JPH07279788A - Fuel tank - Google Patents

Abstract

PURPOSE:To restrain an excessive fuel filling preventing valve from being large-sized and heavier, and to prevent the valve from sticking and a fuel level in a filler tube from rising in the case where temperature in a tank body rises. CONSTITUTION:A shutter 8 opened by inserting a fuel filling gun 6 is provided at the upper end of a filler tube 5. A vent tube 3 for making an upper space in a tank body 1 communicate with a canister 2 is provided. All excessive fuel filling preventing valve 4 is provided at the end facing the inside of the tank body 1 of the vent tube 3. A vent cut valve 7 to shut off the pipe line of the vent tube 3 interlockingly with the opening and closing of the shutter 8 is provided on the way of the pipe line of the vent tube 3. A gap 20 for making a space between the excessive fuel filling preventing valve 4 in the vent tube 3 and the vent cut valve 7 communicate with an upper space in the filler tube 5 is provided on the side wall of the filler tube 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a fuel tank used in automobiles and the like.

[0002]

2. Description of the Related Art As a fuel tank of this type, a fuel tank shown in FIG.
The ones shown in are devised.

In this fuel tank, a vent tube 3 which connects the inside of the tank body 1 and the canister 2 is attached to the upper part of the tank body 1, and a large amount of evaporated fuel generated at the time of refueling the fuel is passed through the vent tube 3 to the canister 2. The vent tube 3
At the end facing the inside of the tank body 1, there is provided a super-lubrication prevention valve 4 that closes the end of the vent tube 3 when the fuel level in the tank body 1 exceeds a set height. A vent cut valve 7 that opens the pipeline only when the fuel filling gun 6 is inserted into the filler tube 5 is provided in the middle of the passage. The vent cut valve 7 is attached to the upper side wall of the filler tube 5 and is adapted to interlock with the opening / closing operation of the shutter 8 attached to the upper end of the filler tube 5, and the refueling gun 6 pushes the shutter 8 at the time of refueling. When opened, the vent tube 3 is opened to allow the vaporized fuel gas to be guided from the tank body 1 to the canister 2.

Therefore, in this fuel tank,
When fuel is not refueled, the vent cut valve 7 closes the middle of the conduit of the vent tube 3, and at the time of fuel refueling, the vent cut valve 7 opens the conduit of the vent tube 3 and the fuel in the tank body 1 is closed. The fuel vapor gas in the tank main body 1 is guided to the canister 2 until the liquid level becomes equal to or higher than the set height and the supercharging prevention valve 4 closes the end portion of the vent tube 3. When the overfilling prevention valve 4 blocks the vent tube 3, the filler tube 5
The liquid level inside rises to near the upper end thereof, and the rise of the liquid level is detected by an automatic stop sensor (not shown) of the fuel refueling gun 6 to stop the refueling of the fuel.

Incidentally, this similar technique is disclosed in, for example, Shokai Sho 63.
-26762 and JP-A-62-29418.

[0006]

In the conventional fuel tank described above, when the shutter 8 is closed with the overfilling prevention valve 4 closing the end of the vent tube 3, the vent cut valve 7 interlocked with the shutter 8 is closed. Is vent tube 3
That is, the middle of the pipe line is closed, and the pipe line between the supercharging prevention valve 4 and the vent cut valve 7 of the vent tube 3 is sealed. Therefore, in the above-described conventional fuel tank, even if the fuel level in the tank body 1 is lowered, the over-fueling prevention valve 4 prevents the so-called sticking in which the vent tube 3 remains closed. There was no choice but to increase the size and weight of the valve 4.

Further, in the above conventional fuel tank,
When the fuel remains in the tank body 1, the upper space in the tank body 1 and the upper space in the filler tube 5 are completely separated from each other. When the filler cap (not shown) is removed in this state, the liquid level in the filler tube 5 rises due to the pressure of the evaporating gas in the upper part of the tank body 1, and if fuel refueling is attempted in this state, refueling work will be performed. It causes a problem that it becomes difficult.

