Suspension assembly and disc device

Abstract

Provided are a suspension assembly capable of maintaining the strength of connection terminals and seeking to narrow the pitch of wiring and improve the jointability of the connection terminals, and a disc device provided with the same. According to an embodiment, the suspension assembly is provided with a support plate, a head supported by the support plate, and a wiring member provided to the support plate. The wiring member has a front end portion electrically connected to the head, a connection end portion extending out to the outside of the support plate, and a plurality of wirings extending between the front end portion and the connection end portion. The connection end portion is provided with a cover layer provided with an opening, 13 or more connection terminals arranged in alignment with the opening leaving a space in the length direction of the opening and connected to the wirings, respectively, and a base layer provided in overlapping relation to the cover layer and the connection terminals and having a plurality of first openings facing a portion of the connection terminals, respectively, and a plurality of second openings facing the space between adjacent connection terminals, respectively.

Description

[0001] This application claims priority to Japanese Patent Application No. 2022-021348 (Filing Date: February 15, 2022). This application incorporates the entire contents of the base application by reference thereto. TECHNICAL FIELD

[0002] Embodiments of the present application relate to a suspension assembly used in a disk device and a disk device provided with the same. BACKGROUND

[0003] As a disk device, for example, a magnetic disk device generally has a magnetic disk provided in a base, a spindle motor that supports and rotationally drives the magnetic disk, and a head actuator. The head actuator has a plurality of suspension assemblies each of which supports a magnetic head. Each of the suspension assemblies has a suspension that is attached to a front end portion of an arm of the head actuator, and a wiring member (flexible member, wiring trace) that is provided to the suspension. The magnetic head is supported at a gimbal portion of the wiring member, and a head suspension assembly is configured. A plurality of connection terminals are provided at a connection end portion of the wiring member. These connection terminals are electrically connected to the magnetic head via wiring of the wiring member. Further, the connection terminals of the connection end portion are soldered and joined to connection pads of a flexible printed wiring board (FPC) provided to the actuator block.

[0004] In recent years, in a magnetic disk device, in order to further increase the density and reliability, researches have been conducted to add a HDI (head disk interface) sensor, a multi-stage actuator, a DFH (dynamic flying height) control function, a high-frequency assisted recording or a heat-assisted recording function, and the like to the head or the suspension assembly. Along with this, it is necessary to further increase the number of wirings of the wiring member and the number of connection terminals provided to the connection end portion.

[0005] In order to secure an area in which a plurality of wirings are arranged, it is necessary to reduce the wiring width and to wind the wiring at a narrow pitch. In addition, in order to narrow the pitch, it is necessary to thin the thickness of the wiring, but if the wiring is thinned, the connection terminal (flying-lead) formed in the same layer as the wiring also becomes thin, and the strength thereof decreases. SUMMARY

[0006] Embodiments of the present application are to provide a suspension assembly that can maintain the strength of the connection terminal and seek to narrow the pitch of the wiring and improve the joining property of the connection terminal, and a disk device provided with the same.

[0007] According to an embodiment, a suspension assembly includes a support plate, a head supported to the support plate, and a wiring member provided to the support plate. The wiring member has a front end portion electrically connected to the head, a connection end portion extending to an outer side of the support plate, and a plurality of wirings extending between the front end portion and the connection end portion. The connection end portion includes a cover layer provided with an opening having a predetermined length, 13 or more connection terminals arranged at intervals in a length direction of the opening and connected to the wirings, respectively, and a base layer provided to overlap the cover layer and the connection terminals and having a plurality of first openings facing the connection terminals, respectively, and a plurality of second openings facing spaces between the adjacent connection terminals, respectively. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is an exploded perspective view of a hard disk drive (HDD) according to a first embodiment.

[0009] Figure 2 is a perspective view showing an actuator assembly and a substrate unit (FPC unit) of the HDD.

[0010] Figure 3 is a perspective view showing a suspension assembly of the actuator assembly.

[0011] Figure 4 is a side view showing an actuator block of the actuator assembly, a joint portion (FPC joint portion) of the FPC unit, and a tail connection end portion of a flexure.

[0012] Figure 5 is a side view of the joint portion of the FPC unit.

[0013] Figure 6 is a cross-sectional view of the flexure.

[0014] Figure 7 is a plan view of the tail connection end portion of the flexure.

[0015] Figure 8 is a plan view showing a part of the tail connection end portion enlarged.

[0016] Figure 9 is a cross-sectional view of the tail connection end portion along a line A-A of Figure 8 .

[0017] Figure 10 is a cross-sectional view of the tail connection end portion along a line B-B of Figure 8 .

[0018] Figure 11 (a) of is a cross-sectional view showing a state where the tail connection end portion is arranged to overlap the joint portion,Figure 11 (b) is a sectional view of the tail connecting end portion and the joint portion after the joint by the solder.

[0019] Figure 12 (a) is a plan view schematically showing a connection pad, a solder, and an insulating layer of the joint portion of the HDD of the second embodiment, Figure 12 (b) is a sectional view of the tail connecting end portion and the joint portion after the joint by the solder.

[0020] Figure 13 is a plan view showing a part of the tail connecting end portion in the HDD of the third embodiment.

[0021] Figure 14 is a plan view showing a connection end portion of a flexible member used in the HDD of the fourth embodiment.

