JPH04223111A - Integrally foamed molding of part - Google Patents

Abstract

PURPOSE:To prevent foaming resin from entering the innermost recess of a tubular part even under the presence of scattering in the thickness of skin and of error in the accuracy of molds. CONSTITUTION:A tubular part 10 is fitted in the recess 22 of skin 20 so as to form an annular space 30 between the skin 20 and the outer peripheral surface of the tubular part 10 on the inner side deeper than an annular projection 14. Sealing between the tip of the annular projection 34 made on the cavity surface of a mold 32 is established by pressing the part 26, which is opposite to said annular space 30, of the skin with the tip of the annular projecting part 34, which is formed on the cavity surface of a mold 32. After the pouring of foaming resin in a cavity and the expansion of the resin, the part 26, which is opposite to said annular space 30, of the skin 20 is cut off.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of integrally molding a part and a molded product by foam molding.

0002

[Prior Art] Conventionally, as shown in Japanese Utility Model Application Publication No. 62-173260, a skin molded into a predetermined shape and a hard resin base material foam-molded on the back side of the skin are integrally molded. BACKGROUND ART A molded product is known in which a cylindrical part such as a grill for air blowing is fitted to the above-mentioned hard resin base material in a foam molded product.

However, when a cylindrical part is fitted to a hard resin base material as described above, there is a problem in that the airtightness between the hard resin base material and the cylindrical part is not sufficient.

[0004] Therefore, a skin formed into a predetermined shape having a concave portion concave toward the back side, a hard resin base material placed on the back side of the skin, and a cylindrical part placed in the concave portion of the skin. An integrated foam molded product has been proposed, which is formed by integrally molding. This component-integrated foam molded product is made by fitting the cylindrical part into a recess in the skin, then setting the cylindrical part and the skin in a mold, and then inserting a foaming resin between the cavity surface of the mold and the skin. It is obtained by supplying the foamable resin, and then foaming and curing the foamable resin.

[0005] In this case, if the foamable resin hardens at the back of the cylindrical part, the hard resin at the back of the cylindrical part must be removed after molding. By applying pressure between the annular protrusion formed in the cylindrical part and the cylindrical part, a seal was formed between the annular protrusion of the mold and the outer skin, and the foamed resin was prevented from moving to the inner part of the cylindrical part.

[0006]

[Problems to be Solved by the Invention] However, according to the above molding method, if there is variation in the thickness of the skin or there is an error in the precision of the mold, the gap between the annular protrusion of the mold and the skin may Since the sealing performance is insufficient, there is a problem in that the foamable resin penetrates deep into the cylindrical part due to the foaming pressure.

In view of the above, the present invention aims to prevent the foamable resin from penetrating deep into the cylindrical part even if there are variations in the thickness of the skin or errors in the accuracy of the mold. purpose.

[0008]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention involves fitting a cylindrical part into a recess in the skin so that an annular space is formed between the skin and the cylindrical part. After that,
A seal is formed between the annular protrusion of the mold and the skin by pressing the annular protrusion of the mold against a portion of the epidermis that faces the annular space.

Specifically, the solution taken by the present invention is a cylindrical part having an annular protrusion extending in the circumferential direction on the outer circumferential surface of a cylindrical body, and a recess recessed toward the back side into which the cylindrical part can be fitted. After preparing a skin molded into a predetermined shape having a shape, the cylindrical part is placed in the recess of the skin, and the innermost end of the outer peripheral surface of the cylindrical part and the outer peripheral surface of the annular protrusion are brought into contact with the skin. As a result, an annular space is formed between the outer circumferential surface of the cylindrical part on the inner side of the annular protrusion and the skin, and then the mold and the skin are fitted together. The tip of the annular protrusion formed on the cavity surface of the mold presses the part of the skin that faces the annular space toward the cylindrical part, thereby creating a seal between the tip of the annular protrusion and the skin. After that, a foamable resin is supplied between the cavity surface of the mold and the skin, the foamable resin is foamed and hardened, and then the annular space in the skin is The structure is such that the part facing the is cut.

0010

[Operation] With the above configuration, after forming an annular space between the outer circumferential surface of the cylindrical part on the back side of the annular protrusion and the skin, a part of the skin facing the annular space is formed. The tip of the annular protrusion of the mold presses against the cylindrical part to create a seal between the annular protrusion of the mold and the skin, so there may be variations in the thickness of the skin or errors in the accuracy of the mold. Even if there is, these variations and accuracy errors can be absorbed by deforming the annular space.

[0011] Furthermore, after foaming and curing the foamable resin,
In order to cut the part of the epidermis facing the annular space, the cutting can be performed with the tip of a cutting tool such as a cutter extending into the annular space.

0012

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings.

Although the present invention does not limit the type of integrally foamed molded product to which it is applied, in the following, a cylindrical component 10 consisting of a grill for air blowing as shown in FIG. Automobile door trim A formed in
We will explain how to mold it.

As shown in FIG. 1, the cylindrical component 10 includes a cylindrical main body 12 having a rectangular cylindrical shape, and an annular protrusion 14 having a rectangular cross section extending in the circumferential direction provided on the outer peripheral surface of the cylindrical main body 12. , and a lid member 16 fitted to the inner end (upper side in FIG. 1) of the cylindrical main body 12.

[0015] The cylindrical part 10 having the above structure
After preparing, the cylindrical part 10 is set on the cavity surface 18a of the lower mold 18.

