JP3663009B2 - Cushion material molding method - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for molding a cushion material used for a vehicle seat, a furniture seat, and the like.
[0002]
[Prior art]
In general, when a cushion material for a vehicle seat is molded, cotton made of a resin such as polyester is molded as follows. That is, as shown in FIG. 7, first, cotton W is filled into the recess 1 a of the lower mold 1. Next, as shown in FIG. 8, the lower mold 1 and the upper mold 2 are closed so that the protrusion 2a of the upper mold 2 enters the recess 1a to a predetermined depth. Thereby, the cavity 3 is formed between the lower mold 1 and the upper mold 2 and the cotton W is pressurized to fill the cavity 3 with a predetermined density. Next, after the cotton W is heated to partially melt it, it is solidified. Then, a part of the melted cotton W fixes the fibers of the cotton W together. Thereby, the whole cotton W is shape | molded by the cushion material which has a desired shape.
[0003]
[Problems to be solved by the invention]
In the above molding method, when the cotton W is filled in the concave portion 10a of the lower mold 10, the cotton W has a large volume, and even if it is compressed, it returns to its original size when the constraint is released. Therefore, there is a problem that much time and labor are required for filling.
[0004]
Further, in a state in which the recessed portion 1a is filled with the cotton W, many portions of the cotton W protrude from the recessed portion 1a to the outside. In order to prevent the protruding cotton W from being sandwiched between the lower mold 1 and the upper mold 2 when the mold is closed, careful attention and labor are required when the mold is closed. As a result, there is a problem that work efficiency is lowered.
[0005]
In addition, when the surface shape of the cushion material is complicated, for example, as shown in FIG. 9, when the small concave portions 1b and 1c are formed on the bottom surface of the concave portion 1a corresponding to the surface shape of the cushion material. It is difficult to sufficiently fill the small recesses 1b and 1c with cotton W. For this reason, there existed a problem that it was difficult to shape | mold the cushion material of a desired shape correctly.
[0006]
[Means for Solving the Problems]
The invention according to claim 1 is made in order to solve the problems of the former two, and fills a cavity formed between a pair of molds with cotton and heats the cotton to melt a part thereof. In the method of forming a cushioning material by cooling and solidifying, instead of filling the cotton directly into the cavity, the cotton is packed in a bag made of a resin having a lower melting temperature and then evacuated. The pack body is sealed, and the pack body is placed in the cavity.
When inserting the pack body into the cavity, as in the invention according to claim 2, the pack body may be inserted so that the filling amount of cotton in the cavity is different in each part of the cavity. In this case, a plurality of the pack bodies are used as in the invention according to claim 3, and a different number of pack bodies are arranged in each part in the cavity, or, as in the invention according to claim 4, By using a plurality of pack bodies having different packing capacities and arranging each pack body in each part of the cavity, the filling amount of cotton in the cavity can be made different in each part of the cavity.
Further, when using a plurality of pack bodies, as in the invention according to claim 5, at least one pack body may be packed with cotton having higher hardness than cotton packed in other pack bodies. Good.
Further, as in the invention according to claim 6, by using a plurality of the pack bodies and forming at least one of the plurality of pack bodies smaller than the other pack bodies, the above three problems can be solved at once. can do.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS.
First, an embodiment of the present invention will be described with reference to FIGS. 1 to 3. This embodiment is a case where the shape of a cushion material to be molded is relatively simple.
[0008]
In carrying out the molding method of the present invention, a mold A is used as shown in FIG. As the mold A, the same mold as that used in the conventional molding method can be used. Here, a mold A comprising a lower mold (one mold) 10 having a recess 10a and an upper mold (the other mold) 20 having a protrusion 10b fitted into the recess 10a is used. For the lower mold 10 and the upper mold 20 of the mold A, those made of a porous material or those having a large number of small holes are used so that the cotton W can be heated with a heated gas in a heating step described later. desirable.
[0009]
Moreover, although it is the cotton W used as the raw material of a cushioning material, the cotton W can be arbitrarily selected as long as the fiber melts when heated to an appropriate temperature, for example, 120 to 150 ° C. . Here, cotton W made of a resin such as polyester or polypropylene is used. In the case of the cotton W made of such a resin, the whole can be melted, but only a part of the cotton W may be melted. For example, blended cotton obtained by mixing natural cotton with cotton made of the above resin may be used.
[0010]
Next, a cushion material is formed using the above-described mold A and cotton W. In the method of the present invention, the cotton W is packed in the bag 40 without directly filling the cavity 30 of the mold A with the cotton W. The formed pack body 50 packed in the cavity 30 is inserted into the cavity 30.