[0022] Explanation of Reference Numerals

[0023] 10... housing, 12... base, 12a... bottom wall, 12b... side wall, 14... top cover, 18... disk, 17... head, 19... spindle motor, 21... FPC unit, 22... actuator assembly, 30... suspension assembly, 48... flexible member (wiring member), 48c... connection end portion (tail connecting end portion), 50... connection terminal, 64... joint portion, 68a... base insulating layer, 68b... conductive layer, 68c... cover insulating layer, 72... connection pad group, 73... connection pad, 90... opening, OP1... first opening, OP2... second opening DETAILED DESCRIPTION

[0024] Hereinafter, a disk device of an embodiment will be described with reference to the drawings.

[0025] Further, the disclosure is nothing but an example, and appropriate changes that can be easily thought of by those skilled in the art while maintaining the gist of the invention are of course included in the scope of the invention. In addition, the drawings exist to represent, in a schematic manner, the width, thickness, shape, and the like of each portion compared to the actual form in order to make the description clearer, but are nothing but an example and do not limit the explanation of the invention. In addition, in the present specification and each drawing, the same reference numerals are attached to elements that are the same as those described with respect to the already appearing drawings, and detailed description is sometimes appropriately omitted.

[0026] (First Embodiment)

[0027] As a disk device, a hard disk drive (HDD) of the first embodiment will be described in detail.

[0028] Figure 1 is an exploded perspective view of the HDD of the first embodiment shown with the top cover removed.

[0029] The HDD has a case 10 of a flat, substantially rectangular shape. The case 10 has a rectangular box-shaped base 12 with an upper surface opening and a top cover 14. The base 12 has a rectangular-shaped bottom wall 12a facing the top cover 14 with a gap therebetween and a plurality of side walls 12b standing up along the periphery of the bottom wall 12a, for example, integrally formed of aluminum. The top cover 14 is formed of, for example, stainless steel in a rectangular plate shape. The top cover 14 is threadedly fastened to the side walls 12b of the base 12 by a plurality of screws 13 to close the upper portion opening of the base 12.

[0030] A plurality of magnetic disks 18 as recording media and a spindle motor 19 as a driving unit to support the magnetic disks 18 and rotate the magnetic disks 18 are provided in the case 10. The spindle motor 19 is disposed on the bottom wall 12a. Each of the magnetic disks 18 is formed in a circular plate shape, for example, with a diameter of 96 mm (3.5 inches), and has a substrate formed of a non-magnetic material, for example, glass or aluminum, and a magnetic recording layer formed on the upper surface and / or the lower surface of the substrate. The magnetic disks 18 are fitted on an unillustrated hub of the spindle motor 19 coaxially and fixed to the hub by clamping springs 20. The magnetic disks 18 are supported in a state of being positioned in parallel with the bottom wall 12a of the base 12. The plurality of magnetic disks 18 are rotated at a predetermined rotational speed by the spindle motor 19. In the present embodiment, for example, five magnetic disks 18 are housed in the case 10, but the number of the magnetic disks 18 is not limited thereto.

[0031] A plurality of magnetic heads 17 to record and reproduce information on the magnetic disks 18, an actuator assembly (carriage assembly) 22 to support the magnetic heads 17 in a manner to be movable relative to the magnetic disks 18 are provided in the case 10. In addition, a voice coil motor (hereinafter referred to as VCM) 24 to rotate and position the actuator assembly 22, a ramp loading mechanism 25 to hold the magnetic heads 17 at an unloading position separated from the magnetic disks 18 when the magnetic heads 17 are moved to the outermost periphery of the magnetic disks 18, and a substrate unit (FPC unit) 21 on which electronic components such as a conversion connector are mounted are provided in the case 10. The actuator assembly 22 and the VCM 24 constitute a head actuator.

[0032] The actuator assembly 22 has an actuator block 29 supported in a manner to be rotatable about a support shaft 26 via a bearing unit 28, a plurality of arms 32 extending from the actuator block 29, and a suspension assembly 30 extending from each of the arms 32. The magnetic head 17 is supported at a front end portion of each of the suspension assemblies 30. The support shaft 26 is standingly provided on the bottom wall 12a. The magnetic head 17 includes a read head, a write head, an auxiliary element, a heater, and the like.

[0033] An unillustrated printed circuit substrate is threadedly fastened to the outer surface of the bottom wall 12a of the base 12. The printed circuit substrate constitutes a control unit to control the operation of the spindle motor 19 and the operation of the VCM 24 and the magnetic head 17 via the substrate unit 21.

[0034] Figure 2 is a perspective view showing the actuator assembly and the FPC unit, Figure 3 is a perspective view showing the suspension assembly. As shown in Figure 2 , the actuator assembly 22 is provided with an actuator block 29 having a through-hole 31, a bearing unit (unit bearing) 28 disposed in the through-hole 31, a plurality of, for example, six arms 32 extending from the actuator block 29, a suspension assembly 30 mounted to each of the arms 32, and a magnetic head 17 supported by the suspension assembly 30. The actuator block 29 is supported by the bearing unit 28 in a manner that it is rotatable about a support shaft (pivot shaft) 26 erected on a bottom wall 12a.

[0035] In the present embodiment, the actuator block 29 and the six arms 32 are integrally formed of aluminum or the like, constituting a so-called E-block. The arms 32 are formed, for example, in an elongated flat plate shape, and extend from the actuator block 29 in a direction orthogonal to the support shaft 26. The six arms 32 are disposed in parallel with a gap therebetween.

