JP3305432B2 - Two-axis actuator and optical disk device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens for reproducing and / or recording information on a disc-shaped information recording medium such as an optical disc used for a CD, MD, LD, etc., in a focus direction and a tracking direction. Move to 2
The present invention relates to a shaft actuator and an optical disk device including the same.

[0002]

2. Description of the Related Art Conventionally, this type of two-axis actuator has, for example, a structure as shown in FIG. In the figure,
The objective lens 101 of the biaxial actuator 100 is mounted on a lens holder 102.

As shown in FIG. 7, focus coils 104 are fixedly mounted on both sides of the lens holder 102, and a pair of tracking coils 105 are adhered to the outer peripheral surface of the focus coils 104 with an adhesive or the like. ing. Power supply flexible substrates (not shown) are soldered to the terminals 104a and 105a of the focus coil 104 and the tracking coil 105.

[0004] The lens holder 102 on which the objective lens 101, the focus coil 104, and the tracking coil 105 are assembled is fixed to a support 110.
Thus, it is movably supported in a focus direction (vertical direction in FIG. 6) and a tracking direction (horizontal direction in FIG. 6).

On the fixed side, a magnet 112 is provided.
The magnet 112 and the focus coil 1
Magnetic interaction with the lens holder 10
2 moves in the direction of the focus coil. Further, the magnetic interaction between the magnet 112 and the tracking coil 105 controls the lens holder 102 to move in the tracking direction.

[0006]

By the way, in such a two-axis actuator 100, the focus coil 10
Since the pair of tracking coils 105 are bonded and attached to the outer peripheral surface of No. 4, a bonding step is required, and there is a problem that the manufacturing cost is increased.

In the bonding, the focus coil 104 is used.
It is difficult to position the tracking coil 105 with respect to, and the assembling workability is inferior. And the tracking coil 1
Variations are likely to occur in the positioning of the position 05, resulting in poor product accuracy. Furthermore, since the tracking coil 105 is attached only with an adhesive, it may be subjected to an external impact or the like.
There is also a problem that the tracking coil 105 is easily dropped from the focus coil 104.

Further, since there are many variations in the positioning of the tracking coil 105, the terminals 104a, 105a of the focus coil 104 and the tracking coil 105 are different.
In addition, the power supply flexible board cannot be automatically connected, and must be manually soldered. For this reason, the connection work efficiency was poor, and the product production efficiency was poor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and can improve the positioning accuracy of a tracking coil, reduce the cost of products, and automate the work of connecting each coil to a flexible substrate. Two-axis actuator and optical disk using the same
It is intended to provide a device .

[0010]

According to the first object of the present invention , a magnet and a magnet yaw are provided on a fixed side.
The objective lens is supported on the moving side.
Lens holder with tracking coil and tracking coil
And a cylindrical bobbin around which a focus coil is wound.
The elastic body, one end of which is supported on the fixed side,
Two-axis actuator movably supporting lens holder
, The magnet and the magnet yoke are adjacent
And the magnet and the yoke face each other.
The objective lens is located on the side opposite to the fixed side of the elastic body.
The pair of torses are provided at the tip of the lens holder, and
The racking coil is on the first side of the bobbin and on both sides
Rolled over each other with the second side of the
Located between the magnet and the yoke,
The magnet and the magnet are provided in the hollow portion of the cylindrical bobbin.
The bobbin is inserted into the bobbin so that the gnet yoke is inserted.
This is achieved by a two-axis actuator inserted into the bin mount .

According to the second aspect of the present invention, the configuration of the first aspect is provided.
In, the bobbin, and a pin for the focus coil terminals to retrieve the terminals of the focus coil, characterized in that a pin for tracking coil terminal taking out terminals of the tracking coils.

