JP2846805B2 - Objective lens drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device for optically reading information recorded on a disk-shaped recording medium, and more particularly to an objective lens driving device for focusing light from a light source on the recording medium.

[0002]

2. Description of the Related Art Conventionally, a lens holder for holding an objective lens is elastically supported so as to be displaceable in a focus direction and a tracking direction by a plurality of elastic support members having conductivity and appropriate elasticity, and is mounted on the lens holder. There is an objective lens driving device configured to supply power to each of the focusing and tracking coils via the elastic support member, and an example thereof will be described with reference to FIG.

In FIG. 4, reference numeral 1 denotes a lens holder holding an objective lens 2 and mounted with focusing and tracking coils (not shown in the drawing), and 3 mounted on both side surfaces of the lens holder 1. The holder substrate 4 for supplying power to both coils is provided with a yoke 5 on the upper surface.
And a base on which a magnet 6 is provided to form a magnetic circuit, 7 is a base substrate mounted on the base 6, 8 is conductive and has an appropriate elasticity, and both ends thereof are soldered to the holder substrate 3 and the base substrate 7. The elastic support member 8 elastically supports the lens holder 1 so as to be displaceable in a focus direction and a tracking direction, and a part of the both coils is magnetic circuit. It is configured to be located in the upper magnetic gap.

In the objective lens driving device having such a configuration, both coils are energized via the base substrate 7, the elastic support member 8 and the holder substrate 3, and the energization control controls the focus of the lens holder 1 including the objective lens 2. Focus control and tracking control are performed by displacing in the direction and the tracking direction.

[0005]

In the objective lens driving device, the pattern printing surface 7a of the base substrate 7 is provided on the surface opposite to the lens holder 1, and the pattern printing surface 7a is elastically supported on the land. Since the end of the member 8 is attached to the solder 9 from the front thereof,
An end portion of the elastic support member 8 and a protruding portion 7b made of solder 9 for fixing the end portion are formed on the pattern printing surface 7a. Particularly, in order to increase the fixing strength of the solder portion, the width of the end portion of the elastic support member 8 is reduced. If a sufficient soldering margin is obtained by increasing the size, the dimension A of the protruding portion 7b becomes large, which results in an increase in the size of the objective lens driving device and, consequently, the size of the optical pickup device and the disk reproducing device in which the objective lens driving device is mounted. connection,
In particular, it cannot be said that such a device is not particularly preferable for use in a device that requires a smaller size, such as a portable device for reproducing a small-diameter disk called a mini disk (MD).

The end of the elastic supporting member 8 is connected to the base substrate 7.
Since the soldering is carried out simply on the land, the end fixing position of the elastic support member 8 is likely to be shifted,
This has led to variations in performance and has problems in reliability. However, the present invention provides an objective lens driving device which is more compact and more suitable in terms of reliability.

[0007]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of solving the above-mentioned problems, and comprises a lens holder for holding an objective lens and mounting respective coils for focusing and tracking, and the lens holder. And a holder substrate to which each of the coils is electrically connected,
It has conductivity and moderate elasticity with the base substrate mounted on the base, and both ends are fixed to the holder substrate and the base substrate by soldering, respectively, and the lens holder is elastically displaceable in the focus direction and the tracking direction. An objective lens driving device comprising a plurality of elastic support members for electrically supporting and electrically connecting the two substrates to each other, wherein an end of the elastic support member is positioned on both sides of the base substrate. Forming a recess and positioning it
While providing the lands in order for the recess, and its tip is positioned the end of the elastic support member to the positioning within the recess
It is configured to be fixed by soldering so as to be substantially flush with the surface of the base substrate .

[0008]

[0009]

According to the present invention, therefore, the positioning recess is provided within the positioning recess.
The soldering can be performed with the end of the elastic support member positioned within the positioning recess and the end thereof substantially flush with the surface (pattern printing surface) of the base substrate.
It is therefore possible to minimize the amount of projection of the surface of the base substrate, effectively contributes to the miniaturization of the objective lens driving device. In addition, since the soldering is performed in a state where the end of the elastic support member is positioned in the positioning recess, there is no shift in the end fixing position of the elastic support member, which is a cause of the variation in performance, Reliability can be improved, and sufficient fixing strength can be easily obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention shown in FIGS. 1 and 2 will be described in detail below. 1A and 1B are a plan view, a front view, and a side view showing an objective lens driving device according to an embodiment of the present invention, and FIG. 2 is a configuration explanatory view showing a main part of the driving device. In FIGS. 1 and 2, parts common to those in FIG. 4 are denoted by common reference numerals.

