JP3522101B2 - Lens actuator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens actuator, and more particularly to a lens actuator suitable for a moving magnet type optical pickup device.

[0002]

2. Description of the Related Art An optical pickup device to which a conventional lens actuator is applied will be described with reference to the drawings.
FIG. 3 is a perspective view showing an optical pickup device to which a conventional lens actuator is applied. As shown in FIG.
The optical pickup device is, for example, a magneto-optical disk (M
O) or the like optical disc (information medium: not shown), which is attached to an optical disc device (not shown) and made of a metal plate that reciprocates, and a carriage 110 housed in the carriage 110 and the objective lens 20. A lens actuator 100 having, for example, an objective lens 20 for condensing laser light, a light emitting / receiving element 120 in which a light emitting element (not shown) such as a semiconductor laser element and a light receiving element for detecting return light are integrated, A holder 130 that holds the light emitting / receiving element 120 and has a circuit board (not shown) that constitutes a high-frequency circuit for driving the light emitting element and the like, and the holder 1
And a cover 140 that covers 30.

Next, a conventional lens actuator will be described with reference to the drawings. FIG. 4 is a perspective view showing a conventional lens actuator, and FIG. 5 is an exploded perspective view showing a main part of the conventional lens actuator. As shown in FIGS. 4 and 5, the actuator base 10 of the lens actuator 100 is formed into a substantially rectangular shape by molding an insulating molding material, and the side walls 11 facing each other and the front surface connecting the side walls 11 are formed. The wall 12 and the rear wall (not shown), the upper surface wall 13 and the lower surface wall (not shown), and the side wall 11 are provided with a plurality of (eg, 2) arranged in parallel with the upper wall 13.
(A total of four each) V-shaped grooves 14, a pair of substantially rectangular flanges 15 parallel to the grooves 14 and extending outward from the side wall 11, and an upper wall 13. And a plurality of (for example, two) holes 16 provided in the.

The objective lens 20 is formed into a substantially disc shape by molding a plastic material or a glass material, for example.

The lens holder 30 is formed into a substantially L-shape by molding a molding material.
An annular lens holding part 31 for holding 0, a substantially rectangular yoke holding part 32 arranged so as to be orthogonal to a downward direction from a part of the annular shape of the lens holding part 31, and the yoke holding part Plural pieces (for example, 2 pieces) arranged in the direction orthogonal to the central axis of the lens holding portion 31 on the opposite side end faces 33 of the portion 32.
And a substantially V-shaped groove 34 (four in total). In addition, in the lens holding portion 31 of the lens holder 30,
An objective lens 20 is provided. In addition, the yoke holding portion 32 of the lens holder 30 and the actuator base 10
The rear surface wall is disposed so as to face the rear surface wall with a predetermined gap.

The first yoke 40 is formed by cutting and bending a metal plate into a substantially U-shape, and has a first side wall 41, a second side wall 42, a first side wall 41 and a first side wall 41, which face each other. A bottom wall 43 connecting the two side walls 42 is provided. The first side wall 41 of the first yoke 40 is fixed to the yoke holding portion 32 of the lens holder 30.

The magnet 50 is formed in a substantially rectangular shape and is arranged on the second side wall 42 of the first yoke 40. The second yoke 60 is formed by cutting a metal plate into a substantially rectangular shape, and has a rectangular hole 61 at the end in the short side direction. Further, the upper end surfaces of the first side wall 41 and the second side wall 42 of the first yoke 40 are inserted into the holes 61 of the second yoke 60, and the second yoke 60 is connected to the first side wall 41 and the second side wall 42. It is arranged in a state of spanning the side wall 42.

The coil portion 70 is formed in a substantially rectangular tubular shape, and has a tubular coil bobbin 71 formed by molding an insulating molding material and a coil (not shown) wound around the outer peripheral surface of the coil bobbin 71. It has and. This coil part 70
Is, for example, on the rear wall of the actuator base 10.
The second side wall 42 provided with the magnet 50 is inserted through the hollow portion of the coil portion 70.

