JP2003154535A - Method for manufacturing sheet pad for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a sheet pad for a vehicle capable of efficiently manufacturing the pad for the vehicle by one time molding operation. SOLUTION: The method for manufacturing the sheet pad for the vehicle comprises a step of supplying a stock 6 for molding a low-density foam onto the surface of a main bottom 4 at a high site side via a nozzle 7. The method further comprises the steps of supplying the stock 6 along the slope of the main bottom 4, and moistening the overall bottom 4 to expand the stock upward to increase the thickness from the bottom 4 to the low-density foam 6a. The method also comprises the steps of supplying the stock 9 for molding a high- density foam from a nozzle 8 to a liquid reservoir 5 after the foaming of the stock 6 is advanced to a certain degree, coating the upper mold 10 on a lower mold 1 to fix the molds. This stock 9 immediately starts foaming to the high- density foam 9a. The foam 9a is expanded from the reservoir 5 to the upper side of the foam 6a in a cavity 2. The foam 9a is brought into close contact with the foam 6a and integrated with the foam 6a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat pad manufacturing method, and in particular, an upper layer portion made of a low-density foam and a lower layer portion made of a high-density foam are integrally formed in the same mold. The present invention relates to a method for manufacturing a vehicle seat pad that is formed.

[0002]

2. Description of the Related Art A seat for a vehicle such as a passenger car is an upper layer portion having cushioning properties for providing a comfortable seating when an occupant is seated, and a lower portion of the upper layer portion, which is required for the seat. It is mainly composed of a lower layer side portion that bears structural strength and rigidity. A mounting member for mounting the seat on the vehicle body side is embedded in the lower seat portion so that a part of the mounting member protrudes from the back surface of the seat. The upper surface and side surfaces of the seat are covered with a cover material such as cloth or leather.

In conventional seats, the upper seat layer is made of flexible polyurethane foam and the lower seat layer is made of rigid hollow plastic, metal or high density foam. Japanese Patent Publication No. 8-509678 discloses that the seat lower layer portion is made of rigid polyurethane foam. In the same publication, a preformed lower layer portion is placed in a mold, a foaming stock solution for molding the upper layer portion is supplied into the mold, and foamed to form a low-density upper layer portion integrated with the lower layer portion. There is.

[0004]

When the lower layer portion is molded separately from the upper layer portion in this way, the molding step is required twice and two kinds of molds are required, which is troublesome and time-consuming. It was also expensive.

An object of the present invention is to provide a method for efficiently manufacturing a vehicle seat pad in which an upper layer portion made of a low density foam and a lower layer portion made of a high density foam are integrated. To do.

[0006]

SUMMARY OF THE INVENTION A method of manufacturing a vehicle seat pad according to the present invention uses a mold for a vehicle seat pad having an upper layer portion made of a low density foam and a lower layer portion made of a high density foam. In the method of manufacturing using, the mold comprises a cavity surrounded by a cavity bottom surface corresponding to the seat surface of the vehicle seat pad and a cavity side surface corresponding to the side surface of the vehicle seat pad. The one end side is provided with a liquid reservoir for accumulating the high-density foam stock solution, and the low-density foam stock solution is supplied to the bottom surface of the cavity other than the solution pool to foam the solution. And forming a high-density foam stock solution by supplying the high-density foam stock solution to the liquid storage section to form a foam, and forming a high-density foam from the liquid storage section to the upper side of the low-density foam. is there.

In such a method of the present invention, the low-density foaming raw material liquid is supplied to the surface of the bottom surface of the cavity other than the liquid reservoir (hereinafter, this surface may be referred to as the main bottom surface) to foam it. , The high-density foam stock solution supplied to the liquid reservoir is foamed, the high-density foam is foamed above the low-density foam previously foamed, and the low-density foam and the high-density foam are made into one gold. It is integrally molded in the mold. Therefore, the molding can be performed in a single molding step using one mold, and therefore the manufacturing efficiency of the vehicle seat pad is remarkably high.

In the present invention, it is preferable to incline the main bottom surface of the cavity and arrange the liquid reservoir on the higher side of the main bottom surface of the cavity. When the foaming undiluted solution for low-density foam is supplied to the inclined cavity main bottom surface, the undiluted solution spreads widely on the main bottom surface along the inclination, so that it becomes easy to wet the entire main bottom surface with the undiluted solution.

