JP2981407B2 - Foam mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foaming mold mainly used for molding automobile interior parts such as a center armrest.

[0002]

2. Description of the Related Art As is well known, various interior parts for automobiles are molded from a foamable synthetic resin such as polyurethane foam. This type of automotive interior parts (armrest, console box, etc.) requires a certain level of mechanical strength while using foam to enhance cushioning, softness, etc., and therefore has reinforcing inserts inside. And is integrally molded with the insert. FIG. 6 is a partial perspective view of a foam molded product for a rear center armrest. In an armrest or the like, usually, a mounting shaft 71 to a mating member is protruded outward from a foam molded product A on an iron plate insert. Provided. Therefore, in the foaming mold k for producing them, the parting line PL has to be lowered to the position of the mounting shaft 71 (FIG. 8).

[0003]

However, there is an overhanging portion a of the foam molded product above the mounting shaft, and this portion is equivalent to causing the upper die 91 to form the undercut portion U. As a result, if the foamed molded product remains in the lower mold at the time of opening the mold, the undercut U of the upper mold lifts the overhanging portion a of the molded product, so that the foamed molded product A becomes the overhanging portion a.
Was easy to destroy. Even if the foam molded product is released from the upper mold 91, the foam molded product A
1 had to be peeled off (without forcible removal), and as in the above, there was a possibility that the foamed molded product would be broken. Here, when the undercut portion U has a small dimension L, it may be possible to cope with the forcible removal specification, but when the dimension L is large, the product often breaks when the mold is opened. Needless to say, the formation of the undercut portion U itself has a problem that it depends on forcible removal at the time of opening the mold, resulting in an increase in defective products and an increase in molding time.

SUMMARY OF THE INVENTION The present invention has been made to overcome the above-mentioned problems, and a foamed molded product in which an undercut portion is formed can easily be taken out without forcibly removing the foamed molded product. The purpose is to provide.

[0005]

SUMMARY OF THE INVENTION The gist of the first invention is that the insert mounting shaft projects outward from the foam molded product, and a part of the foam molded product protrudes above the mounting shaft. In a foam molding die according to a foam molded article, an insert forming an undercut portion between the mounting shaft and the overhanging portion is disposed on a lower mold side, and the insert forming the undercut portion is opened by a mold opening. Alternatively, there is provided a foaming mold characterized in that the foaming mold is detached from the lower mold as the product is removed. The foaming mold of the second invention is the first invention, wherein the guide pins are erected on the lower surface of the nest or the nesting device portion of the lower mold, and at a position corresponding to the guide pin of the lower mold or the nest. Forming a drilled hole,
By setting the guide pin in the perforated hole by interposing a coil spring that urges the guide pin upward, when the mold is opened or the product is released, the nest is lifted from the lower mold by the bias of the coil spring. It is characterized by doing. The foaming mold according to the third invention is the foaming mold according to the first invention or the second invention, wherein a dovetail groove is formed in the lower mold and the insert is fitted into the dovetail groove. Characterized by sliding along.

[0006]

When the insert forming the undercut portion is arranged in the lower mold as in the foam molding die of the first invention, the insert is caught by the undercut portion of the foam molded product when the mold is opened or the product is released. Since it is detached from the lower mold together with this, it is possible to easily remove the forcible removal. In addition, if the nest is made to spread outward as it floats, the nest will separate from the foam molded product when the product is demolded or the like. When the insert is set with a coil spring that urges upward as in the second invention, when the mold is opened or the product is released, the insert spontaneously floats due to the repulsive force of the coil spring. No burden. Further, when the insert is incorporated into the dovetail groove as in the third invention, the insert does not come off accidentally and slides only in a predetermined direction, so that there is no useless movement and foam molding is performed. Goes smoothly.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a foaming mold according to the present invention will be described in detail based on embodiments. 1 to 5 show an embodiment of a foaming mold. FIG. 1 is an enlarged sectional view showing the vicinity of a mounting shaft of the foaming mold in which an insert is set. FIG. FIG. 3 is an enlarged sectional view of the foaming mold around the mounting shaft, FIG. 3 is a perspective view of the foamed molded product, FIG. 4 is a schematic perspective view of the lower mold according to the present invention, and FIG. Applies to rear center armrests.

The foaming mold D comprises a lower mold 1, a nest 2 obtained by dividing a part of the lower mold 1, and an upper mold 3. The foam molded product A (rear center armrest) commercialized by the foam molding die D has an insert 7 as shown in FIG.
The mounting shaft 71 protrudes outward from the foamed molded product A, and further, forms a protruding portion a above the mounting shaft 71 where a part of the foamed molded product A swells. An undercut portion U between the mounting shaft 71 of the foam molded product A and the overhang portion a is disposed on the lower mold 1 side.

