information read by the magnetic head from the recording medium.

[0004] As the storage capacity of the disk device increases, there is a tendency for the number of wirings in the disk device to increase. For example, since the number of storage media increases, the number of magnetic heads for reading and writing information with respect to the storage media increases, and the number of wirings connected to the magnetic heads also increases. Summary of the Invention

[0005] An embodiment of the present invention provides a disk device capable of reducing the number of wirings.

[0006] According to one embodiment, a disk device includes a first conversion device, a second conversion device, an optical waveguide, a first component, and a second component. The first conversion device emits light corresponding to an electrical signal. The second conversion device generates an electrical signal corresponding to the incident light. The optical waveguide has a first end joined to the first conversion device and a second end joined to the second conversion device, and transmits the light emitted from the first conversion device toward the second conversion device. The first component is electrically connected to the first conversion device. The second component is electrically connected to the second conversion device and communicates with the first component through the first conversion device, the optical waveguide, and the second conversion device. Brief Description of the Drawings

[0007] Figure 1 is an exemplary perspective view showing a hard disk drive (HDD) according to the first embodiment.

[0008] Figure 2 is an exemplary perspective view showing an exploded view of the HDD according to the first embodiment.

[0009] Figure 3 is an exploded view of the HDD according to the first embodiment and shows an exemplary perspective view from a Figure 2 different direction.

[0010] Figure 4 is an exemplary block diagram showing the configuration of the HDD according to the first embodiment.

[0011] Figure 5 is schematically shown along Figure 3 the F5-F5 line of a part of the HDD of the first embodiment.

[0012] Figure 6 is a schematic plan view schematically showing the bottom wall and the relay FPC of the first embodiment.

[0013] Figure 7 is a schematic plan view schematically showing the FPC of the second embodiment.

[0014] Figure 8 is a schematic sectional view schematically showing a part of the HDD of the third embodiment.

[0015] Figure 9 is a schematic sectional view schematically showing a part of the HDD of the fourth embodiment. Detailed Embodiments

[0016] (First Embodiment)

[0017] Hereinafter, with reference to Figures 1 to 6 the first embodiment will be described. In addition, in this specification, the components of the embodiment and the description of the component may be described by multiple expressions. The component and its description are an example and are not limited by the expressions in this specification. Even if the name is different from the component in this specification, the component can be determined. In addition, the component can also be described by an expression different from the expression in this specification.

[0018] Figure 1 is an exemplary perspective view showing the hard disk drive (HDD) 10 of the first embodiment. The HDD 10 is mounted on, for example, an electronic device 1 and forms a part of the electronic device 1. In other words, the electronic device 1 has the HDD 10.

[0019] The HDD 10 is an example of a disk device and can also be referred to as a storage device or a disk device. The electronic device 1 is, for example, various computers such as a personal computer, a supercomputer, a server, a television receiver, or a game console, or a device such as an external hard drive.

[0020] Figure 2 is an exemplary perspective view showing the HDD 10 of the first embodiment in an exploded manner. As Figure 2As shown, the HDD 10 has a housing 11, a plurality of disks 12, a spindle motor 13, a clamping spring 14, a plurality of heads 15, an actuator assembly 16, a voice coil motor (VCM) 17, a ramp loading mechanism 18, and a flexible printed circuit board (FPC) 19. The disk 12 is an example of a recording medium. The actuator assembly 16 is an example of an actuator. The FPC 19 is an example of a first flexible printed wiring board.

[0021] The housing 11 has a base 21, an inner cover 22, and an outer cover 23. The base 21 is a bottomed container having a bottom wall 25 and a side wall 26. The bottom wall 25 is an example of a first wall. The bottom wall 25 is formed in a substantially rectangular (quadrilateral) plate shape. The side wall 26 projects from the outer edge of the bottom wall 25. The bottom wall 25 and the side wall 26 are integrally formed, for example, of a metal material such as aluminum alloy.

[0022] The inner cover 22 and the outer cover 23 are made of, for example, a metal material such as aluminum alloy. The inner cover 22 is attached to the end of the side wall 26 by screws, for example. The outer cover 23 covers the inner cover 22 and is hermetically fixed to the end of the side wall 26 by welding, for example.

[0023] A storage space S is provided inside the housing 11. The storage space S is formed (defined, delimited) by the base 21 and the inner cover 22. The housing 11 of the present embodiment hermetically seals the storage space S to prevent or reduce the movement of gas between the storage space S and the outside of the housing 11.

[0024] Various components including the disk 12, the spindle motor 13, the clamping spring 14, the head 15, the actuator assembly 16, the voice coil motor 17, the ramp loading mechanism 18, and the FPC 19 are located in the storage space S inside the housing 11. The storage space S and the various components stored in the storage space S are covered by the bottom wall 25 and the side wall 26 of the base 21 and the inner cover 22.

[0025] An air vent 22a is provided in the inner cover 22. Further, an air vent 23a is provided in the outer cover 23. After installing components inside the base 21 and attaching the inner cover 22 and the outer cover 23 to the base 21, the air in the storage space S is discharged from the air vents 22a, 23a. Further, a gas different from air is filled in the storage space S.

[0026] The gas filled in the storage space S is, for example, a low-density gas having a density lower than that of air, an inert gas with low reactivity, or the like. For example, helium is filled in the storage space S. Alternatively, other fluids may be filled in the storage space S. In addition, the storage space S may be maintained in a vacuum, a low pressure close to vacuum, or a negative pressure lower than atmospheric pressure.

[0027] The vent hole 23a of the outer cover 23 is blocked by a seal 28. The seal 28 is made of, for example, metal or synthetic resin. The seal 28 hermetically seals the vent hole 23a to prevent the gas filled in the storage space S from leaking out through the vent hole 23a.

[0028] The magnetic disk 12 is, for example, a disk having a magnetic recording layer provided on at least one of the upper surface and the lower surface. The diameter of the magnetic disk 12 is, for example, 3.5 inches, but is not limited to this example.

[0029] The spindle motor 13 supports and rotates a plurality of magnetic disks 12 that are overlapped with a space therebetween. The clamping spring 14 holds the plurality of magnetic disks 12 on the hub of the spindle motor 13.

[0030] The magnetic head 15 records and reproduces information on the recording layer of the magnetic disk 12. In other words, the magnetic head 15 writes information to the magnetic disk 12. The magnetic head 15 is supported by an actuator assembly 16.

[0031] The actuator assembly 16 is rotatably supported by a support shaft 31, and the support shaft 31 is disposed at a position separated from the magnetic disk 12. The VCM 17 rotates the actuator assembly 16 and positions it at a desired position. When the actuator assembly 16 is rotated by the VCM 17 and the magnetic head 15 moves to the outermost circumference of the magnetic disk 12, the ramp loading mechanism 18 holds the magnetic head 15 at an unloading position separated from the magnetic disk 12.

[0032] The actuator assembly 16 includes an actuator block 35, a plurality of arms 36, and a plurality of head suspension assemblies 37. The head suspension assembly 37 can also be referred to as a head gimbal assembly (HGA).

[0033] The actuator block 35 is rotatably supported by the support shaft 31 via a bearing, for example. The plurality of arms 36 project from the actuator block 35 in a direction substantially orthogonal to the support shaft 31. Alternatively, the actuator assembly 16 may be divided, and a plurality of arms 36 may project from a plurality of actuator blocks 35, respectively.

[0034] The plurality of arms 36 are arranged at intervals in the direction in which the support shaft 31 extends. Each arm 36 is formed in a plate shape capable of entering the gap between adjacent magnetic disks 12. The plurality of arms 36 extend substantially parallel to each other.

[0035] The actuator block 35 and the plurality of arms 36 are integrally formed of aluminum, for example. In addition, the materials of the actuator block 35 and the arms 36 are not limited to this example.

[0036] A voice coil of the VCM 17 is provided on a projection projecting from the actuator block 35. The VCM 17 has a pair of magnetic yokes, a voice coil disposed between the magnetic yokes, and a magnetic head provided on the magnetic yokes.

[0037] The head suspension assembly 37 is mounted on the front end portion of the corresponding arm 36 and projects from the arm 36. Thus, a plurality of head suspension assemblies 37 are arranged at intervals in the direction in which the support shaft 31 extends.

[0038] Each of the plurality of head suspension assemblies 37 includes a substrate 41, a load beam 42, and a flexure 43. Further, a head 15 is mounted on the head suspension assembly 37.

[0039] The substrate 41 and the load beam 42 are made of, for example, stainless steel. In addition, the materials of the substrate 41 and the load beam 42 are not limited to this example. The substrate 41 is formed in a plate shape and is mounted on the front end portion of the arm 36. The load beam 42 is formed in a plate shape thinner than the substrate 41. The load beam 42 is mounted on the front end portion of the substrate 41 and projects from the substrate 41.