In the present invention, it is preferable that the main bottom surface and the liquid reservoir be partitioned by a ridge. The height of this ridge is 1 to 50 mm
A degree is preferable.

In the present invention, the main bottom surface may be provided with a convex portion extending in a direction intersecting with the inclination direction of the main bottom surface.

[0011]

DETAILED DESCRIPTION OF THE INVENTION Embodiments will be described below with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a method for manufacturing a vehicle seat pad according to an embodiment, and FIG. 2 is a cross-sectional view of the manufactured vehicle seat pad.

A metal mold for molding a vehicle seat pad comprises a lower mold (lower mold) 1 and an upper mold (upper mold) 10. The bottom surface of the cavity facing the cavity 2 of the lower mold 1 is divided into a main bottom surface 4 and a liquid reservoir 5 by a ridge 3. Main bottom surface 4
Is inclined, and the ridge 3 is provided on the higher side of this inclination.

The height of the ridges 3 (the rising height from the bottom of the liquid reservoir 5) is preferably about 1 to 50 mm. The bottom surface of the liquid reservoir 5 is flat.

The cavity 2 of the lower mold 1 has a concave shape surrounded by the main bottom surface 4, the liquid reservoir 5 and the cavity side surface 11. However, the cavity of the lower mold 1 is not limited to this, and may have any shape. The cavities can be of various concave, convex or flat shapes.

A process for forming a vehicle seat pad using this mold will be described below.

First, as described above, a stock solution (a urethane stock solution in this embodiment) 6 for molding a low-density foam is supplied to the high side of the main bottom surface 4 (near the ridges 3) through the nozzle 7. . This undiluted solution 6 flows down along the inclination of the main bottom surface 4,
Wet the entire main bottom surface 4. The undiluted solution 6 immediately starts foaming, and swells upward from the main bottom surface 4 so as to increase in thickness to become a low-density foam 6a.

After the foaming of the stock solution 6 has progressed to some extent, the stock solution 9 for molding the high-density foam is supplied from the nozzle 8 to the solution reservoir 5. Then, the upper mold 10 is covered and fixed to the lower mold 1.
This stock solution 9 also immediately starts foaming and becomes a high density foam 9a. As shown in FIG.
To the upper side of the low-density foam 6a in the cavity 2 and expands, and eventually fills all the remaining space of the cavity 2. The high-density foam 9a is in close contact with and integrated with the low-density foam 6a.

After that, the molded product is removed from the mold and turned upside down to obtain the vehicle seat pad 12 shown in FIG. The upper side of the vehicle seat pad 12 is an upper layer portion made of low hardness low density foam 6a, and the lower side is a lower layer portion made of high hardness high density foam 9a. By selecting the supply amounts of the stock solutions 6 and 9 and the supply timing of the stock solution 9 to the lower mold 1, the low-density foam 6a has a specified thickness. As described above, since the undiluted solution 6 spreads along the inclined main bottom surface 4 so as to wet the whole main bottom surface 4, the seat surface of the seat pad 12 is entirely formed of the low-density foam 6a. The surface facing the liquid reservoir 5 is made of high density foam 9a, which is arranged at the rear end of the seat pad on the rear side.

In this way, the vehicle seat pad 12 can be manufactured by one molding operation using one mold, and the production efficiency is remarkably high.

Although not shown, a mounting member for mounting the seat on the vehicle body is arranged in the mold and integrally molded.

In the vehicle seat 1 thus manufactured, the low-density foam 6a (polyurethane foam) constituting the upper layer portion has a 25% ILD hardness (ISO2439).
-1997) is 60 to 300 N and has a density of 20 to 80 kg.
/ M ³ is preferable.

Even if this 25% ILD hardness is less than 60 N, it exceeds 300 N and proper cushioning properties cannot be obtained.
It becomes uncomfortable to sit on. Similarly, for density 2
If it is less than 0 kg / m ^{3 or more} than 80 kg / m ³ , appropriate cushioning properties cannot be obtained, and the sitting comfort becomes poor.

