JP3389743B2 - Fuel tank - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fuel tank for an automobile.

[0002]

2. Description of the Related Art Generally, a swirl tank is attached to a bottom wall of a tank body in a fuel tank, and even if the fuel is biased to one side due to centrifugal action or the like when the vehicle is turning, the suction of a fuel pump is hindered. The required amount of fuel is always stored so as not to do so. Conventionally, as a fuel tank provided with such a swirl tank, for example, there is one shown in FIGS. 7 and 8 (see Japanese Utility Model Laid-Open No. 61-57034).

FIG. 7 is a cross-sectional view of a part of the fuel tank with the swirling tank as the main body, and FIG. 8 is an enlarged plan view of the swirling tank.

First, as shown in FIG.
The bottom portion 101a is fixed to the fuel tank body 103, and the top portion is opened to form an opening portion 101b. Further, the swirling tank main body 101 is provided with a fuel passage 101c on the lower portion 101a side. The fuel pump 105 is installed in the fuel tank.
Is provided, and the suction side of the fuel pump 105 is arranged in the swirling tank main body 101. A feed pipe 107 is connected to the discharge side of the fuel pump 105 and extends to the engine room side. The feed pipe 107 is connected to the injector 109 of the engine, and the injector 1
Reference numeral 09 is for injecting fuel into the intake manifold 111 of the engine. A return pipe 113 is connected to the feed pipe 107. A pressure regulator 115 is provided on the return pipe 113, and a tip 113 a thereof faces the inside of the swirling tank body 101.

The fuel sucked and pumped by the fuel pump 105 reaches the injector 109 through the feed pipe 107, and is injected into the intake manifold 111. Excess fuel that has not been injected among the pressure-fed fuel is pressure-regulated by the pressure regulator 115, and is fed by the return pipe 113 to the swirling tank main body 1
It is refluxed to the 01 side, and the swirling tank body 101 is fed from the tip 113a
Flows in. The inflow of fuel from the fuel tank main body 103 side into the swirl tank main body 101 flows in from the opening 101b when the fuel is higher than the height of the swirl tank main body 101, and also from the fuel flow channel 101c. Further, when the amount of fuel decreases and the liquid level becomes lower than the height of the swirl tank body 101, the fuel flows into the swirl tank body 101 only from the fuel flow channel 101c. When the fuel in the fuel tank main body 103 is exhausted by a centrifugal action or the like, the
Although the liquid surface inclines as shown by, the sufficient fuel is secured in the swirling tank main body 101 at this time as well, and it is possible to prepare for swirling traveling and downhill driving.

By the way, in the structure of the swirling tank as described above, it is difficult to suppress the increase of vapor generated in the fuel tank main body 103. That is, the fuel pump 10
The fuel pressurized by No. 5 is about 40 ° C., but the ambient temperature in the engine room is about 80 ° C., and heat is exchanged while the fuel passes through the engine room, and the high temperature return fuel is the swirling tank body. It will return to 101. This high-temperature return fuel causes the main body 1
This is because when the high temperature return fuel overflows into the fuel tank main body 103 from the opening 101b of 01 and diffuses to the fuel surface in the fuel tank main body 103, vapor is generated over the wide liquid surface in the fuel tank main body 103.

In this case, the relationship between the fuel temperature and the vapor generation amount is as shown in FIG. 3, and the vapor generation amount tends to increase as the fuel temperature increases.

On the other hand, the present applicant has proposed a fuel tank having a swirling tank as shown in FIG. In FIG. 9, the swirling tank body 117 is formed in a divided structure of an upper cap 119 as an upper part and a chamber body 121 as a lower part, and return fuel is circulated by a so-called jet pump 123. The jet pump 123 includes an introduction port 125 provided in the chamber body 121, and the nozzle 12 whose tip faces the introduction port 125.
It consists of 7. A gap 129 exists between the nozzle 127 and the introduction port 125, and the fuel around it can be drawn in by the jet flow from the nozzle 127. The nozzle 127 is provided at the tip of the return pipe 113. The fuel pump 105 is supported by the upper cap 119.