[0011]
As a material of the sheet constituting the bag 40, any material can be used as long as it melts at a temperature lower than that of the cotton W. Here, a low melting point resin such as polyethylene or polyamide is used. Moreover, it is desirable to make the sheet constituting the bag 40 as thin as possible, and here, the sheet is formed into a film having a thickness of several μm using the above-described material. And the bag 40 which the one side part opened by this film is formed.
[0012]
As shown in FIG. 2, cotton W is packed in the bag 40 configured as described above. At the time of filling, a block body having a large cotton W is formed as shown in FIG. 3, and an appropriate amount is cut out from the block body as indicated by an imaginary line in the drawing. And if this is packed in the bag 40, packing operation can be performed comparatively easily. Further, in this embodiment, only one pack body 50 is inserted into the cavity 30 so that the cotton W is packed in the same amount as that required for molding the cushion material. However, when N pieces of a plurality of pack bodies 50 having the same size are uniformly inserted into the cavity 30, the amount is set to 1 / N of the amount when one piece is inserted.
[0013]
After the bag 40 is filled with a predetermined amount of cotton W, the air in the bag 40 is vacuumed. Then, the opening part of the bag 40 is sealed and the pack body 50 is obtained.
When vacuum suction of the bag 40 is performed, for example, a part of the opening of the bag 40 is left and the other part is sealed. Next, the tip of a tube connected to a vacuum suction means such as a vacuum suction pump is inserted into the bag 40 from the remaining opening. In this case, it is preferable to make the tip of the inserted tube flat. Then, the vacuum suction means may be activated to vacuum suck the bag 40. When the inside of the bag 40 is vacuum-sucked, not only the air in the bag 40 but also the air present in the cotton W is discharged to the outside. As a result, the volume of the bag 40 is larger than the initial volume in which the cotton W is packed. Significantly smaller. When the vacuum suction is finished, the remaining opening is sealed. The opening can be sealed by fixing the sheets forming the opening by means such as heat fusion.
[0014]
When the pack body 50 is formed as described above, the pack body 50 is inserted into the recess 10a of the lower mold 10 as shown in FIG. In this case, since the volume of the cotton W is reduced by being packed in the bag 40 and vacuumed, it can be loaded very easily as compared with the case where the cotton W is directly filled. Further, since a predetermined amount of cotton W is packed in the pack body 50, the predetermined amount of cotton W can be accurately and extremely easily filled into the recess 10a simply by inserting the pack body 50 into the recess 10a. be able to.
[0015]
Thereafter, the protrusion 20a of the upper mold 20 is fitted into the recess 10a to a predetermined depth. At this time, since the volume of the pack body 50 is significantly smaller than that of the cotton W in the natural state, the pack body 50 does not protrude from the recess 10a. Therefore, it is possible to easily prevent a part of the pack body 50 from being sandwiched between the lower mold 10 and the upper mold 20.
[0016]
Next, the pack body 50 is heated. When the lower mold 10 and the upper mold 20 of the mold A are formed of a porous material or have a large number of small holes, the pack body 50 is heated with heated air or This can be done by introducing a heated gas such as heated steam. For example, as shown in FIG. 1B, the heated gas is introduced into the cavity 30 from the lower mold 10, and the heated gas introduced into the cavity 30 is discharged from the upper mold 20 to heat the pack body 50. be able to. Of course, a heater may be embedded in the walls of the lower mold 10 and the upper mold 20 and heated by this heater. However, the heating with the heated gas can heat the pack body 50 and the cotton W more uniformly. Therefore, it is desirable to use heated gas. Of course, the temperature of the heated gas should be higher than the melting temperature of the cotton W.
[0017]
When the pack body 50 is heated, since the melting temperature of the bag 40 is lower than the melting temperature of the cotton W, the bag 40 is first melted. Then, the cotton W in the bag 40 swells and fills the cavity 30 in a pressurized state. If the heated gas is further supplied in this state, the surface layer portion of the fibers constituting the cotton W is melted. When this state is reached, the heating of the cotton W is stopped. Then, the molten resin is solidified. Then, the solidified resin fixes the fibers of cotton W together. As a result, a cushion material having a predetermined shape is formed from the cotton W.
[0018]
A part of the melt produced by melting the bag 40 is discharged to the outside together with the heated gas, a part adheres to the fibers of the cotton W and contributes to the fixing of the fibers, and the remaining part is the bottom. It accumulates in the bottom of the recess 10a of the mold 10 and solidifies. The amount of the solidified product is very small and becomes a thin film, so that it hardly affects the shape of the cushion material.
