Composite molded body and method for manufacturing same

Patent metadata

Field	Value
Publication number	US-9482441-B2
Application number	US-201314387164-A
Country	US
Kind code	B2
Filing date	Mar 18, 2013
Priority date	Apr 19, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A composite molded body includes a main portion formed of resin, a ventilation channel configured within the main portion, a gas permeable membrane, and two inserted members embedded in the main portion. The ventilation channel has a first ventilation path P 1 extending in a direction intersecting the gas permeable membrane and has an opening end leading to the external air, and a second ventilation path extending in a direction different from the direction in which the first ventilation path extends and having an opening end leading to the internal space of the casing. The inserted member forms a portion of the second ventilation path and has a membrane supporting portion formed with a through hole. The through hole constitutes a portion of the first ventilation path, and communicates with the internal space of the casing via the second ventilation path.

First claim

The invention claimed is:

1. A composite molded body that is mountable on or integrated in advance with a casing having an internal space, the composite molded body comprising:
a main portion formed of an injection-moldable resin material;
a ventilation channel configured inside the main portion to allow the internal space of the casing to communicate with external air; and
a gas permeable membrane disposed in a midway portion of the ventilation channel,
wherein the composite molded body further includes an inserted member having at least a portion thereof embedded in the main portion, a portion of the inserted member being exposed to at least one of the internal space of the casing and the external air,
wherein the ventilation channel includes a first ventilation path having the gas permeable membrane at its midway portion, and at least one second ventilation path continuous with the first ventilation path,
wherein the gas permeable membrane is arranged within the first ventilation path so as to block the passing of liquids, liquid droplets, and solid matter through the first ventilation path,
wherein the first ventilation path extends in a direction intersecting the gas permeable membrane and has an opening end leading to the external air or the internal space of the casing,
wherein the second ventilation path extends in a direction non-parallel to the direction in which the first ventilation path extends and has an opening end leading to the internal space of the casing or the external air, at least a portion of the second ventilation path being formed by the inserted member,
wherein the inserted member has a membrane supporting portion having the gas permeable membrane placed thereon and having a through hole formed thereto, and
wherein the through hole constitutes a portion of the first ventilation path and communicates with the internal space of the casing or the external air via the second ventilation path.

2. The composite molded body according to claim 1 ,
wherein the main portion is formed with a ventilation hole that constitutes a portion of the first ventilation path and constitutes the opening end of the first ventilation path, the ventilation hole being adjacent to the through hole of the membrane supporting portion of the inserted member via the gas permeable membrane, and
wherein an inner wall portion of the main portion that forms the ventilation hole is formed with a bonding portion to which the gas permeable membrane is bonded, and an outer peripheral edge of the gas permeable membrane is sandwiched by the bonding portion and the membrane supporting portion of the inserted member.

3. The composite molded body according to claim 2 ,
wherein both a cross-sectional area of the through hole of the membrane supporting portion and a cross-sectional area of the ventilation hole of the main portion are configured to be smaller than an area of the gas permeable membrane, the cross-sectional area of the through hole of the membrane supporting portion is configured to be smaller than the cross-sectional area of the ventilation hole of the main portion, and a step portion is formed at a boundary position between the through hole and the ventilation hole.

4. The composite molded body according to claim 1 ,
wherein the membrane supporting portion of the inserted member has a peripheral wall portion provided so as to surround the through hole, and an internal diameter of the peripheral wall portion is equal to an external diameter of the gas permeable membrane or is larger than the external diameter of the gas permeable membrane.

5. The composite molded body according to claim 1 ,
wherein the inserted member has an extending portion that extends from the membrane supporting portion, the extending portion extending in a direction non-parallel to the direction in which the first ventilation path extends and being formed with at least a portion of the second ventilation path.

6. The composite molded body according to claim 1 ,
wherein the inserted member includes a first inserted member and a second inserted member,
wherein the first inserted member includes the membrane supporting portion formed with the through hole, and
wherein at least one of the first inserted member and the second inserted member is formed with a ventilation groove, and
wherein the ventilation groove forms the second ventilation path by bringing the first and second inserted members into contact with each other, and the second ventilation path formed by the ventilation groove communicates with the first ventilation path formed by the through hole of the first inserted member.

7. The composite molded body according to claim 6 ,
wherein the first inserted member is a resin molded product that is molded in advance, and the second inserted member is a metal component that is molded in advance.

8. The composite molded body according to claim 6 ,
wherein close contact between the first and second inserted members that contacts with each other is assured by a shrinkage force generated when the resin material that forms the main portion shrinks after injection molding.

9. The composite molded body according to claim 1 ,
wherein the inserted member has an elongated plate main portion, and an elongated portion elongating from the plate main portion to one side in its width direction,
wherein at least a root of the elongated portion is bendably formed,
wherein the plate main portion is formed with a ventilation groove for providing at least the second ventilation path, and the elongated portion is formed with the membrane supporting portion and the through hole, and
wherein the through hole and the ventilation groove are formed adjacent to each other via the gas permeable membrane and communicate with each other by folding the elongated portion at the root thereof and superimposing the elongated portion on the plate main portion.

10. The composite molded body according to claim 9 ,
wherein close contact between the plate main portion and the elongated portion that are superimposed on each other is assured by a shrinkage force generated when the resin material that forms the main portion shrinks after injection molding.

11. The composite molded body according to claim 1 ,
wherein a plurality of the second ventilation paths are formed.

12. The composite molded body according to claim 1 ,
wherein the second ventilation path branches at its midway portion.

13. A method for manufacturing a composite molded body that is mountable on or integrated in advance with a casing having an internal space,
the composite molded body comprising:
a main portion formed of an injection-moldable resin material;
a ventilation channel configured inside the main portion to allow the internal space of the casing to communicate with external air;
a gas permeable membrane disposed in a midway portion of the ventilation channel; and
an inserted member having at least a portion thereof embedded in the main portion,
wherein a portion of the inserted member is exposed to at least one of the internal space of the casing and the external air,
the method comprising:
a preparing step of preparing a molding die capable of forming a cavity when the molding die is closed and capable of arranging the inserted member within the cavity;
an arranging step of arranging the inserted member inside the opened molding die and arranging the gas permeable membrane at a desired position by using the inserted member;
a mold closing step of closing the molding die to form the cavity for molding the main portion;
a resin filling step of filling the cavity with a resin material to mold the ma

Assignees

• Tokai Kogyo Co Ltd

Inventors

• Hara Koichi

Classifications

• B29C2045/14131

  using positioning or centering means forming part of the insert · CPC title

• B29C45/14467 Primary

  Joining articles or parts of a single article (B29C45/14377, B29C45/14385, B29C45/14581, B29C45/14614 and B29C45/006 take precedence) · CPC title

• B29C45/14795

  Porous or permeable material, e.g. foam · CPC title

• B29L2031/34

  Electrical apparatus, e.g. sparking plugs or parts thereof · CPC title

• B29K2995/0065

  Permeability to gases · CPC title