[0036] The actuator assembly 22 has a support frame 36 extending from the actuator block 29 in a direction opposite to the arms 32, and the voice coil 34 is supported by the support frame 36. As shown in Figure 1 , the voice coil 34 is located between a pair of yokes 38 of which one is fixed to the base 12, and constitutes the VCM 24 together with these yokes 38 and a magnet fixed to either yoke.

[0037] The actuator assembly 22 is provided with ten suspension assemblies 30 each of which supports the magnetic head 17, and these suspension assemblies 30 are mounted to the front end portions 32a of the respective arms 32. The plurality of suspension assemblies 30 include upward head suspension assemblies that support the magnetic heads 17 upward, and downward head suspension assemblies that support the magnetic heads 17 downward. These upward head suspension assemblies and downward head suspension assemblies are constituted by arranging the same configuration of the suspension assembly 30 upside down.

[0038] In the present embodiment, in Figure 2 , the upward head suspension assembly 30 is mounted to the uppermost arm 32, and the downward head suspension assembly 30 is mounted to the lowermost arm 32. The upward head suspension assembly 30 and the downward head suspension assembly 30 are each mounted to the four intermediate arms 32.

[0039] As shown in Figure 3 , the suspension assembly 30 has a base plate 44 of a substantially rectangular shape, a load beam 46 of an elongated plate spring shape, and a flexible member (wiring member) 48 of an elongated band shape. The base end portion of the load beam 46 is fixed to the end portion of the base plate 44 with an overlap. The load beam 46 extends from the base plate 44, and is formed in a taper toward the extended end. The base plate 44 and the load beam 46 are formed, for example, of stainless steel, constituting a support plate (suspension).

[0040] The base plate 44 has a circular opening at its base end portion and a circular ring-shaped protrusion 51 around the opening. The base plate 44 is fastened and joined to the front end portion 32a of the arm 32 by fitting the protrusion 51 of the base plate 44 into the rivet hole 40 formed in the front end portion 32a of the arm 32 and riveting the protrusion 51 (see FIG. 2). Figure 2 The base end portion of the load beam 46 is arranged so as to overlap the front end portion of the base plate 44, and is fixed to the base plate 44 by welding.

[0041] The flexible member 48 of the suspension assembly 30 has a metal plate (a liner layer) of stainless steel or the like as a base and a flexible printed wiring board (FPC) provided on the metal plate, and forms an elongated and band-shaped laminated plate.

[0042] The flexible member 48 has a front end side portion 48a and a base end side portion 48b. The front end side portion 48a is mounted to the load beam 46 and the base plate 44. The base end side portion 48b extends outward from the side edge of the base plate 44, and extends along the arm 32 to the base end portion (the actuator block 29) of the arm 32.

[0043] The flexible member 48 has a front end portion on the load beam 46 and a gimbal portion (an elastic support portion) 52 formed at the front end portion. The magnetic head 17 is mounted to the gimbal portion 52. In addition, a pair of piezoelectric elements 53 constituting a micro actuator are mounted to the gimbal portion 52, and are arranged on both sides of the magnetic head 17. The front end portion of the flexible member 48 is electrically connected to the read head element, the write head element, the heater, the auxiliary element, the HDI sensor, other components, and the piezoelectric elements 53 of the magnetic head 17 via wires, connection pads, and the like, which are not shown.

[0044] The flexible member 48 has a connection end portion (a tail connection end portion) 48c provided at one end of the base end side portion 48b. The connection end portion 48c is formed in an elongated rectangular shape. The connection end portion 48c is bent at a substantially right angle with respect to the base end side portion 48b, and is located at a position substantially perpendicular to the arm 32. A plurality of, for example, 13 connection terminals (connection pads) 50 are provided at the connection end portion 48c. These connection terminals 50 are respectively connected to the wires of the flexible member 48. That is, the plurality of wires of the flexible member 48 extend over substantially the entire length of the flexible member 48, one end is electrically connected to the magnetic head 17, and the other end is connected to the connection terminals (connection pads) 50 of the connection end portion 48c.

[0045] As shown in FIG. 2, the base plate 44 is fastened and joined to the front end portion 32a of the arm 32 by fitting the protrusion 51 of the base plate 44 into the rivet hole 40 formed in the front end portion 32a of the arm 32 and riveting the protrusion 51. Figure 2As shown, 10 suspension assemblies 30 extend from 6 arms 32, are arranged in a substantially parallel manner to each other, and are arranged with a predetermined interval. These suspension assemblies 30 constitute 5 downward head suspension assemblies and 5 upward head suspension assemblies. The downward head suspension assemblies 30 and the upward head suspension assemblies 30 of each group are positioned in parallel to each other with a predetermined interval, and the magnetic heads 17 are positioned to face each other. These magnetic heads 17 are positioned to face both surfaces of the corresponding magnetic disk 18.

