JP2974948B2 - Manufacturing method of automobile seat back - 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 for manufacturing a seat back for an automobile having a downwardly opened bag portion on the upper rear side and the shock absorbing pad embedded in a side portion.

[0002]

2. Description of the Related Art As a seat back for an automobile, as shown in FIG.
In some cases, the upper portion of the seat frame F is inserted into the bag portion 81. Reference numeral 82 denotes a headrest stay insertion hole, and 8
Reference numeral 3 denotes fins formed inward on both sides on the back side of the seat back 80 to wrap the seat frame F.

In recent years, in order to improve the occupant's posture during running and to further protect the occupant from a collision from the side of the automobile, the seat back 80 shown in FIG. A shock absorbing pad 85 made of rigid urethane foam, foamed polypropylene or the like is embedded in the side portions 84, 84.

[0004] Conventionally, the manufacture of a seat back having the bag portion 81 at the upper portion on the back side is performed using a molding die 86 as shown in FIGS. The molding die 86 includes a lower die 87, an upper die 88, and a middle die 89 suspended between the upper die 88 and inserted between the upper die 88 and the lower die 87 when the die is closed. The middle mold 89 is for forming the bag portion 81, and has a rod-shaped body 90 that forms the headrest stay insertion hole 82 at the tip thereof. Then, as shown in FIG. 11, a foaming raw material P such as a urethane raw material is injected into the lower mold 87, and the mold is closed and foamed to manufacture the seat back.

[0005] For the manufacture of a seat back in which the shock absorbing pad 85 is embedded, a method of bonding the shock absorbing pad after removing the molded product from the molding die 86 or a method of attaching the shock absorbing pad to the inside of the molding die 86 is employed. There is a method in which the seat back in which the shock absorbing pad is embedded is foamed by disposing and foaming the foaming raw material with the foaming material 85 disposed therein.

[0006] However, the method of bonding the shock absorbing pad later does not only require extra bonding work, but also
There is a problem that it is not easy to adhere to a fixed position. Furthermore, in order to be able to bond the shock-absorbing pad later, the part to be bonded must be formed into a recess having a size corresponding to the shock-absorbing pad, and the molded article must be foam-molded. There is a problem that the shape is generated and it is difficult to remove the mold.

On the other hand, as a method of foaming and molding a seat back by arranging an impact absorbing pad in the mold, FIG.
As shown in FIG. 2, a pin 91 for receiving the shock absorbing pad 85 is erected on the lower die 90, and the shock absorbing pad 85 is placed on the pin 91 for foam molding, and as shown in FIG. There is known a method in which a part of a shock absorbing pad 85 is sandwiched by a clip 94 provided on a middle mold 92 and foamed.

However, in the method of mounting the shock absorbing pad on the lower pin, it is difficult to position the shock absorbing pad, and there is a problem that the shock absorbing pad is likely to be displaced or tilted when the mold is closed. . In addition, since a hole is opened in the surface of the seat back by the lower pin, there is also a problem that the skin covered on the seat back after the mold release is depressed at the portion of the hole, and the appearance is impaired.

On the other hand, in the method of sandwiching the shock-absorbing pad with the clip, since the shock-absorbing pad must be inserted while the clip is being spread, the operation is troublesome, and furthermore, a crack is formed in the clip-clamping portion of the shock-absorbing pad. In some cases, cracks need to be repaired later. Further, since the clip is exposed, the foaming material adheres to the clip and is hardened, so that a problem that hinders release of the seat back is likely to occur. When a back reinforcing material made of a woven fabric or the like for reinforcing the back surface of the seat back is placed on the surface of the middle mold and foamed, the back reinforcing material simply absorbs the shock at the shock absorbing pad arrangement portion. Since the clip is sandwiched between the pad and the middle mold and is not directly locked to the middle mold, there is also a problem that the back surface reinforcing material is easily shifted when the shock absorbing pad is sandwiched by the clip, and the shock absorbing pad is also easily shifted.

