JP6019201B2 - Suspension for disk unit - Google Patents

Description

The present invention, for example, relate to Suspension disk unit having an actuator element made of PZT or the like.

  A hard disk drive (HDD) is used for an information processing apparatus such as a personal computer. The hard disk device includes a magnetic disk that rotates about a spindle, a carriage that rotates about a pivot shaft, and the like. The carriage has an actuator arm, and is rotated in the track width direction of the disk about a pivot axis by a positioning motor such as a voice coil motor.

  A suspension is attached to the actuator arm. The suspension includes a load beam, a flexure disposed on the load beam, and the like. A slider constituting the magnetic head is attached to a gimbal portion formed near the tip of the flexure. The slider is provided with an element (transducer) for accessing data such as reading or writing.

  In order to cope with the higher recording density of the disk, it is necessary to be able to position the magnetic head with higher accuracy with respect to the recording surface of the disk. Therefore, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-307442 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2002-50140 (Patent Document 2), a positioning motor (voice coil motor) and PZT (zircon titanium) are disclosed. DSA suspensions that are used in combination with actuator elements made of piezoelectric materials such as lead oxide have been developed. DSA is an abbreviation for Dual Stage Actuator.

  By applying a voltage to the actuator element and deforming the actuator element, the tip end side of the suspension can be moved at a high speed in the sway direction (track width direction). This actuator element is disposed on an actuator mounting portion provided in a part of the suspension.

  An opening is formed in the plate member that forms part of the actuator mounting portion, and the actuator element is accommodated in the opening. For example, as disclosed in Japanese Patent Application Laid-Open No. 2002-184140 (Patent Document 3), a plate member having an opening has a fixed portion and a movable portion. One end of the actuator element is fixed to the fixed portion of the plate member with an adhesive. The other end of the actuator element is fixed to the movable part of the plate member with an adhesive.

JP 2001-307442 A JP 2002-50140 A JP 2002-184140 A

  An example of the plate member includes a first plate and a second plate. The first plate and the second plate are fixed by laser welding in a state where they are stacked in the thickness direction. The adhesive is supplied to the inner surface of the opening of the plate member in an uncured state. After the actuator element is disposed in the opening, the adhesive is cured. However, in the case of the plate member composed of the first plate and the second plate, the adhesive may enter the mating surface of the first plate and the second plate due to capillary action. The adhesive that has entered between the first plate and the second plate may affect the rigidity of the actuator mounting portion, which may adversely affect the characteristics of the actuator mounting portion.

Accordingly, the object of this invention is in the suspension having an actuator element such as PZT, that the adhesive for fixing the actuator device to provide a Suspension disk unit capable of suppressing the influence the stiffness of the actuator mounting portion .

The disk device suspension according to the present invention includes a plate member including a first plate and a second plate. The first plate has an opening for accommodating an actuator element, and has a fixed portion to which one end of the actuator element is fixed, a movable portion to which the other end of the actuator element is fixed , the fixed portion, and the movable It has the bridge part which connects the part . The second plate includes a main body portion that overlaps the first plate in a thickness direction, a support portion that supports the one end and the other end of the actuator element, a bridge portion that overlaps the bridge portion, and the bridge portion. width is respectively of one end and the other end than the said bridge portion has a narrow narrow portion. The narrow portion is provided with a welding sealing portion formed by welding the first plate and the second plate. An adhesive is provided between the one end and the other end of the actuator element and the inner surface of the opening.

  In one embodiment of the present invention, the narrow portion is formed in a region narrower than the width of the support portion in the vicinity of the support portion. In this embodiment, a plurality of the narrow portions may be formed at intervals in the width direction of the support portion, and the welded sealing portion may be provided in each of the narrow portions.

  In another embodiment, the first plate has a bridge portion that connects the fixed portion and the movable portion, and the narrow portion is a bridge portion that overlaps the bridge portion of the main body portion of the second plate. Is formed. Moreover, you may further provide the welding part for couple | bonding the said 1st plate and the 2nd plate mutually. In this embodiment, both the welded portion and the welded seal portion may be laser spot welded portions.

  According to the present invention, it is possible to suppress the adhesive that fixes the actuator element from entering between the first plate and the second plate, thereby suppressing the rigidity of the actuator mounting portion from being affected by the adhesive. it can.

