JP3171711B2 - Method of manufacturing retractable headrest - Google Patents

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 a retractable headrest in which a pillow portion of a headrest can be rotated back and forth to adjust an inclination angle.

[0002]

2. Description of the Related Art A headrest is mounted on a seat backrest of a vehicle mainly for protecting a head. Among the headrests, the retractable headrest can adjust the angle of the pillow according to the physique and preference of the occupant, so that the pillow can always be set at the correct angle or the desired angle, and is excellent in safety and comfort.

[0003] FIG. 8 shows one that is used as a retractable headrest. The foldable headrest is provided on a pillow 42 covered with a foam such as urethane foam or the like, a seat 44 for mounting a seat having an upper portion embedded in the foam of the pillow 42, and an upper portion of the stay 44. And a retractable device 46 housed in the foam of the pillow 42.

[0004] Conventionally, there are the following methods for manufacturing a retractable headrest having the above structure. First, the folding device above the stay is surrounded by a synthetic resin hollow body by blow molding (hollow molding), and the folding device 46 as shown in FIG.
Is formed. At this time, the stay 44 projects from the bottom of the synthetic resin hollow body 52.

Next, as shown in FIG. 10 showing the bottom surface of the insert 50, the synthetic resin hollow body 52 of the insert is cut off around the stay 44 to form a stay rotating opening 54. Thereafter, the opening 54 for turning the stay is closed with a sealing material such as urethane foam, and the synthetic resin hollow body 52 portion of the insert is set in a foamed cavity (not shown). Then, a foam material such as urethane foam material is injected into the cavity and foamed to form an insert-containing foam in which the periphery of the synthetic resin hollow body 52 is covered with the foam.

Thereafter, the foam including the insert is taken out of the mold, and the foam around the stay is cut off. At the same time, the sealing material is removed and the opening for rotating the stay is opened again, so that the desired retractable headrest is mounted. obtain. The surface of the foam of the obtained retractable headrest is thereafter covered with a skin.

However, in the above-described manufacturing method, when the foam is formed, the foam raw material enters the synthetic resin hollow body through the stay rotating opening of the synthetic resin hollow body, and operates the folding device. It is necessary to prevent it from becoming defective. For this reason, the foam is formed after the opening for the rotation of the stay formed prior to the formation of the foam is once closed with the sealing material. However, a problem that it takes time to install the sealing material and remove the sealing material thereafter. There is. In addition, there is also a problem that the sealing material is deformed by the foaming pressure at the time of forming the foam, and the sealing failure is likely to occur.

[0008]

SUMMARY OF THE INVENTION In view of the above, the present invention has been made in consideration of the above-described problems, and when forming a foam around a synthetic resin hollow body of an insert, a seal is provided at a stay rotating opening of the synthetic resin hollow body. An object of the present invention is to provide a manufacturing method capable of easily and easily manufacturing a foldable headrest without mounting any material.

[0009]

SUMMARY OF THE INVENTION The present invention comprises a step of enclosing a folding device provided on an upper portion of a stay with a hollow body made of synthetic resin by blow molding to form an insert incorporating the folding device. The synthetic resin hollow body portion of the insert is set in a foaming mold cavity, a foam material is injected into the cavity and foamed, and an insert-containing foam in which the periphery of the synthetic resin hollow body is covered with a foam is provided. The present invention relates to a method for manufacturing a retractable headrest, comprising a step of forming and a step of cutting off a part of a synthetic resin hollow body around a stay of the insert-containing foam to form a stay rotation opening.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing a blow molding in one embodiment of the present invention, FIG. 2 is a front view of an insert, FIG. 3 is a view showing a bottom surface of an insert, and FIG. FIG. 5 is an enlarged sectional view of a main part of a foaming mold, FIG. 6 is a cross-sectional view of a foam body including an insert, and FIG.

The method of manufacturing a folding headrest in this embodiment includes a step of forming an insert, a step of forming a foam including an insert, and a step of forming an opening for rotating a stay. The description will be made in the order of the molding process.

