JPS63153999A - Speaker - Google Patents

Abstract

PURPOSE:To improve frequency characteristics and transient characteristics by forming vent holes in the holder of an acoustic resistor. CONSTITUTION:The plural holes 13a are formed in the holder 3 of the acoustic resistor 12 which contacts a diaphragm 6 and a soft porous body 14, and vibrations of the diaphragm is damped excellently by the viscous resistance of air passing through the gap in the porous body 14 without any acoustic distortion. Consequently, the frequency characteristics and transient characteristics of the speaker are improved greatly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a speaker in which an acoustic resistor is provided on a diaphragm.

[Conventional technology]

Conventionally, in cone speakers or dome speakers, braking is performed mainly by electromagnetic force generated in the voice coil in order to improve the frequency characteristics and transient characteristics of the speaker.

In the case of braking using the electromagnetic force of a coil, if it is connected to an amplifier through a network or attenuator, the braking force decreases in a certain frequency range, resulting in insufficient braking and deterioration of transient characteristics.

As a method of damping the high-frequency division vibration of the hard dome and the piston vibration that occurs when the diaphragm moves in unison, foam rubber, etc. may be pasted on the back side of the diaphragm, or soft sound-absorbing material may be placed in the space behind the diaphragm as a diaphragm. It is known that the material is placed in contact with the material to act as a braking resistance, but it is not very effective in improving frequency characteristics and transient characteristics.

Further, Japanese Patent Application Laid-Open No. 54-150121 discloses a technique in which a mechanical element is attached to a diaphragm to prevent split resonance of the diaphragm.

Furthermore, Japanese Utility Model Application Publication No. 56-6192 discloses an elastic material having air permeability and sound absorption properties, which has a disk shape with a central hole, the inner circumference of which is fixed to the outer circumference of the diaphragm, and the outer circumference of which is fixed to the frame. A speaker is shown characterized in that it includes a material.

In addition, Japanese Utility Model Application Publication No. 54-181924 discloses that a flat speaker is made of a sound-absorbing elastic material and is formed into a flat annular shape, the outer diameter is smaller than the outer diameter of the flat diaphragm, and the inner diameter is the outer diameter of the voice coil. A larger support member is inserted between the flat diaphragm and the frame, and both sides are glued together to prevent lateral vibration of the diaphragm and to absorb standing waves between the frame and the diaphragm. It is shown.

However, none of these types of ideas makes the acoustic resistance to the diaphragm suitable, and since the equivalent mass of the diaphragm is increased, the high frequency characteristics and transient characteristics of the speaker deteriorate, resulting in acoustic distortion. There was a problem in that it caused

[Problem that the invention seeks to solve]

The present invention was made from the viewpoint of ridges, and the purpose of the present invention is to significantly improve frequency characteristics and transient characteristics, and to prevent acoustic distortion in high frequency ranges. An object of the present invention is to provide a speaker in which a diaphragm is equipped with an acoustic resistor that can further improve acoustic efficiency.

[Means for solving problems]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a speaker equipped with an acoustic resistor in which a holder is fixedly provided substantially parallel to a diaphragm, and a soft porous body is provided between the holder and the diaphragm. This is achieved by the above speaker characterized in that the holder is provided with a plurality of ventilation holes.

[Effect]

By configuring it like a ridge, acoustic distortion is prevented by the plurality of ventilation holes in the holder via the soft porous body provided between the diaphragm and the holder, and the frequency characteristics and transient characteristics are significantly improved. be able to.

The characteristics of the acoustic resistor are that a soft porous body is provided between a fixed holder and the diaphragm to form the acoustic resistor, and the displacement of the diaphragm is controlled by the air flow in the soft porous body. By providing multiple ventilation holes in the holder, the length of the air flow path in the soft porous material is shortened, and by using a large amount of soft porous material, the acoustic resistance in the soft porous material can be reduced to create acoustic distortion. It is designed to be large within an allowable range that can prevent this, so that braking force can be obtained effectively and frequency characteristics are improved.

