JP2002013445A - Evaporation fuel treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporation fuel treating device capable of keeping adsorption efficiency of the evaporation fuel high during oil feeding and preventing the common adsorption performance from lowering due to the effect of the oil feed. SOLUTION: This evaporation fuel treating device is provided with a first guide passage 11 guiding the evaporation fuel generated in a fuel tank 5 in except for the oil feed to an adsorbent chamber 21, a second guide passage 12 guiding the evaporation fuel generated in the fuel tank 5 in the oil feed to the first adsorbent chamber 21, a purge channel 13 emitting the evaporation fuel adsorbed by the adsorbent from the first adsorbent chamber 21 to an intake channel of an internal combustion engine, a first atmosphere channel 44 communicating from a second adsorbent chamber 22 to the atmosphere, a second atmosphere channel 45 communicating from a third absorbent chamber 23 to the atmosphere, a first opening/closing valve 51 provided in the first atmosphere channel 44, a second opening/closing valve 52 provided in a second communication channel 27, and a control means 55 controlling the opening/closing actuation of the first opening/closing valve 51 and the second opening/closing valve 52. This device so controls as to open the first opening/closing valve 51 and to close the second opening/closing valve 52 at least, during oil feeding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an evaporative fuel processing apparatus for preventing evaporative fuel generated in a fuel tank of an internal combustion engine from diffusing into the atmosphere.

[0002]

2. Description of the Related Art FIG. 12 shows a general canister conventionally known as a U-shaped flow canister. The canister 01 has a canister body case 02 with a partition plate 03 inside.
Activated carbon, which is an adsorbent, is filled in both of the main chamber 04 and the sub chamber 05, and both chambers 04 and 05 are partially connected by a communication passage 06.

The main chamber 04 has a small-diameter normal-time charge connector 011 communicating with the fuel tank, a large-diameter refueling charge connector 012, and a purge connector 013 communicating with the intake pipe.
The sub chamber 05 is provided with a drain 014 communicating with the atmosphere.

[0004] The normal-time charge connector 011 is used to guide the evaporated fuel generated in the fuel tank during parking or engine operation into the canister 01 and adsorb it on the activated carbon. Is used when the evaporated fuel generated in large quantities at the time of refueling in communication with the filler tube or the like of the fuel tank is introduced into the canister 01 and is adsorbed on the activated carbon.

During traveling, the air sucked from the drain 014 by the suction negative pressure of the intake pipe passes through the activated carbon in the sub-chamber 05 to desorb the fuel, and further enters the main chamber 04 from the communication passage 06 to enter the main chamber 04.
The fuel is desorbed from the activated carbon and sent from the purge connector 013 to the intake pipe for combustion of the internal combustion engine.

During normal times (during parking or engine operation), the evaporated fuel generated in the fuel tank enters the main chamber 04 from the small-diameter normal-time charge connector 011, and the evaporated fuel is adsorbed by the activated carbon, and The remaining air, which enters the chamber 05 and is adsorbed by the activated carbon in the sub-chamber 05 to remove the HC component, is released from the drain 014.

At the time of refueling, the evaporative fuel generated by the refueling enters the main chamber 04 from the large-diameter refueling charge connector 012 as shown by an arrow in FIG. Since the air enters the chamber 05 and is adsorbed by the activated carbon of the sub-chamber 05 and the air is released from the drain 014, only the charge connector is different.

[0008] In general, if the canister L / D (length / diameter of the activated carbon layer) is large, the adsorbing performance is high. However, since the ventilation resistance is large, the problem that the lubrication is not performed smoothly is likely to occur. At this time, the efficiency of adsorption of the evaporated fuel is reduced.

In view of the above, an example in which a third chamber accommodating activated carbon is provided, the space between the auxiliary chamber and the sub chamber is communicated by a vent hole, and a drain is also provided in the third chamber (Japanese Patent Application Laid-Open No. 7-332171). There is. Normally, the evaporated fuel is adsorbed through the main chamber, the sub-chamber, and the third chamber, and the air is released from the drain of the third chamber. The fuel is adsorbed, and air is discharged from the drain of the sub chamber without entering the third chamber.

Since the canister L / D at the time of refueling is smaller than that of the normal canister L / D, and the canister airflow resistance at the time of refueling can be reduced, the efficiency of adsorbing evaporated fuel at the time of refueling does not decrease. Since the canister L / D can be set large, it is also possible to increase the efficiency of adsorbing the evaporated fuel during normal operation.

[0011]

However, the communication between the sub-chamber and the third chamber cannot be completely shut off. Therefore, if the fuel vapor breaks into the drain at the time of refueling, the third chamber will be closed.
Even a very small amount of fuel vapor may flow into the chamber. In such a case, the refueling evaporated fuel leaked into the third chamber causes
Thereafter, the adsorbing performance of the third chamber with the activated carbon for the evaporated fuel when the vehicle is stopped may decrease.

