JPH0419615Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to an optical pick-up device for optically picking up information recorded on a disk, and particularly relates to an objective lens of the optical pick-up device. The present invention relates to an optical pickup device that can easily energize a tracking coil and a focusing coil for driving an optical pickup device.

(B) Prior Art An optical pickup device is known that uses a light beam to extract information from a digital audio disk on which unevenness corresponding to a digital signal is engraved. In the optical pickup device described above, in order to correctly project the light beam onto the irregularities on the disk, it is necessary to perform tracking control and focusing control of the objective lens. Therefore, in a typical optical pick-up device, a tracking coil and a focusing coil are wound around a lens holder that holds an objective lens, and a control signal is applied to the tracking coil and focusing coil to control the objective lens. controls the position of Therefore, in the optical pickup device, it is necessary to support the lens holder in a movable manner and to form a circuit for applying a control signal to the tracking coil and focusing coil.

For example, in Figure 1 of Japanese Patent Application Laid-open No. 57-127934,
A method of using a support device made of a viscoelastic body to support a lens holder is shown, and FIG. 3 of the publication shows an improved method thereof. According to the method described in the above publication (particularly the method shown in FIG. 3), it is possible to support the lens holder strongly against twisting.

(c) Problems to be solved by the invention However, in the method of the above-mentioned publication, electrical conductivity cannot be obtained because the support is made of a viscoelastic material such as rubber. A separate means for supplying electrical signals to the coil was required.

(d) Means for solving the problems The present invention was created in view of the above points, and uses four support wires made of conductive material to support the lens holder, and a tracking coil. The present invention is characterized in that one end and the other end of the focusing coil are electrically connected to the four support wires, respectively.

(E) Effect According to the present invention, the support wire for supporting the lens holder can be used as a lead wire for the tracking coil and the focusing coil, thereby eliminating the need for a special electric circuit.

(F) Embodiment FIG. 1 is a perspective view showing an embodiment of the present invention.
Reference numeral 1 denotes a lens holder in which an objective lens 2 is arranged and fixed in an integrally molded cylinder 1a, 3 a tracking coil wound around the lens holder 1, and 4 a focusing coil wound around the lens holder 1. Coil, 5 is aluminum die-cast frame,
Reference numeral 6 denotes a mounting portion 5 of the frame 5 for forming a magnetic field.
Permanent magnets 7 to 10 fixed to a are first to fourth support wires that are strong and conductive, such as phosphor bronze. Therefore, one end of the first to fourth support wires 7 to 10 passes through the hole of the frame 5 and extends to the printed circuit board 11.
The other end passes through the hole of the frame 5 and is inserted into the hole 13 of the hole member 12, and the center part is fixed to the lens holder 1 with adhesive.
Moreover, as shown in FIG. 2, two parts 3a and 3
In the tracking coil 3, which is divided into two parts, the ends of the two parts 3a and 3b are connected to each other, and the end of the part 3a is connected to the first support wire 7, and the end of the part 3b is connected to the first support wire 7. It is electrically connected to the second support wire 8. Although not shown, the ends of the focusing coil 4 are similarly electrically connected to the third and fourth support wires 9 and 10, respectively.

Now, in order to perform tracking control of the objective lens 2, when a tracking control signal is applied to the printed circuit board 11, the tracking control signal is applied to the tracking coil 3 via the first and second support wires 7 and 8. Tracking coil 3
Since a current flows through the lens holder 1, the lens holder 1 moves in the tracking direction (arrow A-A') in relation to the lines of magnetic force of the permanent magnet 6. At this time, the moving direction of the lens holder 1 is determined according to the polarity of the applied control signal, and the moving distance of the lens holder 1 is determined according to the magnitude of the tracking control signal.

On the other hand, in order to perform focusing control of the objective lens 2, when a focusing control signal is applied to the printed circuit board 11, the focusing control signal is applied to the focusing coil 4 via the third and fourth support wires 9 and 10, Since current flows through the focusing coil 4, the lens holder 1 moves in the focusing direction (arrow B-B'). At this time, as in the case of tracking control, the moving direction of the lens holder 1 is determined according to the polarity of the applied control signal, and the moving distance of the lens holder 1 is determined according to the magnitude of the control signal.