The fuel in the swirl tank body 117 is pumped by the fuel pump 105 in the same manner as described above. On the other hand, the return fuel is accelerated from the nozzle 127 and is recirculated into the swirling tank body 117. The overflow of fuel from the upper part of the swirling tank body 117 can be suppressed by the upper cap 119.

[0010]

However, in the structure using the jet pump 123 as described above, the fuel is recirculated from the nozzle 127 at a predetermined injection output, and further the fuel around the swirling tank body 117 is output as the injection output. Since the fuel is drawn in and introduced into the swirling tank main body 117 from around the nozzle 127, the fuel has a considerable momentum. Therefore, the swirling tank body 11
From within 7, the upper cap 119 and the chamber body 121
Fuel overflows to the outside of the swirling tank main body 117 from the gaps 131 and 133 between the fuel tank main body 103 and the like, and comes into contact with the air in the fuel tank main body 103, increasing the amount of vapor generation. Therefore, even in this case, there is a limit to the suppression of vapor generation.

Therefore, an object of the present invention is to provide a fuel tank capable of greatly suppressing the amount of vapor generated.

[0012]

[0013]

[0014]

[0015]

[0016]

According to a first aspect of the present invention, there is provided a sealed swirling tank body provided on a bottom wall of the fuel tank body, a fuel pump for pumping the fuel in the swirling tank body, and A flow path for guiding the pressure-fed fuel to the engine side and for recirculating excess fuel not used in the engine, an inlet provided on the bottom side of the swirling tank body and communicating with the inside and outside of the swirling tank body, and a tip at the introducing port And a jet pump formed of a nozzle that guides the recirculating fuel into the inlet and guides the fuel in the fuel tank main body into the inlet from around the inlet,
The swirl tank main body has at least a selective communication between the inside and the outside of the swirl tank main body, and has a discharge port opening to the bottom wall side in the main body of the fuel tank, and the excess fuel in the swirl tank main body is removed from the fuel tank main body. Discharging means for discharging into the inside is provided, one end of the discharging means is attached to an opening formed in the upper wall of the swirling tank main body, and the discharge port side of the other end extends to the bottom wall side in the fuel tank main body. It is characterized in that it is composed of a tube that is formed.

Therefore, since the swirling tank body is hermetically sealed,
The fuel does not flow out of the swirl tank main body through the gap. Well
Also, make sure that excess fuel is discharged to the bottom wall of the fuel tank body.
The contact between the excess fuel and the air in the fuel tank body
Can be suppressed. Further , since the discharging means is composed of the tube attached to the opening formed in the upper wall of the swirling tank main body, when the fuel in the swirling tank main body is not stored up to the opening, the swirling tank main body The fuel inside is not discharged from the swirl tank body. Further, when the fuel in the swirl tank main body is stored up to the opening, the fuel flows into the tube through the opening and is discharged to the outside of the swirl tank main body from the outlet opening on the bottom wall side in the fuel tank main body. Is discharged. Furthermore, since the discharging means is composed of a tube,
There is flexibility in the arrangement of the discharge means.

According to a second aspect of the present invention, a closed swirling tank body is provided on the bottom wall of the fuel tank body, a fuel pump for pumping the fuel in the swirling tank body, and the pumped fuel for the engine. Flow passage for guiding the excess fuel not used in the engine, and an inlet provided on the bottom side of the swirling tank body for communicating the inside and outside of the swirling tank body, and a tip facing the introducing port and the reflux. A fuel tank comprising a jet pump including a nozzle that guides the fuel in the fuel tank body from the periphery of the inlet to the inside of the inlet while flowing the fuel into the inlet, in the swirling tank body,
At least selectively communicating with the inside and outside of the swirling tank body,
The fuel tank has a discharge port opening to the bottom wall side in the main body, and discharge means for discharging excess fuel in the swirl tank main body into the fuel tank main body is provided. The discharge port formed in the lower part of the side wall and a non-return valve which is attached to the discharge port and allows the discharge of fuel from the discharge port when the pressure inside the swirling tank main body becomes higher than the pressure outside the swirling tank main body by a certain amount or more. It is characterized by being composed of a valve.