〔Example〕

Hereinafter, the details of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of a speaker according to the present invention, and FIG. 2 is an enlarged perspective view showing details of an acoustic resistor thereof.

First, FIG. 1 will be explained.

In Figure 1, 1 is a cone speaker, 2 is a magnet, and 3
is a pole piece, 4 is a yoke plate, and 5 is a cork, and the cone speaker 1 includes a magnet 2, a ball piece 3, a yoke plate 4, and a yoke 5 to form a magnetic circuit.

6 is a diaphragm, 7 is an edge that supports the outer periphery of the diaphragm 6, B is a damper that supports the center of the diaphragm 6, 9 is a voice coil attached to the lower part of the diaphragm 6, and 10
1 is a center cap, 11 is a frame, and 12 is an acoustic resistor attached to the rear surface of the diaphragm 6.

The acoustic resistor 12 is arranged so as to be in contact with the diaphragm 6, and is fixed by a mounting device using the frame of the speaker body or the like.

Incidentally, the acoustic resistor may be annular and continuous along one equiline of the diaphragm 6.

Next, the acoustic resistor 12 used in the speaker according to the present invention will be explained in detail.

In Figure 2, 12 is an acoustic resistor, 13 is a holder, 13a
, 13a are a plurality of holes provided in the holder 13, 1
4 is a soft porous body.

This acoustic resistor 12 includes a plate-shaped holder 13 having a plurality of holes provided substantially parallel to a diaphragm 6, and a soft porous body 14 provided between the diaphragm 6 and the holder 13.

As the soft porous body 14, a sponge such as a soft polyurethane having continuous cells, a fibrous material such as felt or glass wool, or other sound absorbing material is used.

In the present invention, the position, number, and diameter of the plurality of holes 13a of the holder 13 are determined so as to provide the best braking effect.

When the diaphragm 6 vibrates, the volume of the space inside the soft porous body 14 changes due to repeated deformation of contraction and restoration of the soft porous body 14, and as a result, the air in the space changes direction and flows. Braking is achieved by the viscous resistance caused by the flow of air.

On the other hand, since the holder 13 is fixed to the frame 11 via a bracket, it does not vibrate at all, and only the portion of the soft porous body 14 near the diaphragm 6 vibrates, and as a result, the volume of the space inside the soft porous body 14 is reduced. The air in the space flows and repeatedly flows out and inflow from the plurality of holes 13a, 13a of the holder 13 and the side surfaces around the soft porous body 14. The viscous resistance of the air generated when the air passes through the gaps in the soft porous body 14 damps the vibration of the diaphragm 6, thereby preventing acoustic distortion.

In this way, when trying to obtain damping force for a speaker using an acoustic resistor, when sound waves pass through the space of a soft porous body,
If the dimensions of the soft porous material are equal to or larger than the wavelength λ of the sound wave, distortion will occur, so there is a limit to the amount of soft porous material that can be used. The soft porous body 14 having the above-mentioned shape and the holder 13 having a plurality of holes are used to increase the total amount of the damping force and the braking force.

[Effects of the Invention] Since the present invention is configured as described above, when the present invention is applied, it is possible to effectively damp the vibrating part of the speaker and the divided vibration of the diaphragm, and the frequency characteristics and transient characteristics are improved. It can provide speakers.

Note that the configuration of the present invention is not limited to the above embodiments (for example, the shapes of the soft porous body and the holder can be freely changed within the scope of the purpose of the present invention; It encompasses all of these.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a speaker according to the present invention, and FIG. 2 is an enlarged perspective view showing details of an acoustic resistor thereof.

Claims (1)

[Claims] 1) In a speaker equipped with an acoustic resistor in which a holder is fixedly provided substantially parallel to the diaphragm and a soft porous material is provided between the holder and the diaphragm, the holder is provided with a plurality of ventilation holes. The above-mentioned speaker is characterized by being provided with: