Head drive device

Abstract

To provide a head driving device capable of stably holding a head member and functioning as an actuator for fine movement.SOLUTION: A head driving device 10A includes a head support unit 16 for supporting a head member 17, a first beam 21, a second beam 22, a first piezoelectric unit 51 including a pair of piezoelectric elements 51a and 51b, and a second piezoelectric unit 61 including a pair of piezoelectric elements 61a and 61b. When a voltage is applied to the piezoelectric elements 51a and 51b of the first piezoelectric unit 51, the piezoelectric elements 51a and 51b are deformed to move a tip 21b of the first beam 21. The piezoelectric elements 61a and 61b of the second piezoelectric unit 61 are also deformed when the voltage is applied, to move a tip 22b of the second beam 22 in a direction same as that of the tip 21b of the first beam 21.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to a head driving device for a data storage device using a tape as a recording medium.

Background Art

[0002] Data storage devices using a tape (magnetic tape) as a recording medium are known. An example of a data storage device has a case, a tape housed inside the case, a tape winding mechanism, a head assembly, etc., as described in Patent Document 1 or Patent Document 2. Data is magnetically recorded on the tape. The head assembly includes a magnetic head and a head driving device that relatively moves the magnetic head with respect to the tape. The magnetic head has an element for accessing data recorded on the tape, such as reading or writing data.

[0003] The head driving device of the data storage device of Patent Document 1 includes a head stack assembly and a voice coil motor for moving the head stack assembly. A head arm having a spring function is provided at the tip of the head stack assembly. Magnetic heads are mounted on the head arms respectively. The magnetic head is moved in the width direction of the tape by the voice coil motor.

[0004] The head driving device of the data storage device of Patent Document 2 includes a coarse movement actuator for moving the magnetic head with a relatively large stroke and a fine movement actuator for moving the magnetic head with a relatively small stroke in order to cope with high recording density of the tape. A stepping motor or a VCM (voice coil motor) is used for the coarse movement actuator. Also, a piezoelectric body such as PZT (lead zirconate titanate) may be used as the fine movement actuator.

Prior Art Documents

Patent Document

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a conventional device where a small magnetic head moves in the width direction of a tape by a voice coil motor, like the head drive device of Patent Document 1, there is a concern that the tape may be damaged by contact with the magnetic head. Also, it is not easy for the conventional device to stably hold the magnetic head at a predetermined position with respect to the tape moving at high speed. In other conventional devices, it was also considered to use a large magnetic head having a length corresponding to the width of the tape, but such a large magnetic head has a large weight, so it is difficult to support it stably by a head arm having a suspension function.

[0007] A conventional device including a coarse movement actuator composed of a voice coil motor and a fine movement actuator composed of a piezoelectric element, like the head drive device of Patent Document 2, has problems such as a complicated structure and an increase in the number of parts. In the case of a hard disk drive using a disk as a recording medium, an air bearing is formed between the surface of the disk and the magnetic head. On the other hand, in the head drive device of Patent Document 2, a tape is used as the recording medium. The head drive device of Patent Document 2 prevents the tape from being damaged when the tape is fast-forwarded and rewound by preventing the tape from contacting the magnetic head. However, such a conventional device has an even more complicated structure of the head drive device.

[0008] An object of the present invention is to provide a head drive device that can stably hold a head member and can function as a fine movement actuator.

Means for Solving the Problem

[0009] A head driving device according to one embodiment includes a head support portion that supports a head member, a first beam, a first base-side hinge portion, a first head-side hinge portion, a second beam, a second base-side hinge portion, a second head-side hinge portion, a first piezoelectric unit, and a second piezoelectric unit.

[0010] The head driving device has a first base portion and a second base portion that face each other with a space therebetween. The head support portion is provided between the first base portion and the second base portion. The first beam extends from the first base portion toward the head support portion. The first base-side hinge portion connects the base of the first beam and the first base portion. The first head-side hinge portion connects the tip of the first beam and the head support portion.

[0011] The second beam is located on the side opposite to the first beam with the head support portion interposed therebetween, and extends from the second base portion toward the head support portion. The second base-side hinge portion connects the base of the second beam and the second base portion. The second head-side hinge portion connects the tip of the second beam and the head support portion. The first piezoelectric unit is disposed between the first base portion and the base of the first beam, and displaces the tip of the first beam by deforming when a voltage is applied. The second piezoelectric unit is disposed between the second base portion and the base of the second beam, and displaces the tip of the second beam by deforming when a voltage is applied.

[0012] In the above embodiment, the width of the first base-side hinge portion may be smaller than the width of the base portion of the first beam, and the width of the first head-side hinge portion may be smaller than the width of the tip of the first beam. Also, the width of the second base-side hinge portion may be smaller than the width of the base portion of the second beam, and the width of the second head-side hinge portion may be smaller than the width of the tip of the second beam.

[0013] In one embodiment of the head driving device, the planar shape of the first beam is a tapered shape in which the width decreases from the base portion of the first beam toward the tip of the first beam. The planar shape of the second beam is a tapered shape in which the width decreases from the base portion of the second beam toward the tip of the second beam.

[0014] In the head driving device, first element accommodating portions may be provided on both sides of the first base-side hinge portion, and a pair of first piezoelectric elements constituting the first piezoelectric unit may be arranged in these first element accommodating portions. Also, second element accommodating portions may be provided on both sides of the second base-side hinge portion, and a pair of second piezoelectric elements constituting the second piezoelectric unit may be arranged in these second element accommodating portions.

[0015] In one embodiment, one of the pair of first piezoelectric elements may be arranged in the first element accommodating portion with a predetermined polarity, and the other of the pair of first piezoelectric elements may be arranged in the first element accommodating portion with its orientation reversed so that the polarity is reversed. Also, one of the pair of second piezoelectric elements may be arranged in the second element accommodating portion with a predetermined polarity, and the other of the pair of second piezoelectric elements may be arranged in the second element accommodating portion with its orientation reversed so that the polarity is reversed.

[0016] As shown by way of example in FIG. 3, the head driving device according to one embodiment may include a first suspension and a second suspension made of a metal substrate. The first suspension includes the first beam, the first base-side hinge portion, and the first head-side hinge portion. The second suspension includes the second beam, the second base-side hinge portion, and the second head-side hinge portion. The second suspension is line-symmetric with the first suspension about an axis passing through the center of the head support portion as the axis of symmetry.

[0017] As shown in FIGS. 5 to 9, in the head driving device according to some embodiments, a damper member may be disposed on at least a part of the first beam, the second beam, and the head support portion.