The elastic member 80 is linearly formed of an elastic metal material or molding material. One end 81 is engaged with the groove 34 of the lens holder 30 and the other end 82 is formed. , Is engaged with the groove 14 of the actuator base 10. The elastic member 80 engaged with each of the grooves 34, 14 is made of, for example, an adhesive material.
It is fixed to 14. In this way, the four elastic members 80 form the lens holder 30 and the actuator base 1.
0 and 0 are arranged at predetermined intervals so as to bridge each other.

The lens actuator 1 having the above structure
Reference numeral 00 denotes the actuator base 10 fixed to the carriage 110, and the lens holder 30 is movably supported by the elastic member 80. That is, the lens holder 30 that is engaged and fixed to one end 81 of the elastic member 80 with the actuator base 10 as a support point moves in the focus direction and the tracking direction with respect to the information medium (not shown). It is arranged so that it can be. The movement of the lens holder 30 in the focus direction and the tracking direction is performed by passing a current through the coil of the coil unit 70 arranged between the lens holder 30 and the actuator base 10 so that the magnet 50 moves in the focus direction and The magnet 50 is moved in the tracking direction, and the movement of the magnet 50 moves the lens holder 30 via the first and second yokes 40 and 60 integrated with the magnet 50.

Next, the lens actuator 100 described above.
The assembly will be described. First, the objective lens 20 is engaged and fixed to the lens holding portion 31 of the lens holder 30. Next, the magnet 50 is disposed on the inner wall of the second side wall 42 of the first yoke 40, and the first yoke 4 on which the magnet 50 is disposed.
The outer wall of the first side wall 41 of 0 is arranged so as to overlap the yoke holding portion 32 of the lens holder 30. Next, the coil portion 70 is fixed to the rear wall of the actuator base 10.

Next, the magnet 50 is placed in the hollow portion of the coil portion 70.
The second yoke 60 is connected to the first side wall 41 and the second side wall 4 of the first yoke 40 while penetrating through the second side wall 42 fixed to the first yoke 40.
It is arranged so as to connect the two. Next, the objective lens 20
One of the grooves 34 of the lens holder 30 to which is fixed and one groove 14 of the actuator base 10 are on the same plane that is substantially parallel to the ground and on a jig ( (Not shown) or the like. In this state,
The elastic member 80 is arranged in the grooves 34, 14 so as to bridge the both grooves 34, 14, and then the elastic member 80 arranged in the grooves 34, 14 is formed with, for example, an adhesive material. Stick to.

Next, the elastic member 80 is inserted into one of the grooves 34 and 14.
The lens holder 30 and the actuator base 10 to which is fixed are reversed by about 180 degrees and the other groove 3
4 and 14 are placed on the upper surface side and held by a jig (not shown) or the like as described above. In this state, the other groove 34, 14
The elastic member 80 is arranged in the grooves 34 and 14 so as to be bridged over it, and then the elastic member 80 arranged in the grooves 34 and 14 is fixed to the grooves 34 and 14 with an adhesive or the like. This completes the assembly of the lens actuator 100.

[0014]

However, in the conventional lens actuator, the V-shaped groove 34 of the lens holder 30 and the V-shaped groove 1 of the actuator base 10 are used.
Although the linear elastic member 80 is engaged and fixed to the elastic member 4, the elastic member 80 is arranged in a state where the side end surface 33 of the lens holder 30 and the side wall 11 of the actuator base 10 are arranged perpendicular to the ground. When trying to assemble 80 into the respective grooves 34 and 14, the elastic member 80 falls out from the grooves 34 and 14 as it is.

Therefore, as in the above-described assembly procedure, the elastic member 80 is arranged with the side end surface 33 of the lens holder 30 and the side wall 11 of the actuator base 10 arranged substantially parallel to the ground. Are assembled in the respective one of the grooves 34, 14 and engaged and fixed respectively, and with the elastic member 80 fixed, the lens holder 30
And the actuator base 10 are inverted by about 180 degrees, and another elastic member 80 is provided in each of the other grooves 34 and 14.
It requires a man-hour for engaging and fixing the. As a result, the number of working steps for disposing the elastic member 80 on the actuator base 10 and the lens holder 30 increases,
There is a problem of high cost.

Therefore, the lens actuator of the present invention solves the above-mentioned problems, and its purpose is to:
(EN) Provided is an inexpensive lens actuator that requires a small number of work steps during assembly.