[0040] The flexure 43 is formed in an elongated strip shape. In addition, the shape of the flexure 43 is not limited to this example. The flexure 43 is a laminated plate having a metal plate (liner layer) such as stainless steel, an insulating layer formed on the metal plate, a conductive layer formed on the insulating layer and constituting a plurality of wirings (wiring patterns), and a protective layer (insulating layer) covering the conductive layer.

[0041] At one end of the flexure 43, a gimbal portion (elastic support portion) that is located above the load beam 42 and can be displaced is provided. The head 15 is mounted on the gimbal portion. The other end of the flexure 43 is connected to the FPC 19. Thus, the FPC 19 is electrically connected to the head 15 via the wiring of the flexure 43.

[0042] The actuator assembly 16 is rotated by the VCM 17, and thus the head 15 mounted on the gimbal portion of the actuator assembly 16 also moves around the support shaft 31. That is, the actuator assembly 16 and the VCM 17 move the head 15.

[0043] Figure 3 is an exemplary perspective view showing the HDD 10 of the first embodiment disassembled and viewed from a direction different from Figure 2 As shown, the HDD 10 further includes a printed circuit board (PCB) 50. The PCB 50 is disposed outside the bottom wall 25 of the base 21. Figure 3 As shown, the HDD 10 further includes a printed circuit board (PCB) 50. The PCB 50 is disposed outside the bottom wall 25 of the base 21.

[0044] The PCB 50 includes a printed wiring board (PWB) 51 and a plurality of components mounted on the PWB 51. The PWB 51 is, for example, a rigid substrate such as a glass epoxy substrate, and is a multi-layer substrate, a composite substrate, or the like. The PWB 51 is mounted outside the bottom wall 25. In other words, the PWB 51 is mounted on the housing 11 outside the housing 11. The PWB 51 is mounted on the bottom wall 25, for example, by screw threading or by snap fitting based on a hook.

[0045] Figure 4 is an exemplary block diagram showing the configuration of the HDD 10 according to the first embodiment. As Figure 4 shown, the PCB 50 also has an interface (I / F) connector 52, a controller 53, a servo controller 54, and a relay connector 55. The controller 53 is an example of the first component or the second component.

[0046] The I / F connector 52, the controller 53, the servo controller 54, and the relay connector 55 are mounted on the PWB 51. In addition, various memories such as a RAM, a ROM, and a buffer memory, coils, capacitors, and other electronic components are also mounted on the PWB 51.

[0047] The I / F connector 52 is a connector compliant with an interface standard such as Serial ATA, and is connected to the I / F connector 1a of the electronic device 1. Thereby, the PWB 51 is electrically connected to the processor 1b of the electronic device 1. The processor 1b is, for example, a CPU (Central Processing Unit), and controls the entire electronic device 1.

[0048] The HDD 10 receives power supply from the electronic device 1 through the I / F connector 52, and receives access commands (control signals) such as write commands and read commands, and various data. In addition, the HDD 10 sends various data to the electronic device 1 through the I / F connector 52. Thus, the HDD 10 performs wired communication with the electronic device 1 through the I / F connector 52. In addition, the HDD 10 may be able to perform wireless communication with the electronic device 1.

[0049] The controller 53 includes, for example, a read / write channel (RWC), a hard disk controller (HDC), and a processor. The controller 53 may be a single component, or may be a collective term for the RWC, the HDC, and the processor that are independent of each other. The controller 53 controls the entire HDD 10.

[0050] The servo controller 54 drives the spindle motor 13 and the VCM 17. The relay connector 55 is used, for example, for communication and power supply with various components disposed in the accommodation space S.

[0051] As Figure 3 shown, the HDD 10 also has a relay FPC 59. The spindle motor 13 is electrically connected to the servo controller 54 of the PCB 50 through the relay FPC 59. The spindle motor 13 inputs a drive signal from the servo controller 54 through the relay FPC 59, and receives power supply from the PCB 50.

[0052] The relay FPC 59 passes through a hole that is located near the spindle motor 13 and penetrates the bottom wall 25 of the base 21, and extends across the accommodation space S and the outside of the housing 11. This hole is sealed with a synthetic resin, for example.

[0053] Figure 2 The FPC 19 shown, for example, has conductor layers, insulating layers, and adhesive layers stacked on one another and can be elastically deformed. The conductor layer is made of a conductive metal such as copper, for example. The insulating layer is made of an insulating synthetic resin such as polyimide, for example.

[0054] A preamplifier 61 and a relay connector 62 are mounted on the FPC 19. Accordingly, the preamplifier 61 and the relay connector 62 are located in the accommodation space S inside the housing 11. The preamplifier 61 is an example of the first component or the second component. In addition, the preamplifier 61 is also an example of an amplifier.

[0055] The preamplifier 61 is electrically connected to the magnetic head 15 through the flexible member 43. Alternatively, the preamplifier 61 may be mounted on the flexible member 43. The preamplifier 61, for example, amplifies and outputs an input electrical signal.

[0056] The relay connector 62 receives power supply via the relay connector 55 of the PWB 51. In the present embodiment, the magnetic head 15 and the preamplifier 61 operate with the power supplied via the relay connector 62.

[0057] The HDD 10 further includes a relay FPC 70 and two relay connectors 71, 72. The relay FPC 70 is an example of the first flexible printed circuit board or the second flexible printed circuit board. The relay connector 71 is an example of the first connector. The relay connector 72 is an example of the second connector.

[0058] Similar to the FPC 19, the relay FPC 70, for example, has conductor layers, insulating layers, and adhesive layers stacked on one another and can be elastically deformed. Alternatively, the configuration of the relay FPC 70 may be different from the configuration of the FPC 19.

[0059] The relay FPC 70 is mounted on the bottom wall 25 of the housing 11. The relay connectors 71, 72 are provided on the relay FPC 70. The relay connector 71 is located outside the housing 11. The relay connector 71 is connected to the relay connector 55 of the PCB 50. The relay connector 72 is located in the accommodation space S inside the housing 11. The relay connector 72 is connected to the relay connector 62 of the FPC 19.

[0060] The processor 1b of the electronic device 1 outside the housing 11, the controller 53 of the PCB 50, the magnetic head 15 and the preamplifier 61 inside the housing 11 communicate (transmit and receive data) through the relay connectors 55, 62, 71, 72 and the relay FPC 70. In addition, the communication in this embodiment means the transmission and reception of information between independent elements. Therefore, the processor 1b, the controller 53, the magnetic head 15 and the preamplifier 61 do not need to perform various controls such as signal conversion for communication. The processor 1b, the controller 53, the magnetic head 15 and the preamplifier 61 only need to be in a relationship where when one outputs a signal, the other is input with a signal corresponding to that signal.

[0061] Hereinafter, the structure of the HDD 10 of this embodiment will be described in detail. Figure 5 is an exemplary cross-sectional view schematically showing a part of the HDD 10 of the first embodiment along the F5-F5 line. As Figure 3 shown, the bottom wall 25 of the base 21 has an inner surface 25a and an outer surface 25b. Figure 5 As shown, the inner surface 25a faces the inside of the housing 11. The inner surface 25a forms (defines, divides) a part of the storage space S inside the housing 11. In other words, the inner surface 25a faces the storage space S. The inner surface 25a faces various components such as the FPC 19 disposed in the storage space S.

[0062] The outer surface 25b is located on the opposite side of the inner surface 25a and faces the outside of the housing 11. The outer surface 25b faces the PCB 50 at an interval. In addition, the outer surface 25b and the PCB 50 may be in contact with each other.

[0063]

[0064] A slit 25c is provided in the bottom wall 25. The slit 25c is an example of the first through hole. The slit 25c penetrates the bottom wall 25 and opens on the inner surface 25a and the outer surface 25b. In other words, the slit 25c communicates the storage space S with the outside of the housing 11.

[0065] Figure 6 is an exemplary plan view schematically showing the bottom wall 25 and the relay FPC 70 of the first embodiment. As Figure 6 shown, the slit 25c is, for example, a substantially rectangular (quadrilateral) hole. In addition, the shape of the slit 25c is not limited to this example.

[0066] As Figure 2 shown, the FPC 19 has a first part 19a, a second part 19b and a third part 19c. The first part 19a is provided at one end of the FPC 19. The second part 19b is provided at the other end of the FPC 19.

[0067] The first portion 19a is mounted on the actuator block 35 of the actuator assembly 16, for example, by screws. The first portion 19a is electrically connected to the flexible member 43.

[0068] The second portion 19b is mounted on the bottom wall 25 of the housing 11, for example, by screws. As Figure 5 shown, the second portion 19b of the FPC 19 is disposed substantially along the inner surface 25a of the bottom wall 25.

[0069] As Figure 2 shown, the third portion 19c is provided between the first portion 19a and the second portion 19b. The third portion 19c is formed to be substantially strip-shaped and is flexible. For example, when the actuator assembly 16 rotates, the third portion 19c flexes to absorb the relative movement between the first portion 19a and the second portion 19b caused by the rotation.