[0012] According to the invention of claim 3, claim 1 or
2. In any one of the configurations (2) and (3), a flexible board for supplying power to the focus coil is electrically connected to the focus coil terminal pin, and a flexible board for supplying power to the tracking coil is supplied to the tracking coil terminal pin. The flexible substrate is electrically connected. The above object is achieved by the invention of claim 4.
If there is a magnet, magnet yoke and yo
The object side is supported on the moving side, and the bobbin is
With the attached lens holder, tracking coil and
A cylindrical bobbin around which a focus coil is wound.
The lens is supported by an elastic body whose end is supported on a fixed side.
Has a biaxial actuator that movably supports the holder
In the optical disc device, the magnet and the magnet
The net yoke is adjacent and the magnet and the
The object lens is fixed to the elastic body.
Provided at the tip of the lens holder on the side opposite to the fixed side.
The pair of tracking coils is the first of the bobbins.
Side and the second side on both sides
Wound between the magnet and the yoke
And the hollow portion of the cylindrical bobbin is
So that the slot and the magnet yoke are inserted
The bobbin is inserted into the bobbin mounting portion,
This is achieved by an optical disk device having a cutuator .

According to the fifth aspect of the present invention, the configuration of the fourth aspect is provided.
In, the bobbin, and a pin for the focus coil terminals to retrieve the terminals of the focus coil, characterized in that a pin for tracking coil terminal taking out terminals of the tracking coils. In the invention of claim 6,
According to any one of claims 4 and 5,
A flexible board for supplying power to the focus coil was electrically connected to the pin for the focus coil terminal, and a flexible board for supplying power to the tracking coil was electrically connected to the pin for the tracking coil terminal. It is characterized by the following.

[0014]

According to the above construction, since the focus coil and the tracking coil are wound around one bobbin, a step of bonding the tracking coil to the focus coil is not required.

Further, if a pin for a focus coil terminal and a pin for a tracking coil terminal are protruded from the bobbin and a flexible substrate for power supply is connected to these pins, such a connection operation is automatically performed. It can be carried out.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, since the Examples described below are preferred specific examples of the present invention, various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. The embodiment is not limited to these embodiments unless otherwise stated.

FIG. 1 is a schematic perspective view showing a biaxial actuator according to one embodiment of the present invention. In the figure, a biaxial actuator 1 is a so-called moving coil type actuator, and includes a lens holder 10 as a lens holding unit for holding the objective lens 2 and a lens holder 10.
Assembled body 20 and coil assembled body 2
The lens holder 10 has a support 40 for supporting the lens holder 10 from both sides, and a magnet 50 that exerts a magnetic effect on the focus coil 30 and the tracking coil 31 of the coil assembly 20.

The lens holder 10 is made of, for example, a resin, and has a circular lens mounting hole 11 at its tip as shown in FIG. In this lens mounting hole 11,
An objective lens 2 for guiding a laser beam or the like to an optical disc (not shown) is mounted. Further, a rectangular bobbin mounting hole 15 is formed in most of the lens holder 10, and the coil assembly 20 is mounted in the bobbin mounting hole 15.

The coil assembly 20 has a structure in which a focus coil 30 and a tracking coil 31 are wound around one bobbin 21 formed of a synthetic resin or the like. Specifically, as shown in FIGS.
Has a flange 22 at the top and bottom (up and down in FIG. 2).
A focus coil 30 is wound around a cylindrical coil winding portion 24 provided between these flanges 22 along a horizontal direction in the figure.

Further, on both sides of the front part of the flange 22,
A pair of coil winding grooves 25, 2 formed by diagonally notching
6 are provided in these coil winding grooves 25 and 26.
A pair of tracking coils 31, 31 are wound in a vertical direction in the drawing in a state of being connected in series. Here, the coil winding grooves 25 and 26 are
(See FIGS. 3 and 5). For this reason, the tracking coils 31 are arranged obliquely to the peripheral surface of the focus coil 30.

That is, since the focus coil 30 and the tracking coil 31 are integrally wound around one bobbin 21, a special process of bonding the tracking coil 31 to the focus coil 30 is not required.

Therefore, if the coil assembly 20 applied to the present embodiment is used, the product cost of the biaxial actuator 1 can be reduced. If the tracking coil 31 is wound around the coil winding grooves 25 and 26,
Since the positioning of the tracking coil 31 with respect to the focus coil 30 is automatically performed, the assembling workability is improved.

As a result, there is no variation in the positioning of the tracking coil 31, and the positioning accuracy is improved. Further, since the tracking coil 31 is wound around the bobbin 21, there is no possibility that the tracking coil 31 is easily dropped off due to vibration applied to the apparatus.