[0017]

A lens actuator according to the present invention has an objective lens which is driven in a focus direction and a tracking direction with respect to an information medium, holds the objective lens, and has grooves on both side end faces. A lens holder,
An actuator base that is disposed at a predetermined distance from the lens holder and has grooves on both side walls, and a pair of engaging portions that are hung between the groove of the lens holder and the groove of the actuator base. and an elastic member having a connecting portion for connecting the pair of engaging portions, said by the pair of engaging portions of the elastic member, and held as pinching and said actuator base and the lens holder Is.

Further, the lens actuator of the present invention is
The elastic member is formed of a wire made of a linear metal material ,
The connecting portion of the elastic member is on the side opposite to the lens holder.
Located on the front wall side of the actuator base located at
did. Further, in the lens actuator of the present invention, the elastic member is provided with a holding portion protruding from the outer periphery of the actuator base . Further, the lens actuator of the present invention
The holding member of the elastic member is the lens holder.
Front side of the actuator base located on the side opposite to the
It was placed on the wall side. Further, the lens actuator of the present invention
Is installed on the lens holder and the actuator base.
The carved groove was formed in a substantially V shape.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the lens actuator of the present invention will be described below with reference to the drawings. Figure 1
FIG. 4 is a perspective view showing a lens actuator of the present invention. The same components as those of the conventional lens actuator are designated by the same reference numerals.

As shown in FIG. 1, the actuator base 10 is formed by molding an insulating molding material into a substantially rectangular shape, and has side walls 11 facing each other, a front wall 12 connecting the side walls 11 and a rear wall. Provided on the face wall (not shown), the upper face wall 13, the lower face wall (not shown), and the side face wall 11, the upper face wall 1
A plurality of substantially V-shaped grooves 14 (for example, two in total, four in total) arranged in parallel with the groove 3 and the groove 14 which is parallel to the groove 14 and extends outward from the side wall 11. And a pair of substantially rectangular flange portions 15 and a plurality of (eg, 2
Individual holes 16).

The objective lens 20 is formed into a substantially disc shape by molding a plastic material or a glass material, for example.

The lens holder 30 is formed into a substantially L shape by molding an insulating molding material, and has an annular lens holding portion 31 for holding the objective lens 20.
A substantially rectangular yoke holding portion 32 is provided so as to be orthogonal to the downward direction from a part of an annular shape of the lens holding portion 31, and the lens holding portion 3 is provided on the side end surfaces 33 of the yoke holding portion 32 which face each other.
A plurality of (e.g., two, four in total) substantially V-shaped grooves 34 arranged in a direction orthogonal to the central axis of the one. The objective lens 20 is arranged in the lens holding portion 31 of the lens holder 30. Further, the yoke holding portion 32 of the lens holder 30 and the rear surface wall of the actuator base 10 are arranged so as to face each other with a predetermined gap.

The first yoke 40 is formed into a substantially U-shape by cutting and bending a metal plate, and the first side wall 41, the second side wall 42, the first side wall 41 and the first side wall 41 facing each other are formed. A bottom wall 43 connecting the two side walls 42 is provided. The first side wall 41 of the first yoke 40 is arranged on the yoke holding portion 32 of the lens holder 30.

The magnet 50 is formed in a substantially rectangular shape and is arranged on the second side wall 42 of the first yoke 40. The second yoke 60 is formed by cutting a metal plate into a substantially rectangular shape, and has a rectangular hole 61 at the end in the short side direction. Further, the upper end surfaces of the first side wall 41 and the second side wall 42 of the first yoke 40 are inserted into the holes 61 of the second yoke 60, and the second yoke 60 is connected to the first side wall 41 and the second side wall 42. It is arranged in a state of spanning the side wall 42.

The coil portion 70 is formed in a substantially rectangular tubular shape, and has a tubular coil bobbin 71 formed by processing an insulating molding material, and a coil (not shown) arranged on the outer peripheral surface of the coil bobbin 71. It has and. This coil part 70
Is arranged on the rear wall of the actuator base 10, and the second side wall 42 to which the magnet 50 is fixed is arranged in the hollow portion of the coil portion 70.

