JP2015116901A - Connection structure of filler pipe and fuel tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure durability while ensuring the freedom of design of a fuel tank.SOLUTION: An inlet lower pipe 20 comprises an internal projection 20A projecting inside a tank body 18 and an external projection 20B projecting outside the tank body 18. One part of a connection member 16 in a longitudinal direction is a tank insertion part 22 to be inserted into the inlet lower pipe 20 in a fluid-tight manner, and the other part of the connection member 16 is a pipe connection part 24 to be connected to the filler pipe 14 in the fluid-tight manner. A non-return valve 34 is provided at a tip of the tank insertion part 22. When the tank insertion part 22 of the connection member 16 is connected to the inlet lower pipe 20 in the fluid-tight manner, a length (area) of a portion for supporting the tank insertion part 22 with the inlet lower pipe 20 is ensured, thereby suppressing a projection amount of the inlet lower pipe 20 to the outside of the fuel tank 10.

Description

  The present invention relates to a coupling structure between a filler pipe and a fuel tank.

A vehicle that uses an internal combustion engine as a drive source is equipped with a fuel tank that stores fuel, and the fuel tank is connected to a filler opening provided in the vehicle via a filler pipe.
In Patent Document 1 (FIG. 10), a cylindrical inlet lower pipe (valve mounting portion) that protrudes from the wall surface of the fuel tank to the outside of the fuel tank is provided as a coupling structure of the filler pipe and the fuel tank. A cylindrical housing constituting a check valve is inserted and attached to the inside of the pipe, and a portion of the housing exposed from the inlet lower pipe and a filler pipe (connection pipe) are attached. .

JP 2001-163069 A

However, in the above prior art, in order to simultaneously secure the mounting strength of the housing by the inlet lower pipe and the durability of the coupling structure of the filler pipe and the fuel tank, the length (area) of the portion where the inlet lower pipe supports the housing. It is necessary to ensure. Therefore, it is necessary to lengthen the inlet lower pipe protruding from the fuel tank.
On the other hand, when the fuel tank is configured by seam welding with the flange of the upper tank joined to the inlet lower pipe and the flange of the lower tank, the valve mounting part is closer to the flange of the upper tank. Often placed.
In this case, if the inlet lower pipe protruding from the fuel tank is lengthened, the roller electrode for seam welding may interfere with the inlet lower pipe, so the inlet lower pipe must be laid out so as not to interfere with the roller electrode. There is a disadvantage that the degree of freedom in designing the fuel tank is limited.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a filler pipe-fuel tank coupling structure that is advantageous in ensuring the degree of freedom in designing the fuel tank while ensuring durability. Is to provide.

In order to achieve the above object, the invention according to claim 1 is a filler pipe connected to a fuel filler port and located upstream of a fuel pipe, and an inlet lower pipe connected to a fuel tank and located downstream of the fuel pipe. And a fuel piping structure of a fuel tank having a coupling member for coupling the filler pipe and the inlet lower pipe, wherein the inlet lower pipe is provided penetrating from the outside to the inside of the fuel tank, The coupling member is formed in a cylindrical shape, the downstream end is inserted into the inlet lower pipe and disposed inside the fuel tank, and the upstream end is connected to the filler pipe outside the fuel tank. It is characterized by.
According to a second aspect of the present invention, an enlarged diameter portion is formed at an upstream end portion of the fuel pipe of the inlet lower pipe, and the coupling member and the inlet lower pipe are coupled at a location of the enlarged diameter portion. A sealing member is provided between the inner peripheral surface of the inlet lower pipe and the outer peripheral surface of the coupling member on the downstream side of the fuel pipe from the enlarged diameter portion.
According to a third aspect of the present invention, the inlet lower pipe and the coupling member are engaged with an inner peripheral surface of the inlet lower pipe on a downstream side of the fuel pipe from a position where the seal member of the coupling member is disposed. And an alignment portion for coaxially aligning with each other.
According to a fourth aspect of the present invention, the downstream end of the inlet lower pipe is disposed further downstream than the downstream end of the coupling member, and the downstream end of the coupling member includes A valve for restricting the inflow of fuel from the fuel tank to the fuel pipe is provided.

