JPH05128560A - Driving apparatus of objective lens - Google Patents

Abstract

PURPOSE:To easily insert an objective lens driving device to a window frame of a small cartridge by projecting a supporting point supporting the other end of a focusing leaf spring of a relay member towards a lens holding member. CONSTITUTION:This objective lens driving device has supporting points 5a, 5b, 5c, 5d for supporting the other ends of focusing leaf springs 4a, 4b, 4c, 4d of a relay member 5 projected to the side of a lens holding body 3. Accordingly, it becomes possible to ensure the supporting and welding area of the other end of the leaf spring 4a or 4b at the supporting point 5a or 5b further closer to the lens holding body 3. The opposite area of the supporting point 5a or 5b of the relay member 5 can be cut to a predetermined limit. As a result, the objective lens driving device 1 can be easily inserted into a window frame of a small cartridge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens driving device, and more particularly to an objective lens driving device used for an optical head of an optical disk device.

[0002]

2. Description of the Related Art A conventional example of this type is shown in FIGS. In these figures, FIG. 3 is a view of the conventional objective lens driving device as seen from above, and FIG. 4 is a view of the objective lens driving device as shown in FIG. 3 as seen laterally (in the direction of arrow H in FIG. 3). ..

This type of objective lens driving device includes a lens holder 52 for holding the objective lens 52, and four focusing leaf springs 54a, 54 for the lens holder 52.
relay member 55 supported via b, 54c, 54d,
The left side of the relay member 55 (the left side shown in FIGS. 3 to 4)
Fixing portion 57 for supporting the vehicle through the leaf spring 56 for tracking.
And is configured.

This will be described in more detail. Lens holder 53
Four protrusions 53a, 53b, 53c, and 53d protruding from the lens holder 53 are formed in each of them. Of these, the protrusions 53a and 53d are arranged so as to face each other, and one of the center portions of the lens holder 53 on the longitudinal side (see FIG. 3).
It is provided so as to project outward from the upper center portion of the lens holding body 53 shown in FIG. Specifically, the protruding portion 53a is arranged along the upper bottom surface of the lens holding pair 53 on which the objective lens 52 is mounted, and the protruding portion 53d is arranged along the lower bottom surface of the lens holding pair 53 ( 3 to 4).

Further, the projecting portions 53b and 53c project outward from the other central portion on the longer side of the lens holding body 53 (the lower central portion of the lens holding body 53 shown in FIG. 3) while facing each other. It is set up. Specifically, the protruding portion 53b is arranged along the upper bottom surface of the lens holding pair 53 on which the objective lens 52 is mounted, and the protruding portion 53c is arranged along the lower bottom surface of the lens holding pair 53 ( 3 to 4
reference).

The lens holder 53 has four focusing leaf springs 54 arranged at a predetermined distance from the four protrusions 53a, 53b, 53c and 53d.
It is supported by the relay member 55 via a, 54b, 54c, 54d. As shown in FIG. 4, the four focusing leaf springs 54a, 54b, 54c, 54d are arranged such that the leaf pressure directions thereof are all in the direction of the axis 52A of the objective lens 52.

The relay member 55 is supported by a fixing portion 57 arranged between the lens holder 53 and the relay member 55 via a tracking leaf spring 56. The tracking plate spring 56 has a plate pressure direction perpendicular to the axis 52A of the objective lens 52 (arrows A and B shown in FIG. 3).
Direction). In addition, the fixed portion 57,
The support base material 60 is provided so as to project from the support base material 60.

[0008]

However, in the above-mentioned conventional example, since the distance from the objective lens to the relay member is relatively long, the entire surface on the objective lens side becomes large, which hinders downsizing of the mounting frame body. There was an inconvenience of causing

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an objective lens driving device which is intended to improve the disadvantages of the conventional example, and in particular to reduce the area occupied by the objective lens.
To that end.

[0010]

According to the present invention, a lens holder for holding an objective lens, a lens holder supported at one end, and the lens holder reciprocates in a direction along an axis of the objective lens. Four focusing leaf springs arranged at a predetermined distance to allow the focusing leaf spring, and a relay member supporting the other end of the focusing leaf spring,
The lens holder is provided between the relay member and the lens holder to support the lens holder via the relay member and allows the lens holder to reciprocate in a direction orthogonal to the axis of the objective lens. An objective lens driving device having a leaf spring for tracking is provided. Then, a supporting portion for supporting the other end of the focusing leaf spring of the relay member is provided so as to project toward the lens holding body side. This is trying to achieve the previously mentioned objectives.

