JPS628639Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a flat speaker constructed by using a flat diaphragm and coupling the flat diaphragm and a voice coil with a coupling cone.

Generally, a flat speaker is constructed as shown in FIG.

That is, a ring-shaped magnet 4 and a ring-shaped upper plate 5 are assembled on a plate 3 having a center pole 2 with a through hole 1 in the center to form a magnetic circuit 6, and a frame 7 is attached to this magnetic circuit 6. The gasket 8 and the edge 10 attached to the peripheral edge of the flat diaphragm 9 are attached to the peripheral edge of the frame 7 by adhesive or the like, and the coupling cone 11 is connected to the lower surface of the flat diaphragm 9. The upper part of the voice coil 12 is connected to the center of the cone 11, and the middle part of the voice coil 12 is held by a damper 13, so that the lower part of the voice coil 12 is connected to the magnetic gap 14 of the magnetic circuit 6 without being eccentric. It is composed of inlays.

As an example of the flat diaphragm 9, one constructed by pasting surface materials on both sides of a honeycomb core is used, and the coupling cone 11 coupled to the lower surface of the flat diaphragm 9 is It is coupled to the nodal circle at the primary resonance frequency.

In such a flat plate speaker, as the outer diameter of the flat plate diaphragm 9 increases, the coupling cone 11 formed of aluminum or the like increases.
The outer diameter of the steel becomes larger and the thickness becomes thicker for strength reasons, but
When a large low-frequency input is applied, as shown in FIG. 2, stress is intensively applied to the part a of the coupling cone 11, causing the problem that it may break or break.

For this reason, in the past, the material thickness of the coupling cone 11 was made thick enough to withstand the above-mentioned stress as shown in FIG. This resulted in a large vibrating mass, resulting in poor efficiency.

The present invention eliminates the above-mentioned conventional drawbacks, and without increasing the mass of the coupling cone.
Moreover, the present invention aims to provide a flat speaker using a coupling cone that can sufficiently withstand the application of large low-frequency inputs.

That is, in the present invention, a coupling cone is constructed from a thin metal foil, and a lightweight reinforcing material made of reinforced aromatic polyamide fiber is bonded to the part of the coupling cone where stress is applied when a large low-frequency input is applied. The aim is to reduce the mass of the vibration system as a whole and obtain a highly efficient flat plate speaker.

Hereinafter, an embodiment of the flat plate speaker of the present invention will be described with reference to FIG.

Since the structure of the flat speaker is the same as that shown in FIG. 1, the coupling cone, which is a feature of the present invention, will be explained here.

As shown in FIG. 3, the coupling cone 11 of the present invention is molded from a light metal such as aluminum, has a horizontal portion 11a on the upper part that is connected to the lower surface of the flat diaphragm 9, and has a horizontal portion 11a that connects to the lower surface of the flat diaphragm 9. It has an inverted conical part 11b, and the inverted conical part 11b
Vertical section 11 that couples voice coil 12 to the lower end of
A reinforcing material 11d made of reinforcing aromatic polyamide fibers having an inverted conical shape is attached by adhesive or the like from the middle part to the lower end of the inner surface of the inverted conical part 11b. ing.

This reinforcing material 11d can be attached at the same time as the coupling cone 11 is formed. The reinforced aromatic polyamide fiber is used as the reinforcing material 11d because
This is due to the fact that it is a material with low density and high Young's modulus, hardly increases the mass of the vibration system, and is ideal for reinforcing areas where stress is concentrated.

As described above, the flat speaker of the present invention uses a coupling cone in which a reinforcing material mainly composed of reinforced aromatic polyamide fibers is coupled to the part where stress is concentrated when a large low-range input is applied. Even if the coupling cone is bent or damaged, it can be prevented from spreading, and the metal foil itself can withstand even if it is made thinner, making it possible to make the coupling cone smaller in mass. The effect is that highly efficient reproduction can be performed without increasing the vibrating mass of the speaker, which is of great practical value.

[Brief explanation of the drawing]

Figure 1 is a half-sectional view of a typical flat-plate speaker, Figure 2 is a half-sectional view of a coupling cone used in a conventional flat-plate speaker, and Figure 3 is an implementation of the coupling cone used in the flat-plate speaker of the present invention. FIG. 3 is a half-sectional view showing an example. 6... Magnetic circuit, 7... Frame, 9... Flat diaphragm, 10... Edge, 11... Coupling cone, 11a... Horizontal part, 11b... Inverted conical part, 11c... Vertical part, 11d...Reinforcement material, 12
...Voice coil, 13...Damper, 14...
Magnetic gap.

Claims (1)

[Scope of utility model registration request] The edge of a flat plate diaphragm is attached to the peripheral edge of the frame connected to the magnetic circuit, and reinforced aromatic polyamide fibers are attached to the lower surface of the flat plate diaphragm from the middle part near the connection part with the voice coil of the inverted conical part to the lower end part. A flat speaker comprising a coupling cone bonded to a reinforcing material made of material, and a voice coil fitted into the magnetic gap of the magnetic circuit coupled to the center of the coupling cone.