JP2000235718A - Optical pickup device and method for assembling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical pickup device having stable quality at a low cost and a method for assembling the same. SOLUTION: This optical pickup device has an objective lens 1 which focuses a laser beam to a disk, a bobbin 2 which is wound with a focusing coil 3 and a tracking coil 4 in part thereof and holds the objective lens 1, four supporting members 7 which are electrically conductively coupled to the focusing coil 3 and the tracking coil 4, movably support the bobbin 2 and have electrical conductivity and elasticity, magnets 5 and 6 which constitute a magnetic circuit for driving the bobbin 2 and a fixing member 8 which supports these supporting members 7. The four supporting members 7 are molded integrally with the fixing member 8. In addition, the right and left spacings (B) of the four supporting members 7 are made larger than the right and left width (A) of the bobbin 2. The bobbin 2 is inserted from behind into the integrally molded supporting members 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a CD player and an MD.
The present invention relates to an optical pickup device used for an optical recording / reproducing device such as a player and a DVD player, and an assembling method thereof.

[0002]

2. Description of the Related Art A disc on which a signal is recorded is reproduced.
Alternatively, in an optical pickup device used for an optical disk device that records a signal on a disk, a laser beam follows a surface deflection in a focus direction and a peripheral deflection in a tracking direction of the disk, and traces a track on which a signal is recorded accurately. Must be configured.

For this purpose, in an optical pickup device, an objective lens is fixed, and a bobbin around which a focus coil and a tracking coil are wound and a bobbin movably held in a focus direction and a tracking direction are usually used. An actuator unit including four support members made of wires and a fixing member for fixing the support member at the other end is required.

Hereinafter, a conventional optical pickup device having such a structure will be described with reference to FIG. 4, reference numeral 1 denotes an objective lens, and reference numeral 2 denotes a bobbin to which the objective lens 1 is fixed. A focus coil 3 and a tracking coil 4 are wound around the bobbin 2. 5 and 6 are magnets
They are arranged so as to face each other with the bobbin 2 interposed therebetween.

[0005] 7a, 7b, 7c and 7d are support members for movably supporting the bobbin 2 and are usually constituted by four wires, one end of each of which is located at the upper, lower, left and right sides of the bobbin 2. The bobbin 2, the focus coil 3, and the tracking coil 4 are connected at four locations, and the other end is fixed to a fixing member 8a. Then, with such a configuration of the actuator section, the drive current controlled by the servo circuit (not shown) is supplied to the focus coil 3 and the tracking coil 4 wound around the bobbin 2 so that the objective lens 1 is moved. Driving in the focus direction and the tracking direction makes it possible to accurately trace signal tracks on a disk even with a disk having eccentricity and runout.

Meanwhile, in this optical pickup device, a configuration of an actuator unit as shown in FIG. 5 has been conventionally devised and implemented in order to improve the holding accuracy of the objective lens 1 and improve productivity. As shown in FIG. 5, the actuator section includes fixing members 8a and 8b that support both ends of support members 7a to 7d before and after a lens holder 10 that holds the objective lens 1. And
The lens holder 10 and the fixing members 8a and 8b before and after the lens holder 10 are integrally formed together with the four support members 7a to 7d, and thereafter, the portions (8) indicated by arrows in FIG.
Cut off unnecessary portions of the support members 7a to 7d at
It is to be removed. FIG. 6 shows the shape after the support members 7a to 7d have been cut and removed.

As described above, the actuator section integrally forms the lens holder 10, the fixing members 8a and 8b, and the supporting members 7a to 7d.
a to 7d and the lens holder 1 for the fixing members 8a and 8b and the temporary fixing members 9a and 9b.
0, the accuracy of supporting the objective lens 1 is improved, and the productivity is also improved.

[0008]

However, in the structure of the actuator section of the optical pickup device, since the focus coil and the tracking coil cannot be wound around the lens holder 10, the magnets 11 and 12 are attached to the lens holder 10, A coil unit 1 in which a focus coil and a tracking coil are wound around positions facing the magnets 11 and 12
A so-called MM (moving magnet) system is adopted in which the magnet holders 3 and 14 are arranged and current is supplied to the coil units 13 and 14 to drive the lens holder 10 and the objective lens 1 together with the magnets 11 and 12. Was. However, in this MM system, there is a problem in that it is necessary to attach a magnet that is small and lightweight and has a high magnetic flux density in order to improve the drive sensitivity, so that it is inevitably expensive.