In this embodiment, groove-shaped positioning recesses 10 where the ends of each elastic support member 8 are located are formed on both sides of the base substrate 7, while the positioning recesses 10 are formed on the pattern printing surface 7a. A land 7b for soldering is formed on the periphery of a portion where one end is opened.
Although not shown, a desired conductive pattern is formed on the pattern printing surface 7a as is well known in the art, and the land 7b is formed by being connected to the conductive pattern as appropriate.

The land 7b is provided in the positioning recess 1
It is continuously formed up to the inner surface of 0. As shown in FIG. 2, the elastic supporting member 8 is fixed so that the end thereof is positioned flush with the pattern printing surface 7a.
The elastic support member 8 is electrically connected to the conductive pattern of the base substrate 7 by the solder 9. With such a configuration, the elastic support member 8 can be reliably electrically and mechanically connected to the base substrate 7 by soldering 9 and the pattern printing surface 7 of the base substrate 7
The amount of protrusion above a can be suppressed to a very small value, and the size of the objective lens driving device, and furthermore, the size of the optical pickup device and further the size of the reproducing device itself can be more effectively reduced.

FIG. 3 is a diagram showing a parent substrate for producing a base substrate used in the same driving device. The parent substrate 21 is divided into a plurality of base substrates 7 by making a number of cuts 22 in the base substrate 21, and a space between adjacent substrates is formed. The through holes 23 are formed on the cuts 22, while the lands 7b are formed on the pattern printing surface 7a around the through holes 23. Therefore, if each substrate is divided along each cut 22, the base substrate 7 having the semicircular positioning recess 10 accompanying the division of the through hole 23 can be obtained.

[0014]

As described above, according to the present invention, the end of the elastic support member is inserted into the positioning recess of the base substrate and fixed by soldering, whereby the end of the elastic support member is shifted to the fixing position. without causing, and eliminates the variation in terms of performance, with thereby improving the reliability, it is possible to obtain a sufficient fixing strength, moreover, the leading end of the elastic support members
Make it almost flush with the surface of the base substrate (pattern printed surface)
Therefore, the amount of protrusion from the base substrate in the direction opposite to the lens holder due to the fixing of the end of the elastic support member can be reduced, and the objective lens driving device can be efficiently reduced in size. For example, it is possible to provide an objective lens driving device suitable for a device for reproducing a small-diameter disk called a minidisk, particularly a portable type.

[Brief description of the drawings]

FIG. 1 shows an objective lens driving device according to an embodiment of the present invention, wherein (a) is a plan view, (b) is a front view, and (c) is a side view.

FIG. 2 is a configuration explanatory view showing a main part of the driving device.

FIG. 3 is a view showing a parent board for producing a base board used in the driving device.

4A and 4B show a conventional objective lens driving device, wherein FIG. 4A is a plan view, FIG. 4B is a front view, and FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lens holder 2 Objective lens 3 Holder board 4 Base 7 Base board 7a Pattern printing surface 7b Land 8 Elastic support member 9 Solder 10 Positioning recess

Claims (1)

(57) [Claims] 1. A lens holder for holding an objective lens and mounting respective coils for focusing and tracking, a holder substrate mounted on the lens holder and electrically connecting the respective coils, and mounted on a base. And a base substrate having conductivity and moderate elasticity, both ends of which are fixed to the holder substrate and the base substrate by soldering, respectively, to elastically support the lens holder so as to be displaceable in a focus direction and a tracking direction. And a plurality of elastic support members for electrically connecting the two substrates, and a positioning recess in which ends of the elastic support members are formed on both sides of the base substrate. and and concave for the positioning
While providing the land portion, to position the ends of the elastic support member to the positioning within the recess and Jo whose tip is approximately flush with the surface of that portion of the base substrate
An objective lens driving device characterized by being fixed by soldering in a state .