[0018] For example, as shown in FIG. 10, the head driving device having the first suspension and the second suspension may include a first bending portion formed on the first suspension and a second bending portion formed on the second suspension. The first bending portion is bent with respect to the head support portion at an angle of 90° or less in the thickness direction of the substrate. The second bending portion is bent with respect to the head support portion at the same angle as the first bending portion on the same side as the first bending portion.

[0019] As shown in FIGS. 14 to 17, a first milli-actuator assembly and a second milli-actuator assembly may be provided. The first milli-actuator assembly includes a first head support portion, a first suspension, and a second suspension. The second milli-actuator assembly includes a second head support portion, a third suspension, and a fourth suspension. These first to fourth suspensions may be made of a common metal substrate and may have substantially the same configuration. The first suspension and the second suspension are line-symmetric with respect to each other with an axis passing through the center of the first head support portion as the axis of symmetry. The third suspension and the fourth suspension are line-symmetric with respect to each other with an axis passing through the center of the second head support portion as the axis of symmetry. The first head support portion and the second head support portion may be connected to each other by a connecting portion.

[0020] For example, like the three-dimensional head driving device shown in FIGS. 18 to 22, it may have a first bending portion, a second bending portion, a third bending portion, and a fourth bending portion. The first bending portion is formed on the first suspension and bends at an angle of 90° or less in the thickness direction of the substrate with respect to the first head support portion. The second bending portion is formed on the second suspension and bends on the same side as the first bending portion at the same angle as the first bending portion with respect to the first head support portion. The third bending portion is formed on the third suspension and bends on the same side as the first bending portion at the same angle as the first bending portion with respect to the second head support portion. The fourth bending portion is formed on the fourth suspension and bends on the same side as the first bending portion at the same angle as the first bending portion with respect to the second head support portion.

Effect of the Invention

[0021] According to the head driving device of the present invention, the head member can be stably held and can function as a fine movement actuator.

Brief Description of the Drawings

[0022]

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[0023] [First Embodiment] (FIGS. 1-4) Hereinafter, the head drive device 10A according to the first embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 is a plan view of the head drive device 10A. FIG. 2 is a cross-sectional view of the head drive device 10A taken along line F2-F2 in FIG. 1. The head drive device 10A has a flat substrate 11 made of metal (for example, stainless steel). FIG. 3 is a plan view of the substrate 11. The thickness of the substrate 11 is, for example, 0.1 - 0.3 mm (one example is 0.15 mm). One example of the length L1 of the substrate 11 is 20 mm, but other dimensions may also be used.

[0024] A frame portion 12 is formed on a part of the substrate 11. The frame portion 12 includes a first base portion 13 and a second base portion 14 that face each other with a space therebetween. The first base portion 13 and the second base portion 14 are connected to each other by a bridge portion 15. Therefore, the relative positions of the first base portion 13 and the second base portion 14 are substantially unchanged. An example of the distance L2 (shown in FIG. 3) between the first base portion 13 and the second base portion 14 is 15 mm, but other dimensions may also be used.

[0025] A head support portion 16 is provided at the center between the first base portion 13 and the second base portion 14. The head support portion 16 supports a head member 17 that functions as a magnetic head. The head member 17 may also be referred to as a head bar or a slider. The head member 17 is fixed to the head support portion 16 by fixing means such as an adhesive.

[0026] The head member 17 extends in the width direction T1 of a magnetic tape 18 (partially shown by a two-dot chain line in FIG. 1) as a recording medium. The head member 17 is provided with an element capable of converting a magnetic signal and an electrical signal, such as an MR element. Through these elements, access such as writing or reading data to / from the magnetic tape 18 is performed.

[0027] The head driving device 10A includes a first beam 21 and a second beam 22. The first beam 21 extends from the first base portion 13 toward the head support portion 16. The second beam 22 is provided on the side opposite to the first beam 21 by 180° with the head support portion 16 interposed therebetween. The second beam 22 extends from the second base portion 14 toward the head support portion 16.

[0028] As shown in FIG. 1, in a plan view of the head driving device 10A, the planar shape of the first beam 21 is a tapered shape whose width decreases from the base 21a to the tip 21b of the first beam 21. The "planar shape" referred to in this specification is the shape when the substrate 11 is viewed from the direction facing the surface of the substrate 11. The planar shape of the second beam 22 is also a tapered shape whose width decreases from the base 22a to the tip 22b of the second beam 22.

[0029] A first base-side hinge portion 31 is formed between the base 21a of the first beam 21 and the first base portion 13. The width W1 (shown in FIG. 3) of the first base-side hinge portion 31 is smaller than the width W2 of the base 21a of the first beam 21. The first base-side hinge portion 31 connects the base 21a of the first beam 21 and the first base portion 13 to each other. Element accommodating portions 32 and 33 each formed of a recess are formed on both sides of the first base-side hinge portion 31.

[0030] A first head-side hinge portion 35 is provided between the tip 21b of the first beam 21 and the head support portion 16. Slits 36 and 37 are formed on both sides of the first head-side hinge portion 35. The width of the first head-side hinge portion 35 is the same as or smaller than the width of the tip 21b of the first beam 21. The first head-side hinge portion 35 connects the tip 21b of the first beam 21 and the head support portion 16 to each other.

[0031] A second base-side hinge portion 41 is provided between the base 22a of the second beam 22 and the second base portion 14. The width W3 (shown in FIG. 3) of the second base-side hinge portion 41 is smaller than the width W4 of the base 22a of the second beam 22. The second base-side hinge portion 41 connects the base 22a of the second beam 22 and the second base portion 14 to each other. Element accommodating portions 42 and 43 each formed of a recess are formed on both sides of the second base-side hinge portion 41.

[0032] A second head-side hinge portion 45 is provided between the tip 22b of the second beam 22 and the head support portion 16. Slits 46 and 47 are formed on both sides of the second head-side hinge portion 45. The width of the second head-side hinge portion 45 is the same as or smaller than the width of the tip 22b of the second beam 22. The second head-side hinge portion 45 connects the tip 22b of the second beam 22 and the head support portion 16 to each other.

[0033] A first piezoelectric unit 51 is disposed between the first base portion 13 and the base portion 21a of the first beam 21. The first piezoelectric unit 51 includes a pair of first piezoelectric elements 51a and 51b. These piezoelectric elements 51a and 51b are made of a piezoelectric material, such as PZT (lead zirconate titanate), which deforms when a voltage is applied. The first piezoelectric elements 51a and 51b are respectively inserted into the first element accommodating portions 32 and 33 and fixed to the substrate 11 with an electrically insulating adhesive.

