JPH0887764A - Objective lens actuator - Google Patents

Abstract

PURPOSE: To reduce the number of parts and to facilitate soldering processing and assemblage. CONSTITUTION: A coil 6 is wound around a coil frame 5 in the biaxial directions, and leader lines 6c of the beginning of winding of this coil and the end of the winding are wound around line processing grooves 5e and 5f respectively, and the soldering processing is performed on their edges 6d. A terminal pattern corresponding to this soldering processing part and a flexible printed circuit board 12 having a through hole processing part 12e of continuity to this terminal pattern 12b are brought into contact with each other, and are soldered up together so that each coil and a printed circuit pattern 12a become continuity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens actuator for recording on or reproducing from an optically disk-shaped recording / reproducing medium.

[0002]

2. Description of the Related Art In recent years, an apparatus (hereinafter referred to as an optical disk apparatus) for recording and reproducing information using a disc-shaped optical recording / reproducing medium (hereinafter referred to as a disk) has advantages of large capacity and high speed. It is recognized and widely used for voice, image and data recording. Among the parts incorporated in this optical disk device, the objective lens actuator is positioned as an important mechanical part that affects the recording / reproducing performance.

A conventional objective lens actuator will be described below with reference to the drawings. FIG. 5 is an external perspective view of an objective lens actuator of a conventional example, FIG. 6 is an exploded perspective view of the objective lens actuator, and FIG. 7 is a cross-sectional view of essential parts showing a mounting portion of the electromagnetic coil. This example shows an objective lens actuator in which four suspension wires are used to hold a lens holder, which is now widely used.

The lens holder 32 shown in FIGS.
The objective lens 1 is adhered and fixed to the upper surface of the drawing, and the balance weight 34 is adhered and fixed to the lower surface thereof. Is magnetized in the N-S direction, and two magnets 3 are fixedly bonded. A support holder 37 is fixed to one end on the base 40, and a soldering substrate 38 for fixing the other end of the suspension wire 39 by soldering is fixed to the support holder 37 by adhesion.
The suspension wire 39 is obtained by cutting a linear spring material into a predetermined length, and has a small hole 43 of the soldering substrate 38 made of a printed board, a small hole 44 of the support holder 37, and a small hole 45 of the holder 32. Penetrating through, four pieces are arranged in parallel, and both ends thereof are connected to the soldering board 35 fixed to the lens holder 32 and the soldering board 38 fixed to the support holder 37 by soldering portions 41 and 42 in the figure. Soldered.

An electromagnetic coil 36 for facing the magnet 3 and electromagnetically driving the magnet 3 is also fixed to the base 40 at a predetermined position via a printed board 47, and the details thereof are shown on a winding frame 36a in FIG. Two types of windings are made: a winding wire 36b having an arrow X1-X2 as an axis and a winding wire 36c having an arrow Y1-Y2 as an axis. Metal pin 3 planted on 36a
It is wound around the base 36e of 6d and soldered 36f
Will be done. Next, the pins 36d of the winding frame 36a are inserted into the four holes 47a of the printed board 47, fixed by soldering 47c, and electrically connected to the print pattern. The mounting hole 47b of the printed circuit board 47 is formed in the base 4
No. 0 screw hole 40a is screwed through a spacer 48, and is drawn out by a lead wire (not shown) soldered to the print pattern and connected to an electric circuit (not shown). And opening 46 from the top of this assembly
The cover 46 having a is attached to the base 40 by the hooking portion 46b.

The operation of the conventional objective lens actuator constructed as above will be described below.
Both ends of the suspension wire 39 are fixed, and the lens holder 32 side is cantilevered with respect to the support holder 37, and the lens holder 32 is supported by the arrow X1-X2 and the arrow Y1.
It is possible to translate in the -Y2 direction.
When a current was applied to two types of windings, one having the arrow X1-X2 as the axis and the other having the arrow Y1-Y2 as the axis, the electromagnetic coil 36 was magnetized in the N-S direction so as to be opposed to and separated from it. Magnet 3
An arrow X is applied to each magnet 3 by the electromagnetic force generated between
A driving force in the 1-X2, Y1-Y2 directions is generated to move the lens holder 32, and thus the objective lens 1 fixed thereto.
Are driven in the directions of arrows X1-X2 and Y1-Y2.

