JP3452103B2 - Evaporative fuel processing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention prevents the evaporative fuel generated in a fuel tank during parking or refueling from being adsorbed, released during engine operation, and burned to prevent the evaporative fuel from being released into the atmosphere. The present invention relates to an evaporated fuel processing device.

[0002]

2. Description of the Related Art In a fuel system of a vehicle engine, gasoline vapor generated in a fuel tank (hereinafter referred to as "evaporated fuel") is released into the atmosphere during parking, or a filler neck of a fuel tank is filled during refueling. An evaporative fuel treatment device is provided to prevent the fuel from being released from the fuel filler into the atmosphere. As shown in FIG. 1, the evaporated fuel processing device 1 is
The evaporated fuel generated in the fuel tank 2 is introduced into the canister 10 through the leveling valve 4, the vent hose 5, the rollover valve 6, and the hole (inlet of evaporated fuel) 10a,
The adsorbent (activated carbon) 11 filled in the canister 10 is adsorbed. Fuel component (H
The gas (air) from which C) has been removed is discharged to the atmosphere through the atmosphere opening port 10c of the canister 10, the atmosphere opening passage 14, the leak check switching valve 15, and the air filter 16.

Then, the evaporated fuel processing apparatus 1 introduces the negative pressure in the intake manifold into the canister 10 through the leak check switching valve 12, the purge pipe 13 and the hole 10b (evaporated fuel outlet) when the engine is operating. ,
Atmosphere (purging air) is sucked through the leak check switching valve 15 and the air filter 16 from the atmosphere opening passage 14 connected to the atmosphere opening port 10c of the canister 10, and the evaporated fuel adsorbed by the adsorbent 11 is separated (purged). ) And is led to the engine through the purge pipe 13 and the switching valve 12 and burned. Thereby, the adsorbent 11 of the canister 10
Prepares for the adsorption of the fuel evaporative fuel at the next parking or refueling by recovering the adsorption ability.

The fuel tank 2 and the rollover valve 6
A two-way valve 7 is provided between and to open the leveling valve 4 when the internal pressure of the fuel tank 2 rises due to the evaporated fuel when the leveling valve 4 is closed to allow the evaporated fuel to escape to the canister 10 and reduce the tank internal pressure. ing. When a large amount of evaporated fuel is generated and an amount of evaporated fuel that exceeds the adsorption capacity of the canister flows into the canister, the evaporated fuel is released into the atmosphere. In order to prevent this, the device disclosed in Japanese Utility Model Laid-Open No. 3-1256 has a valve provided in the vent port of the canister that responds to the internal pressure of the fuel tank, and when the inside of the fuel tank reaches a predetermined positive pressure. This valve is closed to close the canister vent port. This prevents the release of the evaporated fuel when a large amount of evaporated fuel is generated without using a large capacity canister.

By the way, the above-described evaporative fuel processing apparatus is used to check for a leak in the fuel system (a hole is formed in the filler neck 2, the vent hose 5 , the purge pipe 13, etc., and evaporative fuel is released to the atmosphere). Leak check switching valves (on / off solenoid valves) 12 and 15 are attached to the pipe 13 and the atmosphere opening port 10c of the canister 10. To check the leak of the fuel system, a pressure gauge 17 is connected to the fuel tank 2, the switching valve 12 is opened, and the switching valve 15 is closed to apply a negative pressure of the engine to the fuel vapor system. Next, the switching valve 12
The pressure gauge 17 detects a change in pressure after the valve is closed to detect whether or not there is a leak in the fuel system.

In the evaporated fuel processing device having such a failure diagnosis function, a large positive pressure or negative pressure may be formed in the fuel tank when the switching valve is closed. In order to avoid this, the evaporative fuel treatment device disclosed in Japanese Patent Publication No. 4-505491 has a pressure-responsive type arranged on the canister side of a switching valve for failure diagnosis provided on the vent port side of the canister. It has a protective valve and is opened to open the protective valve as needed to optimize the internal pressure of the fuel tank.

In connection with the diagnosis of fuel system leakage, the switching valve 15 is required to be airtight when it is closed. On the other hand, the purge air flowing into the switching valve 15 may contain mud and dust. If the mud or dust adheres to the valve body or the valve seat of the switching valve 15, the airtightness of the switching valve 15 when the valve is closed is reduced. Therefore, the atmosphere open passage 14
It is conceivable to provide an air filter 16 on the atmosphere open side of the switching valve 15 to remove mud and dust in the atmosphere.

[0008]

However, when the air filter 16 is connected to the atmosphere opening port 10c of the canister 10 in the fuel vapor processing apparatus having the above-described structure, the air from the fuel tank 2 to the atmosphere passing through the canister 10 and the air filter 16 is changed. The pressure loss becomes large, the evaporated fuel generated in the fuel tank 2 at the time of refueling hardly flows into the canister 10 from the fuel tank 2, and the refuelability deteriorates. Therefore, in order to reduce the pressure loss and have the effect of the filter 16, it is necessary to upsize the air filter 16.

