JPS5855747Y2 - Buzzer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a buzzer that generates vibration sound by vibrating a metal diaphragm through the interaction of an alternating magnetic field and a direct current magnetic field.

As a conventional buzzer of this type, the one shown in FIG. 1 is known.

That is, in the conventional buzzer, an iron core 2 wound with a coil 1 is placed upright on a disk-shaped yoke 3, and a cylindrical permanent magnet 4 is magnetically attracted to the outer peripheral edge of the yoke 3. The structure was such that a magnetic metal diaphragm 6 was mounted and attracted to the open end 4a of the permanent magnet 4 via a ring-shaped spacer 5.

The advantage of this type of buzzer is that since the permanent magnet 4 applies a direct current magnetic bias to the diaphragm 6, it is possible to generate a sufficiently loud vibration sound just by passing a small current through the coil 1. Since the structure is such that the vibration sound is generated only by the vibration of the diaphragm 6 itself, rather than by colliding with the members of be.

However, the cylindrical permanent magnet 4, yoke 3, etc., which are essential components of this buzzer, must be made of heavy magnetic metal materials, which inevitably increases the weight and shape of the entire buzzer. There are drawbacks.

In particular, this type of buzzer is used by being incorporated into pagers, watches, etc., so it has to be as lightweight as possible.
This demand for weight reduction cannot be fully met.

Moreover, with the above configuration, each component must be individually machined and manufactured, resulting in a large number of parts.
There were also disadvantages of increased man-hours and rising costs.

Furthermore, the heart of this buzzer is the metal diaphragm.
Although the metal diaphragm is supported by rigid permanent magnets, yokes, etc. that have no elastic cushioning properties, the metal diaphragm is easily deformed by external shocks, and there is a risk that performance may be impaired.

It is an object of the present invention to provide an inexpensive buzzer that can be significantly reduced in weight, is easy to manufacture, and retains the above-mentioned advantages of this type of buzzer.

Another object of the present invention is to provide a highly reliable buzzer that can effectively protect the metal moving plate from external impact.

Still another object of the present invention is to provide a buzzer that can absorb especially harmonic distortion and generate high-quality vibration sounds during sound generation.

The above-mentioned object of the present invention is to provide a buzzer in which a metal diaphragm is vibrated by the interaction of an alternating magnetic field and a direct current magnetic field to generate vibration sound, in which the direct current magnetic field is placed around an iron core with a coil that generates the alternating magnetic field. A ring-shaped rubber magnet is provided to generate the vibration, and the metal diaphragm is supported by the rubber magnet.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The content of the present invention will be described in detail below with reference to the accompanying drawings, which are examples.

FIG. 2 shows a sectional view of the buzzer according to the present invention.

In the figure, 7 is an iron core around which a coil 7a is wound.

A male screw portion 7b is provided at the lower end of the iron core 7, and by screwing this screw portion 7b into a female screw portion 8 provided on the axis of a flat base 8, the iron core 7 can be rotated. It is erected on the base 8.

The base 8 may be made of either magnetic or non-magnetic material.

Reference numeral 9 denotes a ring-shaped rubber magnet, which is arranged coaxially around the iron core 7.

When the base 8 is made of a magnetic material, the rubber magnet 9 is magnetically attracted to the base 8, so there is no need for a separate connection mechanism between the two.

On the other hand, when the base 8 is made of a non-magnetic material such as plastic, the rubber magnet 9 can be attached to the base 8 using an adhesive or the like.

As shown in the figure, the rubber magnet 9 has magnetic poles N or S formed at both ends in the axial direction.

Reference numeral 10 denotes a magnetic metal diaphragm, which is supported by being magnetically attracted to the upper end of the rubber magnet 9.

Since the rubber magnet 9 protrudes upward from the tip of the iron core 7, a gap G equal to the length of the protrusion is formed between the metal diaphragm 10 and the iron core 7.

This gap G can be adjusted by rotating the iron core 7 to the right or left and adjusting the amount of screw engagement.

In the buzzer of the present invention having the above configuration, when one alternating current is passed through the coil 7a, the metal diaphragm 10 moves up and down due to the interaction between the alternating magnetic field generated in the iron core 7 and the DC bias magnetic field generated by the rubber magnet 9. It vibrates in the direction (in the figure) and generates vibration sound.

The vibration sound at this time depends only on the vibration of the metal diaphragm 10, and does not include collision sound.

Therefore, it is possible to obtain a vibration sound with less distortion and a good texture.

Furthermore, since the buzzer according to the present invention has a rubber magnet 9 as the magnet for direct current magnetic field, its weight can be significantly reduced compared to the conventional buzzer shown in FIG.

At the same time, it can be easily manufactured by punching, and the product cost can be reduced.

Furthermore, since the metal diaphragm 10 is supported by the rubber magnet 9, the rubber magnet 9 acts as a buffer against external forces such as impact force applied to the metal diaphragm 10, and the metal diaphragm 10 is effectively protected against external forces such as impact. can be protected.

At the same time, the rubber magnet 9 acts as an acoustic damper material,
It can absorb harmonic distortion contained in vibration sound and emit high-quality vibration sound.

FIG. 3 shows a sectional view of another embodiment of the buzzer according to the present invention.

In the figures, the same or similar reference numbers as in FIG. 2 indicate the same or similar components.

8' is a cylindrical body with a bottom that supports the rubber magnet 9'.