[0046] As shown, the FPC unit 21 integrally has a base portion 60 of a substantially rectangular shape, an elongated band-shaped relay portion 62 extending from one side edge of the base portion 60, and a substantially rectangular-shaped joint portion (FPC joint portion) 64 provided continuously to the front end portion of the relay portion 62. These base portion 60, relay portion 62, and joint portion 64 are formed of a flexible printed wiring substrate (FPC). Figure 2

[0047] On one surface (outer surface) of the base portion 60, a conversion connector, a plurality of capacitors 63, and the like, which are not shown, are mounted as electronic components, and are electrically connected to a wiring which is not shown. On the other surface (inner surface) of the base portion 60, two metal plates 70 and 71, which function as reinforcing plates, are respectively attached. The base portion 60 is arranged on the bottom wall 12a of the housing 10, and is threadedly fastened to the bottom wall 12a by two screws. The conversion connector on the base portion 60 is connected to a control circuit substrate provided on the bottom surface side of the housing 10.

[0048] The relay portion 62 extends from the base portion 60 toward the actuator assembly 22. The joint portion 64 provided on the extended end of the relay portion 62 is formed in a rectangular shape having a height and a width substantially equal to those of the side surface (mounting surface) of the actuator block 29. The joint portion 64 is attached to the mounting surface of the actuator block 29 via a gasket plate formed of aluminum or the like, and is threadedly fastened and fixed to the mounting surface by a fixing screw.

[0049] The connection end portions 48c of the 10 flexible members 48 are connected to a plurality of connection portions of the joint portion 64, and are electrically connected to the wiring of the joint portion 64. The plurality of connection end portions 48c are arranged in a direction parallel to the support shaft 26. A head IC (head amplifier) 54 is mounted on the joint portion 64, and is connected to the connection end portions 48c and the base portion 60 via the wiring of the FPC. Further, the joint portion 64 has a pair of connection pads 55 to which the voice coil 34 is connected.

[0050] The 10 magnetic heads 17 of the actuator assembly 22 are electrically connected to the base portion 60 via the wiring of the flexible member 48, the connection end portion 48c, the joint portion 64, the relay portion 62, and the base portion 60 of the FPC unit 21. Further, the base portion 60 is electrically connected to the printed circuit substrate on the bottom surface side of the housing 10 via the conversion connector. ​

[0051] The wiring configuration of the joint portion 64 will be described in detail. Figure 4 is a side view showing the joint portion 64 and the plurality of connection end portions mounted to the actuator block, Figure 5 is a side view showing the joint portion 64 before joining the connection end portions.

[0052] As shown in Figure 5 , the joint portion 64 has ten connection pad groups 72 corresponding to the connection end portions 48c of the suspension assembly 30. Each connection pad group 72 has a plurality of, for example, 13 connection pads 73 arranged in one column, each of which is electrically connected to the head IC 54 or the base portion 60 via a wire. The 13 connection pads 73 of each connection pad group 72 are arranged in one column with a predetermined interval from each other in a direction substantially parallel to the arm 32. In addition, the ten connection pad groups 72 are arranged in parallel to each other with a predetermined interval in a direction parallel to the support shaft 26, that is, in a height direction of the actuator block 29. These connection pads 73 are located within a strip-shaped opening 76 formed in a cover insulating layer of the FPC to be exposed to the outside via the opening. In addition, in a state before joining the connection end portions 48c, a solder layer 78 is formed on each connection pad 73.

[0053] As shown in Figure 4 and Figure 5 , the joint portion 64 of the FPC is fixed to the arrangement surface of the actuator block 29 via a backing plate. The connection end portions 48c of the flexure 48 are arranged so as to overlap each connection pad group 72 of the joint portion 64. The connection terminals 50 of the connection end portions 48c abut against the corresponding connection pads 73 via the solder layer 78, respectively. As will be described later, by melting the solder layer 78 using laser irradiation, each connection terminal 50 and the corresponding connection pad 73 are mechanically and electrically solder-joined.

[0054] Next, the structure of the flexure 48 and the detailed structure of the connection end portions 48c will be described.

[0055] Figure 6 is a cross-sectional view showing the laminated structure of the flexure 48, Figure 7 is a plan view showing the connection end portions of the flexure in an enlarged manner.

[0056] As shown in Figure 6As shown, the flexible member 48 has a metal plate (a liner layer) 80 of stainless steel or the like that becomes a base layer, and a flexible printed wiring board (FPC) 82 formed on the metal plate. In this embodiment, an adhesive layer (a thermal insulation layer) 84 is provided between the metal plate 80 and the FPC 82. In addition, the FPC 82 is composed of a laminate of a base insulating layer 86a, a conductive layer 86b laminated on the base insulating layer 86a, and a cover insulating layer (a protective layer) 86c laminated so as to overlap the base insulating layer 86a and the conductive layer 86b. The base insulating layer 86a and the cover insulating layer 86c are formed of, for example, polyimide. The conductive layer 86b is formed of, for example, a copper foil, and is composed of a plurality of wirings, connection terminals, and connection pads by patterning the copper foil. The film thickness of the conductive layer (copper foil) 86b is formed to be, for example, 9 μm or less. Further, the FPC 82 is not limited to a single layer structure, and a FPC having a multilayer structure of a plurality of conductive layers and a plurality of cover insulating layers can also be used. In addition, the adhesive layer (thermal insulation layer) 84 can be omitted.

[0057] As shown in FIG. 6, the connection end portion 48c of the flexible member 48 is formed in a substantially elongated rectangular shape having a length LI and a width Wl. Figure 7 As shown in FIG. 6, the connection end portion 48c of the flexible member 48 is formed in a substantially elongated rectangular shape having a length LI and a width Wl. Figure 7 In FIG. 6, the lowermost layer indicates the cover insulating layer 86c, and the uppermost layer indicates the metal plate 80. The cover insulating layer 86c side abuts against the engaging portion 64 of the FPC unit.