In order to reduce the pressure loss from the fuel tank 2 to the atmosphere passing through the canister 10 and the air filter 16, the vent hose 5 connecting the fuel tank 2 and the canister 10 must be thick and the vent hose 5 must be long. It is preferable to shorten the length. In this case, the canister 10 is arranged near the fuel tank 2, and therefore the air filter 16 is arranged near the fuel tank.

However, if the air filter 16 is made large in order to have a filter effect, the degree of freedom of the installation place becomes low. Especially, the space near the fuel tank 2 has a small space and it is difficult to install the air filter 16. . There is also a problem that it is difficult to dispose the atmosphere-side opening end of the air filter 16 of the atmosphere opening passage 14 at a position where mud or the like does not hit.

With respect to the attachment of an air filter to the switching valve, Japanese Patent Publication No. 5-34513 discloses a device provided with a filter downstream of a solenoid valve provided in a vent port of a canister. . However, this solenoid valve merely responds to refueling and engine operation, and is not used for failure diagnosis of the evaporated fuel processing device.

The device disclosed in Japanese Patent Laid-Open No. 4-505491 has no air filter at the vent port of the canister, and does not intend to purify the purge air. Therefore, this prior art does not suggest any new problems and solutions associated with the arrangement of the air filter device. The protective valve of this device does not respond to refueling, and its installation location is limited to the upstream side of the switching valve.

The present invention has been made in view of the above points, and aims to improve refueling performance, downsize an air filter connected to the atmosphere opening side of a canister, and increase the degree of freedom of installation location. It is an object of the present invention to provide an evaporated fuel processing device configured to do so.

[0014]

To achieve the above object, according to the present invention, in claim 1, a canister for adsorbing evaporated fuel, an on-off valve provided in an atmosphere opening passage of the canister, and comprising an air filter disposed on the downstream air opening side than the on-off valve of the atmosphere open passage, and the atmosphere passage provided in the atmosphere opening side of the canister, the opening and closing means for opening and closing the air passage, said opening and closing means The above
Only when the internal pressure of the atmosphere passage is higher than the atmospheric pressure
It is configured to open a passage .

In the invention of claim 1, the inventions of claims 2 and 3 are described.
As described above, it is preferable to provide the atmosphere passage between the opening / closing valve of the atmosphere opening passage and the air filter or on the upstream side of the opening / closing valve of the atmosphere opening passage. According to the invention of claim 1 and its preferred embodiment, a one-way valve that opens the atmosphere passage or the reed valve that performs a similar operation when the atmosphere release passage or the canister becomes a positive pressure due to the pressure generated by refueling. It is preferable to configure the opening / closing means.

[0016] In the invention of claim 1, preferably, the atmosphere passage is a fuel filler base or a filler.
It is configured to open for communication in the vicinity of the filler opening of the neck , or
It is configured to directly communicate with the canister.

Connect the atmosphere passage to the fuel filler base.
In the preferred embodiment obtained by passing opening, preferably, the switching means is provided so as to be opened and closed to the fuel filler base, is composed of a fuel filler lid for sealing the fuel base. Alternatively, the opening / closing means
Is installed on the fuel filler lid and
In front of the atmosphere release passage when the fuel filler lid is closed
Seal the open end that opens to the fuel filler base.
It is composed of a lid. In a preferred aspect in which the atmosphere passage is open for communication in the vicinity of the filler neck ,
When the opening / closing means is attached to the fuel filler port,
A filler key that closes the open end of the atmosphere passage that opens to the oil port.
It is composed of caps.

In claim 4, the evaporated fuel processing device is
The canister according to claim 1, an on-off valve, an air filter,
In addition to the atmosphere passage and the opening / closing means, a refueling determination means for determining that refueling is in progress is provided, and the opening / closing means is provided
When it is determined by the oil determination means that refueling is in progress,
If the air passage is opened and it is determined that it is not during refueling, the above
It is configured to close the atmosphere passage.

According to a fifth aspect of the invention, the opening / closing means comprises a shutter for opening / closing the opening end of the atmosphere passage opening to the fuel supply port.

The shutter is driven by the filler cap when the filler cap is attached to close the opening end of the atmosphere passage, and a valve that opens and closes a refueling gun insertion hole of a restrictor provided at the refueling port during refueling. It is configured to be driven to open the opening end. Contract
In Claim 6, the evaporative fuel treatment apparatus includes pressure detection means for detecting pressure upstream of the on-off valve , and the evaporative fuel treatment apparatus of the evaporative fuel treatment apparatus is based on a change in pressure detected when the on-off valve is closed. The configuration is such that a failure is determined.

