JPS61120354A - Driver of optical device - Google Patents

Abstract

PURPOSE:To make a leading line from a movable part unnecessary and to increase the work efficiency in assembling by placing a yoke on a fixed stand to come into contact with the outer periphery of a focus controlling coil and winding a track controlling coil on a part of the circumference of the yoke at right angles to the focus controlling coil. CONSTITUTION:A holder 3 is held by a supporting shaft 1. It is rotatable and slidable along the supporting shaft 1. An objective lens 4 is fixed at a fixed distance from the supporting shaft 1. A cylindrical permanent magnet 11 is fixed to the holder 3, and the permanent magnet 11 rotates and slides with the holder 3. A coil 13 for focus control is places on the fixed stand while keeping a small space from the permanent magnet 11. Yokes 14a, 14b are arranged on the fixed stand 12 to come into contact with the outer circumference of the focus controlling coil 13. Track controlling coils 15a, 15b are wound around a part of the circumference of yokes 14a, 14b at right angles to the focus controlling coil 13. As the focus controlling coil and track controlling coil are not wound round the holder, the coil wire is not led out from the holder.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an optical means drive device employed in an optical disc player, etc., and particularly relates to an optical means driving device used in an optical disc player, etc. The present invention relates to an optical means driving device that detects the deviation of the light spot from the track of the disk, drives the optical means according to the detected amounts, and appropriately controls the position of the optical means.

[Conventional technology]

A conventional optical means drive device is shown in FIGS. 6 and 7, in which (l) is a spindle whose surface is coated with a coating material with a low coefficient of friction such as Teflon resin, and (2) is a spindle fi+. (3) is a holder held on the support shaft fi+, which is rotatable around the support shaft (11) and slidable along the support shaft (1). (4) is the objective lens fixed to the holder (3) with a certain relationship with the support shaft (1), (5) is the objective lens barrel, and (61 is the lens wrapped around the holder (3). Attached focus control carp #, (7a), (7'b), (7c)
, (7d) is a track control coil attached to the square of the holder (3) from above the focus control coil (6;
8a), (8b) are permanent magnets arranged in a direction facing the focus control coil (6); (9a);

(9b) is an iron plate attached to the back of permanent magnets (8a) and (sb).

α1 is a rubber elastic body whose one end is fixed to the holder (3) and the other end is fixed to a fixing base (not shown).
It began to give a neutral position to (・ru.

Next, the operation will be explained.

When a shift in focus of a light spot (not shown) with respect to an information recording surface (not shown) of a disk (not shown) on which information is recorded is detected, a predetermined current is applied to the focus control coil (6). Then, the holder (3) comes to slide along the support shaft (1). The objective lens (
4) also moves in the direction of arrow B, so that the position of the objective lens (4) can be properly controlled. When a track deviation of a light spot (not shown) with respect to a track (not shown) of a disk (not shown) is detected, track control coils (7a), (7b), (7c), (7d) are activated.
A predetermined current is applied to the holder (3), and the holder (3) begins to rotate. As the holder (31) rotates, the objective lens (4) also moves in the direction of arrow C, and the position of the objective lens (4) can be controlled appropriately.

[Problem that the invention seeks to solve]

As mentioned above, the conventional optical means interlocking device has a focus control coil (61 and a track control coil 4) attached to the holder (3).
7a), (7b), (7a), (7(1)) Since it is a fully installed moving coil system, the focus control coil (
6 (and track control coils (7a), (7b),
It is necessary to pull out the coil wire from C7c)+ (7d) and hold it in a fixing part (not shown) placed separately from the holder (3). The drawn-out coil wire moves with the movement of the holder (3). From the point of view of preventing breakage, etc., it is good to relay part of the coil wire to a strong lead wire on the holder (3), but if you use a strong lead wire, the strong lead wire will prevent the movement of the holder (3). This is because it disturbs the object and makes it difficult to control the objective lens (4).

- There are major restrictions on the selection of lead wires, and
This invention solves the problems of conventional products, which had the problem of making the work of drawing out the lead wire delicate and making assembly difficult.

It is an object of the present invention to provide an optical means interlocking device that eliminates the need for a lead wire from a movable part and improves work efficiency during assembly.

[Failure to solve the problem]

In the optical means interlocking device according to the present invention, a holder is rotatably and slidably held on a support shaft, an objective lens is fixed to the holder at a constant distance from the support shaft, and a cylindrical permanent magnet is attached to the holder. The focus control coil is fixed to rotate and slide with the holder, and the focus control coil is placed on the fixed base with a small gap between it and the permanent magnet, and the yoke is placed on the fixed base so as to be in contact with the outer periphery of this focus control coil. A track control coil is wound around a part of the circumference of this yoke so as to be perpendicular to the focus ttflml ml coil.