[0011]

It is possible to secure the supporting pressure-bonding force region at the other end of each focusing leaf spring at the supporting point of the relay member by making it close to the lens holder side. Therefore, the region of the relay member on the opposite side of the support portion can be cut with a predetermined limit.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In these figures, FIG. 1 is a view of the objective lens driving device 1 according to the present embodiment as viewed from above, and FIG. 2 is a diagram showing the objective lens driving device 1 shown in FIG. ) Shows the figure seen from.

The objective lens driving device 1 shown in FIGS. 1 and 2 includes a lens holder 3 for holding the objective lens 2.
This lens holder 3 is supported at one end and at the same time, the four lens holders 3 are arranged at predetermined intervals to allow the lens holder 3 to reciprocate in the direction along the axis 2A of the objective lens 2. Leaf springs 4a, 4b, 4c, 4d,
A relay member 5 for supporting the other end of the focusing leaf springs 4a, 4b, 4c, 4d, and a lens holder provided between the relay member 5 and the lens holder 3 via the relay member 5. 3, and a plate spring 6 for tracking that allows the lens holder 3 to reciprocate in a direction orthogonal to the axis 2A of the objective lens 2. Then, the focusing leaf springs 4 a, 4 a of the relay member 5
support points 5a, 5 for supporting the other ends of b, 4c, 4d
b, 5c and 5d are provided so as to project toward the lens holder 3 side.

This will be described in more detail. Lens holder 3
Holds the objective lens 3 at an upper position (upper position shown in FIG. 2) of the central portion thereof in a state of being slightly projected. Further, the lens holder 3 is formed with four protrusions 3a, 3b, 3c, 3d which project from the lens holder 3 and engage with one end of the focusing plates 4a, 4b, 4c, 4d. Has been done.

Of these, the protrusions 3a and 3d are arranged so as to face each other, and the central portion of one longitudinal side of the lens holder 3 (see FIG. 1).
It is provided so as to project outward from the upper center portion of the lens holder 3 shown in FIG. Specifically, the protruding portion 3a is arranged along the upper bottom surface of the lens holding pair 3 on which the objective lens 2 is mounted, and the protruding portion 3d is arranged along the lower bottom surface of the lens holding pair 3 ( 1 and 2).

The projecting portions 3b and 3c project outward from the other longitudinal center portion of the lens holder 3 (the lower central portion of the lens holder 3 shown in FIG. 1) in a state of facing each other. It is set up. Specifically, the protruding portion 3b is arranged along the upper bottom surface of the lens holding pair 3 on which the objective lens 2 is mounted, and the protruding portion 3c is arranged along the lower bottom surface of the lens holding pair 3 ( 1 and 2).

The lens holder 3 has four focusing leaf springs 4a, 4b, 4 which are arranged at a predetermined distance from the four protrusions 3a, 3b, 3c, 3d.
It is supported by the relay member 5 via c and 4d. The four focusing leaf springs 4a, 4b, 4
The plate pressure directions of c and 4d are all arranged so as to face the direction of the axis 2A of the objective lens 2. Therefore, the objective lens holder 3 is capable of reciprocating with respect to the relay member 5 in the direction of the axis 2A of the objective lens 2 shown in FIG.

The relay member 5 is supported by a fixing portion 7 arranged between the lens holder 3 and the relay member 5 via a leaf spring 6 for tracking. The leaf spring 6 for tracking is arranged such that the leaf pressure direction thereof is a direction (directions of arrows D and E shown in FIG. 1) orthogonal to the axis 2A of the objective lens 2. Therefore, the objective lens holder 3, the focusing leaf springs 4a, 4b, 4c, 4d and the relay member 5 are capable of reciprocating in the directions of arrows D and E shown in FIG. .. The fixed portion 7 is mounted on the support base material 20 in a state of protruding from the support base material 20.

