JPH0592087A - Manufacturing method of automobile head dress - Google Patents

Abstract

(57) [Abstract] [Purpose] In manufacturing a headrest for an automobile using a foamable synthetic resin, at the time of foaming, the synthetic resin is prevented from entering the core material of the headrest. [Structure] A core member 2 in which a headrest rotating mechanism is provided.
In a method of manufacturing a headrest in which a foamable synthetic resin is injected into the mold 5 from an injection nozzle 52a, the thermoplastic resin 7 is placed in the hole 25 formed on the outer surface of the core material 2. The foamable synthetic resin is injected and molded in a state where the hole 25 is filled and the hole 25 is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an automobile headrest by injecting a foamable synthetic resin into a mold.

[0002]

2. Description of the Related Art A headrest for an automobile is mounted to rest the head of a person sitting on a seat of the automobile, and sometimes to protect the head from an impact. Made from a material that is both elastic and structurally strong.

Rubber has been widely used for a long time as a material which meets such a purpose, but due to the development of synthetic chemistry in recent years,
Foaming synthetic resins such as urethane foam are often used. The foamable synthetic resin has a property of solidifying while foaming. The foamed and hardened synthetic resin is excellent as a cushioning material because it has elasticity because it has a large number of minute bubbles inside and also has good shape retention. In addition, since it is easy to handle during manufacturing, it is optimal as a manufacturing raw material for products such as seats and headrests that require cushioning properties.

By the way, such a headrest is detachably provided on the top portion of a seat back S of an automobile as shown in FIG. 6, and has a core member 2 in the center, a cushion member 3 around the core member 2, and a headrest 1. And a pole 4 for fitting the seat back S to the seat back S. The inside of the core material 2 is hollow, and a rotating mechanism 20 for changing the angle of the headrest 1 mounted in the hollow is often provided. For example, the rotating mechanism 20 includes a bracket 21 provided on an upper portion of the pair of poles 4 and a rotating shaft 22 attached to the bracket 21.
The rotary plate 23 is rotatably supported by the rotary plate 23, and the rotary plate 23 is generally integrally fixed to the core 2. With this configuration, the rotating plate 2
Since 3 is rotatable about the rotating shaft 22, the core member 2 integrally fixed to the rotating plate 23, and by extension, the core member 2.
The headrest 1 in which is installed can freely change the angle in the front and rear direction while being attached to the seat back S.

In such a headrest 1, as shown in FIGS. 3 to 5, a core material 2 is incorporated in a mold 5 composed of an upper mold 51 and a lower mold 52, and an injection nozzle 52a of FIG. It is generally manufactured by injecting resin and foaming it inside the mold 5.

By the way, when the core material 2 is mounted inside the mold 5 as described above, the rotating mechanism 2 is provided in the hollow portion of the core material 2.
0 is installed internally, and the pole 4 is then used as the core material 2
Also, since it penetrates through the mold 5 and protrudes to the outside, and the surface of the core 2 has a long hole 24 for securing the rotation amount of the headrest 1, the inside of the mold 5 is When the synthetic resin is foamed, the synthetic resin foamed from the elongated hole 24 may enter the core material 2 and adhere to the rotating mechanism 20 to hinder the smooth rotation of the core material 2.

Therefore, in order to avoid the above-mentioned inconvenience, the packing material 6 is held between the surface of the core material 2 on which the elongated hole 24 is formed and the inner surface of the mold 5. By doing so, it is possible to prevent the resin from entering through the elongated hole 24.

[0008]

However, in the case where the holed surface of the core material 2 and the inner surface of the mold 5 come into contact with each other as described above, the packing material 6 is inserted between them. By doing so, it is possible to prevent the resin from entering the inside of the core material 2, but if there is a hole in the portion where the above-mentioned contact is not made, the packing material 6 cannot be held, so that it is effective. It is difficult to close the hole. Conventionally, it was done to attach an adhesive tape and close the hole, but when the part with the hole is on the same surface,
It is difficult to attach the adhesive tape effectively, such as when it is a hole drilled in the uneven part, it takes time and time, and it becomes a neck in the headrest manufacturing using the foamable synthetic resin. It was

The present invention has been made in order to solve the above-mentioned conventional inconveniences, and it is dealt with by inserting the packing material 6 in the manufacture of a headrest for an automobile using a foamable synthetic resin. It is an object of the present invention to provide a manufacturing method capable of effectively preventing intrusion of synthetic resin into the inside of the core material 2 of the headrest 1 which cannot be performed.

