JPH048075B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of manufacturing a cushion body such as a headrest provided in a vehicle seat.

[Prior Art] FIG. 10 shows a conventional headrest of an automobile.

The headrest 1' includes a pillow-shaped cushion part 2' and a stay 3' that protrudes from the cushion part 2'.
have. The cushion portion 2' is composed of a foam 4' fixed to the head of the stay 3', and a resin cover 5' covering the foam 4'.
Both ends of the stay 3' are inserted into a seat 100 such as a driver's seat of an automobile, and supported so as to be able to rise and fall.

The above-mentioned conventional headrest 1' is generally manufactured by the following various methods.

The first method is to manufacture the cover 5' by sewing (hereinafter abbreviated as the sewing method). 9th
The figure is an explanatory diagram for assembling the headrest 1' using this sewing method. In the sewing method, the stay 3' is first inserted and set in a mold (not shown), and a foamable resin is injected into the mold and foamed to form the stay 3' as shown in FIG. A foam body 4' is formed. Separately, a resin sheet (not shown) is cut and sewn to produce a bag-shaped cover 5' having an opening 5a' as shown in FIG. 9.
After inserting the foam 4' into the cover 5' through the opening 5a', the opening 5a' is sewn to integrate the stay 3', the foam 4', and the cover 5'. Note that another method for sealing the opening 5a' may be to use a fastener or the like that is attached to the opening 5a' in advance.

The second method is to manufacture the cover 5' by blow molding (hereinafter referred to as blow molding method).
It is. In this method, a parison made of thermoplastic resin is sandwiched between molds, air is blown into the inside of the parison to inflate it, and the parison is cooled and solidified to form the cover 5'. Furthermore, the stay 3' is inserted and set into the cover 5' in the mold, and a foamable resin is injected and foamed to form a foam 4', and the stay 3', the foam 4', and the cover 5 are injected and foamed. ′ to be integrated.

The third method is to manufacture the cover 5' by slush molding (hereinafter abbreviated as slush molding method). In this method, plastisol is deposited inside a mold, melted and gelled, and then cooled and solidified.
A cover 5' is formed. After this, the foam 4' is placed inside the cover 4 by a method similar to the blow molding method described above.
The stay 3', the foam body 4', and the cover 5' are integrated.

[Problems to be Solved by the Invention] Incidentally, in recent years, there has been an increasing trend toward higher quality products in all kinds of products. The interior parts of automobiles, such as the headrest mentioned above, are no exception, and the main part of the cover is made of fabric such as tricot made of synthetic fibers or natural fibers, aiming at a higher quality visually and tactilely. It is being considered. That is, the cover is composed of a front cover made of fabric and a rear cover made of resin sheet,
The cavity surrounded by the front cover and rear cover is filled with foam.

When attempting to manufacture this type of headrest using the conventional methods described above, the following problems arose.

That is, blow molding and slush molding cannot be used. As a premise that these methods can be used, the cover material must be resin. Also, even if it is made of resin, fabric cannot be used. Furthermore, multiple resins are used in the process of making one cover, and it is not possible to use each resin partially.

Therefore, there is no choice but to use a sewing method that is applicable to materials other than resin and fabric, and also allows combinations of different materials. However, there is a problem in that sewing the cover 5' takes a lot of time and effort. Furthermore, the manufacturing process for the cover 5' and the manufacturing process for the foam body 4' must be combined into separate processes.
Furthermore, a subsequent assembly and integration process is also required, which has the disadvantage of complicating the manufacturing process. In addition,
Since seams were visible on the cover 5' of the completed headrest 1', there was a problem that the product looked unsightly. Incidentally, the seam has also been covered with a beaded edge, but this increases the number of manufacturing steps and also makes the product look unsatisfactory.

[Means for Solving the Problems] The present invention has been made to solve the above problems, and its gist is that a hollow portion surrounded by a first cover and a second cover is filled with a foam. In this method of manufacturing a cushion body, a pair of molds are prepared in advance, and at least one of the first cover and the second cover is provided with a protrusion extending into the cavity, and the protrusion is provided with a locking member for the foam. A first cover and a second cover are set in each of the molds and the molds are clamped, and a foaming resin is injected into the cavity formed when the molds are clamped to form a foam. The method of manufacturing a cushion body is characterized in that the first cover and the second cover are joined to each other via the foamed body.

[Operation] In the process of foaming the foamable resin to form a foam, the foam and the first cover adhere to each other due to the adhesive properties of the foam, and the foam and the second cover also adhere to each other. As a result, the first cover and the second cover are joined via the foam. In particular, in the case of a cover provided with a protrusion, the cover and the foam are bonded extremely firmly by the foam entering or wrapping around the locking part of the protrusion. Ru.

Further, at the same time as the foam is formed, the first cover, the second cover, and the foam are integrated.

Furthermore, since the first cover and the second cover are joined via the foam, both covers can be made of different materials. Further, either the first cover or the second cover can be made of fabric or made of a material other than resin.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings from FIG. 1 to FIG. 6. Incidentally, this embodiment is an embodiment in which a headrest for an automobile is manufactured as a cushion body.

First, the headrest 1 manufactured by this method will be briefly explained based on FIG. 6.

Headrest 1 is the driver's seat or passenger seat 1 of a car
00, with a through hole 2a in the center.
It has a donut-shaped cushion part 2 having a shape of a doughnut, and a stay 3 protruding from the cushion part 2.
The cushion part 2 is surrounded by a front cover (first cover) 6 facing the front side of the vehicle, a rear cover (second cover) 7 facing the rear side of the vehicle, and the front cover 6 and the rear cover 7. The foam is filled in the cavity formed by the foam (neither the cavity nor the foam is shown in FIG. 6).

The headrest 1 is manufactured by the following procedure.

First, as shown in FIG. 1, the front cover 6 is set on the female mold 11, the stay 3 is set inside it, and the rear cover 7 is set on the male mold 12. This will be explained in detail below.

The front cover 6 as a material is made of tricot 6a (fabric) made of polyester fiber,
It is composed of a resin film 6b attached to the back surface of a tricot 6a. The resin film 6b is made of vinyl chloride resin and acrylonitrile.
It is made of polymerized resin with butadiene styrene resin (ABS resin).

Further, the female mold 11 is composed of a lower mold 11A, an upper mold 11B, and an insert 11C, and has a doughnut-shaped molding recess 11a. In addition, the lower mold 11A
The dividing surface between the upper mold 11B and the insert 11C is located at the largest expansion part of the molding recess 11a. The molded recess 11a has a constricted part 1 that gradually shrinks at the upper part.
1b, and a tapered portion 11c that is located above the constricted portion 11b and gradually expands.

In this embodiment, the laminate of the tricot 6a and the film 6b is vacuum formed and deep drawn using a female mold 11, and the front cover 6 is formed into a female mold by closely contacting the surface of the molding recess 11a. Set to 11.

Next, the stay 3 is placed inside the front cover 6 set in the female mold 11 as described above. As shown in FIG. 5, the stay 3 is formed by bending a round bar into a substantially U-shape in advance. When setting the stay 3 in the female mold 11, insert both ends of the stay 3 into the through holes previously formed in the tricot 6a and film 6b during the vacuum forming process.
1 from the inside to the outside.

On the other hand, the rear cover 7 is made of a flexible polyvinyl chloride resin and has been formed in advance by injection molding. The rear cover 7 is the fourth
As shown in the figure, a back plate 7b has an opening 7a formed in the center, and ribs (protrusions) 7 that stand up from the inner surface of the outer and inner edges of the back plate 7b, respectively.
c, 7d. A plurality of holes (locking portions) 7e and 7f are formed in each of the ribs 7c and 7d.
Further, in the back plate 7b, overlap portions 7g and 7h are formed outside the rib 7c at the outer edge and inside the rib 7d at the inner edge, respectively, to cover the edge of the front cover 6.

The rear cover 7 is set on the male die 12 by vacuum suction. At that time, each of the overlap portions 7g and 7h is set so as to be flipped outward against the elasticity of the material of the rear cover 7.

Next, the positioning pin 11e provided in the upper mold 11C of the female mold 11 is inserted into the pin hole 1 provided in the male mold 12.
2a, and the female mold 11 with the front cover 6 and stay 3 set thereon and the male mold 12 with the rear cover 7 set thereon are clamped as shown in FIG.
Then, each overlap portion 7 of the rear cover 7
g and 7h are the tapered parts 11 of the female mold 11, respectively.
It comes into contact with the film 6b of the front cover 6 set at point c. As a result, a cavity 8 is formed surrounded by the front cover 6 and the rear cover 7.

Then, while maintaining the above mold clamping state, a foamable urethane resin is injected into the cavity 8 through a gate (not shown) and foamed, thereby forming a foamed body 4 made of urethane foam.

During the formation process, the foam 4 adheres to the film 6 of the front cover 6 due to its own adhesive properties.
b, and also to the inside of the rear cover 7. As a result, the front cover 6 and the rear cover 7
are joined via the foam 4.

In particular, in the rear cover 7, the urethane foam also enters into the many holes 7e, 7f of the ribs 7c, 7d during the formation process.
Due to the urethane foam in f, each rib 7c, 7
The urethane foams located on both sides of d are integrally connected. As a result, the rear cover 7 and the foam body 4 are engaged with each other not only by the above-mentioned adhesive means but also through the holes 7e and 7f.
Since it will be firmly joined, the rear cover 7
does not separate from the foam 4.

Further, in this embodiment, the upper opening 6c (shown in FIG. 1) of the front cover 6 is formed by being narrowed by the narrowing part 11b of the female mold 11, and after the foam 4 is formed, Since the shape-retaining foam 4 is housed inside the front cover 6, the foam 4 will not peel off from the front cover 6 and fly out.

Incidentally, the stay 3 is fixed by a foam body 4 surrounding the stay 3.

In this way, the front cover 6, the rear cover 7, and the foam 4 are integrated at the same time as the foam 4 is formed.

Next, open the female mold 11 and male mold 12, and insert the insert 1.
The front cover 6 placed on the flat part 11d of 1C is cut and removed. Further, the lower mold 11A is separated from the upper mold 11B and the insert 11C, and the unfinished headrest 1 is separated from the lower mold 11A. Then, the head rest 1 is removed from the upper mold 11B and the insert 11C, and the tricot 6a and film 6b that were arranged along the tapered part 11c of the female mold 11 are cut out (trimmed). Then, the respective overlap portions 7g and 7h of the rear cover 7, which had been flipped up to the outside against the elasticity, are restored to their original shapes. As a result, as shown in FIG.
g and 7h cover the edge of the opening 6c of the front cover 6 from the outside and are in close contact with each other.

In this way, the headrest 1 as shown in FIG. 6 is completed.

In this embodiment, the foamable urethane resin is injected into the cavity 8 from the gate after mold clamping and is foamed, but as another method, it is possible to
The foamable urethane resin may be injected into the front cover 6 from the opening 6c, and then the mold may be clamped to cause foaming within the cavity 8.

Since this headrest 1 has a through hole 2a provided in the center of the cushion portion 2, it does not give any pressure to the occupant in the rear seat. especially,
When the front passenger seat is vacant, the passenger in the rear seat can look out ahead of the vehicle through the through hole 2a, and is extremely comfortable.

Further, since the front cover 6 of the cushion part 2 has the tricot 6a on its surface, it gives the headrest 1 a high-class feel both visually and tactilely.

Furthermore, there is no seam in the tricot 6a of the front cover 6, and the opening 6 of the front cover 6 is
The edge c is the overlap part 7 of the rear cover 7.
Since the overlapping portions 7g and 7h are covered and hidden by the overlapping portions 7g and 7h and are in close contact with the edge of the opening 6c of the front cover 6 due to the elasticity of the soft resin, the headrest 1 has an extremely high design quality.

7 and 8 respectively show the rear cover 7.
This figure shows another example of the protrusion and the locking part provided in the figure.

In the embodiment shown in FIG.
A rib 71 having an inverted L-shaped cross section stands up as a protrusion from the back plate 7b. The rib 71 includes a standing portion 71a that integrally extends from the back plate 7b, and a standing portion 71a that extends integrally from the back plate 7b.
The locking portion 71b is bent at a right angle at the tip of the locking portion 71b. Using this rear cover 7,
When the headrest 1 is manufactured in the same manner as in the first embodiment, when the foamable urethane resin is injected into the cavity 8 and fired, the urethane foam also enters the back side of the locking portion 71b of the rear cover 7. , rib 7
A foam 4 is formed so as to surround the foam 1. As a result, similarly to the first embodiment, the rear cover 7 and the foam 4 are locked to each other, and the rear cover 7 is attached to the foam 4.
There will be no departure from.

