JPS63242723A - Filler tube made of synthetic resin - Google Patents

Abstract

PURPOSE:To improve the installation strength of a connection part of a fuel tank by integrally forming a flange part with a filler tube body and making thick the flange part in comparison with the thickness of the filler tube body. CONSTITUTION:A flange part 14 for the connection with a fuel tank 20 is formed integrally with the edge part of a filter tube body 12 made of a synthetic resin as blow molded body. A parison is pressed by a press metal mold which slides in the reverse direction to the parison feeding direction in blow molding, and the flange part 14 having sufficient thickness in comparison with the thickness of the tube body 12 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a filler tube connected to a gasoline inlet of a fuel tank and used for injecting gasoline into the fuel tank.

[Prior art]

Recently, fuel tanks for automobiles have been made of synthetic resin from the viewpoints of weight reduction and flexibility in shape design, and filler tubes connected to fuel tanks have also started to be made of synthetic resin. ing.

The following types of conventional synthetic resin filler tubes are known.

First, as shown in FIG. 9, when molding the filler tube by blow molding, a bulge 4 is formed at the tip of the filler tube body 2, and after molding or molding. Some of them are cut at the position 5 to form a flange 3.

Furthermore, as a second technique, as shown in Fig. 10,
There is a type in which a flange portion is formed by welding a centrally opened disk body 7 manufactured by injection molding or the like to the end of the filler tube body 6.

Furthermore, as a third technique, as shown in Fig. 11,
There is a flange body 8 having an insert part 8A manufactured in advance by injection molding, which is inserted into the end of the filler tube body 9 during blow molding of the filler tube to form the flange part.

[Problem to be solved by the invention]

The flange portion of the filler tube is connected to the fuel tank, for example, with bolts and nuts, and is required to have structural strength as a connecting portion, and is required to have sufficient reliability. However, the above-mentioned conventional technology has the following problems.

In the first technique, since the bulging portion 4 is expanded by blowing, it becomes thinner than the wall thickness of the filler tube body 2, which poses a problem in terms of strength and lacks reliability.

Furthermore, since it is stretched in the radial direction by blowing, the outer part where the flange portion 3 is formed becomes thinner and requires processing to have a uniform thickness, which increases the number of work steps accordingly.

Furthermore, the second technique has a problem with the welding strength of the welded portion and lacks reliability. Further, the disk body 7 forming the flange portion must be manufactured in a separate process, which increases the number of manufacturing steps and increases the cost accordingly.

Further, in the third technique, there is a problem in airtightness at the connection surface of the flange body 8 to the end portion of the filler tube body 9, resulting in a lack of reliability. Furthermore, like the second technique, the flange body 8 must be manufactured in a separate process, which increases costs accordingly.

The present invention has been made in view of the problems of the prior art,
The purpose is to provide a filler tube that has a simple structure, has excellent attachment strength at the connection part with the fuel tank, and is highly reliable.

[Means for solving problems]

Next, the present invention will be explained with reference to FIG. 1, which shows an embodiment of the present invention.

Synthetic resin filler tube body 1 which is a blow molded body
A flange portion 14 for connection to the fuel tank 2o is provided at the end of the fuel tank 2o.
are formed into one. During blow molding, the parison is pressed by a press die that slides in the opposite direction to the parison supply direction to form a flange portion 14 that is sufficiently thicker than the tube body 12.

[Effect]

The flange portion 14 is integrated with the filler tube body 12, and is thicker than the filler tube body 12, so that it can withstand a large fastening force with the fuel tank.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment of the present invention, and is a sectional view showing a state in which a filler tube according to the embodiment is connected to a fuel tank.

In this figure, a filler tube 10 has a structure in which a flange portion 14 is integrally formed at the end of a tube body 12, and is made of synthetic resin such as high-density polyethylene. The flange portion 14 serves as a connection portion to the fuel tank 20, and bolt holes 16 are bored at a plurality of locations in the circumferential direction of the flange portion 14. As will be described later, this flange portion 14 is press-molded by a press mold that slides in the opposite direction to the parison supply direction during blow-molding of the filler tube, and has a sufficiently thick wall compared to the tube body 12, and has a large bolt. It is designed to withstand fastening force. A reference guide part 13 of a size that can just engage with a gasoline inlet 22 of a fuel tank 20, which will be described later, is protruded from a lower position of the flange part 14. It serves as a positioning member when attached to the entrance 22.

