JPS63160214A - Printed coil - Google Patents

Abstract

PURPOSE:To effectively prevent an insulating sheet from cracking due to foling, bending or heating and a conductor section from peeling by providing a dummy conductor at the sheet which does not form a coil so as to maintain the strength of the coil substantially uniform. CONSTITUTION:In order to maintain the strength of a whole coil 11 uniform, a plurality of dummy conductors 16 extended longitudinally are formed at insulating sheets 12 between coil sections 13a and 13b, between coil sections 13b and 13c, and between coil sections 13c and 13d. A plurality of dummy conductors 16 extended longitudinally are similarly formed at the sheet 12 inside the coil section together with the conductors 16. A plurality of dummy conductors 16 extended longitudinally and laterally are formed at the sheets 12 around connection sections 15a, 15b. The conductors 16 are formed on the same material as the section 13a-13d by etching or plating, etc. Thus, when the strength of the coil 11 is maintained substantially uniform, even if the sheet 12 is laterally bent, it can prevent the sheet from cracking.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printed coil suitable for use in a motor, an objective lens driving device for an optical pickup, and the like.

[Conventional technology]

For example, as an objective lens drive device in an optical pickup, Japanese Utility Model Application Publication No. 59-164938 discloses a printed coil 1 as shown in FIG. 4A as a drive coil, which is bent as shown in FIG. 4B to hold the objective lens. A device installed on the outer periphery of a holder has been proposed. This printed coil 1 consists of coils 38 to 3d made of copper formed by etching, plating, etc. on both sides of a flexible insulating sheet 2.
, through-hole portions 48 to 4d that connect the coil portions on both sides, respectively, and connection portions 5a and 5b to which lead wires for supplying current to the coil portions 38 to 3d are connected.

Such printed coils are extremely light in weight compared to coils made of windings of conductive wire, and therefore the weight of the moving parts can be reduced, allowing high-speed access and the pattern shape of each part to be made into various shapes. This has the advantage of increasing the degree of freedom in design.

[Problem that the invention seeks to solve]

However, in the conventional printed coil l described above, when the conductor part does not extend as shown in FIG. Cracks 6 occur in the insulating sheet 2 near the sections 48 to 4d, which may cause the coil section to break, or if another coil is wound on the printed coil 1, the other coil may break or break. There is a problem in that a short circuit with the printed coil occurs. Also,
When trying to solder external lead wires to the connecting parts 5a and 5b, since only the insulating sheet 2 surrounds these connecting parts 5a and 5b, the surrounding insulating sheet 2 expands due to the heat generated by soldering, and the stress is There is a problem that cracks occur or the connecting portions 5a and 5b lift up. Such a problem similarly occurs when the printed coil is attached to the rotor or stator of a motor.

This invention was made by focusing on such conventional problems, and even if it is bent or bent into an arbitrary shape, or even if heat is applied during soldering, etc., the insulating sheet will not crack or the conductor part will An object of the present invention is to provide a printed coil suitably configured to prevent lifting of the printed coil.

[Means for solving problems]

In order to achieve the above object, the present invention includes an insulating sheet, -
A dummy conductor is provided so that the strength is almost uniform in the part where the coil is not formed.

[For production]

In this way, by providing a dummy conductor to make the strength of the entire printed coil more or less uniform, even if the printed coil is bent or bent, or heated during soldering, etc.
The stress caused by the elongation and expansion acts almost uniformly on the entire printed coil, and does not act locally. Therefore, cracking of the insulating sheet and lifting of the conductor portion can be effectively prevented.

〔Example〕

FIG. 1 shows a first embodiment of the invention. This printed coil 11 is used by being bent or curved in the width direction like the one shown in FIG. Coil portions 13a to 13d made of a conductor such as copper formed by the above, through-hole portions 14a = 14d connecting the coil portions on both sides, and coil portions 13a to 13d.
13d is provided with connection parts 15a and 15b for connecting lead wires for supplying current, but in this embodiment, in order to make the strength of the entire printed coil 11 almost uniform, coil parts 13a and 13b are further connected. between coil parts 13b and 13c
A plurality of dummy conductors 1 extend in the longitudinal direction of the insulating sheet 12 between the coil parts 13c and 13d and between the coil parts 13c and 13d.
6, and a plurality of dummy conductors 16 extending in the length direction are similarly formed on the insulating sheet 12 inside each coil portion. In addition, connection parts 15a and 15b
A plurality of dummy conductors 16 extending in the length direction and the width direction are formed in the insulating sheath (12) around the insulating sheet (12). These dummy conductors 16 are formed of the same material at the same time as the coil portions 13a to 13d by etching, plating, etc.

