JP2001023201A - Biaxial actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biaxial actuator capable of providing good workability during attaching of a printed circuit board, facilitating wiring, soldering and positioning of conductive material in the printed circuit board, and preventing any effects on a magnetic circuit and the rotation of the printed circuit board with respect to a fixed member. SOLUTION: A printed circuit board 16 is provided with soldering parts 16a to 16d for fixing the ends of suspension wires 13a to 13d by solder, and conductive contact parts 16k, 16m, 16n and 16p respectively connected to the soldering parts 16a to 16d, each soldering part and each conductive contact part are disposed in positions point-symmetrical with respect to one point of the center of the printed circuit board 16, and the conductive contact parts 16k, 16m, 16n and 16p are set as power supplied parts, to which power is supplied from a flexible board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biaxial actuator for an optical pickup used for recording or reproducing a signal on an optical disk, for example.

[0002]

2. Description of the Related Art Conventionally, CDs (compact discs) and DVDs (digital video discs or digital
An optical pickup is used for recording or reproducing an information signal on or from an optical disk such as a versatile disk. The optical pickup includes a light emitting element that emits a laser beam, a light receiving element that receives the laser beam, an optical system that guides the laser beam, and an objective lens that focuses the laser beam.

[0003] A laser beam emitted from a light emitting element is guided to an objective lens by an optical system, and is condensed by the objective lens. The objective lens is driven in the optical axis direction (focusing direction) of the objective lens and follows the information recording track so that the converged beam always focuses on the information recording surface of the optical disk with respect to surface deflection of the optical disk. When the objective lens is driven in the radial direction (tracking direction) of the optical disk as described above, the return light, which is the reflected light of the laser beam changed from the information recording surface of the optical disk according to the information signal, again passes through the objective lens and the optical system. The light is received by the light receiving element and converted into an output signal to reproduce the information signal or to record the information signal.

[0004] As an objective lens driving device described above, an electromagnetically driven actuator that is driven in two axes in a focusing direction and a tracking direction, that is, a biaxial actuator is used. The biaxial actuator includes a lens holder to which an objective lens is attached, a fixed part for supporting a lens holder that is a movable part, and a drive part for generating a driving force.

Hereinafter, an example of a conventional biaxial actuator will be described with reference to a partial perspective view shown in FIG. In the figure, a lens holder to which an objective lens, a focusing coil, and a tracking coil are fixed (none is shown)
Of the four suspension wires 50a to 50d, which are movably supported in two axes of the tracking (T) direction and the focusing (F) direction, are provided on the fixed member 90 at one end opposite to the lens holder. A soldering portion 96 having through holes (not shown) provided at four corners of a substantially rectangular printed circuit board 92 whose longitudinal direction is the T direction through 100
a to 96d, and are fixed by soldering. The printed circuit board 92 has a screw hole at the center thereof, and is screwed by a screw 94 to a fixing member 90 previously attached to a base member (not shown).

[0006] Also, four suspension wires 50a
50d to 50d are connected to both ends of the winding of the focusing coil and both ends of the winding of the tracking coil, respectively. Power is supplied to each coil through four suspension wires 50a to 50d. As a result, the magnetic field generated in the coils interacts with the magnetic field generated by the yoke provided on the base member and the magnet (both not shown) fixed to the yoke, thereby fixing the coils. One lens holder is shown in FIG.
It is driven in the middle F direction and the T direction.

On the other hand, the soldering portion 9 of the printed circuit board 92
From 6a to 96d, the conductive pattern 93 is wired to the mounting portion 92a which is formed to protrude from one side end along the longitudinal direction of the printed circuit board 92. And
In this mounting portion 92a, a flexible substrate 98 which is a conductor for electrical connection with a drive circuit (not shown)
Of the conductive patterns 93 are connected to each other, and are fixed by soldering.

In this way, power is supplied from the drive circuit to the focusing coil and the tracking coil through the flexible substrate 98. Specifically, each terminal 98a of the flexible substrate 98 is composed of two current supply units for supplying a current for a focusing coil and two current supply units for supplying a current for a tracking coil. The arrangement on the flexible substrate 98 is arbitrarily determined while matching the driving circuit.

[0009]

However, in the above-described conventional biaxial actuator, the printed circuit board 92 has a mounting portion 92a at one side end and the conductive pattern 93 has directionality. The mounting work had to be performed carefully so that the direction of 92 was not mistaken, and the workability was deteriorated.