According to the first aspect of the present invention, the fuel component of the evaporated fuel generated in the fuel tank at the time of refueling is removed by the canister, and the gas (air) flows from the atmosphere open passage to the atmosphere passage.
It At the time of refueling, the internal pressure of the atmosphere passage becomes higher than the atmospheric pressure.
Since the opening / closing means opens the atmosphere passage, gas is released from the atmosphere passage to the atmosphere. As a result, the evaporated fuel generated during refueling easily flows into the canister from the fuel tank, and refueling performance is improved. During the fuel system leak check, the on-off valve is closed, the opening / closing means is closed, and the atmosphere opening port of the canister is closed.

The atmosphere passage should be close to the filler neck oil filler port.
In the preferred mode in which the communication is opened, the gas flowing out from the canister to the atmosphere opening passage at the time of refueling flows from the atmosphere passage to the vicinity of the filler neck fuel filler port and is discharged to the atmosphere.

In claim 4, the opening / closing means is provided except when refueling.
The atmosphere passage is closed, but when refueling, the atmosphere passage is opened to release the gas flowing from the canister to the atmosphere release passage to the atmosphere.
It According to the fifth aspect, the gas flowing from the canister to the atmosphere opening passage at the time of refueling flows from the atmosphere passage to the fuel filler base in which the fuel filler lid is opened, and is released to the atmosphere. The fuel filler base is
It is sealed when the fuel filler lid is closed.
According to the sixth aspect, the failure of the evaporated fuel processing device is determined based on the change in the pressure detected by the pressure detecting means.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to Examples 1 to 10. In the attached drawings, the same members as those shown in FIG. 1 are designated by the same reference numerals. (Embodiment 1) In the evaporated fuel processing device shown in FIG. 2, a leak check switching valve (ON / OFF switch) is provided in the middle of an atmosphere opening passage 14 connected to an atmosphere opening port 10c of a canister 10.
An off solenoid valve) 15 is connected, and an air filter 16 is provided at the open end of the atmosphere opening passage 14 on the atmosphere side. A three-way joint 18 is connected to the atmosphere opening passage 14 between the switching valve 15 and the air filter 16, and a one-way valve 19 is connected to a port 18a of the three-way joint 18 that opens to the atmosphere. An atmosphere passage is provided inside the three-way joint 18 and the one-way valve 19.
The switching valve 15 is an on / off solenoid valve as described above, and is normally deenergized and opened, and is energized and closed during a leak check.

The one-way valve 19 is connected to the atmosphere open passage 1
When the internal pressure of 4 is higher than atmospheric pressure, that is, when the pressure is positive, the valve is opened to open the atmosphere passage, and the pressure is released from the atmosphere release passage 14 side to the atmosphere side. The one-way valve 19 is configured to open with an extremely small positive pressure generated during refueling, and the valve body 19a is formed of a lightweight float, for example, a synthetic resin member such as plastic. The valve body 19a is placed on the valve seat 19b and can be closed by its own weight.
The opening c is opened above the valve body 19a. As in the case of FIG. 1, the canister 10 has an evaporative fuel inlet 10a in a fuel tank through a vent hose, a rollover valve, and a leveling valve, and an evaporative fuel outlet 10b in a purge pipe.
Each is connected to an intake manifold of the engine via a leak check switching valve.

The operation will be described below. The switching valve 15 is normally opened with the solenoid deenergized, and the one-way valve 19 is closed by the float 19a closing the valve seat 19b by its own weight. When the fuel tank is refueled, a large amount of evaporated fuel is generated, and this evaporated fuel flows into the canister 10 from the inlet 10a of the canister 10, and the fuel component (hydrocarbon (HC)) is adsorbed on the adsorbent 11. Is adsorbed on. The gas (air) from which the fuel component has been removed by the canister 10 flows from the atmosphere opening port 10c through the switching valve 15 into the atmosphere opening passage 14.

The pressure of the gas flowing into the atmosphere opening passage 14 is slightly higher than the atmospheric pressure, and therefore the atmosphere opening passage 1
The internal pressure of 4 becomes a positive pressure. The air filter 16 connected to the atmosphere-side open end of the atmosphere opening passage 14 has a large resistance, and therefore the gas in the atmosphere opening passage 14 is not mixed with the three-way joint 1
One-way valve with low resistance from port 18a of 8
Pour into 9. The gas flowing into the one-way valve 19 pushes up the lightweight float 19a to open the one-way valve 19 and is discharged to the atmosphere from the atmosphere port 19c. That is, at the time of refueling, the flow of gas flows toward the one-way valve 19 having a small resistance, and the resistance of the air filter 16 becomes irrelevant. As a result, refuelability is improved.

When a negative pressure acts on the canister 10 during engine operation, the atmosphere opening port 10c and the atmosphere opening passage 14 become negative pressure, and the float 19a of the one-way valve 19 is pressed against the valve seat 19b by the atmospheric pressure to cause the one-way valve 1 to move.
9 is closed. As a result, the atmosphere (purge air) is sucked from the air filter 16. This makes the canister 1
At 0, clean air is introduced. Further, when the switching valve 15 is closed when checking the leakage of the fuel system, the canister atmosphere opening port 10c side of the atmosphere introducing passage 14 is sealed.