Therefore, the present invention can surely prevent the sticking of the over-fueling prevention valve without increasing the size and weight of the valve, and at the same time, even if the temperature in the tank body rises, the temperature becomes normal. The purpose of the present invention is to provide a fuel tank that can be refueled as easily as at times.

[0009]

As a means for solving the above-mentioned problems, the invention of claim 1 provides a filler tube extending from a tank body, and a filler tube provided at an upper end of the filler tube, and A shutter that opens by insertion, a vent tube that communicates the upper space in the tank body with the canister, and an end portion of this vent tube that faces the tank body, and when the liquid level in the tank body exceeds the set height A venting valve for closing the end of the vent tube, and a vent cut valve interposed in the conduit of the vent tube for opening and closing the conduit of the vent tube in conjunction with the opening and closing operation of the shutter. In the fuel tank, the space between the supercharging prevention valve and the vent cut valve in the vent tube and the upper space in the filler tube. And an orifice communicating and.

Further, according to the invention of claim 2, the operating rod of the vent cut valve penetrates the side wall of the filler tube, and the orifice is formed around the through hole of the side wall.

According to the third aspect of the invention, a seal structure is provided for closing the orifice in conjunction with the opening operation of the shutter.

According to a fourth aspect of the present invention, a filler tube extending from the tank main body, a shutter provided at an upper end of the filler tube and opened by inserting a fuel filling gun, an upper space in the tank main body and a canister are communicated with each other. A vent tube, a superlubrication prevention valve that is provided at the end of the vent tube facing the tank body, and that closes the end of the vent tube when the liquid level in the tank body exceeds a set height; In a fuel tank equipped with a vent cut valve which is interposed in the middle of the pipe line and which opens and closes the pipe line of the vent tube in conjunction with the opening and closing operation of the shutter, A communication hole that connects the space between the filler tube and the upper space inside the filler tube is provided. A check valve that allows the flow of gas to the vent tube from and attached to a relief valve for releasing the gas from the vent tube to the filler tube when the gas pressure in the tank body becomes higher than the set pressure.

[0013]

According to the first aspect of the present invention, even if the vent cut valve blocks the end of the vent tube during fuel refueling and then the vent cut valve blocks the middle of the vent tube, the superfuel refueling inside the vent tube is prevented. The space between the prevention valve and the vent cut valve communicates with the upper space in the filler tube through the orifice, so when the liquid level in the tank body drops, the vent cut valve will block the vent tube. It will never be left alone. Also,
When the gas pressure in the upper part of the tank body rises due to the temperature rise of the tank body except when refueling, the gas pressure escapes through the orifice into the space above the filler tube, so even if the filler cap is opened in this state, the filler tube The liquid level inside does not rise significantly.

According to the second aspect of the present invention, the number of holes formed in the filler tube is reduced and a gap is formed around the operating rod, so that the sliding resistance of the operating rod is reduced.

According to the third aspect of the invention, when fuel is supplied from the filler tube, the seal structure closes the orifice in association with the opening operation of the shutter, and the filler tube and the vent tube do not communicate with each other. For this reason, the evaporated fuel gas in the tank body will not be discharged from the upper portion of the filler tube to the outside of the vehicle through the orifice at the time of refueling.

According to the fourth aspect of the present invention, even if the vent cut valve blocks the end of the vent tube at the time of refueling the fuel and the vent cut valve blocks the midway of the vent tube, the reverse hole provided in the communication hole is provided. Since the stop valve allows the gas to flow from the filler tube to the vent tube, the super-oil refueling prevention valve does not keep the vent tube closed. Further, at the time of refueling, since the communication hole is closed by the check valve and the relief valve, the evaporated fuel gas in the tank body is not discharged from the upper portion of the filler tube to the outside of the vehicle. Furthermore, when the gas pressure in the upper part of the tank body rises above the set pressure due to the temperature rise of the tank body, the gas pressure opens the relief valve, and the gas in the tank body flows into the upper space of the filler tube through the communication hole. To do. Therefore, even if the filler cap is opened in this state, the liquid level in the filler tube does not rise significantly.

