JPH01199332A - Manufacture of objective driving device - Google Patents

Abstract

PURPOSE:To cause a position relation between the objective of a mobile body and a base brecise by heating-ageing a hinge body in a condition in which the mobile body and the base are located in a prescribed position relation. CONSTITUTION:A jig 15 has a locating pin 52 to be fit in a through hole 23 of a mobile body 21 and a locating bearing seat 53 to fit with a spherical seat 14 to be concentric to a through hole 12 of a base 11, and by the jig 51, in a condition in which the base 11 and mobile body 21 are mechanically located, an adhesive between the mobile body 21 and a hinge body 34 of a supporting mechanism 34 is cured, thereafter, the base 11, mobile body 21 and supporting mechanism 31 are put in a heating furnace, the heating-ageing is executed at a prescribed temperature for a prescribed time, the hinge body 34 is stroughtened by the ageing, and thereafter, the objective is fit-in-bonded to a fit-in recessed part 22 of the mobile body 21. Thus, the dislocation of the position relation between the fit-in recessed part 22 of the mobile body 21, namely, the objective and the through hole 12 and spherical seat 14 of the base 11 due to the accuracies of working and forming individual components, errors at the time of assembling, etc., can be straightened.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to optical information storage such as optical discs and optical cards.
The present invention relates to a method of manufacturing an objective lens drive device used for a medium.

(Prior Art) In devices that read signals from optical information recording media such as optical discs, signals are detected by focusing laser light onto the information recording medium using an objective lens. , Fi N &! Focusing control to focus the light spot on the signal recording surface of the information recording medium in response to unevenness and vibration of the recording medium, and dragging till to make the light spot follow the signal track.
@is necessary.

In order to perform these i/J m, it is necessary to have an error detection device that detects errors in each of the focusing and tracking directions, and an objective lens drive device that moves the objective lens to cancel out these errors. Become.

As this objective lens driving device, there is one shown in FIGS. 5 to 7.

In Figures 5 to 7, 11 is a plate-shaped base;
This base 11 is made of a magnetic material such as iron, and has a circular through hole 12 bored from the center right end in the drawing, and a notch 13 connected to the left side of the through hole 12.
A spherical seat 14 concentric with the through hole 12 is formed around the through hole 12 and bulges downward.

A support piece 15 is vertically bent upward from the left end of the base 11 in the figure, and a pair of support columns 1G are positioned on the right side of the support piece 15 on the base 11.
Further, yokes 17 are bent vertically and parallel to each other upward from both sides of the center of the base 11, and the yokes 17 are placed inside the yokes 17 on both sides, A pair of yokes 18 on both sides made of the same magnetic material as the base 11 are integrally fixed perpendicularly and parallel to each other, and a magnet 19 is fixed to the inside of each outer yoke 17 by IB 1 or the like. ing.

Reference numeral 21 denotes a movable body, and the movable body 21 is made of a non-magnetic material such as synthetic resin, and has a circular fitting recess 22 and a circular through hole 23 formed from the upper surface to the lower surface of the right end in the drawing. Notch 24 that is convex from the left end toward the center
is formed, and four rectangular mounting parts 2 are formed on both sides of the central part.
5 is formed, and an objective lens 2 is formed in the fitting opening T@22.
6 are fitted and glued together, and a focusing coil 27 wound into a rectangular tube shape is fitted and glued into the mounting recesses 25 on both sides. - Pair of tracking coils 28 are bonded.

The movable body 21 is mounted on the base 11 via a support mechanism 31 in the vertical focusing direction shown in FIG. 6 along the optical axis of the objective lens 26 and in the vertical direction shown in FIG. is supported so as to be movable in the tracking direction.

That is, the support structure 31 includes a support plate 32 made of synthetic Il resin.
The left end portions of a pair of upper and lower metal leaf springs 33 are planted in parallel on the right side of the figure, and the right end portions of the pair of upper and lower leaf springs 33 are connected to one end 35 of a synthetic resin hinge body 34 on the right side of the figure. A bendable thin hinge part 37 is formed between one end 35 of the hinge body 34 and the other end 36 on the left side in the figure, and a pair of upper and lower leaf springs 33
One end 35 of the hinge body 34 is elastically movable relative to the support plate 32 in the vertical focusing direction in FIG.
The other end 36 of the hinge body 34 is elastically movable relative to i35 in the vertical tracking direction in FIG.