Therefore, since the swirling tank body is hermetically sealed,
The fuel does not flow out of the swirl tank main body through the gap. Well
Also, make sure that excess fuel is discharged to the bottom wall of the fuel tank body.
The contact between the excess fuel and the air in the fuel tank body
Can be suppressed. Further , since the discharging means is composed of a check valve that allows the fuel to be discharged from the discharge port when the pressure inside the swirling tank body becomes higher than the pressure outside the swirling tank body by a certain amount or more, The pressure inside the swirl tank main body does not become higher than the pressure outside the swirl tank main body by a certain amount until the amount of fuel in the swirl tank main body reaches a certain amount, and excess fuel in the swirl tank main body is discharged from the check valve. There is no. In addition, when the fuel in the swirl tank body reaches a certain amount of storage and the pressure inside the swirl tank body becomes higher than the pressure outside the swirl tank body by a certain amount or more, the check valve opens and the inside of the swirl tank body opens. Surplus fuel is discharged.

The invention of claim 3 is the fuel tank according to claim 1 or 2 , wherein the discharge port is located in the vicinity of the introduction port.

Therefore, since the discharge port is located near the introduction port, the high temperature surplus fuel discharged from the discharge port is returned to the swirling tank body together with the return fuel before being diffused into the fuel tank body. . Further, when there is no fuel in the fuel tank body, the excess fuel discharged from the discharge port is returned to the swirling tank body again by the fuel ejected from the nozzle.

According to a fourth aspect of the present invention, in the fuel tank according to any one of the first to third aspects, the swirl tank body has a vertically divided structure, and an upper portion and a lower portion are sealed with a seal. It has a feature.

Therefore, since the fuel pump is supported by the upper portion through the seal, it is possible to prevent the fuel in the swirling tank body from leaking through the gap formed between the upper portion and the fuel pump. Further, the fuel pump and the upper part can be handled integrally. According to a fifth aspect of the present invention, a closed swirl tank body provided on a bottom wall in the fuel tank body, a fuel pump for pumping the fuel in the swirl tank body, and the fuel pumped to the engine side. Along with this, a flow path for recirculating excess fuel not used in the engine, an inlet provided on the bottom side of the swirl tank main body for communicating the inside and outside of the swirl tank main body, and a fuel having the tip facing the inlet and the recirculating fuel are introduced. A fuel tank comprising a jet pump including a nozzle that causes the fuel in the fuel tank body to flow into the inlet from the periphery of the inlet while at least selectively being provided in the swirl tank body. A discharge means is provided for communicating the inside and the outside and having a discharge opening that opens to the bottom wall side in the fuel tank main body, and discharge means for discharging excess fuel in the swirl tank main body into the fuel tank main body. The tank body has a top and bottom of the divided structure is characterized in that sealed with the seal between the upper and lower. Therefore, since the swirl tank body is hermetically sealed, fuel does not flow out of the swirl tank body through the gap. Further, since the surplus fuel is discharged to the bottom wall of the fuel tank body, it is possible to suppress contact between the surplus fuel and the air in the fuel tank body. Further, since the fuel pump is supported by the upper portion via the seal, it is possible to prevent the fuel in the swirling tank main body from leaking from the gap formed between the upper portion and the fuel pump. Further, the fuel pump and the upper part can be handled integrally.

A sixth aspect of the present invention is the fuel tank according to the fourth or fifth aspect , wherein the fuel pump is supported on the upper portion via a seal.