As a result, it is possible to move the focal position of the laser beam focused on the disc (not shown) above the objective lens through the objective lens 1, such as surface wobbling in the disc surface direction and eccentricity in the radial direction. The recording or reproducing operation of the information signal is performed following the.

[0008]

However, in the structure of the above-mentioned conventional example, the windings 36b and 36c of the electromagnetic coil 36 are formed.
The lead wire of the pin 36 of the coil winding frame 36a
After being wound around d and soldered, the pins 36d are further passed through the holes 47a of the printed circuit board 47 and soldered,
Further, the printed circuit board 47 must be fixed to the base 40, and lead wires must be drawn out by soldering from the base 40, so that there are many soldering points, and there is a problem that solder defects are likely to occur.

Further, since the coil winding frame 36a is once soldered to the printed circuit board 47 and this printed circuit board 47 is attached to the base 40, there are many places where a positional error occurs, and a final positioning operation is required. There was a problem.

Further, since the number of parts is large, the work of winding the lead wire around the pin 36d and the hole 47 of the printed circuit board 47 are performed.
There is also a problem that the number of work steps is large, such as the work of passing the pin 36d of the coil frame 36a through a is troublesome, and the production cost is high.

The present invention solves the above-mentioned conventional problems. It has few soldering points, is less likely to cause soldering defects, has a small number of parts, is easy to position, and is easy to assemble, and is excellent in productivity. It is an object to provide an objective lens actuator.

[0012]

In order to achieve the above object, the objective lens actuator of the present invention comprises a winding portion for winding coils having different biaxial directions in two layers, and the winding portion. And a plurality of wire processing grooves for covering the inside of the coil for winding the lead wire at the winding start and the winding end of the coil, and the wire processing groove in a part of the wire processing groove. It is a configuration including a coil frame having a solder treatment portion provided on the lead wire wound around the solder wire, and the solder treatment portion may be on an end face of the covering portion or on a flat portion of the covering portion. May be.

Further, the depth of the wire treatment groove can be partially reduced in the solder treatment portion, and when a synthetic resin material is used for the coil frame, heat resistance above the solder melting temperature is required to withstand soldering. It is a structure formed of a material having. Then, a flexible printed circuit board having a corresponding conductive foil is brought into contact with and soldered to the soldering portion.

In order to achieve the above-mentioned other objects, a lens holding member for holding an objective lens, a plurality of linear spring members for supporting the lens holding member, and a fixing member for fixing the linear spring members. And 2 coils with different 2 axis directions
A coil frame connected to a winding part wound around the layer and having a positioning fixing part for the fixing member, wherein a pair of magnets are fixed to the lens holding member by adhesion or molding. Can be used. The coil frame can have a protrusion or an extension for locking the lens holding member, and the coil frame having the extension, the frame-shaped fixing member, and the lens holding unit form a substantially box-shaped structure. be able to.

[0015]

According to the objective lens actuator of the present invention having the above-described structure, the leading and trailing ends of the coil wound around the winding portion are wound around the wire treatment groove of the covering portion of the coil frame to form the wire treatment groove. It is possible to carry out soldering at a part, for example, at the soldering portion at the end portion thereof, and a flexible printed circuit board having a conductive foil corresponding to this soldering portion can be contacted and soldered.

The solder treatment portion may be present not only on the end face of the coating portion but also on the flat portion of the coating portion, and according to the structure in which the depth of the wire treatment groove is partially reduced in the solder treatment portion, soldering is performed. Since the part rises on the surface, the reliability of soldering increases, and when forming the coil frame with a synthetic resin material, if a material with heat resistance above the solder melting temperature is used, the shape will collapse due to soldering There is no such thing.

Further, according to the structure for other purposes described above, the lens holding member for holding the objective lens is supported by the plurality of linear spring members, and the coil is attached to the fixing member for fixing the linear spring members. The frame is easily positioned by the positioning and fixing portion, and acts so that accumulation of mounting errors does not occur.

