KR100310063B1 - Optical pick-up - Google Patents

Abstract

An object of the present invention is to provide a uniform damper effect on a plurality of wires provided between a lens holder and a base.

As means for solving the above problems, a total of four space portions 28 are formed on both sides of the holding portion 26 integrally formed at the rear end of the base 21, two each on one side, and each space portion 28 is provided. ) Is a concave groove shape in which the side surface of the holding portion 26 is opened. One end surface along the longitudinal direction of each space part 28 is the front surface 26a of the holding | maintenance part 26, and the insertion part 29 comprised by the V groove 29a and the U groove 29b in the said part is shown. ). In the assembling step of the optical pickup, the wires 30 are inserted into the space 28 and the insertion passage 29 on the side of the holding portion 26, and a viscoelastic material in the flow state before gelation is removed using a dispenser or the like. After inject | pouring into each space part 28, it gels and wraps the rear end part of each wire 30 with the damper agent 34. As shown in FIG.

Description

Optical pickup {OPTICAL PICK-UP}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup for recording or reproducing information on a medium such as a compact disc or a mini disc. More particularly, the present invention relates to a damper structure of a wire that elastically supports a lens holder in a holding portion of a base.

The optical pickup is roughly composed of a lens holder for holding an objective lens, a base for supporting the lens holder through a plurality of wires, an electronic drive mechanism for driving the lens holder in a focusing direction or a tracking direction, and the like. A type called a moving coil (MC) method in which an electronic drive mechanism is formed by a focus coil and a tracking coil wound on the side and a magnetic circuit fixed on the base side, and a magnetic circuit fixed on the lens holder side and a focus coil installed on the base side. And a moving magnet (MM) type in which the electronic drive mechanism is configured by the tracking coil.

Fig. 6 is an external view showing the main part of a conventional MC optical pickup, and Fig. 7 is a sectional view taken along the line A-A of Fig. 6, which is described in Japanese Patent Application Laid-Open No. Hei 4-121027.

As shown in these figures, the objective lens 1 is provided in the lens holder 2, and the focus coil 3 and the tracking coil 4 are wound around the lens holder 2, respectively. Four wires 5 made of a flexible metal material are fixed to the lens holder 2, and one end of these wires 5 is soldered to the focus coil 3 and the tracking coil 4, respectively. Four recessed parts 7 are formed in the holding member 6 made of a light transmissive material, and the holding member 6 is integrated in a base not shown. Each recess 7 is formed at a predetermined depth from the front surface of the holding member 6 to the inside, and the rear surface of the holding member 6 through a through hole 8 having a diameter substantially equal to the diameter of the wire 5. Is being reached. The other end of each wire 5 is inserted through the recess 7 and the through hole 8, and surrounded by a damper agent 10 filled in the recess 7. The damper agent 10 is made of a viscoelastic material such as a gelled ultraviolet curable resin, and is filled in the recess 7 in a flow state before gelation, and then cured by penetrating the holding member 6 and irradiating with ultraviolet rays. In addition, the other end of each wire 5 is soldered to the land of the circuit board 9 on the back surface of the holding member 6, and each wire 5 is a current flowing through the focus coil 3 and the tracking coil 4. It also serves to induce.

A pair of permanent magnets 12 and 13 are disposed at opposite positions with the focus coil 3 and the tracking coil 4 interposed therebetween, and the permanent magnets 12 and 13 are yoke 11 so that their opposite poles face each other. ) The yoke 11 is provided on the base integral with the holding member 6, and the yoke 11 and the permanent magnets 12, 13 are constituted by a magnetic circuit. As a result, the permanent magnets 12 and 13 generate magnetic flux in the direction intersecting with the directions of the current flowing in the focus coil 3 and the tracking coil 4, that is, in the Y direction, which is the coordinate side of FIG. Therefore, the force generated by the current flowing through the focus coil 3 is generated in both the left and right Z directions, and the lens holder 2 is moved in the focus direction of the objective lens 1. Similarly, a force in the X direction of the coordinate axis also acts by the current flowing through the tracking coil 4, and the lens holder 2 moves in the tracking direction of the objective lens 1. At that time, if the movable portion composed of the objective lens 1 or the lens holder 2 or the like resonates at a frequency determined by its mass and the stiffness of the wire 5, the damper agent of the wire 5 ( 10) the portion enclosed by 10) is also displaced in the X and Z directions of the coordinate axis of FIG. 6, and the distortion generated by the displacement is absorbed by the damper 10, thereby providing the objective lens 1 or the lens holder 2, or the like. Resonance of the movable portion constituted of is suppressed.