[0010]

According to a method of manufacturing a headrest for an automobile of the present invention, a core material in which a rotating mechanism of the headrest is installed is internally provided in a mold, and then a foamable synthetic resin is provided in the mold. In the method of manufacturing a headrest that is injected into
The hole is closed by filling the hole formed on the outer surface of the core material with a thermoplastic resin, and in that state, the foamable synthetic resin is injected into the mold for molding.

[0011]

According to the method of manufacturing a headrest for an automobile of the present invention, since the thermoplastic resin is used to fill the holes formed on the outer surface of the core material of the headrest, the thermoplastic resin is heated to soften it. It can be freely deformed to completely close the hole. Therefore, when the foamable synthetic resin is injected into the mold and foamed when the headrest is manufactured, the foamed resin does not enter the inside of the core material.

[0012]

EXAMPLE As shown in FIG. 6, a headrest 1 according to the present invention comprises a core material 2 and a cushion material 3 formed on the outer periphery thereof.
And a pole 4 protruding from the inside of the core material 2 to the outside. Then, as shown in FIGS. 3 to 5, the manufacturing is performed by injecting a foamable synthetic resin into a mold 5 containing a core material 2 therein.

The case of using the mold 5 illustrated in FIG. 3 will be described below. The mold 5 is composed of a flat plate-shaped upper mold 51 for locking the core material 2 on the lower surface and a box-shaped lower mold 52 whose inner surface is processed to form the outer shape of the headrest 1. The foamable synthetic resin is supplied into the mold 5 from an injection nozzle 52a provided on the side of the lower mold 52.

The expandable synthetic resin used in the present invention is a synthetic resin which cures while foaming when heated. Examples of such expandable synthetic resin include polystyrene and polyurethane.

The outer frame of the core 2 is composed of a metallic lid 2a and a synthetic resin box 2b closed by the lid 2a. Reference numeral 2c is a C-shaped bone body in which both ends are vertically welded to the outer surface of the lid body 2a, and plays a role of enhancing the reinforcing effect of the entire headrest 1. The inside of the box body 2b is hollow, and the turning mechanism 20 of the headrest 1 is installed in this hollow as shown in FIG. The rotating mechanism 20 includes a pair of rotating plates 2 provided upright on the inner surface of the lid 2a.
3 and a pair of brackets 21 fixed to the upper ends of the poles 4
Since they are rotatably supported by the rotation shaft 22, the rotation plate 23 is attached to the bracket 21.
It is possible to rotate around the rotation axis 22 with respect to. In addition, the upper end of the pole 4 in FIG. 6 is adapted to be recessed into the box body 2b through a long hole 24 formed in the bottom portion of the box body 2b.

The core material 2 constructed as described above is mounted on the upper mold 51 through the packing material 6 shown in FIG. 1 or 3. For this mounting, first, the pole 4 is passed through a pair of fitting insertion holes 61 arranged in parallel along the longitudinal centerline of the packing material 6, and then the upper mold 5 punched corresponding to the fitting insertion holes 61.
The pole 4 is inserted into the first insertion hole 51a. Then, the upper mold 51 and the box body 2b are pressed against each other via the packing material 6.
Further, the locking of the core material 2 to the upper mold 51 is performed by screwing a locking piece 51b fitted to the pole 4 protruding to the outside as shown in FIG. 1 or FIG.

By interposing the packing material 6 between the box body 2b and the upper mold 51 as described above, the hole opened on the surface of the box body 2b can be closed, but the surface of the box body 2b is closed. Since the packing material 6 cannot intervene in the hole opened in the portion which does not come into contact with the inner surface of the mold 5, it has been conventionally closed by attaching an adhesive tape.