[0034] FIG. 4 is a cross-sectional view taken along line F4-F4 in FIG. 1, showing one of the element accommodating portions 32 and the piezoelectric element 51a. The thickness t1 of the piezoelectric element 51a is smaller than the thickness t2 of the substrate 11. An example of the thickness t1 of the piezoelectric element 51a is 0.1 mm, but other thicknesses may also be used. A first electrode 55 made of a metal thin film is formed on one surface of the piezoelectric element 51a. A second electrode 56 made of a metal thin film is formed on the other surface of the piezoelectric element 51a. When a voltage is applied to these electrodes 55 and 56, the piezoelectric element 51a deforms (expands and contracts) according to the direction of the flowing current. The directions in which the piezoelectric elements 51a and 51b expand and contract are the length direction of the first beam 21. The structures of the piezoelectric elements 51a and 51b are common to each other.

[0035] One of the piezoelectric elements 51a is accommodated in the element accommodating portion 32 with a predetermined polarity so as to expand or contract according to the polarity (plus or minus) of the applied voltage. In the case of this embodiment (FIG. 1), the other piezoelectric element 51b shown by hatching is accommodated in the element accommodating portion 33 with its orientation reversed so that its polarity is opposite to that of the one piezoelectric element 51a.

[0036] When one piezoelectric element 51a contracts and the other piezoelectric element 51b expands due to the application of voltage, the tip 21b of the first beam 21 is displaced in the first direction (indicated by arrow Y1 in FIG. 1). When one piezoelectric element 51a expands and the other piezoelectric element 51b contracts, the tip 21b of the first beam 21 is displaced in the second direction (indicated by arrow Y2 in FIG. 1).

[0037] A second piezoelectric unit 61 is disposed between the second base portion 14 and the base portion 22a of the second beam 22. The second piezoelectric unit 61 includes a pair of second piezoelectric elements 61a, 61b. These piezoelectric elements 61a, 61b are respectively inserted into the second element accommodating portions 42, 43 and fixed to the substrate 11 by an electrically insulating adhesive. The second piezoelectric elements 61a, 61b are made of a piezoelectric body having the same structure as the first piezoelectric elements 51a, 51b.

[0038] One piezoelectric element 61a of the second piezoelectric unit 61 shown in FIG. 1 is accommodated in the element accommodating portion 42 with a predetermined polarity so as to expand or contract according to the polarity (plus or minus) of the applied voltage. In contrast, the other piezoelectric element 61b shown by hatching is accommodated in the element accommodating portion 43 with its orientation reversed so that its polarity is opposite to that of one piezoelectric element 61a.

[0039] When one piezoelectric element 61a contracts and the other piezoelectric element 61b expands due to the application of voltage, the tip 22b of the second beam 22 is displaced in the first direction (indicated by arrow Y1 in FIG. 1). When one piezoelectric element 61a expands and the other piezoelectric element 61b contracts, the tip 22b of the second beam 22 is displaced in the second direction (indicated by arrow Y2). By displacing the tip 22b of the second beam 22 in the same direction as the tip 21b of the first beam 21 in this way, the head member 17 moves in the first direction Y1 or the second direction Y2.

[0040] The first suspension SP1 is constituted by the first beam 21, the first base-side hinge portion 31, and the first head-side hinge portion 35. The second suspension SP2 is constituted by the second beam 22, the second base-side hinge portion 41, and the second head-side hinge portion 45. The milli-actuator assembly MA1 is constituted by these suspensions SP1, SP2, the head support portion 16, the first piezoelectric unit 51, and the second piezoelectric unit 61.

[0041] The first suspension SP1 and the second suspension SP2 are line-symmetrical with respect to the axis C2 (shown in FIG. 3) passing through the center C1 of the head support portion 16 as the axis of symmetry. The first beam 21 and the second beam 22 extend in directions perpendicular to the axis C2, respectively. The first suspension SP1 and the second suspension SP2 are made of a common stainless-steel substrate 11. The thickness of the first suspension SP1 and the thickness of the second suspension SP2 are the same.

[0042] [Second - Fifth Embodiments] (FIGS. 5 - 9) FIG. 5 shows the head driving device 10B according to the second embodiment. FIG. 6 is a cross-sectional view of the head driving device 10B taken along the line F6 - F6 in FIG. 5. The head driving device 10B has a damper member DM1. Regarding the other configurations, since this head driving device 10B is common to the head driving device 10A of the first embodiment, the same reference numerals are given to the common components of both, and the description thereof is omitted.

[0043] As shown in FIG. 6, the damper member DM1 has a viscoelastic material layer 70 and a constrained plate 71. The viscoelastic layer 70 is made of a polymer material (for example, an acrylic resin) that can exhibit viscous resistance when deformed and has adhesiveness. The constrained plate 71 is made of a synthetic resin such as polyester and overlaps the viscoelastic layer 70.

[0044] The damper member DM1 shown in FIG. 5 is arranged to cover the head support portion 16, the entirety of the first beam 21, and the entirety of the second beam 22. For convenience of explanation, in FIG. 5, the damper member DM1 is represented by hatching. As shown in FIG. 6, the damper member DM1 also covers the slits 36, 37, 46, 47.

[0045] FIG. 7 shows a head driving device 10C according to a third embodiment. This head driving device 10C also has a damper member DM2. For convenience of explanation, the damper member DM2 is represented by hatching. The damper member DM2 of the third embodiment is arranged from the head support portion 16 to the middle in the longitudinal direction of the first beam 21 and from the head support portion 16 to the middle in the longitudinal direction of the second beam 22. Regarding other configurations, since the head driving device 10C of the third embodiment is common to the head driving device 10B of the second embodiment, common reference numerals are given to the common components of both, and the description thereof is omitted. The damper member DM2 is arranged on at least a part of the head support portion 16, the first beam 21, and the second beam 22.

[0046] FIG. 8 shows a head driving device 10D according to a fourth embodiment. This head driving device 10D has a pair of damper members DM3 arranged separately on the first beam 21 and the second beam 22. No damper member is provided on the head support portion 16. When no damper member is provided on the head support portion 16 as in this embodiment, the damper member may be attached to either the front or back surface of the first beam 21 and the second beam 22. Regarding other configurations, since the head driving device 10D according to the fourth embodiment is common to the head driving device 10B of the second embodiment, common reference numerals are given to the common components of both, and the description thereof is omitted.

[0047] FIG. 9 shows a head driving device 10E according to the fifth embodiment. The damper member DM4 of this head driving device 10E is arranged to cover the head support portion 16, the entire first beam 21, and the entire second beam 22. The damper member DM4 does not cover the slits 36, 37, 46, and 47. Regarding other configurations, since the head driving device 10E according to the fifth embodiment is common to the head driving device 10B of the second embodiment, the same reference numerals are given to the common components of both, and the description thereof is omitted.