According to the first aspect of the present invention, since the portion where the inlet lower pipe and the coupling member are doubled is arranged from the outside to the inside of the fuel tank, the strength of the connection portion between the inlet lower pipe and the coupling member is increased. Can be improved. Furthermore, even if the part where the inlet lower pipe protrudes outside the fuel tank is shortened, the entire length of the inlet lower pipe can be secured by lengthening the part protruding inside the fuel tank. The length (area) of the portion that supports the member can be ensured.
Therefore, while ensuring the durability of the coupling structure between the filler pipe and the fuel tank, the amount of protrusion of the portion where the inlet lower pipe protrudes to the outside of the fuel tank can be suppressed, and the degree of freedom in designing the fuel tank is ensured. This is advantageous.
According to invention of Claim 2, it is comprised so that the internal diameter of the upstream edge part of an inlet lower pipe may become larger than the outer diameter of a coupling member by providing an enlarged diameter part. Thereby, a coupling member can be inserted in an inlet lower pipe, without touching the front-end | tip of an inlet lower pipe. In other words, when the tank insertion portion is inserted into the inlet lower pipe, the seal member sandwiched between the inlet lower pipe and the coupling member is prevented from coming into contact with the tip burr or edge of the inlet lower pipe and being damaged. This is advantageous, and the liquid tightness between the inlet lower pipe and the coupling member can be improved.
According to the third aspect of the present invention, after the tank insertion portion and the inlet lower pipe are aligned coaxially by the alignment portion, the seal member is inserted into the enlarged diameter portion. Therefore, it is more advantageous to prevent the seal member from coming into contact with the tip burr or edge of the inlet lower pipe and damaging it.
According to the fourth aspect of the invention, since the valve is surrounded by the inlet lower pipe because the tip of the coupling member is located closer to the inside of the fuel tank, the fuel flowing in the fuel tank is directly applied to the valve. Therefore, it is advantageous to smoothly introduce fuel into the fuel tank during refueling.

It is a figure which shows the whole structure of the oil supply apparatus with which the joint structure of the filler pipe and fuel tank in embodiment was applied. It is an expanded sectional view of the joint structure of the filler pipe and fuel tank in an embodiment. (A) is a side view of a coupling member, (B) is a B arrow view of (A), (C) is a CC line sectional view of (A). It is a disassembled sectional view of the coupling structure of the filler pipe and the fuel tank in the embodiment.

Next, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the vehicle is provided with a fuel supply device 2 that supplies fuel F to a fuel tank 10, and the present invention is applied to the fuel supply device 2.
The oil supply device 2 includes an inlet filler pipe 12, a filler pipe 14, and a coupling member 16 described later.
One end in the length direction of the inlet filler pipe 12 is attached to the opening of the outer plate of the vehicle via an attachment member, and one end in the length direction serves as a fuel filler opening 1202 that is opened and closed by the cap 13. Yes.
The filler pipe 14 is made of a synthetic resin having excellent fuel F impermeability.
The filler pipe 14 has flexibility, one end in the length direction of the filler pipe 14 is liquid-tightly coupled to the other end in the length direction of the inlet filler pipe 12, and the other end in the length direction is a coupling member. The fuel tank 10 is liquid-tightly coupled to the fuel tank 10 via 16.
In the present embodiment, a fuel pipe for supplying fuel from the fuel filler opening 1202 to the fuel tank 10 is constituted by the inlet filler pipe 12, the filler pipe 14, the coupling member 16, and the inlet lower pipe 20 of the fuel tank 10 described later. Has been.
Therefore, the inlet filler pipe 12 is located on the upstream side of the fuel piping, and the inlet lower pipe 20 is located on the downstream side of the fuel piping. In other words, the inlet filler pipe 12 constitutes the upstream portion of the fuel piping, The inlet lower pipe 20 constitutes a downstream portion of the fuel pipe.

