JP2006224991A - Connecting part attaching structure in fuel tank made of synthetic resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting part attaching structure which has a large resisting force to heat from outside and a force in the rotational direction and which can prevent the leakage of a fuel or the dropping of a connecting part from occurring. <P>SOLUTION: A drain sheet 4 is attached to a connecting part attaching section 3 of the fuel tank 2 made of the synthetic resin by insert-molding. In this case, for the drain sheet 4, a plurality of flanges 6 and 7 facing outward are provided on a cylindrical section 5 while separating them in the axial direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a connecting part mounting structure in a synthetic resin fuel tank such as an automobile or a boiler.

A drain sheet, which is a metal connection part with an outward flange on the cylinder part, is attached to the bottom of a synthetic resin fuel tank by insert molding, and a drain plug is screwed into this connection part ( For example, see Patent Document 1)
Utility Model Registration No. 2541418

Since the connecting part described in Patent Document 1 has only one outward flange formed on the cylinder part, when receiving heat from a flame or the like from the outside of the tank, the connecting part mounting part of the tank The resin melts, and a gap is generated between the connection component and the connection component mounting portion, which may cause fuel leakage or, in the worst case, the connection component may fall out of the tank.
Also, since the drag force against the external force in the rotation direction is not sufficient, when screwing the drain plug into the connection component, if overtorque is applied to the drain plug, a gap may occur between the connection component and the connection component mounting portion. Even in such a case, there is a problem that it is difficult to prevent fuel leakage with only one outward flange.

  In view of the above-mentioned problems of the prior art, the present invention has a large resistance to external heat and rotational force, and is capable of preventing fuel leakage and connection parts from falling off. Its purpose is to provide a structure.

According to the present invention, the above problem is solved as follows.
(1) A connecting part provided with a plurality of outward flanges separated from each other in the axial direction is attached to the connecting part attaching part of the synthetic resin fuel tank by insert molding.

(2) In the above item (1), the outer shape of the outward flange is made non-circular so that the connecting part is prevented from rotating around the tank.

(3) In the above item (2), unevenness for rotation prevention is provided on the surface of the outward flange.

(4) In any one of the above items (1) to (3), the outward flange is provided with a through hole facing in the axial direction, and the synthetic resin material of the tank is filled in the through hole.

(5) In any one of the above items (1) to (4), the synthetic resin injection molded body into which the connection component is inserted is inserted into the connection component mounting portion during blow molding of the synthetic resin fuel tank, Install in the tank.

(6) In the above item (5), the material of the tank and the material of the injection molded body are the same or a synthetic resin material having strong affinity.

(7) In any one of the above items (1) to (4), a recessed part is provided in the connecting part mounting portion of the synthetic resin fuel tank, the connecting part is inserted into the recessed part, and other than the connecting part in the recessed part This portion is filled with a synthetic resin material having the same or strong affinity as the material of the tank, and the connection component is attached to the connection component attachment portion of the tank.

(8) In any one of the above items (1) to (7), the connecting component is a drain sheet and is provided on the bottom or side of the tank.

According to the present invention, the following effects can be achieved.
(A) According to the invention of claim 1, by providing a plurality of outward flanges spaced apart in the axial direction in the cylindrical portion, even if the resin of the connecting part mounting portion is melted by heat from the outside of the tank, As long as the resin between the plurality of outward flanges does not melt, the connecting parts do not fall off.
In addition, the use of multiple outward flanges not only increases the contact area between the resin of the mounting part and the connection parts, increases the peel strength, but also overloads the plugs that are screwed into the connection parts. Even if there is a slight gap between the two, the fuel leaks because the resin exists between the multiple outward flanges even if the contact part between the resin of the mounting part and the connecting part is peeled off and a gap is generated between them. Can be prevented.

(B) According to the invention described in claim 2, since the outer shape of the outward flange is a non-circular shape, the connection component can be strongly prevented from rotating around the tank.

(c) According to the invention described in claim 3, since the unevenness for rotation prevention is provided on the surface of the outward flange, the connection component can be strongly prevented from rotating on the tank.

