BACKGROUND OF THE INVENTION1. Field of the Invention[0001]
The present invention relates to a vehicle seat and a method of manufacturing the same, and particularly, it relates to a lightweight seat, which can easily form an innovative and exquisite design and can be readily recycled, and a method of manufacturing the same.[0002]
2. Description of the Related Art[0003]
A vehicle seat in general has a seat cushion and a backrest. Both of the seat cushion and the backrest consist of frames having given forms, a cushioning material made of urethane foam which covers the frame and supports either a hip or a back of a passenger, and a skin material which covers these frames and the urethane foam cushioning material.[0004]
The aforementioned vehicle seat is made by coating the frames with the urethane foam cushioning material and, thereafter, covering with the skin material. In addition, the seat cushion and the backrest need to be joined with each other since they are separately formed. Especially when the seat has a mechanism for reclining the backrest, the reclining mechanism is covered by a reclining cover.[0005]
As mentioned above, both the seat cushion and the backrest consist of many parts such as a frame, urethane foam cushioning material, and a skin material. Since these parts need to be assembled, many manufacturing processes are required for manufacturing the vehicle seat. In the process of applying the skin material, covering the urethane foam cushioning material with the skin material is a troublesome task since the skin material is difficult to slip over the cushioning material.[0006]
For example, when the urethane foam cushioning material is covered with the skin material by means of a machine, considerable force is required because the skin material does not slip over the cushioning material easily. As the result, the urethane foam cushioning material is deformed and the state of covering lacks in uniformity, and even worse, the shoulder portion gets flaggy. As the shoulder portion gets flaggy, surplus skin material may be caused at the bottom part, which may lead to occurrence of wrinkles or slacks.[0007]
Furthermore, it is difficult to create exquisite or distinctive design since the shape of the urethane foam cushioning material is obscured by the skin material as the result of covering the urethane foam cushioning material with the skin material. In order to solve the foregoing problems and to improve commercial value, it is necessary to form the urethane foam cushioning material in a special shape or to fit a part of the skin material in the urethane foam so as to be able to adjust the shape of the seat, as described in Japanese unexamined utility model publication No. 1-124200.[0008]
In addition, the vehicle seat is not readily separated for recycling since the vehicle seat consists of many parts from various materials such as the frame, the urethane foam cushioning material and the skin material, which is a disadvantage in view of recycling efficiency.[0009]
Since the seat cushion and the backrest are separately formed, the levels of the seat cushion and the backrest on the side faces are uneven when they are joined with each other. That is a restriction in making design of the vehicle seat. In the meantime, a cover for the reclining mechanism is required when the seat has a reclining mechanism, with which the backrest reclines against the seat cushion.[0010]
Therefore, it is an object of the present invention to provide a vehicle seat, which can easily form an innovative and exquisite design and can be readily recycled by using a foam as an exterior material, and a method of manufacturing the same.[0011]
It is another object of the present invention to provide a vehicle seat, which can be manufactured without a skin material, can directly form a concave/convex shape, and can decrease its weight by performing an integral molding with using the foam as an exterior material in a mold, and a method of manufacturing the same.[0012]
It is a further object of the present invention to provide a vehicle seat, which uses foam as an exterior material, so as to be able to make the side faces of the seat cushion and the backrest at an identical level, and at the same time eliminates the need for a cover which covers the reclining mechanism and expand the flexibility of its design, and a method of manufacturing the same.[0013]
SUMMARY OF THE INVENTIONAccording to the present invention, a vehicle seat has at least a sitting area and a seat cushion for supporting the sitting area in which the seat cushion is formed from foam as an exterior material in a given form.[0014]
Since the foam is used as the skin material and the shape of the exterior material is not obscured by a skin material, the exterior material becomes an outward appearance so as to be able to create exquisite and innovative design. Because the skin material is not used, it is also possible to manufacture at a lower cost as well as to provide a lightweight seat.[0015]
In the vehicle seat of the present invention having at least a sitting area and a seat cushion for supporting the sitting area, the seat cushion is formed from the foam as an exterior material in a given form and has a pad in the sitting area. Preferably, the seat cushion has a concave portion to which the pad is disposed.[0016]
When a pad is disposed in above-mentioned manner, desired shape, material, and color of the pad may be obtained so as to expand the flexibility of design and provide an innovative vehicle seat.[0017]