One end of the first to fourth support wires 7 to 10 is fixed to a printed circuit board 11 by soldering, as shown in FIG. 2, and the other end of the first to fourth support wires 7 to 10 is As shown in FIG. 3, the frame 5 is filled with dump material 14.
It is simply inserted into the hole 12a of the hole member 12 through the hole 5b. Therefore, when a force in the direction of arrow C is applied to the first support wire 7 due to focusing control, for example, the first support wire 7 slightly slides in the direction of arrow D in the holes 5b and 12a.
Since the arm is bent in the direction of arrow C, the lens holder 1 can be moved freely according to the control signal.
Similarly, when a force in the direction opposite to the arrow C direction is applied due to focusing control or when tracking control is performed, the first support wire 7 slides slightly in the holes 5b and 12a, and the first The arm of the support wire 7 can be bent in the direction in which the force is applied.

Next, the assembly of the optical pickup device according to the present invention will be explained. When assembling,
First, the lens holder 1, around which the tracking coil 3 and the focusing coil 4 are wound, is placed at a predetermined position on the frame 5, and then the first to fourth support wires 7, each of which has one end fixed to the printed circuit board 11 by soldering. 10 is inserted into the hole of the frame 5 from the outside, and further inserted into the hole of the mounting part 1b of the lens holder 1, and then the hole 5b of the frame 5 and the hole member 12 are inserted.
into the hole 12a. Then, the first to fourth support wires 7 to 10 and the mounting portion 1b of the lens holder 1 are adhesively fixed, and the first to fourth support wires 7 to 10 are connected to the tracking coil 3 and the focusing coil. The assembly is completed by electrically connecting the ends of 4.
Since the frame 5 is made of aluminum die-casting, it has electrical conductivity. On the other hand, since the first to fourth support wires 7 to 10 are used as lead wires for supplying control signals to the tracking coil 3 and focusing coil 4,
If the fourth support wires 7 to 10 come into contact with the frame 5, a short circuit will occur. However,
In this invention, in order to prevent the short circuit accident,
The holes in the frame 5 on the side to which the printed circuit board 11 is fixed are made sufficiently larger than the diameters of the first to fourth support wires 7 to 10, and the holes in the frame 5 on the side to which the hole member 12 is fixed are made to be sufficiently larger than the diameters of the first to fourth support wires 7 to 10. Fourth support wire 7
The diameter of the dumping material 14 is larger than that of the holes 1 to 10, and the dumping material 14 is inserted into the holes. The dump material 14
also has the effect of suppressing unnecessary vibrations of the first to fourth support wires 7 to 10.

(g) Effects of the invention As described above, according to the invention, the conductive support wire has the role of supporting the lens holder and the role of supplying current to the tracking coil and focusing coil. Therefore, there is no need for a special configuration for energization, the structure is simplified, and unnecessary increase in weight is suppressed.
Moreover, it is possible to provide an optical pickup device that is easy to manufacture.

In particular, according to the present invention, one end of the plurality of support wires is directly soldered and fixed to the printed circuit board fixed to the frame, so that the connection for connecting the printed circuit board and each of the support wires is No conductive wires are required, the structure can be simplified, and the positions of the support wires can be easily set using the printed circuit board.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a model diagram showing the connection relationship between the support wire and the tracking coil, and FIG. 3 is the relationship between the support wire and the hole member. FIG. Explanation of main drawing numbers, 1... Lens holder, 2...
...Objective lens, 3...Tracking coil, 4...
...Focusing coil, 5...Frame, 7,
8, 9, 10...Support wire.

Claims (1)

[Scope of utility model registration request] In an optical pickup device that drives an objective lens according to an applied control signal and performs tracking and focusing on a disk,
A tracking coil for tracking, a focusing coil for focusing, a lens holder in which the objective lens is held and around which the tracking coil and the focusing coil are wound, and a plurality of lenses made of a conductive material. It is composed of a book support wire and a printed circuit board to which one end of each of the support wires is fixed by soldering.The printed circuit board is fixed to a frame, and each of the support wires is fixed to a lens holder. is movably supported relative to the frame, and
One end and the other end of the tracking coil and the focusing coil are electrically connected directly to each of the support wires, and by applying a control signal to the printed circuit board, the control signal is applied to each predetermined support wire. An optical pickup device characterized in that an electric voltage is applied to the tracking coil and the focusing coil through the tracking coil and the focusing coil.