For example, as shown in FIG. 6, a pair of working holes 25 necessary for processing are provided on the surface of the lid 2a. Then, a strip-shaped flat plate 2d is welded over them, and a skeleton 2c is further welded thereto, but both ends of the working hole 25 are left open. If such a portion is to be closed by sticking an adhesive tape, it is necessary to stick it over two flat surfaces having a step between the surface of the lid body 2a and the surface of the flat plate 2d, which is troublesome. It took manpower and time, and it was difficult to completely close it.

FIG. 2 is a sectional view taken along the line AA in FIG. 1, in which the upper stage is a state immediately after the working hole 25 is filled with the thermoplastic resin 7, and the lower stage is the thermoplastic resin 7 injected into the mold 5, Shows the state of being heated and foamed. That is, in the present invention, as shown in the upper part of FIG. 1 or FIG. 2, instead of attaching the adhesive tape to the working hole 25, the thermoplastic resin 7 is filled therein and closed.

The thermoplastic resin 7 softens and exhibits plasticity without reaction when heated, and solidifies when cooled. Further, it is a resin whose plasticity is reversibly maintained even after repeated cooling and heating.

Examples of such resins include polypropylene, polyvinyl chloride, polystyrene, polyvinylidene chloride, fluororesin, polymethylmethacrylate, etc. as the addition polymerization type, and as the polycondensation type one. , Polyamide, polyester, polycarbonate, polyphenylene oxide, and the like, polyaddition type includes plastic polyurethane, and ring-opening polymerization type includes polyacetal. Usually, these thermoplastic resins are commercially available in the form of granules or powders, but in order to carry out the method of the present invention, it is preferable to use those which are preformed into a rod shape.

In order to close the opening, the rod-shaped thermoplastic resin 7 is heated by a heating tool in the same manner as so-called metal brazing, and is pressed around the working hole 25. Then, the thermoplastic resin 7 softens and assumes a fluidized state, so that the edge of the surrounding lid 2a and the flat plate 2d are irrespective of the shape and state of the opening as shown in the upper part of FIG.
The work hole 25 can be easily closed by adhering to the edge of the work hole 25.

When the closing of the working hole 25 by the thermoplastic resin is completed, the upper die 51 is put on the lower die 52 with the core material 2 downward as shown in FIG. 1 or 2, and the four corners of the upper edge of the lower die 52 are covered. The upper mold 51 provided corresponding to the male screw 52b that is erected
The fitting hole 51d is fitted and the nut 52c is screwed to fasten the upper mold 51 to the lower mold 52. In this state, the mounting of the core material 2 in the mold 5 is completed.

Then, a predetermined amount of a predetermined starting material of a predetermined expandable synthetic resin is injected from the injection nozzle 52a into the mold 5, and the mold 5 is heated to a predetermined temperature. Then, the above-mentioned starting material undergoes a polymerization reaction while generating gas by this heating to form a porous cushioning material 3 (indicated by the dotted lines in the lower part of FIG. 2), and as shown in FIG. It is possible to obtain the headrest 1 in which 2 is included. The thermoplastic resin 7 with the work holes 25 closed is heated in the step of heating the foamable synthetic resin injected into the mold 5 to foam the same.
As shown in the lower part of FIG. 2, the resin is softened and integrated with the foamed synthetic resin. Therefore, invasion of the foamable synthetic resin from the working hole 25 into the core material 2 can be effectively prevented.

FIG. 4 is a partially cutaway perspective view showing another example of the die 5, and FIG. 5 is a sectional view taken along the line AA. In the case of this mold 5, the upper mold 51 and the lower mold 52 are hinged 5 on one side.
It is rotatably connected by 3. On the other side,
A pair of left and right pressing clamps 55 (only one is shown) for pressing the upper mold 51 with the lower mold 52 closed, and a locking clamp 54 for locking the coupled upper mold 51 and lower mold 52 are provided. There is.

The pressing clamp 55 comprises an S-shaped pressing tool 55b which is rotatably supported by a shaft 55d on a bracket 55c provided on the side of the lower mold 52. The S-shaped pressing tool 55b is provided with a pressing piece 55a at its upper end and a handle 55f at the other end, and is urged clockwise by an urging means 55e such as a spring.

