JPH10177389A - Electromagnetic sounding body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the rise of adhesive for fixing a diaphragm supporting ring while minimizing a structural change. SOLUTION: A circular groove 40a or the like is formed on the outer periphery of a diaphragm supporting ring 40 for supporting a diaphragm 42. Since the circular groove 40a or the like is formed, the advance of the adhesive for fixing the ring 40 is stopped by the groove 40a or the like even when the adhesive is raised through a gap between the outer periphery of the ring 40 and the inside wall of a case 36 by capillary phenomenon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic sounding body for generating sound by vibrating a diaphragm with an electromagnet, and more particularly to a structure for supporting a diaphragm with a diaphragm support ring.

[0002]

2. Description of the Related Art As a conventional electromagnetic sounding body of this kind, there is one having a structure shown in FIG. This electromagnetic sounding body is of a surface mount type mounted on the surface of a circuit board by reflow soldering or the like. An electromagnet is placed in a box-shaped case 6 formed by joining the upper case 2 and the lower case 4. 8,
In this case, the diaphragm supporting ring 10 and the diaphragm 12 were housed.

The electromagnet 8 includes a yoke 14, a coil 16 having terminals connected to external terminals 18 and 20 attached to the yoke 14 and drawn out of the case 6.
And a magnet 22 provided therearound. Further, the diaphragm supporting ring 10 is disposed outside the magnet 22, and the outer peripheral surface and the lower surface thereof are fixed by being bonded to the inner wall of the case 6 and the yoke 14, respectively. Further, the diaphragm 1
No. 2 was supported in a vibrable state by placing the outer peripheral portion on the diaphragm supporting ring 10.

[0004]

In the conventional electromagnetic sounding body having the above-described structure, when the diaphragm supporting ring 10 is bonded, the adhesive is applied to the diaphragm supporting ring 10 by capillary action.
The upper part of the diaphragm support ring 10 rises in the gap between the case and the case 6, and the diaphragm 12 placed thereon is fixed to the diaphragm support ring 10 and the case 6. Was. When the diaphragm 12 is fixed as described above, the vibration is suppressed, and there is a problem that a generated sound is reduced. Such an increase in the adhesive due to the capillary phenomenon may also occur when the adhesive for fixing the diaphragm support ring 10 is melted by the heat of the reflow solder during surface mounting, and improvement is desired. Was.

In order to solve the above-mentioned problems, if the gap between the diaphragm supporting ring 10 and the inner wall of the case 6 is widened, the case 6 becomes larger, or the diaphragm supporting ring 10 becomes larger.
At the same time, it is necessary to reduce the diameter of the diaphragm 12 or to change the fixing structure of the diaphragm support ring 10 to a more complicated structure, which causes a new problem in terms of incorporation into a circuit board, volume and cost. That was to be expected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to suppress the rise of the adhesive for fixing the diaphragm support ring while minimizing structural changes. To provide a sounding body.

[0007]

An electromagnetic sounding body according to the present invention comprises:
An electromagnetic sounding body that generates sound by vibrating a diaphragm supported by a diaphragm support ring with an electromagnet, wherein an annular groove, unevenness, or a concave or convex portion is provided on an outer peripheral surface of the diaphragm support ring. .

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the electromagnetic sounding body of the present invention, an outer peripheral surface of a diaphragm supporting ring for supporting a diaphragm has an annular groove formed along the outer periphery thereof, and fine irregularities formed by honing. Alternatively, a plurality of concave portions or convex portions are provided. By providing the annular groove, etc., even if the adhesive for fixing the diaphragm support ring starts to rise in the gap between the outer peripheral surface of the diaphragm support ring and the inner side wall of the case due to the capillary phenomenon, the adhesive is formed. The agent stops accumulating due to the action of accumulating in the annular groove or the like, and does not rise until reaching the diaphragm.