Next, the fuel tank 10 will be described.
The fuel tank 10 includes a tank body 18 and an inlet lower pipe 20.
The tank body 18 is configured by welding a metal lower tank 18A and a metal upper tank 18B.
The lower tank 18A includes a bottom wall 1802, a side wall 1804 that rises upward from the periphery of the bottom wall 1802, and a flange 1806 that protrudes from the upper end of the side wall 1804 to the outside of the side wall 1804 over the entire periphery.
The upper tank 18B includes an upper wall 1812 facing the bottom wall 1802, a side wall 1814 standing downward from the periphery of the upper wall 1812, and a flange protruding from the lower end of the side wall 1814 to the outside of the side wall 1814 over the entire periphery. 1816.
The flange 1806 of the lower tank 18A and the flange 1816 of the upper tank 18B are joined in a superposed state. This joining is performed by seam welding by energizing in a state of being sandwiched between upper and lower roller electrodes.

As shown in FIG. 2, the inlet lower pipe 20 is made of metal and has a cylindrical shape, and is joined to the side wall 1814 of the upper tank 18B in a state of passing through an opening provided in the side wall 1814 of the upper tank 18B. That is, the inlet lower pipe 20 is provided so as to penetrate from the outside to the inside of the fuel tank 10.
The inlet lower pipe 20 has an internal protrusion 20 </ b> A that protrudes into the tank body 18 and an external protrusion 20 </ b> B that protrudes outside the tank body 18.
The inner diameter portion of the inlet lower pipe 20 has a smaller diameter portion 2002 formed with a uniform inner diameter from the tip of the inner protrusion portion 20A to the outer protrusion portion 20B, and an inner diameter larger than the smaller diameter portion 2002 provided at the end portion of the outer protrusion portion 20B. And an enlarged diameter portion 2004. In other words, the enlarged diameter portion 2004 is formed at the upstream end of the fuel piping of the inlet lower pipe 20.
The small-diameter portion 2002 and the enlarged-diameter portion 2004 are connected by an inclined surface 2006 where the inner diameter gradually decreases from the enlarged-diameter portion 2004 to the small-diameter portion 2002. The inclined surface 2006 may be formed as a conical surface or a curved surface.
In the present embodiment, the inlet lower pipe 20 is joined to the side wall 1814 of the upper tank 18B by welding the location of the outer peripheral surface of the small diameter portion 2002 and the location of the side wall 1814 around the opening. At this time, the location to be welded on the inlet lower pipe 20 side is preferably a connection position between the outer peripheral surface of the small diameter portion 2002 and the inclined portion 2006. Thereby, while ensuring the durability of the coupling structure of the filler pipe 14 and the fuel tank 10, it is possible to further suppress the protruding amount of the external protruding portion 20 </ b> B to the outside of the fuel tank 10, and to design the fuel tank 10. This is advantageous in securing the degree of freedom. Further, since the coupling member 16 can be inserted further into the fuel tank 10, the total length of the coupling member 16 can be shortened, so that assembly is facilitated and cost can be reduced.
As shown in FIGS. 2 and 4, the enlarged diameter portion 2004 is formed with three engagement holes 2010 penetrating in the radial direction at equal intervals in the circumferential direction.
The fuel tank 10 is dried in a high temperature environment after its outer surface is painted.

Next, the coupling member 16 will be described.
As shown in FIG. 2, the coupling member 16 is made of synthetic resin, and couples the filler pipe 14 and the inlet lower pipe 20.
The coupling member 16 is cylindrical and has an elongated shape, and a space portion S for fuel passage is formed through the longitudinal direction thereof. As shown in FIGS. 3 (A), (B), (C), and FIG. The insertion portion 22, the pipe coupling portion 24, the seal member 26, the stopper 28, the engagement claw 30, the alignment portion 32, and the check valve 34 are configured.

The tank insertion portion 22 is configured by one portion of the coupling member 16 in the longitudinal direction, and is inserted into the inlet lower pipe 20 in a liquid-tight manner.
In the present embodiment, as shown in FIG. 2, the tank insertion portion 22 is connected to the inlet lower pipe 20 in a liquid-tight state, and the tip thereof is the wall surface of the fuel tank 10 through which the inlet lower pipe 20 passes. It is provided so that it may be located inside the fuel tank 10 relative to Thereby, while the length (area) of the part which the inlet lower pipe 20 supports the tank insertion part 22 is ensured, the protrusion amount of the external protrusion part 20B to the outward of the fuel tank 10 is suppressed.
In other words, the downstream end portion of the fuel pipe of the inlet lower pipe 20 is disposed further downstream than the downstream end portion of the fuel pipe of the coupling member 16.