The terminal 98a of the flexible substrate 98
When wiring to the mounting portion 92a of the printed circuit board 92,
The work was difficult because it had to be performed at the edge of the mounting portion 92a. Further, when soldering is performed thereafter, a space for mounting the flexible substrate 98 on the printed circuit board 92 is not available, and thus, it is difficult to solder. Also,
The positioning of the flexible board 98 with respect to the printed board 92 has also been difficult.

In supplying power to the focusing coil and the tracking coil through the soldering portions 96a to 96d, for example, as shown in FIG.
When the suspension wire 50b is connected to one of the current supply units for the focusing coil (represented by F + in the figure) and the other current supply unit for the focusing coil (represented by F- in the figure), the suspension wire 50b is connected to the suspension wire 50b. A current i1 flows to the focusing coil, and then passes through the focusing coil, and then the suspension wire 50
The current i1 'returning to the soldering portion 96c flows through c.

Then, each suspension wire 50b,
Over the length of 50c, magnetic fields H2 and H3 are generated in the clockwise direction in the direction in which the current travels, and their combined magnetic field is generated in the center between the suspension wires 50b and 50c in the F and T directions. In the plane including the angle F, an angle θ ′ is substantially the same as the angle θ between the T direction and the straight line connecting the soldering portions 96b and 96c with respect to the F direction.

[0013] Therefore, when the conventional method for supplying power to the coil is performed in the conventional biaxial actuator, the suspension wires 50a, 50b, 50
Since a magnetic field acts on each coil disposed between the coils c and 50d in a direction other than the F direction and the T direction, the magnetic force of a driving unit composed of a focusing coil, a tracking coil, a yoke, and a magnet. Affect the circuit,
Precise movement of the lens holder in the F and T directions is impeded,
A problem arises in that the optical axis of the objective lens is displaced and the information recording surface of the optical disc cannot be accurately reproduced or recorded. When the soldering portions 96a to 96d at arbitrary diagonal positions are a combination of F + and F- or a combination of T + and T-, the above problem occurs.

Further, the printed circuit board 92 has a problem that the printed circuit board 92 is rotated around the screw position when the screw is tightened, since the central portion thereof is merely screwed to the fixing member 90 by the screw 94.

SUMMARY OF THE INVENTION An object of the present invention is to improve the workability when mounting a printed circuit board, facilitate the wiring and soldering and positioning of a conductor on the printed circuit board, and have no effect on the magnetic circuit. An object of the present invention is to provide a biaxial actuator capable of preventing rotation of a printed circuit board.

[0016]

As a first means for solving the above-mentioned problems, a lens holder to which an objective lens is fixed and a lens holder movably supported in two axial directions of a focusing direction and a tracking direction. And, a plurality of elastic support members that conduct electricity, a printed circuit board for fixing an end of the elastic support member, a fixing member to which the printed circuit board is attached and fixed, and a device for driving the lens holder At least a part of the driving unit is disposed on the base member, and the printed circuit board has a plurality of soldering portions for soldering and fixing an end of the elastic support member, and a plurality of soldering portions respectively connected to the soldering portion. And a conductive contact portion, wherein the soldering portion and the conductive contact portion are disposed at point-symmetric positions with respect to a point at a central portion of the printed circuit board, and It is characterized in that it has a feeding portion fed from the conductor the contact portion.

Further, as a second solution, the lens holder is movably supported by four elastic support members, and the soldering portions are disposed at four corners of the printed circuit board.
The conductive contact portion includes two current supply portions for supplying a current for a focusing coil and two current supply portions for supplying a current for a tracking coil, and is provided at a central portion of the printed circuit board. It is assumed that.

Further, as a third solution, one end of the conductor is placed between the conductive contact portion and an edge of the printed circuit board.

Further, as a fourth solution, the soldering portions located at both ends of one side of an imaginary square connecting the soldering portions are provided with two current supplies for supplying current for the focusing coil. Part.

Further, as a fifth solution, the fixing member is provided with a plurality of protrusions, and the printed board is provided with a plurality of holes into which the protrusions are fitted.
The hole is disposed at a point symmetrical position with respect to one point of the central portion.