[0017]

Embodiments of the present invention will now be described with reference to FIGS. In the following, the same parts as those of the conventional one shown in FIG.

First, an embodiment corresponding to claims 1, 2 and 3 will be described with reference to FIG.

In the drawings, 1 is a tank main body of a fuel tank according to the present invention, and 5 is attached to a side wall of the tank main body 1 from the bottom inside the tank main body 1 toward the upper outside of the tank main body 1. The extending filler tubes 3 are attached to the upper wall of the tank body 1 and are vent tubes that connect the upper space of the tank body 1 and the canister 2 to each other. Further, 9 indicates the vaporized fuel gas in the tank body 1 in the canister 2 during normal use other than refueling.
It is an evaporative tube that guides to. The evaporation tube 9 is attached to a position higher than the vent tube 3 on the upper wall of the tank body 1 so as to connect the upper space in the tank body 1 with the middle of the conduit of the vent tube 3. .

The filler tube 5 has an upper end
A substantially V-shaped shutter 8 for opening and closing the hinge is attached, and the shutter 8 is normally urged by a spring in a direction to close the filler tube 5 (spring means is not shown), and the fuel refueling gun 6 is attached to the filler tube. When it is inserted in 5, the fuel gun 6 pushes it open.

Further, the vent tube 3 is provided with a super-lubrication prevention valve 4 at the end facing the inside of the tank main body 1, and when the liquid level in the tank main body 1 exceeds a set height, the super-lubrication prevention is performed. The valve 4 closes the end of the vent tube 3 to shut off the electrical connection between the tank body 1 and the canister 2. And further vent tube 3
A vent cut valve 7 for closing the pipe is provided in the middle of the pipe when the fuel is not being refueled. The vent cut valve 7 is attached and fixed to the upper side wall of the filler tube 5.

The vent cut valve 7 is connected to the conduit 3a of the vent tube 3 on the tank body 1 side.
0, a second chamber 11 communicating with the conduit 3b on the canister 2 side of the tube 3, and a third chamber 12 communicating with the evaporation tube 9, and the first chamber 10, the second chamber 11, and the second chamber The chamber 11 and the third chamber 12 communicate with each other through passages 13 and 14, respectively. The second chamber 11 accommodates the valve body 15 that is spring-biased (spring means is not shown) in the direction of closing the passages 13 of the first chamber 10 and the second chamber 11, and in a normal state. , The valve body 15 closes the passage 13 of the first chamber 10 and the second chamber 11, and
The passages 14 of the chamber 11 and the third chamber 12 are opened. In addition, the valve body 15 includes a vent cut valve 7
Of the casing 16 and the operating rod 17 penetrating the upper end side wall of the filler tube 5 are integrally extended, and when the shutter 8 of the filler tube 5 is opened, the shutter 8 pushes the operating rod 17 and the first chamber 10 and second chamber 11
Open the passage 13 of the second chamber 11 and the passage 14 of the third chamber 12
Is designed to be blocked.

Here, the casing 16 through which the operating rod 17 penetrates and the through holes 18 and 19 of the filler tube 5 are
The diameter of the operating rod 17 is slightly larger than the diameter of the operating rod 17 so as to form a predetermined gap 20 with the operating rod 17, and the annular gap 20 thus formed serves as an orifice in the present invention. That is, the gap 20 communicates with the space between the overfilling prevention valve 4 and the vent cut valve 7 of the vent tube 3 and the upper space of the filler tube 5.

Further, a seal ring 21 is fixed to the outer peripheral area of the contact portion of the wall surface 8a of the shutter 8 with the operating rod 17, and when the shutter 8 is completely pushed open by the fuel refueling gun 6. The seal ring 21 is in close contact with the inner wall of the filler tube 5, and the wall surface 8 a of the shutter 8
The seal ring 21 closes the gap 20 as an orifice. Therefore, the seal ring 21 together with the wall surface 8a of the shutter 8 is defined by claim 3.
The seal structure in the invention is constituted.