The lower mold 1 has a cavity surface S which is concave in cross section and forms the majority of the foam molded article A. The lower die 1 is provided with a receiving groove 11 having a semicircular cross section for supporting the mounting shaft 71, and a portion forming an upper undercut portion U from the receiving groove 11 is cut away. The notch shape is as shown in FIG.
The upper side E is arranged in parallel with the side of the lower die 1 to form a substantially inverted triangular V-shaped groove in the depth direction. Reference numeral 12 denotes a perforation hole formed at a position corresponding to a guide pin 21 described later (FIG. 2). Reference numeral 13 denotes a pin that rises from the lower mold 1 and is provided for placing and holding the insert 7 thereon.
When setting the insert 7 in the lower mold 1,
The insert 1 is supported at three points of the pins 1, 11 and the pins 13.

As shown in FIGS. 2 and 5, the insert 2 is a block body that forms an undercut portion U between the projecting portion a of the foam molded product A and the mounting shaft 71. Nest 2 is the above V
When the insert 2 is set in the lower mold 1 by fitting into the groove 14, the notch 15 of the lower mold 1 is filled, and the original lower mold state is completed. Here, as shown in FIG. 3, the undercut portion U includes a mounting shaft 71 at a rear portion of the foam molded product and a projecting portion a above the mounting shaft 71.
Is formed partially between the nesting and the nesting 2 so that all of them can be carried. A guide pin 21 is fixed to the lower surface of the insert 2, and the direction of the guide pin 21 matches the direction in which the insert 2 slides along the V-groove 14. As shown in FIG. 2, the guide pins 21 are provided at an angle so that the nests 2, 2 spread outward from the lower mold 1 and separate from the lower mold 1 as they float from the set state of the lower mold 1. Of course, the contact surface 141 of the V-groove 14 is also inclined, and the insert 2 is separated outward as it floats from the lower mold 2.
The diameter of the guide pin 21 is smaller than the diameter of the drilled hole 12. Therefore, the nest 2 inserts the guide pin 21 into the perforated hole 1.
2 is set in the lower mold 1 in the loosely inserted state. Reference numeral 22 denotes a semicircular recess cut into the lower surface of the insert 2 so that the upper half cylindrical portion of the mounting shaft 71 of the insert 7 can be attached when the insert 1 is set in the lower mold 2. (FIG. 5). Reference numeral 4 denotes a coil spring to be inserted into the guide pin 21. The coil spring 4 is set in a compressed state in the perforated hole 12 so as to apply a force for urging the insert 2 upward, and the insert 2 is set on the lower mold 1. In this embodiment, the guide pin 21 is provided on the lower surface of the insert 2. Alternatively, the guide pin 21 may be provided on the insert device portion of the lower die 1 and a hole may be provided on the lower surface of the insert. it can.

The upper mold 3 is a lid mold for forming an upper surface portion of the foam molded product A. When the upper mold 3 is closed, the upward biasing of the coil spring 4 is suppressed and the insert 2 is housed in a fixed position. 2 forms a cavity c. The cavity c corresponds to the outer shape of the foamed product A. Here, when the parting line PL is indicated by a foamed molded product A, it becomes a chain line in FIG. Reference numeral 5 denotes a hinge, and the upper die 3 has a structure that opens and closes with the hinge 5 as a fulcrum.

The insert 7 has a concave box shape to be a core material of the rear center armrest, and has mounting shafts 71, 71 provided on both side surfaces near the rear end. The mounting shaft 71 is not embedded in the foam 6 even when it becomes the foam molded product A, and protrudes outward (FIG. 3). Reference numeral 72 denotes an opening, which is used to reduce the weight of the insert 7 and to connect the foam 6 with the insert 7 interposed therebetween.

Next, a process for producing a foam molded article A using the foam molding die D having the above-described structure will be described, and its operation will be described. First, the mold 7 is opened and the insert 7 is set in the lower mold 1. The nest 2 is urged by the coil spring 4 and floats above the lower mold 1 (FIG. 5). Therefore, receiving groove 1
Since the recess 1 and the recess 22 are largely open, the insert 7 can be set on the lower mold 1 without difficulty placing the mounting shaft 71 on the receiving groove 11. Next, a foamed resin material such as a liquid urethane foam material is injected into the cavity c of the lower mold 1, and then the upper mold 3 is closed. With the closing of the mold, the upper mold 3 presses the insert 2 downward against the urging of the coil spring 4 and sets it on the lower mold 1 to form a cavity c for the foam molded product A (FIG. 1). By performing foam molding in such a state, a foam molded article A with an integrated insert is completed.

Thereafter, the mold is removed, but when the upper mold 3 is opened by removing the mold, the insert 2 floats under the bias of the coil spring 4 (FIG. 2). At this time, the guide pin 21 is
Is inclined outwardly so as to separate from the foam molded article A, so that the nest 2 having the undercut portion U moves in a direction in which the insert 2 is separated from the foam molded article A. Therefore, the foam molded article A can be easily taken out. Assuming that the foam molded product is lower mold 1
Even when the mold remains, the nest 2 moves outward so as to separate from the foam molded article as described above.