Reference numeral 21 is a fastening bolt, 22 is a gasoline inlet of the fuel tank, 23 is a ring-shaped plate disposed around the outer circumference of the gasoline inlet 22, and 23A is a bolt 21t formed on the plate 23! Female thread part which is A joint part, symbol 24 is O ring, symbol 26 is flange part 1
A retainer 28 disposed in contact with 4 is a reinforcing member attached to the inner circumferential wall of the fuel tank so as to surround the gasoline inlet 22 of the fuel tank.

In this manner, in this embodiment, the flange portion 14 is integrated with the filler tube body 12 and has a wall thickness sufficiently larger than that of the filler tube body 12, so that the flange portion 14 can be tightened with the bolts 21. The attachment strength can be increased by increasing the attachment force to the fuel tank 20.

FIG. 2(a) shows a molding bag in which the filler tube 10 shown in FIG. 1 is blow-molded.

In this figure, reference numerals 40A and 40B denote a pair of molds (40
A is the left mold, and 40B is the right mold). Mold 40
A and 40B are moved by arrows A and B by a drive device (not shown).
It is designed to slide in the front-back direction, and first molding surfaces 41A and 41B that match the outer shape of the filler tube main body 12 to be molded are formed on the opposing surfaces. The lower end portions of the first molding surfaces 41A, 41B are connected to the first molding surfaces 41A, 41 via step portions 42A, 42B.
Second molding surfaces 43A and 43B deeper than B are formed, respectively, and the flange portion 14 is molded within these second molding surfaces 43A and 43B.

The opposing surfaces of the molds 40A and 40B each have a molding surface 41A.
, 41B surrounding the pinch-off portion 43A, 43B.
4A and 44B are provided in a protruding manner, and the supply parison 32 is pinched by sliding the molds 40A and 40B in the directions of arrows A and B.

Inside the molding surfaces 43A and 43B are cylinder mechanisms 50A and 50.
Lower molds 45A and 45B that can be slid vertically by B
(The lower left mold is designated as 45A, and the lower right mold is designated as 45B). Lower mold 45A.

As shown in FIG. 3, 45B has a substantially semi-cylindrical shape formed by vertically halving a cylindrical body, and molds 40A, 4. Recesses 46A, 46 having the same diameter as the molding surfaces 41A, 41B formed in the OB
B is formed.

In addition, the pinch-off portions 44A, 44B of the molds 40A, 40B are located along the outer periphery of the opposing surfaces of both the molds 45A, 45I3.
Pinch-off parts 47A and 47B which are flush with each other are provided in a protruding manner to pinch the supply parison 32 in cooperation with the pinch-off parts 44A and 44B.

The cylinder mechanism 50A (50B) is the mold 40A (40B).
) A pair of cylinders 52A (52B) and a telescopic rod 5 are mounted and fixed on both sides of the side wall (in the direction perpendicular to the plane of the paper in Fig. 2 (a)).
4A (54B), cylinder 5
2A (52B) is operated by telescopic rod 54A (54B).
) A horizontal pedestal 56 that supports the molds 45A and 45B via
A (56B) is designed to be slid in the vertical direction. As a result, the lower mold 45A (45B) has a molding surface 43
It slides up and down along A (43B). Lower mold 45A
, 45B cooperate to form one cylindrical lower mold 45 when the left and right molds 40A, 40B (7) pinch-off parts 44A, 44B are in close contact.

A total of four cylinders 52, including cylinder mechanisms 50A and 50B.
By interlocking A, 52A, 52B, and 52B,
The molding surfaces 43A and 43B slide together as one body. Note that reference numeral 34 is an air pipe that supplies air into the pinched parison.

Next, a procedure for blow molding the filler tube 10 according to this embodiment using the molding apparatus shown in FIG. 2(a) will be described.

