JPS602632Y2 - Buzzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a buzzer in which a magnetic metal diaphragm is formed by magnetic interaction between an electromagnet and a permanent magnet provided to surround the electromagnet.

FIG. 1 shows a conventional example of this type of buzzer.

As shown in the figure, in the conventional buzzer, an iron core 2 wound with a coil 1 is erected on a disk-shaped yoke 3, and a cylindrical permanent magnet 4 is magnetically attracted to the outer peripheral edge of the yoke 3. Furthermore, since the structure was such that a ring-shaped spacer 5 and a magnetic metal diaphragm 6 with a weight 7 attached to the center were successively stacked on the open end 4a of the permanent magnet 4, there were the following drawbacks. .

(1) The vibration motion of the diaphragm 6 depends on the distance of the gap G1 formed between the diaphragm 6 and the tip surface of the iron core 2.
The distance of the gap G□ must be controlled to a constant value so that it does not vary depending on the individual buzzers.

However, with the structure shown in Fig. 1, the yoke 3,
Processing errors of the permanent magnet 4 and spacer 5, assembly errors due to adhesives on the contact surfaces of various parts, etc. are cumulative.
The position of the diaphragm 6 is not constant, and the distance of the gap G1 varies between individual buzzers, resulting in variations in sound quality and volume.

(2) For this reason, in the past, the iron core 2 was screwed onto the yoke 3 as shown in FIG. It was essential to set the value to a predetermined value.

However, the distance of the gap G1 is a small value of about 100±10 μ, and it is not necessarily easy to set the gap G1 to a predetermined value even if the above-mentioned adjusting means is used.

Moreover, with the above-described structure, the yoke 3, the iron core 2, or the permanent magnet 4 must be threaded, which increases the number of processing steps and increases costs.

(3) The permanent magnet 4, yoke 3, and iron core 2 must be manufactured individually by machining heavy magnetic metal materials, which increases the number of machining steps, and increases the overall weight and shape of the buzzer. Invites shape.

Since this type of buzzer is used by being incorporated into small devices such as pagers and temple meters, it must be made as light and compact as possible, and conventional buzzers are insufficient to meet this requirement. I can't respond.

(4) The buzzer shown in Figure 1 is normally used by being inserted into an outer case made of non-magnetic material such as synthetic resin.
A gap is likely to be formed between the outer surface of the permanent magnet 4 or yoke 3 made of a hard metal material and the outer case.

For this reason, a so-called one-beep sound occurs during the sound generation operation, resulting in poor vibration sound quality.

The present invention eliminates the above-mentioned drawbacks of the conventional technology and creates an inexpensive buzzer that can manage the air gap between the diaphragm and the iron core with high precision, and that is lightweight and small yet capable of producing a large volume of vibration sound. The purpose is to provide.

Distantly related to the above object, the present invention provides an electromagnet, a diaphragm facing the electromagnet through a gap, and a housing shaped like a cylinder with a bottom and having a support surface for supporting the diaphragm. case and
an iron core integrally erected on the bottom of the storage case; a baffle washer passing through the iron core and disposed on the inner surface of the bottom of the storage case; and surrounding the electromagnet on the washer. A buzzer having a permanent magnet arranged so as to
The permanent magnet is a rubber magnet or a resin magnet, and is tightly attached to the inner diameter of the storage case.

It is characterized by being inserted.

Hereinafter, the content of the present invention will be described in more detail with reference to the accompanying drawings, which are examples.

FIG. 2 shows a sectional view of the buzzer according to the present invention, and FIG. 3 shows an exploded view thereof.

In the figure, 8 is synthetic leather. A storage case made of non-magnetic material such as resin and shaped like a cylinder with a bottom.

The upper opening edge of the storage case 8 is provided with an annular step 8a.

9 is an iron core around which the coil 10 is wound.

The iron core 9 is integrally erected substantially on the axis of the bottom 8b of the storage case 8, and the position of its tip surface 9a is aligned with the step 8a.
The height is determined to be lower by a height G2.

Note that the storage case 8 and the iron core 9 are integrally molded, the details of which will be described later.

11 is a printed circuit board.

The printed circuit board 11 is shaped like a disk with a diameter slightly smaller than the inner diameter of the storage case 8, and has a center hole 1 provided in its center.
The iron core 9 is inserted through the housing 1a and placed on the bottom 8b of the storage case 8.

12 and 13 are lead terminals attached to the printed circuit board 11.

14 is a washer made of magnetic material.

The washer 14 is shaped like a disk with approximately the same diameter as the printed circuit board 11, and after inserting the iron core 9 into the storage case 8 through a central hole 14a provided in the center thereof, the printed circuit board 11 is inserted. It is stacked on top of 11.

Cutouts 14b to 14e are provided at the peripheral edge of the washer 14, so that the lead terminals 12.
This is a pretense of running away from 13.