In the case where the heater and the temperature sensor are embedded in the canister, leakage of fuel vapor from the junction between the wiring for supplying power (or heat source) to the heater and the wiring of the temperature sensor to the canister body case ( There is a concern that the canister temperature may decrease due to leakage.

[0013] The present invention has been made in view of the above points, and an object thereof is to maintain a high efficiency of adsorbing fuel vapor at the time of refueling and to reduce the normal adsorption performance due to the influence of refueling. There is no evaporative fuel treatment device. Also provided is a structure for preventing the leakage of fuel vapor from the junction with the canister body due to the wiring of the heating means and the temperature detecting means.

[0014]

In order to achieve the above object, the invention according to the first aspect of the present invention comprises a first, a second, and a third adsorbent for respectively containing an adsorbent for adsorbing fuel vapor. A canister having an agent chamber, a first communication passage communicating the first adsorbent chamber and the second adsorbent chamber, and a second adsorbent chamber and the third adsorbent chamber. Second communicating
, A first introduction path for guiding the evaporated fuel generated in the fuel tank at times other than refueling to the first adsorbent chamber, and a first adsorbent chamber for evaporating fuel generated in the fuel tank during refueling. , A purge passage for discharging the vaporized fuel adsorbed by the adsorbent from the first adsorbent chamber to the intake passage of the internal combustion engine, and a communication from the second adsorbent chamber to the atmosphere. A first air passage, a second air passage communicating with the atmosphere from the third adsorbent chamber, a first on-off valve provided in the first air passage, and a second communication passage. A second opening / closing valve provided; and control means for controlling the opening / closing drive of the first opening / closing valve and the second opening / closing valve, wherein the control means comprises at least the first opening / closing valve at the time of refueling. Is opened to control the second on-off valve to be closed.

Since the second on-off valve is provided in the second communication passage connecting the second adsorbent chamber and the third adsorbent chamber, the second adsorbent is closed by closing the second on-off valve. The communication between the chamber and the third adsorbent chamber can be completely shut off.

Therefore, when the control means refuels, the first
When the on-off valve is opened and the second on-off valve is controlled to be closed, the evaporated fuel generated at the time of refueling is introduced into the first adsorbent chamber from the second introduction path, adsorbed by the adsorbent, and The air enters the second adsorbent chamber through the one communication passage, is adsorbed by the adsorbent in the second adsorbent chamber, and only the remaining air from which the HC component has been removed is discharged from the first air passage to the atmosphere. .

At this time, since only the first adsorbent chamber and the second adsorbent chamber pass, the air flow resistance can be set small, and the adsorption efficiency can be maintained high even with fuel vapor during refueling. Further, since the communication between the second adsorbent chamber and the third adsorbent chamber is completely shut off, the third adsorbent can be used even when the fuel vapor passes through the first air passage during refueling. There is no possibility that the fuel vapor leaks into the fuel chamber, and the adsorbing performance of the third adsorbent chamber by the activated carbon for the fuel vapor thereafter does not decrease.

According to a second aspect of the present invention, in the evaporative fuel treatment apparatus according to the first aspect, the first on-off valve and the second
Is an electromagnetic on-off valve, and the control means controls to open the first on-off valve after closing the second on-off valve during refueling.

At the time of refueling, after the second on-off valve is closed to completely cut off the communication between the second adsorbent chamber and the third adsorbent chamber,
By opening the first opening / closing valve and adsorbing the fuel vaporized fuel, the vaporized fuel leaks into the third adsorbent chamber even when the fuel vaporized fuel breaks into the first air passage. This can be reliably prevented.

According to a third aspect of the present invention, in the fuel vapor processing apparatus according to the first or second aspect, the second communication passage or the second atmospheric passage has a labyrinth structure.

When the refueling vaporized fuel breaks into the first air passage, the second on-off valve opens after refueling is completed,
When the second adsorbent chamber and the third adsorbent chamber communicate with each other,
It is possible to prevent the refueling evaporated fuel from flowing directly into the third adsorbent chamber by restricting the movement of the evaporated fuel by using the second communication passage or the second air passage as a labyrinth structure.

According to a fourth aspect of the present invention, in the evaporative fuel processing apparatus of the first aspect, a heating means for heating the adsorbent stored in the third adsorbent chamber is provided.

Activated carbon as an adsorbent emits heat of adsorption when the fuel vapor is adsorbed, and has the property of taking heat and cooling when the fuel vapor is desorbed. Therefore, during purging during running of the vehicle, the activated carbon cools due to the desorption of the evaporated fuel, and the desorption performance is reduced. In particular, the temperature of the third adsorbent chamber in which air is sucked from the second air passage is lowered. Therefore, by providing a heating means in the third adsorbent chamber and heating it, the desorption is promoted and the activated carbon is kept in a clean state, and thereafter, the adsorbing performance of the evaporated fuel at normal times can be enhanced.

According to a fifth aspect of the present invention, in the fuel vapor processing apparatus of the fourth aspect, a temperature detecting means for detecting a temperature of the adsorbent stored in the third adsorbent chamber is provided. I do.

Since the temperature of the third adsorbent chamber having a large temperature drop can be detected at appropriate times by the temperature detecting means, the temperature of the activated carbon can be adjusted to an appropriate temperature. Further, even after the start of the internal combustion engine, the adsorption performance of the evaporated fuel can be improved.

According to a sixth aspect of the present invention, in the evaporative fuel processing apparatus according to the fifth aspect, a wiring connected to the heating means and the temperature detecting means is provided from the side of the second atmospheric passage. And

On the side of the second air passage, the evaporated fuel is already adsorbed by the adsorbent in the third adsorbent chamber, so that the leak of the evaporated fuel from the joint around the wiring can be prevented, and A decrease in canister temperature due to leakage can be avoided. It is possible to efficiently prevent the fuel vapor from leaking from the junction around the wiring and to efficiently increase the temperature accompanying the heating of the adsorbent, thereby improving the performance of adsorbing the fuel vapor.

According to a seventh aspect of the present invention, in the evaporative fuel processing apparatus according to the fifth or sixth aspect, the wiring connected to the heating means and the temperature detecting means is embedded in the canister body case. Features.

By embedding the wiring in the canister body case, it is possible to reliably prevent the fuel vapor from leaking from the joint around the wiring. Also, the routing of the wiring is simplified.

According to an eighth aspect of the present invention, in the evaporative fuel processing apparatus according to the seventh aspect, a wiring connected to the heating means and the temperature detecting means is connected to the second adsorbent chamber and the third adsorption means. It is characterized in that it is embedded in a partition plate that partitions the medicine chamber.

By embedding the wiring in the partition plate, it is possible to reliably prevent the fuel vapor from leaking from the joint around the wiring. In addition, the routing of the wiring is simplified, and the assembling of the heating means and the temperature detecting means is also facilitated.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment according to the present invention will be described below with reference to FIGS. FIG. 1 is an overall configuration diagram showing an evaporative fuel processing apparatus 10 for an internal combustion engine 1 according to the present embodiment.

The canister 20, which stores activated carbon as an adsorbent, has partitioning plates 24, 25 inside the canister body case.
Thus, three chambers, a first activated carbon chamber 21, a second activated carbon chamber 22, and a third activated carbon chamber 23 are defined.

The partition plate 24 has a lower end lacking to form a first communication passage 26 which connects the first activated carbon chamber 21 and the second activated carbon chamber 22. The partition plate 25 has an upper end lacking and has a second communication passage 26. A second communication passage 27 that connects the activated carbon chamber 22 and the third activated carbon chamber 23 is formed.

In the first activated carbon chamber 21, the upper and lower filters 2
Activated carbon 21a is stored so as to be sandwiched between 8, 29, and the lower filter 29 is urged upward by a spring 31 via a holding plate 30 made of a porous material.

The lower filter 29 and the holding plate 30 are commonly used in the second activated carbon chamber 22, and the interior of the second activated carbon chamber 22 is provided between the upper filter 32 and the lower filter 29. Activated carbon 22a is sandwiched between them.

The inside of the third activated carbon chamber 23 contains upper and lower filters 3.
Activated carbon 23a is housed between 3 and 34, and the lower filter 34 is spring-loaded through a holding plate 35 made of porous material.
It is biased upward by 36.

The first activated carbon chamber 21 has a small-diameter normal-time charge connector 41, a large-diameter refueling charge connector 42, and a purge connector 43 in the upper part. A first air passage 44 communicating with the outside is formed, and a second air passage 45 communicating with the outside is formed below the third activated carbon chamber 23.

A first electromagnetic on-off valve 51 is provided in the first air passage 44.
The second electromagnetic on-off valve 52 is provided in the first communication passage 26.
The opening and closing drive of the two electromagnetic on-off valves 51 and 52 is controlled by an electronic control unit ECU55. Canister 20
Has the above structure.

On the other hand, the fuel tank 5 has a filler cap 7 fitted at the tip of a filler tube 6 for refueling, and a small-diameter normal vapor passage extending from the upper part of the tank.
11 is connected to the small-diameter normal-time charge connector 41 of the canister 20, and the large-diameter refueling vapor passage 12 extending from the filler tube 6 is connected to the large-diameter refueling charge connector 42 of the canister 20. Is done. The refueling vapor passage may extend from the fuel tank body.