[0070] As Figure 5 shown, the FPC 19 also has a surface 19d. The surface 19d is one face of the FPC 19. Accordingly, the first portion 19a, the second portion 19b, and the third portion 19c of the FPC 19 all partially have the surface 19d.

[0071] In the second portion 19b, the surface 19d faces the inner surface 25a of the bottom wall 25. Additionally, the surface 19d may also be in partial contact with the inner surface 25a of the bottom wall 25. The relay connector 62 projects from the surface 19d in the second portion 19b.

[0072] The PWB 51 has an inner surface 51a. The inner surface 51a faces the outer surface 25b of the bottom wall 25 with a gap therebetween. The inner surface 51a covers the slit 25c of the bottom wall 25. Further, the inner surface 51a faces the surface 19d of the FPC 19 through the slit 25c. The relay connector 55 projects from the inner surface 51a.

[0073] The relay FPC 70 has an external portion 75, an internal portion 76, and an intermediate portion 77. The external portion 75, the internal portion 76, and the intermediate portion 77 are part of the relay FPC 70 and are arranged along the extending direction of the relay FPC 70.

[0074] The external portion 75 is provided, for example, at one end of the relay FPC 70. The external portion 75 is located outside the housing 11. The external portion 75 extends, for example, along the outer surface 25b of the bottom wall 25. Additionally, the external portion 75 is not limited to this example.

[0075] The internal portion 76 is provided, for example, at the other end of the relay FPC 70. The internal portion 76 is located in the accommodation space S inside the housing 11. The internal portion 76 extends, for example, along the inner surface 25a of the bottom wall 25. Additionally, the internal portion 76 is not limited to this example.

[0076] The intermediate portion 77 is disposed between the external portion 75 and the internal portion 76. The intermediate portion 77 penetrates the slit 25c. The external portion 75 extends from the end of the intermediate portion 77 located outside the housing 11. The internal portion 76 extends from the end of the intermediate portion 77 located inside the housing 11. Thus, the relay FPC 70 is disposed across the inside and outside of the housing 11.

[0077] The external portion 75 has an inner surface 75a and an outer surface 75b. The inner surface 75a faces the outer surface 25b of the housing 11. The outer surface 75b is located on the opposite side of the inner surface 75a. The outer surface 75b faces the inner surface 51a of the PWB 51 with a space therebetween. The relay connector 71 projects from the outer surface 75b of the external portion 75.

[0078] The internal portion 76 has an inner surface 76a and an outer surface 76b. The inner surface 76a faces the inner surface 25a of the housing 11. The outer surface 76b is located on the opposite side of the inner surface 76a. The outer surface 76b faces the surface 19d of the FPC 19 with a space therebetween. The relay connector 72 projects from the outer surface 76b of the internal portion 76.

[0079] The relay FPC 70 is fixed to the bottom wall 25 by an adhesive 78. The adhesive 78 fixes the inner surface 75a of the external portion 75 to the outer surface 25b of the bottom wall 25 and fixes the inner surface 76a of the internal portion 76 to the inner surface 25a of the bottom wall 25. Further, the adhesive 78 is filled between the intermediate portion 77 and the inner surface of the slit 25c. The adhesive 78 contains, for example, a metal filler and can inhibit gas from passing through the adhesive 78. Thus, the adhesive 78 hermetically seals the slit 25c.

[0080] The HDD 10 further has a communication unit 80. The communication unit 80 communicates using light between two components. In the present embodiment, the communication unit 80 communicates between the controller 53 outside the housing 11 and the preamplifier 61 inside the housing 11. The communication unit 80 has two conversion devices 81, 82 and an optical waveguide 83. The communication unit 80 may have a plurality of optical waveguides 83. The conversion devices 81, 82 are respectively an example of a first conversion device or a second conversion device.

[0081] The conversion devices 81, 82 each have, for example, a light source, a light receiving element, and a conversion IC. In the conversion devices 81, 82 of the present embodiment, the light source, the light receiving element, and the conversion IC are integrally formed. Additionally, the light source, the light receiving element, and the conversion IC of the conversion devices 81, 82 may be different components from each other.

[0082] The light sources of the conversion devices 81 and 82 are, for example, laser diodes (LDs) or light-emitting diodes (LEDs). The light-receiving elements are, for example, photodiodes or phototransistors. The conversion IC causes the light source to emit light corresponding to the input electrical signal, and outputs an electrical signal corresponding to the light incident on the light-receiving element. The conversion IC can also perform multiplexing. That is, the conversion devices 81 and 82 respectively emit light corresponding to the electrical signal, and generate an electrical signal corresponding to the incident light. Alternatively, one of the conversion devices 81 and 82 may have a light source for emitting light, and the other may have a light-receiving element for generating an electrical signal.

[0083] The conversion device 81 is mounted on the PWB 51. The conversion device 81 is electrically connected to the controller 53 through the wiring of the PWB 51. Additionally, other components may be provided on the wiring between the conversion device 81 and the controller 53.

[0084] The conversion device 82 is mounted on the FPC 19. The conversion device 82 is electrically connected to the preamplifier 61 through the wiring of the FPC 19. Additionally, other components may be provided on the wiring between the conversion device 82 and the preamplifier 61.

[0085] The optical waveguide 83 has, for example, a transparent core layer and a cladding layer surrounding the core layer. The refractive index of the core layer is different from that of the cladding layer. Therefore, the optical waveguide 83 causes the light incident on the core layer to be totally reflected at the interface between the core layer and the cladding layer and transmitted. Additionally, the optical waveguide 83 is not limited to this example.

[0086] The optical waveguide 83 is provided, for example, inside substrates such as the FPC 19 and the PWB 51, and is formed in a sheet shape or a rod shape. Additionally, the optical waveguide 83 is not limited to this example. Furthermore, the rod-shaped optical waveguide 83 is also referred to as an optical fiber.

[0087] The optical waveguide 83 has two ends 83a and 83b. The ends 83a and 83b are respectively an example of the first end or the second end. One end 83a is joined to the conversion device 81. The other end 83b is joined to the conversion device 82.

[0088] In this embodiment, "joining" means that two components are mutually mounted and fixed. For example, the ends 83a and 83b are directly mounted on the conversion devices 81 and 82, or indirectly mounted on the conversion devices 81 and 82 via other components. The ends 83a and 83b are mutually fixed to the conversion devices 81 and 82 through this mounting, and relative movement is suppressed.

[0089] The optical waveguide 83 emits, for example, light incident from one of the ends 83a and 83b from the other of the ends 83a and 83b. Therefore, the optical waveguide 83 transmits the light emitted from one of the conversion devices 81 and 82 toward the other.

[0090] Between the conversion device 81 and the conversion device 82, a single optical waveguide 83 can be connected, or a plurality of optical waveguides included in the optical waveguide 83 can be connected. In the case where the optical waveguide 83 includes a plurality of optical waveguides, the plurality of optical waveguides are joined to each other by a connector, for example. Thereby, the optical waveguide 83 can transmit light between the ends 83a and 83b of the optical waveguide 83 as a whole.

[0091] In the present embodiment, the optical waveguide 83 has a first optical waveguide 91, a second optical waveguide 92, a third optical waveguide 93, a fourth optical waveguide 94, a fifth optical waveguide 95, a sixth optical waveguide 96, and a seventh optical waveguide 97. In addition, the optical waveguide 83 is not limited to this example.

[0092] The first optical waveguide 91 is provided on the PWB 51, for example. In addition, the first optical waveguide 91 can also be a component different from the PWB 51. The first optical waveguide 91 has the end 83a of the optical waveguide 83. Therefore, the first optical waveguide 91 is joined to the conversion device 81. Further, the first optical waveguide 91 is joined to the relay connector 55 of the PCB 50.

[0093] For example, the first optical waveguide 91 is provided on one of the plurality of layers of the PWB 51. The first optical waveguide 91 is covered with an insulating layer forming the inner surface 51a of the PWB 51 except for both ends, for example. The end 83a included in the first optical waveguide 91 is exposed through an opening provided in the insulating layer and faces the light source and the light receiving element of the conversion device 81. The conversion device 81 is fixed to the PWB 51 by soldering, for example. Therefore, the end 83a is indirectly fixed to the conversion device 81 via the PWB 51 and solder. The end 83a is not limited to this example and can also be directly joined to the conversion device 81, for example.

[0094] The second optical waveguide 92 is provided on the FPC 19, for example. In addition, the second optical waveguide 92 can also be a component different from the FPC 19. The second optical waveguide 92 has flexibility. Therefore, the second optical waveguide 92 can bend following the bending of the FPC 19.

[0095] The second optical waveguide 92 has the end 83b of the optical waveguide 83. Therefore, the second optical waveguide 92 is joined to the conversion device 82. Further, the second optical waveguide 92 is joined to the relay connector 62 mounted on the FPC 19.