Therefore, by sealing the swirl tank main body by providing a seal between the upper portion and the lower portion, it is possible to prevent the fuel in the swirl tank main body from leaking from the gap generated between the upper portion and the lower portion by the seal.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
It is a principal part sectional view of the fuel tank according to the embodiment. The basic structure of the fuel tank shown in FIG. 1 is substantially the same as that shown in FIG. 9, and includes a swirling tank body 1, a fuel pump 3, and a jet pump 5. Also, in particular, a discharging means 7 is provided.

The swirling tank main body 1 is of a two-piece construction including an upper cap 9 which constitutes an upper part and a chamber body 11 which constitutes a lower part, and is hermetically sealed. That is, the convex portion 1 for fitting is provided on the lower surface of the outer peripheral portion of the upper cap 9.
3 is formed over the entire circumference. A concave portion 15 is formed in the convex line portion 13 and holds an O-ring 17 for sealing. The O-ring 17 is in close contact with the entire inner circumference of the chamber body 11. A pump holding portion 19 is provided on the upper cap 9 in an inclined manner. A second ridge portion 21 for fitting the pump is provided on the inner circumference of the pump holding portion 19. A recess 23 is provided in the second protruding portion 21, and an O-ring 25 for sealing is supported. This O-ring 25
Is in close contact with the entire outer peripheral surface of the fuel pump 3. The fuel pump 3 is fixed to the ridges 21 and the like by fixing means (not shown).

A convex portion 27 is provided on one side of the upper cap 9.
Is provided. The inner surface of the convex portion 27 is a concave curved surface 27.
a, and guides the fuel to the discharge means 7.

The filter 3b attached to the suction pipe 3a of the fuel pump 3 is in contact with the bottom of the swirling tank body 1, that is, the bottom wall 11a of the chamber body 11. The feed pipe 107 connected to the discharge port side of the fuel pump 3 constitutes a flow path together with the return pipe 113,
Fuel injected by the engine 1
09, and the excess fuel is returned to the swirling tank body 1 side. 111 is an intake manifold, and 115 is a pressure regulator.

The jet pump 5 is a chamber body 1.
It is composed of an inlet 29 formed in the side wall 11b of No. 1 and a nozzle 31 provided at the tip of the return pipe 113. The introduction port 29 extends into the chamber body 11 by an introduction passage 33, and communicates with the inside of the chamber body 11 via an introduction opening 35 at an end portion. Bottom wall 3 of introduction passage 33
3a is located slightly above the bottom wall 11a of the chamber body 11. The inlet 29 is formed in an enlarged shape that is curved over the entire circumference. The nozzle 31
Has its tip slightly exposed to the inside of the introduction port 29, and has a gap 37 between it and the introduction port 29. In addition, the nozzle 3
The outer surface 31a of No. 1 is tapered toward the inlet 29, so that the fuel around the nozzle 31 can be easily introduced into the inlet 29.

The discharge means 7 is formed by a discharge cylinder 39 which is erected on one side in the swirl tank body 1.
The discharge tube 39 rises integrally from the bottom wall 11a of the chamber body 19, and the discharge tube opening 39a at the upper end faces the concave curved surface 27a of the upper cap 9. A horizontal passage 41 is connected to a lower portion of the discharge pipe 39, and
A discharge port 43 is formed at the end of No. 1. Lateral passage 4
1 is formed between the bottom wall 11a of the chamber body 11 and the bottom wall 103a of the fuel tank body 103 by forming the passage curved portion 45 as shown in FIGS. Therefore, the discharge port 43 at the end of the fuel tank body 1
It is configured to open to the bottom wall 103a side in 03.
Further, in this embodiment, the discharge cylinder 39 constituting the discharge means 7 is always open from the discharge cylinder opening 39a to the discharge port 43.

Next, the operation will be described.