[0048] As shown in FIG. 10, it may have a first bending portion 75 formed on the first suspension SP1 and a second bending portion 76 formed on the second suspension SP2. The first bending portion 75 is bent at an angle θ1 of 90° or less with respect to the head support portion 16 in the thickness direction of the substrate 11. The second bending portion 76 is bent at the same angle θ2 as the first bending portion 75 on the same side as the first bending portion 75 with respect to the head support portion 16. This head driving device has a mountain-shaped three-dimensional shape due to having the bending portions 75 and 76.

[0049] FIG. 11 shows the vibration characteristics of the first mode in the range of 0 - 1.5 KHz for the head driving devices 10A - 10E according to the first to fifth embodiments. The horizontal axis in FIG. 11 is the frequency, and the vertical axis is the gain.

[0050] The dashed line N1 in FIG. 11 shows the vibration characteristics of the head driving device 10A of the first embodiment that does not have a damper member. The one-dot chain line DM1 in FIG. 11 shows the vibration characteristics of the head driving device 10B (FIG. 5) provided with the damper member DM1 of the second embodiment. The two-dot chain line DM2 shows the vibration characteristics of the head driving device 10C (FIG. 7) provided with the damper member DM2 of the third embodiment. The thin line DM3 shows the vibration characteristics of the head driving device 10D (FIG. 8) provided with the damper member DM3 of the fourth embodiment. The solid line DM4 shows the vibration characteristics of the head driving device 10E (FIG. 9) provided with the damper member DM4 of the fifth embodiment.

[0051] As shown by the dashed line N1 in FIG. 11, the resonance peak of the head driving device of the first embodiment without a damper member is sharp. In contrast, for the head driving devices of the second to fifth embodiments having a damper member, the resonance peaks are all gentle. In particular, the resonance peak of the head driving device 10E (FIG. 9) of the fifth embodiment shown by the solid line DM4 is minimized. Therefore, for the vibration characteristics in the range of 0 - 1.5 KHz, the damper member DM4 (FIG. 9) of the fifth embodiment may be desirable.

[0052] FIG. 12 shows the vibration characteristics of the first mode in the range of 8 - 9.5 KHz for the head driving devices 10A - 10E according to the first to fifth embodiments. The horizontal axis in FIG. 12 represents the frequency, and the vertical axis represents the gain.

[0053] The dashed line N1 in FIG. 12 shows the vibration characteristics of the head driving device 10A of the first embodiment without a damper member. The one-dot chain line DM1 in FIG. 12 shows the vibration characteristics of the head driving device 10B (FIG. 5) provided with the damper member DM1 of the second embodiment. The two-dot chain line DM2 shows the vibration characteristics of the head driving device 10C (FIG. 7) provided with the damper member DM2 of the third embodiment. The thin line DM3 shows the vibration characteristics of the head driving device 10D (FIG. 8) provided with the damper member DM3 of the fourth embodiment. The solid line DM4 shows the vibration characteristics of the head driving device 10E (FIG. 9) provided with the damper member DM4 of the fifth embodiment.

[0054] As shown by the dashed line N1 in FIG. 12, the resonance peak of the head driving device of the first embodiment without a damper member is large. In contrast, for the head driving devices of the second to fifth embodiments having a damper member, the resonance peaks are all small. In particular, the resonance modes of the head driving device 10B having the damper member DM1 of the second embodiment (FIG. 5) and the head driving device 10C having the damper member DM2 of the third embodiment (FIG. 7) are almost flat. Therefore, for the vibration characteristics in the range of 8 - 9.5 KHz, the damper member DM1 of the second embodiment and the damper member DM2 of the third embodiment may be desirable.

[0055] [Comparative Example 1] (Fig. 13(A)) Fig. 13(A) shows the head driving device 10F of Comparative Example 1. The damper member DM5 of this head driving device 10F has a first extending portion 81 and a second extending portion 82. The first extending portion 81 extends from the first base-side hinge portion 31 to the first base portion 13. The second extending portion 82 extends from the second base-side hinge portion 41 to the second base portion 14. Regarding other configurations, the head driving device 10F of Comparative Example 1 is common with the head driving device 10B of the second embodiment. The vibration characteristics of the head driving device 10F of Comparative Example 1 were equivalent to those of the head driving device 10B of the second embodiment. However, the damper member DM5 of Comparative Example 1 has the drawbacks that its shape is more complex and its weight is larger compared with the damper member DM1 of the second embodiment.

[0056] [Comparative Example 2] (Fig. 13(B)) Fig. 13(B) shows the head driving device 10G of Comparative Example 2. The damper member DM6 of this head driving device 10G has an extending portion 83 covering the first piezoelectric unit 51 and an extending portion 84 covering the second piezoelectric unit 61. Regarding other configurations, the head driving device 10G of Comparative Example 2 is common with the head driving device 10B of the second embodiment. The vibration characteristics of the head driving device 10G of Comparative Example 2 were such that the first mode was larger compared with the head driving device 10B of the second embodiment. Moreover, the damper member DM6 of Comparative Example 2 has the drawback that its weight is larger compared with the damper member DM1 of the second embodiment. From the above, it was found that it is better to provide the damper member so as not to cover the base-side hinge portions 31, 41 and the piezoelectric units 51, 61.

[0057] [Sixth Embodiment] (Figs. 14 - 15) Hereinafter, the head driving device 10H according to the sixth embodiment will be described with reference to Figs. 14 and 15. Fig. 14 is a perspective view of the head driving device 10H, and Fig. 15 is a plan view of the head driving device 10H.

[0058] The head driving device 10H includes a first milli-actuator assembly MA1 and a second milli-actuator assembly MA2. The first milli-actuator assembly MA1 is configured in the same manner as the milli-actuator assembly MA1 of the first embodiment (Figs. 1-4). Therefore, the second milli-actuator assembly MA2 will be described below.

[0059] The second milli-actuator assembly MA2 shown in Figs. 14 and 15 includes a third suspension SP3 and a fourth suspension SP4. The configuration of the third suspension SP3 is common to the first suspension SP1. The configuration of the fourth suspension SP4 is common to the second suspension SP2.

[0060] A first head support portion 16 and a second head support portion 116 are arranged at the center between the first base portion 13 and the second base portion 14. The second head support portion 116 is provided at a different position in the length direction of the head member 17 with respect to the first head support portion 16. The head member 17 is supported by these first head support portion 16 and second head support portion 116. The head member 17 is fixed to the first head support portion 16 and the second head support portion 116 by fixing means such as an adhesive.

