JPH0263034B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a seat body and a seat body that are fused by ultrasonic welding.

First, a conventional example will be explained with reference to FIGS. 1 to 4.

FIG. 1 shows a cross section of the seat body, showing a skin 1, a urethane foam mold 2 constituting the cushion material, and a fused portion 2a between them (in the figure, an example of 5
).

As shown in FIG. 2, in order to fuse the skin 1 to the urethane foam mold 2 using high-frequency current, a high-frequency welding lower mold (width t) 13 and a high-frequency welding upper mold 14 (upside down during implementation) are used. )
During this process, the skin and urethane foam mold (hereinafter simply referred to as mold) 2 are placed one on top of the other, compressed to a certain extent, and a high frequency current is applied to perform heat-generating fusion. The portion 2a of the width t partially softens due to heat generation, and when the pressure of the lower mold 13 is released, the elasticity of the urethane in the portion of the mold 2 other than the width t restores the original shape shown in FIG. When restoring, both sides of the width t are often cut at the cut surface 2b. In such a state, the skin 1 is not sufficiently fused to the mold 2 at the fused portion 2a, resulting in a defective product. Although not shown, if the width t is narrow, the width t
The cut surfaces 2b on both sides of the cut surface 2b may be substantially one cut surface. In any case, it is extremely undesirable for the cushion body, which is the main functional part of the seat body, to be separated in this way.

Fig. 3 shows that in order to avoid the above-mentioned phenomenon of cutting, the inside of the mold 2 is impregnated with a welding material to a width t in the welding part 20, and then heated to a temperature lower than the softening temperature of the mold 2 by high frequency or the like. A conventional example is shown in which only the adhesive material is melted by heating to fuse the outer skin 1, mold 2, and back base fabric 3. If this is done, the cutting phenomenon will not occur, but the mold 2 will be compressed and thinned at the fused portion 2a and fused, so the entire mold 2 will become hard, and the height H shown in FIG. Third
In the figure, the height is as low as h, which has the drawbacks of poor appearance and volume, and high cost.

FIG. 4 shows a case where the back base fabric 3 of FIG. 3 is not present, and the mold 2 is fused to the outer skin 1 at the fused portion 2a. However, since there is no backing fabric 3, no unevenness is formed on the upper surface of the outer skin 1, and the appearance of unevenness when viewed from both sides of the outer skin 1 is either absent or minimal, which is unfavorable in terms of design.

The present invention eliminates the drawbacks of the conventional examples described above, and uses a new manufacturing method in which even the wading is fused in one step, and aims to provide a seat body that is low in cost and excellent in function and appearance. This is the purpose.

The present invention will now be described in detail with reference to FIGS. 5 to 11 showing preferred embodiments of the present invention.

The seat body shown in FIG. 5 is a seat body formed according to the present invention, and this figure corresponds to the conventional example shown in FIG. In this embodiment of the present invention, on the hard-mesh urethane foam mold 2, which is the main functional part of the seat cushion body, a soft-mesh urethane foam of relatively thin thickness is used to provide a soft tactile sensation to the seated person. Wading 4, which is the body, is overlapped, and the epidermis 1 is placed on top of this. An ultrasonic tool horn (not shown) having a shape corresponding to the width t of the high-frequency welding lower mold 13 shown in FIG. 2 is pressed against the stacked body from above the skin 1. This ultrasonic tool horn applies ultrasonic vibrations to the skin 1 and the wading 4.
This causes exothermic welding near the interface between the wading 4 and the mold 2, and near the interface between the wading 4 and the mold 2. The heat-generating welds are the welds 4a and 4b, and these are limited to the area pressed by the tool horn. In this configuration, in the case of fusion bonding, no cut surface 2b is generated in the mold 2 (cushion body) compared to that in FIG. This is a big advantage. Also, the fused part 4a
Since the can be deeply recessed and fused, the upper layer of the wading 4 and the mold 2 can be strongly compressed by the skin 1, so that the wading 4 and the mold 2 can be made moderately hard in parts. Therefore, the feeling when sitting can be changed.

Wading 4 is used in conventional machine-sewn seat covers, but according to the present invention, the cost is lower (less man-hours are required) compared to a seat body in which the mold is covered with a conventional machine-sewn seat cover. , a seat body with an excellent shape can be provided.

Since the surface of the mold 2 is covered with the wadding 4, it does not need to be as smooth as the surface of a conventional mold.

Further, the back base fabric 3 may be adhered to the mold 2 in advance, or may be integrated when the mold 2 is integrally foamed.

Fig. 6 shows an example in which the skin 1 is fused by ultrasonic waves to a stacked body of the mold 2 and the wading 4 without the backing fabric 3, and the cross section below the line A-A in Fig. 3 is removed. It is.

Comparing FIG. 4 with FIG. 6, the embodiment of the present invention shown in FIG. 6 has an uneven shape on the skin 1 side, which is superior in terms of design, and the presence of wading 4 also improves functionality. Are better.

