JPH0249220A - Coil manufacturing method for condensing lens drive device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing an electromagnetic coil for a drive device of a pickup of an optical storage device used in an external storage device of a computer or the like.

(Prior Art) Conventionally, as shown in FIG. 3, this type of optical pickup driving device has a focus coil 13 and a tracking coil 1 mounted on an objective lens holder 12 that holds an objective lens 11.
4 is attached, and these are slidably supported by a sliding shaft 16 and a bearing 17 attached perpendicularly to the body 15. 18 has the same weight as the objective lens 11, 4Jl.
! : It is the weight of. Permanent magnets are attached to the body so that the two coils 13 and 14 are placed in the magnetic field of the permanent magnet 19, and by passing current through the two coils 1:l and 14, an electromagnetic force is applied to the coils. acts to drive the objective lens 11.

Of the two coils, the focus coil 13 is wound in a plane perpendicular to the optical axis of the objective lens 11,
The other tracking coil 14 is wound in a plane parallel to the optical axis of the objective lens 11, and is also wound in a rectangular shape in order to make the first drive device thinner.

(Problem to be Solved by the Invention) - In the conventional method of winding a tracking coil in an optical pickup drive device, the diameter between the center of the winding and the outer periphery of the winding always changes during winding, resulting in a rectangular corner. In this section, a large amount of tension was applied to the wires, making it easy for them to break.

Furthermore, when attached to the objective lens holder with an adhesive, the rigidity is weak, and there is a drawback that unnecessary vibrations are imparted to the objective lens when the objective lens is driven.

An object of the present invention is to eliminate the drawbacks of the conventional wires, to provide high rigidity even when attached to an objective lens holder with an adhesive, without applying large tension to the wire during winding.

To provide an excellent method of manufacturing a coil for an optical pickup driving device that does not give unnecessary vibration to an objective lens even when the objective lens is driven.

(Means for Solving the Problems) A method for manufacturing a coil for a condensing lens driving device according to the present invention includes a lens for condensing convergent light onto an information recording medium, and the condensing lens is connected in a direction perpendicular to the information recording medium and in a direction perpendicular to the information recording medium. In a method for manufacturing an electromagnetic coil in a condensing lens drive device including an electromagnetic coil and a permanent magnet that are driven in a direction parallel to a recording medium,
After winding an electromagnetic coil in a ring shape, the coil is shaped by bending two arc parts facing each other with respect to the center of the ring perpendicular to the plane formed by the ring shape.

(Function) According to the present invention, cutting of the electric wire can be prevented by winding the tracking coil in a circular manner.
By bending the two opposing circular arc parts of the circular coil and sandwiching the objective lens holder between the circular arc parts, rigidity can be ensured and unnecessary vibrations of the objective lens that occur when driving the objective lens can be prevented.

(Example) An example of the present invention will be described based on FIGS. 1 and 2.

FIG. 1 is a perspective view showing the structure of an optical pickup driving device using an electromagnetic coil and a coil according to the manufacturing method of the present invention. In the figure, reference numeral 1 denotes an objective lens, which is held by an objective lens holder 2, and the objective lens holder 2 is a base 3.
It is slidably supported by a sliding member 11II4 and a bearing 5, which are mounted perpendicularly to the member. Furthermore, the objective lens holder 2 holds a weight 6 having the same weight as the objective lens 1 on the side opposite to the objective lens 1 with the sliding axis 4 as the axis of symmetry, and the side surface of the objective lens 1 is circularly wound. A focusing coil 7 is attached thereto, and a tracking coil 8 is further attached so as to sandwich the objective lens holder 2 and the focusing coil 7. A permanent magnet 9 is attached to the base 3, and the direction of the magnetic field generated by the permanent magnet is perpendicular to the winding direction of the focus coil 7 and the tracking coil 8.

FIGS. 2(a) and 2(b) show the tracking coil 8 of the present invention.
Fig. 2(a) shows the configuration of a tracking coil wound in a circular shape, and Fig. 2(b) shows a tracking coil whose opposing circular arcs are bent in the direction of the winding center axis. It is something.

Next, the operation will be explained. When current is applied to the focus coil 7, a force is applied to the focus coil 7 in the axial direction of the sliding shaft 4 due to the magnetic field of the permanent magnet 9, and the objective lens 1 moves in the axial direction of the sliding shaft 4 together with the objective lens holder 2. do.

Further, when a current is applied to the tracking coil 8, the magnetic field of the permanent magnet 9 causes the sliding shaft 4 to move from 1 to the tracking coil 8.
A force acts on the axis and in the rotation direction, and the objective lens 1 and the objective lens holder 2 rotate around the sliding shaft 4.

In this way, by passing current through the focus coil 7 and the tracking coil 8, the objective lens 1 can be rotated in the sliding axis 4 direction and around the sliding axis 4. At this time, the force acting on the focus coil 7 and the tracking coil 8 acts only in a part of the region where the magnetic field of the permanent magnet 9 acts perpendicularly to the winding direction of the two coils.
If the rigidity in this region is weak, unnecessary vibrations are likely to occur in the objective lens 1. However, by bending the opposing arcs of the circular tracking coil in FIG. 2(a) as shown in FIG. 2(b), the objective lens holder is This increases rigidity and prevents unnecessary vibrations from occurring in the objective lens.

(Effects of the Invention) According to the manufacturing method of the present invention, since the tracking coil is wound in a circle and then the opposing circular arcs are bent, the wire is less likely to break during winding, and the rigidity is increased, making it less likely that unnecessary vibrations will occur in the objective lens. , its practical effects are great.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a driving device for an optical pickup manufactured according to the present invention, and FIG. 2 is a perspective view of the tracking coil.
FIG. 3 is a perspective view of a conventional optical pickup driving device. 1...Objective lens, 2...Objective lens holder;
M... Base body, 4... Sliding shaft, 5... Bearing, (3
... Weight, 7... Focus coil, 8... Tracking coil, 8+i... Arc portion of tracking coil, 9... Permanent magnet. Patent applicant: Matsushita Electric P Co., Ltd. Figures (a) (b) 2-objective I /'

Claims (1)

[Claims] A condensing lens driving device comprising a lens for condensing focused light onto an information recording medium, and comprising an electromagnetic coil and a permanent magnet for driving the condensing lens in a direction perpendicular to the information recording medium and in a direction parallel to the information recording medium. A method for manufacturing an electromagnetic coil, wherein the electromagnetic coil is wound in a ring shape and then shaped by bending two arc parts facing each other with respect to the center of the ring shape perpendicular to the plane formed by the ring shape. A method of manufacturing a coil of the device.