The support mechanism 31 has the other end 3 of the hinge body 34.
6 is fitted and glued into the notch 24 of the movable body 21, and the pillars 16 of the base are fitted and glued into the pair of support holes 38 formed in the support plate 32, thereby moving the movable body 21 onto the base 11. , thereby supporting the movable body 2
1 in the upper and lower focusing directions in FIG. 6 and in the upper and lower tracking directions in FIG. 5.

Reference numeral 41 denotes a flexible printed wiring board. This printed wiring board 41 is used for the control RS signal line, and one end thereof is used as a terminal board and is glued to the outer surface of the support piece 15 of the base 11. and the other end is the base 11
It is adhered to the lower surface of the movable body 21 through the notch 13, and each terminal portion at the other end is connected to each of the coils 27 and 28.

Note that the support mechanism 31 allows the movable body 21 to be attached to the base 11.
The hinge part 37 of the hinge body 34 is located at the center of inertia of the movable parts such as the movable body 21, the objective lens 26, the focusing coil 21, the tracking coil 28, and the hinge body 34, and the hinge part at this center of inertia The focusing coil 27 and the tracking coil 28 on both sides are located symmetrically with respect to the coil 37.

Also, in this state, the inner corks 18 on both sides of the base 11
The corresponding focusing coil 2 of the movable body 21
7 surrounds the base 11, and the outer parts of the focusing coil 27 on both sides and the tracking coil 28 on the outer side of the focusing coil 27 surround the base 11.
The magnetic gap between the inner yoke 18 and the magnet 19 corresponds to each other.

With this configuration, this objective lens driving device uses the spherical seat 14 of the base 11 for positioning with respect to the mounting partner, and fixes the base 11 to the mounting partner.
In this state, similarly to a general objective lens drive device, control signals in each direction based on error detection in the focusing direction and the tracking direction are transmitted to the printed wiring board II.
1 to the focusing coil 27 and tracking coil 28 disposed in the magnetic gear V-tube between the magnet 19 and the inner yoke 1B. The objective lens 26 is integrally driven in the focusing direction and the tracking direction via the movable body 21, and by driving the objective lens 26, the base 11 is The laser beam passing through the through hole 12 is accurately focused on the signal recording surface of the information recording medium, and
This focused light spot is made to reliably follow the signal track on the signal recording surface.

(Problem to be Solved by the Invention) By the way, when manufacturing the objective lens drive and stomach described above, the operator assembles the base 11 side, the movable body 21 side, and the support mechanism 31 separately, and then assembles them. However, due to the accuracy of processing and molding of individual parts, errors during assembly, etc., the positional relationship between the objective lens 26 of the movable body 21 and the base 11 is not accurate, for example, as shown in FIG. The neutral position 1ff26N of the objective lens 26 in the tracking direction may not coincide with the center 148 of the spherical seat 14 of the base 11. If the neutral position 26N of the objective lens 26 deviates in this way, the following problems may occur. arise.

That is, to explain with reference to FIG. 9, the objective lens 2
6 is the neutral position 12 when performing the troughing operation.
For example, it moves within a range of about 0.5 degrees to both sides around 6N. At this point, the incident light entering the objective lens 26 must fill the effective beam diameter without being chipped within the effective beam diameter of the objective lens 26, no matter where the objective lens 26 moves. The center of this incident light is designed to coincide with the center 143 of the spherical seat 14 of the base 11 on the other side when the base 11 is mounted, but the center of this incident light is the neutral position M2 of the objective lens 26.
6N may deviate from the center 148 of the spherical seat 14 of the base 11, in order to prevent the incident light from missing within the effective beam diameter of the objective lens 26, the beam diameter LD of the incident light should be increased with a margin. This resulted in a decrease in the amount of light.