Further, as a sixth solution, the conductor is a flexible substrate, and the flexible substrate is provided with at least one positioning hole, and the positioning hole is fitted to the projecting portion to thereby form the flexible substrate. Is soldered to the conductive contact portion.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A biaxial actuator 10 according to a first embodiment of the present invention is shown in FIGS.
4 and 5 respectively show a perspective view, a plan view, a side view,
This will be described below with reference to a front view as viewed in the direction S in FIG. 3 and an explanatory diagram for explaining how to solder the terminals of the flexible substrate 40 to the printed circuit board 16.

As shown in FIGS. 1 to 3, the objective lens 1
1 are fixedly provided on both sides of the lens holder 12 in the tracking (T) direction in the figure.
a (12b, 12b) include suspension wires 13a, 13b which are conductive elastic support members arranged in parallel.
One end of (13c, 13d) is held respectively,
2 and 3, relay substrates 30 (31) are fixed to both side walls of the lens holder 12 in the T direction, and respective wire fixing portions 30a, 30b formed on the surface of the relay substrate 30 (31). At (30c, 30d), the suspension wires 13a, 13b (13c, 13d) are soldered (the soldering state is not shown).

Further, each suspension wire 13a-
The other end of 13d is soldered to a printed board 16 mounted on a side opposite to the objective lens 11 side of a fixed member 15 mounted on a base plate 14 as a base member, so that the lens holder 12 is fixed to the fixed member 15 Are supported so as to be movable in two axial directions of a tracking (T) direction and a focusing (F) direction. The base plate 14 is formed of a steel plate.

On the other hand, as shown in FIG.
In the optical pickup chassis, mounting portions 14d, 14d provided on both sides of the base plate 14 in the T direction on the objective lens 11 side are screwed to the mounting surface 22a of the optical pickup chassis 22 by screws 21, 21. 22. Further, support portions 14e and 14f provided on both sides of the other end portion are provided with screw holes 14g and 14h, respectively.
As shown in FIG. 3, screws 23a and 23 are inserted through the optical pickup chassis 22 from below to above.
The other end of the base plate 14 is supported by the leading end of b being engaged with the screw holes 14g and 14h, respectively.

The lens holder 12 has a focusing coil 17 and two tracking coils formed by winding in the direction perpendicular to the winding direction of the focusing coil 17 and adjacent to the focusing coil 17 on the objective lens 11 side. The coils 18, 18 are fixed. In addition,
Since the tracking coils 18 are formed in two by one stroke of the wire for the coil, the number of terminals for supplying power to each coil 18 becomes two. Further, the base plate 14
As shown in FIG. 3, bent pieces 14a and 14b obtained by bending a part of the base plate 14 are integrally formed to form a U-shaped yoke 14c having an open upper portion. Further, magnets 19a and 19b (see FIG. 1) are fixed to the bent pieces 14a and 14b, respectively, so as to be opposite to each other. Further, a top yoke 20 is fixed by an adhesive 24 so as to close an open upper portion of the yoke 14c.

The bent piece 14 to which the magnet 19a is fixed
a is inserted into a hole 12c (see FIG. 2) provided in the lens holder 12, and as shown in FIG.
The bent piece 14b with the fixed 9b is inserted into the hollow core hole of the focusing coil 17 so that the magnet 1
9a and 19b are provided on the yokes 14 so that the tracking coils 18 and 18 and one side of the focusing coil 17 are interposed therebetween.
c is arranged.

As shown in FIG. 3, one terminal 18a of the tracking coils 18, 18 is soldered to a terminal fixing portion 30e which is pattern-connected to the wire fixing portion 30a of the relay board 30 provided on the lens holder 12. (The soldering state is not shown). One terminal 17a of the focus coil 17 is soldered to a terminal fixing portion 30f which is pattern-connected to the wire fixing portion 30b. The other terminal 18b (see FIG. 2) of the tracking coil 18, 18 is connected to the terminal fixing portion 30g which is pattern-connected to the wire fixing portion 30c of the relay substrate 31 (see FIG. 2) which is symmetrical with the relay substrate 30. The other terminal 17b (see FIG. 2) of the focusing coil 17 is soldered to the terminal fixing portion 30h which is pattern-connected to the wire fixing portion 30d.