The locking clamp 54 includes a bracket 54c provided on the side surface of the lower mold 52, and a connecting piece 54g rotatably supported by the bracket 54c around a shaft 54d.
The connecting piece 54g includes an S-shaped locking tool 54b that is pivotally supported about a shaft 54e. And
The top end of the locking tool 54b is provided with a top cap 54 having a top shape so as to correspond to a resin supply hole 54f formed on the upper mold 51.
a is provided. The other structures of the mold 5 are the same as those described above except that the injection nozzle 52a is not attached to the lower mold 52 and that the upper mold 51 is provided with a resin supply hole 54f described later. Exactly the same.

Since the mold 5 is constructed as described above, the core material 2 is mounted on the upper mold 51 after the upper mold 51 is flipped up around the hinge 53. When the mounting of the core material 2 is completed, the upper die 51 is rotated around the hinge 53 to move the lower die 5
2 and then operate the handle 55f of the pressing clamp 55 to move S
The character-shaped pressing tool 55b is rotated clockwise about the shaft 55d, and the upper die 51 is pressed by the pressing piece 55a. In this case, since the S-shaped pressing tool 55b is urged in the clockwise direction by the urging means 55e, the pressing force against the upper die 51 is maintained even if the urging force releases the hand from the handle 55f.

In this state, the foamable synthetic resin is supplied into the mold 5 from the nozzle (not shown) through the resin supply hole 54f.

After the supply of the resin into the mold 5 is completed, the locking tool 54b of the locking clamp 54 is rotated in the clockwise direction about the shaft 54e, and the closing plug 54a at the tip of the locking tool 54b is moved to the resin supply hole 54f. To fit. In that state, connect the connecting piece 54g to the shaft 5.
When it is rotated counterclockwise about 4d, the stopper 5
The locking clamp 54 locks the upper mold 51 and the lower mold 52 of the mold 5 when the locking clamp 54 is pressed downward while the 4a is fitted in the resin supply hole 54f.

To open the upper mold 51 in the mold 5 after the headrest 1 is formed, the above operation may be reversed.

By using this mold 5, the upper mold 51 can be easily attached to and detached from the lower mold 52, which is convenient for rationalizing the work.

[0033]

As described above, according to the method of manufacturing an automobile headrest of the present invention, the hole formed on the outer surface of the core material of the headrest is filled with a thermoplastic resin to close the hole, and then the foaming property is improved. Since it is manufactured by injecting a synthetic resin into a mold in which a core material is incorporated, it is possible to perform a complete closure regardless of the shape and the site, as compared with the conventional closure of holes by sticking an adhesive tape. Therefore, the invasion of the expandable synthetic resin into the core material can be completely blocked, so that the product defect due to the invasion of the expandable synthetic resin into the core material can be completely eliminated.

Further, since the thermoplastic resin is softened by heating and exhibits extremely high fluidity, the work of closing the holes is easy, and the number of manufacturing steps can be greatly reduced as compared with the conventional method.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a mold used for carrying out the method of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partially cutaway sectional view showing an example of a mold used for carrying out the method of the present invention.

FIG. 4 is a partially cutaway perspective view showing another example of a mold for carrying out the present invention.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a perspective view showing a state in which a headrest is mounted on a seat back.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Headrest 2 Core material 2a Lid body 2b Box body 2c Bone body 3 Cushion material 4 Pole 5 Mold 51 Upper mold 51a Fitting insertion hole 51b Locking piece 52 Lower mold 52a Injection nozzle 52b Male screw 6 Packing material 7 Thermoplastic resin

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kihachiro Takemura 1-14 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Delta Industrial Co., Ltd.

Claims (1)

[Claims] 1. A method of manufacturing a headrest in which a core material having a headrest rotating mechanism is internally provided in a mold, and then a foamable synthetic resin is injected into the mold, wherein the outer surface of the core material is provided. A method of manufacturing an automobile headrest, characterized in that the formed hole is closed by filling the hole with a thermoplastic resin, and in that state, a foamable synthetic resin is injected into a mold for molding.