The coil 10 of the iron core 9 is connected to a printed circuit board 11 and a washer 1.
4 is inserted into the storage case 8 and then wound around the iron core 9.

The lead wire of the coil 10 is guided toward the printed circuit board 11 through the notch 14b or 14d of the washer 14, passes through the cutouts R1lb, 11c, 11d, and 11e, and is wound around the printed circuit board 11, and then connected to the lead terminal 12. 13
Alternatively, it is soldered to a pattern on the printed circuit board 11.

15 is a cylindrical permanent magnet.

The permanent magnet 15 is fitted into the storage case 8 and placed on the washer 14 so as to surround the electromagnet formed by the iron core 9 and the coil 10.

The tip end surface 15a of the permanent magnet 15 is connected to the stepped portion 8a of the storage case 8.
The height is set to be lower by a height G3.

The permanent magnet 15 is constituted by a magnet made of an elastic magnetic material such as a rubber magnet or a resin magnet.

Rubber magnets, resin magnets, etc. are highly flexible and elastic, and even if they are made to have a diameter slightly larger than the inner diameter of the storage case 8, they can be easily pushed into the storage case 8, making assembly easier.

Furthermore, after insertion, the permanent magnet 15 comes into close contact with the inner circumferential surface of the storage case 8 due to its own elastic force without creating a gap, thereby preventing rattling noise and improving sound quality.

16 is a disk-shaped magnetic metal diaphragm.

The magnetic metal diaphragm 16 is supported by the stepped portion 8a of the storage case 8 as a support surface.

As mentioned above, the step portion 8a has a height G higher than the tip surface 9a of the iron core 9.
2, and is also higher than the tip surface 15a of the permanent magnet 15 by a height G3.

Therefore, when the magnetic metal diaphragm 16 is supported by the step portion 8a, there is a height difference between the lower surface of the magnetic metal diaphragm 16 and the tip surface 9a of the iron core 9 and the tip surface 15a of the permanent magnet 15. The corresponding air gap G2. G3 will be formed.

Due to the existence of the air gap G3, the air gap G2 between the tip surface 9a of the iron core 9 and the magnetic metal diaphragm 16 is caused by the gap G2 between the tip surface 9a of the iron core 9 and the support surface of the magnetic metal diaphragm 16 in the storage case 8, that is, the tip surface of the iron core 9 relative to the step portion 8a. It is determined only by the position of the printed circuit board 11, the washer 14, and the permanent magnet 1.
It is completely unrelated to the processing error in No. 5.

That is, in the buzzer according to the present invention, the distance of the gap G2, which is the most important in this type of buzzer, can be easily adjusted by simply managing the position of the tip end face 9a of the iron core 9 in a predetermined relationship with respect to the stepped portion 8a of the storage case 8. This means that it can be kept at a constant value.

The gap G2 can be easily made constant by integrally molding the storage case 8 and the iron core 9.

FIGS. 4A, B, C and D are concrete explanatory diagrams of mold forming.

In the figure, A is the male type and B is the female type.

The male type A is provided with a stepped portion 8'a corresponding to the stepped portion 8a of the storage case 8 on its outer periphery, and a recessed groove 9' into which the iron core 9 is inserted in the center thereof.

The axial distance between the bottom surface 9' of the groove 9' and the stepped portion 8'a is set to be approximately the same distance as the gap G2.

In addition, at the rear end of the core 9 to be inserted into the 9° groove,
A protrusion 9b is provided in a protruding manner, and a crushing margin is provided at the tip of the protrusion 9b to be crushed by a mold B, particularly a female die B.

That is, in FIG. 4A, the end faces a of the male mold A and the female mold B,
Let C' be the position of the bottom surface C of the female die B when they are in secure contact with each other. It is made to protrude in the direction of the female mold B by a length l beyond the position C', and this length l is used as the crushing margin.

Therefore, when the male die A and the female die B are pushed forward until their end surfaces a and b are pressed against each other with the iron core 9 inserted into the groove 9', the protrusion 9b of the iron core 9 will move into the groove 9°. Bottom surface 9'
Due to the pressing force applied between a and the bottom surface C of the female mold B, it is crushed only along its length (FIG. 4B).

In this case, since the position of the tip surface 9a of the iron core 9 coincides with the bottom surface 9'a, the position of the tip surface 9a is the same as that of the magnetic metal diaphragm 1.
A predetermined distance G2 is maintained with respect to the step portion 8'a corresponding to the support surface of No. 6.

Next, after injecting synthetic resin through the injection port d and molding (Fig. 4C), the male mold A and the female mold B are separated from each other, and the iron core 9 is integrally molded onto the bottom 8b of the storage case 8. This will result in a molded product with a high temperature.