[0010]

SUMMARY OF THE INVENTION The present invention solves all of the above-mentioned problems, and makes it possible to easily and accurately set the position.
Moreover, it is an object of the present invention to provide a method of manufacturing an automobile seat back in which a shock absorbing pad can be correctly embedded.

[0011]

SUMMARY OF THE INVENTION According to the present invention, a shock absorbing pad is arranged in a mold having a structure in which a middle mold is inserted between a lower mold and an upper mold, and a foaming material is injected into the mold to form foam. By having a downwardly opened bag part on the back side upper part,
When manufacturing an automobile seat back having the impact absorbing pad embedded in a side portion, a projection is provided on the side of the middle die, and a recess capable of being press-fitted into the projection is formed on the surface of the impact absorbing pad in advance. The middle-sized projection is press-fitted into a recess of the shock absorbing pad, and the shock absorbing pad is detachably attached to the middle size.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view of a molding die showing an example of a method of manufacturing a seat back according to the present invention, FIG. 2 is a cross-sectional view showing an enlarged part thereof, and FIG. FIG. 4 is an enlarged perspective view showing a projection in the same embodiment when the pad is mounted, FIG. 5 is an enlarged perspective view showing a projection of another example, and FIG. It is a perspective view of the side part of the middle size in which the projection of other examples was formed.

The molding die 10 shown in FIGS. 1 and 2 comprises a lower die 11, an upper die 21 and a middle die 31, which are shown in FIGS.
Similarly to the molding die 86 indicated by reference numeral 0, the middle die 31 is opened and closed while being suspended from the upper die 21, and the middle die 31 is inserted between the lower die 11 and the upper die 21 by closing. In addition to these structures, in the molding die 10, the side portions 32 of the middle die 31 are used.
A projection 33 for mounting a shock absorbing pad is formed toward the mold surface 12 of the lower mold 11. The protrusion 33 is press-fitted into a concave portion 52 formed in a shock absorbing pad 51 described later, and comes into pressure contact with the inner surface of the concave portion 52 so as to press the shock absorbing pad 51.
Is properly held in the middle mold 31. In addition,
In this embodiment, the side portion 32 of the middle die 31 where the protrusion 33 is formed has a raised shape to form a recess for accommodating the seat mounting portion 95 of the seat frame F shown in FIG.

The protrusions 33 have various shapes which come into pressure contact with the inner surface of the concave portion 52 of the shock absorbing pad 51. In this embodiment, as shown by a two-dot chain line S in FIG. The shape is substantially rectangular. The projection 33 having a rectangular outer peripheral shape on one side is long in one direction, and has a flat side surface. 31
There is an advantage that can be held. In particular, when the number of protrusions is plural, the number of recesses of the shock absorbing pad formed corresponding to the protrusions is also plural, so that the positioning of the protrusions and the concave portion is easily troublesome. Therefore, it is preferable to provide one having a substantially rectangular outer peripheral shape, such as the protrusion 33 of this embodiment.

The projection 33 is provided on the shock absorbing pad 5.
In order to prevent the peripheral edge of the concave portion 52 from being damaged when being press-fitted into the first concave portion 52, as shown in FIG. In order to facilitate press-fitting, it is preferable that the side surface shape be a large trapezoid at the base and a small trapezoid at the tip. In this embodiment, the width A of the base is 10 mm, the width a of the tip is 9 mm, the length B of the base is 24 mm, the length b of the tip is 16 mm, and the distance (height) between the base and the tip is 11 mm. I have.

In the middle die 31, a rod 37 for forming a headrest stay insertion hole is formed at the tip, and a set pin 38 for holding a back reinforcing member 61 is provided upright on the front surface. ing.