Furthermore, the center of the incident light, which is designed to coincide with the center 14S of the spherical seat 14 of the base 11, has the highest light m in the light intensity distribution within the light flux of the incident light, but the neutral position 1t26N of the objective lens 26 is the base. Center 143 of 11 spherical seats 14
If it deviates from this, a portion within the luminous flux diameter LD will be used, and a portion with a low light amount will be used, resulting in a decrease in efficiency and making it difficult to obtain a reliable signal.

The present invention has been made to solve such problems, and its purpose is to make the positional relationship between the objective lens of the movable body and the base accurate in the manufacture of the objective lens drive wJ equipment. It is something.

[Structure of the invention]

(Means for Solving the Problems) The present invention includes a movable body provided with an objective lens together with a focusing coil and a tracking coil, a base provided with a magnet and a yoke for the focusing coil and the tracking coil, and a movable body mounted on the base. a support mechanism that supports the movable body movably in a focusing direction along the optical axis of the objective lens and in a tracking direction intersecting the optical axis of the objective lens, and at least one of the focusing direction and the tracking direction of the movable body by the support mechanism. When manufacturing an objective lens drive device using a hinge body made of synthetic 11 resin that can be bent to support the
The hinge body made of synthetic wood is heated and aged with the movable body and the base positioned in a predetermined positional relationship.

(Function) The method for manufacturing an objective lens driving device of the present invention includes: with the movable body and the base positioned in a predetermined positional relationship;
By heating and aging the synthetic resin hinge body, the position DQ of the movable body, especially its objective lens and base.
This is for setting and correcting the settings accurately.

(Example) 'A' of the objective lens drive device described in FIGS. 5 to 7 for the method of manufacturing the objective lens drive device of the present invention? An example applied to i will be described.

Note that a detailed explanation of the objective lens driving device will be omitted as it has been explained previously.

1 and 2 show a state in which the base 11 and the movable body 21 are positioned using a jig 51 when manufacturing the objective lens [[v3] explained in FIGS. 5 to 7.

Here, in a separate process, the movable body 21 includes a focusing coil 27, a tracking coil 28, and a printing arrangement 12!, as shown in FIG. The plate 41 has been assembled, and the notch FJ524 of the movable body 21 in this state
Then, the other end i36 of the hinge body 34 of the support mechanism 31 is fitted and bonded, and the support mechanism 3 is attached to the support column 16 of the base 11.
The pair of support holes 38 of the support plate 32 of the first support plate 32 are fitted and adhered, and furthermore, a part of the printed circuit board 41 is adhered to the outer surface of the support piece 15 of the base 11, and the movable body 21
The notch 24 and the other part 3 of the hinge body 34 of the support mechanism 31
The base 11 and the movable body 21 are attached to the jig 51 by 5A before the adhesive between the base 11 and the movable body 21 is hardened.

The jig 51 has a positioning pin 52 that fits into the through hole 23 of the movable body 21 and a positioning seat 53 that fits into the spherical seat 14 that is concentric with the through hole 12 of the base 11. A positioning catch 53 is arranged concentrically, and a stepped portion 54 is formed on the positioning pin 52 to support the outer lower part of the through hole 23 of the movable body 21 . A magnet 55 is arranged to absorb and fix the spherical seat 14 portion of the movable body 21.
The through hole 12 of the base 11 can be positioned coaxially with the through hole 12 of the base 11, and the distance between the spherical surface Pi14 of the base 11 and the fitting recess 22 of the movable body 21 can be set. The positional relationship between the movable body 21 and the fitting recess 22 of the movable body 21 can be determined in the X direction, Y direction, and Z direction in FIG.

Then, using the jig 51, the base 11 and the movable body 2 are
1 is mechanically positioned as described above,
After curing the adhesive between the movable body 21 and the hinge body 34 of the support mechanism 31, the base 11, the movable body 21 and the support t
! 1$131 is placed in a heating furnace with ¥A attached to the jig 51, and heated and aged at a predetermined temperature for a predetermined time.
The hinge body 34 is corrected by aging, and then the objective lens 26 is fitted and bonded into the fitting recess 22 of the movable body 21.