[0061] The second milli-actuator assembly MA2 includes a second head support portion 116, a third beam 121, and a fourth beam 122. The third beam 121 extends from the first base portion 13 toward the second head support portion 116. The fourth beam 122 is provided on the side opposite to the third beam 121 by 180° with the second head support portion 116 interposed therebetween. The fourth beam 122 extends from the second base portion 14 toward the second head support portion 116.

[0062] In the plan view of the head driving device 10H as shown in FIG. 15, the planar shape of the third beam 121 is a tapered shape in which the width decreases from the base 121a to the tip 121b of the third beam 121. The planar shape of the fourth beam 122 is also a tapered shape in which the width decreases from the base 122a to the tip 122b of the fourth beam 122.

[0063] A third base-side hinge portion 131 is formed between the base 121a of the third beam 121 and the first base portion 13. The width of the third base-side hinge portion 131 is smaller than the width of the base 121a of the third beam 121. The third base-side hinge portion 131 connects the base 121a of the third beam 121 and the first base portion 13 to each other. Element accommodating portions 132 and 133 formed of recesses are formed on both sides of the third base-side hinge portion 131.

[0064] A third head-side hinge portion 135 is provided between the tip 121b of the third beam 121 and the second head support portion 116. Slits 136 and 137 are formed on both sides of the third head-side hinge portion 135. The width of the third head-side hinge portion 135 is the same as or smaller than the width of the tip 121b of the third beam 121. The third head-side hinge portion 135 connects the tip 121b of the third beam 121 and the second head support portion 116 to each other.

[0065] A fourth base-side hinge portion 141 is provided between the base 122a of the fourth beam 122 and the second base portion 14. The width of the fourth base-side hinge portion 141 is smaller than the width of the base 122a of the fourth beam 122. The fourth base-side hinge portion 141 connects the base 122a of the fourth beam 122 and the second base portion 14 to each other. Element accommodating portions 142 and 143 formed of recesses are formed on both sides of the fourth base-side hinge portion 141.

[0066] A fourth head-side hinge portion 145 is provided between the tip 122b of the fourth beam 122 and the second head support portion 116. Slits 146 and 147 are formed on both sides of the fourth head-side hinge portion 145. The width of the fourth head-side hinge portion 145 is the same as or smaller than the width of the tip 122b of the fourth beam 122. The fourth head-side hinge portion 145 connects the tip 122b of the fourth beam 122 and the second head support portion 116 to each other.

[0067] A third piezoelectric unit 151 is disposed between the first base portion 13 and the base 121a of the third beam 121. The third piezoelectric unit 151 includes a pair of piezoelectric elements 151a and 151b. The piezoelectric elements 151a and 151b are made of a piezoelectric material, such as PZT (lead zirconate titanate), which deforms when a voltage is applied. The piezoelectric elements 151a and 151b are respectively inserted into element housing portions 132 and 133 and fixed to the substrate 11 by an electrically insulating adhesive.

[0068] The piezoelectric elements 151a and 151b expand or contract according to the polarity (plus or minus) of the applied voltage. For example, when one piezoelectric element 151a expands and the other piezoelectric element 151b contracts, the tip 121b of the third beam 121 is displaced in the first direction. When one piezoelectric element 151a contracts and the other piezoelectric element 151b expands, the tip 121b of the third beam 121 is displaced in the second direction.

[0069] A fourth piezoelectric unit 161 is disposed between the second base portion 14 and the base 122a of the fourth beam 122. The fourth piezoelectric unit 161 includes a pair of piezoelectric elements 161a and 161b. These piezoelectric elements 161a and 161b are respectively inserted into element housing portions 142 and 143 and fixed to the substrate 11 by an electrically insulating adhesive.

[0070] The third suspension SP3 is constituted by the third beam 121, the third base-side hinge portion 131, and the third head-side hinge portion 135. The fourth suspension SP4 is constituted by the fourth beam 122, the fourth base-side hinge portion 141, and the fourth head-side hinge portion 145. The second milli-actuator assembly MA2 is constituted by these suspensions SP3 and SP4, the second head support portion 116, the third piezoelectric unit 151, and the fourth piezoelectric unit 161.

[0071] The third suspension SP3 and the fourth suspension SP4 are line-symmetrical with the axis C4 (shown in FIG. 15) passing through the center C3 of the second head support portion 116 as the axis of symmetry. The axis C4 also passes through the center C1 of the first head support portion 16. The third beam 121 and the fourth beam 122 extend in directions perpendicular to the axis C4, respectively. The third suspension SP3 and the fourth suspension SP4 are made of a common stainless-steel substrate 11. The thickness of the third suspension SP3 is the same as the thickness of the fourth suspension SP4.

[0072] As described above, the head member 17 of the head driving device 10H of the sixth embodiment is supported by the first milli-actuator assembly MA1 and the second milli-actuator assembly MA2 at two locations in the longitudinal direction of the head member 17. Therefore, with respect to the three-dimensional directions (the directions of the X-axis, Y-axis, and Z-axis) shown in FIG. 14, the rigidity of the head driving device 10H can be increased, and the head member 17 can be stabilized.

[0073] The piezoelectric elements 51b, 61b, 151b, and 161b shown in FIGS. 14 and 15 are accommodated in the element accommodating portions 33, 43, 133, and 143 in a predetermined orientation with respect to the polarity. On the other hand, the piezoelectric elements 51a, 61a, 151a, and 161a shown by hatching are accommodated in the element accommodating portions 32, 42, 132, and 142 with their orientations reversed so that the polarities are reversed.

[0074] As shown in Fig. 15, when an input voltage [+y] is applied to all the piezoelectric elements, the positive-position piezoelectric elements 51b, 61b, 151b, 161b expand, and the inverted-state piezoelectric elements 51a, 61a, 151a, 161a contract. As a result, the head member 17 moves in the first direction (indicated by arrow Y1).

[0075] Conversely to Fig. 15, when an input voltage [-y] is applied to all the piezoelectric elements, the positive-position piezoelectric elements 51b, 61b, 151b, 161b contract, and the inverted-state piezoelectric elements 51a, 61a, 151a, 161a expand. As a result, the head member 17 moves in the second direction (the direction opposite to arrow Y1). Thus, in the case of this embodiment, the head member 17 can be moved in the Y-axis direction by one set of input signals [±y].

[0076] [Seventh Embodiment] (Fig. 16) Fig. 16 shows a head driving device 10J of the seventh embodiment. The structures of the piezoelectric elements 51a, 51b, 61a, 61b, 151a, 151b, 161a, 161b are common to each other. The piezoelectric elements 51a, 51b, 161a, 161b are housed in the element housing portions 32, 33, 142, 143 in a predetermined direction with respect to the polarity. On the other hand, the piezoelectric elements 61a, 61b, 151a, 151b indicated by hatching are housed in the element housing portions 42, 43, 132, 133 with their directions reversed so that the polarities are reversed. The other configurations are common to the sixth embodiment (Figs. 14 and 15).

