JPH11216767A - Hollow double wall structure and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate to grasp insert members from the outside and to take them out when a hollow double wall structure is discarded, and to surely classify a plastic material and a metal material. SOLUTION: A hollow double wall structure 1 is constituted of a surface wall 2, a back wall 3 facing the surface wall 2 at an interval and surrounding walls 4 forming a hollow part between the surface wall 2 and the back wall 3. Insert members 7 in a continuous length are inserted between facing surrounding walls 4 in the hollow part. The inserting sites for the insert members 7 on the facing surrounding walls 4 are opened outside and the end faces of the insert members are exposed outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow double-walled structure obtained by blow molding a thermoplastic, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, an inner rib formed in a hollow portion of a plastic hollow double-walled structure constituting an interior wall, a partition, a door of a building, a floor trunk lid of an automobile, a rear parcel shelf, or the like. A technique for improving strength and rigidity by inserting a flat and curved metal rod into the plate is described in JP-A-9-155957.

[0003]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 9-15 / 1997
The technology described in Japanese Patent No. 5957 was developed by the present applicant, but as a result of subsequent studies, it has been found that the following problems mainly exist in blow molding.

That is, in a case where a metal rod is inserted into a plastic molded body such as a hollow double-walled structure of this type, a plastic material and a metal material are reused at the time of disposal, after recycling the material. It is necessary to separate the metal material from the plastic material because the metal body is completely buried inside the plastic molding and the metal body is not visible at all from the outside. Work is not easy.

Therefore, the present invention is intended to solve the above-mentioned problem, and even if the strength and the rigidity are improved by inserting a long insert member, the present invention is aimed at solving the problem. An opening is provided in the surrounding wall where the insert member is inserted, and both end surfaces of the insert member are exposed to the outside, so that when the hollow double-walled structure is disposed of, the insert member can be easily grasped and taken out from the outside. It is another object of the present invention to reliably separate a plastic material and a metal material.

[0006]

In order to achieve the above object, a hollow double-walled structure according to the present invention comprises a front wall, a back wall opposed to the front wall at an interval, a front wall and a back wall. And a peripheral wall forming a hollow part between the hollow part and a hollow insert member inserted into the hollow part between the opposing peripheral walls. The insertion portion of the insert member on the opposing peripheral wall is open to the outside, and the end face of the insert member is exposed to the outside. The insert member is surrounded by the surrounding wall integrally connected to the back wall and held by the back wall. It is characterized by having been done.

[0007] The hollow double-walled structure according to the present invention comprises:
In the above configuration, the opening in the peripheral wall is sealed with a seal member.

The method of manufacturing a hollow double-walled structure according to the present invention comprises a front wall, a back wall opposed to the front wall at a distance, and a periphery forming a hollow portion between the front wall and the back wall. A method of blow molding a hollow double-walled structure composed of a wall and
A holding member operably provided at a position facing each other in a cavity of a mold forming a back wall of a pair of split molds holds both ends of a long insert member in the mold in advance. A hollow double-walled structure in which an elongated insert member is inserted between opposing peripheral walls by blow molding and then surrounded by an enclosing wall integrally connected to the back wall and held by the back wall is formed by blow molding. And obtaining a hollow double-walled structure in which the insertion portion of the insert member on the opposing peripheral wall is open to the outside and the end face of the insert member is exposed to the outside by retreating the holding member after blow molding. It is characterized by the following.

[0009]

1 to 4 show a hollow double-wall structure according to an embodiment of the present invention. FIG. 1 is an overall perspective view as viewed from the back side, and FIG. Enlarged view of part B of
FIG. 3 is an enlarged sectional view taken along line CC of FIG. 1, and FIG. 4 is a sectional view taken along line AA of FIG.
It is a line expanded sectional view.

FIGS. 5 and 6 show a blow molding mode of a hollow double-walled structure according to an embodiment of the present invention. FIG. 5 is a cross-sectional view showing a process before the mold is closed, and FIG. It is sectional drawing which shows the process of FIG.

In FIG. 1, reference numeral 1 denotes a hollow double-walled structure. The hollow double-walled structure 1 has a panel shape.
Reference numeral 2 denotes a front wall, 3 denotes a back wall, and 4 denotes a peripheral wall. As shown in FIG. 4, the back wall 3 is opposed to the front wall 2 at an interval. A hollow portion 5 is formed between 2 and the back wall 3. A fiber sheet 6 is attached to the entire surface of the front wall 2 so as to cover a part of the peripheral wall 4.
The fiber sheet 6 is attached in a blow molding step of the hollow double-wall structure 1 as described later.

A long insert member 7 is inserted into the hollow portion 5 of the hollow double-wall structure 1 so as to extend between the opposing peripheral walls 4. The insert member 7 is a straight metal pipe. Insert member 7
Is a surrounding wall 8 integrally connected to the back wall 3 as shown in FIG.
The peripheral surface is surrounded and is integral with the back wall 3.

As shown in FIGS. 2 and 3, the insertion portion of the insert member 7 of the opposed peripheral wall 4 is open to the outside. Reference numeral 9 denotes an opening concave portion, and reference numeral 10 denotes an end surface of the insert member 7 which is exposed to the outside.

Reference numeral 11 denotes a cap-shaped sealing member. The opening of the peripheral wall 4 has a sealing member 11
And sealing is performed so that the opening concave portion 9 is substantially flush with the peripheral wall 4. Therefore, if the seal member 11 is removed, the opening concave portion 9 opens to the outside, and the insert member 7
Is exposed to the outside, the insert member 7 can be reliably grasped from the outside.