Reference numeral 22 in the drawing denotes a roll-over valve attached to the end of the evaporation tube 9 facing the inside of the tank body 1, and reference numeral 23 denotes a check valve interposed in the conduit of the evaporation tube 9. is there.

With the above-described structure, when refueling the fuel, the filler cap (not shown) at the upper end of the filler tube 5 is removed, and the fuel refueling gun 6 is inserted into the same tube 5. 8, the shutter 8 pushes open the operating rod 17 of the vent cut valve 7. Then, the vent cut valve 7, which has been connecting the evaporation tube 9 and the conduit 3b of the vent tube 3 until now, connects the conduits 3a and 3b of the vent tube 3 to each other, and the refueling is started in this state. Then, the evaporated fuel gas in the tank body 1 is introduced into the canister 2 through the vent tube 3. At this time, the vaporized fuel gas in the tank body 1 flows into the vent cut valve 7 from the pipe 3a, but the gap 20 as an orifice that connects the first chamber 10 of the vent cut valve 7 and the filler tube 5 has a seal ring 21. Since it is closed by the shutter 8, the evaporated fuel gas in the tank body 1 will not be discharged from the vent tube 3 through the filler tube 5 directly to the outside of the vehicle. Further, at this time, even if the seal ring 21 and the inner wall of the filler tube 5 are not in close contact with each other, since the gap 20 is originally a minute one (orifice), a large amount of fuel vapor gas flows into the filler tube 5. There is nothing to do.

When refueling continues and the liquid level in the tank body 1 becomes higher than the set height, the overfilling prevention valve 4 closes the end of the vent tube 3 and the tank body 1 above that level is closed.
The flow of fuel into the interior stops. Therefore, if refueling continues after this, the liquid level of the filler tube 5 rises and the rise is sensed by the auto stop sensor of the fuel refueling gun 6, and the refueling of fuel is automatically stopped.

Further, when the shutter 8 is closed while the fuel is fully filled in this way, the super-oil refueling prevention valve 4 and the vent cut valve 7 close the vent tube 3. At this time, however, the vent tube 3 is closed. Lubrication prevention valve 4
Since the space between the vent cut valve 7 and the space above the filler tube 5 communicates with the space above the filler tube 5 through the gap 20 as an orifice, even if the liquid level in the tank body 1 subsequently drops, There is no negative pressure in the space and therefore no sticking of the overfill protection valve 4.

Furthermore, even if the temperature in the tank body 1 rises due to long-term operation or the like and the gas pressure in the tank body 1 rises, this gas pressure passes through the vent tube 3 and the gap 20 as the orifice. Since it gradually escapes into the upper space of the filler tube 5, the liquid level of the filler tube 5 does not rise sharply even if the filler cap is removed in this state. Therefore, the refueling work can be easily performed as in the normal state.

Further, in this fuel tank, since the orifice is formed around the through hole 18 through which the operating rod 17 penetrates, the number of holes in the filler tube 5 is reduced, and the manufacturing cost can be reduced. Has the advantage that the sliding resistance of the operating rod 17 is reduced, and thus the operating rod 17 can be operated smoothly.

In the above embodiment, the seal ring 21 for closing the gap 20 as the orifice is attached to the wall surface 8a of the shutter 8. However, as shown in FIG. The seal ring 24 may be fixed to the outer periphery so as to close the gap 20 when the actuating rod 17 is retracted, and the orifice that connects the vent tube 3 and the filler tube 5 is also provided in the gap 20 around the through hole 18. Instead, it can be provided separately.