Further, the coil frame can be locked by the projection or the expansion so that the lens holding member does not excessively swing, and the coil frame having the expansion, the frame-shaped fixing member, and the lens holding part are provided. It becomes a box-like shape, and acts to prevent dust and the like from entering the interior surrounded by these parts.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is an external perspective view of an objective lens actuator according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the objective lens actuator, FIG. 3 is an enlarged perspective view of a coil frame, and FIG. 4 is an electrical connection to the coil frame. It is an assembly drawing showing a method. In FIG. 1 and FIG. 2, a lens holder 2 which is a lens holding member made of synthetic resin has an objective lens 1 adhered and fixed on the upper surface of the drawing and an optical plate 4 on the lower surface thereof, and has wire diameters on the protrusions 2a on both side surfaces. The tip of the suspension wire 8 which is a linear spring member of phosphor bronze or stainless steel of about 100 microns is molded and fixed by molding.
Two magnets 3 which are magnetized in the NS direction as shown in the figure are fixed to the protruding portion 2a and the other both side surfaces at positions of 90 degrees by adhesion or molding. The other end of the suspension wire 8 is molded and fixed to one side wall 10a on a frame-shaped housing 10 which is a fixing member formed of synthetic resin at four fixing points 8a to 8d by molding. And the hole 11 for attachment is provided suitably.

The coil frame 5 made of synthetic resin is provided with a winding portion 5a in the center, which is connected to both upper ends thereof, and a covering portion 5b having a protrusion 5c at one end, and further on both outer sides thereof. Has two wire winding treatment grooves 5e and 5f, and further has positioning fixed holes 5g on both bottom surfaces for firmly fitting and fixing the positioning fixing pins 10b protruding at the four corners of the housing 10. . In the winding portion 5a, the electromagnetic coil 6 is wound by winding a winding 6b having an arrow X1-X2 as an axis on a winding 6a having an arrow Y1-Y2 as an axis. The lead wire 6c at the beginning and end of each winding is wound around the wire processing grooves 5e and 5f several times,
The outer edge portion 6d of each wound wire is fixed by soldering. The flexible printed circuit board 12 to be brought into contact with this portion is printed with a copper foil printed pattern 12
a is formed and the terminal thereof is a terminal pattern 12b having an expanded area, and if necessary, a through hole processing portion 12e electrically connected to the terminal pattern portion 12b is provided in the recess 12d of the cross section 12c.

As can be seen from FIG. 1, the upper surface of the objective lens actuator occupies a large area because of the lens holder 2, the electromagnetic coil 6 and the coil frame 5 wound around it.
As shown in FIG. 3, if the coil frame 5 is provided with the extension portion 5h, the upper surface of the objective lens actuator is almost covered, and it is difficult for dust or the like to enter the inside without a special cover. Braking material holding frame 7 made of transparent synthetic resin
Has at both ends positioning fixing holes 7a for firmly fitting and fixing to positioning fixing pins 10c projecting at two lower portions of the housing 10, and two partition walls 7b are provided inside thereof.
have.

The assembling method of the objective lens actuator of the present embodiment having the above structure will be described below. The other end of the suspension wire 8 molded and fixed to the protrusions 2a on both sides of the lens holder 2 is fixed to one side wall 10a of the housing 10 by mold, and the lens holder 2 is cantilevered by the four suspension wires 8. There is. The two coil frames 5 around which the coils 6 are wound are symmetrically arranged with respect to the objective lens 1 from above the housing 10, and the positioning fixing pins 10b of the housing 10 are press-fitted into the positioning fixed holes 5g.