(Embodiment 2) In FIG. 3, the evaporated fuel processing apparatus is provided with a reed valve 20 in the atmosphere open passage 14 of the canister 10 in place of the float type one-way valve 19 of FIG. An atmosphere passage is provided inside the reed valve 20. This reed valve 20
The valve body 20a is formed of, for example, a soft rubber plate, and the float 19 of the one-way valve 19 of FIG.
Like a, the valve can be opened by being pushed up from the valve seat 20b by an extremely small positive pressure in the atmosphere opening passage 14.

(Embodiment 3) In FIG. 4, the evaporated fuel processing apparatus uses a diaphragm type one-way valve 33 in place of the float type one-way valve 19 of FIG. The one-way valve 33 has a diaphragm-like internal structure, and a valve body 33c and a spring 33d are attached to a port 33b for opening the atmosphere, which is provided in the middle of the atmosphere passage 33a.
The valve is closed by pressure contact with. The valve opening pressure is set to an extremely low value.
It is said that the maximum is about 20 mm Ag at liter / minute.

The one-way valve 33 has a passage 33a.
When the internal pressure of the valve is positive, the valve element 33c opens against the spring force of the spring 33d, and when it is negative, the spring 33d is opened.
The valve is closed by the spring force and atmospheric pressure. The one-way valve 33 is connected to the atmosphere opening passage 14 on the upstream side of the switching valve 15, and the port 3 provided in the case.
3e is open to the atmosphere.

When the atmosphere flows out from the canister 10 into the atmosphere opening passage 14 at the time of refueling and the internal pressure of the atmosphere opening passage 14 becomes a positive pressure, the one-way valve 33 opens and most of the atmosphere flowing into the atmosphere passage 14 is As shown by the arrow, it is released from the port 33e of the one-way valve 33 to the atmosphere. Since the pressure loss at the one-way valve 33 is small, even if the pressure loss at the switching valve 15 and the air filter 16 is large, the oil supply property is improved.

When a negative pressure acts on the canister 10 during engine operation, the internal pressure of the atmosphere opening passage 14 becomes a negative pressure, and as shown in FIG. 5, the valve body 33c of the one-way valve 33 becomes a port due to the atmospheric pressure and the spring force of the spring 33d. 33b
Is closed and the valve is closed, and the atmosphere opening port 10c of the canister 10 is opened.
Seal. Therefore, a fuel system leak check system can be established, and the number of man-hours for new development of the system can be reduced.

In the first and second embodiments, the switching valve 15
A one-way valve 19 and a reed valve 20 are provided in the atmosphere opening passage 14 between the air filter 16 and the air filter 16, respectively.
If there is no problem in the airtightness at the time of leak check of the fuel system, there is no problem in disposing it on the upstream side of the switching valve 15 in the atmosphere opening passage 14 as in the third embodiment.

(Embodiment 4) In FIG. 6, the fuel vapor treatment system has a three-way joint 18 connected between the switching valve 15 and the air filter 16 to the atmosphere opening passage 14. The atmosphere port 18 a of the three-way joint 18 is connected to the filler port 3 of the filler neck 3 of the vehicle body 8 via a passage (atmosphere passage) 21.
The chamber 8a (hereinafter referred to as "fuel filler base") in which "a" is stored communicates with and opens. A seal 22 is attached to the open end of the fuel filler base 8a so that the inside of the fuel filler base 8a becomes a closed space when the fuel filler lid 8b is closed.

During refueling, the fuel filler lid 8b
Is opened, the fuel filler base 8a is opened to the atmosphere, and thus the passage 21 is opened to the atmosphere. The gas from which the fuel component has been removed by the canister 10 at the time of refueling is supplied from the atmosphere opening port 10c to the switching valve 15, the three-way joint 18,
It is guided to the fuel filler base 8a through the passage 21 and discharged to the atmosphere.

After refueling is completed, the fuel filler base 8a is sealed when the fuel filler lid 8b is closed. Therefore, air can be prevented from entering from the passage 21 when the intake negative pressure of the engine acts on the canister 10. The purge air is drawn in through the air filter 16. As described above, the atmosphere passage 21 is connected to the atmosphere opening passage 14 between the switching valve 15 and the air filter 16. At the time of fuel system leak check, the switching valve 1
Since the valve 5 is closed, the communication between the atmosphere and the canister 10 through the passage 21 is blocked by the switching valve 15, and therefore,
The provision of the passage 21 does not adversely affect the leak check.

Since the oil supply property is improved by the provision of the atmosphere passage 21, the atmosphere side 23 of the air filter 16 of the atmosphere release passage does not need to have a larger diameter than the passage 21 (inner diameter of about 15 to 20 mm). A small diameter (inner diameter of about 8 to 10 mm) is sufficient. In addition, since it does not matter if the length of the atmosphere opening passage 23 is increased, the passage 23 can be routed. Therefore, the degree of freedom in the layout of the air filter 16 is increased, and the open end of the atmosphere introduction passage 23 can be arranged at a position where it is not easily affected by mud or the like. Further, since the diameter of the atmosphere passage 21 can be reduced, the air filter 16 can be downsized.