Next, an embodiment of the invention of claim 4 will be described with reference to FIG. The same parts as those shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

This fuel tank has the same basic structure as the filler tube 5, the vent tube 3, the vent cut valve 7 and the like shown in FIG. 1, but the first chamber 10 of the vent cut valve 7 and the filler are The upper space of the tube 5 communicates with the communication holes 25 and 26, the communication hole 25 is opened and closed by the check valve 27, and the communication hole 26 is opened and closed by the relief valve 28. .

The check valve 27 is provided with a seat 29a of the valve body 29 on the side of the first chamber 10 and is operated while the pressure in the first chamber 10 is higher than the pressure in the upper space in the filler tube 5. When the seat 29a closes the communication hole 25 and the pressure on the filler tube 5 side becomes larger than the pressure on the first chamber side 10, the communication hole 25 is opened to allow the gas to flow from the filler tube 5 to the vent tube 3. It is like this.

The relief valve 28 is provided with a valve body 30 that opens and closes the communication hole 26 from the filler tube 5 side, and a spring 31 that urges the valve body 30 in the closing direction. The valve body 30 opens the communication hole 26 and opens the vent tube 3 only when the pressure exceeds the set pressure (accurately, when the pressure difference between the first chamber 10 and the filler tube 5 exceeds the set value). The gas is allowed to flow from the filler tube 5 to the filler tube 5.

Since this fuel tank is constructed as described above, when the fuel refueling gun 6 is inserted into the filler tube 5 during refueling, the vent cut valve 7 opens the vent tube 3 and starts refueling in this state. The evaporated fuel gas in the tank body 1 is guided to the canister 2 through the vent tube 3. At this time, since the pressure in the first chamber 10 of the vent cut valve 7 is slightly higher than the pressure in the filler tube 5, the check valve 27 and the relief valve 28 are connected to the communication holes 25 and 26, respectively. Is blocked. Therefore, at this time, the evaporated fuel gas in the tank body 1 does not flow from the vent tube 3 into the filler tube 5.

When the fuel refueling gun 6 is pulled out from the filler tube 5 in a state where the tank main body 1 is completely filled with fuel, the shutter 8 is closed and the over-fueling prevention valve 4 and the vent cut valve 7 are connected to the vent tube 3 Is closed. However, since the check valve 27 and the relief valve 28 are provided in the communication holes 25 and 26 that connect the first chamber 10 and the filler tube 5, the liquid level in the tank body 1 is increased by the use of fuel. If it drops, check valve 2
7 opens and the filler tube 5 to the vent tube 3
When gas flows into the (pipe 3a), the sticking of the supercharging prevention valve 4 is prevented, and further, the gas pressure in the tank body 1 rises above the set pressure due to the temperature rise of the tank body 1. The relief valve 28 opens to allow the gas in the tank body 1 to escape into the filler tube 5,
This will prevent the liquid level in the filler tube 5 from rising rapidly.

In the present invention, the communication holes 25, 2
It is possible to arbitrarily set the numbers and shapes of the six, the check valve 27, the relief valve 28, and the like.

[0039]

As described above, according to the first aspect of the present invention, the orifice for communicating the space between the supercharging oil prevention valve and the vent cut valve in the vent tube and the upper space in the filler tube is provided. Even if the prevention valve and the vent cut valve block the conduit of the vent tube, the gas in the upper space of the filler tube is gradually introduced into the space between the supercharging prevention valve and the vent cut valve in the vent tube. Therefore, the sticking of the valve can be reliably prevented without increasing the size and weight of the over-fueling prevention valve. In addition, when the gas pressure in the upper part of the tank main body rises due to the temperature rise of the tank main body except when refueling, the gas pressure can be released to the upper space of the filler tube through the orifice. Even if the filler cap is opened, the liquid level in the filler tube does not rise significantly, and therefore, even when the temperature in the tank body rises, it is possible to perform the refueling work as easily as at normal temperature. Also,
Since the vent tube and the filler tube are made to communicate with each other by the orifice, it is possible to prevent the vaporized fuel gas in the tank body from flowing into the filler tube from the vent tube during fuel refueling.