[0019]
Next, another embodiment of the present invention will be described.
In the embodiment shown in FIG. 4, a plurality of pack bodies 50 having the same size are used, and three pack bodies 50 are arranged on both sides of the cavity 30 so as to overlap each other. The two pack bodies 50 are arranged so as to overlap each other, and the number of the pack bodies 50 is increased on both sides. The pack body 50 is formed in the same manner as the pack body 50 of the above embodiment. This also applies to the embodiments described below.
[0020]
After arrange | positioning as mentioned above, the pack body 50 is heated and the bag 40 of each pack body 50 is fuse | melted. As a result, the cotton 30 is filled into the cavity 30. In this case, since a larger number of pack bodies 50 are arranged on both sides of the cavity 30 than on the central part, both sides of the cavity 30 are filled with a larger amount of cotton W than on the central part, and the density becomes higher. Therefore, the density of the cotton W in both sides also increases in the molded cushion material, and the hardness of both sides becomes higher than that in the center. That is, it is possible to achieve a different hardness of the cushion material. Of course, the portion where the hardness is increased can be changed according to the purpose of use of the cushion material. For example, the hardness of the central portion may be higher than that of the both sides.
[0021]
Further, the embodiment shown in FIG. 5 shows another example for achieving different hardness of the cushion material, and two types of pack bodies 50A and 50B are used. The pack body 50A is packed with an amount of cotton W equal to the total amount of cotton W packed in the three pack bodies 50 arranged on both sides of the cavity 30 of the embodiment shown in FIG. On the other hand, the pack 50B is packed with an amount of cotton W equal to the total amount of the cotton W packed in the two packs 50 arranged at the center of the cavity 30 of the embodiment shown in FIG. Therefore, the thickness of the pack body 50A (the dimension of the recess 10a in the depth direction) is thicker than the pack body 50B.
[0022]
When a plurality of pack bodies 50 are used, it is possible to achieve a different hardness of the cushion material by stuffing at least one pack body 50 with cotton having a higher hardness than cotton stuffed into other pack bodies 50.
For example, in the case of the embodiment shown in FIG. 4, high-hardness cotton W (for example, blended cotton) is packed in the pack body 50 disposed on both sides of the cavity 30 and disposed in the center of the cavity 30. The pack body 50 is packed with low-hardness cotton (for example, polyester cotton). In this way, since both sides of the cushion material are formed of cotton W having a high hardness and the center portion is formed of cotton W having a low hardness, it is possible to achieve a different hardness of the cushion material. In particular, by combining the arrangement number of the pack body 50 with the embodiment shown in FIG. 4 in which each part of the cavity 30 is changed, further different hardness of the cushion material can be achieved. This also applies to the embodiment shown in FIG.
[0023]
Further, the embodiment shown in FIG. 6 is suitable when the surface shape of the cushion material to be molded is complicated and the bottom surface of the recess 10a has a correspondingly complicated shape. A small recess 10b corresponding to the surface shape of the cushion material and a smaller recess 10c smaller than this are formed on the bottom surface. Moreover, the convex part 10d is formed between the small recessed parts 10b and 10c.
[0024]
And in order to shape | mold accurately the cushion material which has the surface shape corresponding to the bottom face of the recessed part 10a which carried out the complicated shape, in this Example, four types of pack bodies 50C-50F from which a magnitude | size mutually differs are used. . Each of the pack bodies 50C and 50D is formed with a size and a shape such that a part of each pack body enters the small recesses 10b and 10c with almost no gap. Further, the pack body 50E is packed with an amount of cotton W that can fill the space of the cavity 30 above the convex portion 10d without excess or deficiency. Furthermore, the pack body 50 </ b> F is packed with an amount of cotton W that can be filled in the remaining space of the cavity 30 without excess or deficiency. Of course, the total amount of the cotton W packed in each of the pack bodies 50C to 50F is set in advance so as not to be excessive or insufficient for molding the cushion material.
[0025]
When a cushion material is molded using the pack bodies 50A to 50D, the pack bodies 50A to 50D are respectively arranged at predetermined positions shown in FIG. 4 of the recess 10a. Next, the lower mold 10 and the upper mold 20 are closed. Then, each pack 50A-50D is heated with heated gas, and each bag 50 is melted. Then, the cotton W packed in each pack body 50A-50D swells. At this time, since the pack bodies 50A and 50B are fitted in the small recesses 10b and 10c, the cotton W inside each is reliably filled in the small recesses 10b and 10c. Therefore, a cushion material having a complicated shape can be molded with high accuracy.