In FIG. 2, reference numeral 20 indicates a concave portion 22 concave toward the back side.
The recess 22 of the skin 20 is located on the outer circumferential surface 12a of the cylindrical body 12 on the front side (lower side in FIG. 2) of the annular protrusion 14 of the cylindrical component 10.
The front end surface 14a and the outer circumferential surface 14 of the annular protrusion 14
The lid member 1 is bent from the bending portion 24 that is bent so as to contact each of
It consists of a tapered portion 26 that extends to a portion that abuts the outer peripheral end of the end surface 16a on the back side of the lid member 16, and a flat portion 28 that contacts the end surface 16a on the back side of the lid member 16.

After preparing the skin 20 formed into the shape described above, the cylindrical part 10 is placed in the recess 22 of the skin 20, and the bent part 24 and flat part 28 of the skin 20 are inserted into the cylindrical part 10. in contact with the tapered part 26 of the skin and the cylindrical part 10
They fit together so that an annular space 30 is formed between them.

In FIG. 3, reference numeral 32 denotes an upper mold as a mold, and the upper mold 32 is used for forming the above-mentioned skin 2 on the cavity surface.
A step-shaped annular protrusion 3 is provided at a portion facing the tapered portion 26 of 0.
It has 4.

Then, the skin 20 and the upper mold 32 are brought relatively close together to form a deep space 36 between the flat part 28 of the skin 20 and the cavity surface of the upper mold 32, and the upper mold 32
The tip of the annular protrusion 34 presses the tapered part 26 of the skin 20 toward the cylindrical component 10, and the pressed tapered part 26 is connected to the inner end of the outer peripheral surface 14b of the annular protrusion 14 and the inner end surface 16a of the lid member 16. It is bent and stretched between the outer peripheral edge of the As a result, the tip of the annular protrusion 34 and the tapered portion 2 of the epidermis 20
6 is sealed.

Next, the cavity surface of the upper mold 32 and the skin 20
After supplying a foamable resin, such as a hard foamable urethane resin, to the area between the inner space 36 and the outside space 36, the hard foamable urethane resin is foamed and cured to form a resin hard base material 38. An integrally foamed molded product 40 consisting of a hard base material 38, a skin 20, and a cylindrical component 10 is obtained. When the hard foamable urethane resin is foamed in this way,
The hard foamable urethane resin is compressed by the upper mold 3 due to its foaming pressure.
The tip of the annular protrusion 34 of the upper mold 32 and the tapered part 2 of the skin 20 are filled between the cavity surface of the mold 2 and the skin 20.
6, so that it does not enter into the inner space 36.

Next, as shown in FIG. 4, the integrally foamed molded product 40 is released from the lower mold 18 and the upper mold 32, and the skin 20 is removed.
The tapered part 26 of is cut with a cutter or the like to remove the lid member 16 and the outer skin 20a on the back side of the lid member 16.
An automobile door trim A shown in is obtained.

[0022]

[Effects of the Invention] As explained above, according to the integral foam molding method of the present invention, an annular space is formed between the outer circumferential surface and the skin on the back side of the annular protrusion in the cylindrical part. After that, the part of the skin facing the annular space is pressed toward the cylindrical part with the tip of the annular projection of the mold to seal between the annular projection and the skin, so that the thickness of the skin is reduced. Variations and precision errors in the mold can be absorbed by the deformation of the annular space, so even if there are variations in the thickness of the skin or errors in the precision of the mold, the foamed resin can be absorbed deep into the cylindrical part. There is no possibility of intrusion.

[0023] Furthermore, in order to cut the part of the epidermis that faces the annular space, the tip of the cutting tool such as a cutter can be advanced into the annular space, so that cutting of the epidermis is possible. It is extremely easy to work with.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a step of setting a cylindrical component in a component integral foam molding method according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a step of fitting a cylindrical component into a recessed part of the skin in the above-mentioned component integral foam molding method.

FIG. 3 is a sectional view showing a step of bringing the skin and the upper die relatively close together in the above-described integral foam molding method.

FIG. 4 is a cross-sectional view showing a step of cutting the skin in the above-described integral foam molding method.

FIG. 5 is a front view of an automobile door trim obtained by the above-described integral foam molding method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10... Cylindrical part 12... Cylindrical main body 14... Annular protrusion part 16... Lid member 20... Skin 22... Recessed part 26... Taper part (part facing the annular space part in outer skin) 30... Annular space part 32... Top Type 34...Annular protrusion

Claims (1)

[Claims] 1. A cylindrical part having an annular protrusion extending in the circumferential direction on the outer circumferential surface of a cylindrical body; a skin molded into a predetermined shape having a recessed part toward the back side into which the cylindrical part can be fitted; After preparing the cylindrical part, the inner peripheral surface of the cylindrical part and the outer periphery of the annular protrusion are brought into contact with the skin, so that the annular protrusion on the cylindrical part is placed in the recess of the skin. The skin is fitted in such a way that an annular space is formed between the outer circumferential surface on the back side of the mold and the skin, and then the mold and the skin are connected to the annular space formed in the cavity surface of the mold. The tip of the protrusion presses the part of the epidermis that faces the annular space towards the cylindrical component to bring them relatively close together so that a seal is formed between the tip of the annular protrusion and the epidermis, and then After supplying a foamable resin between the cavity surface of the mold and the skin, the foamable resin is foamed and cured, and then a portion of the skin facing the annular space is cut. A method for integral foam molding of parts.