According to the second aspect of the present invention, the actuation rod of the vent cut valve penetrates the side wall of the filler tube, and the periphery of the through hole of the side wall is the orifice for communicating the vent tube and the filler tube. In addition to reducing the number of holes to be drilled, the number of man-hours required for manufacturing is reduced, and the sliding resistance of the operating rod with respect to the vent tube is reduced to enable smooth operation of the vent cut valve.

According to a third aspect of the present invention, a seal structure for closing the orifice in association with the opening operation of the shutter is provided.
Since the orifice is closed by the seal structure during fuel refueling, it is possible to reliably prevent the evaporated fuel gas in the tank body from passing through the orifice and being discharged from the upper portion of the filler tube to the outside of the vehicle during fuel refueling.

According to a fourth aspect of the present invention, a communication hole is provided which connects the space between the supercharging oil prevention valve and the vent cut valve in the vent tube and the upper space in the filler tube, and the communication hole is filled with the filler tube. A check valve that allows gas to flow from the vent tube to the vent tube, and a relief valve that allows gas to escape from the vent tube to the filler tube when the gas pressure in the tank body exceeds the set pressure. By opening the orifice with the relief valve, the stick of the over-fueling prevention valve and the liquid level rise of the filler tube are reliably prevented, and at the time of fueling, the check valve and the relief valve close the communication hole to close the tank body. It is possible to reliably prevent the vaporized fuel gas of 1 from being discharged from the filler tube to the outside of the vehicle.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of the invention of claims 1, 2 and 3.

FIG. 2 is a schematic sectional view showing another embodiment of the present invention.

FIG. 3 is a schematic sectional view showing an embodiment of the invention of claim 4;

FIG. 4 is a schematic sectional view showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tank main body, 2 ... Canister, 3 ... Vent tube, 4 ... Super oil refueling prevention valve, 5 ... Filler tube, 6 ... Fuel refueling gun, 7 ... Vent cut valve, 8 ... Shutter, 17 ... Operating rod, 20 ... Gap (Orifice), 21 ... Seal ring (seal structure), 25, 26 ... Communication hole, 27 ... Check valve, 28 ... Relief valve.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F02M 25/08 H

Claims (4)

[Claims] 1. A filler tube extending from the tank main body, a shutter provided at an upper end of the filler tube and opened by inserting a fuel refueling gun, and a vent tube communicating between an upper space in the tank main body and a canister. This vent tube is provided at the end facing the inside of the tank body, and a superlubrication prevention valve that closes the end of the vent tube when the liquid level in the tank body exceeds a set height, and a midway of the vent tube In a fuel tank provided with a vent cut valve that opens and closes the conduit of the vent tube in conjunction with the opening and closing operation of the shutter, a space between the supercharging oil prevention valve and the vent cut valve in the vent tube. A fuel tank having an orifice communicating with the upper space in the filler tube. 2. A vent cut valve operating rod is pierced through a side wall of a filler tube, and the orifice is formed around the through hole of the side wall.
Fuel tank described 3. The fuel tank according to claim 1, further comprising a seal structure for closing the orifice in association with the opening operation of the shutter. 4. A filler tube extending from the tank body, a shutter provided at an upper end of the filler tube and opened by inserting a fuel refueling gun, and a vent tube for communicating an upper space in the tank body with a canister.
This vent tube is provided at the end facing the inside of the tank body, and a superlubrication prevention valve that closes the end of the vent tube when the liquid level in the tank body exceeds a set height, and a midway of the vent tube In a fuel tank provided with a vent cut valve that opens and closes the conduit of the vent tube in conjunction with the opening and closing operation of the shutter, a space between the supercharging oil prevention valve and the vent cut valve in the vent tube. , A communication hole that communicates with the upper space in the filler tube is provided, and in this communication hole, a check valve that allows the flow of gas from the filler tube to the vent tube, and the gas pressure in the tank main body exceeds the set pressure. A fuel tank that is equipped with a relief valve that allows gas to escape from the vent tube to the filler tube when it becomes exhausted.