(Figure 4D). According to the above-described molding, the position of the tip surface 9a of the iron core 9 with respect to the stepped portion 8a of the storage case 8, which serves as the supporting surface of the magnetic metal diaphragm 12, can be set within the error range determined by the mold. The air gap G2 can be managed with high precision.

Further, since a part of the protrusion 9b protruding from the iron core 9 is provided with a crushing margin, the machining error of the iron core 9 can be absorbed by this crushing margin.

Therefore, the machining accuracy of the iron core 9 may be relatively rough, and the machining cost can be significantly reduced.

By the way, this buzzer generates vibration sound by vibrating a magnetic metal diaphragm 16 through magnetic interaction between an AC electromagnet consisting of an iron core 9 and a coil 10 and a permanent magnet 15. Vibration plate 16 and permanent magnet 1
Magnetic circuit around 5 Ll, L! The magnetic resistance of the magnet is an extremely important factor in its performance.

In order to lower the magnetic resistance of the magnetic circuits Ll and L2 and improve performance, conventionally the iron core 2 and the permanent magnet 4 were mounted on the yoke 3 as explained in FIG. This resulted in various shortcomings.

In the present invention, the iron core 9 is inserted into a storage case 8 which is integrally molded with the iron core 9, and a washer 14 made of a magnetic material is fitted and inserted, and a permanent magnet 15 is placed on the washer 14.
This is provided.

With such a structure, the washer 14 is made independent from the storage case 8 and the iron core 9, thereby reducing the magnetic resistance of the magnetic circuits I, I, 2 and improving the performance of the buzzer while eliminating the influence on the air gap G2. I can do it.

Moreover, since the washer 14 is supported by the bottom part 8b of the storage case 8, it does not need to be thick and strong like the yoke 3 shown in FIG. 1, and can be easily obtained by pressing a thin plate material. .

Therefore, the processing itself becomes easier, and it also contributes to making the entire buzzer thinner.

Furthermore, when inserting into the storage case 8, the center hole 1
Assembling is very easy since it is only necessary to insert the iron core 9 through 4a.

As explained in detail above, the present invention provides a buzzer in which a magnetic metal diaphragm is vibrated by magnetic interaction between an electromagnet and a permanent magnet provided to surround the electromagnet. Since the non-magnetic storage case formed into a bottomed cylindrical shape with a supporting surface and the iron core of the electromagnet installed upright on the bottom of the storage case are integrally connected, (a) magnetic The gap accuracy between the metal diaphragm and the tip surface of the iron core is kept within the molding error range.

Therefore, a high-quality buzzer with extremely high gap accuracy is provided.

(0) It is possible to provide a low-cost buzzer with little variation in gap accuracy, constant high quality, and excellent mass productivity.

(c) An inexpensive buzzer that does not require a gap adjustment mechanism and is easy to handle is provided.

2) Since it is molded, it provides a small and lightweight buzzer with excellent mass productivity.

Furthermore, in addition to the above-mentioned components, (2) a washer made of a magnetic material through which the iron core is inserted is inserted into the storage case, and the permanent magnet is provided on the washer, (a) (1) above. This reduces the magnetic resistance of the magnetic circuit between the electromagnet and the permanent magnet without sacrificing the effectiveness of the system, thereby providing a buzzer with improved performance.

(b) By making the washer thinner, we will be able to provide a buzzer that is thinner overall.

(c) It provides a buzzer that is easy to process and easy to assemble.

(3) Since the permanent magnet is composed of a magnet made of an elastic magnetic material such as a rubber magnet or a resin magnet, it has high flexibility and elasticity, and even if the permanent magnet is manufactured with a diameter slightly larger than the inner diameter of the storage case, the storage case will not fit. It can be easily pushed inside, so
Assembly becomes easier.

Moreover, after insertion, the permanent magnet comes into close contact with the inner circumferential surface of the storage case due to its own elastic force without creating a gap, thereby preventing rattling noise and improving sound quality.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional buzzer, Fig. 2 is a cross-sectional view of a buzzer according to the present invention, Fig. 3 is an exploded view thereof, and Figs. 4 A-D are explanatory diagrams of mold forming according to the present invention. . 8...Storage case, 9...Iron core, 10
...Coil, 14...Washer, 15...
...Permanent magnet, 16...Magnetic metal diaphragm.

Claims (1)

[Scope of utility model registration request] an electromagnet; a diaphragm facing the electromagnet with an air gap;
A storage case formed into a cylindrical shape with a bottom and having a support surface for supporting the diaphragm, a pair of iron cores erected on the bottom of the storage case, and a pair of iron cores extending through the storage case. A buzzer has a magnetic washer disposed on the inner surface of the bottom of the buzzer, and a permanent magnet disposed on the washer so as to surround the electromagnet, the permanent magnet being a rubber magnet or a resin magnet. A buzzer characterized in that the buzzer is fitted tightly into the inner diameter of the storage case.