Each lead wire 6c at the beginning and end of each winding 6a of the coil frame 5 is soldered and fixed to the edge portion 6d at which the lead wire 6c is wound several times around the wire treatment grooves 5e and 5f. The flexible printed circuit board 12 is brought into contact with this portion as shown in the figure, and the terminal pattern 12b of the terminal of the printed pattern 12a, the through hole processing portion 12e, and the edge portion 6d are soldered, so that the other end A signal current is applied to the electromagnetic coil 6 by being electrically connected to the print pattern 12a of the flexible printed board 12 connected to an electric circuit (not shown).
Therefore, when the coil frame 5 is formed of synthetic resin, it is necessary to use a synthetic resin material having heat resistance equal to or higher than the solder melting temperature. In addition, as a partial change of the reel 5, FIG.
In the cross-sectional view of the line-treated groove 5e or 5f shown in FIG. 4 (a), the shallow groove portion 5 in which the bottom of the groove is particularly shallow at the end is shown.
By making i, the wound lead wire 6c
The surface of is slightly protruding from the coil frame 5. Then, since the flexible printed circuit board 12 is thin, sufficient electrical connection can be made by the raised solder 12f without providing the through hole processing portion 12e.

Here, the wire treatment groove 5 is provided at the end of the coil frame 5.
Although an example in which e or 5f is made shallow is shown, a protrusion is provided at the bottom of the line processing groove 5e or 5f on the upper surface 5d in FIG. 4 (a) so that the lead line partially protrudes from the surface or slightly. Flexible printed circuit board 12
May be applied in parallel to the covering portion 5b from above for soldering. Although the flexible printed circuit board 12 is illustrated as being soldered at the end, it may be soldered by forming a hole in the flexible printed circuit board 12.

Next, the braking material holding frame 7 is press-fitted into the positioning fixed hole 7a from below in alignment with the positioning fixing pin 10c of the housing 10. When the braking material holding frame 7 and the partition wall 7b are fixed, the housing 10
Since the inner wall 10d and the covering portion 5b of the coil frame 5 form a space that encloses two suspension wires 8 from each of the five directions, the space has a liquid state, for example, an ultraviolet curable property containing silicon as a main component. Optimal braking effect when a suspension material 8 vibrates while supporting the lens holder 2 by injecting a braking material 9 (not shown) and irradiating ultraviolet rays from the lower surface of the transparent braking material holding frame 7 to cause gelation. To have. The damping material may be a viscoelastic body such as rubber or elastomer in addition to the gel body.

Next, the operation of the objective lens actuator of the embodiment thus constructed will be described. The electromagnetic coil 6 having the arrows X1-X2 as its axes and the arrows Y1-Y.
When current is passed through the flexible printed circuit board 12 through the two-axis windings and the two types of windings 6a and 6b,
A driving force in the directions of arrows X1-X2 and Y1-Y2 is generated in the magnets 3 fixed to the lens holder 2 by the electromagnetic force generated between the magnets 3 facing each other and magnetized in the NS direction. Then, the lens holder 2 cantilevered by the suspension wire 8 and, accordingly, the objective lens 1 fixed thereto is driven in the directions of arrows X1-X2 and Y1-Y2. At this time, the braking member 9 supports the lens holder 2 and gives an optimum braking effect to the vibrating suspension wire 8.

This makes it possible to move the focus position of the laser light focused on the disc (not shown) located above the objective lens through the objective lens 1, and the surface wobbling and the radius in the plane direction of the disc can be moved. The recording and reproducing operation of the information signal is performed following the eccentricity of the direction.

The housing 10 and the coil frame 5 or the braking material holding frame 7 may be fixed to each other by replacing the positioning fixing pin and the positioning fixed hole, which are opposed to each other, instead of the illustrated method. The position regulating members may be provided to each other and then fixed by adhesion or ultrasonic welding.
Although not shown, a cover corresponding to the cover 46 of the conventional example shown in FIG. 6 may be used if necessary, but a considerable area is covered by the covering portion 5b and the protrusion 5c of the coil frame 5, and By providing the expanded portion 5h, the covered area is further increased, and it is not always necessary to use the cover as in the conventional example.

Further, the protrusion 5c or the extension 5h is
Not only the role as a cover, but also the action of limiting the range of movement of the lens holder 2 when a strong current flows to the electromagnetic coil 6 due to strong vibration or acceleration from the outside or for some reason to cause the lens holder 2 to largely shake. Also brings.

It should be noted that each part of each of the above-mentioned embodiments may be carried out independently, or part of each embodiment may be combined and carried out. Further, it goes without saying that it may be implemented by adding a conventionally known example.

