JP2001191802A - Fuel inlet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel inlet capable of absorbing an assembling error and preventing the permeation of the fuel more strictly in comparison with the conventional one, while keeping the cost low. SOLUTION: This fuel inlet 10 is provided with a tank joint part 11, a fuel filling part 12, and a bellows part 13. Respective parts 11, 12, 13 are formed on one stainless steel pipe. Since this fuel inlet 10 is integrally formed with the metal bellows part 13 having the equal function to a rubber hose, assembling error can be absorbed while keeping the cost thereof lower than that of a rubber hose, and furthermore, permeation of the fuel can be prevented more strictly in comparison with the conventional one. Since the tank joint part 11 is integrally formed with the fuel inlet, besides the fuel filling part 12 and the bellows part 13, cost is lowered in comparison with a case of separately forming the tank joint part 11, and the fuel inlet 10 can be handled as a module.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel inlet used for supplying fuel to a fuel tank of an automobile.

[0002]

2. Description of the Related Art When fuel is injected into a fuel tank of an automobile, a fuel inlet 101 as shown in FIG. 8 is used. The fuel inlet 101 includes a fuel inlet main body 103 having a large-diameter fuel injection portion 102 into which a refueling nozzle is inserted, a tank connecting pipe 104 connected around an opening of the fuel tank 50, and a fuel connecting tank 103 with the fuel inlet main body 103. And a rubber hose 105 for connecting the tube 104.

[0003] A fuel injection portion 102 of the fuel inlet 101 is provided with a breather tube 106 communicating with the fuel tank 50, and a spiral for screwing a lid for closing the fuel injection portion 102 except during refueling. Groove 10
2a is provided. Then, at the time of refueling, the refueling nozzle is inserted into the fuel injection unit 102 to perform refueling. Then, the fuel is supplied to the fuel tank 5 through the fuel inlet main body 103, the rubber hose 105, and the tank connecting pipe 104.
It is led to 0. When the fuel is started to be supplied to the fuel tank 50, the air in the fuel tank 50 is released from the breather tube 10.
6 and is pushed out to the fuel injection part 102 side. When the fuel is continuously supplied, the fuel finally overflows from the opening of the breather tube 106 on the side of the fuel injection section 102. The fueler confirms this and ends the fueling work.

[0004]

However, in the fuel inlet 101, the rubber hose 105 is used to absorb an error at the time of assembling. However, since the unit price of the rubber hose 105 is high, the overall price is increased. There was a compelling problem. Further, although the rubber hose 105 is sufficiently designed so that fuel does not permeate, there is a demand that this point should be further enhanced.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and demands, and to provide a fuel inlet which can absorb errors at the time of assembling while being inexpensive and can further prevent fuel permeation as compared with the prior art. The purpose is to do.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a fuel inlet used for supplying fuel to a fuel tank of an automobile, which is joined around an opening of the fuel tank. The fuel injection portion, which is formed to have a larger diameter at the end opposite to the other side than the other portion and into which the refueling nozzle is inserted, and the end joined to the opening of the fuel tank and the opposite end And a bellows portion provided between the end portions of the metal pipe. Each of the portions is formed by molding one metal pipe.

In the fuel inlet of the present invention, since one metal pipe is formed and formed to form the fuel injection portion and the bellows portion, the bellows portion is made of metal. The metal bellows has a function similar to that of a conventional rubber hose, that is, a function of absorbing an error during assembly due to flexibility. In other words, according to the fuel inlet of the present invention, since the metal bellows portion is integrally formed, it is possible to absorb the error at the time of assembling at a lower price than the rubber hose, and to further prevent fuel permeation as compared with the conventional case. Is obtained.

[0008] In the fuel inlet of the present invention,
A tank joint may be provided at an end on the side joined to the periphery of the opening of the fuel tank, and this tank joint may be formed when one metal pipe is formed. For example, it is conceivable to separate the tank joint, but in that case, although the degree of freedom in assembling the vehicle is high, there is a problem that the number of parts increases. On the other hand, when the tank joint is also integrated, the number of parts is reduced, which is advantageous in terms of cost, and since the fuel inlet can be modularized and assembled, the assembling efficiency is improved.