The perspective view which shows an example of a disc apparatus. FIG. 2 is a cross-sectional view of a part of the disk device shown in FIG. 1. 1 is a perspective view of a suspension according to a first embodiment. FIG. 4 is a plan view of an actuator mounting portion of the suspension shown in FIG. 3. Sectional drawing of the actuator mounting part which follows the F5-F5 line | wire in FIG. The top view of a part of 1st plate of the actuator mounting part shown by FIG. The top view of a part of 2nd plate of the actuator mounting part shown by FIG. The top view of the actuator mounting part of the suspension which concerns on 2nd Embodiment. The top view of a part of 2nd plate of the actuator mounting part shown by FIG. The top view of the actuator mounting part of the suspension which concerns on 3rd Embodiment. The top view of a part of 2nd plate of the actuator mounting part shown by FIG. The top view of the actuator mounting part of the suspension which concerns on 4th Embodiment. The top view of the actuator mounting part of the suspension which concerns on 5th Embodiment. The perspective view of the suspension which concerns on 6th Embodiment. The top view of the actuator mounting part of the suspension shown by FIG.

A disk device suspension according to a first embodiment of the present invention will be described below with reference to FIGS.
A disk device (HDD) 1 shown in FIG. 1 includes a case 2, a disk 4 that rotates about a spindle 3, a carriage 6 that can pivot about a pivot shaft 5, and a positioning motor that drives the carriage 6. (Voice coil motor) 7 and the like. Case 2 is sealed with a lid (not shown).

  FIG. 2 is a cross-sectional view schematically showing a part of the disk device 1. As shown in FIGS. 1 and 2, the carriage 6 is provided with an arm (carriage arm) 8. A suspension 10 is attached to the tip of the arm 8. A slider 11 constituting a magnetic head is provided at the tip of the suspension 10. When the disk 4 rotates at a high speed, an air bearing is formed between the disk 4 and the slider 11.

  When the carriage 6 is turned by the positioning motor 7, the suspension 10 moves in the radial direction of the disk 4, so that the slider 11 moves to a desired track of the disk 4. At the end of the slider 11, an element capable of converting a magnetic signal and an electric signal, such as an MR element, is provided. By this element, data writing or reading access to the disk 4 is performed.

  FIG. 3 shows a DSA type suspension 10. DSA is an abbreviation for Dual Stage Actuator. The suspension 10 includes a base portion 20 fixed to the arm 8 (shown in FIGS. 1 and 2) of the carriage 6, an actuator mounting portion 21, a load beam 22, a flexure with conductors 23, and the like. ing. The base portion 20 is formed with a boss portion 20a to be inserted into a hole 8a (shown in FIG. 2) formed in the arm 8.

  The direction indicated by the arrow X in FIG. 3 is the longitudinal direction of the load beam 22, that is, the longitudinal direction (front-rear direction) of the suspension 10. Arrow S is the sway direction. At the base portion (rear end portion) of the load beam 22, a hinge portion 25 that can be elastically bent in the thickness direction is formed. The actuator mounting portion 21 is provided between the base portion 20 and the load beam 22 and has a function of moving the load beam 22 in the sway direction (direction indicated by the arrow S).

  The flexure 23 is disposed along the load beam 22 and is fixed to the load beam 22 by fixing means such as laser spot welding. A tongue 23a (shown in FIG. 3) that functions as a gimbal portion is formed in the vicinity of the distal end portion of the load beam 22, that is, in the vicinity of the distal end portion of the flexure 23. A slider 11 that forms a magnetic head is attached to the tongue 23a. The load beam 22, the flexure 23, the slider 11 and the like constitute a head gimbals assembly. The rear portion 23 b of the flexure 23 extends to the rear of the base portion 20.

  FIG. 4 shows the actuator mounting portion 21. FIG. 5 is a cross-sectional view of the actuator mounting portion 21 taken along line F5-F5 in FIG. The actuator mounting portion 21 includes a plate member 30 composed of a first plate 31 and a second plate 32, and a pair of actuator elements 41, 42 composed of a plate-like piezoelectric material such as PZT.

  As shown in FIG. 5, the plate member 30 is configured by stacking a first plate 31 and a second plate 32 in the thickness direction. The thickness of the first plate 31 is larger than the thickness of the second plate 32. The first plate 31 and the second plate 32 are each made of austenitic stainless steel such as SUS304. The chemical components of SUS304 are: C: 0.08 or less, Si: 1.00 or less, Mn: 2.00 or less, Ni: 8.00 to 10.50, Cr: 18.00 to 20.00, the balance being Fe It is.