In the step of forming the insert, as shown in FIG. 1, the folding device 12 provided above the stay 10 is surrounded by a synthetic resin hollow body 14 as shown in FIG. 2 or 3 by blow molding. To form the insert 15 incorporated in the folding device.

As the folding device 12 on the upper part of the stay, various structures can be used. For example, a stay bent in a substantially U-shape is used, and the bent part of the stay is formed of a metal plate from both sides. So that the clamp body is rotatable with respect to the stay and the clamp body (or the stay) is fixed at a predetermined position by a frictional force between the bent portion of the stay and the clamp body. Can be mentioned.

In the blow molding, a side face of the synthetic resin parison P extruded from the die 16 of the extruder is cut in a parison extruding direction by a cutting cutter (not shown) to form an incision S, and the incision S is formed. Then, the folding device 12 is inserted into the parison P, and then the blow molding die 18 is closed, the blowing nozzle is pierced into the heated parison P, and compressed air is blown to blow the parison P into the blow molding die 1.
8 can be performed by a known method of expanding and curing the inner surface shape. At that time, an oval cylindrical body 20 surrounding the outer periphery of the stay 10 is provided around the stay 10 of the synthetic resin hollow body 14, and a space 21 (shown in FIG. 5) is provided between the stay 10 and the outer peripheral surface of the stay 10. In addition, the major axis D of the ellipse (shown in FIG. 3) is the tilting direction of the tilting device 12 (equal to the rotation direction of the stay).
It is preferable to provide them so that

When the stay 10 is formed of a hollow metal pipe, an air outflow hole is formed in a stay portion inserted into the parison P, and the compressed air is blown into the parison P through the stay 10. Compressed air can be blown into the air. Instead of the tubular parison P, a sheet parison made of two synthetic resin sheets may be used.

The next step of forming the insert-containing foam is as shown in FIG.
The four parts are set in the cavity 24 of the foaming mold 22, and a foam material G such as a urethane foam material is injected into the cavity 24 and foamed, and foamed around the synthetic resin hollow body 14 as shown in FIG. This is to form an insert-containing foam 28 covered with the body 26. At this time, the foam raw material G injected into the cavity 24 foams around the synthetic resin hollow body 14 and does not enter the synthetic resin hollow body 14, so that the internal folding device operates. Does not cause defects.

The stay 10 of the synthetic resin hollow body 14 is
When the columnar cylinder 20 is provided around the periphery, the columnar cylinder 20 is sandwiched between the parting surfaces 23 of the mold 22 as shown in FIG. It is preferable that the protrusion 25 is formed, and the side surface of the columnar cylindrical body 20 is pressed and sealed by the protrusion 25. In that case, the columnar cylinder 2 pressed by the projection 25
0 is the space 2 between the cylindrical body 20 and the stay 10.
1. Pressed inward to deform, the side surface of the columnar cylinder 20 is pressed against the mold parting surface 23 by the restoring force of the columnar cylinder 20 generated by the deformation, and the columnar cylinder 20 and the mold parting are pressed. Seal between the surfaces 23 securely. Therefore, there is no possibility that the foam material G leaks out of the cavity 24 from between the columnar cylindrical body 20 and the mold parting surface 23 and adheres and hardens to the outer peripheral surface of the stay 10.

The step of forming the opening for rotating the stay includes removing the insert-containing foam 28 obtained in the insert-forming foam forming step from the foaming mold 22 and then surrounding the stay 10 of the insert-containing foam 28. Of the synthetic resin hollow body 14 is formed to form a stay rotation opening. At this time, when the columnar cylindrical body 20 is provided around the stay 10, as shown in FIG.
The columnar cylindrical portion 20a protruding from 6 is cut off to form a stay rotation opening 30 in the folding direction of the folding device 12.
In this case, the stay rotation opening 30 is equal to the space 21 shown in FIG. In the case of a synthetic resin hollow body having no columnar cylindrical body 20, since a foam covering the synthetic resin hollow body also exists around the stay, the synthetic resin hollow body around the stay is cut off. At this time, the foam is also cut away to form a stay rotation opening.