[0096] For example, the second optical waveguide 92 is provided in one of the multiple layers of the FPC 19. The second optical waveguide 92 is covered by an insulating layer forming the surface 19d of the FPC 19, except for its two end portions. The end portion 83b included in the second optical waveguide 92 is exposed through an opening provided in the insulating layer and faces the light source and the light-receiving element of the conversion device 82. The conversion device 82 is fixed to the FPC 19 by soldering, for example. Therefore, the end portion 83b is indirectly fixed to the conversion device 82 via the FPC 19 and solder. The end portion 83b is not limited to this example and may be directly joined to the conversion device 82, for example.

[0097] The third optical waveguide 93 is provided in the relay FPC 70. The third optical waveguide 93 is provided in one of the multiple layers of the relay FPC 70, for example. The third optical waveguide 93 has an outer terminal 93a, an inner terminal 93b, and an extension portion 93c.

[0098] The outer terminal 93a is provided on the outer surface 75b of the outer portion 75 of the relay FPC 70. The inner terminal 93b is provided on the outer surface 76b of the inner portion 76. For example, the outer terminal 93a and the inner terminal 93b are exposed through openings in the insulating layer of the relay FPC 70 that forms the outer surfaces 75b and 76b. The extension portion 93c extends through the outer portion 75, the inner portion 76, and the intermediate portion 77 to connect the outer terminal 93a and the inner terminal 93b.

[0099] For example, the first to third optical waveguides 91 to 93 are provided by forming a core layer and a cladding in desired portions of the layers of the substrate using etching. Thus, the first to third optical waveguides 91 to 93 can be formed by the same processes as the wiring patterns in general PWBs and FPCs. Additionally, the first to third optical waveguides 91 to 93 may be formed by other methods.

[0100] The fourth optical waveguide 94 is provided in the relay connector 55. The fourth optical waveguide 94 is mounted on a plug-shaped or socket-shaped relay connector 55 made of synthetic resin or other materials, for example.

[0101] One end portion of the fourth optical waveguide 94 is joined to the first optical waveguide 91. For example, the relay connector 55 is fixed to the inner surface 51a of the PWB 51 by screws or an adhesive. Therefore, one end portion of the fourth optical waveguide 94 is indirectly fixed to the first optical waveguide 91 via the relay connector 55, screws or an adhesive, and the PWB 51. The fourth optical waveguide 94 is not limited to this example and may be directly joined to the first optical waveguide 91, for example.

[0102] For example, the light emitted from the end of the fourth optical waveguide 94 is reflected at the end of the first optical waveguide 91 by bending approximately 90° and is transmitted by the first optical waveguide 91. In addition, the light transmitted by the first optical waveguide 91 is reflected at the end of the first optical waveguide 91 by bending approximately 90° and is incident on the end of the fourth optical waveguide 94.

[0103] The fifth optical waveguide 95 is provided in the relay connector 62. The fifth optical waveguide 95 is mounted, for example, on a plug-shaped or socket-shaped relay connector 62 made of synthetic resin or other materials.

[0104] One end of the fifth optical waveguide 95 is joined to the second optical waveguide 92. For example, the relay connector 62 is fixed to the surface 19d of the FPC 19 by screws or an adhesive. Therefore, one end of the fifth optical waveguide 95 is indirectly fixed to the second optical waveguide 92 via the relay connector 62, screws or an adhesive, and the FPC 19. The fifth optical waveguide 95 is not limited to this example, and for example, it may also be directly joined to the second optical waveguide 92.

[0105] For example, the light emitted from the end of the fifth optical waveguide 95 is reflected at the end of the second optical waveguide 92 by bending approximately 90° and is transmitted by the second optical waveguide 92. In addition, the light transmitted by the second optical waveguide 92 is reflected at the end of the second optical waveguide 92 by bending approximately 90° and is incident on the end of the fifth optical waveguide 95.

[0106] The sixth optical waveguide 96 is provided in the relay connector 71. The sixth optical waveguide 96 is mounted, for example, on a plug-shaped or socket-shaped relay connector 71 made of synthetic resin or other materials.

[0107] One end of the sixth optical waveguide 96 is joined to the outer terminal 93a of the third optical waveguide 93. For example, the relay connector 71 is fixed to the outer surface 75b of the external portion 75 by screws or an adhesive. Therefore, one end of the sixth optical waveguide 96 is indirectly fixed to the third optical waveguide 93 via the relay connector 71, screws or an adhesive, and the relay FPC 70. The sixth optical waveguide 96 is not limited to this example, and for example, it may also be directly joined to the third optical waveguide 93.

[0108] For example, the light emitted from the end of the sixth optical waveguide 96 is reflected at the outer terminal 93a by bending approximately 90° and is transmitted by the third optical waveguide 93. In addition, the light transmitted by the third optical waveguide 93 is reflected at the outer terminal 93a by bending approximately 90° and is incident on the end of the sixth optical waveguide 96.

[0109] When the relay connectors 55 and 71 are connected to each other, the fourth optical waveguide 94 and the sixth optical waveguide 96 are joined to each other via the relay connectors 55 and 71. Thus, the fourth optical waveguide 94 and the sixth optical waveguide 96 can transmit light to each other.

[0110] The seventh optical waveguide 97 is provided in the relay connector 72. The seventh optical waveguide 97 is mounted, for example, on a plug-shaped or socket-shaped relay connector 72 made of synthetic resin or other materials.

[0111] One end of the seventh optical waveguide 97 is joined to the inner terminal 93b of the third optical waveguide 93. For example, the relay connector 72 is fixed to the outer surface 76b of the inner part 76 by screws or an adhesive. Therefore, one end of the seventh optical waveguide 97 is indirectly fixed to the third optical waveguide 93 via the relay connector 72, screws or an adhesive, and the relay FPC 70. The seventh optical waveguide 97 is not limited to this example and may be directly joined to the third optical waveguide 93.

[0112] For example, the light emitted from the end of the seventh optical waveguide 97 is reflected at the inner terminal 93b by about 90° and transmitted by the third optical waveguide 93. In addition, the light transmitted by the third optical waveguide 93 is reflected at the inner terminal 93b by about 90° and incident on the end of the seventh optical waveguide 97.

[0113] When the relay connectors 62 and 72 are connected to each other, the fifth optical waveguide 95 and the seventh optical waveguide 97 are joined to each other via the relay connectors 62 and 72. Thereby, the fifth optical waveguide 95 and the seventh optical waveguide 97 can transmit light to each other.

[0114] In the communication unit 80, the conversion devices 81 and 82 convert an electrical signal into an optical signal, transmit the optical signal through the optical waveguide 83, and convert the optical signal into an electrical signal. Thereby, the communication unit 80 can perform wired communication of the optical signal passing through the optical waveguide 83.

[0115] The conversion devices 81 and 82 perform signal conversion and generation, for example, based on a common communication method. Furthermore, the light sources of the conversion devices 81 and 82 emit light at frequencies that can be detected by the light receiving elements of each other. In addition, the conversion devices 81 and 82 are not limited to visible light and may emit infrared light or ultraviolet light.

[0116] Via the above communication unit 80, the controller 53 and the preamplifier 61 communicate with each other. In the present embodiment, the communication unit 80 transmits an electrical signal (read signal) corresponding to the data read from the disk 12 and an electrical signal (write signal) corresponding to the data to be written between the controller 53 and the preamplifier 61.

[0117] For example, the preamplifier 61 outputs an amplified electrical signal (read signal) corresponding to the data read from the disk 12 by the magnetic head 15 during data reading. The communication unit 80 supplies the read signal amplified by the preamplifier 61 to the RWC of the controller 53.

[0118] Furthermore, the preamplifier 61 amplifies an electrical signal (write signal) corresponding to the data to be written supplied from the RWC of the controller 53 via the communication unit 80. The preamplifier 61 supplies this signal to the magnetic head 15.

[0119] On the other hand, the HDC of the controller 53 controls, for example, data transmission / reception between the electronic device 1 via the I / F connector 52, controls the buffer memory, and performs error correction processing on the read data.

[0120] The RWC of the controller 53 modulates, for example, the data to be written supplied from the HDC and supplies it to the preamplifier 61 via the communication unit 80. Furthermore, the RWC demodulates the signal read from the magnetic disk 12 and supplied from the preamplifier 61 via the communication unit 80, and outputs it as digital data to the HDC.

[0121] The processor of the controller 53 is, for example, a CPU. The processor performs overall control of the HDD 10 based on the firmware stored in advance in the ROM and the magnetic disk 12. For example, the processor loads the firmware of the ROM and the magnetic disk 12 into the RAM, and controls the magnetic head 15, the servo controller 54, the preamplifier 61, the conversion devices 81, 82, the RWC, the HDC, and other components according to the loaded firmware.

[0122] The HDD 10 also has a power supply unit 100. The power supply unit 100 is an example of a second conductive part. The power supply unit 100 electrically connects between a plurality of components. In the present embodiment, the power supply unit 100 electrically connects the PCB 50 outside the housing 11 to the magnetic head 15 and the preamplifier 61 inside the housing 11.