Further, the coil winding grooves 25, 26 around which the tracking coils 31, 31 are wound are provided obliquely at positions slightly away from the coil winding portion 24, around which the focus coil 30 is wound (FIG. 3). , See FIG. 5). For this reason, the position where the tracking coils 31 are wound is the end on one side of the bobbin 22, and the winding work of the tracking coils 31, 31 can be easily performed by an automatic machine or the like.

A pair of conductive focus coil terminal pins 35 and a pair of tracking coil terminal pins 36 are protrudingly provided above the bobbin 21 around which the focus coil 30 and the tracking coil 31 are wound. .

More specifically, as shown in FIG.
Are projected, and the pins 35 for these focus coil terminals are provided.
And both terminals 30a of the pulled out focus coil 30
Is entangled. In addition, tracking coil terminal pins 36 are provided in front of both sides of the upper flange 22, and both terminals 31 a of the tracking coil 31 pulled out are entangled with these tracking coil terminal pins 36.

As shown in FIG. 1, flexible power supply substrates 60 and 61 extending from the fixed side are mounted on the surface of the lens holder 10, respectively. And
The focus coil 3 is connected to the focus coil terminal pin 35.
The flexible substrate 60 for supplying power to the coil 0 is soldered, and the flexible substrate 61 for supplying power to the tracking coil 31 is soldered to the tracking coil terminal pins 36.

As described above, the flexible substrates 60 and 61
Are soldered to the terminals 30a, 31a of the coils 30, 31.
Are performed on the pins 35 and 36 that are electrically connected to the terminals 30a and 31a.

That is, since the flexible boards 60 and 61 are soldered to the pins 35 and 36 which are fixed to the bobbin 21 and do not cause positional shift, the soldering can be performed automatically, not manually. it can. Therefore, by automating this soldering, the flexible substrate 6
The efficiency of the connection work between the coils 0, 61 and the terminals 30a, 31a of the coils 30, 31 can be significantly improved, and the production efficiency of the two-axis actuator 1 can be improved.

As shown in FIGS. 1 and 2, such a coil assembly 20 is provided with a magnet insertion hole 23 of a bobbin 21.
The lens holder 10 is fitted into the bobbin mounting hole 15 of the lens holder 10 with the opening of the lens holder facing up and down, and the lens holder 10 is supported by the support 40 from both sides.

The support 40 has a fixed base 41.
And a pair of leaf springs 45, one ends of which are fixed to both ends of the base 41, respectively. The leaf springs 45 move both sides of the lens holder 10 in which the coil assembly 20 is fitted. It is movably pinched. That is, the lens holder 10 is supported in a suspended state, and the lens holder 10 can be moved in the focus direction (the vertical direction in FIG. 1) and the tracking direction (the horizontal direction in FIG. 1) by the action of an external force. I have.

A rectangular magnet 50 fixed similarly to the support body 40 is inserted into the magnet insertion hole 23 of the bobbin 21. The magnet 50, the focus coil 30, and the tracking coil 31
And the magnet yoke 52 and the yoke 5
4 are inserted into the magnet insertion holes 23 of the bobbin 21.

Accordingly, the focus coil 30 wound around the circumference of the magnet 50 in the direction of the longitudinal axis L, the tracking coil 31 wound in a direction substantially intersecting the focus coil 30 spatially, and the magnet 50 ,
A magnetic circuit composed of the magnet yoke 52 and the yoke 54 is configured.

This embodiment is configured as described above.
The operation of the biaxial actuator 1 will be described. When the focus coil 30 is energized via the flexible substrate 60, the focus coil 30 receives a force in the focus direction due to the magnetic interaction between the focus coil 30 and the magnet 50, and the objective lens 2 moves in the focus direction.

Therefore, by controlling the current passing through the flexible substrate 60, the objective lens 2 can be moved by a predetermined amount, and the light irradiated on the optical disk (not shown) can be focused on the disk surface.

On the other hand, when the tracking coil 31 is energized via the flexible substrate 61, the tracking coil 31 receives a force in the tracking direction due to the magnetic interaction between the tracking coil 31 and the magnet 50.
The objective lens 2 moves in the tracking direction. Thus, by controlling the current passed through the flexible substrate 61, the objective lens 2 can be moved by a predetermined amount and the light can be adjusted to a predetermined track of the optical disk.