(d) According to the invention described in claim 4, since the through-hole facing in the axial direction is provided in the outward flange, and the synthetic resin material of the tank is filled in the through-hole, the inside of the through-hole is filled. Due to the synthetic resin material of the tank, the connecting parts are strongly prevented from rotating in the tank.

(e) According to the invention of claim 5, since the injection molded body in which the connection part is insert-molded is inserted into the connection part mounting part at the time of blow molding of the fuel tank, the resin in the injection molded body and the connection part mounting part is melted together. In addition, since the injection molding material has a large melt flow rate, even when the connection component is made of metal, a connection component mounting structure with high adhesion to the connection component and high bonding strength can be obtained.

(f) According to the invention described in claim 6, since the material of the tank and the material of the injection-molded body are the same or a strong synthetic resin material, the bond strength between the tank and the injection-molded body is increased. .

(g) According to the invention described in claim 7, after inserting the connection component into the recess provided in the connection component mounting portion, the portion other than the connection component in the recess has the same or strong affinity with the material of the tank. Since the synthetic resin material is filled, the connecting component and the filling resin are fixed, and at the same time, the resin and the filling resin of the connecting component mounting portion are melted and welded together to obtain a high strength connecting component mounting structure. .

(h) According to the invention of claim 8, the drain sheet has a high peel strength and is less likely to drop off. In the unlikely event, the drain plug screwed into the drain sheet is fastened with over torque, Even if the contact part with the drain sheet peels off and there is some gap between them, the resin exists between the multiple outward flanges, so the synthetic resin can prevent the fuel from leaking A structure for attaching a drain sheet to a fuel tank can be provided.

Embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a longitudinal front view of a bottom portion of a synthetic resin fuel tank provided with a first embodiment of the present invention, and FIG. 2 is a cross-sectional plan view taken along line II-II in FIG.

  A thick connecting component mounting portion (3) is provided at a part of the bottom of a synthetic resin fuel tank (hereinafter simply referred to as a tank) (2) containing fuel (1). ), A drain sheet (4) which is a connecting part is attached by insert molding.

  The drain sheet (4) is made of a metal material, and a plurality of, in the illustrated example, two outward flanges (6) and (7) are arranged in the axial direction of the cylinder part (5) on the outer periphery of the cylinder part (5). They are separated from each other. A female screw (8) is engraved on the inner periphery of the cylindrical portion (5) of the drain sheet (4), and a male screw (10) engraved on the outer periphery of the drain plug (9) is provided on the female screw (8). The drain is closed by screwing.

As shown in FIG. 2, the outward flanges (6) and (7) have a substantially circular shape, and are provided with unevenness (11) for preventing rotation on the outer periphery by knurling or the like. Similar irregularities may be provided on the other surfaces of the outward flanges (6) and (7).
The outward flanges (6) and (7) may be oval, quadrangular, polygonal or other non-circular shape. In such a case, it is not necessary to provide unevenness on the outer periphery to prevent rotation.

FIG. 3 shows a modification of the first embodiment.
In this example, an annular groove (12) is provided on the outer periphery of the cylindrical portion (5) above the upper outward flange (6), and an O-ring (13) is attached to the annular groove (12). . As a result, even if the drain sheet (4) rotates due to overtorque and a gap is formed between the resin of the connecting part mounting portion (3) and the drain sheet (4), the O-ring (13) Fuel leakage is prevented.

FIG. 4 is a longitudinal front view of a bottom portion of a synthetic resin fuel tank provided with the second embodiment of the present invention, and FIG. 5 is a cross-sectional plan view taken along the line VV in FIG.
In this example, the drain sheet (4) is insert-molded into an injection-molded body (14) made of a synthetic resin that is the same as the synthetic resin material of the tank (2) or has a strong affinity. The molded body (14) is inserted into the connecting part mounting portion (3) and attached to the tank (2) during blow molding of the synthetic resin fuel tank (2).
The synthetic resin material of the tank (2) is, for example, high-density polyethylene, and the synthetic resin material of the injection-molded body (14) is, for example, the same high-density polyethylene as described above or polypropylene having good affinity with it. Is good.