[0123] The power supply unit 100 has conductor layers 101, 102, 103 and pins 104, 105, 106, 107. The conductor layer 103 is an example of a first conductive part. The conductor layers 101, 102, 103 and the pins 104, 105, 106, 107 are made of a conductor such as copper.

[0124] The conductor layer 101 is provided on the PWB 51. The conductor layer 101 electrically connects between the respective electronic components mounted on the PWB 51. For example, the conductor layer 101 electrically connects the I / F connector 52, the controller 53, the servo controller 54, and the conversion device 81 to the relay connector 55.

[0125] The conductor layer 102 is provided on the FPC 19. The conductor layer 102 electrically connects, for example, the relay connector 62 to the conversion device 82. Furthermore, the conductor layer 102 electrically connects the relay connector 62 to the flexure 43. Thus, the relay connector 62 is electrically connected to the magnetic head 15 via the conductor layer 102 and the flexure 43.

[0126] The conductor layer 103 is provided on the relay FPC 70. The conductor layer 103 has Figure 5 the external terminal 103a and the internal terminal 103b as shown, and Figure 6 the extension part 103c as shown. As Figure 5 shown, the external terminal 103a is provided on the external part 75 of the relay FPC 70. The internal terminal 103b is provided on the internal part 76. The extension part 103c extends over the external part 75, the internal part 76, and the intermediate part 77, connecting the external terminal 103a and the internal terminal 103b.

[0127] The pin 104 is provided on the relay connector 55 and is connected to the conductor layer 101. The pin 105 is provided on the relay connector 62 and is connected to the conductor layer 102. The pin 106 is provided on the relay connector 71 and is connected to the external terminal 103a of the conductor layer 103. The pin 107 is provided on the relay connector 72 and is connected to the internal terminal 103b of the conductor layer 103. Thus, the conductor layer 103 electrically connects the pins 106 and 107 of the relay connectors 71 and 72.

[0128] Connected to each other through the relay connectors 55 and 71, the pins 104 and 106 are electrically connected to each other. Connected to each other through the relay connectors 62 and 72, the pins 105 and 107 are electrically connected to each other. Thus, the power supply unit 100 electrically connects the FPC 19 outside the housing 11 to the magnetic head 15 and the preamplifier 61 inside the housing 11.

[0129] The magnetic head 15 and the preamplifier 61 receive power supply from the electronic device 1 through the power supply unit 100 and the I / F connector 52. In other words, the magnetic head 15, the preamplifier 61, and the conversion devices 81 and 82 receive power supply from the PCB 50 through the relay connectors 55, 62, 71, and 72. In addition, the power supply unit 100 is not limited to power supply (power source), and may also have multiple wirings for grounding (Ground) or control. Furthermore, the power supply unit 100 may also have wirings for data communication between the components mounted on the FPC 19 and the PCB 50.

[0130] Hereinafter, an example of the operation of the HDD 10 of the present embodiment will be described. For example, in the writing operation, Figure 4 the processor 1b of the electronic device 1 inputs a write command and the data to be written to the controller 53 via the I / F connectors 1a and 52. The RWC of the controller 53 inputs a write signal corresponding to the data to be written to the conversion device 81 of the communication unit 80 based on the write command.

[0131] The conversion IC of the conversion device 81 converts the input write signal into a drive signal and outputs it to the light source. The light source of the conversion device 81 emits light corresponding to the drive signal toward the end 83a of the optical waveguide 83. In other words, the conversion device 81 emits light corresponding to the electrical signal (write signal) of the information written by the magnetic head 15 to the magnetic disk 12.

[0132] The optical waveguide 83 transmits the light incident on the end 83a to the end 83b. The optical waveguide 83 emits this light from the end 83b toward the light receiving element of the conversion device 82. That is, the optical waveguide 83 emits the light incident on the end 83a located outside the housing 11 from the end 83b located inside the housing 11.

[0133] When light is incident on the light receiving element of the conversion device 82, the light receiving element outputs an output signal corresponding to the light to the conversion IC. The conversion IC of the conversion device 82 converts (restores) the output signal into a write signal and outputs it to the preamplifier 61. In other words, the conversion device 82 generates an electrical signal (write signal) of the information written by the magnetic head 15 to the magnetic disk 12 corresponding to the light emitted by the conversion device 81.

[0134] The preamplifier 61 amplifies the write signal and outputs it to the magnetic head 15. The magnetic head 15 writes the data to be written included in the write signal to the storage layer of the magnetic disk 12.

[0135] Furthermore, Figure 4 the controller 53 controls various components such as the VCM 17 based on the write command. For example, based on the control from the controller 53, the servo controller 54 controls the VCM 17. The servo controller 54 outputs a signal to the VCM 17 through the power supply unit 100, for example. In addition, the servo controller 54 may output a signal to the VCM 17 through the communication unit 80.

[0136] On the other hand, in the read operation, the processor 1b of the electronic device 1 inputs a read command to the controller 53 via the I / F connectors 1a and 52. The controller 53 causes the magnetic head 15 to read data from the storage layer of the magnetic disk 12 based on the read command.

[0137] When the magnetic head 15 reads the data to be read, the preamplifier 61 amplifies the read signal corresponding to the read data and outputs it to the conversion IC of the conversion device 82. The conversion IC of the conversion device 82 converts the input read signal into a drive signal and outputs it to the light source. The light source of the conversion device 82 emits light corresponding to the drive signal toward the end 83b of the optical waveguide 83. In other words, the conversion device 82 emits light corresponding to the electrical signal (read signal) of the information read by the magnetic head 15 from the magnetic disk 12.

[0138] The optical waveguide 83 transmits the light incident on the end portion 83b to the end portion 83a. The optical waveguide 83 emits the light from the end portion 83a toward the light receiving element of the conversion device 81. That is, the optical waveguide 83 emits the light incident on the end portion 83b located inside the housing 11 from the end portion 83a located outside the housing 11.

[0139] When light is incident on the light receiving element of the conversion device 81, the light receiving element outputs an output signal corresponding to the light to the conversion IC. The conversion IC of the conversion device 81 converts (restores) the output signal into a read signal and outputs it to the controller 53. In this way, the conversion device 81 generates an electrical signal (read signal) corresponding to the light emitted from the conversion device 82 and the information read by the magnetic head 15 from the magnetic disk 12.

[0140] The RWC of the controller 53 demodulates the read signal and outputs the data to be read included in the read signal to the electronic device 1 through the I / F connectors 1a and 52. Thus, the electronic device 1 acquires the data read from the magnetic disk 12.

[0141] As described above, in the present embodiment, the controller 53, the conversion device 81, and the end portion 83a of the optical waveguide 83 are located outside the housing 11, and the preamplifier 61, the conversion device 82, and the end portion 83b of the optical waveguide 83 are located inside the housing 11. Moreover, the controller 53 outside the housing 11 and the preamplifier 61 inside the housing 11 communicate with each other through the conversion devices 81 and 82 and the optical waveguide 83.

[0142] In the operation of the HDD 10 described above, the data transmission and reception between the preamplifier 61 inside the housing 11 and the controller 53 outside the housing 11 are performed by wired communication based on the optical signal of the communication unit 80. On the other hand, the power supply to the magnetic head 15, the VCM 17, and the FPC 19 inside the housing 11 is performed by the power supply unit 100. Therefore, in the relay connectors 55, 62, 71, and 72, pins 104 to 107 for power supply are provided, but the pins for data transmission and reception can be omitted.

[0143] Pins for data transmission and reception can also be provided in the relay connectors 55, 62, 71, and 72. In this case, part of the data transmission and reception between the FPC 19 and the PWB 51 can be performed by wired communication based on the optical signal of the communication unit 80, and part of it can be performed by wired communication of the electrical signal through the relay connectors 55, 62, 71, and 72. For example, the transmission and reception of less data can be performed by wired communication of the electrical signal through the relay connectors 55, 62, 71, and 72.

[0144] In the HDD 10 of the first embodiment described above, the conversion device 81 emits light corresponding to an electrical signal. The conversion device 82 generates an electrical signal corresponding to the incident light. The optical waveguide 83 has an end portion 83a joined to the conversion device 81 and an end portion 83b joined to the conversion device 82, and transmits the light emitted from the conversion device 81 toward the conversion device 82. The controller 53 is electrically connected to the conversion device 81. The preamplifier 61 is electrically connected to the conversion device 82, and communicates with the controller 53 through the conversion device 81, the optical waveguide 83, and the conversion device 82. That is, the controller 53 and the preamplifier 61 transmit data through communication using light. Communication using light has a higher transmission capacity (bit rate) than communication using an electrical signal. Therefore, the HDD 10 can increase the transmission capacity and reduce the number of wirings compared to the case of transmitting data through communication using an electrical signal. For example, the controller 53 outside the housing 11 and the preamplifier 61 inside transmit data through communication using light, thereby reducing the number of wirings provided across the inside and outside of the housing 11. As a result, the HDD 10 can, for example, reduce the size of the slit 25c that connects the inside and outside of the housing 11, and can suppress the leakage of gas inside the housing 11 through the slit 25c.