[0058] The cover insulating layer 86c has a rectangular-shaped opening 90 formed in a central portion thereof. The opening 90 is formed, for example, to have a length L2 of 6 mm or less in the length direction and a width W2 of 0.5 mm. The 13 connection terminals 50 described above are respectively arranged so as to face the opening 90, and are arranged with a space left in the length direction of the opening 90. Each connection terminal 50 has, for example, a rectangular shape, and extends from one end to the other end in the width direction of the cover insulating layer 86c. A central portion (a hanging lead) of the connection terminal 50 in the length direction faces the opening 90, and both end portions of the connection terminal 50 in the length direction are positioned so as to overlap the cover insulating layer 86c.

[0059] In the cover insulating layer 86c, a plurality of wirings S are divided into two and provided in regions on both sides in the width direction of the opening 90. Each connection terminal 50 is connected to the wirings S. Thus, the 13 connection terminals 50 are electrically connected to the connection pads of the front end portion of the flexible member 48 via the wirings S.

[0060] The base insulating layer 86a is provided so as to overlap the entire surface of the lid insulating layer 68c and the 13 connection terminals 50, the wiring S. The metal plate 80 has a substantially rectangular opening 91 formed in the center portion thereof. The opening 91 is formed to have a length and a width that are sufficiently larger than those of the opening 90 of the lid insulating layer 68c. Thus, the metal plate 80 covers the outer peripheral portion of the connection end portion 48c and the base end portion.

[0061] Figure 8 is an enlarged plan view of a portion of the connection end portion 48c. As shown in Figure 7 and Figure 8 The width (the interval between the pair of side edges) WT of the central portion of each connection terminal 50 facing the opening 90 of the lid insulating layer 68c is, for example, 0.2 mm. The interval WS between the connection terminals 50 is set to be 0.15 mm or more. The interval WS or a gap is provided between the one end of the length direction of the opening 90 and the connection terminal 50 and between the other end of the length direction of the opening 90 and the connection terminal 50.

[0062] The interval between the connection terminals 50 can be set to be uniform, but in the present embodiment, a wide interval (for example, 0.3 mm) is provided every three connection terminals 50 from the side of the extended end of the connection end portion 48c. These wide interval portions are provided in order to provide a jig at the time of soldering the connection terminals 50.

[0063] A through-hole 50a is provided in the central portion of each connection terminal 50. The through-hole 50a has, in one example, a substantially rectangular shape. The width W3 of the through-hole 50a is smaller than the width WT of the connection terminal 50, and the length is smaller than the width W2 of the opening 90. The through-hole 50a communicates with the opening 90.

[0064] The proportion of the area of all the connection terminals 50 (including the through-hole portion) with respect to the area of the opening 90 is set to be 40% or more, for example, 43%.

[0065] In the present embodiment, the 13 connection terminals 50 are arranged in the following order taking into account the influence of crosstalk. As shown in Figure 7As shown, in one example, starting from the extension end side of the connection end 48c, the four connection terminals 50(R) for the read head, the two connection terminals 50(S) for the HDI sensor, the two connection terminals 50(A) for the auxiliary element (high-frequency auxiliary element or thermal auxiliary element), the two connection terminals 50(H) for the heater, the two connection terminals 50(W) for the write head, and finally the one connection terminal 50(G) for the gimbal microactuator (GMA) (piezoelectric element 53). That is, the connection terminals 50(A) for the auxiliary element are arranged in the center of the arrangement direction (the 6th and 7th from the base end side), the connection terminals 50(W) for the write head are arranged on the base end side of the connection end 48c, and the connection terminal 50(H) for the heater is provided between the connection terminals 50(A) for the auxiliary element and the connection terminals 50(W) for the write head. The connection terminal 50(R) for the read head is disposed on the front end side of the connection end 48c, and the connection terminal 50(S) for the HDI sensor is provided between the connection terminal 50(A) for the auxiliary element and the connection terminal 50(R) for the read head.

[0066] Based on the above arrangement, the spacing between the connection terminal 50(W) for the write head and the connection terminal 50(A) for the auxiliary element, and the spacing between the connection terminal 50(R) for the read head and the connection terminal 50(A) for the auxiliary element, can be widened, thus preventing crosstalk between terminals during operation. Furthermore, by placing the connection terminal 50(W) for the write head at the base of the connection end 48c, the length of the wiring between the connection terminal 50(W) and the magnetic head 17 can be minimized, reducing wiring impedance. Moreover, the arrangement of the connection terminals 50 is not limited to the above arrangement; to avoid crosstalk, it is acceptable to arrange the connection terminals for the write head and the connection terminals for the read head so that they are not adjacent to the connection terminals for the auxiliary element.

[0067] like Figure 7 and Figure 8 As shown, the substrate insulating layer 86a covering the connection terminal 50 and the wiring S has a plurality of first openings OP1 and a plurality of second openings OP2 arranged in the length direction of the connection end 48c. The plurality of first openings OP1 are respectively provided at positions opposite to the connection terminal 50. The plurality of second openings OP2 are respectively provided at positions opposite to the space between the connection terminals 50.