In the embodiment shown in FIG.
Mushroom-shaped protrusions 72 are scattered in an upright manner from the back plate 7b. The protrusion 72 includes a substantially conical leg 72a that integrally extends from the back plate 7b, and a leg 72a that extends integrally from the back plate 7b.
Umbrella-shaped head (locking part) 72 formed at the tip of a
It is composed of b. When the headrest 1 is manufactured using this rear cover 7 in the same manner as in the first embodiment, when foamable urethane resin is injected into the cavity 8 and foamed, the urethane foam forms the projections 72.
The foam 4 is formed so as to enclose the . The head 72b is the locking portion 7 in the second embodiment.
It has the same effect as 1b.

This invention is not limited to the above-mentioned embodiments, and various embodiments are possible.

For example, both of the pair of molds may be female molds.

Further, both the first cover and the second cover may be made of the same type of resin, or either the first cover or the second cover may be made of a fabric made of natural fibers.

Furthermore, both the first cover and the second cover may be provided with projections and locking portions, and the foam and each cover may be firmly joined via these projections and locking portions.

In addition, in each of the above embodiments, the first cover is molded and set in the mold at the same time by vacuum forming using a mold (female mold), but it is not necessary to mold it in advance by other methods. The first cover may be set by attaching it to a mold used in general foam molding.

Further, the cushion body is not limited to the headrest of an automobile, but may also be an interior part of the vehicle such as an armrest or a seat backrest, and can be applied to items other than automobiles.

[Effects of the Invention] As explained above, according to the present invention, the first cover, the second cover, and the foam can be integrated at the same time as forming the foam. Therefore,
The manufacturing process of the cushion body can be simplified compared to conventional sewing methods.

In addition, the bonding state between the cover provided with the protrusion and the foam body is such that the foam formed in the cavity enters into the locking part or wraps around the locking part, so the cover and the foam body are extremely difficult to bond together. Can be firmly joined.

Furthermore, since the first cover and the second cover are joined via the foam, it is possible to manufacture a cushion body in which both covers are made of different materials.
Moreover, it is also possible to manufacture a cushion body having a cover other than resin. Therefore, the cushion body can be manufactured by this manufacturing method regardless of the material of the cover.

[Brief explanation of drawings]

The drawings from Fig. 1 to Fig. 6 show one embodiment of the present invention, Fig. 1 is a sectional view showing the state before the mold is clamped, and Fig. 2 is a sectional view showing the state before the mold is clamped. Fig. 3 is a sectional view of the headrest as a completed cushion body;
FIG. 5 is a perspective view of the rear cover as the second cover, FIG. 5 is a perspective view of the stay, and FIG. 6 is a perspective view of the headrest. Furthermore, FIGS. 7 and 8 are perspective views showing other embodiments of the protrusion and the locking portion, respectively. Further, FIG. 9 is an assembled perspective view of a conventional head rest manufacturing method, and FIG. 10 is a perspective view of the same head rest. 1...Cushion body (headrest), 4...
Foam, 6... First cover (front cover), 7...
...Second cover (rear cover), 7c, 7d...Protrusion (rib), 7e, 7f...Locking part (hole), 8...
...Cavity part, 11, 12...Mold, 71...Protrusion (rib), 72...Protrusion, 71b...Locking part, 7
2b...Locking part (head).

Claims (1)

[Claims] 1. In a method for manufacturing a cushion body in which a cavity surrounded by a first cover and a second cover is filled with a foam, a pair of molds is prepared in advance, and at least one of the first cover and the second cover is filled with a foam. A protrusion is provided extending into the cavity, and a locking portion for the foam is formed on the protrusion, and a first cover and a second cover are respectively set on each of the molds and the molds are clamped. Then, a foamable resin is injected and foamed into the cavity formed when the mold is clamped to form a foam, and the first cover and the second cover are joined through this foam. The manufacturing method of the characteristic cushion body.