By the way, in the conventional optical pickup mentioned above, after inject | pouring an unhardened viscoelastic material into the four recesses 7 opened in the front surface of the holding member 6 using a dispenser etc., it hardened | cured it and each recessed part ( 7) the damper agent 10 is filled in the damper agent 10. Therefore, if the amount of the damper agent 10 in each recess 7 is not the same, the damper agent 10 is applied to the four wires 5. The length becomes uneven (see L1 and L2 in FIG. 7), and unnecessary vibration such as torsion in the movable portion is generated. However, it is very difficult to strictly control the injection amount of the damper agent 10 using a dispenser or the like, which is a factor that degrades the assembly workability of the optical pickup.

In addition, before the damper 10 is filled in the recess 7, the wire 5 must be inserted into the recess 7 at the opening in the front of the retaining member 6, but in front of the retaining member 6; Since the lens holder 2 exists in the grooves, the work of inserting the wires 5 into the corresponding recesses 7 is also cumbersome, which is also a factor that lowers the assembly workability.

Furthermore, such a problem is not limited to the optical pickup of the MC system, but also occurs in the optical pickup of the MM system.

1 is a perspective view showing a state during assembly of an optical pickup according to an embodiment;

2 is a perspective view showing the main portion of FIG.

3 is a cross-sectional view showing a state in which a damper is filled in the space part of FIG. 2;

4 is a plan view showing the optical pickup in the assembled state;

5 is a perspective view of the optical pickup,

6 is an external view showing a main portion of a conventional optical pickup;

FIG. 7 is a cross-sectional view taken along the line A-A of FIG. 6.

* Description of the symbols for the main parts of the drawings *

20: lens holder 21: base

22: connection 23: integrally molded product

25, 27: wire fixing part 26: holding part

28: space portion 29: insertion portion

29a: V groove 29b: U groove

30: wire 31: objective lens

32: electronic drive mechanism 33: adhesive

34: damper

According to the present invention, a space portion filled with a damper is formed into a concave groove shape in which a surface along the longitudinal direction of the wire is opened, and an insertion passage portion for inserting the wire through the front surface of the holding portion continuous to the space portion is formed. In this configuration, since the length of the damper covering the end of the wire is determined by the mechanical dimensions of the space portion formed in the holding portion, a uniform damper effect is applied to all the wires, and unnecessary vibration such as twisting occurs in the movable portion. It is possible to reliably prevent and at the same time eliminate the need to strictly control the amount of damper filling, thereby simplifying assembly work.

In the optical pickup of the present invention, a lens holder for holding an objective lens, a base having a holding portion, a plurality of wires arranged between the lens holder and the holding portion, and an electron for driving the lens holder in a focusing or tracking direction An optical pickup having a drive mechanism and filled with a damper for enclosing an end portion of the wire in a space formed in the holding portion, wherein the insertion passage portion through which the wire is inserted is inserted into a front surface of the holding portion facing the lens holder. The space portion was formed continuously, and the space portion was formed into a concave groove shape in which the surface along the longitudinal direction of the wire was opened.

In this configuration, since the length of the damper covering the end of the wire is determined by the mechanical dimensions of the space portion formed in the holding portion, a uniform damper effect is applied to all the wires, and unnecessary vibration such as twisting occurs in the movable portion. It is possible to reliably prevent and at the same time eliminate the need to strictly control the amount of damper filling, thereby simplifying assembly work.

Preferably, the opening of the space portion is positioned on the side of the holding portion, but the opening of the space portion may be positioned on the upper or lower surface of the holding portion.

In addition, the insertion through portion may be a hole formed in the front surface of the holding portion, but when the notch-shaped insertion through portion opened in the same direction as the space portion, the wire can be inserted in the same direction with respect to the insertion portion and the space portion. Assembly work becomes simpler.

EXAMPLE

1 is a perspective view showing the state during assembly of the optical pickup according to the embodiment, FIG. 2 is a perspective view showing the main part of FIG. 1, and FIG. 3 is a space portion of FIG. Sectional drawing which shows the state which filled the damper agent, FIG. 4 is a top view which shows the optical pickup of the assembled state, and FIG. 5 is a perspective view of the said optical pickup.