(Embodiment 5) In FIG. 7, the evaporated fuel processing apparatus is similar to that of Embodiment 4 shown in FIG.
The third embodiment differs from the fourth embodiment in that a three-way joint 18 is connected to the atmosphere opening passage 14 between the atmosphere opening port 10c of the canister 10 and the switching valve 15. A switching valve 15 and an air filter 16 are connected to the small-diameter atmosphere opening passage 23. In this embodiment, the fuel filler base 8a is completely enclosed by the filler lid 8b and the seal 22 when the fuel filler lid 8b is closed. This prevents the atmosphere from flowing from the fuel filler base 8a into the passage 21 when the switching valve 15 is closed and the leak of the fuel system is checked. With such a structure, the switching valve 15 can be downsized, the cost can be reduced, and the flexibility of the layout of the air filter 16 can be improved.

(Embodiment 6) In FIG. 8, in the evaporative fuel processing system, a three-way switching solenoid valve 24 is connected to the atmosphere opening passage 14 between the switching valve 15 and the air filter 16, and whether or not fuel is being supplied. A determination means 25 for determining whether or not is provided, and the three-way switching solenoid valve 24 is energized at the time of refueling to release the atmospheric air port 24a.
Is opened so that the gas flowing into the atmosphere opening passage 14 from the atmosphere opening port 10c of the canister 10 is released to the atmosphere. Also in this embodiment, the atmosphere opening passage 23 connecting the air filter 16 can be made small in diameter and extended, and the air filter 16 is arranged and the opening end of the atmosphere opening passage 2 is arranged at a position where the influence of mud or the like is small. be able to.

The discriminating means 25 is, for example, a switch driven by opening and closing the fuel filler lid (FIG. 6). This switch 25 has a movable contact 25a when the fuel filler lid is opened, that is, when refueling.
It is connected to b and 25c and turned on, and energizes the switching solenoid valve 24 to open the atmospheric port 24a. On the other hand, when the fuel filler lid is closed, that is, when refueling is not performed, the switch is turned off to deactivate the three-way switching solenoid valve 24 and close the atmospheric port 24a. The switch 25 may be turned on when the filler cap of the filler neck is opened or when the fuel gun is inserted into the fuel filler port.

(Embodiment 7) Referring to FIG. 9, the evaporative fuel processing system includes an atmosphere opening port 10c of a canister 10 and a switching valve 1.
The three-way joint 18 is connected to the atmosphere opening passage 14 between the
The atmosphere port 18a is opened through the atmosphere passage 27 to the fuel filler base 8a that accommodates the oil supply port 3a of the filler neck 3 of the vehicle body 8, and the fuel filler lid 8b is opposed to the opening end 27a of the passage 27 and the spring is opened. A cap (valve) 29 is provided via 28. When refueling, that is, when the fuel filler lid 8b is opened as indicated by the chain double-dashed line, the passage 2
The open end 27a of the No. 7 is opened, whereby the gas flowing out from the atmosphere opening port 10c of the canister 10 to the atmosphere opening passage 14 is released to the atmosphere through the passage 27.

When the fuel filling is completed and the fuel filler lid 8b is closed as shown by the solid line, the cap 29 is opened by the spring force of the spring 28.
And the open end 27a is completely closed. Therefore, when negative pressure acts on the canister 10, air is prevented from entering from the passage 27. The purge air is sucked from the air filter 16. In addition, the open end 27 of the passage 27
When the switching valve 15 is closed when checking the leakage of the fuel system in the state where a is completely sealed, the atmosphere opening port 10c of the canister 10 is completely closed. Also in this embodiment, the air introduction passage 23 to which the air filter 16 is connected can be made small in diameter and extended.

(Embodiment 8) Referring to FIG. 10, the evaporative fuel processing system includes a three-way joint 18, a switching valve 15 and an air filter 1.
6 is different from that of the seventh embodiment shown in FIG. In this Example 8,
Even when the opening end 27a of the atmosphere passage 27 is not completely sealed, the atmosphere opening port 10c of the canister 10 can be completely closed by closing the switching valve 15. Therefore, the provision of the atmosphere passage 27 does not adversely affect the fuel system leak check.

(Embodiment 9) In FIG. 11, the evaporative fuel treatment system is similar to that of Embodiment 7 shown in FIG. 9, but the opening end 27a of the atmosphere passage 27 is provided under the refueling port 3a. The fuel filler port 3 is located above (Fig. 12).
It differs from that of Example 7 in that it is opened near the center of a. The filler neck 3 has an oil supply port 3a formed with a long screw 3b which is screwed into the filler cap 9. Further, as shown in FIG. 12, the body portion 9 of the filler cap 9 is
The a and the screw portion 9b are formed long.