On the other hand, the high density foam (polyurethane foam) 9a forming the lower layer has a 25% ILD hardness of 300.
It is preferably N or more, and particularly preferably 1000 to 5000N. That is, the lower layer is required to have a certain degree of hardness to secure the strength and rigidity of the seat.
The LD hardness is preferably 300 N or higher, and particularly preferably 1000 N or higher. However, if the hardness is excessively high, the weight becomes heavy. Therefore, the 25% ILD hardness is preferably 5000.
N or less.

In the above embodiment, the main bottom surface 4 is made of a smooth surface as a whole, but in the present invention, as in the lower mold 1A of FIG. 3, the main bottom surface 4 is provided with the convex portion 13 extending in the tilt direction and the intersecting direction. May be. By providing this convex portion 13, it is possible to reduce the difference in reactivity caused by the time difference when the main bottom surface 4 is wetted by the undiluted solution, or to spread the undiluted solution 6 as uniformly as possible over the entire main bottom surface 4.

[0025]

As described above, according to the present invention, a vehicle seat pad can be efficiently manufactured by a single molding operation.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a method of manufacturing a vehicle seat pad according to an embodiment.

FIG. 2 is a cross-sectional view of a vehicle seat pad manufactured by the method of FIG.

FIG. 3 is a sectional view of a lower mold used in another embodiment.

[Explanation of symbols]

1,1A lower mold 2 cavities 3 convex stripes 4 main bottom 5 liquid reservoir 6 Low Density Foam Stock Solution 6a Low density foam 9 Stock solution for high density foam 9a high density foam 10 Upper mold 12 Vehicle seat pad 13 convex

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B68G 11/04 B68G 11/04 // B29K 105: 04 B29K 105: 04 B29L 31:58 B29L 31:58 F term (reference) ) 3B096 AB07 AD07 4F202 AB02 AG03 AG20 AH26 CA01 CB01 CB22 CK06 4F204 AG03 AG20 AH26 EA01 EB01 EB21 EB22 EF01 EF27 EF49 EK24

Claims (8)

[Claims] 1. A method for producing a vehicle seat pad having an upper layer portion made of a low-density foam and a lower layer portion made of a high-density foam by using a mold, wherein the mold is a vehicle seat pad. A cavity surrounded by a bottom surface of the cavity corresponding to the seat surface of the vehicle and a side surface of the cavity corresponding to the side surface of the vehicle seat pad, and one end of the bottom surface of the cavity is a liquid reservoir for storing a high-density foam stock solution. Is provided, and the low-density foam stock solution is supplied to the bottom surface of the cavity other than the liquid storage section to foam the same to form the low-density foam, and the high-density foam stock solution is stored in the liquid storage section. Is supplied to cause foaming, and a high-density foam is formed from the liquid reservoir to the upper side of the low-density foam to produce a vehicle seat pad. 2. The method for manufacturing a vehicle seat pad according to claim 1, wherein the bottom surface of the cavity other than the liquid reservoir is inclined. 3. The method for manufacturing a vehicle seat pad according to claim 2, wherein the liquid reservoir is arranged at an end of the inclined bottom surface of the cavity on the high level side. 4. The low-density foam stock solution according to claim 2, wherein the low-density foam stock solution is supplied to a portion of the bottom surface of the cavity other than the liquid reservoir, and the low-density foam stock solution is caused to flow down along an inclination. A method for manufacturing a vehicle seat pad, which is characterized. 5. The low-density foam stock solution according to claim 4, wherein the low-density foam stock solution is supplied so that the entire bottom surface of the cavity other than the liquid reservoir is wetted by the low-density foam stock solution. Production method. 6. The vehicle seat pad according to claim 2, wherein the liquid reservoir and a cavity bottom face adjacent to the liquid reservoir are partitioned by a ridge. Manufacturing method. 7. The height of the ridge according to claim 6,
A method for manufacturing a vehicle seat pad, which is 50 mm. 8. The vehicle according to any one of claims 2 to 7, characterized in that a convex portion extending in a direction intersecting with the inclination direction is provided on the bottom surface of the cavity other than the liquid reservoir. Seat pad manufacturing method.