[0009] In recent years, further reduction in cost and higher reliability have been demanded for disk recording / reproducing devices, and the cost of optical pickup devices, which occupy a particularly large cost among disk recording / reproducing devices, has been reduced. It is becoming necessary. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a low-cost, stable optical pickup device and a method of assembling the same.

[0010]

SUMMARY OF THE INVENTION To solve this problem, an optical pickup device of the present invention reads out a signal recorded on a disk or records a signal on a disk in order to record a signal on the disk. An objective lens for focusing, a focus coil and a tracking coil are wound around a part thereof, and a bobbin holding the objective lens is electrically connected to the focus coil and the tracking coil, and the Four conductive and elastic supporting members for movably supporting the bobbin at four positions, up, down, left and right, a magnet constituting a magnetic circuit for driving the bobbin, and supporting the supporting member A fixing member, wherein the four support members are integrally formed with the fixing member;
The distance between the left and right support members when viewed from above is made larger than the width between left and right when the bobbin is viewed from above, and the bobbin is arranged between the four support members. It is characterized by having done.

As a result, it is possible to obtain a low-cost optical pickup device having stable quality.

[0012]

An optical pickup device according to the first aspect of the present invention reads a signal recorded on a disk or focuses a laser beam on a disk in order to record a signal on the disk. The objective lens, a focus coil and a tracking coil are wound around a part of the objective lens, and a bobbin holding the objective lens is electrically connected to the focus coil and the tracking coil. Four conductive members having conductivity and elasticity, which are movably supported at four positions in the vertical and horizontal directions, a magnet constituting a magnetic circuit for driving the bobbin, and a fixing member for supporting the support member. The four support members are integrally formed with the fixed member, and the four support members are viewed from above. The distance between the right and left of the four support members, wherein greater than the width of the left and right when viewed bobbin from above, is characterized in that said bobbin is arranged between the four support members.

According to a second aspect of the present invention, there is provided a method for assembling an optical pickup device, comprising: a bobbin in which a focus coil and a tracking coil are wound on a part of an objective lens for focusing a laser beam on a disc; Four supporting members having properties and elasticity and movably supporting the lens holder at four positions, that is, up, down, left and right, and a plurality of fixing members supporting the supporting members are integrally assembled. At this time, the four support members are
The four support members are integrally fixed to the fixing member such that a left-right space between the four support members when viewed from above is larger than a left-right width when the bobbin is viewed from above. Then, the bobbin is inserted between the four support members, and thereafter, the ends of the focus coil and the tracking coil are soldered to the support member, and unnecessary portions of the support member are removed. It is characterized by assembling a pickup device.

According to these configurations and methods, the bobbin to which the objective lens, the focus coil, and the tracking coil are assembled can be inserted between the support members to support the bobbin in a good posture. In addition, the unnecessary portion of the support member is removed, and the optical pickup device can be efficiently assembled. Hereinafter, an optical pickup device and an assembling method of the present invention will be described in detail with reference to the drawings.

FIGS. 1, 2 and 3 show the structure of an optical pickup device according to the present invention. FIG. 1 is a perspective view showing a state before a bobbin is mounted on a supporting member. FIG. FIG. 3 is a perspective view showing a state after cutting unnecessary portions of a support member made of a wire. In FIG. 1, reference numeral 1 denotes an objective lens for reading a signal recorded on a disk or focusing a laser on a signal surface of the disk in order to record a signal on the disk. Reference numeral 2 denotes a bobbin to which the objective lens 1 is fixed. The bobbin 2 has a focus coil 3 and a tracking coil 4 wound thereon. Then, both ends of each of the coil wires of the focus coil 3 and the tracking coil 4 are wound around projections 2 a (four places in total) provided on the left and right sides of the bobbin 2.