The open end 27a of the passage 27 is closed by the body portion 9a of the filler cap 9 when the filler cap 9 is attached to the filler opening 3a, as shown in FIG. As a result, for example, even when the valve 3e that closes the hole 3d of the restrictor 3c provided near the fuel filler port 3a is opened when the vehicle turns, the fuel flows from the filler neck 3 to the canister 10 even if the valve 3e opens. Is prevented from flowing into. Filler cap 9 when refueling
When the gas is removed, the open end 27a of the passage 27 opens to the filler opening 3a, and the gas flowing out from the canister 10 to the atmosphere opening passage 14 passes through the passage 27 and the filler inlet 3 of the filler neck 3 is discharged.
It is released from a into the atmosphere.

(Embodiment 10) In FIG. 13, an evaporated fuel processing apparatus is provided with a valve for opening and closing a filler cap 9 and a hole of a restrictor 3c at an opening end 27a of a passage 27 which opens at a filler port 3a of a filler neck 3. It is adapted to be opened and closed by a shutter 30 driven by 3e. The filler neck 3 has a long filler opening 3a,
Further, the opening end 27a of the passage 27 opens at a position above the restrictor 3c provided in the fuel filler port 3a.

The shutter 30 is provided on the inner surface of the oil supply port 3a having the opening end 27a opened so as to be airtight and slidable in the axial direction. The hole 30a is formed in the upper portion and the projection 30b is provided in the lower end. Has been. The shutter 30 closes the opening end 27a at the lower limit position, and the hole 30a coincides with the opening end 27a at the upper limit position to open the opening end 27a to the fuel filler port 3a.

On the other hand, a protrusion 3g engageable with the protrusion 30b is provided at the base end of the valve 3e on the rotating shaft 3f side for opening and closing the hole 3d of the restrictor 3c, and the protrusion 30b is opened by the valve 3e. Is pushed up, and the shutter 30 is pushed up to the upper limit position. When the valve 3e is closed, the shutter 30 is pushed by its own weight or by the lower end 9c of the cap 9 to descend to the lower limit position. The lower end 9c of the filler cap 9 comes into contact with the upper end of the shutter 30 and locks at the lower limit position when the filler cap 9 is attached to the fuel filler port 3a, thereby preventing the shutter 30 from moving upward.

The shutter 30 is held at the lower limit position by the filler cap 9 when the filler cap 9 is attached, and closes the opening end 27a of the passage 27. As a result, the passage 27 is completely shut off from the fuel filler port 3a, and the gasoline vapor generated in the fuel filler port 3a is prevented from leaking to the atmosphere from the passage 27, the switching valve 15 and the filter 16. The valve 3e closes the hole 3d of the restrictor 3c with a spring force.

As shown in FIG. 14, the filler cap 9 is removed at the time of refueling, the refueling gun is inserted into the refueling port 3a, and the valve 3e is pushed open and rotated.
Pushes the projection 30b of the shutter 30 up to the upper limit position. As a result, the hole 30a of the shutter 30 is closed at the opening end 27a
And the gas flowing out from the canister 10 to the atmosphere opening passage 14 coincides with the passage 27.
Through the filler neck 3 to the atmosphere.

The present invention is not limited to Embodiments 1 to 10 above, but can be modified in various ways. For example, Examples 1 to 1 above
0, the atmosphere passage formed inside the three-way joint 18 and the one-way valve 19 shown in FIG.
The canister 1 through the atmosphere opening passage indicated by reference numeral 14 in FIG.
However, the atmosphere passage may be directly connected to the canister 10. Such modified examples are shown in FIGS. 15 and 17 to 2.
Shown in 1. 15 and 17 show modified examples of the first embodiment, and FIGS. 18, 19, 20 and 21 show modified examples of the fifth, seventh, ninth and tenth embodiments.

In FIG. 15, the inlet port of the one-way valve 19 is connected to the canister 10 via a short pipe 18 '.
Is connected to the vent portion 10B. Therefore, pipe 1
Atmosphere passages 18'A and 19A defined by 8'and the one-way valve 19 are in direct communication with the vent portion 10B. In FIG. 17, the one-way valve 19 has the vent portion 1
It is directly provided to 0B. That is, the valve seat 19b of the one-way valve 19 is formed in the casing of the canister 10. Further, a hole formed in the valve seat 19b (casing of the canister 10) and into which the tip of the valve body 19a is detachably fitted constitutes a part of the atmosphere passage. The one-way valve 19 shown in FIGS. 15 and 17 opens when a small positive pressure is generated in the canister 10 during refueling.