The elastic member 90 has elasticity and is formed into a substantially U shape by bending or welding a wire-shaped metal material. Then, a substantially arc-shaped holding portion 91 formed in a substantially U-shaped substantially central portion, connecting portions 92 and 92 extending outward from both end portions of the holding portion 91, and the connecting portion 92. A pair of engaging portions 93, 93 that are substantially right-angled from the end portions of the first and second portions 92, 92 and are bent and extended so that the dimension between the one end portions 93a, 93a is narrowed inward. I have it. That is, the dimension between the end portions 93a, 93a of the pair of engaging portions 93, 93 is determined by the lens holder 30.
It is provided so as to be slightly smaller than the dimension between the grooves 34, 34. Further, one ends 93 a, 93 a of the engaging parts 93, 93 are engaged with the groove 34 of the lens holder 30, and the other ends 93 b, 93 b are engaged with the groove 14 of the actuator base 10. . Then, the engaging portions 93 of the elastic member 90 engaged with the respective grooves 34, 14,
93 are grooves 34, 1 with an adhesive (not shown) or the like.
It is fixed to 4.

Although not shown in the drawings, the tips of the engaging portions 93, 93 are, for example, guides inclined toward the outside (outside) for facilitating the insertion into the grooves 34, 14. May be provided, and the inserted engaging portions 93, 93
It is also possible to provide a retaining portion such as a convex portion for preventing the groove from coming off from the grooves 34 and 14. In addition, the connection portion 92,
92 and the engaging portions 93, 93 may be connected and integrated by welding.

At this time, the connecting portions 92, 9 of the elastic member 90 are
2 is arranged in contact with the front wall 12 of the actuator base 10. In this way, the engaging portions 93, 93 of the elastic member 90 are arranged so as to bridge the lens holder 30 and the actuator base 10 at a predetermined interval.

The operation of the lens actuator 150 of the present invention is the same as the operation of the conventional lens actuator 100, and a description thereof will be omitted.

Next, the lens actuator 15 of the present invention.
The assembly of 0 will be described. Since this assembly is almost the same as the assembly of the conventional lens actuator 100, detailed description thereof will be omitted. So here,
Assembly of the elastic member 90 into the lens holder 30 and the actuator base 10 will be described. This installation is performed so that the yoke holding portion 32 of the lens holder 30 to which the objective lens 20 is fixed and the front wall 12 of the actuator base 10 are parallel to each other and perpendicular to the ground. And the actuator base 10 are fixed to a jig (not shown) or the like.

A holding portion 91 of a substantially U-shaped elastic member 90 which is engaged with the groove 34 of the lens holder 30 and the groove 14 of the actuator base 10 in a state of being fixed to this jig or the like is, for example, The pair of engaging portions 93, 93 of the elastic member 90 are simultaneously engaged with the respective grooves 34, 34, 14, 14 from the front wall 12 side of the actuator base 10 by holding them with a hand or the like. In this engaged state, the elastic member 90 is substantially U-shaped, and the dimension between the one end portions 93a, 93a of the pair of engaging portions 93, 93 is the lens holder 30.
Since the size is set to be slightly smaller than the dimension between the grooves 34, 34 of the engaging portions 93, 93, the engaging portions 93, 93
The pins 4 and 14 are sandwiched and held in a state of being elastically contacted with each other, so that the elastic member 90 does not fall out of the respective grooves 34, 34, 14, 14. Next, the pair of engaging portions 9 engaged with the respective grooves 34, 34, 14, 14.
3, 93 are fixed by an adhesive or the like. with this,
The assembly of the lens actuator 150 is completed.

Next, a second embodiment of the elastic member relating to the lens actuator of the present invention will be described with reference to the drawings. FIG. 2 is a perspective view showing a second embodiment of the elastic member relating to the lens actuator of the present invention.
The elastic member 94 has elasticity, and is formed by bending and welding a wire-shaped metal material into a two-tiered, generally U-shape. The elastic member 94 has a substantially arcuate holding portion 95 formed in a substantially central portion of a substantially U-shape, and the first connecting portion 9 extending outward from both ends of the holding portion 95.
6, 96, a pair of first engaging portions 97, 97 extending from one end portion of the first connecting portions 96, 96 in a substantially right-angled shape in two directions, and a pair of second connecting portions 98. , 98 and the first connecting portions 96, 9 from the ends of the second connecting portions 98, 98.
6 is provided with a pair of second engaging portions 99, 99 extending in parallel. Further, the pair of first engaging portions 97, 97 and the second engaging portions 99, 99 are formed such that one end portion (tip portion) of each of them is slightly narrowed inward. There is.

