JPH06267090A - Coil apparatus and coil assembly - Google Patents

Abstract

PURPOSE:To make a separate terminal plate unnecessary by forming (n) conductor patterns in the longitudinal direction of a flexible printed circuit board, winding the board by (m) turns of a coil, connecting both ends of the conductor patterns of different numbers, thereby forming the coil of nXm turns. CONSTITUTION:(n) conductor patterns 3 are formed on the surface of a flexible printed circuit board(FPC) 2. The FPC has upward projecting pieces 2A, 2B at both ends and an upward projecting piece 2C at the middle part thereof. The projecting piece 2A is provided with electrodes 7A, 7B, the projecting piece 2C with electrodes 4A, 4B, and the projecting piece 2B with lands 6a-6d, respectively. The FPC is wound (m) turns. The projecting piece 2B is bent outside, with the lands 6a-6d bonded to corresponding lands 5a-5d. Accordingly, (n) conductor patterns are connected as one coil, whereby a coil of nXm turns is formed. The terminal of the coil never protrudes outside, generating no possibility of a disconnection and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil device and a coil assembly, and more particularly to an optical head actuator which follows the focus and track directions of a rotating disk with high accuracy in order to detect signals from an optical disk or magneto-optical device. The present invention relates to an optimum coil device and coil assembly as a coil.

[0002]

2. Description of the Related Art A conventional optical head actuator (hereinafter also simply referred to as an actuator) has a structure as shown in FIG. In the figure, numeral 22 is a lens holder,
The objective lens 23 is provided at the tip, and the coil assembly 21 including the focusing coil 20A and the tracking coil 20B is housed in the central opening 22A.

Terminal plates 24, 24 are attached to both side walls, and the suspension wire 2 is attached to each terminal plate 24.
5, 25 are attached. The coil end from the coil assembly 21 is connected to the suspension wire 25 in each terminal plate 24 via the coil soldering portion 26 and the suspension wire soldering portion 27.

As shown in FIG. 6, the coil assembly 21 is formed by winding a self-bonding wire or the like around a pair of corners of a focusing coil 20A having a rectangular shape by winding a linear coil a plurality of times. The tracking coil 20B is formed by bending an L-shaped one into an L-shape, and both terminals 20a from the focusing coil 20A and both terminals 20b from the tracking coil 20B are drawn to the outside. The terminal is adapted to be soldered to the terminal board 24.

[0005]

According to the above-mentioned conventional apparatus, a total of four coil terminals, two from each coil for focusing and tracking, are drawn out from the coil assembly. There was a risk of breaking or cutting at some parts.

Further, since a terminal plate must be provided in order to connect the coil terminal and the suspension wire, there are problems such as an increase in the number of parts and a long working time.

The present invention solves the above problems, shortens the coil terminal lead-out length of each coil, and eliminates the need to individually provide a terminal plate for connection with an external device. It is intended to provide.

[0008]

The coil device of the present invention comprises:
N conductor patterns are formed along the longitudinal direction of a long flexible printed board, and the printed board is
A coil composed of n × m turns is formed by winding both ends and electrically connecting both ends of the conductive pattern in different orders, and the coil terminals are connected to the electrodes provided on the printed circuit board. It is characterized by that.

In the coil assembly of the present invention, n conductive patterns are formed along the longitudinal direction of a long flexible printed board, the printed board is wound m times, and both ends of the conductive pattern are formed. A first coil device in which a coil of n × m turns is formed by being electrically connected to each other in different orders, and a second coil device in which two rectangular coil members formed by winding a conductor are connected. Is arranged on the outer peripheral surface of the first coil device, and the coil lead electrode of each coil device is provided on the flexible printed board.

[0010]

According to the invention of claim 1, since the coil pattern and the coil terminal lead-out connection terminal are formed on the flexible printed circuit board, the coil terminal does not project to the outside.

Further, according to the invention of claim 2, any coil device is formed because the coil terminal lead-out connection terminal of the second coil device is also formed on the flexible printed board on which the first coil device is formed. Also, the coil end does not protrude outside.