As a result, the tracking coils 18, 1
8 through the suspension wires 13a and 13c,
Power is supplied to the focusing coil 17 through the suspension wires 13b and 13d, so that the focusing coil 17 and the tracking coils 18, 1
In the driving section including the coil 8, the yoke 14c, and the magnets 19a, 19b, the magnetic field generated in each coil is mutually reciprocal with the magnetic field generated by the magnets 19a, 19b fixed to the yoke 14c and the bent pieces 14a, 14b, respectively. By acting, the lens holder 12 to which each coil is fixed is driven in the T and F directions. Therefore,
The objective lens 11 fixed to the lens holder 12 is driven in two axial directions.

With the above configuration, the laser beam emitted from the light emitting element of the optical pickup (not shown) is focused on the information recording surface of the optical disk via the objective lens 11. Then, the return light from the information recording surface of the optical disc passes through the objective lens 11 again and enters the photodetector of the optical pickup, whereby the information recorded on the information recording surface is read. At that time, the energization of the focusing coil 17 and the tracking coils 18 fixed to the lens holder 12 is appropriately controlled, so that
The focusing and tracking operations of the objective lens 11 are performed.

FIG. 4 is a front view of the suspension wire 13 shown in FIG.
The state where the other ends of a to 13d are soldered to the printed circuit board 16 is shown.

First, the printed circuit board 16 has a substantially rectangular shape whose longitudinal direction is the direction T, and the four corners thereof have through holes 1 through which the suspension wires 13a to 13d can be inserted.
Circular soldering portions 16a to 16d having the centers of 6a 'to 16d' are provided, and the through holes 16a 'to 16d' are provided.
Are arranged in such a manner that the vertical sides of the imaginary rectangle connecting the centers of a in order from a 'to d' are parallel to the direction F in the figure, and the horizontal sides are parallel to the direction T.

Also, from the left in the figure, the point is symmetrical with respect to the intersection of the line connecting the centers of the through holes 16a 'and 16d' and the line connecting the centers of the through holes 16b 'and 16c'. Conductive contact portions 16k, 16m, 16n, and 16p are sequentially arranged on the right side. Similarly, the center of the positioning holes 16e and the positioning long holes 16f, which are the holes, is provided so as to be point-symmetrical.

The printed board 16 has a positioning shaft 1 formed at the center of each of the positioning holes 16e and the positioning long holes 16f so as to protrude from the mounting surface 15a of the fixing member 15.
5b and 15c are fitted to the fixing member 15 by fitting, respectively, and are adhesively fixed to the mounting surface 15a. The positioning slot 16f is formed so as to be able to fit into the positioning shaft 15c more smoothly even if the positions of the positioning shafts 15b and 15c vary within a predetermined tolerance range, and have the same shape as the positioning hole 16e. It may be. Further, in FIG. 4, even when the printed board 16 is rotated by 180 degrees with respect to the center of symmetry, the positioning shafts 15b and 15c can be fitted to the respective centers of the positioning long holes 16f and the positioning holes 16e. Do not have.

The soldering portions 16a to 16d are respectively formed with conductive contact portions 16k, 16m, 16n, and 16p.
They are connected by conductive patterns 16g to 16j.
In order to prevent a short circuit, the soldering portions 16a to 16a
6d, the conductive contact portions 16k, 16m, 16n, and 16p, the positioning hole 16e, and the positioning long hole 16f are covered with the resist (broken lines in the drawing indicate that the resist is below the resist). Due to such connection, even when the printed circuit board 16 is rotated by 180 degrees with respect to the center of symmetry, the soldered portion at the upper left in the drawing (the position 16a before rotation) and the conductive contact at the left end are connected. Also, the lower left soldering portion (position 16b before rotation) and the second conductive contact from the left end are connected, and the upper right soldering portion (position 16c before rotation) and the third conductive contact from the left end. The conductive contact part is connected, and the lower right soldering part (1 before rotation)
The relationship between the 6d position) and the rightmost conductive contact portion is not changed.

On the other hand, the other ends of the suspension wires 13a to 13d are respectively inserted into the through holes 16a 'to 16d' of the soldering portions 16a to 16d, and the other ends of the respective suspension wires are electrically connected by soldering. Connected and fixed. Further, as described above, the suspension wires 13a and 13c are connected to the tracking coils 18,1.
8 and 13b and 13d are connected to both terminals of the focusing coil 17 so that power can be supplied to each coil using the conductive contact portions 16k, 16m, 16n, and 16p as power supply portions.