[0009] In the fuel inlet of the present invention,
The metal pipe is preferably a stainless steel pipe in order to prevent rust. In this case, regarding the above-mentioned tank joint, it is preferable that the fuel cell is joined around the opening of the fuel tank by ring projection welding. That is,
If brazing is used to join the tank joint to the periphery of the fuel tank opening, the heat input time will be long, and the stainless steel base material will be affected by the heat, and chromium carbides will be unevenly distributed at the grain boundaries. In contrast, when ring projection welding is used, the heat input time is shorter and the heat affected range is narrower than when brazing is used, so that grain boundary cracking may occur. It is also advantageous in rust prevention function. That is, ring projection welding is preferable in that it brings out the goodness of the stainless steel pipe.

[0010] In the fuel inlet of the present invention,
Each part is formed by hydraulically bulging one metal pipe and compressing it in the axial direction, and the thickness of the vicinity of the part that has received the compressive load (fuel injection part or tank joint) must be thickened. preferable. Here, hydraulic bulge molding is
It refers to a processing method in which a pressure medium is put into a metal pipe to apply an internal pressure, so that the metal pipe is expanded on the inner wall of a die fixed outside to form a contour. In general, when a metal pipe is compressed in the axial direction, the thickness of the portion near the portion subjected to the compression load (for example, when a compressive load is applied in the axial direction from both ends of the metal pipe, the both ends correspond to the portion subjected to the compressive load) is thick. It becomes thick and the plate thickness becomes uneven.
For this reason, various techniques for preventing this and making the plate thickness uniform have been studied. On the contrary, here, on the contrary, taking advantage of the point where the plate thickness becomes non-uniform, the fuel injection portion is positively thickened. By making it thicker, excellent durability against abrasion due to the opening and closing operation of the lid of the fuel injection section is obtained. Also,
When the tank joint is also integrated, if this tank joint is a place to receive the above-described axial compression load,
Since the tank joint is also made thicker, its collision resistance (that is, its ability to prevent deformation due to impact upon collision) is improved.

[0011] The hydraulic bulge forming and the axial compression may be performed simultaneously or separately. For example, hydraulic bulge forming may be performed while compressing the metal pipe in the axial direction, axial compression may be performed after expanding the metal pipe by hydraulic bulging, or metal pipe may be compressed in the axial direction. The metal pipe after the hydraulic bulge forming may be further compressed in the axial direction.

In the fuel inlet of the present invention,
It is preferable that the fuel injection portion has a double pipe structure because the wear resistance of the fuel injection portion is further improved. This fuel inlet can be manufactured, for example, as follows.
That is, a short pipe was inserted on the side where the fuel injection section was formed, and a pressure medium (for example, water or oil) was supplied inside.
The metal pipe is placed in a mold for forming each part, and then the metal pipe is hydraulically bulged. Note that a compressive load may be applied in the axial direction during hydraulic bulge forming, or a compressive load may be applied in the axial direction after hydraulic bulge forming.

At this time, the fuel injection portion has a double pipe structure in which a reinforcing pipe is circumscribed, and the reinforcing pipe preferably reaches the opening edge of the fuel injection portion. In this case, the impact resistance is further improved as compared with the case where the opening edge of the fuel injection portion has a single pipe structure. By the way, when the reinforcing pipe is inscribed in the fuel injection part and has a double pipe structure, if the reinforcing pipe reaches the opening edge of the fuel injection part, the reinforcing pipe and the fuel injection part are connected to each other. Therefore, it is necessary to sufficiently enhance the sealing property between the reinforcing pipe and the fuel injection portion because the fuel vapor may leak to the outside through the gap. On the other hand, in the case where the reinforcing pipe is circumscribed to the fuel injection section to form a double pipe structure as described above, the fuel vapor passes through the gap between the reinforcing pipe and the fuel injection section and becomes external. Since there is no danger of leaking into the pipe, there is no need to particularly enhance the sealing property between the reinforcing pipe and the fuel injection section, and the manufacture is easy and the quality control is easy.

