JPS612499A - Manufacture of platy diaphragm - Google Patents

Abstract

PURPOSE:To improve the reliability of the adhesive force between a skin material and adhesive film and to perform the bonding at ordinary temperature, by bonding the hot fusing type adhesive film to one surface of the skin material by using a solution type bonding agent of reaction-sensitive moisture setting urethane or epoxy adhesive which can bond at ordinary temperature. CONSTITUTION:A skin material 21 fed in the form of a rolled material is coated with a moisture setting polyurethane solution 41 at one surface while the skin material 21 is passed through the contacting section of a bottom roll 43 which is coated with the solution over the entire peripheral surface of the roll and a clean top roll 44 by means of an applying roll 42, whose lower half section is dipped in the bath of the moisture settng pooyurethane solution 41. A nylon-made adhesive film 22 also fed in the form of a rolled material and the skin material 21 coated with solution 41 at one surface are put together by means of rotating rolls 45, and then bonded to each other when passing through a humidifying device 46. The skin material 21 and adhesive film 22 bonded to each other are wound around a roll as a skin material with adhesive film 24.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a flat diaphragm for speakers used in various electroacoustic devices.

(Structure of conventional example and its problems) First, the structure of a flat speaker using a flat diaphragm will be explained with reference to FIG. The flat speaker has a center pole 1, and a tom plate 2 has a ring-shaped magnet 3 and a circular top plate 4 stacked and fixed thereon, and a magnetic gap 5 is formed in the upper part of the field part.
The voice coil 6 inserted into the drive cone 7 fixes the flat plate-like diaphragm 8 connected to the center with the gasket 10 via an edge 9 such as a free edge.
7 Seam 11-e! It has a structure in which the disc coil 6 is held correctly at the center of the magnetic gap 5 by a damper 12 fixed to the Z frame 11.

A method of manufacturing a flat diaphragm used in such a flat speaker will be explained with reference to FIGS. 2 and 3.

Fig. 2 shows the manufacturing process of the skin material with adhesive film, in which the skin material 21 and the adhesive film 22 supplied in roll form are stacked on top of each other, and two pieces are kept at a temperature higher than the melting point of the adhesive film 22. The adhesive film-attached skin material 24 having the adhesive film 22 heat-sealed on one side is wound up into a roll through the rotating rolls 23, thereby obtaining the adhesive film-attached skin material 24.

Figure 3 shows the above-mentioned cut skin material 32 with adhesive film.
and 34 to both sides of a core material 33 to form a flat diaphragm.The adhesive film surface is placed on the lower mold 31 of a press mold held at a temperature higher than the melting point of the adhesive film. The skin material 32 with adhesive film is placed on top, the core material 33 is placed on top of it, and the skin material 34 with adhesive film is placed on top of the core material 33 with the adhesive film side facing down, and then the adhesive film is melted. When pressed with the upper mold 35 of a press mold held at a temperature above 100 yen, the adhesive film melts and a flat diaphragm in which the skin materials 32 and 34 are adhered to both surfaces of the core material 33 is obtained.

In the manufacturing process as described above, in the rolling process shown in Figure 2, tensile stress is generated in the skin material during cooling due to the difference in thermal expansion coefficient between the skin material and the film because the adhesive film is melted at high temperature. Skin materials such as aluminum have the problem of wrinkles. In addition, when winding up the adhesive film-attached skin material 24 to which the adhesive film 22 is heat-sealed, the adhesive film-attached skin material 24
If cooling is insufficient, there is also a problem that the surface of the skin material 24 with adhesive film and the surface of the adhesive film 22 of the skin material 24 with adhesive film that is wound overlappingly will cause adhesion. Furthermore, when storing the skin material 24 with the adhesive film that has been wound up, there is a problem in that when the outside temperature rises in summer, the skin materials with the adhesive film tend to adhere to each other.

(Objective of the Invention) The present invention solves the above-mentioned drawbacks, and improves the reliability of the adhesive force between the skin material and the adhesive film. The purpose is to provide a method for manufacturing plates.

(Structure of the Invention) In the present invention, the rolling process of heat-sealing the skin material and the adhesive film is carried out on one side of the skin material using a reactive moisture-curing urethane or epoxy solution adhesive that can be bonded at room temperature. This method replaces the roll process in which high-temperature melting adhesive films are bonded together.

(Description of Examples) A method of manufacturing a flat diaphragm according to the present invention will be explained with reference to FIGS. 3 and 4. FIG. 3 is a diagram used to explain the conventional manufacturing method, but is used because there is no change in this process.

FIG. 4 shows the manufacturing process of the skin material with adhesive film according to the present invention, in which the skin material 21 is supplied in a roll material.
Using the coating roll 42 whose lower half is immersed in the path of the moisture-curing polyurethane solution 41, the coating is carried out between the lower roll 43, which has been coated with the moisture-curable polyurethane solution on the entire circumferential surface of the roll, and the clean upper roll 440. During the pass, one side is coated with the moisture-curing polyurethane solution described above. A nylon adhesive film 22 supplied as a roll material and a skin material 2 coated on one side with the above-mentioned moisture-curing polyurethane solution.
1 are superimposed on each other by a rotating roll 45, and then transferred to the humidifying device 4.
6, the adhesion is completed and the skin material 24 with adhesive film is wound up into a roll.

As mentioned above, FIG. 3 shows the process of manufacturing a flat diaphragm by bonding the cut pieces of the skin material 24 with the adhesive film on both sides of the core material, but since the process is subject to change, it will not be described here. Omitted.

Through the above steps, a flat imaging plate according to the present invention is obtained.

(Effects of the Invention) According to the present invention, the reliability of the adhesive force between the skin material and the adhesive film can be greatly improved, and accidents that occur when winding into a roll or when storing the roll can be completely eliminated.

Furthermore, the roll process for producing the skin material with adhesive film can be performed using simple equipment that can be processed at room temperature.

As a result of the above effects, the manufacturing cost of flat diaphragms can be significantly reduced, making it possible to supply inexpensive speakers.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a flat speaker, Fig. 2 is a conventional roll manufacturing process diagram of a skin material with an adhesive film, Fig. 3 is a hot pressing process diagram of a flat diaphragm, and Fig. 4 is an adhesive film according to the present invention. FIG. 3 is a process diagram of a method for manufacturing rolls of skin material. 1...Center bolt, 2...Bottom plate, 3
... Ring magnet, 4 ... Top plate, 5 Magnetic gap, 6 ... Voice coil, 7 ... Drive cone, 8 ... Flat diaphragm, 9 ... Edge, 10 ... Gasket, 11...Frame, 12...Danno 1°-
121...Skin material, 22...Adhesive film, 23
．． 45...Rotating roll, 24.32.34...Kisskin material with adhesive film, 31...Press mold lower mold, 3
5... Press mold upper mold, 41... Moisture-curing urethane solution, 42... Coating roll, 43... Lower roll, 4
4. Upper roll, 46. Humidifier. Figure 1 Figure 2

Claims (1)

[Claims] In the manufacturing method of a flat diaphragm having a three-layer structure in which skin materials are bonded to both sides of a core material, a high-temperature melting adhesive film is attached to one side of the skin material using a moisture-curing urethane or epoxy adhesive. A method for manufacturing a flat diaphragm, which is characterized by pasting together and bonding this to a core material by heat pressure welding.