JPS634912A - Molding of urethane seat pad - Google Patents

Abstract

PURPOSE:To prevent the material of pad from turning round to spread on the side surface of a preformed pad member, by a method wherein the whole periphery of the side surface of the pad member is held in a condition that the same is pressed by the inner surface of a mold against a contacting surface of the pad member and the material of pad, when the pad member is arranged into the mold. CONSTITUTION:A top force 3 is incorporated into a bottom force 6, in which a pad member 5 is arranged. The thickness of the pad member 5 is increased by a slub urethane 2, therefore, the inner surface of the top force 3 is pressed against the upper surface of the pad member 5 and, further, interference stocks 3a, 3b, provided on the inner surface of the top force 3, are pressed against the pad member 5, therefore, the pad member 5 is held in a compressed condition surely in the whole periphery of the side surface thereof. The inner surface of the mold is pressed against the whole periphery of the side surface of the pad member 5 from the time of the pouring of the pad material to the curing thereof, and the material of the pad contacts only with the contacting surface 8 of the pad member 5, therefore, the material of the pad is prevented surely from turning round to spread on the side surface of the pad member 5, accordingly, the generation of fins on the side surface of the pad member 5 is also eliminated. The material of the pad is impregnated on the contacting surface 8, and the material of the pad is bonded to the pad member 5 due to the curing of the material of the pad.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a seat pad used for vehicle seats, etc., which is provided with portions of different hardness in order to improve the ability to hold the human body during cornering. The present invention relates to a method for molding a urethane sheet pad.

As is well known in the art, soft urethane foam A is used as a vehicle seat.
Cushion pads made of rubber are often used.

By the way, in recent years, there has been a growing trend toward higher-quality vehicle seats, such as improved holdability during cornering,
There is a demand for high-quality interiors, for contributing to sophisticated design and three-dimensionality, and for multi-functionality. In order to ensure a seat structure and high quality that meet these demands, it is considered advantageous to adopt a seat pad with different hardness in which desired parts of the urethane seat pad have different hardness. Various methods have been developed and introduced for shaping.

For example, as a conventional method for molding seat pads with different hardness, the first method is to integrally mold materials with different hardness by dividing them into one mold and injecting them.
Second, a pre-molded urethane pad member is placed in a part of the mold, and the pad material is injected into this mold.
A molding method is known in which a urethane pad member is foamed and hardened and a pad material hardened in a mold is made to have different hardness.

This second method will be explained based on FIGS. 6 to 9.

A high-hardness pad member 5 is formed in advance in a separate mold,
The pad member 5 is charged and placed in the lower mold 6, and then the upper mold 7 is installed. At this time, the pad member 5 is brought into close contact with the inner surfaces of the lower mold 6 and the upper mold 7, leaving a contact surface 8 with the pad material. Furthermore, a pad material is injected into the cavity of the mold, foamed, and hardened.

A seat pad having different hardness portions is manufactured by forming a high hardness portion using the above-mentioned pad member and forming a low hardness portion using a hardened portion of the pad material.

Problems to be Solved by the Invention However, each of the above conventional methods has advantages and disadvantages, and in the second method, although the pre-formed pad member is brought into close contact with the inner surface of the mold, it is not completely It is difficult to obtain a close contact state, and the pad material wraps around not only the interface between the pad member and the pad material but also the side surface of the pad member, and is impregnated into the inside of the pad member from the surface. After the pad material hardens, the impregnated part tends to have an abnormal hardness instead of the original hardness of the pad material, leading to quality deterioration.Also, the problem is that the quality is unstable because it depends on how the pad material wraps around. There is. In addition, the padding material that has wrapped around the side of the padding member may remain as flakes after curing, and this paris is partially impregnated with the hard padding material, so it is relatively hard and causes flaking. When such a seat pad is used as a vehicle seat, the pads become convex highlight lines, which not only causes the above-mentioned abnormal hardness but also causes a further problem of deterioration of product quality.゛The basic purpose of this invention is to solve the above-mentioned problems, and when the pad material is foamed and cured, the pad material is prevented from wrapping around the side surface of the pre-formed pad member.
To provide a method for molding a urethane sheet pad that has excellent quality and is stable in quality.

Means for Solving the Problems In other words, the method of molding a urethane sheet pad of the present invention involves inserting and arranging a preformed pad member into seven parts of a mold, and foaming the pad material injected into the mold. , harden, let me-
In the method for molding a urethane sheet pad in which a foreign part is provided in the part, when placing the pad member in the mold, the side surface of the pad member against the contact surface between the pad member and the 15-piece material is molded around the entire circumference. It is characterized by being held in a compressed state by the inner surface.

According to this invention, the pad member formed in advance is held in a compressed state by the inner surface of the mold over the entire circumference of the side surface. The pad member generates an expansion force against this compression force due to its elastic force, and the side surface of the pad member is directly or indirectly pressed against the inner surface of the mold over the entire circumference. This prevents the pad material from curling around from the outer peripheral side of the contact surface with the pad member to the side surface of the pad member, providing stability in hardness and preventing the occurrence of flakes.