[0037]

As described above, according to the present invention,
Since the step of bonding the tracking coil to the focus coil can be reduced, the cost of the product can be reduced. Further, since it is not necessary to position the tracking coil with respect to the focus coil, the assembling workability is improved. Furthermore, since there is no variation in the positioning of the tracking coil, the positioning accuracy is improved. Also, since the tracking coil is wound around the bobbin, there is no possibility that the tracking coil will fall off. Furthermore, if a configuration is adopted in which a pin for a focus coil terminal and a pin for a tracking coil terminal are protruded from the bobbin and a flexible substrate for power supply is connected to these pins, such a connection operation can be automated. Thus, the efficiency of the connection work can be improved and the production efficiency can be improved.

[Brief description of the drawings]

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

FIG. 2 is an exploded perspective view showing a lens holder and a coil assembly.

FIG. 3 is a plan view of a bobbin.

FIG. 4 is a front view of the bobbin.

FIG. 5 is a bottom view of the bobbin.

FIG. 6 is a perspective view showing a two-axis actuator according to a conventional example.

FIG. 7 is an exploded perspective view showing a mounting state of each coil to a lens holder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 2-axis actuator 2 Objective lens 21 Bobbin 30 Focus coil 31 Tracking coil 35 Pin for focus coil terminal 36 Pin for tracking coil terminal 50 Magnet 60, 61 Flexible substrate

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-239939 (JP, A) JP-A-64-70910 (JP, A) JP-A-3-280225 (JP, A) 68120 (JP, U) JP-A-2-35326 (JP, U) JP-A 62-158630 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 7/09-7 /Ten

Claims (6)

(57) [Claims] 1. A magnet and a magnet yoke on a fixed side.
And a yoke, supporting the objective lens on the moving side, and a bobbin mounting part.
Lens holder, tracking coil and focus coil
With a cylindrical bobbin wound with an
The lens holder is moved by the supported elastic body
In a biaxial actuator that supports the magnet , the magnet and the magnet yoke are adjacent to each other.
The magnet and the yoke are opposed to each other, and the objective lens is provided on the opposite side of the fixed side of the elastic body.
The pair of tracking coils are provided at a tip of a lens holder, and the pair of tracking coils are on a first side of the bobbin.
Face and the second side on each side
Wound and located between the magnet and the yoke
In the hollow portion of the cylindrical bobbin, the magnet and the
The bobbin is inserted so that the magnet yoke is inserted.
Characterized in that it is inserted into a bobbin mounting part,
Actuator. 2. The bobbin according to claim 1 , wherein a pin for a focus coil terminal for extracting a terminal of the focus coil and a pin for a tracking coil terminal for extracting a terminal of the tracking coil are provided on the bobbin. Axis actuator. 3. A flexible board for supplying power to the focus coil is electrically connected to the focus coil terminal pin, and a flexible board for supplying power to the tracking coil is supplied to the tracking coil terminal pin. The two-axis actuator according to claim 1, wherein the two-axis actuator is electrically connected. 4. A magnet and a magnet yoke on a fixed side.
And a yoke, supporting the objective lens on the moving side, and a bobbin mounting part.
Lens holder, tracking coil and focus coil
With a cylindrical bobbin wound with an
The lens holder is moved by the supported elastic body
Optical disc having biaxially actuable support
In the apparatus, the magnet and the magnet yoke are adjacent to each other.
The magnet and the yoke are opposed to each other, and the objective lens is provided on the opposite side of the fixed side of the elastic body.
The pair of tracking coils are provided at a tip of a lens holder, and the pair of tracking coils are on a first side of the bobbin.
Face and the second side on each side
Wound and located between the magnet and the yoke
In the hollow portion of the cylindrical bobbin, the magnet and the
The bobbin is inserted so that the magnet yoke is inserted.
Characterized in that it is inserted into a bobbin mounting part,
An optical disk device having an actuator. To wherein said bobbin, characterized the focus coil terminal pin to take out the terminals of the focus coil, in that a tracking coil terminal pin to take out the terminals of the tracking coils, serial to claim 4
-Mounted optical disk device. 6. A pin said focus coil terminals, as well as electrically connect the flexible substrate for supplying power to said focus coil, said pin tracking coil terminals, a flexible substrate for supplying power to said tracking coil 6. The optical disk device according to claim 4, wherein the optical disk device is electrically connected.
Place.