[0145] Conventionally, for example, the relay substrate sometimes blocks the hole penetrating the bottom wall 25, and a connector for communication between the inside and outside of the housing 11 is provided on the relay substrate. As the storage capacity of the HDD 10 increases, the number of pins (wirings) of the connector may increase and the connector may become larger. When the connector becomes larger, the relay substrate may become larger, and gas leakage may occur through the fine holes of the relay substrate and the adhesive between the housing 11 and the relay substrate. Furthermore, the positioning accuracy of the connector may decrease, and the design cost for designing a new large connector may increase. On the other hand, as described above, the HDD 10 of the present embodiment can reduce the number of wirings. Therefore, the HDD 10 can, for example, miniaturize or omit the relay substrate and the connector, and further can suppress gas leakage, a decrease in the positioning accuracy between components, and an increase in the design cost.

[0146] The magnetic head 15 is located inside the housing 11 and is configured to read and write information with respect to the magnetic disk 12. The conversion device 81 emits light corresponding to an electrical signal (write signal) of the information written by the magnetic head 15 to the magnetic disk 12. In addition, the conversion device 82 emits light corresponding to an electrical signal (read signal) of the information read by the magnetic head 15 from the magnetic disk 12. The conversion device 82 generates a write signal corresponding to the light emitted from the conversion device 81. In addition, the conversion device 81 generates a read signal corresponding to the light emitted from the conversion device 82. That is, in the HDD 10, communication using light is used for the transmission of the write signal or the read signal. As a result, the HDD 10 can, for example, increase the access speed.

[0147] At least a part of the optical waveguide 83 is flexible. Thereby, the design freedom of the HDD 10 is increased. For example, by sandwiching the bent optical waveguide 83 between the conversion devices 81 and 82, the light sources and light receiving elements of the conversion devices 81 and 82 do not need to face each other.

[0148] At least a part of the optical waveguide 83 is provided on the relay FPC 70. Thereby, the design freedom of the HDD 10 is increased. For example, the relay FPC 70 can perform both optical transmission and electrical signal transmission or power supply through the optical waveguide 83 and the conductor layer 103 provided on the relay FPC 70.

[0149] The conversion device 81, the end portion 83a, and the controller 53 are located outside the housing 11. The conversion device 82, the end portion 83b, and the preamplifier 61 are located inside the housing 11. Thereby, the controller 53 outside the housing 11 and the preamplifier 61 inside transmit data through optical communication, thereby reducing the number of wirings provided across the inside and outside of the housing 11. Thus, the HDD 10 can, for example, reduce the size of the slit 25c that connects the inside and outside of the housing 11, and can suppress the leakage of gas inside the housing 11 through the slit 25c.

[0150] The relay FPC 70 has an external portion 75 located outside the housing 11, an internal portion 76 located inside the housing 11, and an intermediate portion 77 that penetrates the slit 25c provided in the housing 11 and is provided between the external portion 75 and the internal portion 76. At least a part of the optical waveguide 83 is provided on the relay FPC 70. Thereby, the HDD 10 does not require a relay substrate and can reduce the slit 25c. Thus, the HDD 10 can, for example, suppress the leakage of gas inside the housing 11. Furthermore, the HDD 10 can suppress a decrease in the positioning accuracy between components and an increase in the design cost.

[0151] The conductor layer 103 is provided on the relay FPC 70. The conductor layer 103 has an external terminal 103a provided on the external portion 75, an internal terminal 103b provided on the internal portion 76, and an extension portion 103c that connects the external terminal 103a and the internal terminal 103b. Thereby, the controller 53 outside the housing 11 can communicate with the preamplifier 61 inside the housing 11 using light through the optical waveguide 83 of the relay FPC 70, and can supply power through the conductor layer 103 of the relay FPC 70. Thereby, the components inside the housing 11 can be supplied with stable power through the conductor layer 103.

[0152] (Second Embodiment)

[0153] Hereinafter, with reference to Figure 7A description will be given of the second embodiment. In the descriptions of the following multiple embodiments, components having the same functions as the components already described are denoted by the same reference numerals as those of the already described components, and the descriptions may sometimes be omitted. In addition, the multiple components denoted by the same reference numerals are not limited to having all functions and properties in common, and may have different functions and properties corresponding to the respective embodiments.

[0154] Figure 7 This is an exemplary plan view schematically showing the FPC 19 of the second embodiment. As Figure 7 shown, in the second embodiment, the preamplifier 61 is provided in the second portion 19b of the FPC 19. Alternatively, the preamplifier 61 may be provided in the third portion 19c.

[0155] The second portion 19b is larger than the first portion 19a. Generally, when the storage capacity of the HDD 10 increases, for example, the number or size of the preamplifiers 61 and the number of wirings connected to the preamplifiers 61 increase. By mounting the preamplifier 61 in the relatively large second portion 19b, the wiring design in the FPC 19 becomes easier.

[0156] Furthermore, in the second embodiment, the HDD 10 has a communication unit 110. Similar to the communication unit 80, the communication unit 110 communicates using light between two components. The communication unit 110 communicates between the preamplifier 61 and the head 15. The preamplifier 61 and the head 15 are examples of the first component or the second component in the second embodiment.

[0157] The communication unit 110 has two conversion devices 111, 112 and an optical waveguide 113. The communication unit 110 may have a plurality of optical waveguides 113. The conversion devices 111, 112 are examples of the first conversion device or the second conversion device, respectively.

[0158] Similar to the conversion devices 81, 82, the conversion devices 111, 112 each have a light source, a light receiving element, and a conversion IC. Therefore, the conversion devices 111, 112 each emit light corresponding to an electrical signal and generate an electrical signal corresponding to the incident light. Alternatively, the conversion devices 111, 112 may be different from the conversion devices 81, 82.

[0159] The conversion devices 111, 112 are respectively mounted on the FPC 19. The conversion device 111 is electrically connected to the relay connector 62 and the conversion device 82 through the wiring of the FPC 19. The conversion device 112 is electrically connected to the flexure 43 through the wiring of the FPC 19. Therefore, the conversion device 112 is electrically connected to the head 15 through the flexure 43.

[0160] Similar to the optical waveguide 83, the optical waveguide 113 causes the light incident on the core layer to be totally reflected at the boundary surface between the core layer and the cladding layer and is transmitted. The optical waveguide 113 is provided on the FPC 19 and has flexibility. In addition, the optical waveguide 113 may be different from the optical waveguide 83.

[0161] The optical waveguide 113 has two end portions 113a and 113b. The end portions 113a and 113b are respectively an example of the first end portion or the second end portion. One end portion 113a is joined to the conversion device 111. The other end portion 113b is joined to the conversion device 112.

[0162] The optical waveguide 113 transmits the light emitted from one of the conversion devices 111 and 112 to the other. Between the conversion device 111 and the conversion device 112, a single optical waveguide 113 may be connected, or a plurality of optical waveguides included in the optical waveguide 113 may be connected.

[0163] In the communication unit 110, the conversion devices 111 and 112 convert an electrical signal into an optical signal, transmit the optical signal through the optical waveguide 113, and convert the optical signal into an electrical signal. Thus, the communication unit 110 can perform wired communication of the optical signal passing through the optical waveguide 113.

[0164] Via the above communication unit 110, the preamplifier 61 and the head 15 communicate with each other. In the present embodiment, the communication unit 110 transmits a read signal and a write signal between the preamplifier 61 and the head 15.

[0165] In the writing operation, the write signal output from the controller 53 is input to the preamplifier 61 through the communication unit 80. In addition, in the HDD 10 of the second embodiment, the communication unit 80 may be omitted, and the write signal may be input to the preamplifier 61 through the energization unit 100.

[0166] The preamplifier 61 amplifies the write signal and inputs it to the conversion device 111 of the communication unit 110. The conversion device 111 emits light corresponding to the write signal toward the end portion 113a of the optical waveguide 113.

[0167] The optical waveguide 113 transmits the light incident on the end portion 113a toward the end portion 113b. The optical waveguide 113 emits this light from the end portion 113b toward the light receiving element of the conversion device 112.

[0168] For example, as the actuator assembly 16 rotates, the optical waveguide 113 provided on the FPC 19 bends. However, even when the optical waveguide 113 bends together with the FPC 19, it can transmit light from the conversion device 111 to the conversion device 112.

[0169] When light is incident on the light-receiving element of the conversion device 112, the conversion device 112 generates a write signal corresponding to the light emitted from the conversion device 111. The conversion device 112 outputs the write signal to the magnetic head 15 through the flexible member 43. The magnetic head 15 writes the data to be written included in the write signal to the storage layer of the magnetic disk 12.