[0068] like Figure 8As shown, the first opening OP1 faces the through hole 50a of the connecting terminal 50. The width W4 of the first opening OP1 is larger than the width W3 of the through hole 50a, but smaller than the width WT of the connecting terminal 50. In the length direction of the opening 90, the side edge of the first opening OP1 is located between the side edge (periphery) of the through hole 50a and the side edge of the connecting terminal 50. In the width direction of the opening 90, the length of the first opening OP1 is longer than the length of the through hole 50a, but shorter than the length of the connecting terminal 50 (the width W2 of the opening 90). The region (both ends) of the first opening OP1 located outside the through hole 50a in the length direction gradually narrows in width towards the root side of the connecting terminal 50.

[0069] Multiple second openings OP2 are respectively oriented towards the space between two adjacent connecting terminals 50 and one end and the other end of the opening 90 along its length direction relative to the space between the connecting terminals 50. Each second opening OP2 has a generally rectangular shape corresponding to the shape of the space. The width W5 of the second opening OP2 is smaller than the width WS of the space, and the length of the second opening OP2 is smaller than the width W2 of the opening 90. As a result, the periphery of the second opening OP2 is slightly separated from the side edge of the connecting terminal 50 and the side edge of the opening 90. In the length direction of the opening 90, the side edge of each connecting terminal 50 is located between the side edge of the first opening OP1 and the side edge of the second opening OP2.

[0070] Figure 9 It is along Figure 8 A cross-sectional view of the connecting end of line AA. Figure 10 It is along Figure 8 A cross-sectional view of the connecting end of line BB.

[0071] As shown in the figure, the two side edges of each connecting terminal 50 are covered by the substrate insulating layer 86a. Additionally, the two ends along the length of each connecting terminal 50, i.e., the root portions on both sides, are covered by the substrate insulating layer 86a. The through-hole 50a of the connecting terminal 50 opens at the first opening OP1 and the opening 90. The second opening OP2 of the substrate insulating layer 86a opens at the opening 90 of the cover insulating layer 86c.

[0072] According to the above structure, the periphery of each connecting terminal 50 is covered by and supported by the substrate insulating layer 86a. Therefore, even if the thickness of the conductive layer (copper foil) on which the connecting terminal 50 is formed is reduced, the rigidity of the connecting terminal 50 can be maintained.

[0073] Figure 11 (a) is a cross-sectional view showing the state in which the connecting end 48c of the flexible member is arranged to overlap with the connecting pad group 72 of the joint 64. Figure 11 (b) is a cross-sectional view of the joint ends and joint after soldering.

[0074] In the case of soldering the connecting end portion 48c of the flexible member 48 configured as described above to the bonding portion 64 of the FPC unit, as shown in Figure 11 (a), the connecting end portion 48c is arranged so as to overlap the connecting pad group 72 of the bonding portion 64. The connecting end portion 48c is arranged so as to face the bonding portion 64 with the cover insulating layer 68c. The 13 connecting terminals 50 are arranged so as to overlap the corresponding connecting pads 73 and the solder layer 78 of the bonding portion 64 via the openings 90.

[0075] In this state, laser light is irradiated toward the connecting end portion 48c and the bonding portion 64 from the connecting end portion 48c side. The laser light is irradiated toward the connecting terminals 50 and the solder layer 78 through the first opening OP1 of the connecting end portion 48c. The connecting terminals 50 and the solder layer 78 directly absorb heat, so that the solder layer 78 is melted, and the connecting terminals 50 and the connecting pads 73 are soldered. At the same time, the laser light is irradiated toward the bonding portion (FPC) 64 through the second opening OP2 of the connecting end portion 48c and the openings 90, and the bonding portion 64 is heated. The heat of the bonding portion 64 is transmitted to the solder layer 78 via the connecting pads 73, and contributes to the melting of the solder layer 78.

[0076] As shown in Figure 11 (b), the melted solder layer 78 spreads on the surface on the side of the cover insulating layer 68c of the connecting terminals 50, and flows into the first opening OP1 through the through holes 50a of the connecting terminals 50, and also joins the surface on the opposite side of the connecting terminals 50. Thus, the connecting terminals 50 and the connecting pads 73 are electrically and mechanically joined by the solder layer 78, and the electrical conductivity therebetween is ensured.

[0077] As shown in Figure 1 In the state where the actuator assembly 22 and the FPC unit 21 configured as described above are incorporated into the base 12, the actuator assembly 22 is supported so as to be rotatable about the support shaft 26. Each of the magnetic disks 18 is positioned between the two suspension assemblies 30. When the HDD is in operation, the magnetic head 17 mounted to the suspension assembly 30 faces the upper and lower surfaces of the magnetic disk 18, respectively. The base portion 60 of the FPC unit 21 is fixed to the bottom wall 12a of the base 12.

[0078] According to the HDD and the suspension assembly configured as above, in the connection end portion 48c of the flexure 48, the peripheral portion of each connection terminal 50 is supported by being covered with the base insulating layer 68a. Thus, even in the case where the film thickness of the conductive layer (copper foil) in which the connection terminal 50 is formed is thinned, the strength and rigidity of the connection terminal 50 can be maintained, and bending of the connection terminal and the like in the manufacturing process can be prevented. Further, by thinning the film thickness of the conductive layer, it will be possible to make the pitch of the wiring S formed of the conductive layer narrower. By the reduction in the pitch of the wiring, it is possible to reduce the width Wl of the connection end portion 48c, and to achieve miniaturization of the flexure 48 and the connection end portion 48c. In addition, in the present embodiment, by narrowing the width of both end portions of the first opening OP1 in the connection end portion 48c, both portions of the connection terminal are covered with the base insulating layer 68a in a wide range. Thus, it is possible to efficiently improve the strength and rigidity of the connection terminal.