In the fuel inlet of the present invention,
After extending the opening edge of the fuel injection portion outward in the radial direction and then folding back along the axial direction, a substantially outer cylindrical outer folded portion is provided not as a separate body but as a single body, and in the fuel inlet support hole provided in the vehicle body When press-fitted, the outer folded portion may be pressed against the fuel inlet support hole. In this case, the substantially cylindrical outer folded portion serves as a conventional cylindrical cover. That is, when the fuel inlet is pressed into the fuel inlet support hole provided in the vehicle body from the fuel tank side, the outer folded portion is pressed against the fuel inlet support hole and is fixed so as to be relatively movable with respect to the vehicle body. Since this outer folded portion is formed by extending the fuel inlet itself,
The number of parts does not increase, and the step of assembling the parts into the fuel inlet is not required. Therefore, the cost can be reduced as compared with the case where the conventional cylindrical cover is used.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] FIG. 1 is a schematic explanatory view showing the appearance of the present embodiment (circles are partially enlarged sectional views). The fuel inlet 10 of the present embodiment includes a tank joining portion 11, a fuel injection portion 12, and a bellows portion 13,
Each part 11, 12, 13 is formed by one stainless steel pipe.

The tank joining portion 11 is formed in a flange shape at the end joined to the periphery of the opening 51 of the fuel tank 50. The tank joint 11 is joined to the periphery of the opening 51 of the fuel tank 50 by well-known ring projection welding. The fuel injection portion 12 is a portion into which a refueling nozzle (not shown) is inserted. The fuel injection portion 12 has a larger diameter at the end opposite to the end where the tank joining portion 11 is provided than at other portions. I have. The fuel injection section 12 is provided with a spiral groove 12a for screwing a lid (not shown) for closing the fuel injection section 12 except during refueling. Further, a breather tube 16 communicating with the fuel tank 50 is provided in a flat portion 12 b of the fuel injection portion 12, the tapered surface of which is partially flattened.

The bellows part 13 is provided between the tank joint part 11 and the fuel injection part 12 and near the tank joint part 11. The bellows portion 13 can be expanded and contracted in the axial direction and can be bent in the bending direction. Here, the fuel inlet 10 is manufactured in the following procedure. That is, first, a single stainless steel pipe shown in FIG. 2A is prepared, and a hydraulic bulge is formed while compressing both ends of the stainless steel pipe in the axial direction, thereby expanding the pipe substantially at the center thereof and near both ends thereof (one end thereof). (Corresponding to the tank joint 11). The state at this time is shown in FIG. Next, of the expanded portion (corresponding to the fuel injection portion 12), the boundary point B between the end opposite to the end corresponding to the tank joint 11 is directed toward the end corresponding to the tank joint 11. By compressing in the axial direction, the vicinity of the boundary (corresponding to the vicinity of the opening of the fuel injection part 12) is made thick. The state at this time is shown in FIG. Then, the bellows portion 1 is again formed by hydraulic bulging as shown in FIG.
Then, the fuel inlet 3 is formed and the shape is adjusted to obtain the fuel inlet 10.

As a result, the tank joint portion 11 and the fuel injection portion 12 are formed to be thicker than other portions, so that they have excellent wear resistance and impact resistance. The space (referred to as an intermediate portion 14) and the bellows portion 13 are formed to be thin and contribute to the weight reduction of the fuel inlet 10.

Next, an example of use of the fuel inlet 10 of the present embodiment will be described. At the time of refueling, a lid (not shown) screwed into the spiral groove 12a of the fuel injection part 12 is removed, and a fueling nozzle (not shown) is inserted into the fuel injection part 12 to perform refueling. When the fuel starts to be supplied to the fuel tank 50, the air in the fuel tank 50 is pushed out to the fuel injection unit 12 side via the breather tube 16. When the fuel is continuously supplied, the fuel eventually overflows from the opening of the breather tube 16 on the side of the fuel injection section 12. The fueler confirms this and ends the fueling work, and screws the lid into the spiral groove 12a. As described above, since the lid is opened and closed every time the lubrication operation is performed, wear resistance is required in the vicinity of the spiral groove 12a. However, since the vicinity of the spiral groove 12a is thickened, the requirement is sufficiently satisfied. It is something that can be done. In addition, the tank joint 11 welded to the tank 50 is required to have collision resistance (performance to prevent deformation due to an impact when a vehicle collides), and the tank joint 11 is also thickened. Therefore, the demand can be sufficiently satisfied.

