JP2002199490A - Loudspeaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a loudspeaker, the assembling of which can easily be automated and the height of the product of which can be managed easily. SOLUTION: A magnetic circuit assembling case 1, consisting of a permanent magnet 13, a yoke 12, a top plate 14 and a lower cover 11, to which the yoke is imbedded, is welded with a 1st diaphragm assembling case 2, consisting of a diaphragm 22 fixed to an upper cover 21 and a voice coil 24 fixed to the diaphragm 22 for assembling the loudspeaker. The diaphragm 22 is joined with a face of the diaphragm assembling case 2, opposed to the magnetic circuit assembling case 1. A coil terminal 23a is led out along the diaphragm 22, tangled with a terminal 25a of a lead frame 25 imbedded in the upper cover 21 and is then fused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a speaker used for a mobile communication device or the like.

[0002]

2. Description of the Related Art In recent years, a thin and high-performance electrodynamic speaker has been widely used as an acoustic device of a mobile communication device such as a portable telephone. An example of such a conventional speaker will be described with reference to the drawings. FIG. 4 is a sectional view of a conventional electrodynamic speaker.

[0003] First, the configuration of this speaker will be described. In FIG. 4, reference numeral 51 denotes an annular case having an inner peripheral step 51a and an intermediate step 51b. Reference numeral 52 denotes a dish-shaped yoke with a flange 52a made of a magnetic material and embedded in the inner periphery of the case 51 as shown in detail in FIG. 53
Numeral denotes a disk-shaped permanent magnet fixed to the center of the inner surface of the yoke 2 and magnetized in the vertical direction. Numeral 54 denotes a disk-shaped top plate fixed to the upper surface of the permanent magnet 53. Permanent magnet 5
3, a magnetic circuit is formed through a gap between the upper end of the yoke 52 and the outer periphery of the top plate 54.

Reference numeral 55 denotes a substantially spherical diaphragm integrally formed of a plastic material having a flat portion 55a near the periphery and a curved portion following the flat portion 55a. It is adhesively fixed to the step 51b. Reference numeral 56 denotes a voice coil, which is a cylindrical air-core coil in which coil windings, which are enamel-coated copper wires, are wound in a rectangular cross section and solidified with paint, and the upper surface is bonded to the lower surface of the flat portion 55a of the diaphragm 55. Fixed. The voice coil 56 is fitted into a gap between the outer peripheral portion of the top plate 54 and the upper end portion of the yoke 52 at a depth of approximately half the coil length.
Reference numeral 57 denotes a protector whose peripheral portion is fixed to the intermediate step portion 51b of the frame 51. Reference numeral 58 denotes a lead frame provided on the lower surface of the case 51 and serving as an external connection terminal, to which a terminal 56a of the voice coil 56 is connected. In FIG. 6, reference numeral 59 denotes another example of a yoke with a flange 59a, and such a yoke 59 may be used.

Next, a method of assembling the speaker will be described. First, a surface on one magnetic pole side of the permanent magnet 53 is bonded to the center of the yoke 52, and then the top plate 54 is bonded and fixed with the center position aligned with the surface on the other magnetic pole side of the permanent magnet 53. On the other hand, the voice coil 56 is bonded to the flat portion 55a of the diaphragm 55. Next, the inner peripheral step 5 of the frame 51
1a and the voice coil 5 in the intermediate step 51b.
6 is adhered to the diaphragm 55 to which 6 is adhered. At this time, the coil terminal 56a is pulled out from the notch of the frame 51 (not shown) to the outer periphery, and the lead frame 5
8 by soldering or the like. Finally, the protector 57 is adhered on the diaphragm 55 to complete. When a voice signal is input to the voice coil 56 of the speaker, the diaphragm 55 vibrates up and down according to Fleming's left hand rule to emit sound.

[0006]

However, in the conventional speaker having such a configuration, since the yoke 52 has the flange 52a, it is necessary to cover the flange 52a with resin. For this reason, the frame 51c above the flange 52a has a raised shape, and the gap between the diaphragm through which the coil terminal 56a passes and the frame becomes narrow. As a result, the coil terminal 56 is
It was easy to come into contact with it, causing abnormal noise.

The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a speaker free of abnormal noise by securing a space around a coil terminal.