First, as shown in FIG. 2(a), when a predetermined amount of parison 32 is supplied from the parison supply nozzle 30, the pair of molds 40A and 40B are moved closer to each other, and as shown in FIG.
), pinch the parison 32. Air is then supplied into the pinched parison 32 by the air vibrator 34. Then, as shown in FIG. 2(c), the parison 32 is formed on the molding surfaces 41A, 41B; 43 of the mold.
A, 43B and the inner peripheral surfaces of the recesses 46A, 46B of the lower mold 45 are pressed, and a bulging portion 32A is formed at the lower part of the parison 32. Next, as shown in FIG. 2(d), the lower mold 45 (4
5A and 45B) upward and step part 42
In cooperation with A and 42B, the bulging portion 32A of the parison 32 is pressed to form a thick flange portion 32B. This state is maintained until the parison 32 (resin molded body) in the mold is cooled and solidified. After the molding is completed, the molded body is taken out and the end portion is cut at the position indicated by the fourth cylinder number 36 to form the reference guide portion 13 at the lower end of the filler tube. Other finishing work such as deburring the windows is performed and the molding of the filler tube is completed.

In manufacturing the filler tube, the parison 32 supplied from the parison supply nozzle 30 is a so-called small-diameter parison that is smaller in shape than the molding surfaces 41A and 41B of the mold.
larger than the shape of.

A so-called large-diameter parison may be used, and in this case, when the left and right molds 40A and 40B are pinched, the state will be similar to that shown in FIG. 2(c).

Further, in the above-mentioned molding apparatus, recesses 46A and 46B are formed in the upper end surface, which is the press surface, of the lower mold 45 (45A, 45B) for press-molding the flange portion.
As shown in the figure, the upper end surface of the lower mold 45 may be made a flat surface, and in this case, a molded body with a flat lower surface of the flange portion 32B as shown in FIG. 6 can be obtained. In the molded body shown in FIG. 6, the portion indicated by reference numeral 38 may be cut and removed in a circular shape to form an opening in the center of the flange portion.

FIG. 7 shows another embodiment made by molding.

The molding apparatus shown in the above embodiment has an air pipe provided on the parison supply side, but in this embodiment, the air pipe is provided on the lower mold side in which the flange portion is press-molded.

In FIG. 7, the air pipe 34A is connected to the molding surface 41 of the mold.
A, 41B, and its tip outer peripheral surface is located at a distance equivalent to the thickness of the parison 32 from the molding surfaces 41A, 41B, and the lower mold 55 ( The lower left mold 55A and the lower right mold 55B) are capable of sliding movement in the vertical direction. The rest has the same structure as the blow molding apparatus described above, and is designated by the same reference numerals, so that detailed explanation thereof will be omitted.

The procedure for molding a filler tube using the molding apparatus shown in FIG.
After pinching with A and 40B, first, the lower mold 55 is slid upward as shown in FIG. 8 to press the flange portion 32B. Then, air is supplied through the air pipe 34A to perform blow molding. This point is different from the molding procedure using the molding apparatus shown in FIG. 2, in which the flange portion is press-formed after supplying air or while supplying air. The other molding procedures are the same as those using the molding apparatus shown in FIG. 2, and the explanation thereof will be omitted.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the flange portion that connects to the fuel tank is integrated with the tube body, and a sufficient thickness is ensured, so the filler tube has strong installation strength. is obtained, and a highly reliable connection structure between the filler tube and the fuel tank can be achieved by fastening the two with a large fastening force.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a filler tube according to an embodiment of the present invention, and FIG. 2(a) is a partial cross-sectional view of a molding device for molding a filler tube according to the first embodiment. 2(b) to 2(d) are explanatory diagrams explaining the operation of the molding device, FIG. 3 is a perspective view of the main parts of the molding device, and FIG. 4 is a molding process performed by the molding device. FIG. 5 is a longitudinal cross-sectional view of a main part of another embodiment of the molding apparatus, FIG. 6 is a cross-sectional view of a main part of a molded object molded by another molding apparatus, and FIG. FIG. 8 is a longitudinal sectional view showing another molding device, FIG. 8 is an explanatory view explaining its operation, and FIGS. 9 to 11 are explanatory views explaining the conventional filler tube manufacturing procedure. 10... Filler tube, 12... Tube body. 14...Flange part, 32...Parison, 34,3
4A...Air pipe, 40A...Left mold, 40B
...Right mold, 45.55...Lower mold, 45A, 55
A...lower left mold, 45B, 55B...lower right mold. Size OQ Tsuka Tsuka

Claims (1)

[Claims] (1) A synthetic resin filler tube which is a blow-molded body in which a flange portion for connection to a fuel tank is formed integrally with the tube body at one end of the filler tube body, and the flange portion is attached to the parison during blow molding. A synthetic resin filler tube characterized by being pressed by a press die that slides in the opposite direction to the supply direction to form a sufficiently thick walled portion compared to the tube body.