The spiral groove 12a is disclosed in Japanese Patent Laid-Open No. 9-249.
As described in Japanese Patent Publication No. 036, while a mold (core metal) for forming a spiral groove is inserted into the fuel injection section 12, the roller surface of the rotating roller is pressed against the outer peripheral surface of the fuel injection section 12. It can be formed by rotating and moving along the shape of the cored bar. In addition, breather tube 1
6 is formed in the same manner as in the conventional example.

According to the embodiment described above, the following effects can be obtained. The fuel inlet 10 of the present embodiment is formed integrally with the metal bellows portion 13 having the same function as the rubber hose 105 (see FIG. 8).
It is possible to absorb the error at the time of assembling at a lower price than before and further prevent fuel permeation as compared with the conventional case. In the fuel inlet 10 of the present embodiment, in addition to the fuel injection part 12 and the bellows part 13, the number of parts is reduced as compared with the case where the tank joint 11 is formed separately by integrally forming the tank joint 11. This is advantageous in terms of cost, and since the fuel inlet 10 can be regarded as modularized, the assembling efficiency is also improved. Since the tank joint 11 is ring-projection welded to the periphery of the opening 51 of the fuel tank 50, the heat input time is short, and the heat affected range is narrow, so there is no risk of grain boundary cracking, and the stainless steel rust prevention function is also improved. It is advantageous. Since each of the parts 11, 12, and 13 is formed by performing hydraulic bulge forming and axial compression on a stainless steel pipe, the tank joint part 1 corresponding to a portion receiving a compressive load is formed.
1 and the fuel injection portion 12 are made thicker, and excellent wear resistance and collision resistance are obtained.

[Second Embodiment] FIG. 3 is an enlarged view of a tank joint according to a second embodiment. Since the second embodiment has the same configuration as the first embodiment except for the tank joining pipe 22,
The same components are denoted by the same reference numerals, and description thereof will be omitted.

The fuel inlet 20 of the present embodiment
Is provided with a fuel injection section 12 and a bellows section 13, and each section 12, 13 is formed by molding a single stainless steel pipe. Note that the forming process is substantially the same as in the first embodiment, and a description thereof will be omitted. As shown in FIG. 3, the fuel inlet 20 and the fuel tank 50 are joined by inserting a tank joining pipe 22 through an O-ring 21 at the end of the fuel inlet 20 opposite to the fuel injection section 12 side. In this state, it is performed by caulking the front and rear of the O-ring 21.
The bead 2 is placed before and after the O-ring 21 by caulking.
3, 24 are formed. The tank joining pipe 22 is a metal (stainless) pipe that is ring-projection welded around the opening 51 of the fuel tank 50.

According to the present embodiment, the effects of the first embodiment can be obtained, and the fuel injection portion 12 has excellent wear resistance and collision resistance because it is thickened. Furthermore,
In this embodiment, since the tank joining pipe 22 is separate from the fuel inlet 20, there is an advantage that the degree of freedom in assembling the vehicle is high. Whether the tank joint 11 is formed integrally with the fuel inlet 10 as in the first embodiment, or whether the tank joint pipe 22 is formed separately from the fuel inlet 10 as in the second embodiment, What is necessary is just to select suitably according to the shape of a vehicle, etc.

[Third Embodiment] FIG. 4 is an enlarged view of a fuel injection section according to a third embodiment. In the third embodiment, the fuel injection unit 1
Except for the structure 2, the configuration is the same as that of the first embodiment. Therefore, the same components are denoted by the same reference numerals and description thereof will be omitted.