In the present embodiment, the conductive contacts 16k, 1
6n is one of two current supply units for supplying a current for the tracking coil (FIG. 4).
And T +) and the other current supply unit (T- in FIG. 4).
And the conductive contacts 16m, 16p
Are assigned to one current supply unit (represented by F +) and the other current supply unit (represented by F−) of two current supply units for supplying a current for the focusing coil. Then, as shown in FIG. 5, a flexible substrate 40 which is a conductor is provided in the printed circuit board 16 by positioning holes 40 thereof.
When the positioning shaft 15c of the fixing member 15 is fitted to the position e, the terminals 40a to 40d of the flexible substrate 40 are positioned so as to overlap the conductive contact portions 16k, 16m, 16n, and 16p, respectively. Then, the conductive contact 16
k, 16m, 16n, 16p and terminals 40a to 40d are fixed by soldering, respectively.

In this manner, the biaxial actuator 10 is passed from the drive control circuit (not shown) through the flexible substrate 40.
Is supplied to the drive unit.

As described above, according to the biaxial actuator 10 of the present embodiment, when the printed board 16 is mounted and fixed to the fixing member 15, the printed board 16 has no directionality in the mounting direction. This has the effect of improving workability.

Since the conductive contacts 16k, 16m, 16n, and 16p are provided at the center of the printed board 16, the terminals 40a to 40d of the flexible board 40 can be easily wired. Since the mounting space can be secured, the conductive contact portion 1
6k, 16m, 16n, terminal 40a-4 to 16p
There is an effect that soldering of 0d is easily performed. Further, since the positioning shaft 15c of the fixing member 15 is fitted into the positioning hole 40e provided in the flexible substrate 40, the positioning of the flexible substrate 40 is facilitated.

Further, as shown in FIG. 4, the suspension wires 13b and 13d are arranged so as to be parallel to the tracking (T) direction, and each of the two current supply portions for supplying a current for the focusing coil is provided. Since one current supply unit (represented by F +) and the other current supply unit (represented by F−), the combined magnetic field H5 and H6 generated around the center of each suspension wire when power is supplied to the suspension wires is Since the direction acting on the intermediate portion between the suspension wires 13b and 13d is the H4 direction parallel to the focus (F) direction as shown in the figure, the magnetic field acts in a direction other than the F or T direction, and the lens holder 12 is accurately positioned. It does not affect the magnetic circuit of the drive unit so as to prevent undesired movement.

The suspension wires 13a and 13c are arranged so as to be parallel to the tracking (T) direction, and one of the two current supply units (T +) for supplying a current for the tracking coil. )When,
Since the other current supply unit (represented by T-) is used, it goes without saying that a similar effect can be obtained in each tracking coil.

Further, although not limited to the present embodiment and not shown, for example, the suspension wires 13a and 13b are T + and T-, respectively, and the suspension wires 13c and 1c are
Similar effects can be obtained when 3d is F + and F-, respectively. That is, the suspension wires 13a to 13
The above effect can be obtained if the configuration is such that the ends of one side of the virtual square formed by connecting d in order are F + and F−.

Further, the mounting of the printed circuit board 16 to the fixing member 15 is performed by fitting the positioning shafts 15b and 15c provided on the fixing member 15 with the positioning holes 16e and the positioning long holes 16f provided on the printed circuit board 16. Rotation can be prevented because it can be positioned at three locations.
Even if the printed circuit board 16 is rotated by 180 degrees with respect to the center of symmetry, the positioning hole 16e and the positioning slot 1
Since the positioning shafts 15c and 15b are fitted to the center of 6f, the printed circuit board 16 can be prevented from rotating without directivity.

Next, FIGS. 6A and 6B show a printed circuit board 4 relating to a biaxial actuator according to a second embodiment of the present invention.
1 is an explanatory diagram for explaining No. 1.

In the present embodiment, as shown in FIG. 6, the case where the suspension wires 13a to 13d (the same numbers as in the first embodiment) are arranged so as to be the vertices of a virtual square is used. Yes, suspension wire 13a
Through 13d are respectively inserted through holes 41a 'through 41d.
'Soldering portions 41a to 41d having a center'
Are also located at the vertices of the square.