The foam forming the seat cushion may be one selected from the group consisting of PP (polypropylene) bead foam, PE (polyethylene) bead foam, PP foam, PE foam, AS resin(acrylonitrile-styrene resin) foam, EVA (ethylene-vinyl acetate copolymer resin) foam and urethane foam. PP bead foam with superior weather resistance is preferably used, PE bead foam is cheap, EVA foam and urethane foam is very flexible, thus it is possible to expand the flexibility of design according to different materials which have been selected.[0018]
According to the present invention, a vehicle seat has at least a seat cushion for supporting a sitting area and a backrest for supporting a back area in which the seat cushion and the backrest are formed from foam as an exterior material in a given form. In this manner, the side faces of the seat cushion and the backrest are formed on an identical face so as to be able to form the seat cushion and the backrest as a unit.[0019]
In addition, a vehicle seat of the present invention having at least a seat cushion for supporting a sitting area and a backrest for supporting a back area, in which the seat cushion and the backrest are formed from foam as an exterior material in a given form and have pads in the sitting area and the back area. Preferably, the sitting area of the seat cushion and the back area of the backrest have concave portions to which the pad is disposed. When a pad is disposed in above-mentioned manner, desired shape, material, and color of the pad may be obtained so as to expand the flexibility of design and provide an innovative vehicle seat.[0020]
The foam forming the seat cushion and the back rest may be one selected from the group consisting of PP (polypropylene) bead foam, PE (polyethylene) bead foam, PP foam, PE foam, AS resin(acrylonitrile-styrene resin) foam, EVA (ethylene-vinyl acetate copolymer resin) foam and urethane foam.[0021]
In addition, the seat cushion and the backrest are preferably made by inserting a frame and performing an integral foaming. Here, the surface of the foam is treated, preferably with grain patterns. A reclining device, which reclines the backrest, is preferably covered with foam as an exterior material. A boundary of the side faces of the seat cushion and said backrest is preferably a flat surface as an identical face.[0022]
In above-mentioned means of formation, the reclining mechanism (reclining device) can be disposed inside the foam as an exterior material when the backrest reclines against the seat cushion so as to be able to eliminate the use of a reclining cover, to eliminate the necessity of having a large number of employees for the assembly work of the seat cushion and the backrest and to design a seat in which the seat cushion and the backrest is formed integrally.[0023]
According to the present invention, the foam resin is integrally molded on frames, the exterior material of the seat cushion including the sitting area and the backrest for supporting the back is formed by using the foam, and then other pads are disposed in the sitting area and the back area.[0024]
In addition, according to the present invention, the foam resin is integrally molded on frames, the seat cushion including the sitting area and the backrest for supporting the back are formed by using the foam, and then other pads are disposed in the sitting area and the back area.[0025]
Here, concave portions are formed in the sitting area and the back area, and pads which fits the concave portion are disposed thereto. The integral mold of foam resin on the frame is performed by filling the foam resin into the mold, in which the frame is inserted beforehand. A cavity side of the mold is preferably a side to create grain patterns on exposed part of the seat cushion and the backrest.[0026]
The integral mold in the mold can be performed so as to be able to provide a vehicle seat in which concave/convex shapes of the foam are expressed directly, and also provide a lightweight seat, by following above-mentioned manner.[0027]
In above-mentioned manner and according to the vehicle seat of the present invention, one or all of the seat cushion, the backrest and the headrest are formed from the foam as an exterior material, and the shape of the foam expresses a shape formed by a mold without any change. As these components can be integrally molded in a mold and use no skin material, a concave/convex shape of the foam becomes their outward appearances without any change.[0028]
In addition, since the foam is used as an exterior material, no skin material is required. Therefore, it is readily separated for recycling, and thus it has high recycling efficiency.[0029]
Since the foam without being changed is used, it is possible to manufacture at a lower cost and to provide a lightweight seat. At the same time, it is possible to provide a vehicle seat with better shape and design by adding, for example, a pigment so as to apply color. When the seat has a reclining function for reclining the backrest, the boundary of the backrest and the seat cushion on the side faces is flat at an identical level so as to expand the flexibility of its design.[0030]
In addition, using bead foam as the foam may improve shock absorption. The whole frame is coated with the bead foam and, thus, absorbs shocks from every direction, which improves safety.[0031]