[Effect]

In this invention, a holder and an objective lens.

The permanent magnet becomes movable, but since the focus control coil and track control coil are not attached to the holder, the coil wire cannot be drawn out from the holder. That is, in this invention, the coil wire is no longer drawn out from the movable part.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

1 to 5 show an embodiment of the present invention, in which the holder +31 is held on a support shaft (1), is rotatable around the support shaft (1), and is also rotatable along the support shaft fil. It is possible to slide. An objective lens (4) is fixed to the holder (3) at a constant distance from the support shaft (1). Further, the holder (3) is provided with a counterweight αe having a moment of inertia equivalent to the moment of inertia of the objective lens (4) with respect to the support shaft (1), and dynamic balance around the support shaft (1) is maintained. Further, a cylindrical permanent magnet 0υ is fixed to the holder (3), and the permanent magnet αυ rotates and slides together with the holder (3). On the fixed base a3, the focus control coil αJ is a permanent magnet +I+1
The fixed base α has yokes (14a) and (14b) arranged so as to be in contact with the outer periphery of the focus control coil α3.

Track control coils (15a) and (15b) are wound around part of the circumference of the yokes (14a) and (14b) so as to be orthogonal to the focus control coil +131. York (14a).

If the yoke (14b) is made into an integral cylindrical shape, it will be difficult to wind the track control coils (15a) and (15b).
a).

(14b) is a semi-cylindrical shape that is divided into two parts and then glued together after winding to form a cylindrical shape. Note that on is a light beam emitted from a light source (not shown).

Next, the operation will be explained.

When a defocus of a light spot (not shown) with respect to an information recording surface (not shown) of a disk (not shown) on which information is recorded is detected, a predetermined current is applied to the focus control coil 0, and the permanent magnet αυ becomes VC so as to receive a force in the direction of arrow E shown in FIG. Therefore, the holder (3) is attached to the support shaft (1
). By sliding the holder (3), the objective lens (4) moves to #! The objective lens (4) moves in the direction of the arrow shown in FIG. 2, and the position of the objective lens (4) can be properly controlled.

When a track deviation of a light spot (not shown) with respect to a track (not shown) of a disk (not shown) is detected,
A predetermined current is applied to the track control coils (15a) and (15b), and the permanent magnet aυ is moved by the arrow F shown in FIG.
It begins to receive the rotational force of. Therefore, the holder (3) comes to rotate around the support shaft (1). holder(
The rotation of 3) causes the objective lens (4) to rotate in the direction of arrow C shown in FIG. 1, so that the position of the objective lens (4) can be properly controlled. Yoke (14) without being
a) and (14b) may be non-magnetic materials instead of magnetic materials. Further, instead of the yoke being divided into two parts, any type of yoke may be used as long as it is divided into a plurality of parts.

〔Effect of the invention〕

In this invention, since the focus control coil and the track control coil are not attached to the holder as described above, the coil wire is not pulled out from the movable part, which has the effect of improving work efficiency during one assembly. There is.

[Brief explanation of drawings]

Figures 1 to 5 show embodiments of this invention.
The figure is a plan view, FIG. 2 is a cross-sectional view of FIG. 2, FIG. 3 is a plan view of the focus control coil and track control coil, and FIG. 4 is an assembly procedure for the focus control coil and track control coil. The perspective view and FIG. 5 are explanatory diagrams showing the distribution of magnetic flux. 6 and 7 show a conventional optical means driving device, with FIG. 6 being an assembled perspective view and FIG. 7 being an exploded perspective view. In the figure, (1) is the support shaft, (3) is the holder, (4) is the objective lens, 01) is the permanent magnet, (I3 is the fixed base, t
13 is a focus control coil, (14a), (14b
) is a yoke, (15a) and (15b) are track control coils, and αe is a counterweight. In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (4)

[Claims] (1) A holder rotatably and slidably held on a support shaft, an objective lens fixed to the holder at a constant distance from the support shaft, and an objective lens attached to the holder so as to rotate and slide together with the holder. a fixed cylindrical permanent magnet; a focus control coil placed on a fixed base with a small gap between the permanent magnet; a yoke in contact with the outer periphery of the focus control coil and placed on the fixed stand; An optical means driving device comprising: a track control coil wound around a part of the circumference of the yoke so as to be orthogonal to the focus control coil. (2) The optical means driving device according to claim 1, wherein the yoke is a magnetic material. (3) The optical means driving device according to claim 1 or 2, wherein the yoke is divided into a plurality of parts. (4) The optical means drive according to any one of claims 1 to 3, characterized in that the holder includes a counterweight and is dynamically balanced around a support shaft. Device.