In this embodiment, fuel is introduced into the swirl tank body 1 from the introduction port 29. That is, the return fuel is ejected from the nozzle 31, passes through the introduction passage 33, and flows into the swirl tank body 1 from the introduction opening 35. Also,
The fuel in the fuel tank body 103 is drawn from the periphery of the nozzle 31 into the inlet 29 by the return fuel ejected from the nozzle 31, and similarly flows into the swirling tank body 1. At this time, the outer surface 31a of the nozzle 31 is tapered toward the inlet 29, so that the fuel can be smoothly drawn from around the nozzle 31. It should be noted that in the state where the fuel in the fuel tank main body 103 is exhausted and the fuel remains only in the swirling tank main body 1, the fuel in the fuel tank main body 103 is not sucked from around the nozzle 31, and The air in the fuel tank main body 103 is guided into the swirling tank main body 1 along with the jetting of the return fuel.

The fuel introduced into the swirl tank main body 1 is formed in the swirl tank main body 1 by the upper cap 9 and the chamber body 11 and is sealed by the O-rings 17 and 25. Even when the vehicle is turning, it does not overflow from the space between the upper cap 9 and the chamber body 11 to the outside of the turning tank body 1. Moreover, when the return fuel is large and the fuel reaches the upper cap 9, the fuel is guided by the concave curved surface 27a of the convex portion 27, and the fuel is discharged into the discharge pipe 39 from the discharge pipe opening 39a of the discharge pipe 39. It The fuel thus guided into the discharge tube 39 is discharged from the discharge port 43 into the fuel tank main body 103 through the lateral passage 41. Since the discharge port 43 is located on the side of the bottom wall 103a of the fuel tank body 103, the discharged fuel can be guided below the liquid surface of the fuel having a relatively low temperature and does not diffuse on the liquid surface. It is possible to suppress the generation of vapor over the entire surface. That is, it is possible to prevent replacement of the high-temperature return fuel with the fuel on the outer surface of the swirling tank body 1, and to suppress the amount of vapor generation. Further, the high-temperature return fuel is the fuel tank body 103.
It is possible to prevent contact with the air inside and suppress the amount of vapor generated.

The high-temperature fuel flowing into the swirl tank body 1 is sucked as it is by the fuel pump 3 without being diffused to the outside of the swirl tank body 1, and is again pumped to the engine side. Therefore, the amount of heat received in the engine room can be reduced, and the generation of vapor due to heat diffusion into the fuel tank can be suppressed.

The swirling tank body 1 has a closed structure,
Moreover, since the jet pump 5 is used, the fuel that has flowed into the swirl tank body 1 is reliably stored, so that sufficient fuel is stored in the swirl tank body 1 even if centrifugal force or the like during vehicle turning acts. Therefore, the fuel can be sucked by the fuel pump 3 without difficulty even when the vehicle is running at the limit when the fuel is extremely low.

FIG. 3 compares the amount of vapor generated with the conventional example of FIG. 9 and shows the result of the first embodiment. Thus, as is clear from comparison with the conventional example, in the case of the present embodiment, the amount of vapor generation could be greatly suppressed.

In assembling the swirling tank, first, with the upper cap 9 removed from the chamber body 11, the fuel pump 3 is attached via the O-ring 25 to the pump holding portion 19.
Can be installed on. Then, the upper cap 9 to which the fuel pump 3 is attached is attached to the chamber body 11 via the O-ring 17. Therefore, the O-rings 17 and 25 can be handled separately and the assembly is easy.

Next, another embodiment will be described. The same components as those of the first embodiment will be described with the same reference numerals, and duplicate description will be omitted.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
3 is a sectional view of a main part of the fuel tank according to the embodiment. FIG.
In this embodiment, the discharge means 7 is composed of the tube 47. The tube 47 includes a connecting portion 47a, a horizontal portion 47b, and a downward extending portion 47c. Connecting part 4
7a is connected to a discharge opening 49 formed in the upper cap 9 which is the upper wall of the swirl tank body 1. That is,
The opening 49 is provided with a connecting convex portion 49a, and the tube 4
The connecting portion 47a of 7 is fitted and connected. Tube 47
The horizontal portion 47b extends laterally of the swirling tank body 1, and the downward extending portion 47c extends downward on one side of the swirling tank body 1. A discharge port 43 is provided at the lower end of the downwardly extending portion 47c.
Is formed and is located on the bottom wall 103a side of the fuel main body 103. It should be noted that this embodiment also uses the tube 4 of the discharging means 7.
7 always opens from the opening 49 to the outlet 43.