Next, an example of manufacturing a seat back using the molding die 10 will be described. First, the upper mold 21 is raised, and the back surface reinforcing member 61 is set on the middle mold 31 as shown in FIG. This back reinforcing member 61 is for preventing the seat frame F shown in FIG. 7 from directly contacting the foam of the seat back and damaging the foam, and is made of a flexible material such as a nonwoven fabric. . The back reinforcing member 61 has a hole 62 for passing the protrusion 33 in addition to a hole 62 for passing the medium-sized rod 37 and a hole 63 for passing the set pin 38. I have. In this hole 64, the protrusion 3
3, the back reinforcing material 61 is fixed in position on the side of the middle mold 31 on which the shock absorbing pad 51 is mounted, so that the back reinforcing material 61 does not shift when the shock absorbing pad 51 is mounted thereafter. The correct mounting of the shock absorbing pad 51 can be assisted.

Subsequently, the shock absorbing pad 51 is attached to the middle mold 3
1 is attached to the side part 32. This shock absorbing pad 51
It is made of a foam that is broken by a large impact and absorbs the impact, for example, a rigid urethane foam or the like, and is formed into a required shape in advance. In addition, the protrusion 3 of the middle die 31 is provided on the middle mounting surface 53 of the shock absorbing pad 51.
A concave portion 52 into which 3 can be pressed is formed in advance.
Then, by pressing the protrusion 33 into the recess 52, the shock absorbing pad 51 is positioned at the correct position of the middle mold 31,
In addition, the shock absorbing pad 51 is mounted in a correct posture, and the displacement of the shock absorbing pad 51 is prevented even when the mold is closed thereafter. Further, since the back surface reinforcing member 61 is also sandwiched between the middle mold 31 and the shock absorbing pad 51 on the side of the middle mold 31, it does not separate from the middle mold 31 when the mold is closed.

At least a part of the inner surface of the concave portion 52 is in pressure contact with the surface of the projection 33, and the shock absorbing pad 51 is held on the projection 33 by the frictional resistance of the pressure contact surface.
The dimension of the recess 52 is such that the distance between at least one pair of opposing inner surfaces of the recess 52 is the distance between the inner surface and the corresponding outer surface of the projection 33 so that the protrusion 33 can be pressed against the recess 52. Slightly smaller than The degree of the reduction is set such that the protrusion 33 can be press-fitted with a small force and the frictional resistance can be obtained such that the shock absorbing pad 51 does not drop by its own weight. Therefore, the degree of the reduction depends on the material of the shock absorbing pad 51 and the like.
It is about 0.5 to 1.0 mm. Recess 5 of this embodiment
2 has a rectangular inner peripheral shape having an inner surface substantially similar to the outer surface of the protrusion 33, and the width A of the protrusion 33
The distance between the inner surface of the recess 52 corresponding to (a) is A (a).
0.5 mm smaller than the value of
And the distance between the inner surfaces of the concave portions 52 corresponding to the above is set equal to B (b).

The shock-absorbing pad 51 having the concave portion 52 is formed in a shock-absorbing-pad forming die having a protrusion corresponding to the concave portion 52 on a mold surface, compared to a shock-absorbing pad 51 having a concave portion formed by a cutting tool or the like. It is preferable to inject a foaming material into the foamed material and foam the material so as to form a mold having the concave portion 52 (molding). In the molded shock absorbing pad 51, the surface portion formed in contact with the mold surface of the shock absorbing pad forming die becomes a high-density skin layer, and the inside becomes a low-density foam layer. for that reason,
Since the surface of the concave portion 52 is also formed of a high-density skin layer and has high strength, when the surface of the concave portion 52 is pressed by the press-fitting, a restoring force is reliably generated, and the frictional resistance becomes sufficient. And exhibit good shock absorbing pad retention.

Further, the shock absorbing pad 51 of this embodiment
The medium mounting surface 53 has a substantially L-shaped concave shape, and the medium mounting surface 53 is disposed on the side surface 39 of the medium and the medium surface 40 that is bent substantially at a right angle from the side surface 39. Has become. Therefore, this shock absorbing pad 51
When mounting the middle mold 31 on the middle mold 31, one surface 54 of the middle mold mounting surface 53 comes into contact with the side surface 39 of the middle mold 31 via the back surface reinforcing member 61 to perform a guiding action. Can be easily adjusted. further,
In the shock absorbing pad 51 of this embodiment, since the two surfaces 54 and 55 of the middle-sized mounting surface 53 abut the side surface 39 and the front surface 40 of the middle-sized die 31 via the back surface reinforcing member 61, the posture is more reliably correct. Is held.