In this way, if the strength of the entire printed coil 11 is made almost uniform by providing the dummy conductor 16, even if the insulating sheet 12 is folded in the width direction at each coil portion as shown in FIG. Since it is not locally concentrated, it is possible to effectively prevent the occurrence of cracks. Note that FIG. 2 shows a state in which the coil portion 13c is bent. Furthermore, even if the area around the lead wires is heated due to soldering of the lead wires to the connection parts 15a and 15b, the expansion in the surrounding area is suppressed by the interposition of the dummy conductor 16 compared to the case without this, so cracks due to expansion and connection Part 15
a.

Lifting of 15b can also be effectively prevented. Furthermore, if the dummy conductor 16 is provided in this way, the printed coil 11
Since the thickness of the coil can be made almost uniform, when a coil is wound on top of the coil, the coil can be wound uniformly without any disturbance.

FIG. 3 shows a second embodiment of the invention.

This printed coil 21 is basically different from the one shown in FIG. 1 in that the width of the flexible insulating seam 2 is partially narrowed, and the same reference numerals as shown in FIG. 1 have the same function. represents something that is made up of. In this way, when the width of the insulating sheet 12 is partially reduced, the strength of this part is weak, and stress due to bending or curving is concentrated in this part, making it easy to break. Therefore, in this embodiment, a dummy conductor 16 is formed in this narrow portion to reinforce the strength and thereby prevent concentration of stress. The printed coil 21 shown in FIG. 2 is attached to a holder that holds an objective lens in an objective lens drive device for an optical pickup, and the notch 22 is for positioning with the holder. Further, the holder is supported by four conductive wires so as to be movable in the focusing and tracking directions with respect to the fixed member. In addition to the connecting portions 15a and 15b with the connecting portions 13a to 13d, two additional connecting portions 15c and 15d are provided, and four wooden wires each having one end attached to a fixing member are attached to these four connecting portions 15a to 15d. By connecting the ends, the holder is movably supported relative to the fixed member. Here, the connection parts 15c and 15d are for wire connection and are not connected to the coil part, and power is supplied to the coil part through the connection part 15.
a, through the wire connected to 15b.

Although dummy conductors are not provided around the connecting parts 15a to 15d in this embodiment, since the width of the insulating sheet 12 is narrow in these parts, the surrounding area may be damaged by heating when soldering the wires. insulation sheet 12
There is almost no chance of cracking or lifting, so dummy conductors may not be provided.

In this embodiment, as in the case of FIG. 1, the strength of the entire printed coil 21 is substantially uniform, so that the same effect can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, a dummy conductor is provided on an insulating sheet that does not form a coil so that the strength of the printed coil is almost uniform. It is possible to effectively prevent the parts from lifting up. Therefore, it is possible to effectively prevent the occurrence of wire breakage, short circuit, etc. of the coil.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a first embodiment of the present invention, and FIG. 2 is a diagram showing a first embodiment of the present invention.
FIG. 3 is a diagram showing a second embodiment of the present invention, and FIGS. 4A and 4B are diagrams showing a conventional technique. 11...Printed coil 12...Insulating sheet 13
a to 13d... Coil portions 14a to 14d... Through hole portions 15a, 15b... Connection portion 16... Dummy conductor 21... Printed coils 15c, 15d...
Connection portion 22...notch Patent applicant Olympus Kyukogaku Kogyo Co., Ltd. Figure 1 Figure 3

Claims (1)

[Claims] 1. In a printed coil in which a conductor pattern is formed into a coil shape by etching or plating on a flexible insulating sheet, a dummy is installed so that the strength is almost uniform in the part of the insulating sheet where the coil is not formed. A printed coil characterized by the provision of a conductor.