[0031]

As described above, according to the objective lens actuator of the present invention, the winding portion of the coil of the winding portion is connected to the winding portion of the coil frame and covers the inside thereof. Providing a plurality of wire treatment grooves for winding the lead wire, soldering the lead wire wound in a part of the wire treatment groove, and abutting a flexible printed board having a conductive foil corresponding to the solder treatment portion. Since it is configured to be soldered, the number of soldering points is reduced and soldering defects are reduced.

Further, this coil frame has a positioning fixing portion, and this positioning fixing portion is a fixing member for supporting the lens holding member by a plurality of linear spring members in a cantilever manner and fixing the linear spring members at the other end. Since it is possible to position naturally just by mounting it, it is possible to easily attach the coil frame, that is, the position of the coil to the lens holding member that holds the magnet, that is, the magnet relative to the magnet, in combination with the improvement of the soldering method. The electromagnetic drive of the objective lens can be accurately performed, and the coil frame can prevent the lens holding member from being locked or dust from entering.

As described above, the present invention reduces the number of parts,
By reducing the number of processing points, it is possible to reduce the number of man-hours and the defect rate, improve the productivity, and improve the processing accuracy by improving the structure.

[Brief description of drawings]

FIG. 1 is an external perspective view of an objective lens actuator according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the objective lens actuator.

FIG. 3 is an enlarged perspective view of the coil frame,

FIG. 4 (a) is an assembled perspective view showing an electric connection method to the coil frame, and FIG. 4 (b) is a sectional view showing another electric connection method to the coil frame.

FIG. 5 is an external perspective view of a conventional objective lens actuator.

FIG. 6 is an exploded perspective view of the objective lens actuator.

FIG. 7 is a sectional view of an essential part showing the mounting portion of the electromagnetic coil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens 2 Lens holder (lens holding member) 3 Magnet 5 Coil frame 5a Winding part 5b Covering part 5c Projection part 5d Upper surface 5e, 5f Line processing groove 5g Positioning fixed hole (positioning fixing part) 5h Expansion part 5i Shallow groove part 6 Electromagnetic Coil 6c Lead Wire 6d Edge 8 Suspension Wire (Linear Spring Member) 10 Housing (Fixing Member) 12 Flexible Printed Circuit Board 12a Print Pattern 12b Terminal Pattern 12d Edge Part 12e Through Hole Processing Section

Claims (10)

[Claims] 1. A winding part for winding coils in different biaxial directions into two layers, a covering part connected to the winding part for covering the inside thereof, and a covering part provided on the covering part for covering the inside of the coil. A coil frame having a plurality of wire treatment grooves for winding respective lead wires at the beginning and end of winding and a solder treatment portion provided on the lead wire wound around the wire treatment groove in a part of the wire treatment groove. Objective lens actuator equipped. 2. The objective lens actuator according to claim 1, wherein the solder-processed portion is on an end surface of the coating portion. 3. The objective lens actuator according to claim 1, wherein the solder-processed portion is on a plane portion of the coating portion. 4. The objective lens actuator according to claim 2, further comprising a shallow groove portion in which the depth of the line processing groove is partially reduced in the solder processing portion. 5. The objective lens actuator according to claim 1, wherein the coil frame is formed of a synthetic resin material having heat resistance equal to or higher than a solder melting temperature. 6. The objective lens actuator according to claim 1, wherein a flexible printed circuit board having a corresponding conductive foil is brought into contact with and soldered to the soldering portion. 7. A lens holding member for holding an objective lens, a plurality of linear spring members for supporting the lens holding member, a fixing member for fixing the linear spring member, and two coils having different biaxial directions. An objective lens actuator comprising: a coil frame connected to a winding part wound around a layer and having a positioning and fixing part for the fixing member. 8. The objective lens actuator according to claim 7, wherein the lens holding member has a pair of magnets fixed by adhesion or molding. 9. The objective lens actuator according to claim 7, wherein the coil frame has a protrusion or an extension for locking the lens holding member. 10. The objective lens actuator according to claim 7, wherein the coil frame having the expansion portion, the frame-shaped fixing member, and the lens holding portion form a substantially box-shaped structure.