The fuel inlet 30 of the present embodiment
Are the tank joint 11, the fuel injection part 12, and the bellows part 1.
The fuel injection section 12 has a double pipe structure with a short stainless steel pipe 31 (hereinafter referred to as a retainer) inserted therein. Each part 11, 12, 13 is formed by molding one stainless steel pipe. Note that the forming process is substantially the same as in the first embodiment, and a description thereof will be omitted. However,
In order to form the fuel injection section 12 into a double pipe structure, here, hydraulic bulge molding is performed using a stainless steel pipe into which a short retainer 31 is press-fitted in advance. In addition, the retainer 31 and the stainless steel pipe are described in Japanese Patent Application Laid-Open No. 9-249036.
This is caulked when the spiral groove 12a is formed by the method described in Japanese Unexamined Patent Publication (Kokai) Publication.

According to this embodiment, the first to fourth embodiments are explained.
In addition to the effect described above, the wear resistance of the fuel injection section 12 is further improved, and the bellows section 13 and the intermediate section 14 can be made thinner and lighter than in the first embodiment. [Fourth Embodiment] FIG. 5 is an enlarged view of a fuel injection section of a fourth embodiment. Since the fourth embodiment has the same configuration as the first embodiment except for the structure of the fuel injection unit 12, the same components are denoted by the same reference numerals and description thereof will be omitted.

[0028] The fuel inlet 40 of the present embodiment.
Are the tank joint 11, the fuel injection part 12, and the bellows part 1.
The fuel injection section 12 has a double pipe structure in which a short stainless steel pipe 41 (hereinafter referred to as a reinforcing pipe) is circumscribed. This reinforcement pipe 4
1 has reached the opening edge 12c of the fuel injection part 12. Each part 11, 12, 13 is formed by molding one stainless steel pipe. In addition,
Since the molding process is substantially the same as in the first embodiment,
The description is omitted. However, in order to form the fuel injection section 12 into a double pipe structure, hydraulic bulge molding is performed here using a stainless steel pipe in which a short reinforcing pipe 41 is extrapolated. The reinforcing pipe 41 and the stainless steel pipe are
It is swaged when the spiral groove 12a is formed by the method described in the above-mentioned Japanese Patent Application Laid-Open No. 9-249036.

According to this embodiment, the first to fourth embodiments will be described.
In addition to the effect described above, the wear resistance of the fuel injection section 12 is further improved, and the bellows section 13 and the intermediate section 14 can be made thinner and lighter than in the first embodiment. In addition, the opening edge 12c of the fuel injection portion 12 is folded back and formed in a flared shape. Since this portion also has a double pipe structure by the reinforcing pipe 41, the impact resistance of this portion is low. It is superior to the third embodiment. Here, in the third embodiment as well, the retainer 31 may reach the opening edge 12c of the fuel injection part 12, but the fuel vapor leaks to the outside through the gap between the retainer 31 and the fuel injection part 12. Therefore, it is necessary to sufficiently enhance the sealing property between the retainer 31 and the fuel injection section 12 because there is a possibility that it will come out. On the other hand, in the fourth embodiment, there is no possibility that the fuel vapor leaks to the outside through the gap between the reinforcing pipe 41 and the fuel injection section 12. There is no need to particularly enhance the sealing property, and there is an advantage that the production is easy and the quality control is easy.

The embodiments of the present invention are not limited to the above-described embodiments, and it goes without saying that various forms can be adopted as long as they fall within the technical scope of the present invention. For example, the tank joint 11 of the first embodiment may be joined to the periphery of the opening 51 of the fuel tank 50 with a bolt nut instead of ring projection welding. Also in this case, the problem of brazing (the possibility that the stainless steel base material is affected by heat and cause grain boundary cracking) does not occur, so that the rust prevention function of the stainless steel pipe is effectively exhibited.

Further, in the retainer 31 of the third embodiment, as shown in FIG. 6, the diameter of the opening on the back side may be reduced to form the interference portion 31a. The interference portion 31a is used in the case of an unleaded gasoline-only vehicle, and allows insertion of a refueling nozzle (small diameter) for unleaded gasoline, but refueling nozzle (large diameter) for leaded gasoline.
Insertion is prohibited.