Therefore, in this embodiment, the swirling tank body 1
The surplus fuel inside is discharged from the discharge opening 43 through the tube 47 and the discharge port 43 to the bottom wall 10 of the fuel tank main body 103.
It can be discharged to the 3a side. Therefore, this embodiment can have substantially the same operational effects as the first embodiment. Moreover, in this embodiment, since the tube 47 is connected to the discharge opening 49 of the upper cap 9, more fuel can be stored in the swirl tank body 1. Furthermore, since only the discharge opening 49 is provided on the swirl tank main body 1 side, the shape of the swirl tank main body 1 is also simplified, and the manufacturing is facilitated.

(Third Embodiment) FIG. 5 shows a third embodiment of the present invention.
1 illustrates an embodiment. In this embodiment, the discharge means 7 is composed of the discharge port 43 and the check valve 51. The discharge port 43 is provided on the lower side of the side wall 11b of the chamber body 11 in the swirl tank body 1, and the check valve 51 is attached to the discharge port 43. Therefore, in this embodiment,
The inside and outside of the swirling tank body 1 are selectively communicated with each other.

In this embodiment, when a predetermined amount of fuel is stored in the swirling tank body 1, the check valve 51 is turned on.
It is opened by the pressure difference between the inside and the outside, and the surplus fuel is discharged from the discharge port 43 to the bottom wall 103a side of the fuel tank body 103. Therefore, also in this embodiment, it is possible to obtain substantially the same operational effects as in the first embodiment. Also,
In this embodiment, the discharging means 7 is extremely compact and has a space-efficient structure.

(Fourth Embodiment) FIG. 6 shows a fourth embodiment of the present invention.
1 illustrates an embodiment. In this embodiment, the inlet 29
The discharge port 43 is located in the vicinity of. That is, the discharge port 43 is provided on the outer side of the introduction port 29 and immediately above it. A discharge tube 39 is erected on the discharge port 43.

Since the relationship between the upper cap 9 and the chamber body 11 in the fourth embodiment is slightly different from that in the above embodiment, a brief description will be given here.
In this embodiment, the sealing between the upper cap 9 and the chamber body 11 is performed by close fitting.
That is, the close fitting portion 53 having a predetermined length is formed on the outer peripheral portion of the upper cap 9. The close-fitting fitting portion 53 is formed by inner and outer close-contact pieces 53a and 53b, and the outer close-fitting piece 53.
b is formed longer than the inner contact piece 53a. The close fitting portion 53 is tightly fitted to the upper edge portion of the chamber body 11 to achieve a hermetically sealed structure. The pump holding portion 19 of the fuel pump 3 is formed on one side of the swirl tank body 1, that is, the inlet 29 side, and the fuel pump 3 is held by the pump holding portion 19 by a fixing means (not shown) via a seal body 55. It is covered by the seal cap 57.

Excess fuel in the swirl tank body 1 is introduced into the discharge pipe 39 through the discharge pipe opening 39a of the discharge pipe 39,
It flows out from the discharge port 43 at the lower end. The surplus fuel that has flowed out is drawn in by the return fuel ejected from the nozzle 31, and is introduced into the swirling tank main body 1 as it is.