Then, on the printed circuit board 41, the conductive contact portions 41n, 41p, 41
q, 41r, positioning holes 41e, 4
The centers of 1f and the positioning slots 41g and 41h are point-symmetrical positions, and are also line-symmetrical with respect to straight lines passing through the center of symmetry and parallel to the F and T directions. Also, the conductive patterns 41i, 41j, 41k,
41m is a soldering part 41a and a conductive contact part 4 respectively.
1n, similarly 41b and 41p, 41c and 41q, 41d
And 41r are connected to each other, are point-symmetric with respect to the above-mentioned center of symmetry, and are also line-symmetric with respect to the straight line.

The printed circuit board 41 has positioning shafts 15b, 15 of the fixing member 15 (not shown in FIG. 6) at the centers of the positioning holes 41e and the positioning long holes 41g.
c (the same number as in the first embodiment) is fitted to the fixing member 15 and fitted and fixed to the mounting surface 15a by fitting. The positioning elongated hole 41g is formed so that the positioning shaft 15b and 15c can be smoothly fitted to the positioning shaft 15c even if the positions of the positioning shafts 15b and 15c vary within a predetermined tolerance range. It may be.
In FIG. 6, even if the printed circuit board 41 is rotated by 180 degrees with respect to the center of symmetry, the positioning shafts 15b and 15e
Since c can be fitted, the printed circuit board 41 has no directionality.

Further, when the printed board 41 is rotated by 90 degrees with respect to the center of symmetry, the positioning holes 41f are formed.
And positioning shaft 1 at the center of each positioning slot 41h
5b and 15c are fitted with each other.
Even if rotated by 80 degrees, the printed circuit board 41 has no directionality.

Next, a flexible substrate 42 for supplying power to the printed circuit board 41 through the conductive contact portions 41n, 41p, 41q, 41r will be described.

First, in FIG. 6A, the flexible substrate 4
2 is provided with a U-shaped groove 42f at the end thereof, and two terminals 42a, 42b and 42c, 42d are provided on both sides of the groove.
Is arranged. A positioning hole 42e is provided below the U-shaped groove 42f.

As shown in FIG. 6B, the position of the flexible substrate 42 with respect to the printed circuit board 41 is determined by fitting the positioning hole 42e into the positioning shaft 15c of the fixing member 15, and the conductive contact portions 41n, 41p, 41
q, 41r and terminals 42a-42 of flexible substrate 42
d is soldered and fixed.

By doing so, the printed circuit board 41
Is rotated by 90 degrees or 180 degrees with respect to the center of symmetry, the connection relationship between the position of the soldering portion and the position of the conductive contact portion does not change, and thus has no directionality, so that the suspension wires 13a to 13d are square. The effect that the workability is improved is obtained even if it is arranged at the vertex of. The effects of the first embodiment can be obtained also in the present embodiment.

In this embodiment, the conductive pattern 4
Since 1i, 41j, 41k, and 41m are point-symmetric, even if there is a vibration that occurs in the longitudinal direction of the suspension wires 13a to 13d, the vibration can be absorbed by the elasticity of the printed circuit board 41 itself. When the same force is applied, the longitudinal displacements at the positions of the soldering portions 41a to 41d become the same due to the above-mentioned symmetry, so that vibration can be absorbed uniformly and the lens holder 12 (not shown in FIG. 6) can be accurately adjusted. It does not hinder the movement.

[0055]

As described above, the biaxial actuator according to the present invention has a lens holder to which an objective lens is fixed, and supports the lens holder movably in two axial directions of a focusing direction and a tracking direction; A plurality of elastic support members that conduct electricity, a printed circuit board for fixing an end of the elastic support member, a fixing member to which the printed circuit board is fixed, and a driving unit for driving the lens holder At least a portion is provided on a base member, and on the printed circuit board, a plurality of soldering portions for soldering and fixing an end of the elastic support member, and a plurality of conductive portions respectively connected to the soldering portion. A contact portion, wherein the soldering portion and the conductive contact portion are disposed at point-symmetric positions with respect to a point at a central portion of the printed circuit board; Since the power supply unit fed from the conductor, when securely attached to the printed circuit board to the fixing member, the mounting direction of the printed board does not have a directivity, it is possible to improve the workability.

Further, the lens holder is movably supported by four elastic support members, soldering portions are provided at four corners of the printed circuit board, and conductive contact portions are provided by two current supply portions for supplying current for the focusing coil. And two current supply units for supplying a current for the tracking coil and provided at the center of the printed circuit board, so that the conductor can be easily wired to the printed circuit board.

