JP2006107563A - Manufacturing method of optical pickup - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve vibration-proof performance of an optical pickup. <P>SOLUTION: In the optical pickup apparatus in which driving coils (tracking coil 4, focus coil 5, tilt coil 6) are attached to a lens holder 2 holding an objective lens 9, in the drive coils, after an aircore coil is made by winding a conducting wire and arranged at the prescribed position of a coil holder 3 consisting of resin molding, a part of the coil holder 3 is heated and deformed and the drive coils are embedded and fixed in the coil holder 3. Further after that, the coil holder 3 is attached to a lens holder 1. Since each drive coil is embedded and fixed in the coil holder 3 and integrated, they are not slipped off easily even if vibration is applied to the optical pickup, consequently, vibration-proof performance can be improved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical pickup device used for irradiating an optical disk with a light beam and receiving a reflected light beam thereof, and more particularly to a method of manufacturing an optical pickup device with a simplified structure for attaching various coils to a lens holder.

  The optical pickup device supports a lens holder that holds an objective lens so that the lens holder can be displaced on a support shaft, and the lens holder includes a focus coil, a tracking coil, and a tilt coil, and the irradiation direction of the light beam from the light source to the optical disk is controlled. A focus mechanism, a tracking mechanism, and a tilt mechanism are provided. The lens holder is caused to act by applying a static magnetic field adjacent to the lens holder, and generating a magnetic field by giving independent drive signals to the focus coil and the tracking coil. Is adjusted in the vertical direction, or tracking adjustment is performed in the horizontal direction.

For example, the following patent documents exist in the technology relating to such an optical pickup device.
JP-A-9-147388 JP 2003-196862 A Japanese Patent Laid-Open No. 9-212888

  In Patent Document 1, a fixed-side holder and a movable-side holder are provided, and an objective lens is attached to the movable-side holder, and a beam member is disposed between the fixed-side holder and the movable-side holder. A structure attached by insert molding of a holder is disclosed. In this optical pickup device, the attitude control drive coil is attached to the movable side holder.

  Further, in Patent Document 2, a cylindrical portion in which a shaft hole through which a support shaft is inserted is formed in a substantially central portion of the lens holder, and a focus coil and a plurality of tracking coils are formed on the outer peripheral portion of the cylindrical portion. It is attached so as to be orthogonal. The cylindrical portion, the focus coil, and the tracking coil are configured as separate members, and each tracking coil has a structure in which the winding center is attached in a direction orthogonal to the central axis of the shaft hole.

  Patent Document 3 discloses an optical pickup in which a coil support plate is attached to a coil bobbin of a focus coil, and a coil is wound around a coil bobbin portion formed on each coil support plate.

  By the way, in such an optical pickup device, the structure made up of the lens holder and various coils is a fine structure, and the configuration for adjusting the objective lens in a desired direction affects the pickup performance due to the installation accuracy of the coil with respect to the lens holder. It will be. The lens holder is a molded body made of synthetic resin, in which a focus coil is arranged on the inner part, a plurality of tracking coils having an inner diameter of 1 mm or less are arranged on the outer part, and these are fixed with an adhesive. However, it is difficult to control the adhesive application position and its quantification, and a highly precise arrangement position between the focus coil and the tracking coil is required, so the adhesive between the lens holder and the focus coil, and the focus coil and the tracking coil. It has been pointed out that there are inconveniences such as a decrease in yield and poor working efficiency. Further, the configuration in which the coil support plate is installed on the coil bobbin of the focus coil or the coil is wound around the coil bobbin formed on the coil support plate has the disadvantage that the number of parts is large, the structure is complicated, and the workability is poor. is there.

  Accordingly, the applicant is an optical pickup device comprising a holder for holding an objective lens, and a focus coil and a tracking coil attached to the holder according to Japanese Patent Application No. 2003-407610, wherein the holder is a resin molded body. The focus coil is embedded and fixed in the resin molded body, and the tracking coil is attached to the mounting portion formed on the holder, thereby solving the above-described problem.

  However, with the recent increase in storage capacity for optical discs, the rotation speed of optical discs and the reading speed have been increased. As the optical disk rotates and the reading speed increases, the optical pickup device needs to improve the rigidity of the lens holder and bring the secondary resonance point to a higher band. come.

  Generally, in order to improve the rigidity of the lens holder, a resin having a large bending elastic modulus is selected, and when the lens holder is molded, the lens holder and the coil are firmly fixed by being integrally formed with the coil. Can be achieved. However, in order to integrally mold the lens holder and the coil, it is necessary to integrally mold the focus coil and the tracking coil, and it is extremely difficult to integrally mold while positioning each coil at an appropriate position. .

  The present invention is for solving the above-described problems, and can position the coil of the optical pickup device by a simple method and increase the bonding strength between the optical pickup device and the coil, thereby increasing the rigidity of the optical pickup device. The present invention provides a manufacturing method capable of achieving the above.

  The invention according to claim 1 of the present application is a method of manufacturing an optical pickup device in which a drive coil is attached to a lens holder that holds an objective lens, and the drive coil is fixed to a coil holder made of a resin molded body. A method for manufacturing an optical pickup device, wherein the coil holder is attached to the lens holder later.

  The invention according to claim 2 is a method of manufacturing an optical pickup device in which a drive coil is attached to an objective lens holder that holds an objective lens, and after the drive coil is fixed to a coil holder made of a resin molded body, In the method of manufacturing an optical pickup device, the coil holder is disposed at a predetermined position, and a lens holder is molded together with the coil holder.

  After the drive coil is fixed to the coil holder, the drive coil can be easily positioned relative to the lens holder if the drive coil is positioned relative to the coil holder by attaching it to the lens holder holding the objective lens holder. . At this time, the lens holder may be molded in advance, and the coil holder may be attached to the molded lens holder, or may be integrally formed with the coil holder to which the drive coil is attached. As a result, the manufacturing process of the optical pickup device is simplified, and the manufacturing cost can be reduced.

  According to a third aspect of the present invention, the drive coil is wound around a conducting wire to form an air-core coil, and is disposed at a predetermined position of a coil holder made of a resin molded body, and then a part of the coil holder is heated and deformed. 3. The method of manufacturing an optical pickup device according to claim 1, wherein the drive coil is embedded and fixed in a coil holder.

  The drive coil is wound around a conductive wire to form an air-core coil, and then placed at a predetermined position of a coil holder made of a resin molded body. Then, a part of the coil holder is heated and deformed, and the drive coil is embedded and fixed in the coil holder. Then, the drive coil is firmly fixed to the coil holder. For this reason, it is possible to improve the vibration resistance of the optical pickup device.

  According to the method of manufacturing an optical pickup device according to the present invention, the positioning of the coil of the optical pickup device can be performed by a simple method, the bonding strength between the optical pickup device and the coil can be increased, and the rigidity of the optical pickup device can be increased. become able to. Further, it is possible to change the number of coil turns of each drive coil attached to the coil holder in accordance with the weight of the lens holder, and the versatility becomes high.

  An embodiment of a method for manufacturing an optical pickup device of the present invention will be described with reference to FIGS. FIG. 1 is an exploded perspective view showing an optical pickup device being assembled, and FIG. 2 is a drawing showing a process of attaching a coil to a coil holder of the optical pickup device.

  As shown in FIG. 1, the lens holder 1 is formed in a substantially rectangular parallelepiped shape, and the objective lens 2 is mounted on the upper surface. The objective lens 2 faces an information recording surface (not shown) of the optical recording medium and focuses or irradiates the information recording surface of the optical recording medium to record or reproduce information. Further, the side surfaces of the lens holder are formed in parallel to each other. The mounting position of the objective lens is arranged at the center position of the side surfaces formed in parallel. Coil holders 3 and 3 are attached to the side surfaces of the lens holder, respectively.

  A tracking coil 4, a focus coil 5, and a tilt coil 6 are attached to the coil holder 2, and the respective coils are arranged at point-symmetrical positions around the objective lens 9 of the lens holder 2. As a result, the lens holder 2 and the coil holder 3 attached to both side surfaces of the lens holder 2 are integrated, and the center of gravity of the optical pickup device 1 is positioned on the optical axis of the objective lens 2.

  Three wires 8 are attached to each of the other side surfaces of the lens holder 2 to which the coil holder 3 is attached. The wire 8 is fixed to a base (not shown in the figure) of the optical pickup device 1, and the optical pickup device 1 shown in FIG. 1 is held by the six wires with respect to the base. By being held by the wires 8 in this way, the position and inclination of the optical pickup device are adjusted by each drive coil.

  The optical pickup device 1 as described above is produced as follows.