[0079] Further, in the connection end portion 48c, the base insulating layer 68a is provided so as to have a plurality of second openings OP2 each facing a space portion between the connection terminals. Thus, at the time of joining of the connection end portion 48c, it is possible to irradiate the joining portion 64 of the FPC with laser light through the second openings OP2, and to promote melting of the solder layer by the heat generation of the joining portion 64. Thus, it is possible to eliminate insufficient melting and non-bonding of the solder, and to improve the reliability of the joining of the connection terminal.

[0080] As described above, according to the present embodiment, it is possible to obtain a suspension assembly capable of maintaining the strength of the connection terminal and achieving narrow-pitching of the wiring and improvement in the joining of the connection terminal, and a disc device provided with the same.

[0081] Next, the HDD and the suspension assembly of other embodiments will be described. In the other embodiments described below, the same reference numerals are assigned to the same portions as those of the first embodiment described above, and detailed description thereof will be omitted or simplified, and the description will be made focusing on the portions different from the first embodiment.

[0082] (Second Embodiment)

[0083] Figure 12 (a) is a plan view showing a portion of the joining portion 64 of the FPC in the HDD of the second embodiment, Figure 12 (b) is a sectional view showing a state where the connection end portion 48c of the flexure and the connection pad group 72 of the joining portion 64 are arranged so as to overlap each other.

[0084] As shown in the figure, according to the second embodiment, each of the connection pads 73 of the joint portion 64 integrally has an extension portion 73a extending to a position opposite the second opening OP2 of the connection end portion 48c. A resin layer (insulating layer) 88 of polyimide or the like is provided so as to overlap the extension portion 73a and the joint portion 64. The resin layer 88 is opposite the second opening OP2.

[0085] As shown in (b), in the case where laser irradiation is performed at the time of joining, the laser is irradiated through the first opening OP1 of the connection end portion 48c toward the connection terminal 50 and the solder layer 78. The solder layer 78 is melted by the connection terminal 50 and the solder layer 78 directly absorbing heat, and the connection terminal 50 and the connection pad 73 are solder-joined. At the same time, the laser is irradiated through the second opening OP2 of the connection end portion 48c and the opening 90 toward the resin layer 88 of the joint portion (FPC) 64, and heat is absorbed by the resin layer 88. The heat of the resin layer 88 is transmitted to the solder layer 78 via the connection pad 73, and contributes to the melting of the solder layer 78. Thus, the solderability can be further improved. Figure 12 In the second embodiment, the other structures of the connection end portion 48c and the joint portion 64 are common to those of the connection end portion and the joint portion in the aforementioned first embodiment. In the second embodiment, the same effects as those of the aforementioned first embodiment can be obtained.

[0086] (Third Embodiment)

[0087]

[0088] Figure 13 is an enlarged plan view of a part of the connection end portion of the flexible member in the HDD of the third embodiment.

[0089] As shown in the figure, according to the third embodiment, both side edges of the connection terminal 50 and both side edges of the through-hole 50a are not straight lines, and each has a convex portion 50b, 51a of a circular arc shape protruding toward the second opening OP2 side. The convex portion 50b is located at substantially the center of the length direction of the side edge of the through-hole 50a, and extends beyond the side edge of the first opening OP1 toward the second opening OP2 side. Similarly, the convex portion 51a is located at substantially the center of the length direction of the side edge of the connection terminal 50, and is opposite the convex portion 50b in the width direction. The convex portions 50b and 51a are covered by the base insulating layer 68a.

[0090] As described above, by providing the convex portions 50b, 51a in the side edge of the through-hole 50a and the side edge of the connection terminal 50, respectively, it is possible to maintain the rigidity of the connection terminal 50, and increase the area of the through-hole 50a and the contact area of the connection terminal 50 with the solder. Thus, it is possible to improve the joining strength of the solder with respect to the connection terminal 50.

[0091] ​In the third embodiment, the other structure of the connection end portion 48c is common to that of the connection end portion in the first embodiment described above. In the third embodiment, the same operational effects as those of the first embodiment described above can be obtained.

[0092] (4th Embodiment)

[0093] Figure 14 Fig. 9 is a plan view of the connection end portion of the flexure in the HDD of the fourth embodiment.

[0094] According to the fourth embodiment, the connection end portion 48c is provided with a structure having 14 connection terminals 50. As shown in the figure, the cover insulating layer has, for example, openings 90 each having a length L2 of about 6 mm and a width W2 of 0.5 mm. The 14 connection terminals 50 are arranged in opposition to the openings 90, and are arranged at intervals in the length direction of the openings 90.

[0095] The width WT of each connection terminal 50 is set to 0.2 mm as in the first embodiment. In the present embodiment, one connection terminal 50 (G) for a micro-actuator (piezoelectric element) is added. This connection terminal 50 (G) is arranged at the end of the opening 90 on the proximal end side. The arrangement of the other 13 connection terminals 50 is set as in the first embodiment.