The pipe coupling portion 24 is configured by the other portion in the longitudinal direction of the coupling member 16 and is liquid-tightly coupled to the filler pipe 14.
In the present embodiment, as shown in FIG. 4, a plurality of convex portions 2402 and concave portions 2404 formed along the circumferential direction are repeatedly formed on the outer peripheral surface of the pipe coupling portion 24 in the longitudinal direction. 14 is secured.

As shown in FIG. 4, the seal member 26 is attached to the tank insertion portion 22 and is in fluid-tight contact with the inner peripheral surface of the small diameter portion 2002. In this embodiment, the outer peripheral surface of the tank insertion portion 22 is used. It is comprised with the O-ring with which the groove part 2202 formed in this was mounted | worn.
That is, the seal member 26 is sandwiched between the inner peripheral surface of the inlet lower pipe 20 and the outer peripheral surface of the coupling member 16 on the downstream side of the fuel pipe from the enlarged diameter portion 2004.

  As shown in FIGS. 2 and 4, when the tank insertion portion 22 is inserted into the inlet lower pipe 20, the stopper 28 is brought into contact with the tip of the external protrusion 20B of the inlet lower pipe 20, thereby The insertion position is regulated.

As shown in FIGS. 3B and 4, three engaging claws 30 are provided at equal intervals in the circumferential direction of the coupling member 16 between the tank insertion portion 22 and the pipe coupling portion 24. By engaging with each engagement hole 2010 of the diameter portion 2004, an engagement portion that prevents the movement of the coupling member 16 in the axial direction of the inlet lower pipe 20 is configured.
That is, the coupling member 16 and the inlet lower pipe 20 are coupled at the enlarged diameter portion 2004 by the engaging portion.

The alignment part 32 aligns the inlet lower pipe 20 and the tank insertion part 22 on the same axis.
The alignment unit 32 includes a plurality of claw portions 32 </ b> A and is provided in the tank insertion unit 22.
As shown in FIGS. 3A, 3 </ b> B, and 3 </ b> C, the plurality of claw portions 32 </ b> A are arranged more radially than the outer peripheral surface of the tank insertion portion 22 on the distal end side of the tank insertion portion 22 with respect to the seal member 26. It protrudes outward and is provided so as to be elastically deformable radially inward by the inner peripheral surface of the small diameter portion 2002 of the inlet lower pipe 20.
In the present embodiment, the outer surface of the claw portion 32A is formed by a tapered surface 3202 that gradually inclines radially outward toward the pipe coupling portion 24, and the claw portion 32A is the inner periphery of the small diameter portion 2002 of the inlet lower pipe 20 It is designed to be easily inserted into the surface.
Further, the claw portion 32A is surrounded by a groove portion 2210 formed in the radial direction of the tank insertion portion 22 except for the base end portion connected to the tank insertion portion 22, and the claw portion 32A is elastically deformed. It is designed to be easy.
In the present embodiment, three claw portions 32 </ b> A are provided at equal intervals in the circumferential direction of the outer peripheral surface of the tank insertion portion 22. Two or four or more claw portions 32A may be provided.
And the distance of the sealing member 26 and the alignment part 32 along the longitudinal direction of the tank insertion part 22 is formed in the dimension larger than the length of the enlarged diameter part 2004 along the longitudinal direction of the external protrusion part 20B. . As a result, when the coupling member 16 is inserted into the fuel tank 10, the inlet lower pipe 20 and the tank insertion portion 22 are coaxially aligned, and then the seal member 26 is inserted into the enlarged diameter portion 2004. It has been.