Therefore, also in this embodiment, it is possible to obtain substantially the same operational effects as those of the first embodiment and the like. Also,
Since the surplus fuel in the swirl tank body 1 is not discharged to the outside of the swirl tank body 1, the heat of the return fuel does not diffuse to the outside of the swirl tank body 1 and the generation of vapor can be suppressed more reliably. it can. Further, the introduction port 2 into the swirl tank main body 1
Since the surplus fuel and the return fuel introduced from 9 are directly sucked by the fuel pump 3, it is possible to further suppress the heat exchange amount in the engine room, and also from this point, it is possible to further suppress the vapor generation amount. it can.

[0049]

[0050]

[0051]

According to the first aspect of the present invention, the return fuel having a high temperature is pumped as it is to the engine side by the fuel pump unless it is discharged by the discharging means, so that the amount of heat received in the engine room can be reduced. . Further, since the swirl tank body is hermetically sealed, it is possible to prevent the return fuel from coming into contact with the air in the fuel tank body. Further, due to the closed structure of the swirl tank main body and the fuel recirculation by the jet pump, replacement of the high temperature return fuel with the fuel outside the swirl tank main body can be suppressed even during swirling. Further, the fuel discharged from the discharging means can be guided to the bottom wall side in the fuel tank body, that is, below the liquid surface. By these, the amount of vapor generation can be greatly suppressed. Moreover, the structure of the swirling tank main body can be simplified.

According to the second aspect of the present invention, the return fuel having a high temperature is pumped as it is to the engine side by the fuel pump unless it is discharged by the discharging means, so that the amount of heat received in the engine room can be reduced. Also,
Since the swirl tank body is hermetically sealed, it is possible to suppress the return fuel from coming into contact with the air in the fuel tank body. Further, due to the closed structure of the swirl tank main body and the fuel recirculation by the jet pump, replacement of the high temperature return fuel with the fuel outside the swirl tank main body can be suppressed even during swirling. Further, the fuel discharged from the discharging means can be guided to the bottom wall side in the fuel tank body, that is, below the liquid surface.
By these, the amount of vapor generation can be greatly suppressed. In addition, the installation space of the discharge means can be reduced, and a space-friendly structure can be provided.

According to the third aspect of the invention, in addition to the effect of the first or second aspect of the invention, the fuel discharged from the discharge port is immediately introduced into the swirling tank main body from the introduction port, so that the diffusion of the return fuel is more reliable. The heat exchange in the engine room can be suppressed. Therefore, the amount of vapor generation can be suppressed more reliably.

According to the invention of claim 4 , in addition to the effects of the inventions of claims 1 to 3 , the upper part of the main body of the swirling tank can be removed, and the assembling and the like can be easily performed.
In the invention of claim 5 , the return fuel having a high temperature is pumped to the engine side as it is by the fuel pump unless it is discharged by the discharge means, so that the amount of heat received in the engine room can be reduced. Further, since the swirl tank body is hermetically sealed, it is possible to prevent the return fuel from coming into contact with the air in the fuel tank body. Further, due to the closed structure of the swirl tank main body and the fuel recirculation by the jet pump, replacement of the high temperature return fuel with the fuel outside the swirl tank main body can be suppressed even during swirling. Also,
The fuel discharged from the discharging means can be guided to the bottom wall side in the fuel tank body, that is, below the liquid surface. By these, the amount of vapor generation can be greatly suppressed. Also,
The upper part of the swirling tank main body can be removed, and the assembling can be easily performed.

According to the invention of claim 6 , claim 4 or 5
In addition to the effect of the invention described above, even if the swirling tank main body is separated from the fuel tank in the event of a vehicle collision, the fuel pump can be supported on the swirling tank main body side through the seal, and the fuel supply can be maintained. Can be possible.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a fuel tank according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along the line II-II of FIG.

FIG. 3 is a graph showing a reduction in vapor generation amount as compared with a conventional example.

FIG. 4 is a cross-sectional view of main parts of a fuel tank according to a second embodiment.

FIG. 5 is a cross-sectional view of essential parts of a fuel tank according to a third embodiment.

FIG. 6 is a sectional view of relevant parts of a fuel tank according to a fourth embodiment.