In FIGS. 18 to 21, one end of the pipe 21 or 27 that defines the atmosphere passage is directly connected to the vent portion 10B. The cross-sectional area of the atmosphere passage is larger than that of the atmosphere opening passage defined by the vent pipe 14. In the first and second embodiments, the one-way valve 19 and the reed valve 20 are connected to the atmosphere opening passage (vent pipe) 14 via the three-way joint 18, respectively, but the valves 19 and 20 are directly connected to the vent pipe 14. May be. FIG. 16 shows such a modification of the first embodiment. In FIG. 16, the valve seat 19b of the one-way valve 19 is shown.
Are formed on the peripheral wall of the vent pipe 14. Also,
A hole formed in the valve seat 19b (peripheral wall of the vent pipe 14) into which the tip of the valve element 19a is detachably fitted constitutes a part of the atmosphere passage.

[0055]

As described above, according to the present invention, in claim 1, since the air filter is provided in the atmosphere opening passage, the air flowing into the atmosphere opening passage can be cleaned by the filter, whereby the inflow atmosphere can be cleaned. Of mud and dust contained in the atmosphere,
It is possible to prevent the on-off valve from entering the inside, and thus the closing operation of the on-off valve does not become incomplete. For this reason, when the evaporated fuel leak test (fault diagnosis) is performed, the communication between the engine intake system and the canister and the communication between the canister and the atmosphere can be completely cut off, and the fault diagnosis accuracy is improved. Further, the fuel component of the evaporated fuel generated in the fuel tank at the time of refueling is removed by the canister, and gas (air) flows from the atmosphere open passage through the atmosphere passage to the opening / closing means with low resistance, and the atmosphere communication is performed.
The internal pressure of the passage becomes higher than the atmospheric pressure, and it is opened by the opening / closing means.
As a result, the evaporated fuel generated at the time of refueling easily flows into the canister from the fuel tank, and the refuelability is improved despite the provision of the air filter. Further, since it is not necessary to pass the gas flowing out of the canister through the air filter at the time of refueling, it is possible to reduce the size of the air filter, and the degree of freedom of the filter installation location is increased.

According to the second aspect, since the atmospheric passage is provided in the atmospheric opening passage between the on-off valve and the air filter, it is not necessary to directly connect the atmospheric passage to the canister, so that the structure is simplified. In claim 3, the atmosphere passage is connected to the atmosphere release passage between the on-off valve and the canister .
Therefore , at the time of refueling, the gas discharged from the canister flows into the atmosphere passage on the upstream side of the opening / closing valve, and therefore the gas can be discharged into the atmosphere without receiving the flow path resistance of the opening / closing valve and the air filter. , Refuelability is improved. Further, even if the flow path resistance of the atmosphere opening passage on the downstream side of the on-off valve is increased, the refueling property does not deteriorate. That is, the cross-sectional area of the atmosphere opening passage on the downstream side of the on-off valve can be reduced or the length thereof can be increased. For this reason, the on-off valve can be downsized, and the degree of freedom in selecting the location of the filter is increased. For example, it becomes possible to install a filter in a place where mud does not hit. Further, since it is not necessary to directly connect the atmosphere passage to the canister, the device structure is simplified.

In the invention of claim 1 , the device can be constructed at low cost by using the one-way valve or the reed valve for opening the atmosphere port to the atmosphere as the opening / closing means when the atmosphere opening passage has a positive pressure. . Claim
In the invention of item 1, the air passage is opened in the fuel filler base , or the opening / closing means is constituted by a fuel filler lid or a lid or a filler cap provided on the fuel filler lid, or the air passage is opened in the vicinity of the oil supply port. br /> allowed by Rukoto can surely prevent the entry of mud and dust into the atmosphere passage.

Further, in the invention of claim 1, the opening / closing means can be configured by using the existing fuel system constituent member by configuring the opening / closing means by the fuel filler lid or the lid or the filler cap provided on the fuel filler lid. The configuration is simple. In the invention of claim 1, the degree of freedom in constructing the atmosphere passage can be increased by directly communicating the atmosphere passage with the canister and providing the atmosphere passage independently of the atmosphere opening passage provided with the air filter. For example, the atmosphere passage can be configured so that mud and dust do not enter. According to the invention of claim 4 , it is determined that it is during refueling.
It is equipped with a refueling determination means that opens and closes to the atmosphere when refueling
While opening the passage, close the air passage when not refueling
Therefore, opening and closing of the atmosphere passage can be reliably performed.

In the fifth aspect of the invention, since the opening / closing means is constituted by the shutter, it is possible to reliably prevent the entry of mud and dust into the atmosphere passage. Further, the shutter when the filler cap is mounted to the fuel supply port by driving the filler cap closing the air passage, also, at the time of refueling, to open and close the fuel gun insertion opening formed in the restructuring Kuta provided at the filler port Since the shutter is driven by the valve to open the atmosphere passage, the opening / closing means can be driven by the existing fuel system constituent member, and the device structure is simplified.

According to the sixth aspect of the present invention, since the failure of the evaporated fuel processing device is judged based on the change in the pressure detected by the pressure detecting means, the evaporated fuel leakage can be surely judged.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a conventional evaporated fuel processing device.

FIG. 2 is a main part configuration diagram of Embodiment 1 of the evaporated fuel processing apparatus according to the present invention.