Assembling of the elastic member 94 having the above-described structure into the lens holder 30 and the actuator base 10 is substantially the same as the assembling of the elastic member 90 of the first embodiment described above. The elastic member 94 has a total of four since the first engaging portions 97, 97 and the second engaging portions 99, 99 are connected and integrated by the second connecting portions 98, 98. First and second engaging portions 97, 9
7, 99, 99 can be incorporated into the respective grooves 34, 14 in one simultaneous working step.

In the elastic members of the above-described first and second embodiments, the substantially arcuate holding portion is provided at the connecting portion of the elastic member, but the holding portion is not limited to this. You don't have to. In the elastic members of the first and second embodiments described above, the elastic member is formed in a substantially U shape, but the shape is not limited to the substantially U shape, and for example, a substantially U shape lens Holder 3
It suffices if the engaging portions are connected so as to sandwich 0 and the actuator base 10.

[0035]

The lens actuator of the present invention comprises an objective lens which is driven in the focus direction and the tracking direction with respect to the information medium, a lens holder which holds the objective lens and has grooves on both side end surfaces. An actuator base that is disposed at a predetermined distance from the lens holder and has grooves on both side walls, a pair of engaging portions that are bridged between the groove of the lens holder and the groove of the actuator base, and the pair of engaging portions. Since the elastic member having the connecting portion for connecting the engaging portion is provided, it is possible to reduce the man-hours for assembling the elastic member into the lens holder and the actuator base, and to provide an inexpensive lens actuator. Produce an effect.

The lens actuator of the present invention is
Since the elastic member is a wire made of a linear metal material, the material cost is low, and the elastic member can be easily processed at low cost.

The lens actuator of the present invention is
Since the elastic member is provided with the holding portion, when the elastic member is incorporated into the lens holder 30 and the actuator base 10, the holding portion can be held by a hand or the like, which facilitates the assembling work.

[Brief description of drawings]

FIG. 1 is a perspective view showing a lens actuator of the present invention.

FIG. 2 is a perspective view showing a second embodiment of an elastic member relating to the lens actuator of the present invention.

FIG. 3 is a perspective view showing an optical pickup device to which a conventional lens actuator is applied.

FIG. 4 is a perspective view showing a conventional lens actuator.

FIG. 5 is an exploded perspective view showing a main part of a conventional lens actuator.

[Explanation of symbols]

10 Actuator base 11 Side wall 14 groove 20 Objective lens 30 lens holder 33 side end face 34 groove 90,94 Elastic member 93, 97, 99 Engagement part 100, 150 lens actuator

Claims (5)

(57) [Claims] 1. An objective lens that is driven in a focus direction and a tracking direction with respect to an information medium, a lens holder that holds the objective lens and has grooves on both side end surfaces, and a predetermined distance from the lens holder. An actuator base having grooves on both side walls, a pair of engaging portions that are bridged between the groove of the lens holder and the groove of the actuator base, and the pair of engaging portions. and an elastic member having a connecting portion connecting the pair of by the engaging portion, the lens actuator is characterized in that holding such pinching and said actuator base and the lens holder of the elastic member. 2. The elastic member is formed of a wire made of a linear metal material, and the connecting portion of the elastic member is formed of the wire.
The actuator base located on the opposite side of the holder
The lens actuator according to claim 1, wherein the lens actuator is arranged on a front wall side of the lens. 3. The actuator includes the elastic member.
The lens actuator according to claim 1 , further comprising a holding portion protruding from the outer periphery of the base . 4. The holding portion of the elastic member is the lens.
Actuator base located on the side opposite the holder
It is arranged on the front wall side of the.
Lens actuator. 5. The lens holder and the actuator
The groove provided on the base is formed in a substantially V shape.
The lens lens according to any one of claims 1 to 4,
Quutator.