FIG. 7 is a sectional view of a main part of a fuel tank according to a conventional example.

FIG. 8 is a plan view of a swirling tank according to a conventional example.

FIG. 9 is a cross-sectional view of main parts of a fuel tank according to another conventional example.

[Explanation of symbols]

1 Swirling tank body 3 fuel pump 5 Jet pump 7 discharge means 9 Upper cap (upper) 11 Chamber body (bottom) 29 entrance 39 discharge tube 43 outlet 47 tubes 51 Check valve 103 Fuel tank body

Claims (6)

(57) [Claims] 1. A seal provided on a bottom wall in a fuel tank body.
A closed swirl tank body and the fuel in the swirl tank body are pressure-fed.
Fuel pump and guide the pumped fuel to the engine side
A flow that recirculates excess fuel not used in the engine with
And a swirling tank body provided on the bottom side of the swirling tank body.
Of the inlet that communicates the inside and outside of the
Introduce the recirculated fuel into the inlet while introducing it.
Fuel in the fuel tank body from around the mouth into the inlet
Fuel with a jet pump consisting of a guiding nozzle
In the tank, the swirling tank body is at least selectively
And open to the bottom wall side inside the fuel tank body.
It has a discharge port to discharge excess fuel in the swirling tank body
Discharging means for discharging into the material tank body is provided, and the discharging means is an opening formed on the upper wall of the swirling tank body.
One end is attached to the mouth and the other end is the fuel tank.
A fuel tank comprising a tube extending to the bottom wall side inside the main body . 2. A seal provided on a bottom wall in the fuel tank body.
A closed swirl tank body and the fuel in the swirl tank body are pressure-fed.
Fuel pump and guide the pumped fuel to the engine side
A flow that recirculates excess fuel not used in the engine with
And a swirling tank body provided on the bottom side of the swirling tank body.
Of the inlet that communicates the inside and outside of the
Introduce the recirculated fuel into the inlet while introducing it.
Fuel in the fuel tank body from around the mouth into the inlet
Fuel with a jet pump consisting of a guiding nozzle
In the tank, the swirling tank body is at least selectively
And open to the bottom wall side inside the fuel tank body.
It has a discharge port to discharge excess fuel in the swirling tank body
Discharging means for discharging into the material tank body is provided, and the discharging means is formed at a lower portion of a side wall of the swirling tank body.
Inside the main body of the swirl tank attached to the discharge port
Pressure is higher than the pressure outside the main body of the swirling tank by a certain amount.
It is composed of a check valve that allows the discharge of fuel from the discharge port when
The fuel tank is characterized by 3. The fuel tank according to claim 1 or 2.
Thus, the fuel tank is characterized in that the discharge port is located in the vicinity of the introduction port . 4. The fuel tank according to claim 1.
The main body of the swirling tank has a vertically divided structure, and the upper and lower parts
A fuel tank characterized in that the space is sealed with a seal . 5. A seal provided on a bottom wall in the fuel tank body.
A closed swirl tank body and the fuel in the swirl tank body are pressure-fed.
Fuel pump and guide the pumped fuel to the engine side
A flow that recirculates excess fuel not used in the engine with
And a swirling tank body provided on the bottom side of the swirling tank body.
Of the inlet that communicates the inside and outside of the
Introduce the recirculated fuel into the inlet while introducing it.
Fuel in the fuel tank body from around the mouth into the inlet
Fuel with a jet pump consisting of a guiding nozzle
In the tank, the swirling tank body is at least selectively
And open to the bottom wall side inside the fuel tank body.
It has a discharge port to discharge excess fuel in the swirling tank body
Discharging means for discharging into the material tank body is provided, and the swirling tank body has a vertically divided structure, and the upper and lower parts
A fuel tank characterized in that the space is sealed with a seal . 6. The fuel tank according to claim 4 or 5.
The fuel pump is supported on the top through a seal.
The fuel tank is characterized by