  The first plate 31 and the second plate 32 are fixed to each other by a laser welded portion W1 (partly shown in FIGS. 3 and 4). This weld W1 is formed by condensing laser light by a laser welding apparatus (not shown). A part (front portion) of the plate member 30 constituted by these two plates 31 and 32 constitutes the actuator mounting portion 21. The remaining part (rear part) of the plate member 30 constitutes the base part 20.

  FIG. 6 shows a part of the first plate 31. The first plate 31 has openings 51 and 52 that can accommodate the actuator elements 41 and 42. The actuator elements 41 and 42 are accommodated in the openings 51 and 52. The first plate 31 has a fixed portion 31a connected to the base portion 20, a movable portion 31b fixed to the hinge portion 25 of the load beam 22, and a bridge portion 31c that connects the fixed portion 31a and the movable portion 31b. doing. The fixed portion 31 a is a portion that does not substantially move with respect to the base portion 20. The movable portion 31 b is a portion that is moved in the sway direction by the actuator elements 41 and 42. A bridge portion 31 c that connects the fixed portion 31 a and the movable portion 31 b extends in the longitudinal direction of the suspension 10.

  FIG. 7 shows a part of the second plate 32. The second plate 32 includes a main body portion 60 that overlaps the first plate 31, a pair of support portions 61 and 62 that support both ends 41 a and 41 b of one actuator element 41, and both ends 42 a and 42 b of the other actuator element 42. It has a pair of support parts 63 and 64 to support, and a bridge part 65. The bridge portion 65 is formed at a position corresponding to the bridge portion 31 c of the first plate 31.

  As shown in FIGS. 4 and 7, narrow portions 71, 72, 73, 74 that are narrower than the first plate 31 are formed in the main body portion 60 of the second plate 32. That is, narrow portions 71 and 72 are formed in the vicinity of the support portions 61 and 62 that support one actuator element 41, respectively. Also, narrow portions 73 and 74 are formed in the vicinity of the support portions 63 and 64 that support the other actuator element 42, respectively. The width L1 (shown in FIG. 7) of each of the narrow portions 71, 72, 73, 74 is smaller than the width L2 of the support portions 61, 62, 63, 64. These narrow portions 71, 72, 73, 74 are in the vicinity of the support portions 61, 62, 63, 64 in a region narrower than the width L2 of the support portions 61, 62, 63, 64, as shown in FIG. Is formed.

  As shown in FIG. 4, a welded sealing portion 80 is formed on all of the narrow portions 71, 72, 73, 74. In FIG. 4, the welded sealing portion 80 is indicated by hatching for convenience of explanation. The welding sealing portion 80 is formed over both the first plate 31 and the second plate 32 by melting the first plate 31 and the second plate 32 by laser spot welding, which is an example of laser welding. These welded sealing portions 80 seal the mating surface G (schematically shown in FIG. 5) between the first plate 31 and the second plate 32 in the narrow portions 71, 72, 73, 74. .

  As shown in FIG. 4, the actuator elements 41 and 42 are rectangular in a plan view. An adhesive 85 is provided between one end 41 a of one actuator element 41 and the inner surface 51 a of the opening 51. An adhesive 85 is also provided between the other end 41 b of the actuator element 41 and the inner surface 51 b of the opening 51. An adhesive 85 is provided between one end 42 a of the other actuator element 42 and the inner surface 52 a of the opening 52. An adhesive 85 is also provided between the other end 42 b of the actuator element 42 and the inner surface 52 b of the opening 52. The adhesive 85 is made of, for example, a thermosetting polymer material having electrical insulation, and is supplied to the inner surfaces 51a, 51b, 52a, 52b of the openings 51, 52 and the support portions 61, 62, 63, 64 in a liquid state. Is done. After that, the actuator elements 41 and 42 are arranged in the openings 51 and 52. And the adhesive agent 85 hardens | cures by heating. The adhesive 85 may be a photo-curing adhesive. The photocurable adhesive can be cured by, for example, irradiating with ultraviolet rays.

