Filler tube and manufacturing process for the same

Patent metadata

Field	Value
Publication number	US-2017232838-A1
Application number	US-201715584994-A
Country	US
Kind code	A1
Filing date	May 2, 2017
Priority date	Sep 29, 2015
Publication date	Aug 17, 2017
Grant date	—

Abstract

A filler tube, which is capable of satisfying required functions suitably in compliance with the bellows and non-bellows cylindrical base while securing weld strength and fuel-permeation resistance property in the weld face, is provided. A filler tube includes a non-bellows cylindrical base with a total thickness of from 2 to 4 mm, a bellows with a total thickness of from 0.5 to 3 mm, and a flange having a total thickness of from 3.5 to 5 mm, and including an end face to be welded to a fuel tank. The non-bellows cylindrical base, the bellows, and the flange include inner layers formed so as to have a thickness accounting for from 40 to 60% of the total thicknesses, and formed of high-density polyethylene (or HDPE) serving as the major constituent, intermediate layers exhibiting fuel-permeation resistance property, and outer layers protecting the intermediate layers.

First claim

What is claimed is:

1 . A filler tube to be welded to a fuel tank at an opening thereof, and made of thermoplastic resin;
prior to being welded, the filler tube comprising: a non-bellows cylindrical base with a total thickness of from 2 to 4 mm; a bellows with a total thickness of from 0.5 to 3 mm; and a flange having a total thickness of from 3.5 to 5 mm, and including an end face to be welded to the fuel tank; the base, the bellows and the flange including: an inner layer formed so as to have a thickness accounting for from 40 to 60% of the total thicknesses, and formed of high-density polyethylene (or HDPE) serving as a major constituent thereof; an intermediate layer arranged on an outer peripheral side of the inner layer, and exhibiting fuel-permeation resistance property; and an outer layer arranged on an outer peripheral side of the intermediate layer, and protecting the intermediate layer.

2 . The filler tube according to claim 1 , wherein:
the intermediate layer is formed of any of ethylene-vinyl alcohol copolymer (or EVOH) and polyamide-based (or PA-based) resin serving as a major constituent thereof; and the outer layer is formed of any of high-density polyethylene (or HDPE) and polyamide (or PA-based) resin serving as a major constituent thereof.

3 . The filler tube according to claim 1 , the filler tube further comprising:
a non-bellows-shaped heavy-thickness cylinder with a total thickness of from 4 to 6 mm, wherein the flange protrudes outward radially from an end of the heavy-thickness cylinder in one of sides thereof facing the fuel tank.

4 . The filler tube according to claim 3 , wherein the flange is formed thinner than the heavy-thickness cylinder is.

5 . The filler tube according to claim 4 , wherein the flange further includes:
a tapered portion enlarging radially from the end of the heavy-thickness cylinder in the one of the sides facing the fuel tank; and a circularly annular plate-shaped portion elongating outward radially from an end of the tapered portion in one of sides thereof facing the fuel tank.

6 . The filler tube according to claim 5 , wherein:
the tapered portion, and the circularly annular plate-shaped portion are formed thinner than the heavy-thickness cylinder is; and the circularly annular plate-shaped portion is formed thinner than the tapered portion is.

7 . The filler tube according to claim 3 further comprising a tank-side base portion disposed consecutively at an end of the bellows in one of sides thereof facing the fuel tank, disposed in another one of the sides of the heavy-thickness cylinder opposite to the fuel tank, and serving as part of the base.

8 . The filler tube according to claim 7 , wherein the tank-side base portion is provided with a rib protruding in an annular shape outward radially.

9 . The filler tube according to claim 1 further comprising:
a press-fit base portion disposed at an end of the filler tube in one of sides thereof opposite to the fuel tank, making a site into whose inside a mating member is press fitted, and serving as part of the base; and
a non-press-fit base portion disposed consecutively to the press-fit base portion, and serving as another part of the base.

10 . The filler tube according to claim 9 , wherein the non-press-fit base portion is provided with a bent section whose central axis line is curved.

11 . A manufacturing process for the filler tube according to claim 3 , the manufacturing process comprising:
a primary molding step of using a corrugated mold to mold a primary molded body by corrugation molding; and a secondary molding step of using an outer peripheral mold and an inner peripheral mold to mold the filler tube by performing press processing to the primary molded body; the primary molded body including the base, the bellows, a cylindrical to-be-molded portion serving as a site for the flange before being flare molded, and the heavy-thickness cylinder; the secondary molding step including: a primary-molded-body arrangement step of arranging the primary molded body onto the outer peripheral mold so as to make the outer peripheral mold, which is set at a predetermined temperature, support an outer peripheral face in the heavy-thickness cylinder of the primary molded body; and a flare-molding step of flare molding the flange by inserting the inner peripheral mold, which is set at a higher temperature than the predetermined temperature of the outer peripheral mold, into an inner peripheral side of the to-be-molded portion after the primary-molded-body arrangement step, and then relatively moving the outer peripheral mold and the inner peripheral mold in an axial direction thereof to make an end face of the outer peripheral mold and the inner peripheral mold clamp the to-be-molded portion therebetween in the axial direction.

Assignees

• Sumitomo Riko Co Ltd

Inventors

• Fukuyasu Tomoyuki
• Shimojo Makoto
• Miyajima Atsuo
• Hatanaka Kazuki

Classifications

• B29C49/0022

  characterised by mould return means · CPC title

• B60K2015/047

  Manufacturing of the fuel inlet or connecting elements to fuel inlet, e.g. pipes or venting tubes · CPC title

• B60K15/0406 Primary

  Filler caps for fuel tanks · CPC title

• B29C65/02

  by heating, with or without pressure · CPC title

• B29C65/7841

  Holding or clamping means for handling purposes (clamping means for the purpose of applying pressure on the parts to be joined, in the area to be joined B29C66/81; work holders in general B25B; devices for holding or positioning work for welding metal B23K37/04) · CPC title