The embodiment shown in FIG. 7 is an embodiment in which the fused portion 4a between the skin 1 and the thinly sliced wadding 4 of urethane shown in FIG. 5 is relatively thin, and the surface of the mold 2 is rather flat. .

Conventional seat covers have a draw cloth attached to them for fixing to the mold 2 or the frame of the seat body, but this is not necessary in FIG. 7. Furthermore, sliced urethane may be further interposed between the skin 1 and the wadding 4.

FIG. 8 shows that when a deep concave mold groove 2d is formed in the mold 2 for reasons such as design, the depth of the groove is formed by generating vibration heat using ultrasonic waves instead of pre-molding. Give an example. In this case, the ultrasonic machining conditions should be selected to create a deep groove 2.
d is melted to fuse the epidermis 1. The shape of the groove 2d in this case depends on the shape of the ultrasonic welding tool horn.

The embodiment shown in FIG.
In this seat body, a circular plate 5 serving as a base material for forming a button-shaped part is placed between them, covered with a skin 1, and ultrasonically fused at a welding part 4a to form a button-shaped part on the skin 1. In this case, the fusion mold has a ring-shaped mold that serves as a guide for forming the button-shaped part, and the fusion part 4a is pressed along the circular end of the circular plate 5 and fused to the wading 4 and the mold 2. Ru. The part of the epidermis 1 indicated by the dotted line is shown in FIG.
A case is shown in which the mold 2 does not have a conical hole and the upper surface of the mold 2 has a flat shape.

FIG. 10 shows an example in which a draw cloth 6 necessary for attaching a seat body to a frame or a spring body is attached to the lower surface of the mold 2. The draw cloth 6 is fused by ultrasonic waves.

Figure 11 shows the epidermis 1a and epidermis 1b of the mid-crop area.
Layer them together and place them on the mold 2 and wading 4, and use ultrasonic waves to seal the fused part 4a to the midsection epidermis 1.
a. A seat body in which the calyx skin 1b and the calyx skin 1b are simultaneously fused to each other at the overlapping parts and the bead 7 on the top surface is molded together, and the color, pattern, and material of the calyx skin 1a and the calyx skin 1b are If the selection is made taking these factors into consideration, the design will be excellent. Incidentally, the center part of the seat surface on the right side in FIG. 11 is usually called the bending part.

If the bank part 2c of the mold 2 is high, the calyx skin 1b is cut separately to fit the shape of the bank part 2c, but if the bank part 2c is low, the calyx skin 1a and the calyx skin 1b are cut separately. What is the epidermis 1b?1
A piece of epidermis may also be used.

In all of FIGS. 5 to 11, the cushion body is described as a urethane foam mold 2, but this may be a flat slab made by slicing urethane foam, a lamination of these, or a curved surface formed by cutting and molding.
It may be formed into various shapes such as grooves.

Furthermore, the material is not limited to urethane.
If it is fused by ultrasonic fusion method,
Other foam cushioning materials may also be used.

In the ultrasonic welding according to the present invention, the depth of the welded portion of the skin 1 can be changed in whole or in part by appropriately changing the welding conditions such as pressure and time.

According to the present invention, skin materials and shapes that are difficult to fuse by conventional high-frequency processing, or skin materials that suffer from loss of sparks generated by high-frequency current, can be used without problems.

Moreover, when using ultrasonic waves, it is possible to obtain a seat body that is lower in cost, has more stable quality, and has a better design form than seat bodies manufactured by other fusion bonding methods.

[Brief explanation of the drawing]

Figures 1 to 4 show conventional examples, Figure 1 is a sectional view of the seat body, Figure 2 is a sectional view explaining the high frequency fusion method, and Figures 3 and 4 are both conventional examples of the seat body. FIGS. 5 to 11 are sectional views showing examples of the present invention, FIGS. 5, 6, and 7 are sectional views showing embodiments of the present invention, and FIG. 8 is a partial sectional view showing grooves. Figure 9 is a partial sectional view of the button-shaped part, Figure 10 is a partial sectional view of an example in which the draw cloth is fused, and Figure 1
Figure 1 is a cross-sectional view of an example in which the overlapping skins and beads are fused together. 1... Epidermis, 1a... Midori part epidermis, 1b...
Sepal skin, 2... Urethane mold, 3... Back base fabric, 4... Wading, 4a... Fusion part, 2c
... Bank part, 2d ... Groove part, 5 ... Circular plate, 6 ... Drawn cloth, 7 ... Beaded part.

Claims (1)

[Scope of Claims] 1 Layer the foam wading and skin on the foam seat cushion body, apply an ultrasonic tool horn from above to apply ultrasonic vibration, and create a gap between the cushion body and the wading body. and a method for manufacturing a seat body by ultrasonic fusion, characterized in that the wading and the skin are partially melted and fused using ultrasonic waves. 2. A seat body formed by ultrasonic welding, characterized in that the foam seat cushion body, the foam wadding, and the skin are partially fused by ultrasonic waves at the required welding portions between them.