  As representatively showing one actuator element 41 in FIG. 5, the first electrode 90 is provided on one surface in the thickness direction of the actuator element 41. The first electrode 90 is electrically connected to the first plate 31 via a first conductive member 91 such as a silver paste. A second electrode 92 is provided on the other surface of the actuator element 41. The second electrode 92 is connected to a wiring portion (not shown) of the flexure 23 via a second conductive member 93 such as a bonding wire. The other actuator element 42 is configured in the same manner as the actuator element 41.

The manufacturing method of the suspension 10 includes the following steps.
(1) The first plate 31 having the openings 51 and 52 that can accommodate the actuator elements 41 and 42 is formed by pressing or etching a metal plate made of stainless steel or the like.
(2) The second plate 32 having the main body portion 60, the support portions 61, 62, 63, 64 and the narrow portions 71, 72, 73, 74 by pressing or etching a metal plate made of stainless steel or the like. Form.
(3) The first plate 31 and the second plate 32 are overlapped.
(4) In the narrow portions 71, 72, 73, 74, the first plate 31 and the second plate 32 are welded to each other by laser welding, so that the welded sealing portion 80 is attached to the narrow portions 71, 72, 73, 74. Form.
(5) Uncured adhesive 85 is supplied to the inner surfaces 51a, 52a of the openings 51, 52 and the support portions 61, 62, 63, 64.
(6) The actuator elements 41 and 42 are disposed in the openings 51 and 52, respectively.
(7) The welding sealing portion 80 of the narrow portions 71, 72, 73, 74 that the uncured adhesive 85 moves toward the back of the mating surface of the first plate 31 and the second plate 32. Stop by.
(8) The adhesive 85 is cured.

The operation of the suspension 10 will be described below.
When the carriage 6 (shown in FIGS. 1 and 2) is turned by the positioning motor 7, the suspension 10 moves in the radial direction of the disk 4 so that the slider 11 of the magnetic head moves to a desired track on the recording surface of the disk 4. To do. When a voltage is applied to the actuator elements 41 and 42, the actuator elements 41 and 42 are distorted in opposite directions according to the voltage, thereby causing the load beam 22 to be minute in the sway direction (the direction indicated by arrow S in FIG. Can be moved. For example, when one actuator element 41 extends and the other actuator element 42 contracts, the load beam 22 moves in the sway direction. For this reason, the slider 11 can be positioned in the sway direction at high speed and with high accuracy.

  As described above, in this embodiment, in the narrow portions 71, 72, 73, 74, the mating surface G (shown in FIG. 4) between the first plate 31 and the second plate 32 is formed by the welded sealing portion 80. It is sealed. For this reason, the uncured adhesive 85 supplied to the support portions 61, 62, 63, 64 in the liquid state passes through the narrow portions 71, 72, 73, 74 and is between the first plate 31 and the second plate 32. It is possible to prevent the welding sealing portion 80 from penetrating into the back of the mating surface G by capillary action. For this reason, it can suppress that the adhesive agent 85 enters between the 1st plate 31 and the 2nd plate 32, and can suppress that the rigidity of the actuator mounting part 21 is influenced by the adhesive agent 85. It is.

  Moreover, the welding sealing part 80 can be formed with the laser welding machine used for the laser spot welding part W1 for fixing the 1st plate 31 and the 2nd plate 32. FIG. For this reason, the laser welding machine for the laser spot welded portion W1 can be used as it is for the welded sealed portion 80 without adding any special equipment for melting the welded sealed portion 80. The welding sealing part 80 can also serve as a function of fixing the first plate 31 and the second plate 32 to each other.

  8 and 9 show a second embodiment. The width L3 (shown in FIG. 9) of the narrow portions 71, 72, 73, 74 of the actuator mounting portion 21A of this embodiment is the width L1 of the narrow portions 71, 72, 73, 74 of the first embodiment ( Larger than that shown in FIG. As shown in FIG. 8, the narrow portions 71, 72, 73 and 74 are each provided with a plurality of welded sealing portions 80 by laser spot welding. Since other configurations and effects are the same as those of the actuator mounting portion 21 of the first embodiment, common portions are denoted by common reference numerals, and description thereof is omitted.

  10 and 11 show a third embodiment. In the second plate 32 of the actuator mounting portion 21B of this embodiment, a plurality of narrow portions 71, 72, 73, 74 are provided for the support portions 61, 62, 63, 64, respectively. Are formed at intervals in the width direction. As shown in FIG. 11, the narrow portions 71, 72, 73, 74 are formed in regions narrower than the width L <b> 2 of the support portions 61, 62, 63, 64. A welded sealing portion 80 is provided in all of the narrow portions 71, 72, 73, 74. Since other configurations and effects are the same as those of the actuator mounting portion 21 of the first embodiment, common portions are denoted by common reference numerals, and description thereof is omitted.