FIG. 3 is a configuration diagram of a main part of a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a main part of a third embodiment of the present invention.

5 is a diagram showing the valve closed state of FIG. 4. FIG.

FIG. 6 is a configuration diagram of a main part of a fourth embodiment of the present invention.

FIG. 7 is a configuration diagram of a main part of a fifth embodiment of the present invention.

FIG. 8 is a configuration diagram of a main part of a sixth embodiment of the present invention.

FIG. 9 is a configuration diagram of a main part of a seventh embodiment of the present invention.

FIG. 10 is a configuration diagram of a main part of an eighth embodiment of the present invention.

FIG. 11 is a configuration diagram of a main part of a ninth embodiment of the present invention.

FIG. 12 is an enlarged view of an essential part showing a state in which a filler cap is attached to the filler neck of FIG.

FIG. 13 is a configuration diagram of essential parts of Embodiment 10 of the present invention.

FIG. 14 is an explanatory diagram of FIG. 13 during refueling.

FIG. 15 is a partial view showing a modification of the first embodiment in which the atmosphere passage is directly connected to the vent portion of the canister.

FIG. 16 is a partial view showing a modification of the first embodiment in which the one-way valve is directly connected to the vent pipe.

FIG. 17 is a partial view showing a modification of the first embodiment in which the one-way valve is directly provided on the vent part.

FIG. 18 is a partial view showing a modified example of the example 5 similar to the case of FIG.

FIG. 19 is a partial view showing a modification example of Example 7 similar to the case of FIG. 15;

FIG. 20 is a partial view showing a modification example of Example 9 similar to the case of FIG. 15;

FIG. 21 is a partial view showing a modification example of the tenth embodiment similar to that of FIG. 15;

[Explanation of symbols]

1 Evaporative fuel processor 2 fuel tank 3 filler neck 3a Filling port 3b screw 3c restructuring 3d hole 3e valve 3g protrusion 4 Leveling valve 5 Vent hose 6 rollover valve 7 2-way valve 8 car body 8a Fuel filler base 8b Fuel filler lid 9 Filler cap 9a body 10 canisters 10B vent part 11 Adsorbent 12, 15 switching valve (on / off solenoid valve) 14, 23 Atmosphere open to the atmosphere 16 air filter 17 Pressure gauge 18 three-way joint 19 one-way valve 20 reed valve 21, 27 atmosphere passage 24 Three-way switching solenoid valve 25 Refueling discrimination means (switch) 28 springs 29 caps 30 shutters 30a hole 31 Protrusion 33 diaphragm one-way valve

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Kimura 5-3-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Yoichiro Ando 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation (56) References Japanese Patent Laid-Open No. 6-42412 (JP, A) Actual Development 4-42258 (JP, U) Special Table 4-505491 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F02M 25/08 F02M 37/00

Claims (6)

(57) [Claims] 1. A canister for adsorbing evaporated fuel, an opening / closing valve provided in an atmosphere opening passage of the canister, an air filter provided in an atmosphere opening side of the atmosphere opening passage downstream of the opening / closing valve, and An atmosphere passage is provided on the atmosphere open side of the canister, and an opening / closing means for opening / closing the atmosphere passage , wherein the opening / closing means has an internal pressure in the atmosphere passage higher than atmospheric pressure.
The evaporated fuel processing device is configured to open the atmosphere passage only when there is no fuel. 2. The atmosphere passage is opened and closed by the atmosphere release passage.
Characterized in that it is provided between the valve and the air filter
The evaporated fuel processing device according to claim 1. 3. The atmosphere passage is opened and closed by the atmosphere release passage.
The valve is provided on the upstream side of the valve.
The evaporated fuel processing device according to. 4. A canister for adsorbing vaporized fuel, an opening / closing valve provided in an atmosphere opening passage of the canister, and an atmosphere opening side of the atmosphere opening passage downstream of the opening / closing valve in the atmosphere opening side.
An air filter provided, an atmosphere passage provided on the atmosphere opening side of the canister, an opening / closing means for opening / closing the atmosphere passage, and a refueling determination means for determining that refueling is being performed, and the opening / closing means is Is being refueled by the refueling determination means
When it is determined that
The air passage is configured to be closed when it is determined that there is
Evaporation fuel processor characterized in that. 5. The opening / closing means is a shutter that opens and closes an opening end of an atmosphere passage that opens in the vicinity of a fuel filling port, and the shutter is driven by the filler cap when the filler cap is attached and the opening end of the atmosphere passage is opened. 5. The evaporative fuel treatment apparatus according to claim 4 , wherein the opening end is opened by being driven by a valve that opens and closes a refueling gun insertion hole of a restrictor provided at the refueling port during refueling. 6. A pressure detecting means for detecting a pressure is provided upstream of the on-off valve, and a failure of the fuel vapor treatment device is judged based on a change in pressure detected when the on-off valve is closed. claims 1, characterized in 5
6. The evaporated fuel processing device according to any one of 1.