The bottomed cylindrical body 8' has an iron core 7' on the axis of its bottom B'a.
At the same time, an annular step 8'b is formed on the inner periphery of the iron core 7', and this step 8'b
A rubber magnet 9' is fitted therein.

Although the rubber magnet 9' is highly flexible and elastic, the stepped portion 8'b
Even if the diameter is slightly larger than the inner diameter of the step part 8'b, it can be easily fitted and inserted into the step part 8'b, and after insertion, the step part 8'
It comes into close contact with the inner circumferential surface of b.

As a result, in this embodiment, the rubber magnet 9' and the bottomed cylinder 8
Since it is possible to avoid creating a gap between
This prevents the so-called rattling sound from occurring and improves the sound quality.

Note that the bottomed cylindrical body 8' does not need to function as a yoke.

Therefore, it is possible to integrally mold it using a non-magnetic material such as plastic.

When integrally molded, it can be made as thin and light as possible while taking mechanical strength into consideration.

12' is a clamping body that also serves as an acoustic housing.

The cylindrical lower end of the clamping body 12' is screwed into a threaded part carved into the inner periphery of the upper opening of the bottomed cylinder 8', and at this time, the lower end surface presses the metal diaphragm 10'. It is designed to be fixed.

In this case, since the rubber magnet 9' acts as a packing, the metal diaphragm 10' is securely press-fitted inside the bottomed cylindrical body 8' while protecting the metal diaphragm 10' from the clamping force, thereby reducing the sound pressure level of the vibration sound. The frequency can be stabilized.

Furthermore, the rubber magnet 9' can be expanded and contracted by adjusting the amount of screwing of the clamping body 12' into the bottomed cylinder 8'.

Since the supporting position of the magnetic metal diaphragm 10' moves up and down in accordance with the expansion and contraction of the rubber magnet 9', the magnetic metal diaphragm 1
0' and the tip surface of the iron core 7' is the space between the clamping body 1
It will be adjusted according to the amount of screwing of 2'.

Therefore, in this embodiment, the gap adjustment is performed using the tightening body 1.
There is also the possibility that the iron core 7' is provided integrally with the bottomed cylinder 8', with the load being placed on the bottomed cylinder 8'.

In this embodiment, the clamping body 12' is also used as an acoustic housing to simplify the structure, but it is also possible to use a clamping body that does not double as an acoustic housing.

4 and 5 show other embodiments of the buzzer according to the present invention.

The feature of these embodiments is that the stepped portion 8 into which the rubber magnet 7 is inserted
Rubber magnet 9 is shaped deeply into 'b' and surrounds iron core 7'.
′ was placed.

The functions and effects of these embodiments are almost the same as those shown in FIG. 3, but since the length of the rubber magnet 7' in the axial direction is increased, there is an advantage that the performance can be improved.

As explained in detail above, the buzzer according to the present invention is a buzzer in which a magnetic metal diaphragm is vibrated by the interaction between an alternating current magnetic field and a direct current magnetic field to generate a vibration sound, in which an iron core with a coil that generates the alternating magnetic field is provided. A ring-shaped rubber magnet that generates the DC magnetic field is disposed on the rotating blade, and the metal diaphragm is supported via the rubber magnet, so that only a small current is passed through the coil. It reduces the weight as much as possible without losing the advantage of generating distortion-free vibration sound, and at the same time makes manufacturing easier. Moreover, it protects the metal diaphragm from external shocks and reduces its sound pressure level. It is possible to provide an inexpensive and highly reliable buzzer that stabilizes the frequency, absorbs high-frequency distortion, etc., and emits high-quality vibration sound.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional buzzer, FIG. 2 is a sectional view of a buzzer according to the present invention, and FIGS. 3, 4, and 5 are sectional views of other embodiments of the buzzer according to the present invention, respectively. are shown respectively. 7... Iron core, 9,9'... Rubber magnet,
7a...5 Coil, 10...Vibration plate.

Claims (8)

[Scope of utility model registration request] (1) In a buzzer that generates vibration sound by vibrating a magnetic metal diaphragm through interaction between an alternating current magnetic field and a direct current magnetic field, the direct current magnetic field is generated around an iron core with a coil that generates the alternating current magnetic field. A buzzer characterized in that a rubber magnet is coaxially arranged to support the magnetic metal diaphragm via the rubber magnet. (2) The buzzer according to claim 1 of the utility model registration claim, characterized in that the rubber magnet is fitted inside a bottomed cylindrical body having the iron core erected at the bottom. . (3) The buzzer according to claim 2, wherein the rubber magnet is disposed around the tip of the iron core. (4) The buzzer according to claim 2, wherein the rubber magnet is provided so as to surround the iron core. (5) The magnetic metal diaphragm is placed on the rubber magnet, and the outer peripheral edges of the magnetic metal diaphragm and the rubber magnet are fastened between a clamping body and the bottomed cylinder. A buzzer according to claim 2, 3, or 4 of the utility model registration claim characterized by: (6) The buzzer according to claim 5, wherein the tightening body is an acoustic housing. (7) Utility model registration claims 2, 3 and 4, characterized in that the bottomed cylinder is made of a non-magnetic material.
The buzzer according to paragraph 5 or paragraph 6. (8) The buzzer according to claim 1, wherein the rubber magnet is provided on a flat plate to which the iron core is attached.