Further, since one end of the conductor is placed between the conductive contact portion and the edge of the printed circuit board, a space is provided for placing one end of the conductor on the printed circuit board. Can be easily soldered.

Further, since the soldering portions located at both ends of any one side of the virtual rectangle connecting the soldering portions are two current supply portions for supplying a current for the focusing coil, an accurate positioning of the lens holder is achieved. There is no influence on the magnetic circuit of the drive unit that hinders the smooth movement.

Further, the fixing member is provided with a plurality of protrusions, and the printed circuit board is provided with a plurality of holes into which the protrusions are fitted. Since the printed circuit boards are arranged at point symmetrical positions, the printed circuit board can be attached and fixed to the fixing member using the plurality of holes, so that rotation of the printed circuit board can be prevented.

Further, the conductor is a flexible substrate, and the flexible substrate is provided with at least one positioning hole, and the positioning hole is fitted to the projecting portion so that the flexible substrate is soldered to the conductive contact portion. Since it is attached, the positioning of the flexible board with respect to the printed board can be facilitated.

[Brief description of the drawings]

FIG. 1 is a perspective view of a biaxial actuator according to a first embodiment of the present invention.

FIG. 2 is a plan view of the biaxial actuator according to the first embodiment of the present invention.

FIG. 3 is a side view of the biaxial actuator according to the first embodiment of the present invention.

FIG. 4 is a front view of the biaxial actuator according to the first embodiment of the present invention, viewed from the direction S in FIG. 3;

FIG. 5 is an explanatory view for explaining a state of soldering a terminal of a flexible board 40 to a printed board 16 according to the biaxial actuator of the first embodiment of the present invention.

FIG. 6 is an explanatory diagram illustrating a printed circuit board 41 according to a biaxial actuator of a second embodiment of the present invention.

FIG. 7 is a partial perspective view of a conventional biaxial actuator.

FIG. 8 is an explanatory diagram for explaining a power supply state to a focusing coil in a conventional two-axis actuator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Biaxial actuator 11 Objective lens 12 Lens holder 13a to 13d Suspension wire 14 Base plate 14c Yoke 15 Fixing member 16, 41 Printed circuit board 17 Focusing coil 18 Tracking coil 19a, 19b Magnet 40, 42 Flexible substrate

Claims (6)

[Claims] 1. A lens holder to which an objective lens is fixed, a plurality of elastic support members for movably supporting the lens holder in two axial directions of a focusing direction and a tracking direction, and for supplying current, and the elastic support member A printed circuit board for fixing an end of the printed circuit board, a fixing member to which the printed circuit board is attached and fixed, and a part of a driving unit for driving the lens holder are provided at least on a base member, A plurality of soldering portions for soldering and fixing the ends of the elastic support member, and a plurality of conductive contact portions respectively connected to the soldering portions, wherein the soldering portion and the conductive contact portion are provided. Is disposed at a point symmetric position with respect to one point at the center of the printed circuit board,
A biaxial actuator, wherein the conductive contact portion is a power supply portion supplied with power from a conductor. 2. The lens holder is movably supported by four elastic support members, the soldering portions are disposed at four corners of the printed circuit board, and the conductive contact portions are for supplying current for a focusing coil. 2. The biaxial actuator according to claim 1, comprising two current supply units and two current supply units for supplying a current for a tracking coil, and provided at a central portion of the printed circuit board. 3. 3. The biaxial actuator according to claim 2, wherein one end of the conductor is placed between the conductive contact portion and an edge of the printed circuit board. 4. The soldering portion located at either end of any one side of a virtual square connecting the soldering portions is two current supply portions for supplying current for the focusing coil. The two-axis actuator according to claim 2 or 3, wherein 5. The fixing member is provided with a plurality of protrusions, and the printed circuit board is provided with a plurality of holes into which the protrusions are fitted. The two-axis actuator according to any one of claims 1 to 4, wherein the two-axis actuator is disposed at point-symmetric positions. 6. The conductor is a flexible substrate,
6. The flexible substrate according to claim 5, wherein the flexible substrate is provided with at least one positioning hole, and the positioning hole is fitted to the projecting portion to solder the flexible substrate to the conductive contact portion. Axis actuator.