Thereafter, a foaming material P such as a polyurethane material
Is poured into the lower mold 11, the upper mold 21 is lowered, and the mold 10 is closed. Thereby, the middle mold 31 is inserted between the lower mold 11 and the upper mold 21 as shown in FIG. 1 and FIG. 2, and the shock absorbing pad 51 is correctly arranged in the mold 10 and held without displacement. And the foaming raw material P
Are foamed and filled in the mold 10 to form a seat back in which the shock absorbing pad 51 is embedded in the side. At the time of foaming, the concave portion 52 of the shock absorbing pad 51 and the middle mold 3
1 is in a state of being concealed by the shock absorbing pad 51 and the middle mold 31, so that the foaming raw material P
Does not penetrate and adhere to the projection 33.
In addition, since the back surface reinforcing member 61 interposed between the side surface 39 of the middle mold 31 and one surface 54 of the middle mounting surface 53 of the shock absorbing pad 51 acts as a sealing material, the foaming raw material P It can be more reliably prevented from entering the recess 52 and the projection 33.

Thereafter, the upper mold 21 is raised, the mold 10 is opened, and the seat back in which the shock absorbing pad 51 is embedded is removed. At this time, since the foaming raw material does not adhere to the concave portion 52 of the shock absorbing pad 51 and the protrusion 33 of the middle mold 31 as described above, the removal of the seat back from the mold may be hindered, or the foam may be broken at the time of removing the mold. Absent. The seat back thus obtained is then mounted on a car with the seat frame disposed on the back side and the surface covered with a skin.

Note that, unlike the present invention, the protrusion 33
Alternatively, it is conceivable to manufacture a seat back by holding a shock absorbing pad by piercing the needle into a shock absorbing pad by standing a needle in a medium size, in which case, a needle and a shock absorbing pad are used. And the frictional force between the needle and the shock absorbing pad is also small. Furthermore, the shock-absorbing pad molded as described above has a high-density skin layer on the surface but a low-density brittle foam layer on the inside, so that most of the needles are located in the brittle foam layer. And the shock absorbing pad cannot be held sufficiently. Therefore, when the mold is closed, the shock absorbing pad is likely to be displaced or easily fall off from the middle mold, and there is a problem that a good seat back cannot be obtained.

Further, the projections in the present invention are not limited to those of the above-described embodiment, and the number is not limited to one. FIG.
Shows a projection 71 of another embodiment. The protruding portion 71 has a protruding portion 72 formed on the tip side surface. The protruding portion 72 presses the inner surface of the concave portion 52 of the shock absorbing pad more firmly, so that the pressure contact with the concave portion 52 is further ensured. In this embodiment, the protrusion amount of the protrusion 72 from the side surface 73 is 2 mm, and the vertical width is 5 mm. Reference numeral 74 indicates a middle side.

FIG. 6 shows a projection 75 according to still another embodiment. In this embodiment, the protrusions 75 are formed in a columnar shape, and are provided two on the middle side 76 at a predetermined distance. In this case, it goes without saying that concave portions (not shown) corresponding to the shape of the protrusions 75 are formed in the shock absorbing pad in accordance with the interval between the protrusions. The columnar shape of the protrusion is not limited to the columnar shape as shown in FIG. 6, but may be a prismatic shape. Further, both the columnar protrusion and the protrusion having a substantially rectangular outer peripheral shape shown in FIG. 4 or 5 may be provided on the middle side.

Further, in the above-described embodiment, the case where the seat back in which the shock absorbing pad is embedded on both sides is manufactured, but the manufacturing of the seat back in which the shock absorbing pad is embedded only on one side is also described. This invention applies. In this case, the protrusion is formed only on one side of the middle sized die, and the shock absorbing pad is mounted on the side where the protrusion is formed. Further, in the above-described embodiment, the example in which the back surface reinforcing material is used has been described, but the present invention is also applied to the manufacture of a seat back that does not use the back surface reinforcing material.