[0077] As shown in Fig. 16, when an input voltage [+x] is applied to all the piezoelectric elements, the positive-position piezoelectric elements 51a, 51b, 161a, 161b expand, and the inverted-state piezoelectric elements 61a, 61b, 151a, 151b contract. As a result, the head member 17 is displaced in the skew direction indicated by arrow X in Fig. 16.

[0078] Conversely, when an input voltage [-x] is applied to all the piezoelectric elements, the piezoelectric elements 51a, 51b, 161a, 161b in the normal orientation contract, and the piezoelectric elements 61a, 61b, 151a, 151b in the inverted state expand. As a result, the head member 17 moves in the skew direction opposite to the arrow X. In this way, the head member 17 can be driven in the skew direction by a single input signal [±x].

[0079] [Eighth Embodiment] (FIG. 17) FIG. 17 shows a head driving device 10K according to the eighth embodiment. The configuration of this head driving device 10K is common to the head driving device 10J of the seventh embodiment (FIG. 16). The piezoelectric elements 51a, 51b, 161a, 161b are housed in the element housing portions 32, 33, 142, 143 in a predetermined orientation with respect to their polarities. The piezoelectric elements 61a, 61b, 151a, 151b shown by hatching are housed in the element housing portions 42, 43, 132, 133 with their polarities reversed.

[0080] As shown in FIG. 17, when an input voltage [x + y] is applied to the piezoelectric elements 51b, 61a, 151a, 161b and an input voltage [x - y] is applied to the piezoelectric elements 51a, 61b, 151b, 161a, the head member 17 moves in the skew direction indicated by the arrow X and also moves in the first direction (indicated by the arrow Y1).

[0081] Conversely, when an input voltage [-x - y] is applied to the piezoelectric elements 51b, 61a, 151a, 161b and an input voltage [-x + y] is applied to the piezoelectric elements 51a, 61b, 151b, 161a, the head member 17 moves in the direction opposite to the arrow X and also moves in the direction opposite to the arrow Y. In this way, the head member 17 can be driven in the skew direction and the Y-axis direction by two input signals.

[0082] [Ninth Embodiment] (FIGS. 18 - 23) FIG. 18 schematically shows a data storage device 200 including a head drive device 10L according to the ninth embodiment. An example of the data storage device 200 includes a case 201, an actuator assembly 202, a first take-up device 203, a second take-up device 204, and a plurality of guide rollers 205. Note that the data storage device 200 is not limited to the example shown in FIG. 18, and can be configured in various forms as necessary.

[0083] A tape 18 as a recording medium is wound around tape reels 210 and 211. A head member 17 is provided in the actuator assembly 202. The actuator assembly 202 has a function of moving the head member 17 in the width direction (Y-axis direction) and the skew direction of the tape 18. Access (data writing or reading) to the tape 18 is performed by the head member 17.

[0084] An example of the actuator assembly 202 including the head drive device 10L is shown in FIG. 19. A two-way arrow PT1 in FIG. 19 indicates the pitching direction of the head member 17. FIG. 20 is a perspective view showing the actuator assembly 202 disassembled. FIG. 21 is a view of the head drive device 10L as seen from the direction indicated by an arrow F21 in FIG. 19.

[0085] The actuator assembly 202 includes a slide member 222 movable along a pair of guide members 220 and 221, voice coil motors 223 and 224 for coarse movement to move the slide member 222, a skew drive block 225 attached to the slide member 222, and the head drive device 10L. The skew drive block 225 can rotate in the skew direction about a skew axis 226.

[0086] The pair of voice coil motors 223 and 224 each have a yoke 230, 231, a magnet 232, 233, and a coil 234, 235. The voice coil motors 223 and 224 move the slide member 222, the head drive device 10L, and the skew drive block 225 along the guide members 220 and 221. The voice coil motors 223 and 224 also rotate the head drive device 10L and the skew drive block 225 about the skew axis 226.

[0087] As shown in FIG. 21, the head drive device 10L has a three-dimensional first milli-actuator assembly MA1' having a first bent portion 241 and a second bent portion 242, and a three-dimensional second milli-actuator assembly MA2' having a third bent portion 243 and a fourth bent portion 244. The first milli-actuator assembly MA1' and the second milli-actuator assembly MA2' have a common configuration with each other.

[0088] The first milli-actuator assembly MA1' is configured in the same manner as the milli-actuator assembly MA1 of the sixth embodiment (FIGS. 14 and 15), except that it has the bent portions 241 and 242. The second milli-actuator assembly MA2' is configured in the same manner as the milli-actuator assembly MA2 of the sixth embodiment (FIGS. 14 and 15), except that it has the bent portions 243 and 244. For the milli-actuator assemblies MA1' and MA2', the same reference numerals are given to the common parts as those of the milli-actuator assemblies MA1 and MA2 of the sixth embodiment, and the description thereof is omitted.

[0089] As shown in FIG. 21, a first bending portion 241 is formed in the first head-side hinge portion 35. A second bending portion 242 is also formed in the second head-side hinge portion 45. The first bending portion 241 is bent at an angle θ1 (for example, 45°) smaller than 90° in the thickness direction of the substrate 11 with respect to the first head support portion 16. The second bending portion 242 is bent at the same angle θ2 (for example, 45°) as the first bending portion 241 on the same side as the first bending portion 241 in the thickness direction of the substrate 11 with respect to the first head support portion 16.

[0090] A third bending portion 243 (shown in FIGS. 19 and 20) is bent at the same angle θ1 (for example, 45°) as the first bending portion 241 in the same direction as the first bending portion 241 in the thickness direction of the substrate 11 with respect to the second head support portion 116. The third bending portion 243 is formed in the third head-side hinge portion 135. The fourth bending portion 244 is bent at the same angle θ2 (for example, 45°) as the third bending portion 243 on the same side as the third bending portion 243 in the thickness direction of the substrate 11 with respect to the second head support portion 116. The fourth bending portion 244 is formed in the fourth head-side hinge portion 145.

[0091] The head driving device 10L of the present embodiment has a three-dimensional shape forming a chevron shape by providing the bending portions 241, 242, 243, and 244. Therefore, the head driving device 10L of the present embodiment can increase rigidity as compared with the head driving device 10H of the sixth embodiment (FIGS. 14 and 15) having a planar shape.