[0026]
In this embodiment, a cushion material having a uniform hardness in each part is molded. However, in combination with the above-described example, a cushion material having a different hardness can be molded in each part. It is. For example, a large number of pack bodies are arranged at the positions where the small concave portions 10b and 10c are formed, or a large number of pack bodies are used instead of the pack body 50F, and the number of arrangement of the pack bodies is changed in each part of the cavity 30. Thus, it is possible to achieve a different hardness of the cushion material.
[0027]
【The invention's effect】
As described above, according to the first aspect of the present invention, the pack body formed by packing cotton into a bag and vacuum-sucking is used. small. Therefore, the pack body can be easily inserted into the cavity. Moreover, when the pack body is inserted into the recess of the lower mold, it does not protrude from the recess, and the pack body is not sandwiched between the lower mold and the upper mold. Therefore, an effect that the mold closing operation can be easily performed is obtained.
Moreover, according to the invention which concerns on Claim 2, 3, 4 or 5, in addition to said effect, the effect that the different hardness of a cushion material can be achieved is acquired.
Further, according to the invention according to claim 6, since plural kinds of pack bodies having different sizes are used, the details are filled with cotton by inserting small pack bodies into the details of the recesses. As a result, it is possible to obtain a cushioning material with good shape accuracy.
[Brief description of the drawings]
FIG. 1 shows a cross-sectional view of an example of a forming die used in the forming method of the present invention, and FIG. 1 (A) is a cross-sectional view showing a state where a pack body is inserted into a recess of a lower die, FIG. 1B is a cross-sectional view at the time of the heating process, and FIG. 1C is a cross-sectional view at the time of completion of the heating process.
FIG. 2 is a perspective view showing a state in which cotton is stuffed into a bag.
FIG. 3 is a partially omitted perspective view showing a cotton block body for cutting out a predetermined amount of cotton.
FIG. 4 is a cross-sectional view similar to FIG. 1 (B) showing another embodiment of the molding method of the present invention.
FIG. 5 is a cross-sectional view similar to FIG. 1 (B) showing still another embodiment of the molding method of the present invention.
FIG. 6 is a cross-sectional view similar to FIG. 1B, showing another embodiment of the molding method of the present invention.
FIG. 7 is a cross-sectional view showing an example of a state where a lower mold recess is filled with cotton based on a conventional molding method.
FIG. 8 is a cross-sectional view showing a state in which a lower mold and an upper mold are closed based on a conventional molding method.
FIG. 9 is a cross-sectional view showing another example of a state in which the concave portion of the lower mold is filled with cotton based on a conventional molding method.
[Explanation of symbols]
A Mold W Cotton 10 Lower mold 10a Recess 10b Small recess 10c Small recess 20 Upper mold 20a Protrusion 30 Cavity 40 Bag 50 Pack body 50A Pack body 50B Pack body 50C Pack body 50D Pack body 50E Pack body 50F Pack body

Claims (6)

In a method of forming a cushion material by filling cotton into a cavity formed between a pair of molds, heating the cotton to melt a part thereof, and then cooling and solidifying the cotton, the cotton is put into the cavity. Cushion characterized in that instead of direct filling, the cotton is packed in a bag made of a resin having a lower melting temperature, vacuumed and sealed to form a pack body, and the pack body is inserted into the cavity. Material forming method. The method for molding a cushion material according to claim 1, wherein the pack body is inserted so that the filling amount of cotton in the cavity is different in each part of the cavity. 3. The method according to claim 2, wherein a plurality of the pack bodies are used, and a different number of pack bodies are arranged in each portion in the cavity, whereby the filling amount of cotton in the cavity is made different in each portion of the cavity. The method for forming the cushioning material according to claim. A plurality of pack bodies having different filling capacities of the cotton are used, and each pack body is arranged in each part of the cavity, whereby the amount of filling of the cotton in the cavity is made different in each part of the cavity. A method for molding a cushion material according to claim 2. The at least one pack body among the plurality of pack bodies is stuffed with cotton having higher hardness than cotton stuffed in other pack bodies. Molding method of cushion material. The method for molding a cushion material according to any one of claims 1 to 5, wherein a plurality of the pack bodies are used, and at least one pack body of the plurality of pack bodies is formed smaller than the other pack bodies. .

Images