[0008]

According to one aspect of the present invention, there is provided a permanent magnet, a dish-shaped yoke fixed to one magnetic pole side of the permanent magnet, and In a speaker comprising a top plate fixed to the magnetic pole side, a resin frame in which the yoke is embedded, a diaphragm fixed to the frame, and a voice coil fixed to the diaphragm, a through hole or a hole is formed in a side wall of the yoke. A recess is formed, and the resin is filled in the through hole or the recess.

According to a second aspect of the present invention, in the first aspect of the invention, the resin filled in the through hole or the concave portion is a resin material for forming the frame. I do.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a speaker according to an embodiment of the present invention, FIG. 2 is a sectional view of a yoke of the speaker, and FIG. 3 is a sectional view of a yoke according to another embodiment.

First, the configuration of an electrodynamic loudspeaker according to an embodiment of the present invention will be described. In FIG. 1, reference numeral 1 denotes a frame formed of a resin material, and reference numeral 2 denotes a yoke buried in the center of the frame 1 without a flange portion, and details are shown in FIG. In FIG. 2, through holes are formed in, for example, four places on the side wall 2a of the yoke 2, and the through holes are filled with a resin material forming the frame 1. Reference numeral 3 denotes a disk-shaped permanent magnet magnetized in the vertical direction, and reference numeral 4 denotes a top plate bonded to the upper surface of the permanent magnet 3. Reference numeral 5 denotes a diaphragm having an outer peripheral edge adhered and fixed to the step portion 1b of the frame 1. Reference numeral 6 denotes a voice coil adhered and fixed to the lower surface of the diaphragm 5, and a coil winding which is an enamel-coated copper wire. This is an annular air-core coil that is arranged in a rectangular cross section and hardened with paint. Reference numeral 7 denotes a protector for preventing the diaphragm 5 from being damaged, and is fixed to the step 1b of the frame 1 from above the diaphragm 5. Reference numeral 8 denotes a pair of lead frames embedded in the frame 1, the ends of which are disposed so as to be exposed on the lower surface of the frame 1.

Next, in manufacturing the speaker of the present embodiment, when the yoke 2 is inserted to form the frame 1, a resin as a molding material is filled in the through hole 2b.
Therefore, the resin of the frame 1 near the yoke 2 does not need to be built up, and a sufficient space is secured between the resin and the diaphragm 5.

Next, the effect of this embodiment will be described. Since the yoke has a dish shape without a flange, and a through hole is formed in the side wall, the resin forming the frame can be filled into the through hole when embedding in the frame. A sufficient space could be secured, and as a result, the coil terminal could be prevented from contacting the frame. Further, the fixing force of the yoke can be sufficiently secured.

Instead of the yoke 2 described above, a yoke 12 as shown in FIG. 3 may be used. In the side wall 12a of the yoke 12, for example, four concave portions 12b are formed instead of the through holes. Since the resin forming the frame is filled in the concave portion 12b, the same effect as in the case of the through hole can be obtained.

[0015]

As described above, according to the present invention,
A through hole or a recess is formed in the side wall of the yoke of the speaker, and the through hole or the recess is filled with the frame resin. As a result, generation of abnormal noise due to contact of the coil terminal could be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a speaker according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a yoke of the speaker of FIG.

FIG. 3 is a cross-sectional view showing a yoke of a speaker according to another embodiment.

FIG. 4 is a cross-sectional view of a conventional speaker.

FIG. 5 is a partial sectional side view showing a yoke of a conventional speaker.

FIG. 6 is a partial sectional side view showing a yoke of a conventional speaker.

[Explanation of symbols]

 Reference Signs List 1 frame 2, 12 yoke 2a, 12a side wall 2b through hole 3 permanent magnet 4 top plate 5 diaphragm 6 voice coil 12b recess

Claims (2)

[Claims] 1. A permanent magnet, a dish-shaped yoke fixed to one magnetic pole side of the permanent magnet, a top plate fixed to the other magnetic pole side, a resin frame in which the yoke is embedded, and fixed to the frame A speaker comprising a vibrating plate and a voice coil fixed to the vibrating plate, wherein a through hole or a concave portion is formed in a side wall of the yoke, and the through hole or the concave portion is filled with a resin. 2. The resin filled in the through hole or the concave portion,
The speaker according to claim 1, wherein the frame is formed of a resin material.