JPH01153183A - Production of cushion body - Google Patents

Abstract

PURPOSE: To strongly join a cover and a foamed body and to integrate first and second covers with the foamed body by providing a projection body extended to a void part on one of the first and second covers and forming a locking part to the foamed body at the projection body. CONSTITUTION: A front surface cover 6 is set to a female mold 11, a stay 3 is set to the inside and a rear side surface cover 7 is set to a male mold 12. The rear side surface cover 7 is provided with a back plate 7b where an opening 7a is formed at the center and ribs (projection bodies) 7c and 7d respectively erected from the inner surface at the outer edge part and inner edge part of the back plate 7b. At the respective ribs 7c and 7d, plural holes (locking parts) 7e and 7f are formed. Then, the female mold 11 and the male mold 12 are clamped. Then, foamable urethane resin is injected to a void part 8 and foamed. Urethane foam intrudes into many holes 7e and 7f of the ribs 7c and 7d as well in the formation process and the urethane foam positioned on both sides with the respective ribs 7c and 7d as boundaries is integrally connected. As a result, the rear side surface cover 7 and the foamed body 4 are locked to each other through the respective holes 7d and 7f and strongly joined.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a method for manufacturing a cushion body such as a headrest provided in a vehicle seat.

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

The headrest 1' includes a pillow-shaped cushion part 2',
It has a stay 3' that protrudes from the cushion part 2'. 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'. Then, both ends of the stay 3' are inserted into a seat 100 such as a driver's seat of a car,
It is supported so that it can be raised and lowered.

The above 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). FIG. 9 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 foamable resin is injected into the mold and foamed to form the stay 3' as shown in Fig. 9. 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 attached to the opening 5a' in advance.

The second method is to manufacture the cover 5' by blow molding (hereinafter abbreviated as blow molding method). In this method, a parison made of thermoplastic resin is sandwiched between molds,
Air is blown into 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 foaming resin is injected and foamed to form a foam 4', and the stay 3', the foam 4', and the cover 5 are
′ and visualize it.

The third method is to manufacture the cover 5' by slush molding (hereinafter abbreviated as slush molding method). In this method, plastisol is deposited in a mold, melted and gelled, and solidified by cooling to form the cover 5'. Thereafter, a foam 4' is formed inside the cover 4 by a method similar to the blow molding method described above, and the stay 3', the foam 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 headrests mentioned above, are no exception, and the main part of the cover is made of 77 bricks of tricot made of synthetic fibers or natural fibers, giving a visual and tactile sense of luxury. things are being considered. That is, the cover is composed of a front cover made of 77 brick 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, 7-abric 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 77 brick, and also allows combinations of different materials. However, there is an inconvenience in that sewing the cover 5' is extremely time consuming. Also, cover 5'
The manufacturing process of the foam body 4' and the manufacturing process of the foam body 4' must be separate processes, and a subsequent assembly and integration process is also required, which has the drawback of complicating the manufacturing process. In addition, seams are visible on the cover 5' of the completed headrest 1', resulting in a problem of poor appearance as a product. Incidentally, the seams have also been covered with beaded edges, but this increases the number of manufacturing steps and also does not give the product a poor appearance.

[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 the method for manufacturing a cushion body, a pair of molds is prepared in advance, a protrusion extending to the cavity is provided on at least one of the first cover and the second cover, and the protrusion has a locking member for the foam. Then, the first cover and the 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 a foam is formed through the foam, and a first cover and a second cover are joined to each other via the foam.

[Operation 1] 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.

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 force bars can be made of different materials. Further, either the first cover or the second cover can be made of 77 brick or made of a material other than resin.

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

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

The headrest 1 is provided in a driver's seat or a passenger seat 100 of an automobile, and has a donut-shaped cushion part 2 having a through hole 2a in the center, and a stay 3 protruding from the rear part 2. The cushion portion 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. It is composed of a foam (both the cavity and the foam are not shown in FIG. 6) filled in the cavity to be formed.