The objective lens drive device manufactured in this way is manufactured using the jig 5.
1, the adhesive is cured with the through hole 12 of the base 11, the spherical seat 14, and the fitting recess 22 of the movable body 21 mechanically positioned.
By performing the aging step 4, the fitting recess 22 of the movable body 21, that is, the objective lens 26, the through hole 12 of the base 11, and the spherical seat 14 are Rank W1! I can correct the insanity of Section A.

Therefore, in the case of this objective lens driver vI device, if the spherical seat 14 of the base 11 is used for positioning with respect to the mounting partner, and the base 11 is fixed to the mounting partner, the objective lens 26 will be tracked as shown in FIG. The neutral position 1126N of the direction can be aligned with the center 143 of the spherical seat 14 of the base 11, and the beam diameter LD of the incident light can be adjusted to the actually used beam portion determined by the movement range of the objective lens 26.・As a result, it is possible to concentrate the luminous flux within a narrow luminous flux diameter LD, and it is possible to effectively use the incident light without causing a decrease in the light quantity, and moreover, it is possible to Since the use can be eliminated, a reliable signal can be obtained without reducing efficiency.

Note that in this embodiment, in the support mechanism 31, the movable body 2
1, that is, an objective lens drive device that uses a bendable synthetic resin hinge body 34 to support the objective lens 26 in the tracking direction, and the hinge body 34 is corrected by heat aging. However, the present invention is not limited to an objective lens drive vJ device that uses a bendable synthetic resin hinge body for support in the focusing direction, and this hinge body can be corrected by heat aging.

In addition, as a modified example, in FIG. 4, a clamper 6 is attached to the jig 51.
Poly the state with 1 added.

This clamp bar 61 is fitted to the jig 51. By fitting the clamp bar 61 to the jig 51 with the base 11 and the movable body 21 attached to the jig 51, the movable body is 21, thereby improving positioning accuracy.

〔Effect of the invention〕

As described above, according to the present invention, when manufacturing an objective lens drive device that movably supports a movable body provided with an objective lens on a base via a support structure including a synthetic resin hinge body, the movable body Since the synthetic resin hinge body is heated and aged with the base positioned at a predetermined position, the positional relationship between the movable body, especially the objective lens, and the base can be accurately set and corrected.
It is possible to manufacture an objective lens drive device with excellent characteristics, and
Variations in accuracy between products are eliminated, and the occurrence of defective products is reduced, so objective lens driving devices with excellent characteristics can be stably supplied at low cost.

[Brief explanation of the drawing]

1 to 4 show a method for manufacturing an objective lens driving device of the present invention, and FIG. 1 is a longitudinal cross-sectional view of the objective lens driving device being manufactured is attached to a jig used during aging; Fig. 2 is a perspective view of that state, Fig. 3 is a perspective view showing the assembled state of the movable body part before that, Fig. 4 is an exploded perspective view of a modified example in which a clamper is used together with a jig during aging, 5 to 7 show an objective lens driving device to which the present invention is applied, FIG. 5 is a plan view thereof, FIG. 6 is a sectional view thereof, FIG. 7 is a perspective view thereof, and FIG. 5 to 7 are schematic plan views of the objective lens driving device that do not show the problems that arise when the objective lens driving device shown in FIGS. FIG. 10 is an explanatory diagram illustrating in detail the effect when the objective lens drive device shown in FIGS. 5 to 7 is manufactured by the method of the present invention. 11... Base, 17.18φ Yoke, 19... Magnet, 21... Movable body, 2G... Objective lens, 21...
-Focusing coil, 28...Tracking coil, 31...Support Iav4.34...Hinge rest. July 18, 1988 Inventor: Hikaru Tamai
-Patent applicant: Toshiba Corporation 34th hinge body! Figure 2 Figure 5 Figure 6 Copper Figure 7 Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] (1) A movable body provided with an objective lens together with a focusing coil and a tracking coil; a base provided with a magnet and a yoke for the focusing coil and tracking coil; and a support mechanism movably supporting the movable body in the focusing direction and the tracking direction intersecting the optical axis of the objective lens. A method for manufacturing an objective lens drive device using a hinge body, the method comprising heating and aging the hinge body while the movable body and the base are positioned in a predetermined positional relationship. Production method.