  Since the injection molding material usually has a high melt flow rate (MFR), it can be easily filled around the drain sheet (4) which is a metal product. The injection molded body (14) of the drain sheet (4) is insert-molded in a blow-molded tank (2), so that the resin materials are melted and integrally welded.

  As shown in FIG. 5, the contour of the injection molded body (14) is non-circular (the one shown is a hexagon), so that the injection molded body (14) is prevented from rotating at the connecting part mounting portion (3). The function of can be fulfilled. Note that the outward flanges (6) and (7) are circular with irregularities (11) on the outer periphery, but they may be non-circular.

  While the embodiments of the present invention have been described above, various modifications and changes can be made to the above embodiments without departing from the scope of the claims of the present invention.

  For example, in the second embodiment, the injection molded body (14) in which the drain sheet (4) is insert-molded is inserted into the connecting part mounting portion (3) during blow molding of the tank (2). The connecting part mounting part (3) of the tank (2) is provided with a recess in advance, the drain sheet (4) is inserted into the recess, and the material of the tank (2) is provided in a part other than the drain sheet (4) in the recess. It is also possible to fill the drain sheet (4) to the connecting part mounting portion (3) of the tank (2) by filling the same or a strong synthetic resin material.

  Also, the outward flanges (6) and (7) are provided with through holes (not shown) facing in the axial direction. The through holes are filled with the synthetic resin material of the tank (2) or the drain sheet (4). May be provided on the side of the tank (2).

It is a vertical front view of the bottom part of the synthetic resin fuel tank provided with the 1st Embodiment of this invention. Similarly, it is the II-II line transverse plane view of FIG. It is a vertical front view of the part similar to FIG. 1 which shows the modification of 1st Embodiment. It is a vertical front view of the part similar to FIG. 1 which shows the 2nd Embodiment of this invention. Similarly, it is a VV line transverse plane of FIG.

Explanation of symbols

(1) Fuel
(2) Synthetic resin fuel tank
(3) Connection part mounting part
(4) Drain sheet
(5) Tube part
(6) outward flange
(7) outward flange
(8) Female thread
(9) Drain plug
(10) Male thread
(11) Concavity and convexity
(12) Annular groove
(13) O-ring
(14) Injection molding

Claims (8)

  Connection in a synthetic resin fuel tank, characterized in that a connecting part provided with a plurality of outward flanges separated from each other in the axial direction is attached to the connecting part mounting part of the synthetic resin fuel tank by insert molding Part mounting structure.   The connecting part mounting structure in a synthetic resin fuel tank according to claim 1, wherein the connecting part is prevented from rotating around the tank by making the outer shape of the outward flange non-circular.   The connecting part mounting structure in a synthetic resin fuel tank according to claim 1 or 2, wherein the surface of the outward flange is provided with unevenness for rotation prevention.   The connecting part mounting structure in a synthetic resin fuel tank according to any one of claims 1 to 3, wherein a through hole facing the axial direction is provided in the outward flange, and the synthetic resin material of the tank is filled in the through hole. .   The synthetic resin injection-molded body into which the connecting part is inserted is inserted into the connecting part attaching portion at the time of blow molding of the synthetic resin fuel tank, and attached to the tank. The connecting part mounting structure in the synthetic resin fuel tank described in 1.   6. The connecting part mounting structure in a synthetic resin fuel tank according to claim 5, wherein the material of the tank and the material of the injection molded body are the same or a synthetic resin material having strong affinity.   A synthetic resin fuel tank connecting part mounting part is provided with a recess, and the connecting part is inserted into the recessed part, and the part other than the connecting part in the recess has the same or strong affinity as the material of the tank. 5. A connecting part mounting structure in a synthetic resin fuel tank according to claim 1, wherein a resin material is filled and the connecting part is attached to a connecting part mounting portion of the tank. The connecting part mounting structure in a synthetic resin fuel tank according to any one of claims 1 to 7, wherein the connecting part is a drain sheet and is provided at a bottom part or a side part of the tank.

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