The check valve 34 prevents back flow of the fuel F, and is provided at the tip of the tank insertion portion 22. In other words, a valve 34 that restricts the inflow of the fuel F from the fuel tank 10 to the fuel pipe is provided at the tip of the tank insertion portion 22.
In the present embodiment, as shown in FIGS. 3B and 4, the check valve 34 includes a valve body 3402 that is swingably attached to the tank insertion portion 22 and opens and closes an opening, and a valve body 3402. And a torsion spring 3404 that biases the opening in a closing direction.
In the present embodiment, as shown in FIG. 2, the check valve 34 includes, in the longitudinal direction of the inlet lower pipe 20, the tip of the internal protrusion 20 </ b> A and the location of the wall surface of the fuel tank 10 through which the inlet lower pipe 20 passes. Is located between. In other words, the check valve 34 is provided at the downstream end of the fuel pipe of the coupling member 16.
Accordingly, since the check valve 34 is surrounded by the inlet lower pipe 20, the fuel F flowing in the fuel tank 10 is directly applied to the check valve 34, so that the check valve 34 is damaged and cannot be opened. Therefore, it is advantageous to smoothly introduce the fuel F into the fuel tank 10 during refueling.

Next, a procedure for joining the filler pipe 14 and the inlet lower pipe 20 will be described.
First, the coupling member 16 is liquid-tightly coupled to the filler pipe 14 by press-fitting the pipe coupling portion 24 of the coupling member 16 into the end portion of the filler pipe 14.
Next, a painted fuel tank 10 is prepared, and the tip of the tank insertion portion 22 of the coupling member 16 is inserted into the inlet lower pipe 20 joined to the fuel tank 10.
By inserting the coupling member 16, each claw portion 32 </ b> A is pressed by the inner peripheral surface of the small diameter portion 2002 of the inlet lower pipe 20 and displaced radially inward, so that the coupling member 16 is aligned with the inlet lower pipe 20. That is, they are aligned so as to be located on the same axis.
By further insertion of the coupling member 16, the seal member 26 is inserted into the small diameter portion 2002 through the enlarged diameter portion 2004, and the seal member 26 is elastically contacted with the inner peripheral surface of the small diameter portion 2002 in a liquid-tight manner.
With the further insertion of the coupling member 16, the stopper 28 comes into contact with the tip of the external protrusion 20 </ b> B of the inlet lower pipe 20. Therefore, the coupling member 16 is rotated in the circumferential direction so that the engagement claws 30 are engaged with the engagement holes 2010 of the enlarged diameter portion 2004.
As a result, the coupling member 16 is liquid-tightly coupled to the inlet lower pipe 20.

According to the present embodiment, the inlet lower pipe 20 has an internal protrusion 20A that protrudes into the fuel tank 10 and an external protrusion 20B that protrudes out of the fuel tank 10.
Therefore, even if the length of the external protrusion 20B of the inlet lower pipe 20 is shortened, the entire length of the inlet lower pipe 20 can be ensured by increasing the length of the internal protrusion 20A.
Thereby, when the tank insertion part 22 of the coupling member 16 is liquid-tightly connected to the inlet lower pipe 20, the length (area) of the part where the inlet lower pipe 20 supports the tank insertion part 22 can be secured. .
Therefore, it is advantageous in securing the mounting strength of the coupling member 16 by the inlet lower pipe 20. In addition, since the amount of protrusion of the inlet lower pipe 20 to the outside of the fuel tank 10 can be suppressed, the roller electrode for performing seam welding is less likely to interfere with the inlet lower pipe 20 and the inlet lower pipe 20 so as not to interfere with the roller electrode. No need to lay out.
Therefore, it is advantageous in securing the degree of freedom in designing the fuel tank 10 while ensuring the durability of the coupling structure of the filler pipe 14 and the fuel tank 10.

Further, in the present embodiment, the tank insertion portion 22 of the coupling member 16 is liquid-tightly inserted into the inlet lower pipe 20 to ensure the sealing performance between the coupling member 16 and the inlet lower pipe 20.
Since the inner peripheral surface of the inlet lower pipe 20 into which the coupling member 16 is inserted in a liquid-tight manner is not exposed to the outside, the inner peripheral surface of the inlet lower pipe 20 is not easily damaged and is managed so that dust does not adhere to it. All you need is enough.
On the other hand, when the coupling member 16 is coupled to the outer peripheral surface of the inlet lower pipe 20, the seal between the coupling member 16 and the inlet lower pipe 20 is caused by scratches on the outer peripheral surface of the inlet lower pipe 20 or unevenness of the coating on the fuel tank 10. Sexuality is easily lost.
Therefore, in the case of such a structure, a protective cap must be attached so that the outer peripheral surface of the inlet lower pipe 20 is not damaged, and a portion of the outer peripheral surface of the inlet lower pipe 20 that is not coated is masked. It takes time and effort and the manufacturing process becomes complicated.
On the other hand, this embodiment is advantageous in simplifying the manufacturing process because it does not take time and labor to attach / detach such a protective cap and masking work.