[0009]

1 is a sectional view showing the structure of an electromagnetic sounding body according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of a diaphragm supporting ring, and FIG. 3 is a perspective view thereof.

This electromagnetic sounding body has basically the same structure as the above-mentioned conventional electromagnetic sounding body. That is, the electromagnetic sounding body of the present embodiment has a box-shaped case 36 formed by joining the upper case 32 and the lower case 34.
And an electromagnet 38, a diaphragm support ring 40, and a diaphragm 42 housed therein. The electromagnet 38 includes a yoke 44 composed of a plate portion 44a and a bar portion 44b erected at the center thereof, and external terminals 48, 50 attached to the outer periphery of the bar portion 44b and drawn out of the case 36. Coil 4 with terminal connected to
6 and a ring or C attached to the plate-like portion 44a of the yoke 44 at a certain interval outside the coil 46.
And a magnet 52 having a shape.

On the other hand, the diaphragm support ring 40 is made of metal, heat-resistant plastic, or the like, and its outer peripheral surface has
An annular groove 40a, which is a feature of the present invention, is provided. The annular groove 40a is formed by performing automatic lathe processing or the like along the outer periphery of the diaphragm support ring 40. In the present embodiment, a plurality of annular grooves 40a are arranged in the height direction. Is formed. This diaphragm support ring 4
The inner diameter and the outer diameter of 0 are set so that they can be fixed to the outside of the magnet 52 at a fixed interval and fixed to the inner wall of the case 36 with an adhesive. In addition, the diaphragm 42
The diaphragm support ring 4 is opposed to the electromagnet 38.
The outer peripheral portion is placed on the reference numeral 0, and is positioned by being attracted by the magnet 52.

In the electromagnetic sounding body according to the present embodiment having the above-described structure, the corner portion 40 on the lower periphery of the diaphragm support ring 40 is provided.
After the adhesive has been applied to the entire periphery of the upper surface of the plate-shaped portion 44a of the yoke 44 with which the b contacts, or the entire periphery of the lower portion of the inner wall of the lower case 34, the diaphragm support ring 40 is moved to the lower case 34.
Will be incorporated within. Thereby, the diaphragm support ring 40
Has its lower surface bonded to the plate-like portion 44a of the yoke 44,
The outer peripheral surface is bonded to the inner side wall of the lower case 34. afterwards,
The diaphragm 42 is placed on the diaphragm support ring 40, and the upper case 32 is joined to the lower case 34. in this way,
When the diaphragm support ring 40 is incorporated into the lower case 34 and when the upper case 32 is joined to the lower case 34, the adhesive spreads into the gap between the diaphragm support ring 40 and the case 36 by capillary action. . However, in the present embodiment, when the adhesive reaches the annular groove 40a, it will accumulate here. For this reason, the progress of the adhesive stops, and the adhesive does not rise and reach the diaphragm 42. Similarly, when the adhesive for fixing the diaphragm support ring 40 is melted by heat of the reflow solder or the like,
The melted adhesive stops rising at the annular groove 40a, and does not reach the diaphragm 42.

As described above, the annular groove 40a is for stopping the progress of the adhesive due to the capillary phenomenon.
It is desirable to increase the width of the groove so that the progress can be stopped, and to form a plurality of grooves as shown in FIG.

The annular groove 40a may have a V-shaped cross section as shown in FIG.
In addition, depending on the processing method, as shown in FIG.
It may be formed in a U-shape as shown in FIG. 5, or in a stepped shape as shown in FIG. Further, the position where the annular groove 40a is formed may be formed over the entire area in the height direction of the outer periphery as shown in FIG. 2, or one or several lines may be formed above the outer periphery as shown in FIG. Then, the rise of the adhesive may be surely prevented before the diaphragm 42.