On the other hand, reference numerals 7a, 7b, 7c and 7d denote supporting members made of conductive and elastic wires, one end of which is held by the fixing member 8a and the other end of which is held by the fixing member 8b. , Are integrally formed with the fixing members 8a and 8b disposed in front and rear of the bobbin 2, respectively. Also,
Reference numerals 5 and 6 denote magnets, which are fixedly arranged between the fixing members 8a and 8b so as to face each other.

Here, in the optical pickup device of the present invention, the four left and right distances between the support members 7a and 7b and the left and right distances (B) between the support members 7c and 7d are defined. The protrusion 2a of the bobbin 2 is configured to be larger than the left-right width direction dimension (A). Therefore,
As shown by arrows in FIG. 1, the bobbin 2 is connected to the support members 7a, 7a.
b, 7c, 7d, and each end of the focus coil 3 and the tracking coil 4 wound around the projection 2a is soldered to the support members 7a, 7b, 7c, 7d. The state shown in FIG. 2 can be obtained. Then, after this, the support members 7a, 7
Unnecessary parts of b, 7c, 7d are cut,
By removing, it is possible to make the state of the actuator as shown in FIG.

As described above, according to the optical pickup device of the present invention, by employing the above-described configuration and method,
Without using expensive magnets, which was a traditional issue,
In addition, the parallelism of each of the four support members 7a, 7b, 7c, 7d and the bobbin 2, with respect to the fixing members 8a, 8b,
Since the accuracy of supporting the objective lens 1 can be improved, an optical pickup device with low cost and stable quality can be obtained.

[0019]

As described above, according to the present invention, the distance between the left and right of the four conductive and elastic supporting members for supporting the bobbin so as to be movable at four positions, that is, up, down, left and right, is set to the bobbin. The width of the left and right sides is larger than that of the previous one, so that the parallelism of each of the four support members and the accuracy of supporting the bobbin and the objective lens with respect to the fixed member can be reduced without using an expensive magnet, which has been a conventional problem. It is possible to obtain an optical pickup device which can be improved and has stable quality at low cost.

[Brief description of the drawings]

FIG. 1 is an exemplary perspective view showing a state of an optical pickup device according to an embodiment of the present invention before a bobbin is attached to a support member;

FIG. 2 is a perspective view showing a state of the optical pickup device after a bobbin is attached to a support member.

FIG. 3 is a perspective view showing a state of the optical pickup device after cutting unnecessary portions of a support member made of a wire.

FIG. 4 is a perspective view showing a conventional optical pickup device.

FIG. 5 is a perspective view showing another conventional optical pickup device.

FIG. 6 is a perspective view showing the optical pickup device of the conventional configuration after the wire is cut.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens 2 Bobbin 3 Focus coil 4 Tracking coil 5, 6 Magnet 7a-7d Support member 8a, 8b Fixing member

Claims (2)

[Claims] An objective lens for focusing a laser beam on a disk for reading a signal recorded on the disk or recording a signal on the disk, and a focus coil and a tracking coil are partially provided on the objective lens. A bobbin wound and holding the objective lens, electrically coupled to the focus coil and the tracking coil, and the bobbin is approximately vertically
It comprises four support members having conductivity and elasticity, which are movably supported at four places on the left and right, a magnet that forms a magnetic circuit for driving the bobbin, and a fixing member that supports the support member, The four support members are formed integrally with the fixed member, and when the four support members are viewed from above,
An optical pickup device, wherein the left and right spaces between the four support members are larger than the left and right widths when the bobbin is viewed from above, and the bobbin is arranged between the four support members. 2. A lens holder for holding a focusing lens and a tracking coil wound on a part of an objective lens for focusing a laser beam on a disk, and having a conductivity and elasticity. When assembling the four support members movably supporting the four positions at the top, bottom, left and right and a plurality of fixing members supporting the support member integrally, the four support members are combined with the four support members. The bobbin is integrally fixed to the fixing member so that the left and right spacing of the four support members when viewed from above is larger than the left and right width when the bobbin is viewed from above. 4
After that, the optical pickup device is assembled by soldering the ends of the focus coil and the tracking coil to the support member and removing unnecessary portions of the support member. Method for assembling an optical pickup device.