JPS63153998A - Speaker - Google Patents

Abstract

PURPOSE:To improve frequency characteristics and transient characteristics by closing the through hole of a holder which is connected to a diaphragm by a soft porous body with a 2nd soft porous body with low density. CONSTITUTION:The through hole of the holder 13 of an acoustic resistor 12 connected to the diaphragm 6 by a 1st soft porous body 14 is closed with a 2nd low-density soft porous body 15. A damping force is generated by the vibration of the diaphragm 6 with any distortion because of the porous body 15 which is not deformed and constant in resistance value even when the vibration amplitude of the diaphragm 6 is large to obtain a speaker whose frequency characteristics and transient characteristics 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 a cone speaker or a dome speaker, damping 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. 150121/1983 discloses a technique for attaching a mechanical element to a diaphragm via a viscoelastic body, thereby preventing 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. Technology that inserts a larger support member between the flat diaphragm and the frame and adheres both sides to prevent lateral vibration of the diaphragm and 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 reduce acoustic distortion especially when the vibration width of the vibrating body is large. It is an object of the present invention to provide a speaker equipped with an acoustic resistor on a diaphragm, which can further improve the acoustic efficiency of the speaker.

[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. A through hole is provided in the holder, and a first soft porous body is provided in an annular shape between the holder and the diaphragm so as to surround the through hole, and the through hole has a lower density than the first soft porous body. This is achieved by the above-mentioned speaker characterized in that it is closed with a second soft porous body.

[Effect]

By configuring the ridges, the second soft porous body with a low density provided in the through hole of the holder can especially vibrate through the first soft porous body provided between the diaphragm and the holder. Prevents acoustic distortion when the vibration width of the plate is large,
Frequency characteristics and transient characteristics can be significantly improved.

Therefore, when the diaphragm vibrates, the holder, diaphragm and first
, the volume of the space surrounded by the second soft porous body fluctuates periodically, and at this time, air flows in the soft porous body, resulting in a flow resistance force, which causes damage to the diaphragm. exerts braking force. The first soft porous body itself undergoes deformation such as compression when the diaphragm moves, and when the amplitude of the diaphragm is large, the flow resistance value in the first soft porous body changes. If a flow path is not provided for the air filling the body, the braking force generated will be excessive and cause distortion. However, in the present invention, a low-density second porous body is provided, and this resistance value is constant without being deformed by the vibration of the diaphragm. Appropriate braking force can be generated without distortion even when the amplitude of the diaphragm is large.

That is, the feature of the acoustic resistor according to the present invention is that the second soft porous body having a lower density than the first soft porous body is provided in the through hole of the holder to reduce the air flow generated by the vibration of the diaphragm. Most of the air flow in the second soft porous body,
This brakes the diaphragm, and the low-density second soft porous body does not undergo deformation such as compression even when the diaphragm moves, and even when the vibration amplitude of the diaphragm is large, the second soft porous body has a low density. It is designed to maintain a constant flow resistance value in the body and improve frequency characteristics.

〔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 sectional 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
4 is a ball piece, 4 is a yoke plate, and 5 is a yoke, and the cone speaker 1 includes a magnet 2, a pole 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, 8 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.

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

In FIG. 2, 6 is a diaphragm, 12 is an acoustic resistor, 13 is a holder, 14 is an annular first soft porous body, and 15 is a cylindrical second soft porous body.

This acoustic resistor 12 is provided with a holder 13 whose lower part is a flat plate approximately parallel to the diaphragm 6 , a through hole is provided in the center and a cylindrical portion protrudes from the holder 13 , and between the diaphragm 6 and the holder 13 . A first annular soft porous body 14 is provided, and a cylindrical second soft porous body 15 is inserted into the cylindrical portion of the holder 13.

For the first and second soft porous bodies 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.

Accordingly, in the present invention, the second soft porous body 15 has a lower density than the first soft porous body 14.

In the present invention, the hole diameter and protrusion height of the cylindrical portion of the holder 13 are determined to provide the best braking effect.

In the acoustic resistor 12, when the diaphragm 6 vibrates, most of the air due to the vibration is transferred to the second soft porous body 15.
The viscous resistance of the air is generated within the second soft porous body 15, and since the second soft porous body 15 is not affected by the vibration of the diaphragm 6, the viscous resistance value remains constant even when the amplitude is large. As a result, the vibration of the diaphragm 6 can be damped without producing acoustic distortion, and the frequency characteristics can be improved.

Note that the acoustic resistors 12 may be distributed on the surface of the diaphragm 6 symmetrically with respect to the central axis. In addition, in the case shown in FIG. 2, both the first and second soft porous bodies are annular bodies continuous along one contour of the diaphragm 6, and the radial cross section thereof is exactly as shown in FIG. It may be configured to be similar to.

[Effects of the Invention] Since the present invention is structured like a ridge, 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 embodiment on the ridge; 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, and the present invention It encompasses all of the above.

[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 body is provided between the holder and the diaphragm, a through hole is provided in the holder, A first soft porous body is provided in an annular shape between the holder and the diaphragm so as to surround the through hole, and the through hole is surrounded by a second soft porous body having a lower density than the first soft porous body. The above speaker is characterized by being occluded.