The headrest 1 is manufactured by the following procedure.

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

The front cover 6 as a material is made of tricot 6a (7abric) and tricot) 6a made of polyester fiber.
A resin film 6b is attached to the back surface of the holder. The resin film 6b is made of vinyl chloride resin and 7-crylonitrile butadiene styrene resin (A B
It is formed from a polymerized resin with S resin).

Further, the female mold 11 includes a lower mold 11A, an upper mold 11B, and an insert 1.
1C, and has four doughnut-shaped parts 11a.
have. Note that the dividing surface between the lower mold 11A, 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 11b that gradually shrinks at the upper part, and a tapered part 11c that is located above the constricted part 11b and gradually expands.

In this embodiment, the front cover 6 is made into a female by vacuum forming and deep drawing a laminated product of the above-mentioned tricot 6a and film 6b using a female mold 11, and bringing it into close contact with the surface of the molded recess 11a. Set in mold 11.

Next, the stay 3 is placed inside the front cover 6 set in the female die 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 from the inside of the female mold 11 to the outside into the through holes previously formed in the tray 6a and film 6b during the vacuum forming. Insert.

On the other hand, the rear cover 7 is made of flexible polyvinyl chloride O (oil) and has been formed in advance by injection molding.The rear cover 7 has an opening in the center as shown in FIG. It has a back plate 7b on which the lower a is formed, and ribs (protrusions) 7c and '7d that stand up from the inner surface at the outer edge and inner edge of the back plate 7b, respectively.Each rib 7c
, 7 d has multiple holes (locking parts)? ew7f is formed. Further, in the back plate 7b, the rib 7 at the outer edge
Overlap portions 7g that cover the edges of the front cover 6 are located outside of c and inside of the ribs 7d at the inner edge.
+7h.

The rear cover 7 is set on the male die 12 by vacuum suction. In that case, each of the above overlap portions 7g+7
h is set by flipping it outward against the elasticity of the material of the rear cover 7.

Next, the positioning pin lle provided in the upper mold 11C of the female mold 11 is inserted into the pin hole 12a provided in the male mold 12, and the female mold 11 with the front cover 6 and the stay 3 set therein, and the rear cover The male mold 12 in which the mold 7 is set is clamped as shown in FIG. Then, each overlap portion 7g, 711 of the rear cover 7 is brought into contact with the film 6b of the front cover 6 set on the tapered portion 11c of the female mold 11, respectively.

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, foamable urethane fh (fat) is injected into the cavity 8 through a gate (not shown) and foamed to form a foam 4 made of 7 ohm urethane.

During the formation process, the foam 4 adheres to the film 6b of the front cover 6 and to the inner surface of the rear cover 7 due to its own adhesive properties. As a result, the front cover 6 and the rear cover 7 are joined through the foam 4. In particular, in the rear cover 7, the urethane 7 ohm is formed into ribs 7e, ? d multiple holes 7
e, 7f, and these holes 7e, ? The urethane foam in f integrally connects the urethane 7 ohms located on both sides of each rib 7c, 7d.

As a result, the rear cover 7 and the foam 4 are bonded not only by the aforementioned adhesive means, but also by each hole 7e.

The rear cover 7 will not separate from the foam body 4 because they will be locked to each other via 7f and firmly joined.

Further, in this embodiment, the upper opening 6 of the front cover 6
c (shown in FIG. 1) is formed by being squeezed by the constriction part 11b of the female mold 11, and after forming the foam 4, there is a foam inside the front cover 6 that has shape retention properties. Since the foam body 4 is in the stored state, the foam body 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, the female mold 11 and the male mold 12 are opened, and the front cover 6 disposed on the flat portion lid of the insert 11C is cut and removed. Furthermore, the lower mold 11A is connected to the upper mold 11B and the insert 11.
The unfinished headrest 1 separated from C is molded into the lower mold 1.
Move away from 1A.