In the foam molding die D constructed as described above, the insert 2 for forming the undercut portion U between the mounting shaft 71 and the overhang portion a is provided by partially dividing the lower die 1. After the foam molding, upon demolding of the foam molded article A,
The insert 2 is easily detached from the lower mold 1, and the foamed molded product A can be taken out without forcibly removing it. Therefore, it contributes to preventing the product from being broken. Further, since it is not necessary to forcibly remove the molding cycle, the productivity is improved without reducing the molding cycle. In addition, since there is no inconvenience even with the undercut portion U, the degree of freedom of the product shape is increased. Further, the insert 2 is set with the coil spring 4 interposed therebetween, and the insert 2 floats away from the lower mold 1 as the mold is opened, so that the foam molded product A is not burdened and is not damaged.

By the way, as shown in FIG. 7, a notch-shaped corner portion F of the lower mold 1 is formed into a dovetail shape by making an acute angle, and a foam molding die of another embodiment having an insert 2 corresponding thereto is provided. Then
It becomes more suitable. The insert 2 is fitted in the dovetail groove, and when the insert is set in the lower mold 1, the cutout 15 of the lower mold 1 is filled to complete the original lower mold state. And dovetail grooves F, F
The contact surface 141 is also inclined, so that the insert 2 is separated outward as it floats from the lower mold 1. Thus, in addition to the above-described functions and effects, in this embodiment, since the insert 2 is fitted and attached to the dovetail groove 14 formed in the lower mold 1, the insert 2 does not come off and fall. Further, there is no useless movement by sliding only in a predetermined direction along the dovetail groove 14,
Foam molding proceeds smoothly.

In the present invention, the present invention is not limited to those shown in the above embodiments, but can be variously changed within the scope of the present invention depending on the purpose and application. In addition to the rear center armrest shown in the embodiment, the present invention can be widely used for manufacturing a foam molded product in which an insert having another mounting shaft is embedded. In such a case,
It goes without saying that the shape, material, etc. of each part can be changed according to the purpose of use, required strength, application, etc. of the foam molded article. The foamed resin material is not limited to the urethane foam material, and a method of injecting the foamed resin material into the cavity after closing the mold may be adopted.

[0018]

As described above, the foaming mold according to the present invention can take out a foamed molded product without forcibly removing it at the time of demolding, even if it has a structure in which an undercut portion is formed.
Excellent effect for quality assurance, productivity improvement, etc.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of the vicinity of a mounting shaft of a foaming mold according to the present invention with an insert set.

FIG. 2 is an enlarged cross-sectional view of a foaming mold around an installation axis which shifts to demolding after foam molding.

FIG. 3 is a perspective view of a foam molded article.

FIG. 4 is a schematic perspective view of a lower mold according to the present invention.

FIG. 5 is an enlarged perspective view of the vicinity of the nest.

FIG. 6 is a partial perspective view of a foam molded article.

FIG. 7 is a schematic perspective view of a lower mold according to another embodiment of the present invention.

FIG. 8 is an enlarged sectional view showing the vicinity of a mounting shaft of a conventional type foam molding die.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower die 12 Drilling hole 14 Dovetail 2 Insertion 21 Guide pin 4 Coil spring 7 Insert 71 Mounting shaft A Foam molded product a Overhanging part D Foam molded die U Undercut

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁶ Identification symbol FI // B29K 105: 04 B29L 31:58 (56) References JP-A-6-179223 (JP, A) JP-A-4-261815 (JP, A) Japanese Utility Model 5-2927 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) B29C 33/44 B29C 33/12 B29C 39/10 B29C 39/34 B29C 67 /twenty two

Claims (3)

(57) [Claims] 1. A foam molding die according to an insert-integrated molding in which an insert mounting shaft projects outside the foam molded product and a part of the foam molded product protrudes above the mounting shaft, An insert forming an undercut portion between the mounting shaft and the overhanging portion is arranged on the lower mold side, and the insert forming the undercut portion is separated from the lower mold with mold opening or product release. A foaming mold, characterized in that: 2. A guide pin is erected on a lower surface of the nest or a lower nesting device, and a perforated hole is formed at a position corresponding to the guide pin of the lower or nest. By setting the guide pin in the perforated hole with a coil spring that urges the pin upward, the nest is lifted from the lower mold by the bias of the coil spring when the mold is opened or the product is released. The foam molding die according to claim 1, wherein 3. The dovetail groove is formed in the lower mold, and the insert is shaped to fit into the dovetail groove, so that the insert slides along the dovetail groove. 2. The foam mold according to 2.