By forming the stay rotation opening,
The desired retractable headrest is obtained. In this case, the obtained retractable headrest is in a state where the foam 26 is exposed, and is also referred to as a retractable naked headrest. Thereafter, a bag-shaped outer skin is put on the surface of the foam 26 by sewing or the like.

In the step of forming the insert-enclosed foam, a skin previously formed into a hollow shape by blow molding or the like is set in the cavity, and the synthetic resin hollow body portion of the insert is inserted into the skin. By injecting the foam material into the skin, the skin can be applied to the foam at the same time as the foam is formed. In this case, the skin around the stay is formed with an opening in advance so that the stay can rotate, or cut off together with a part of a synthetic resin hollow body or the like in a subsequent step of forming a stay rotation opening.

[0021]

As shown and described above, according to the present invention, since the foam can be formed in a state where the folding device is sealed, the foam raw material does not adhere and harden to the folding device. No malfunction of the tilting device occurs. further,
As in the prior art, the irrational work of once closing the opening for the rotation of the stay formed in the synthetic resin hollow body with the sealing material, removing the sealing material and re-opening the opening for the rotation of the stay is unnecessary. It is possible to easily and reasonably manufacture a foldable headrest.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state during blow molding according to an embodiment of the present invention.

FIG. 2 is a front view of an insert.

FIG. 3 is a view showing a bottom surface of the insert.

FIG. 4 is a cross-sectional view of a foaming mold showing a state at the time of molding an insert-containing foam.

FIG. 5 is an enlarged sectional view of a main part of a foaming mold.

FIG. 6 is a cross-sectional view of an insert-containing foam.

FIG. 7 is an enlarged sectional view of a main part of the retractable headrest.

FIG. 8 is a perspective view of a retractable headrest.

FIG. 9 is a view showing a tiltable device built-in insert in a conventional manufacturing method.

FIG. 10 is a cross-sectional view showing a bottom surface of an insert after a stay rotation opening is formed in a conventional manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Stay 12 Folding device 14 Synthetic resin hollow body 15 Insert 20 Columnar cylinder 22 Foaming mold 24 Cavity 26 Foam 28 Insert inclusion foam 30 Opening for turning of stay G G Foam raw material

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI // B29K 105: 04 B29L 31:58 (56) References JP-A-56-89214 (JP, A) JP-A-53-65372 (JP, A) JP-A-62-157844 (JP, A) JP-A-59-83632 (JP, A) JP-A-62-5821 (JP, A) JP-A-60-145010 (JP, U) 58) Field surveyed (Int.Cl. ⁷ , DB name) B29C 39/10 B29C 39/22-39/24 A47C 7/38 B60R 21/055 B60N 2/48 B68G 7/06

Claims (4)

(57) [Claims] 1. A step of surrounding a folding device provided on an upper portion of a stay with a synthetic resin hollow body by blow molding to form an insert incorporating the folding device, and a synthetic resin hollow body of the insert. Setting a portion in a cavity of a foaming mold, injecting a foam material into the cavity and foaming to form an insert-enclosed foam in which the periphery of a synthetic resin hollow body is covered with a foam; Cutting a part of the synthetic resin hollow body around the stay of the foam to form a stay rotation opening. 2. The method according to claim 1, wherein in the step of forming the insert-containing foam, after setting the hollow skin in the cavity of the foaming mold, the synthetic resin hollow body portion of the insert is set in the hollow skin in the cavity. Then, a foam material is injected into the hollow skin and foamed integrally with the hollow skin to form an insert-enclosed foam in which the periphery of the synthetic resin hollow body is covered with the foam and the skin. Method of manufacturing a tiltable headrest. 3. The cylindrical body according to claim 1, wherein an elliptical cylindrical body surrounding the outer periphery of the stay is formed in the hollow body made of synthetic resin with a space provided between the hollow body and the outer peripheral surface of the stay. Method of manufacturing a tiltable headrest. 4. The method for manufacturing a retractable headrest according to claim 3, wherein the major axis of the ellipse is the direction in which the folding device can be folded.