  FIG. 12 shows an actuator mounting portion 21C according to the fourth embodiment. In this embodiment, narrow portions 71 and 72 are provided at both ends of the bridge portion 65 of the second plate 32. A welded and sealed portion 80 is formed in the narrow portions 71 and 72. In this welding sealing portion 80, the uncured adhesive 85 supplied to the support portions 61, 62, 63, 64 is provided between the bridge portion 31 c of the first plate 31 and the bridge portion 65 of the second plate 32. Suppresses entering and solidifying the mating surfaces. Since other configurations and effects are the same as those of the actuator mounting portion 21 of the first embodiment, common portions are denoted by common reference numerals, and description thereof is omitted.

  FIG. 13 shows an actuator mounting portion 21D according to the fifth embodiment. In this embodiment, narrow portions 71 and 72 having a width larger than the narrow portions 71 and 72 of the fourth embodiment (FIG. 12) are formed at both ends of the bridge portion 65. Each of the narrow portions 71 and 72 is provided with a plurality of welding sealing portions 80 by laser spot welding. Other configurations and effects are the same as those of the actuator mounting portion 21C of the fourth embodiment.

  14 and 15 show a sixth embodiment. The actuator mounting portion 21E of this embodiment includes one actuator element 41. In addition, arm portions 100 curved in a U shape are formed on both sides of the plate member 30. A slit 101 is formed inside the arm portion 100. The plate member 30 includes a first plate 31 and a second plate 32 as in the actuator mounting portion 21 (shown in FIG. 4) of the first embodiment. The second plate 32 includes a main body portion 60 that overlaps the first plate 31 and support portions 61 and 62 that support both ends 41 a and 41 b of the actuator element 41. The main body 60 includes a plurality of narrow portions 71 and 72 and a welded sealing portion 80 in the vicinity of the support portions 61 and 62 and in a region narrower than the width L2 of the support portions 61 and 62. Are formed at intervals in the width direction of the support portions 61 and 62.

  In the actuator mounting portion 21E of this embodiment, when a voltage is applied to the actuator element 41 and deformed, one of the pair of arm portions 100 contracts and the other extends, thereby causing the load beam 22 to move in the sway direction (see FIG. 14). (Indicated by arrow S). Other configurations and effects are the same as those of the suspension 10 including the actuator mounting portion 21 of the first embodiment.

  In practicing the present invention, including the specific mode of the macro actuator mounting portion, the first plate and the second plate constituting the plate member, the narrow portion, the welding sealing portion, the adhesive, the actuator element, etc. It goes without saying that the specific aspects of the components of the suspension can be modified in various ways.

  DESCRIPTION OF SYMBOLS 1 ... Disk apparatus, 10 ... Suspension, 22 ... Load beam, 21, 21A, 21B, 21C, 21D, 21E ... Actuator mounting part, 31 ... 1st plate, 31a ... Fixed part, 31b ... Movable part, 31c ... Bridge part 32 ... second plate 41,42 ... actuator element 51,52 ... opening 60 ... main body part 61,62,63,64 ... support part 65 ... bridge part 71,72,73,74 ... width Narrow part, 80 ... weld sealing part, 85 ... adhesive.

Claims (2)

A suspension for a disk device having an actuator element,
Connecting said has an opening for accommodating the actuator element and movable portion and a chromatic vital the fixed portion and the other end is fixed the fixed portion and said actuator element to which one end of the actuator element is fixed to the moving part A first plate having a bridge portion ;
A body portion that overlaps in the thickness direction with respect to the first plate, and a support portion that supports the one end and the other end of the actuator element, a bridge portion overlapping with the bridge portions, the one end and the other end of the bridge portion A second plate, each formed and having a narrow portion narrower than the bridge portion ;
A welding sealing portion formed by welding the first plate and the second plate to each other in the narrow portion;
An adhesive provided between the one end and the other end of the actuator element and the inner surface of the opening;
A suspension for a disk device, comprising: The disk device suspension according to claim 1, further comprising a fixing portion that fixes the first plate and the second plate to each other.

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