In the illustrated embodiment, the insert member 7
Although a pipe having a circular cross section is illustrated as an example, the insert member 7 is not limited to this.
It may be a square tube, a polygonal tube, an elliptical tube, or a solid tube.

The hollow double-walled structure 1 according to the present invention comprises AB
S resin, modified polyphenylene oxide resin, polycarbonate resin, polyamide resin, polypropylene resin,
It is made of a blowable thermoplastic resin such as a polyethylene resin.

The hollow double-wall structure 1 according to the present invention is shown in FIG.
And blow molding as shown in FIG. Reference numeral 12 denotes one split mold for molding the front wall 2, 13 denotes the other split mold for forming the back wall 3, and an insert member 7 is provided at a portion of the cavity 14 of the other split mold 13 which faces each other. The holding members 15, 15 which are fitted to and held by both ends of the camera are provided so as to be able to protrude and retract. This holding member 15.15
It is operated by the air cylinders 16 and 16 respectively.

At the time of blow molding, as shown in FIG. 5, both ends of the insert member 7 are previously held by the holding members 15 and inserted. In addition, the fiber sheet 6
Are arranged so as to face one mold 12. Next, a parison 18 is arranged between the extrusion head 17 and the molds 12 and 13.

Next, as shown in FIG. 6, after closing the mold, a pressurized fluid is blown into the parison 18 to perform blow molding.
After the blow molding, the surfaces of the front wall 2, the back wall 3 and the peripheral wall 4 constituting the hollow double-walled structure 1 are cooled by cooling the split dies 12, 13, and cooled and solidified to such an extent that the shape is maintained. In short, the holding members 15, 15 are retracted by the air cylinders 16, 16 and pulled out from both ends of the insert member 7, and the mold is opened to separate the hollow double-walled structure 1 into the divided molds 12, 12.
Remove from 13. Then, the seal member 11 is fitted into the opening concave portion 9 of the peripheral wall 4 opposed thereto.

As described above, in the blow-molded hollow double-walled structure 1, the insert member 7 inserted into the hollow portion 5 causes the seal member 11 to pass through the opening concave portion 9 of the peripheral wall 4 facing the same. If it is removed, the end face 10 of the insert member 7 can be grasped from the outside, so that it is easy to insert the insert member 7 into the hollow double-walled structure 1 when the hollow double-walled structure 1 is discarded. Can be easily recognized and can be easily separated. At this time, the insert member 7 is inserted into the opening concave portion 9 and the rod-shaped tool is inserted into the concave portion 9 to strike out the insert member 7 from the hollow double-wall structure 1.
Can be easily removed.

[0021]

According to the present invention, even if the strength and the rigidity are improved by inserting a long insert member, an opening is formed in a portion of the opposing peripheral wall where the insert member is inserted. By exposing both end surfaces of the insert member to the outside, when the hollow double-walled structure is discarded, it is easy to grasp and take out the insert member from the outside, and the plastic material and the metal material are reliably separated. A hollow double-walled structure is obtained which can be

[Brief description of the drawings]

FIG. 1 is a perspective view of a hollow double-walled structure according to the present invention as viewed from the back side.

FIG. 2 is an enlarged perspective view of a portion B in FIG.

FIG. 3 is an enlarged sectional view taken along line CC of FIG. 1;

FIG. 4 is an enlarged sectional view taken along line AA of FIG. 1;

FIG. 5 is a partial cross-sectional view showing a blow molding mode of the hollow double-walled structure according to the embodiment of the present invention, showing a step before closing the mold.

FIG. 6 is a cross-sectional view showing a step after the mold is closed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow double wall structure 2 Front wall 3 Back wall 4 Peripheral wall 5 Hollow part 6 Fiber sheet 7 Insert member 8 Surrounding wall 9 Opening concave part 10 End face of insert member 11 Seal member 12 One split mold 13 The other split mold Mold 14 cavity 15 holding member 16 air cylinder 17 extrusion head 18 parison

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 24:00

Claims (3)

[Claims] 1. A hollow double-walled structure comprising a front wall, a back wall facing the front wall at an interval, and a peripheral wall forming a hollow portion between the front wall and the back wall. A long insert member is inserted into the hollow portion between the opposing peripheral walls, and the insertion portion of the insert member on the opposing peripheral wall is open to the outside, so that the end face of the insert member is external. Wherein the insert member is surrounded by an enclosing wall integrally connected to the back wall and held by the back wall. 2. The hollow double-wall structure according to claim 1, wherein the opening of the peripheral wall is sealed with a seal member. 3. A hollow double-walled structure comprising a front wall, a back wall facing the front wall at an interval, and a peripheral wall forming a hollow portion between the front wall and the back wall. A method of performing blow molding, wherein a long insert member is inserted into a mold by a holding member operably provided in an opposing portion of a cavity of a mold forming a back wall of a pair of split molds. Are inserted in advance while holding both ends of the hollow member, and then a long insert member is inserted between the peripheral walls facing each other by blow molding, and the hollow member is surrounded by the surrounding wall integrally connected to the back wall and held by the back wall. By forming the heavy wall structure and retreating the holding member after the blow molding, the hollow portion in which the insertion portion of the insert member on the opposing peripheral wall is open to the outside and the end face of the insert member is exposed to the outside. To get a heavy wall structure And a method for producing a hollow double-walled structure.