  The lens holder 2 is molded using a resin material such as a liquid crystal polymer. If desired moldability and rigidity can be obtained, various engineering plastics can be used as a resin material for molding the lens holder 2. The lens holder 2 is formed with a lens storage hole for storing the objective lens 9, and the objective lens 9 is stored in the lens storage hole.

  The coil holder 3 is formed of the same kind of resin material as the lens holder 1, and the coil holder 3 includes a tracking coil, a focus coil, and a tilt coil wound in a rectangular shape.

  The process of attaching the drive coil to the coil holder 3 will be described with reference to FIG.

  The coil holder 3 is plate-shaped and has a storage hole 3A in which each coil can be stored. In addition, a wall portion 3B having a large plate thickness is formed so as to surround the storage hole 3A. 2A, the tracking coil 4, the focus coil 5 and the tilt coil 6 are accommodated in the accommodation hole 3A of the coil holder 3. As shown in FIG. FIG. 2B shows a state in which the tracking coil 4, the focus coil 5, and the tilt coil 6 are accommodated in the coil holder 3 in the accommodation hole 3A. Then, as shown in FIG. 2C, the pressing jig 10 is pressed against the wall 3 </ b> B of the coil holder 3. The press jig 10 has a configuration in which a contact portion is formed flat and can be heated by a heater or the like. The pressing jig 10 is heated and pressed against the wall portion 3B of the coil holder 2 to thermally melt the wall portion 3B, and by pressing the wall portion 3B, the molten resin becomes the tracking coil 4, respectively. The focus coil 5 and the tilt coil 6 are covered.

  Thereafter, when the press jig 10 is separated, the melted resin is hardened again, and each drive coil is fixed to the coil holder 3. At this time, as shown in FIG. 2D, the molten resin is cured in a flat state by the pressing jig 10. By such a process, each coil can be fixed at a predetermined position of the coil holder.

  In order to arrange each drive coil at a predetermined position with respect to the coil holder, the size of the storage hole of the coil holder is substantially matched with the size of each drive coil, and the tolerance is formed to reduce the tolerance, It can be arranged at a certain position. In addition, each drive coil can be arranged at a fixed position with respect to the coil holder by positioning the coil holder and each drive coil according to the positioning reference.

  Thus, by attaching the tracking coil, the focus coil, and the tilt coil to the coil holder in advance, the relative position of each coil becomes constant. Then, by attaching the coil holder to the lens holder, each coil can be easily positioned with respect to the lens holder.

  That is, the positions of the six drive coils with respect to the lens holder can be fixed by attaching the coil holder to the lens holder while performing relative positioning between the coil holder and the lens holder.

  And since each coil is being fixed to the coil holder in the state welded, the attachment strength of the coil holder of each coil will also become strong, and vibration-proof performance will also improve.

  In addition to the above manufacturing method, it can also be manufactured by the following manufacturing method.

  In the same manner as in the above-described embodiment, after attaching each drive coil to the coil holder, the coil holder is housed in a predetermined position of the resin molding frame, and a molten resin is injected into the resin molding frame to mold the lens holder. To do. Thus, the coil position in the lens holder can be properly positioned also by integrally molding the coil holder and the lens holder.

It is a disassembled perspective view which shows the principal part of an optical pick-up apparatus. It is drawing which shows the process of attaching each drive coil to a coil holder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical pick-up apparatus 2 Lens holder 2A accommodation hole 3 Coil holder 3A accommodation hole 3B Wall part 4 Tracking coil 5 Focus coil 6 Tilt coil 8 Wire 9 Objective lens 10 Press jig

Claims (3)

A method of manufacturing an optical pickup device in which a drive coil is attached to a lens holder that holds an objective lens,
The method of manufacturing an optical pickup device, wherein the drive coil is fixed to a coil holder made of a resin molded body, and then the coil holder is attached to the lens holder. A method of manufacturing an optical pickup device in which a drive coil is attached to a lens holder that holds an objective lens,
A method of manufacturing an optical pickup device, wherein the drive coil is fixed to a coil holder made of a resin molded body, the coil holder is disposed at a predetermined position, and a lens holder is molded together with the coil holder.   The drive coil is wound around a conductive wire to form an air-core coil, and is disposed at a predetermined position of the coil holder made of a resin molded body, and then a part of the coil holder is heated and deformed to convert the drive coil into the coil. The method of manufacturing an optical pickup device according to claim 1, wherein the method is embedded and fixed in a holder.