When assembling the optical pickup according to the present embodiment, as shown in Fig. 1, an integrally molded article in which the lens holder 20, which forms the movable portion, and the base 21, which forms the fixed portion, are connected through a pair of connecting portions 22 ( 23) is injection molded in advance. At this time, the lens holder 20 is formed with an annular lens holding portion 24 and four wire fixing portions 25 in total, two on each side. On the other hand, the holding part 26 is integrally formed in the rear end of the base 21, and a total of four wire fixing parts 25 are formed on both sides of the holding part 26, and each wire fixing part is provided. A total of four space portions 28 are formed adjacent to the 25.

As shown in FIG. 2, one of the wire fixing portions 27 on the base 21 side has a U-shape located at the valley portion of the V-shaped groove 27a and the V-shaped groove 27a. And the storage part 27c located in the middle of the U-shaped groove 27b, and the remaining wire fixing part 27 is also configured in the same way. The width dimension of the opening end of the V-shaped groove 27a is set sufficiently larger than the diameter of the wire 30 to be described later, but the width dimension of the U-shaped groove 27b is the diameter of the wire 30. The storage portion 27c is wider and deeper than the U-shaped groove 27b. Each wire fixing portion 25 on the lens holder 20 side is also configured in the same manner as the wire fixing portion 27 on the base 21 side, and overlapping description is omitted, but V-shaped grooves 25a and U are omitted. It is composed of a groove 25b and a storage portion 25c.

Each space part 28 is formed in the recessed groove shape which opened the side surface of the holding part 26, and the dimension L of the longitudinal direction of these space parts 28 is set all the same. Moreover, one cross section along the longitudinal direction of each space part 28 is the front surface 26a of the holding | maintenance part 26, and the insertion part 29 is formed in the said part. The insertion passage portion 29 is a notch that opens in the same direction as the space portion 28, and has a V groove 29a having the same slope as the V-shaped groove 27a of the wire fixing portion 27, and a V groove. It consists of U groove 29b located in the valley part of 29a, and the width dimension of U groove 29b is set large enough compared with the diameter of the wire 30. As shown in FIG.

Next, after the injection molding of the integrally molded article 23, the objective lens 31 is attached to the lens holding portion 24 of the lens holder 20, and the lens holder 20 and the base 21 are provided. Each component of the electronic drive mechanism 32 is provided. Since the optical pickup according to the present embodiment is an MM system, a magnetic body composed of a yoke and a magnet is provided on the rear surface of the lens holding part 24, and a focus coil and a tracking coil are provided on the base 21. Furthermore, the wire 30 is hypothesized between the pair of wire fixing portions 25 and 27 on the lens holder 20 and the base 21 side, and each wire 30 is provided with a space portion 28 and an insertion passage portion ( 29). In this case, when the wire 30 is inserted into the wide opening of the V-shaped grooves 25a and 27a from the sides of the lens holder 20 and the retaining portion 26, the wire 30 is V-shaped. Guided by the narrow guide surface of the grooves 25a and 27a, and directed toward the valley portion, the wire 30 is automatically inserted into the U-shaped grooves 25b and 27b formed in the valley portion, so that each wire 30 is connected to the lens holder 20. Simple and accurate positioning with respect to and base. Furthermore, in this embodiment, the lens holder 20 and the base 21 are integrally molded by using the same injection molding die, and the wire fixing portions 25 and the base 21 side of the lens holder 20 side are molded integrally. Since the relative positions of the respective wire fixing portions 27 can be increased to the mold accuracy of the mold, the U-shaped grooves 25b and 27b of the pair of the lens holder 20 and the base 21 are formed. Linearity can be ensured with high accuracy, and each wire 30 can be positioned more accurately.