At this time, as shown in FIG. 7, a substantially outer cylindrical outer folded portion 12d is formed by extending the opening edge 12c of the fuel injection portion 12 in the radially outward direction and then folding it along the axial direction.
May be provided not as a separate body but as the same body. The outer folded portion 12d is pressed into contact with the fuel inlet support hole when pressed into a fuel inlet support hole (not shown) provided in the vehicle body. As a result, the fuel inlet is fixed so as to be relatively movable with respect to the vehicle body. Since the outer folded portion 12d is formed by extending the fuel inlet itself, the number of components does not increase, and a step of assembling the outer inlet portion with the fuel inlet is not required. Therefore, the cost can be reduced as compared with a conventional case where a separate cylindrical cover is externally inserted into the fuel inlet and the cylindrical cover is press-fitted into the fuel inlet support hole. At this time, the spiral groove 12a may be provided only on the retainer 31.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a fuel inlet according to a first embodiment, in which a circle is a partially enlarged sectional view.

FIG. 2 is a manufacturing process diagram of the fuel inlet of the first embodiment.

FIG. 3 is a schematic perspective view of a fuel inlet according to a second embodiment, and a circle is a partially enlarged cross-sectional view.

FIG. 4 is a schematic perspective view of a fuel inlet according to a third embodiment, and a circle is a partially enlarged cross-sectional view.

FIG. 5 is a schematic perspective view of a fuel inlet according to a fourth embodiment, and a circle is a partially enlarged cross-sectional view.

FIG. 6 is a schematic perspective view showing another example of the third embodiment, and the inside of a circle is a partially enlarged sectional view.

FIG. 7 is a partially enlarged cross-sectional view showing another example of the third embodiment.

FIG. 8 is a schematic perspective view of a conventional fuel inlet.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Fuel inlet, 11 ... Tank joint part, 12 ... Fuel injection part, 12a ... Spiral groove, 1
3 ... bellows part, 14 ... middle part, 16 ... breather tube, 20 ... fuel inlet, 2
DESCRIPTION OF SYMBOLS 1 ... O-ring, 22 ... Tank joining pipe, 23, 2
4 ・ ・ ・ Bead, 30 ・ ・ ・ Fuel inlet, 3
1 ... Retainer, 31a ... Interference part, 50 ... Tank.

Claims (7)

[Claims] 1. A fuel inlet used for supplying fuel to a fuel tank of an automobile, wherein the diameter of the fuel inlet at the end opposite to the side joined to the periphery of the opening of the fuel tank is larger than that of another part. A fuel injection part into which a refueling nozzle is inserted, and a bellows part provided between an end part on the side joined to the opening of the fuel tank and an end part on the opposite side. A fuel inlet formed by molding one metal pipe. 2. A fuel inlet used for supplying fuel to a fuel tank of an automobile, wherein a tank joint provided at an end on a side joined to a periphery of an opening of the fuel tank; At the end opposite to the end provided, formed with a larger diameter than the other part, between the fuel injection part into which the refueling nozzle is inserted, and between the tank joint and the opposite end And a bellows portion provided in the fuel inlet, wherein each of the portions is formed by molding one metal pipe. 3. The fuel inlet according to claim 2, wherein the metal pipe is a stainless steel pipe, and the tank joint is joined to a periphery of an opening of the fuel tank by ring projection welding. Inlet. 4. The fuel inlet according to claim 1, wherein each of the parts is formed by hydraulically bulging one metal pipe and compressing the same in an axial direction, and receives a compressive load. The fuel inlet is characterized by being thickened in the vicinity of the place where it is located. 5. The fuel inlet according to claim 1, wherein the fuel injection section has a double pipe structure. 6. The fuel inlet according to claim 5, wherein the fuel injection portion has a double pipe structure in which a reinforcing pipe is circumscribed, and the reinforcing pipe has an opening edge of the fuel injection portion. Fuel inlet characterized by reaching to. 7. The fuel inlet according to any one of claims 1 to 6, wherein the fuel injection portion has a substantially outer cylindrical shape in which an opening edge of the fuel injection portion extends outward in a radial direction and then is turned back along an axial direction. The fuel inlet according to claim 1, wherein the outer folded portion is provided not as a separate body but as a single body, and the outer folded portion is pressed into contact with the fuel inlet support hole when the outer folded portion is press-fitted into a fuel inlet support hole provided in the vehicle body.