Support points 5a, 5b, 5c, 5d for supporting the other ends of the focusing leaf springs 4a, 4b, 4c, 4d of the relay member 5 are provided so as to project toward the lens holder 3 side. .. These support points 5a, 5b, 5c,
Reference numeral 5d denotes a protrusion 3 protruding from the lens holder 3 described above.
The relay members 5 are arranged in a state corresponding to a, 3b, 3c, and 3d, respectively. Specifically, the support portion 5a and the protruding portion 3a, the support portion 5b and the protruding portion 3b, the support portion 5c and the protruding portion 3c, the support portion 5d and the protruding portion 3d, respectively, correspond to each other, and the above-mentioned is described between them. Each focusing leaf spring 4a, 4b, 4c, 4d is interposed. Then, as shown in FIGS. 1 and 2, the other end of each of the focusing leaf springs 4a, 4b, 4c, 4d is attached to each of the support points 5
It is in a state of being sandwiched between a, 5b, 5c and 5d.

Further, a part 5A on the outer side of the relay member 5, that is, a part on the upper surface (the upper surface shown in FIG. 2) of the relay member 5 and on the opposite side of the tracking leaf spring 6 is an axis 2A of the objective lens 2. Are formed in parallel with each other along a line (arrow D or E shown in FIG. 1) orthogonal to.

As described above, according to this embodiment,
Focusing leaf springs 4a, 4b, 4 of the relay member 5
Support points 5a, 5b, 5 for supporting the other ends of c, 4d
c and 5d are provided so as to project toward the lens holder 3 side.
Therefore, the supporting points 5a to 5 of the relay member 5 are accordingly increased.
It is possible to secure the supporting pressure-bonding force region at the other end of each of the focusing leaf springs 4a to 4d in b by being close to the lens holding body 3 side. Therefore, the region of the relay member 5 on the opposite side of the supporting points 5a and 5b, that is, on the right side (shown in FIGS. 1 and 2) can be cut with a predetermined limit. Therefore, the total length of the device can be shortened, and the area occupied by the objective lens 2 can be effectively reduced. Therefore, the objective lens driving device 1 of this embodiment can be easily inserted into the window frame of a small-sized cartridge.

Further, a part of the upper surface of the relay member 5 (the upper surface shown in FIG. 2) and on the opposite side of the tracking leaf spring 6 is
It is formed as a parallel depression along a line orthogonal to the axis 2A of the objective lens 2. Therefore, even when the objective lens driving device 1 of the present embodiment is placed in the window frame of a small-sized cartridge, the relay member 5 of the objective lens driving device 1 does not hit the window frame. Therefore, it becomes easier to insert the cartridge of the small-sized model of the objective lens driving device 1 of the present embodiment into the window frame, and since the reciprocating operation in each direction in the device is not hindered, the driving efficiency of the entire device is compared. Improve.

[0023]

According to the present invention, which is constructed and functions as described above, according to the present invention, the supporting portion for supporting the other end of the leaf spring for focusing of the relay member is provided so as to project toward the lens holder side. ing. Therefore, the supporting pressure-bonding force region at the other end of each focusing leaf spring in the supporting portion of the relay member can be secured to the lens holder side by that much. Therefore, the region of the relay member on the opposite side of the supporting portion can be cut with a predetermined limit, and the overall length of the device can be effectively shortened. Because of this
The area occupied by the objective lens side in the device is inevitably reduced, and it is possible to provide an excellent objective lens driving device which has not been heretofore available and can be easily inserted into the window frame of a small-sized cartridge.

[Brief description of drawings]

FIG. 1 is a diagram of an objective lens driving device according to a present embodiment as viewed from above.

FIG. 2 is a diagram of the objective lens driving device shown in FIG. 1 viewed from a direction of an arrow F.

3 to 4 are diagrams illustrating a conventional example.

[Explanation of symbols]

 1 Objective Lens Driving Device 2 Objective Lens 2A Axis 3 Lens Holder 4a, 4b, 4c, 4d Focusing Leaf Spring 5 Relay Member 5a, 5b, 5c, 5d Supporting Part 6 Tracking Leaf Spring

Claims (1)

[Claims] 1. A lens holder for holding an objective lens,
Four focusing leaf springs which are arranged at a predetermined interval to support the lens holder at one end and allow the lens holder to reciprocate in a direction along the axis of the objective lens; A relay member that supports the other end of the focusing leaf spring, and a lens holder that is disposed between the relay member and the lens holder to support the lens holder through the relay member. In the objective lens drive device having a tracking leaf spring for allowing reciprocal movement in a direction orthogonal to the axis of the objective lens, a supporting portion for supporting the other end of the focusing leaf spring of the relay member. An objective lens driving device, wherein the objective lens driving device is provided so as to project toward the lens holder side.