JPS6159600B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speaker diaphragm in which a surface material is bonded to the surface of a honeycomb-shaped core material, and provides a manufacturing method that can uniformly and firmly bond the honeycomb-shaped core material and the surface material. It is.

First, a conventional method of manufacturing this type of speaker diaphragm will be described.

FIG. 1 shows an unexpanded block 1 of honeycomb-like material. As shown in FIG. 2, this unstretched block 1 is made by laminating a large number of foils 2 such as aluminum foils, and bonding the necessary parts between adjacent foils 2 with an adhesive 3. FIG. 3 shows an unexpanded block 4 for one diaphragm, which is obtained by cutting the unexpanded block 1 shown in FIG. 1 as shown by broken lines.
One end a of the unexpanded block 4 for one diaphragm
Rotate and expand in a fan shape so that the side is the center.
FIGS. 4 and 5 show states in the middle of rotational expansion in directions b and b', respectively. By rotating and expanding further from the state shown in FIG. 5 and bonding both side surfaces 5 and 5', a flat circular core material 6 in which a large number of hexagonal cells are lined up is produced. As shown in FIG. 6, circular surface materials 7 and 7' made of foil such as aluminum foil are brought into contact with the surface of the core material 6 manufactured in this manner, thereby completing a speaker diaphragm. FIG. 7 is a partially cutaway top view of the surface material 7 of the completed speaker diaphragm.

In the above conventional row, the core material 6 has a surface material 7,
7', apply adhesive to the surface of the core material 6 with a brush or the like, and after drying this adhesive, place the surface materials 7, 7' on the surface of the core material 6, and then apply the adhesive to the surface of the core material 6. , 7' from the outside to melt the adhesive applied to the core material 6.
and the surface materials 7, 7'.

However, when applying the adhesive to the core material 6 using a brush or the like, there are disadvantages in that the adhesive is not applied uniformly, resulting in variations in the amount of adhesive applied and variations in adhesive strength.

Conventionally, an adhesive sheet is interposed between the core material 6 and the surface materials 7, 7', and the adhesive sheets are melted by heating and pressure.
A method of gluing 7' has been considered, but in such a method, the adhesive strength between the core material 6 and the surface materials 7, 7' is weak, and the surface materials 7, 7' separate from the core material 6. There were flaws.

The present invention eliminates the above-mentioned conventional drawbacks, and one embodiment of the present invention will be described below.

As shown in FIG. 8, the core material 6 is passed between rotating rollers 8 and 8' whose outer peripheral surfaces are coated with adhesive, and the adhesive is applied to the surface of the core material 6. This adhesive is a thermosetting polyamide adhesive, and is applied from the surface of the core material 6 to the inside of the core. The core material 6 coated with adhesive in this way is attached to the belt 9,
The core material 6 is sandwiched between the core materials 9' and transferred, but during this transfer, hot air is blown onto the core material 6 from a hot air blower 10.
By blowing this hot air, the solvent in the adhesive evaporates. In this way, the adhesive is applied to both sides of the core material 6.

On the other hand, the surface materials 11, 11' are coated with adhesive (thermosetting polyamide adhesive) on one side in advance.
and as shown in FIG. 9, on the jig 12,
The surface material 11', the core material 6, and the surface material 11 are placed and pressed from the top surface of the surface material 11 with a heated jig 13, and the adhesive and core material 6 applied to the surface materials 11, 11' are removed. After melting the adhesive applied to
Cool and harden these adhesives to form surface material 1.
1, 11' and the core material 6 are bonded together.

FIG. 10 is an enlarged view of the main parts of a speaker diaphragm manufactured by the manufacturing method of the present invention, and shows that the adhesive 14 has been applied to the inside of the upper and lower edges of the foil 6' constituting the core material 6. At the same time, an adhesive 15 is also applied to the surface material 11', and these adhesives 14 and 15 connect the core material 6 and the surface materials 11 and 11'.
is bonded, so the adhesive strength is strong and the surface material 1
1 and 11' will not peel off from the core material 6. FIG. 11 shows the relationship between adhesive and peel strength in the method of manufacturing a speaker diaphragm of this example. The horizontal axis represents the amount of thermosetting polyamide adhesive applied to the core material. , the vertical axis indicates peel strength.

As shown in curve A in Figure 11, the maximum peel strength when the thermosetting polyamide adhesive is applied only to the surface material is when 40 g/cm ² is applied, and the peel strength at this time is It is 280/cm. On the other hand, when 14 g/cm of thermosetting polyamide adhesive is applied to the core material, the peel strength becomes 1.2 Kg/cm, more than four times as strong. In addition, when the adhesive is made of thermoplastic polyamide, the peel strength is as shown in curve B.
The peel strength is considerably weaker than when a thermosetting polyamide adhesive is used.

As described above, by applying the thermosetting polyamide adhesive to both the surface materials 11, 11' and the core material 6 of the core material, the core material is 6 and surface material 11,1
1', and can also be bonded more firmly than other adhesives.

Further, in the present invention, the core material 6 is rotated by rotating rollers 8, 8'.
Since the adhesive is applied to the core material 6 by passing the adhesive between the core materials 6 and 6, there is an advantage that the adhesive can be applied uniformly to the core material 6. Furthermore, according to the present invention, since the adhesive is applied to the core material 6 by the rotating rollers 8, 8', the application speed is increased and the diaphragm can be manufactured in a short time.

The present invention has the above configuration, and according to the present invention, the following effects can be obtained.

(1) The surface material can be bonded to the core material more strongly than when adhesive is simply applied to the surface of the surface material, and it is also stronger than when adhesives other than thermosetting polyamide adhesives are used. , can be strongly bonded.

(2) Adhesive can be applied uniformly to the core material, and there is no variation in peel strength.

(3) Manufacturing time is shortened.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an unexpanded block made of honeycomb-like material, Fig. 2 is a partially enlarged top view of Fig. 1, Fig. 3 is a perspective view of an unexpanded block for one diaphragm, and Fig. 4 is a perspective view of an unexpanded block of honeycomb-like material.
Fig. 5 is a top view showing the state in which the unexpanded block is expanded, Fig. 6 is a side view showing the state in which the surface material is bonded to the core material, and Fig. 7 is a partially cutaway top view of the speaker diaphragm. 8 is a schematic diagram of one step in a method for manufacturing a speaker diaphragm according to an embodiment of the present invention, FIG. 9 is a side view of another step in the manufacturing method of the present invention, and FIG. FIG. 11, which is an enlarged perspective view of the main parts of the speaker diaphragm manufactured by the manufacturing method, is a characteristic diagram showing the relationship between peel strength and adhesive weight. 6... Core material, 8, 8'... Rotating roller, 9,
9'...Belt, 10...Hot air fan, 11,11'...
...Surface material, 12,13...Jig, 14,15...
glue.

Claims (1)

[Claims] 1. A core material made of expanded honeycomb-like material,
The thermosetting polyamide adhesive is applied to both sides of the core material by passing it between a pair of rotating rollers with a thermosetting polyamide adhesive adhered to the outer peripheral surface, and hot air is blown onto the core material. The solvent in the adhesive is evaporated, and a surface material coated with a thermosetting polyamide adhesive on one side is placed on the core material.
By pressing a heated jig against the surface material, the adhesive applied to both sides of the core material and the adhesive applied to one side of the surface material are melted, and then cooled to melt these adhesives. 1. A method of manufacturing a speaker diaphragm, which comprises curing an agent to bond the surface material and the core material.