[0092] As shown in FIG. 22, a terminal portion 300 is provided in the frame portion 12 of the head driving device 10L. A terminal portion 301 is also provided in the head member 17. Terminals 310, 311, 312, and 313 are provided in the piezoelectric elements 61a, 61b, 161a, and 161b, respectively. The terminal portion 300 of the frame portion 12 is electrically connected to the terminal portion 301 of the head member 17 and the terminals 310, 311, 312, and 313 of the piezoelectric elements 61a, 61b, 161a, and 161b.

[0093] FIG. 23 shows the vibration characteristics of the head driving device 10L of the ninth embodiment (FIGS. 19-22) and the vibration characteristics of the head driving device 10H of the sixth embodiment (FIG. 14). The solid line in FIG. 23 represents the vibration characteristics of the head driving device 10L having the bent portions 241, 242, 243, 244 at 45°. The dashed line in FIG. 23 represents the vibration characteristics of the head driving device 10H without a bent portion.

[0094] R1 in FIG. 23 is the pitching mode of the head driving device 10H without a bent portion, which occurs around 1 kHz. R2 in FIG. 23 is the pitching mode of the head driving device 10L having a bent portion, which occurs around 11 kHz. According to the three-dimensional head driving device 10L having a bent portion, the frequency of the pitching mode can be significantly increased as compared with the frequency of the planar head driving device 10H.

[0095] As shown in FIG. 24, a connection portion 270 connecting the first head support portion 16 and the second head support portion 116 may be provided. By providing the connection portion 270, the positional relationship between the first head support portion 16 and the second head support portion 116 is stabilized. Therefore, when bending the bent portions 241, 242, 243, 244, it is possible to suppress a change in the positions of the first head support portion 16 and the second head support portion 116. Further, by providing the connection portion 270, the adhesiveness of the head member 17 can be increased. It is also possible to support the head member 17 in a stable state using the connection portion 270.

[0096] FIG. 25 shows a head driving device 10M according to the tenth embodiment. This head driving device 10M includes a first microactuator assembly MA1, a second microactuator assembly MA2, and a third microactuator assembly MA3. The third microactuator assembly MA3 includes a third head support portion 416, a fifth beam 421, a sixth beam 422, a fifth piezoelectric unit 451, and a sixth piezoelectric unit 461.

[0097] The third head support portion 416 is provided between the first base portion 13 and the second base portion 14 and supports the head member 17. The fifth beam 421 extends from the first base portion 13 toward the third head support portion 416. The first base portion 13 and the base of the fifth beam 421 are connected by a fifth base-side hinge portion 431. The tip of the fifth beam 421 and the third head support portion 416 are connected by a fifth head-side hinge portion 435.

[0098] The sixth beam 422 is provided on the side opposite to the fifth beam 421 with the third head support portion 416 interposed therebetween. The sixth beam 422 extends from the second base portion 14 toward the third head support portion 416. The second base portion 14 and the base of the sixth beam 422 are connected by a sixth base-side hinge portion 441. The tip of the sixth beam 422 and the third head support portion 416 are connected by a sixth head-side hinge portion 445.

[0099] The fifth piezoelectric unit 451 is disposed between the first base portion 13 and the base of the fifth beam 421. The fifth piezoelectric unit 451 deforms when a voltage is applied thereto, thereby displacing the tip of the fifth beam 421. The sixth piezoelectric unit 461 is disposed between the second base portion 14 and the base of the sixth beam 422. The sixth piezoelectric unit 461 deforms when a voltage is applied thereto, thereby displacing the tip of the sixth beam 422.

[0100] The configurations of the milli-actuator assemblies MA1, MA2, and MA3 are common to each other and are configured in the same manner as the milli-actuator assembly MA1 shown in FIGS. 14 and 15. The head driving device 10M of the present embodiment includes three milli-actuator assemblies MA1, MA2, and MA3, so that the rigidity can be further increased. By providing bending portions 241, 242, 243, and 244 similar to those of the head driving device 10L of the sixth embodiment in these milli-actuator assemblies MA1, MA2, and MA3, a three-dimensional shape may be formed. The number of milli-actuator assemblies may be four or more.

[0101] As shown in FIG. 26, it may have a connecting portion 470 that connects the first head support portion 16, the second head support portion 116, and the third head support portion 416. By providing the connecting portion 470, the positional relationship of the head support portions 16, 116, 416 can be kept constant with respect to each other.

[0102] Needless to say, in practicing the present invention, the specific modes of each element constituting the head driving device can be variously changed and implemented. Also, the data storage device can take various forms as necessary.

Explanation of Reference Numerals

[0103] 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10J, 10K, 10L, 10M... head drive device, 11... substrate, 12... frame portion, 13... first base portion, 14... second base portion, 16... head support portion (first head support portion), 17... head member (slider), 18... magnetic tape, 21... first beam, 21a... base portion, 21b... tip, 22... second beam, 22a... base portion, 22b... tip, 31... first base side hinge portion, 32, 33... element housing portions, 35... first head side hinge portion, 36, 37... slits, 41... second base side hinge portion, 42, 43... element housing portions, 45... second head side hinge portion, 46, 47... slits, 51... first piezoelectric unit, 51a, 51b... piezoelectric elements, 61... second piezoelectric unit, 61a, 61b... piezoelectric elements, SP1, SP2, SP3, SP4... suspensions, MA1, MA2, MA3... microactuator assemblies, DM1, DM2, DM3, DM4, DM5, DM6... damper members, 116... second head support portion, 121... third beam, 121a... base portion, 121b... tip, 122... fourth beam, 122a... base portion, 122b... tip, 131... third base side hinge portion, 132, 133... element housing portions, 135... third head side hinge portion, 136, 137... slits, 141... fourth base side hinge portion, 142, 143... element housing portions, 145... fourth head side hinge portion, 146, 147... slits, 151... third piezoelectric unit, 151a, 151b... piezoelectric elements, 161... fourth piezoelectric unit, 161a, 161b... piezoelectric elements, 200... data storage device, 202... actuator assembly, 241, 242, 243, 244... bending portions.

Claims

1. A head driving device for driving a head member, comprising: a first base portion and a second base portion that face each other and are spaced apart from each other; a head support portion provided between the first base portion and the second base portion for supporting the head member; a first beam extending from the first base portion toward the head support portion; a first base-side hinge portion connecting the base of the first beam and the first base portion; a first head-side hinge portion connecting the tip of the first beam and the head support portion; a second beam that exists on the side opposite to the first beam with the head support portion interposed therebetween and extends from the second base portion toward the head support portion; a second base-side hinge portion connecting the base of the second beam and the second base portion; a second head-side hinge portion connecting the tip of the second beam and the head support portion; a first piezoelectric unit disposed between the first base portion and the base of the first beam, which displaces the tip of the first beam by deforming when a voltage is applied; a second piezoelectric unit disposed between the second base portion and the base of the second beam, which displaces the tip of the second beam by deforming when a voltage is applied; A head driving device characterized by comprising the above.