Embodiments Next, eleven embodiments of the present invention will be explained based on FIGS. 1 to 5.

In this example, structures similar to those of the conventional example are denoted by the same reference numerals, and the explanation thereof will be omitted or simplified.

A coarse wool felt 1 is incorporated into a high-hardness pad member 5 formed in advance using a separate mold, and a slab urethane 2 is attached to the upper ring of the rough pad member 5 as an intermediate member. Further, a boundary surface 8 of the pad member 5 with a pad material, which will be described later, is inclined with respect to the contact direction so as to increase the contact area with the pad material. The aforementioned coarse felt 1 and slab urethane 2 are provided so as to protrude from this interface 8.

This pad member 5 is inserted into the lower mold 6 and placed.

Note that interference margins 3a and 3b are provided on the inner surface of the upper part of the upper mold 3 and in contact with the pad member 5 disposed on the lower mold 6 so as to press against the pad member 5. 〇 − It is done.

That is, the inner surface of the upper mold 3 protrudes from the inner surface of the conventional upper mold 7, which is designed to match the shape of the pad member 5, in a direction that reduces the volume of the mold cavity.

The upper mold 3 is assembled to the lower mold 6 into which the pad member 5 is inserted. Since the thickness of the pad member 5 is increased by the slab urethane 2, the inner surface of the upper mold 3 is pressed against the upper surface of the pad member 5, and the interference types 3a and 3b provided on the inner surface of the upper mold 3 are Since it comes into pressure contact with the member 5, the pad member 5
is reliably maintained in a compressed state over the entire circumference of the side surface. The pad member 5 has an elastic force, and the entire circumference of the side surface of the pad member is pressed against the inner surface of the mold directly or via the slab urethane 2 due to the elastic force that resists the compressive force.

A pad material is injected into the cavity of the mold thus assembled, and is foamed and hardened.

Until the pad material is injected and cured, the inner surface of the mold is in pressure contact with the side surface of the pad member 5 over the entire circumference, and the pad material only contacts the contact surface 8 of the pad member 5. It is reliably prevented from going around to the side surfaces of the pad member 5, and therefore no flaking occurs on the side surfaces of the pad member 5. The contact surface 8 is impregnated with a pad material, and as the pad material hardens, the pad member 5 and the pad material are bonded together.

Further, the coarse felt 1 provided on the upper surface of the pad member 5
The - part is included in the pad material, and the pad material hardens in that state, so the ends of the coarse wool felt 1 are fixed to the pad member 5 and the hardened pad material, respectively. The adhesion with the pad material becomes stronger.

Note that the slab urethane 2 also has the same effect of improving adhesiveness.

This improved adhesion eliminates the problems that conventionally occurred during demolding, such as peeling and tearing of parts of different hardness at boundaries, improving yields and eliminating the work required for repairs. Work efficiency will also improve.

In addition, in this example, the slab urethane was placed as an intermediate member between the inner surface of the mold and the pad member, but the placement location of the intermediate member is not limited to the position of the above example, and the intermediate member may be placed as an intermediate member. The pad member may be held in a compressed state directly by the inner surface of the mold without intervening. In short, any mold may be used as long as it can reliably hold the side surface of the pad member in a compressed state over the entire circumference.

In addition, in this example, a pad member with high hardness was used to provide a foreign part in a part, but it is also possible to use a pad member made of an appropriate material to obtain desired characteristics. .

As described in detail, according to the present invention, when the pad member is placed in the mold, the entire circumference of the side surface of the pad member relative to the contact surface between the pad member and the pad material is held in a compressed state by the inner surface of the mold. □Since I decided to do it, I foamed and hardened the pad material.
During this process, the padding material does not wrap around the sides of the padding member, and is completely blocked by the boundary, which prevents variations in hardness and the occurrence of flakes, making it possible to efficiently produce seat pads with high quality and stable quality. There is an effect that manufacturing is a monkey.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an embodiment of the present invention, Fig. 2 is a perspective view of a pad member incorporating coarse felt, Fig. 3 is a cross-sectional view taken along the line ■-■ in Fig. IV-IV in Figure 1
5 is a schematic diagram with the mold in FIG. 3 omitted, FIG. 6 is a schematic diagram showing a conventional example, FIG. 7 is a perspective view of a pad member in the conventional example, and FIG. Figure 9 is a cross-sectional view taken along the line ■-■ with the mold omitted, and Figure 9 is IX in Figure 6.
- IX line cut diagram. 1... coarse wool felt, 2... slab urethane, 3...
... Upper mold, 5... Pad member, 6... Lower mold, 7
... Upper mold, 8... Contact surface.

Claims (1)

[Claims] Inserting and arranging a preformed pad member into a part of a mold,
In this method of forming a urethane sheet pad in which the pad material injected into the mold is foamed and cured to form a foreign part in a part, when the pad member is placed in the mold, the contact surface between the pad member and the pad material is A method for molding a urethane sheet pad, characterized by holding the side surface of a pad member in a compressed state over the entire circumference by the inner surface of a mold.