JPS6122396Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a flat diaphragm made by laminating skin materials on both sides of a core material so as to form a large number of small air chambers.

Such diaphragms have the advantage of being lightweight because they have a large number of small air chambers, but the skin material is generally made of thermoplastic resin such as vinyl chloride, so heat is not applied to the diaphragm. When the skin material is softened and the air in the small air chamber is thermally expanded, the air pressure in the small air chamber increases, and the force of this increased air pressure causes a problem in that convex portions are formed on the surface of the skin material. .

There were also other problems, such as the skin material bonded to the core material easily peeling off at the periphery, or the periphery of the diaphragm not having sufficient strength, resulting in abnormal resonance.

This invention was made in view of the above points,
The purpose is to provide a planar diaphragm that does not cause deformation of the skin material due to heating and has increased strength in the peripheral portion.

An embodiment of the present invention will be described below with reference to the drawings. 1 is a core material having a large number of honeycomb-shaped cells, and 2a and 2b are skins made of thermoplastic resin such as vinyl chloride bonded to both sides of the core material 1. The material 3 is an edge for supporting the peripheral portion of the flat diaphragm and incorporating it into the speaker. Above core material 1
The skin materials 2a and 2b form a large number of small air chambers 4 on the diaphragm, and the core material 1 is provided with ventilation holes 1a to communicate the small air chambers 4 with the outside air. Further, the skin materials 2a and 2b are bent toward each other around the core material 1. Both skin materials 2
A gap 2c is created between the bent portions 2a' and 2b' of a and 2b.

Note that this bending of the skin material
This is easily done by softening the peripheral parts of the skin materials 2a, 2b, and then the bent parts 2a', 2b', which are cooled, harden to increase the rigidity of the peripheral parts of the skin materials 2a, 2b, thereby increasing the rigidity of the peripheral parts of the diaphragm. This will increase the strength of the part.

In the example of FIG. 3, only one skin material 2a, especially the side where the edge 3 is attached, is removed from the other skin material 2b.
In this case, there is also a gap 2c between the core material 1 and the other skin material 2b so that ventilation through the ventilation holes 1a provided in the core material 1 is not obstructed.
is formed.

As described above, in the present invention, the core material is provided with ventilation holes, and at least one of the skin materials is bent at the periphery of the core material to the extent that the ventilation through the ventilation holes is not inhibited. Even if the air inside the small air chamber is thermally expanded by heat, the air inside the small air chamber escapes to the outside air through the ventilation hole and does not increase the pressure inside the small air chamber, which causes the skin material to break down, which was previously caused by the increase in air pressure. In addition to eliminating the occurrence of deformation, the bent portions of the skin material around the core material increase the strength of the skin material and, by extension, the surrounding area of the diaphragm, and also have excellent practical effects such as preventing peeling of the skin material. It is something that plays.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a sectional view of the first embodiment, FIG. 2 is a partially cutaway perspective view of FIG. 1, and FIG. 3 is a second embodiment. It is a sectional view showing an example. 1...Core material, 1a...Vent hole, 2a, 2b...
...skin material, 2a', 2b'...bent portion, 4...small air chamber.

Claims (1)

[Scope of utility model registration request] In a flat diaphragm made by laminating skin materials on both sides of a core material to form a large number of small air chambers,
Ventilation holes for communicating the small air chambers with the outside air are provided in the core material, and at least one of the skin materials is placed around the outer periphery of the core material to the extent that ventilation with the outside air through the ventilation holes is not inhibited. A flat diaphragm characterized by being bent towards.