Further, when the seal member 26 passes through the enlarged diameter portion 2004 of the inlet lower pipe 20, the enlarged diameter portion 2004 has a larger diameter than the small diameter portion 2002, so that the seal member 26 and the edge of the enlarged diameter portion 2004 are A space can be secured between them. Therefore, it is advantageous in preventing the seal member 26 from being damaged by coming into contact with burrs or edges at the edge of the enlarged diameter portion 2004. By preventing the seal member 26 from being damaged, it is advantageous in securing the sealing performance between the coupling member 16 and the inlet lower pipe 20.
The enlarged diameter portion 2004 only needs to have an inner diameter larger than that of the smaller diameter portion 2002 to the extent that damage to the seal member 26 can be prevented, and the accuracy of the shape and size of the enlarged diameter portion 2004 is not so necessary. Therefore, the enlarged diameter portion 2004 that prevents damage to the seal member 26 is easily processed, which is advantageous in simplifying the manufacturing process of the inlet lower pipe 20.

  In addition, since the alignment portion 32 is provided, when the seal member 26 passes through the enlarged diameter portion 2004, a space can be ensured between the seal member 26 and the edge of the enlarged diameter portion 2004 more reliably. Therefore, it is further advantageous to prevent the seal member 26 from coming into contact with the edge burr or edge of the enlarged diameter portion 2004 and being damaged, and to ensure the sealing performance between the coupling member 16 and the inlet lower pipe 20. Is even more advantageous.

DESCRIPTION OF SYMBOLS 10 Fuel tank 12 Inlet filler pipe 1202 Filler port 14 Filler pipe 16 Connection member 20 Inlet lower pipe 20A Inner protrusion part 20B Outer protrusion part 2002 Small diameter part 2004 Large diameter part 2010 Engagement hole 22 Tank insertion part 24 Pipe joint part 26 Seal member 30 Engaging Claw 32 Positioning Section 34 Check Valve (Valve)

Claims (4)

A filler pipe connected to the fuel filler port and located upstream of the fuel pipe, an inlet lower pipe connected to a fuel tank and located downstream of the fuel pipe, and a coupling member for joining the filler pipe and the inlet lower pipe A fuel pipe structure of a fuel tank having
The inlet lower pipe is provided penetrating from the outside to the inside of the fuel tank,
The coupling member is formed in a cylindrical shape, the downstream end is inserted into the inlet lower pipe and disposed inside the fuel tank, and the upstream end is connected to the filler pipe outside the fuel tank. The filler pipe and fuel tank connection structure. An enlarged diameter portion is formed at the upstream end of the fuel pipe of the inlet lower pipe,
The coupling member and the inlet lower pipe are coupled at the enlarged diameter portion,
A seal member is provided that is sandwiched between the inner peripheral surface of the inlet lower pipe and the outer peripheral surface of the coupling member on the downstream side of the fuel pipe from the enlarged diameter portion.
The combined structure of a filler pipe and a fuel tank according to claim 1. Positioning of the coupling member that is engaged with the inner peripheral surface of the inlet lower pipe and coaxially aligns the inlet lower pipe and the coupling member on the downstream side of the fuel pipe with respect to the location where the seal member is disposed. Part is provided,
The combined structure of a filler pipe and a fuel tank according to claim 2. The downstream end of the inlet lower pipe is disposed further downstream than the downstream end of the coupling member,
The filler pipe according to any one of claims 1 to 3, wherein a valve that regulates inflow of fuel from the fuel tank to the fuel pipe is provided at the downstream end of the coupling member. Connection structure with fuel tank.

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