[0170] On the other hand, in the read operation, the magnetic head 15 outputs a read signal to the conversion device 112 through the flexible member 43 when reading the data to be read. The conversion device 112 emits light corresponding to the read signal toward the end 113b of the optical waveguide 113.

[0171] The optical waveguide 113 transmits the light incident on the end 113b toward the end 113a. The optical waveguide 113 emits the light from the end 113a toward the light-receiving element of the conversion device 111.

[0172] When light is incident on the light-receiving element of the conversion device 111, the conversion device 111 generates a read signal corresponding to the light emitted from the conversion device 112. The conversion device 111 outputs the read signal to the preamplifier 61 through the wiring of the FPC 19. The preamplifier 61 amplifies the read signal and outputs it to the controller 53 through, for example, the communication unit 80.

[0173] In the HDD 10 of the second embodiment described above, at least a part of the optical waveguide 113 is flexible. Thereby, the design freedom of the HDD 10 is increased. For example, the optical waveguide 113 can flexibly follow the relative movement between the housing 11 and the actuator assembly 16.

[0174] At least a part of the optical waveguide 113 is provided on the FPC 19. Thereby, the design freedom of the HDD 10 is increased. For example, the FPC 19 can perform both optical transmission and electrical signal transmission or power supply through the optical waveguide 113 and the wiring provided on the FPC 19.

[0175] The FPC 19 has a first portion 19a mounted on the actuator assembly 16, a second portion 19b mounted on the housing 11, and a flexible third portion 19c provided between the first portion 19a and the second portion 19b. The preamplifier 61 is provided in the second portion 19b or the third portion 19c. The size of the first portion 19a mounted on the actuator assembly 16 is limited by the size of the actuator assembly 16. Thus, for example, it is sometimes difficult to mount the preamplifier 61 on the first portion 19a and to provide wiring connected to the preamplifier 61 on the first portion 19a. On the other hand, the sizes of the second portion 19b and the third portion 19c are not limited by the size of the actuator assembly 16. Therefore, the degree of freedom in arranging the preamplifier 61 on the FPC 19 is increased, and further the degree of freedom in designing the HDD 10 is increased. On the other hand, when the preamplifier 61 is provided in the second portion 19b or the third portion 19c, the distance between the preamplifier 61 and the head 15 becomes longer. However, in the present embodiment, data transmission is performed between the preamplifier 61 and the head 15 by communication using light. Communication using light has less loss due to distance than communication using an electric signal. Thus, in the HDD 10, even if the distance between the preamplifier 61 and the head 15 becomes longer, it is possible to suppress loss in communication between the preamplifier 61 and the head 15.

[0176] (Third Embodiment)

[0177] Hereinafter, with reference to Figure 8 the third embodiment will be described. Figure 8 is an exemplary cross-sectional view schematically showing a part of the HDD 10 of the third embodiment. As Figure 8 shown, in the third embodiment, a through hole 25d is provided in the bottom wall 25 instead of the slit 25c. The through hole 25d is an example of the second through hole.

[0178] The through hole 25d penetrates the bottom wall 25 and opens on the inner surface 25a and the outer surface 25b. In other words, the through hole 25d communicates the accommodation space S with the outside of the housing 11. The through hole 25d is, for example, a substantially rectangular (quadrilateral) hole. Further, the shape of the through hole 25d is not limited to this example.

[0179] The HDD 10 of the third embodiment has a relay substrate 120 instead of the relay FPC 70. The relay substrate 120 is an example of the second wall. The relay substrate 120 is, for example, a substantially quadrilateral plate made of an insulator such as synthetic resin or ceramic. Further, the relay substrate 120 is not limited to this example. The relay substrate 120 has an inner surface 120a and an outer surface 120b.

[0180] The inner surface 120a is a substantially flat surface facing the inside of the housing 11. The inner surface 120a forms (defines, demarcates) a part of the storage space S inside the housing 11. The inner surface 120a faces components such as the FPC 19 disposed in the storage space S.

[0181] The outer surface 120b is located on the opposite side of the inner surface 120a and is a substantially flat surface facing the outside of the housing 11. The area of the outer surface 120b is larger than the opening area of the through-hole 25d. The outer surface 120b covers the through-hole 25d from the inside of the housing 11. A part of the outer surface 120b faces the inner surface 25a of the bottom wall 25. Another part of the outer surface 120b is exposed to the outside of the housing 11 through the through-hole 25d and faces the inner surface 51a of the PWB 51 through the through-hole 25d.

[0182] For example, an adhesive 121 is provided between the inner surface 25a of the bottom wall 25 and the outer surface 120b of the relay substrate 120 that face each other. The adhesive 121 fixes the inner surface 25a of the bottom wall 25 and the outer surface 120b of the relay substrate 120 to each other. The adhesive 121 contains, for example, a metal filler and can inhibit the passage of gas through the adhesive 121.

[0183] The adhesive 121 is provided along the edge of the through-hole 25d and fills the gap between the inner surface 25a of the bottom wall 25 and the outer surface 120b of the relay substrate 120 over the entire circumference. Thereby, the relay substrate 120 airtightly blocks the through-hole 25d. In addition, the relay substrate 120 can also be fixed to the bottom wall 25 by other methods such as soldering.

[0184] In the third embodiment, relay connectors 71 and 72 are provided on the relay substrate 120. The relay connector 71 protrudes from the outer surface 120b of the relay substrate 120 and is located outside the housing 11. The relay connector 72 protrudes from the inner surface 120a of the relay substrate 120 and is located in the storage space S inside the housing 11.

[0185] The relay connector 71 penetrates the through-hole 25d. Therefore, the sixth optical waveguide 96 and the pin 106 provided on the relay connector 71 penetrate the through-hole 25d. In addition, the sixth optical waveguide 96 and the pin 106 may be housed inside the through-hole 25d without penetrating the through-hole 25d. However, the optical waveguide 83 including the sixth optical waveguide 96 penetrates the through-hole 25d and is provided across the inside and outside of the housing 11. In addition, the energization portion 100 including the pin 106 penetrates the through-hole 25d and is provided across the inside and outside of the housing 11.

[0186] In the third embodiment, the communication unit 80 has an eighth optical waveguide 125 instead of the third optical waveguide 93. The eighth optical waveguide 125 is fixed to the relay substrate 120 in a state of penetrating the relay substrate 120.

[0187] For example, the eighth optical waveguide 125 is formed in a substantially rod shape. The eighth optical waveguide 125 penetrates a hole provided in the relay substrate 120 and is fixed to the relay substrate 120 by a synthetic resin or an adhesive. In addition, the eighth optical waveguide 125 is not limited to this example.

[0188] One end of the eighth optical waveguide 125 is joined to the sixth optical waveguide 96. For example, the relay connector 71 is fixed to the outer surface 120b of the relay substrate 120. Therefore, the eighth optical waveguide 125 is indirectly fixed to the sixth optical waveguide 96 via the relay substrate 120 and the relay connector 71. The eighth optical waveguide 125 is not limited to this example, and may be directly joined to the sixth optical waveguide 96, for example.

[0189] The other end of the eighth optical waveguide 125 is joined to the seventh optical waveguide 97. For example, the relay connector 72 is fixed to the inner surface 120a of the relay substrate 120. Therefore, the eighth optical waveguide 125 is indirectly fixed to the seventh optical waveguide 97 via the relay substrate 120 and the relay connector 72. The eighth optical waveguide 125 is not limited to this example, and may be directly joined to the seventh optical waveguide 97, for example.

[0190] In the third embodiment, the energizing unit 100 has a through-conductor 126 instead of the conductor layer 103. The through-conductor 126 includes a via (hole), for example. The through-conductor 126 penetrates the relay substrate 120 and is connected to the pins 106 and 107.

[0191] In the HDD 10 of the third embodiment described above, a part of the optical waveguide 83 is provided on the relay connector 71 located outside the housing 11 and the relay connector 72 located inside the housing 11. The housing 11 has a bottom wall 25 provided with a through-hole 25d. The optical waveguide 83 penetrates the through-hole 25d. That is, in the optical waveguide 83, a connection structure using a connector is provided between the conversion device 81 and the conversion device 82. Thus, compared with the case where a single optical waveguide 83 is directly joined to the conversion device 81 and the conversion device 82, the optical waveguide 83 can easily communicatively connect the conversion devices 81 and 82 separately disposed inside and outside the housing 11 by using the relay connectors 71 and 72.

[0192] The energization part 100 penetrates through the through-hole 25d. A part of the energization part 100 is provided in the relay connectors 71 and 72. Thus, components outside the housing 11 can communicate with components inside using light via the relay connectors 71 and 72 and the optical waveguide 83, and power can be supplied via the energization part 100. Thus, components inside the housing 11 can be supplied with stable power via the relay connectors 71 and 72.