Therefore, in any of the inventions, no breakage or breakage of the coil terminal is caused, and it is not necessary to provide a separate terminal plate for connection with an external device.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the coil device of the present invention. In this coil device 1, a plurality of (four in the figure) conductive patterns 3 along the longitudinal direction are formed on the surface of a long flexible printed circuit board (hereinafter sometimes abbreviated as FPC) 2, and this FPC 2 Upper protruding pieces 2A and 2B are formed at both ends of the upper protruding piece 2A, respectively, and the upper protruding pieces 2A and 2B are formed in the middle portion.
It is formed into a rectangular shape by winding a plurality of C-shaped ones and bonding them to each other. Land portions 5a, 5b, 5c, 5d are provided at one end of the conductive pattern, and the other end is provided on the tip projecting piece 2B and provided with land portions 6a, 6b, 6c, 6d. ing. In addition, the protruding piece 2C in the middle portion has a rectangular electrode 4 in the vertical direction.
A and 4B are formed, the uppermost conductive pattern 3a is extendedly connected to one electrode 4A, and the conductive pattern 3b extending from the land 5d is connected to the other electrode 4B. Further, the projecting piece 2A provided at the other end is also provided with two rectangular electrodes 7A and 7B in the vertical direction. Each of these electrodes 4A, 4B, 7A, 7B has a through-hole shape and is exposed on the front and back surfaces of each protruding piece 2A, 2C. Further, the protruding pieces 2A and 2C come to face each other in a state where the FPC is wound and formed, and the other protruding piece 2B is landed 6a when bent outward.
To 6d are set so as to come into contact with the lands 5a to 5d.

A land portion T for connecting another coil device is provided on the surface on which the land portions 5a to 5d are formed.
₁ is provided, and a conductive pattern 7a is formed on the land portion T ₁ so as to go around the back surface in the drawing along the surface and is connected to the electrode 7A of the protruding piece 2A. The land portion T ₁ is also formed on the electrode 7B. A conductive pattern 7b connecting between the _two is connected.

The coil device is completed by assembling the device having the above structure as shown in FIG. That is, the land portion 6
By bending and adhering the projecting pieces 2B to the outside so that the a to 6d contact at the corresponding positions of the lands 5a to 5d, a plurality of conductive patterns are connected and formed as one coil. Here, the conductive pattern along the longitudinal direction is n
When this is formed and wound m times, an n × m turn coil is formed.

The coil device constructed as described above may be used as a single coil, or may be used in combination with another coil device as described later. In any case, the coil end does not protrude outside,
Since it is in the state of being fixed to the substrate surface, it is possible to provide a highly reliable coil device in which there is no fear of breakage or disconnection.

Next, an embodiment of the coil assembly of the present invention will be described with reference to FIGS.

As shown in FIG. 3, this coil assembly 10 uses the above coil device 1 as a focusing coil.
The tracking coil 6 is combined with this. The tracking coil 6 includes two coil members 6A and 6B which are formed by winding a self-bonding electric wire or the like into an L shape and are bent into an L shape. Each of the bending parts is a pair of the focusing coil 1. The coil members 6A and 6B are connected and fixed so as to engage with the corners of the coil member 6A, and the terminal 6a of one coil member 6A is connected to the land portion T ₁ formed on one surface of the FPC 2 described above. , The end 6b of the other coil member 6B
Is connected to the land portion T ₂ formed on the other surface of the FPC 2 described above.

As a result, both ends 6 of the tracking coil 6 are
a and 6b are conductive patterns 7a and 7 formed on the FPC 2.
the electrodes 7A, 7 provided on the end projecting piece 2A through b.
B is connected to each.

Even in the above coil assembly, the end of the focusing coil is one protruding piece 2 of the FPC 2.
The C electrodes 4A and 4B are integrated, and the other end of the tracking coil is also integrated into the electrodes 7A and 7B of the protruding piece 2A, and neither coil terminal protrudes to the outside.

FIG. 4 is a perspective view showing a case where the coil assembly 10 is applied to an optical head actuator. Reference numeral 8 is a lens holder, which is provided with an objective lens 9 at its tip,
The coil assembly 10 is arranged in the central opening 8A. The coil assembly 10 is arranged by inserting the coil assembly 10 into the opening 8A, and then projecting pieces 2A and 2C at both ends.
May be fixed by adhesion or the like in a state of being bent outward along the frame portion of the lens holder 8. In this way, since the electrodes are located on both side surfaces of the lens holder 8,
A suspension wire (not shown) may be arranged at this portion and connected by soldering or the like.

According to such a device, there is no protruding coil terminal in either the focusing coil or the tracking coil, so that there is no fear of breakage or disconnection, and a highly reliable device can be obtained. Since it is not necessary to provide a separate terminal board for connection of, the number of parts can be reduced, the number of work steps can be reduced, and the cost and the size can be reduced.

The present invention is not limited to the above embodiment, and various modifications can be made.

For example, the coil assembly may be constructed as shown in FIG. This is one in which spiral coil patterns 16A and 16B are formed on a surface 12D corresponding to each of the protruding pieces 12A and 12C of the elongated FPC 12, and this is used as a tracking coil. With this configuration, the same effect as described above can be obtained, and in comparison with the embodiment of FIG.
Since the tracking coil has a pattern formed on the FPC surface, it is possible to further reduce the thickness and size. Further, there is an advantage that the work of connecting the coil terminals is also simplified.

In the embodiment, 4A, 4B, 7A, 7
B used the through-hole type, but the recently developed flexible wiring board with double-sided terminals (Nikkei Mechanical 1992.9.21 P108-P1
When 11) is used, since the terminals of the flexible printed circuit board are exposed on the front and back sides, pretreatment such as providing a through hole is unnecessary, and further simplification can be achieved.

[0027]

According to the present invention described in detail above, the following effects can be obtained.

According to the invention of claim 1, since the coil pattern and the coil terminal lead-out connection terminal are formed on the flexible printed circuit board, the coil terminal does not project to the outside.

According to the second aspect of the invention, any coil device is formed because the coil terminal lead-out connection terminal of the second coil device is also formed on the flexible printed circuit board on which the first coil device is formed. Also, the coil end does not protrude outside.

Therefore, in any of the inventions, no breakage or breakage of the coil terminal occurs, and it is not necessary to provide a separate terminal plate for connection with an external device.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a coil device of the present invention.

FIG. 2 is a perspective view showing an example of assembly of the coil device.

FIG. 3 is a perspective view showing an example of a coil assembly of the present invention.

FIG. 4 is a perspective view showing a case where the coil assembly is applied to an actuator.

FIG. 5 is a perspective view showing a configuration of a conventional actuator.

FIG. 6 is a perspective view showing a configuration of a conventional coil assembly.

FIG. 7 is a perspective view showing another example of the coil assembly of the present invention.

[Explanation of symbols]

 1 Coil Device 2 Flexible Printed Circuit Board 3 Conductor Pattern 4A, 4B, 7A, 7B Electrode 6 Tracking Coil 10 Coil Assembly

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] March 15, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Fig. 2]

[Procedure 3]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

[Procedure amendment 4]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

[Correction content]

[Figure 4]

[Procedure Amendment 5]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

[Figure 5]

[Procedure correction 6]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 6

[Correction method] Change

[Correction content]

[Figure 6]

[Procedure Amendment 7]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction content]

[Figure 7]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuto Nagano 1-13-1, Nihonbashi, Chuo-ku, Tokyo TDC Corporation

Claims (4)

[Claims] 1. A long flexible printed circuit board is formed with n conductor patterns along the longitudinal direction, the printed circuit board is wound m times, and both ends of the conductive pattern are electrically connected in different orders. The coil device is characterized in that an n × m turn coil is formed by being connected to the coil terminal, and the coil terminal is connected to an electrode provided on the printed board. 2. An n-shaped conductive pattern is formed along a longitudinal direction of a long flexible printed circuit board, the printed circuit board is wound m times, and both ends of the conductive pattern are electrically connected in different orders. The first coil device in which a coil of n × m turns is formed by being connected to the first coil device and the second coil device in which two rectangular coil members formed by winding a conductor are connected to each other are the first coil device. A coil assembly which is arranged on the outer peripheral surface of the coil device, and the coil lead-out electrode of each coil device is provided on the flexible printed board. 3. The coil assembly according to claim 2, wherein the first coil device is a focusing coil, and the second coil device is a tracking coil. 4. The coil assembly according to claim 3, wherein the coil member of the tracking coil is a spiral conductive pattern formed on the printed circuit board.