2. In the head driving device according to Claim 1, the width of the first base-side hinge portion is smaller than the width of the base of the first beam, the width of the first head-side hinge portion is smaller than the width of the tip of the first beam, the width of the second base-side hinge portion is smaller than the width of the base of the second beam, A head driving device in which the width of the second head-side hinge portion is smaller than the width of the tip of the second beam.

3. In the head driving device according to Claim 2, the planar shape of the first beam is a shape in which the width becomes smaller from the base of the first beam toward the tip of the first beam, A head driving device in which the planar shape of the second beam is a shape in which the width becomes smaller from the base of the second beam toward the tip of the second beam.

4. In the head driving device according to Claim 2, first element accommodating portions are provided on both sides of the first base-side hinge portion, and a pair of first piezoelectric elements constituting the first piezoelectric unit are disposed in these first element accommodating portions. A head driving device having second element accommodating portions on both sides of the second base-side hinge portion, and a pair of second piezoelectric elements constituting the second piezoelectric unit disposed in these second element accommodating portions.

5. In the head driving device according to claim 4, one of the pair of first piezoelectric elements is disposed with a predetermined polarity, the other of the pair of first piezoelectric elements is disposed with its orientation reversed so that the polarity is opposite, one of the pair of second piezoelectric elements is disposed with a predetermined polarity, A head driving device in which the other of the pair of second piezoelectric elements is disposed with its orientation reversed so that the polarity is opposite.

6. In the head driving device according to claim 1, a first suspension made of a metal substrate and including the first beam, the first base-side hinge portion, and the first head-side hinge portion, a second suspension made of the substrate and including the second beam, the second base-side hinge portion, and the second head-side hinge portion, and being line-symmetric with the first suspension with an axis passing through the center of the head support portion as the axis of symmetry, A head driving device comprising the same.

7. In the head driving device according to claim 6, a first bending portion formed in the first suspension and bending at an angle of 90° or less in the thickness direction of the substrate with respect to the head support portion, a second bending portion formed in the second suspension and bending on the same side as the first bending portion with respect to the head support portion, A head driving device having the same.

8. In the head driving device according to claim 1, A head driving device comprising a damper member disposed at least partially on the first beam, the second beam, and the head support portion.

9. A head driving device for driving a head member, a first base portion and a second base portion facing each other with a space therebetween, a first head support portion provided between the first base portion and the second base portion and supporting the head member, a first beam extending from the first base portion toward the first head support portion, a first base-side hinge portion connecting the base of the first beam and the first base portion, a first head-side hinge portion connecting the tip of the first beam and the first head support portion, a second beam existing on the side opposite to the first beam with the first head support portion interposed therebetween and extending from the second base portion toward the first head support portion, A second base-side hinge portion connecting the base of the second beam and the second base portion, A second head-side hinge portion connecting the tip of the second beam and the first head support portion, A first piezoelectric unit disposed between the first base portion and the base of the first beam, and displacing the tip of the first beam by deforming when a voltage is applied, A second piezoelectric unit disposed between the second base portion and the base of the second beam, and displacing the tip of the second beam by deforming when a voltage is applied, A second head support portion provided between the first base portion and the second base portion for supporting the head member, A third beam extending from the first base portion toward the second head support portion, A third base-side hinge portion connecting the base of the third beam and the first base portion, A third head-side hinge portion connecting the tip of the third beam and the second head support portion, A fourth beam provided on the side opposite to the third beam with the second head support portion interposed therebetween, and extending from the second base portion toward the second head support portion, A fourth base-side hinge portion connecting the base of the fourth beam and the second base portion, A fourth head-side hinge portion connecting the tip of the fourth beam and the second head support portion, A third piezoelectric unit disposed between the first base portion and the base of the third beam, and displacing the tip of the third beam by deforming when a voltage is applied, A fourth piezoelectric unit disposed between the second base portion and the base of the fourth beam, and displacing the tip of the fourth beam by deforming when a voltage is applied, A head driving device characterized by comprising the above.

10. In the head driving device according to Claim 9, A first suspension made of a metal substrate and including the first beam, the first base-side hinge portion, and the first head-side hinge portion, A second suspension made of the substrate and including the second beam, the second base-side hinge portion, and the second head-side hinge portion, and being line-symmetrical with the first suspension with an axis passing through the center of the first head support portion as the axis of symmetry, A third suspension made of the substrate and including the third beam, the third base-side hinge portion, and the third head-side hinge portion, A head driving device comprising the substrate, the fourth beam, the fourth base-side hinge portion, and the fourth head-side hinge portion, and having a fourth suspension that is line-symmetric with the third suspension with the axis passing through the center of the second head support portion as the axis of symmetry.

11. In the head driving device according to claim 10, a first bending portion formed in the first suspension and bent at an angle of 90° or less in the thickness direction of the substrate with respect to the first head support portion; a second bending portion formed in the second suspension and bent on the same side as the first bending portion at the same angle as the first bending portion with respect to the first head support portion; a third bending portion formed in the third suspension and bent on the same side as the first bending portion at the same angle as the first bending portion with respect to the second head support portion; a head driving device having a fourth bending portion formed in the fourth suspension and bent on the same side as the first bending portion at the same angle as the first bending portion with respect to the second head support portion.

12. In the head driving device according to claim 11, a head driving device having a connecting portion connecting the first head support portion and the second head support portion.

13. In the head driving device according to claim 9, further, a third head support portion provided between the first base portion and the second base portion and supporting the head member; a fifth beam extending from the first base portion toward the third head support portion; a fifth base-side hinge portion connecting the base of the fifth beam and the first base portion; a fifth head-side hinge portion connecting the tip of the fifth beam and the third head support portion; a sixth beam provided on the side opposite to the fifth beam with the third head support portion interposed therebetween and extending from the second base portion toward the third head support portion; a sixth base-side hinge portion connecting the base of the sixth beam and the second base portion; a sixth head-side hinge portion connecting the tip of the sixth beam and the third head support portion; a fifth piezoelectric unit disposed between the first base portion and the base of the fifth beam and displacing the tip of the fifth beam by deforming when a voltage is applied. A sixth piezoelectric unit that is disposed between the second base portion and the base portion of the sixth beam and that displaces the tip of the sixth beam by deforming when a voltage is applied. A head driving device characterized by comprising the same.

14. In the head driving device according to claim 13, A head driving device having a connecting portion that connects the first head support portion, the second head support portion, and the third head support portion.

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