[0028]

As described above, according to the manufacturing method of the present invention, the shock absorbing pad can be embedded in the seat back only by mounting the shock absorbing pad on the middle mold and foaming the seat back. Since it is not necessary to bond the shock absorbing pad in a later operation, the operation is simplified.

Further, according to the manufacturing method of the present invention, since the shock absorbing pad is mounted on the middle mold by press-fitting the projection of the middle mold into the concave portion of the shock absorbing pad, the shock absorbing pad can be easily fixed in the molding die. Position. Moreover, since the shock absorbing pad is held in the middle size by the frictional resistance between the outer surface of the projection and the inner surface of the concave portion caused by the press-fitting, the shock absorbing pad does not shift or come off when closing the mold. As a result, it is possible to easily obtain a seat back in which the shock absorbing pad is embedded in a correct position and in a correct posture.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a molding die showing an example of a production method of the present invention.

FIG. 2 is an enlarged sectional view showing a part of FIG. 1;

FIG. 3 is a schematic perspective view of a medium-sized body showing a state where a shock absorbing pad is mounted in the embodiment.

FIG. 4 is an enlarged perspective view showing a protrusion in the embodiment.

FIG. 5 is an enlarged perspective view showing a protrusion of another example.

FIG. 6 is a perspective view showing a middle-sized side portion on which a projection of still another example is formed.

FIG. 7 is a perspective view showing an example of a seat back.

FIG. 8 is a sectional view taken along the line 7-7 in FIG. 6;

FIG. 9 is a cross-sectional view illustrating an example of a seatback forming die.

FIG. 10 is a sectional view showing a mold opening state of the molding die.

FIG. 11 is a perspective view showing a state in which a liquid foaming raw material is injected into a lower mold of the molding die.

FIG. 12 is a cross-sectional view of a lower die showing a conventional arrangement of a shock absorbing pad in a molding die.

FIG. 13 is a cross-sectional view of a molding die showing another example of a conventional arrangement of shock absorbing pads in the molding die.

[Explanation of symbols]

 10: Mold 11: Lower mold 21: Upper mold 31: Middle mold 32: Side 33, 71, 75: Projection 51: Shock absorbing pad 52: Concave 53: Medium mold mounting surface 72: Projection

Continuation of the front page (51) Int.Cl. ⁶ Identification code FIB29L 31:30 (56) References JP-A-57-125026 (JP, A) Fully open 4-128812 (JP, U) Really open Showa 58 −137356 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B29C 39/10 B29C 39/24-39/34 B29C 33/12-33/14 B60N 2/00 A47C 7 / 18

Claims (5)

(57) [Claims] An impact absorbing pad is disposed in a mold having a structure in which a middle mold is inserted between a lower mold and an upper mold, and a foaming material is injected into the mold and foamed to open downward. When manufacturing an automobile seat back having a bag portion on the upper side on the back side and the impact absorbing pad embedded in the side portion, a protrusion is provided on the side of the middle die, and a recess capable of press-fitting the protrusion is provided. Is formed in advance on the surface of the shock-absorbing pad, and the medium-sized protrusion is pressed into a recess of the shock-absorbing pad, and the shock-absorbing pad is detachably attached to the medium-sized sheet. Manufacturing method of bag. 2. The method for manufacturing a seat back for an automobile according to claim 1, wherein the outer periphery of the middle-sized projection has a substantially rectangular shape. 3. The method for manufacturing a seat back for an automobile according to claim 1, wherein the middle-sized projection has a projection on a front end side surface thereof. 4. A method of manufacturing a seat back for an automobile according to claim 1, wherein one or more projections are provided at a portion where the middle-sized shock absorbing pad is mounted. 5. The shock absorbing pad according to any one of claims 1 to 4, wherein a middle mounting surface of the shock absorbing pad is substantially L-shaped and the middle mounting surface is substantially perpendicular to the side surface of the middle die. A method for manufacturing a seat back for an automobile, wherein the method is arranged on a surface of a bent medium size.