Then, the headrest 1 is assembled into the upper mold 11B and the insert 11.
Then, the film 6a and the film 6b that were placed 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.
7h covers the edge of the opening 6C of the front cover 6 from the outside and fits tightly.

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 date after the mold is clamped, and foamed. Alternatively, the foamable urethane resin may be injected, 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, the occupant in the rear seat is not subjected to pressure. Particularly, when the front passenger seat is vacant, the passenger in the rear seat can look around the front of the vehicle through the through hole 2a, and is extremely comfortable.

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

Further, there is no seam in the trim 6a of the front cover 6, and the edge of the opening 6C of the front cover 6 is covered and hidden by the overlap portions 7g+7h of the rear cover 7, and the overlap portions 7g, 7h are hidden. Because of the elasticity of the soft resin, the headrest 1 is in close contact with the edge of the opening 6c of the front cover 6, so the design of the headrest 1 is extremely high.

FIGS. 7 and 8 respectively show embodiments of the protrusion and the locking portion provided on the rear cover 7. FIG.

In the embodiment shown in FIG.
A rib 71 having an inverted cross section as a protrusion stands up from b. The rib 71 includes an upright portion 71a that extends integrally from the back plate 7b#-, and a locking portion 71b that is bent at a right angle at the tip of the upright portion 71a. If the headrest 1 is manufactured using this rear cover 7 in the same manner as in the first embodiment, when the foamable urethane resin is injected into the cavity 8 and completely oiled, the urethane foam will be attached to the rear cover 7. The foam 4 also enters the back side of the stop portion 71b and is formed so as to wrap around the rib 71. As a result, similarly to the first embodiment, the rear cover 7 and the foam body 4 are locked to each other,
The rear cover 7 will not separate from the foam body 4.

In the embodiment shown in FIG. 8, the back plate 7 of the rear cover 7
From b, mushroom-shaped protrusions 72 are scattered in an upright manner. The protrusion 72 includes a substantially conical leg portion 72a that integrally extends from the back plate 7b, and an umbrella-shaped head (locking portion) 72b# formed at the tip of the leg portion 72a. 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 3 and foamed, the 7 ohm urethane will wrap around the protrusion 72. A foam 4 is formed. The head 72
b has the same effect as the locking portion 71b in the second embodiment.

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, the double-strength bars of 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.

Furthermore, in each of the above embodiments, vacuum forming is performed using a mold (female mold), and the first cover is molded and set into the mold at the same time. 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 a headrest of an automobile, but may also be an interior part of a vehicle such as an armrest or a seat backrest, and can also be applied to things other than vehicles.

[Effect 1 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 the conventional sewing method.

In addition, the bonding state between the cover provided with the protrusion and the foam is such that the foam formed in the cavity enters the locking part or wraps around the locking part, so the cover and the foam 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 force bars are made of different materials. It is also possible to manufacture bodies.

Therefore, the cushion body can be manufactured by this manufacturing method regardless of the material of the cover.

[Brief explanation of the drawing]

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 of the mold before clamping. FIG. 3 is a sectional view of the headrest as a completed cushion body, FIG. 4 is a perspective view of the rear cover as the second cover, FIG. 5 is a perspective view of the stay, and FIG. The figure 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 using a conventional headrest manufacturing method, and FIG. 10 is a perspective view of the same headrest. DESCRIPTION OF SYMBOLS 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... hollow part, 1
1.12...Mold, 71...Protrusion (rib), 7
2... Projection body, 71b... Locking part, 72b...
Locking part (head).

Claims (1)

[Claims] 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 extending into the cavity is provided, and a locking portion for the foam is formed on the protrusion, and a first cover and a second cover are respectively set in each of the molds and the molds are clamped. , a foamable resin is injected into the cavity formed when the mold is clamped and foamed to form a foam, and the first cover and the second cover are joined via this foam. A method for manufacturing a cushion body.