[0096] In one example, the connection terminals 50 are arranged in the order of four connection terminals 50 (R) for a read head, two connection terminals 50 (S) for an HDI sensor, two connection terminals 50 (A) for an auxiliary element (high-frequency auxiliary element or thermal auxiliary element), two connection terminals 50 (H) for a heater, two connection terminals 50 (W) for a write head, and finally two connection terminals 50 (G) for a gimbal micro-actuator (GMA) (piezoelectric element 53) from the distal end side of the connection end portion 48c. The connection terminals 50 (A) for the auxiliary element are arranged in the central portion in the arrangement direction (the sixth and seventh from the proximal end side), the connection terminals 50 (W) for the write head are arranged on the proximal end side of the connection end portion 48c, and the connection terminals 50 (H) for the heater are provided between the connection terminals 50 (A) for the auxiliary element and the connection terminals 50 (W) for the write head. The connection terminals 50 (R) for the read head are arranged on the distal end side of the connection end portion 48c, and the connection terminals 50 (S) for the HDI sensor are provided between the connection terminals 50 (A) for the auxiliary element and the connection terminals 50 (R) for the read head.

[0097] The base insulating layer 86a covering the connection terminals 50 and the wiring S has a plurality of first openings OP1 and a plurality of second openings OP2 arranged in the length direction of the connection end portion 48c. The plurality of first openings OP1 are respectively provided at positions facing the 14 connection terminals 50. The plurality of second openings OP2 are respectively provided at positions facing the space portions between the connection terminals 50 and the space portions between the connection terminals and the one end and the other end of the length direction of the opening 90.

[0098] In the fourth embodiment, the other structure of the connection end portion 48c is the same as that of the connection end portion 48c in the first embodiment. In the fourth embodiment having 14 connection terminals, the same effects as those of the aforementioned first embodiment can be obtained.

[0099] The present application is not limited to the above-described embodiments, and in the implementation stage, the constituent elements can be modified and embodied within the scope of the gist thereof. In addition, various applications can be formed by appropriate combinations of the plurality of constituent elements disclosed in the above-described embodiments. For example, some of the constituent elements shown in the embodiments can be deleted. Furthermore, the constituent elements in different embodiments can be appropriately combined.

[0100] The number of disks is not limited to five, and can be set to four or less or six or more. The number of suspension assemblies and the number of heads can be increased or decreased according to the number of disks. In the connection end portion of the suspension assembly, the shape and size of the connection terminal, and the shape and size of the first opening and the second opening are not limited to those of the above-described embodiments, and various modifications can be made as needed. The type and function of the connection terminal are not limited to those of the above-described embodiments, and various modifications can be made according to the function of the head and the suspension assembly.

Claims

1. A suspension assembly comprising: Support plate; The head, supported on the support plate; and Wiring components are disposed on the support plate. The wiring component has a front end that is electrically connected to the head, a connecting end that extends outward from the support plate, and a plurality of wirings extending between the front end and the connecting end. The connection end comprises: a cover layer having an opening of a predetermined length; 13 or more connection terminals facing the opening and arranged with gaps in the length direction of the opening, respectively connected to the wiring; and a base layer overlapping the cover layer and the connection terminals, having a plurality of first openings facing a portion of the connection terminals and a plurality of second openings facing the space between adjacent connection terminals.

2. The suspension assembly according to claim 1, The connecting terminal has a through hole that opens at the opening in the cover layer and at the first opening.

3. The suspension assembly according to claim 2, The connecting terminal has a pair of opposing side edges spaced apart along the length of the opening. The through hole has a periphery located between the pair of side edges. The first opening is an opening larger than the through hole, and has a pair of side edges located between the side edge of the connecting terminal and the periphery of the through hole.

4. The suspension assembly according to claim 3, The second opening has a periphery that is spaced apart from the side edge of the connecting terminal and the side edge of the opening of the cover layer.

5. The suspension assembly according to claim 3, The first opening has two ends that are respectively opposite to the root portion of the connecting terminal. The width of each end portion narrows as it faces the root of the connecting terminal.

6. The suspension assembly according to claim 3, The side edge of the connecting terminal and the periphery of the through hole each have a protrusion that protrudes toward the second opening side.

7. The suspension assembly according to claim 6, The protrusion at the periphery of the through hole protrudes toward the second opening beyond the side edge of the first opening.

8. The suspension assembly according to claim 1, The 13 or more connection terminals include multiple connection terminals for the write head, multiple connection terminals for the read head, multiple connection terminals for auxiliary components, multiple connection terminals for the heater, connection terminals for the HDI sensor, and connection terminals for the micro actuator. A connection terminal for the HDI sensor or a connection terminal for the heater is disposed between the connection terminal for the auxiliary component and the connection terminal for the read head. A connection terminal for the HDI sensor or a connection terminal for the heater is disposed between the connection terminal for the auxiliary element and the connection terminal for the write head.

9. A disk device comprising: A disc-shaped recording medium having a recording layer; and The head actuator comprises a rotatable actuator block, multiple arms extending from the actuator block, a circuit board having multiple connected pads arranged in a plurality of overlapping surfaces with the actuator block, solder respectively disposed on the connected pads, and a suspension assembly as described in claim 1 respectively fixed to the arms. The connecting end of the wiring component is disposed on the circuit board overlapping the connecting pad and the solder, and the plurality of connecting terminals are joined to the connecting pad by the solder.

10. The disk device according to claim 9, Each connection pad of the circuit board has an extension facing the second opening at the connection end. The circuit board has a resin layer that overlaps with the extension portion and faces the second opening.

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