[0193] The relay substrate 120 closes the through-hole 25d. The relay connector 71 located outside the housing 11 and the relay connector 72 located inside the housing 11 are provided on the relay substrate 120. The optical waveguide 83 penetrates through the relay substrate 120. For example, with the relay connectors 71 and 72 mounted on the relay substrate 120, the relay substrate 120 is mounted on the bottom wall 25. Thus, the relay connectors 71 and 72 can be easily mounted on the housing 11.

[0194] (Fourth Embodiment)

[0195] Hereinafter, Figure 9 the fourth embodiment will be described. Figure 9 is an exemplary cross-sectional view schematically showing a part of the HDD 10 of the fourth embodiment. As Figure 9 shown, in the HDD 10 of the fourth embodiment, the relay substrate 120 is omitted from the HDD 10 of the third embodiment.

[0196] The relay connector 71 of the fourth embodiment has a connection part 131 and a through part 132. The connection part 131 protrudes from the outer surface 25b of the bottom wall 25 and is located outside the housing 11. The connection part 131 is connected to the relay connector 55. The through part 132 extends from the connection part 131 and penetrates through the through-hole 25d. A part of the through part 132 protrudes from the inner surface 25a of the bottom wall 25.

[0197] The relay connector 71 is fixed to the bottom wall 25 by an adhesive 135, for example. The adhesive 135 fixes the connection part 131 to the outer surface 25b of the bottom wall 25. Further, the adhesive 135 is filled between the through part 132 and the inner surface of the through-hole 25d. The adhesive 135 contains a metal filler, for example, and can inhibit the passage of gas through the adhesive 135. Thus, the adhesive 135 hermetically seals the through-hole 25d.

[0198] The relay connector 72 of the fourth embodiment is mounted on the through part 132 of the relay connector 71. For example, the relay connector 72 is mounted on the through part 132 by a snap. Also, the relay connector 72 can be fixed to the inner surface 25a of the bottom wall 25 by an adhesive.

[0199] The relay connector 72 is installed in the through-hole portion 132, whereby the sixth optical waveguide 96 provided in the relay connector 71 and the seventh optical waveguide 97 provided in the relay connector 72 are joined to each other. Further, the pins 106 and 107 provided in the relay connectors 71 and 72 are connected to each other.

[0200] The relay connector 71 of the fourth embodiment is installed on the bottom wall 25, for example, by inserting the through-hole portion 132 into the through-hole 25d. Further, the relay connector 72 is installed on the through-hole portion 132 protruding from the inner surface 25a of the bottom wall 25 by a snap. Thus, the relay connectors 71 and 72 can be easily installed on the bottom wall 25.

[0201] In the above description, the connection portion 131 and the through-hole portion 132 are provided in the relay connector 71. However, the relay connector 72 may also have the connection portion 131 and the through-hole portion 132. In this case, the relay connector 71 is installed in the through-hole portion 132 of the relay connector 72.

[0202] In the HDD0 of the fourth embodiment described above, one of the relay connectors 71 and 72 has the connection portion 131 located outside the through-hole 25d and the through-hole portion 132 passing through the through-hole 25d. The other of the relay connectors 71 and 72 is installed in the through-hole portion 132. Thus, the HDD10, for example, does not require the relay substrate 120 and can reduce the through-hole 25d. Therefore, the HDD10 can suppress the leakage of gas inside the housing 11 through the through-hole 25d.

[0203] In the above-described multiple embodiments, the optical waveguide 83 is provided across the inside and outside of the housing 11, and the optical waveguide 113 is provided inside the housing 11. The HDD10 is not limited to this example and may also have an optical waveguide provided outside the housing 11. For example, the HDD10 may also have an optical waveguide provided on the PWB51.

[0204] According to at least one embodiment described above, the disc device includes a first conversion device, a second conversion device, an optical waveguide, a first component, and a second component. The first conversion device emits light corresponding to an electrical signal. The second conversion device generates an electrical signal corresponding to the incident light. The optical waveguide has a first end joined to the first conversion device and a second end joined to the second conversion device, and transmits the light emitted by the first conversion device to the second conversion device. The first component is electrically connected to the first conversion device. The second component is electrically connected to the second conversion device, and the first conversion device communicates with the first component through the optical waveguide and the second conversion device. That is, the first component and the second component transmit data through optical communication. Optical communication has a higher transmission capacity (bit rate) than electrical signal communication. Therefore, the disc device can increase the transmission capacity and reduce the number of wirings compared to the case of transmitting data through electrical signal communication. For example, components outside the housing and components inside the housing transmit data through optical communication, thereby reducing the number of wirings provided across the inside and outside of the housing. As a result, the disc device can, for example, reduce the size of the through holes that connect the inside and outside of the housing and the walls that block the through holes, and can suppress the leakage of gas inside the housing through the through holes and the walls.

[0205] In the above description, suppression is defined, for example, as preventing the occurrence of a phenomenon, action, or influence, or reducing the degree of a phenomenon, action, or influence. In addition, in the above description, restriction is defined, for example, as preventing movement or rotation, or allowing movement or rotation within a specified range and preventing movement or rotation exceeding the specified range.

[0206] Several embodiments of the present invention have been described, but these embodiments are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Claims

1. A disc device includes: a first conversion device that emits light corresponding to an electrical signal; a second conversion device that generates an electrical signal corresponding to the incident light; an optical waveguide having a first end joined to the first conversion device and a second end joined to the second conversion device, and transmitting the light emitted by the first conversion device to the second conversion device; a first component electrically connected to the first conversion device; a second component electrically connected to the second conversion device, and communicating with the first component through the first conversion device, the optical waveguide, and the second conversion device; a housing; a disc-shaped recording medium located inside the housing and having a recording layer; a magnetic head located inside the housing and configured to read and write information with respect to the recording medium; a first flexible printed circuit board; an actuator that moves the magnetic head; and an amplifier that amplifies an electrical signal, wherein the first conversion device emits light corresponding to one of an electrical signal of information written by the magnetic head to the recording medium and an electrical signal of information read by the magnetic head from the recording medium, the second conversion device generates the one of the electrical signal of information written by the magnetic head to the recording medium and the electrical signal of information read by the magnetic head from the recording medium corresponding to the light emitted by the first conversion device, at least a part of the optical waveguide is flexible, at least a part of the optical waveguide is provided on the first flexible printed circuit board, the first flexible printed circuit board has a first part mounted on the actuator, a second part mounted on the housing, and a flexible third part provided between the first part and the second part, the amplifier is provided on the second part or the third part, one of the first component and the second component has the amplifier, and the other of the first component and the second component has the magnetic head.

2. A disc device includes: a first conversion device that emits light corresponding to an electrical signal; a second conversion device that generates an electrical signal corresponding to the incident light; an optical waveguide having a first end portion joined to the first conversion device and a second end portion joined to the second conversion device, and transmitting the light emitted from the first conversion device to the second conversion device; a first component electrically connected to the first conversion device; a second component electrically connected to the second conversion device, and communicating with the first component through the first conversion device, the optical waveguide, and the second conversion device; a housing; a disc-shaped recording medium located inside the housing and having a recording layer; and a magnetic head located inside the housing and configured to read and write information with respect to the recording medium. The first conversion device emits light corresponding to one of the electrical signals of the information written by the magnetic head to the recording medium and the electrical signal of the information read by the magnetic head from the recording medium. The second conversion device generates the electrical signal corresponding to the light emitted from the first conversion device, which is one of the electrical signals of the information written by the magnetic head to the recording medium and the electrical signal of the information read by the magnetic head from the recording medium. One of the first conversion device, the first end portion and the first component, and the second conversion device, the second end portion and the second component is located outside the housing, and the other of the first conversion device, the first end portion and the first component, and the second conversion device, the second end portion and the second component is located inside the housing. The disc device further includes a second flexible printed circuit board having an external portion located outside the housing, an internal portion located inside the housing, and an intermediate portion passing through a first through hole formed in the housing and provided between the external portion and the internal portion, and at least a part of the optical waveguide is provided on the second flexible printed circuit board.

3. The disc device according to claim 2, wherein, The disc device further includes a first conductive portion provided on the second flexible printed circuit board, having an inner terminal provided on the internal portion, an outer terminal provided on the external portion, and an extension portion connecting the inner terminal and the outer terminal.

4. The disc device according to claim 2, further includes: a first connector located outside the housing and provided with a part of the optical waveguide; and a second connector located inside the housing and provided with a part of the optical waveguide. The housing has a first wall provided with a second through hole, and the optical waveguide passes through the second through hole.

5. The disk device according to claim 4, wherein, The disc device further includes a second conductive portion passing through the second through hole, and a part of the second conductive portion is provided on the first connector and the second connector.

6. The disk device according to claim 4 or 5, wherein, The disc device further includes a second wall closing the second through hole, and the first connector and the second connector are provided on the second wall, and the optical waveguide passes through the second wall.

7. The disc apparatus according to claim 4 or 5, wherein, One of the first connector and the second connector has a connection part located outside the second through hole and a through part passing through the second through hole, and the other of the first connector and the second connector is mounted on the through part.

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