Then, in the state where each wire 30 is positioned in the U-shaped grooves 25b and 27b, the adhesive 33 is injected into the storage portions 25c and 27c using a dispenser or the like, and the adhesive ( 33 is penetrated into the U-shaped grooves 25b and 27b adjacent to the storage portions 25c and 27c to thereby adhesively fix the respective wires 30 to the corresponding wire fixing portions 25 and 27. After doing so, the viscoelastic material in the fluidized state before gelation is injected into the inside of the open end of each space portion 28 by using a dispenser or the like, and the respective viscoelastic material is gelled to form each wire 30 as shown in FIG. The edge part by the side of the holding | maintenance part 26 in the inside is wrapped by the damper agent 34. FIG. At this time, a predetermined gap is secured between the wire 30 and the insertion part 29, but the injected viscoelastic material is blocked by the circumferential wall of the space part 28 by its viscosity, and the viscoelastic material is inserted into the insertion part 29. It does not flow out of. In addition, when using the ultraviolet curable type | mold together as a material of the adhesive agent 33 and the damper agent 34, using the dispenser etc., the adhesive agent 33 and the damper agent 34 of a non-hardened state are respectively stored 25c, 27c. ) And the damper agent 34 can be UV-cured at the same time after being injected into the cavity and the space part 28, so that the adhesive agent 33 and the damper agent 34 can be simultaneously filled in a series of processes. have. Finally, by cutting both connecting portions 22 of the integrally molded article 23 with a press or the like, the lens holder 20 is connected to four wires with respect to the holding portion 26 of the base 21 as shown in FIGS. 4 and 5. An optical pickup supported elastically at 30 can be obtained.

According to the optical pickup assembled in this way, the length of the damper 34 surrounding the end of the wire 30 is determined by the mechanical dimension (L dimension in FIG. 2) of the space portion 28 formed in the holding portion 26. Therefore, a uniform damper effect is applied to all four wires 30, and it is possible to reliably prevent unnecessary vibration such as torsion from occurring in movable parts of the lens holder 20 and the like. ) The assembly work can not be simplified because it is not necessary to strictly control the filling amount. Moreover, since the insertion part 29 is formed in the notch shape which opened the same direction as the space part 28, the wire 30 is inserted in the same direction with respect to the space part 28 and the insertion part 29. As shown in FIG. The assembly workability can be further improved. Furthermore, the lens holder 20 and the base 21 are integrally molded through the connecting portion 22 in advance, and after the temporary construction of the respective wires 30, the connecting portions 22 are cut to cut the lens holder 20 and the base 21. Since it is configured to separate, the position of the lens holder 20 and the base 21 when the wire 30 is bonded to the wire fixing portions 25 and 27 or the damper agent 34 is filled into the space portion 28. Accuracy is maintained in a state of high accuracy by the connecting portion 22, and as a result, assembly workability can be improved.

In addition, in the above embodiment, the wire fixing portions 25 and 27 are formed in the lens holder 20 and the base 21 integrated through the connecting portion 22, and the connecting portion 22 is cut after the provision of the wire 30. Although the case where the lens holder 20 and the base 21 are separated has been described, the present invention can be applied to the case where the lens holder 20 and the base 21 are separately molded.

In addition, in the above embodiment, the optical pickup of the moving magnet (MM) method has been described, but the present invention may be applied to the optical pickup of the moving coil (MC) method.

The present invention is implemented in the form described above, and the effects described below can be obtained.

In the optical pickup in which a plurality of wires are provided between the lens holder as the movable portion and the holding portion of the base as the fixed portion, and a damper agent is filled in the space formed in the holding portion to wrap the ends of the wires. If the surface is formed in a concave groove shape and an insertion through portion for inserting the wire is inserted into the front surface of the holding portion continuous to the space portion, the length of the damper covering the end of the wire is determined by the mechanical dimension of the space portion formed on the holding portion. As a result, it is possible to reliably prevent the occurrence of unnecessary vibration such as torsion in the movable part and to ensure the damping effect of all the wires. You can simplify the last name. In addition, when the insertion portion is formed in a notch shape having the same direction as that of the space portion, the wire can be inserted in the same direction with respect to the insertion portion and the space portion, thereby simplifying the assembly workability.

Claims (2)

A lens holder for holding an objective lens, a base having a holding portion, a plurality of wires arranged between the lens holder and the holding portion, and an electronic driving mechanism for driving the lens holder in a focusing or tracking direction, In the optical pickup in which the damper agent surrounding the end of the wire is filled in the space formed in the holding portion, An insertion passage portion through which the wire is inserted is formed on the front surface facing the lens holder of the holding portion, and the surface portion is formed continuously in the insertion passage portion, and the surface along the longitudinal direction of the wire portion of the space portion is formed. An optical pickup, characterized in that it has an open concave groove shape. The optical pickup according to claim 1, wherein the insertion through portion is a notch which opens in the same direction as the space portion.