FIG. 8 is a side view showing a modification of the diaphragm supporting ring 40 of the electromagnetic sounding body shown in FIG. On the outer peripheral surface of the diaphragm support ring 40, fine irregularities 40
c is formed, and it is a so-called Rishiji outer shape. The fine irregularities 40c are formed by honing or the like. Thus, the diaphragm support ring 40
By providing the fine irregularities 40c on the outer peripheral surface of the substrate, the resistance between the outer peripheral surface of the diaphragm support ring 40 and the adhesive increases, and the rise of the adhesive due to the capillary phenomenon can be prevented. Incidentally, even if the unevenness 40c is relatively large, a pool of the adhesive can be formed, so that the rise of the adhesive can be similarly prevented. When the diaphragm supporting ring 40 is formed of plastic, the unevenness 40c can be formed at the time of molding.

FIGS. 9 and 10 are sectional views showing another modification of the diaphragm support ring 40 of the electromagnetic sounding body shown in FIG. A plurality of concave portions 40d or convex portions 40e are formed on the entire outer peripheral surface of the diaphragm supporting ring 40.
By forming the concave portion 40d or the convex portion 40e in this manner, the adhesive rising due to the capillary phenomenon can be accumulated in the concave portion 40d or between the inner wall of the case 36 and the surface around the convex portion 40e. The rise of the agent can be prevented.

[0017]

According to the present invention, since the annular groove or the like is provided on the outer periphery of the diaphragm supporting ring, the adhesive for fixing the diaphragm supporting ring is moved in the gap between the diaphragm supporting ring and the case. It is possible to prevent the diaphragm from rising, and prevent the diaphragm from being fixed by the rising adhesive. For this reason, a highly reliable electromagnetic sounding body can be provided.

Further, since there is no need to change the shape, size, structure, and the like, a new problem and an increase in cost due to the change in structure are not caused.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of an electromagnetic sounding body according to one embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the diaphragm support ring shown in FIG.

FIG. 3 is a perspective view of a diaphragm support ring shown in FIG. 2;

FIG. 4 is a sectional view showing another sectional shape of the annular groove shown in FIG. 2;

FIG. 5 is a sectional view showing another sectional shape of the annular groove shown in FIG. 2;

FIG. 6 is a sectional view showing another sectional shape of the annular groove shown in FIG. 2;

FIG. 7 is a cross-sectional view showing another example of the formation position of the annular groove shown in FIG.

FIG. 8 is a side view showing a modified example of the diaphragm support ring of the electromagnetic sounding body shown in FIG.

FIG. 9 is a sectional view showing another modification of the diaphragm support ring of the electromagnetic sounding body shown in FIG. 1;

FIG. 10 is a sectional view showing another modification of the diaphragm support ring of the electromagnetic sounding body shown in FIG. 1;

FIG. 11 is a sectional view showing the structure of a conventional electromagnetic sounding body.

[Explanation of symbols]

 6, 36 case 8, 38 electromagnet 10, 40 diaphragm support ring 12, 42 diaphragm 40a annular groove 40c irregularity 40d concave part 40d convex part

Claims (5)

[Claims] 1. An electromagnetic sounding body for generating sound by vibrating a diaphragm supported by a diaphragm support ring with an electromagnet, wherein an annular groove is provided on an outer peripheral surface of the diaphragm support ring. Pronunciation body. 2. The electromagnetic sounding body according to claim 1, wherein a plurality of said annular grooves are provided. 3. An electromagnetic sounding body that generates sound by vibrating a diaphragm supported by a diaphragm support ring with an electromagnet, wherein irregularities are formed on the entire outer peripheral surface of the diaphragm support ring. Electromagnetic sounding body. 4. The electromagnetic sounding body according to claim 3, wherein the unevenness is finely formed by honing. 5. An electromagnetic sounding body for generating sound by vibrating a diaphragm supported by a diaphragm support ring with an electromagnet, wherein a plurality of recesses or protrusions are formed on the entire outer peripheral surface of the diaphragm support ring. An electromagnetic sounding body characterized in that: