JPH04341100A - Microspeaker - Google Patents

Abstract

PURPOSE:To obtain the reliable microspeaker without disconnection fault at a low cost by reducing tension to be generated on a voice coil lead wire due to the displacement of a diaphragm in the microspeaker used for various acoustic and video equipments and information and communications equipments. CONSTITUTION:A lead wire 12a pulled out from a voice coil 12 located 2 to 3mm apart from the drawing part 12b is adhered to the outer peripheral part of the voice coil using flexible adhesive 18. Accordingly, the tension on the voice coil lead wire 12a is reduced and the disconnection fault can be prevented.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to micro speakers used in various audio and video equipment, information and communication equipment.

0002

2. Description of the Related Art In recent years, there has been an increase in the need for miniaturization and portability of various electronic devices, and small-diameter, thin micro-speakers have been widely used as sound-producing devices.

[0003] A conventional micro speaker will be explained below. FIG. 3 shows the configuration of a conventional micro speaker. FIG. 4 is a perspective view of the voice coil section of the micro speaker. 3 and 4, the cylindrical voice coil 2 is fixed approximately at the center of the diaphragm 1, and the upper plate 3,
A static magnetic field is applied to the voice coil 2 by a magnetic circuit consisting of a yoke 4 and a magnet 5, and a signal current is caused to flow through the voice coil 2, thereby producing sound based on the electrodynamic conversion principle.

In the above configuration, conventionally the voice coil 2
The lead wires 2a are fixed to the surface of the diaphragm 1 on the magnetic circuit side, or are drawn out through the space between the diaphragm 1 and the frame 7 and connected to the terminal plate 6.

[0005]

However, in the conventional configuration described above, tension is applied to the lead wire 2a of the voice coil 2 due to the displacement of the diaphragm 1 during operation, and normally the lead wire 2a of the voice coil 2 has a diameter of 0. .03mm~0.
Since it is composed of 0.08 mm thin wire, there is a risk of wire breakage.

[0006]Also, in order to reduce the above-mentioned tension, there is a conventional example in which slack is provided in part or the whole of the lead wire 2a of the voice coil 2 during manufacturing, but this increases the manufacturing cost and also reduces the stability of the lead wire 2a. It was difficult to pick up the slack.

The present invention solves the above-mentioned conventional problems, and by reducing the tension generated in the voice coil lead wire due to the displacement of the diaphragm, it is possible to create a highly reliable micro speaker without the risk of wire breakage. The aim is to provide it at a low price.

[0008]

[Means for Solving the Problems] In order to achieve this object, the microspeaker of the present invention has a lead wire drawn out from the voice coil that is soft-bonded to the outer periphery of the voice coil with a flexible adhesive near the lead-out portion. The voice coil lead wire is drawn out through the space between the diaphragm and the frame and connected to the terminal plate.

[0009]

[Operation] With this configuration, even if tension is applied to the voice coil lead wire due to displacement of the diaphragm during operation, the flexible adhesive deforms to reduce this tension and avoid the risk of wire breakage. can.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show the configuration of a micro speaker in an embodiment of the present invention. Figure 1
, In FIG. 2, 12 is a cylindrical air-core voice coil, and the difference from the conventional configuration is that the lead wire 12 is drawn out.
a is soft-bonded to the outer periphery of the voice coil body using a flexible adhesive 18 at a position 2 to 3 mm away from the pull-out portion 12b. 11 is a diaphragm, and the voice coil 12 is fixed approximately at the center thereof. In addition, diaphragm 1
1, a magnetic circuit having an annular magnetic gap 19 is formed by an upper plate 13, a yoke 14, and a magnet 15. This magnetic circuit is held by a frame 17, and the voice coil 12 is in contact with the upper plate 13 and the yoke 14. It is held so that it fits within the magnetic gap 19 without any distortion. A lead wire 12a of the voice coil 12 is led out through a space between the diaphragm 11 and the frame 17, and is connected to a terminal plate 16 provided on the frame 17.

In this embodiment, a silicone adhesive is used as the flexible adhesive 18, and the soft adhesive part is attached from the upper end of the voice coil 12 so as not to come into contact with the adhesive between the voice coil 12 and the diaphragm 11. They are separated by about 1mm.

The operation of the micro speaker configured as described above will be explained below. Voice coil 12
By passing a signal current through the magnetic gap 19, the voice coil 12 vibrates and generates sound according to the generally known electrodynamic conversion principle due to the action of the static magnetic field in the magnetic gap 19, but the terminal end of the lead wire 12a of the voice coil 12 is fixed. Therefore, when the voice coil 12 is displaced up and down, the lead wire 12a of the voice coil 12 tends to tighten. However, in the configuration of this embodiment, the flexible adhesive 18 deforms to absorb distance changes, and the tension or tension on the lead wire 12a of the voice coil 12 is reduced.

As described above, according to this embodiment, the lead wire 12a drawn out from the voice coil 12 is attached to the outer periphery of the main body of the voice coil 12 with the flexible adhesive 18 at a position 2 to 3 mm away from the lead wire 12b. By soft bonding, the tension acting on the lead wire 12a of the voice coil 12 can be reduced and the risk of wire breakage can be avoided. Further, it can be easily realized by performing additional processing on a single voice coil, and has no effect on the assembly process, so it has the advantage that it can be implemented at low cost.

[0014] In this embodiment, an internal magnetic type magnetic circuit configuration is used, but it goes without saying that an external magnetic type configuration may also be used. Furthermore, although an air-core voice coil is used in this embodiment, a voice coil with a bobbin may be used.

[0015]

Effects of the Invention As described above, the present invention allows the lead wire drawn out from the voice coil to be soft-bonded to the outer periphery of the voice coil with a flexible adhesive near the lead-out portion, and the voice coil lead wire to be attached to the diaphragm. By drawing it out through the space between the frames, an excellent micro speaker without the risk of wire breakage can be realized at low cost.

[Brief explanation of drawings]

[Fig. 1] Cross-sectional view of a micro speaker in one embodiment of the present invention

[Figure 2] A perspective view of the voice coil of the micro speaker in the same example.

[Figure 3] Cross-sectional view of a conventional micro speaker

[Figure 4] Perspective view of the voice coil of a conventional micro speaker

[Explanation of symbols]

11 Diaphragm 12 Voice coil 12a Voice coil lead wire 12b Voice coil lead wire pull-out portion 13 Upper plate 14 Yoke 15 Magnet 16 Terminal plate 17 Frame 18 Flexible adhesive 19 Magnetic gap

Claims (1)

[Claims] Claim 1: A lead wire drawn out from the voice coil is softly bonded to the outer periphery of the voice coil with a flexible adhesive near the lead-out portion, and the voice coil lead wire is passed through the space between the diaphragm and the frame to the outside. A micro speaker characterized by being connected to a drawer and a terminal board.