The purge passage 13 connected to the purge connector 43 of the canister 20 is connected to the intake pipe 2 of the internal combustion engine 1 downstream of the throttle valve 3. Solenoid-operated on-off valves 15 and 16 are interposed between the refueling vapor passage 12 and the purge passage 13. The electromagnetic on-off valve 15 of the refueling vapor passage 12 may be a mechanical one-way valve.

In the evaporative fuel treatment apparatus 10 described above, the first electromagnetic on-off valve 51 is closed under the control of the ECU 55 and the second electromagnetic on-off valve is normally controlled during parking or engine operation.
Open 52.

As shown in FIG. 2, the evaporated fuel generated in the fuel tank 5 at normal time passes through the small-diameter normal-time vapor passage 11 from the normal-time charge connector 41 to the first activated carbon chamber 21 of the canister 20. The second electromagnetic on-off valve is introduced and adsorbed on the activated carbon 21a, then enters the second activated carbon chamber 22 through the first communication passage 26, is adsorbed on the activated carbon 22b, and is further opened.
After passing through the second activated carbon chamber 23, the air enters the third activated carbon chamber 23, is adsorbed on the activated carbon 23a, and the remaining air from which the HC component has been removed is passed through the second air passage.
Released from 45 to atmosphere.

As described above, the third activated carbon chamber 23 is added to the first and second activated carbon chambers 21 and 22 to increase the total activated carbon capacity and increase the adsorbing capacity of the evaporated fuel. Since the suction speed is slow, it is not necessary to consider the increase in the ventilation resistance due to the increase in the canister L / D.

During traveling (purge), the first electromagnetic on-off valve
The electromagnetic opening / closing valve 16 of the purge passage 13 is opened by closing the 51 and closing the second electromagnetic opening / closing valve 52 in the same state as in the normal state.

As shown in FIG. 3, during traveling, air is sucked from the second atmosphere passage 45 into the third activated carbon chamber 23 by the negative suction pressure of the intake pipe 2, the fuel is desorbed from the activated carbon 23a, and the valve is then opened. After passing through the second electromagnetic on-off valve 52, the fuel enters the second activated carbon chamber 22 and desorbs fuel from the activated carbon 22a, and further passes through the first communication passage 26 and enters the first activated carbon chamber 21 to activate the activated carbon 21a.
Fuel from the purge connector 43 and the purge passage 13
To the intake pipe 2.

That is, all the activated carbon in the canister 20, that is, the activated carbons 21 a, 22 of the first, second, and third activated carbon chambers 21, 22, and 23 are activated by the air sucked from the second atmosphere passage 45.
a, 23a, the adsorbed fuel is desorbed and the intake pipe 2
And supplied to the internal combustion engine 1 for combustion.

At the time of refueling, when the filler cap 7 is removed and the refueling gun is inserted into the refueling port of the filler tube 6, the sensor operates to detect that refueling is performed.
The detection signal is input to the ECU 55.

When this detection signal is input, the ECU 55
First, the second electromagnetic on-off valve 52 is controlled to be closed so as to shut off the second communication passage 27 between the second activated carbon chamber 22 and the third activated carbon chamber 23. Then, the first solenoid on-off valve of the first atmospheric passage 64
Control to open 51. At substantially the same time, the electromagnetic on-off valve 15 of the fuel supply vapor passage 12 is opened.

As shown in FIG. 4, during refueling, a large amount of fuel vapor generated by refueling is supplied to a large-diameter refueling vapor passage.
12, flows at a high flow rate, is introduced from the refueling charge connector 42 into the first activated carbon chamber 21, is adsorbed by the activated carbon 21 a, and then passes through the first communication passage 26 to the second activated carbon chamber 22.
The remaining air, from which the HC component has been removed, is adsorbed by the activated carbon 22b, passes through the opened first electromagnetic on-off valve 51, and is discharged from the first air passage 44 to the atmosphere.

The fuel vaporized fuel is supplied to the first activated carbon chamber 21 and the second activated carbon chamber 21.
, And is adsorbed by the activated carbons 21a and 22b and does not pass through the third activated carbon chamber 23, so that the canister L /
D is small and ventilation resistance is small. Therefore, the fuel vapor at the time of refueling can be efficiently adsorbed, and the adsorption efficiency can be maintained high.

A second activated carbon chamber 22 and a third activated carbon chamber 23
Is completely shut off by the closing of the second electromagnetic on-off valve 52, the first electromagnetic on-off valve 51 opens, so that the fuel vapor passes through the first air passage 44 during refueling. Even in the case of, the evaporated fuel does not leak into the third activated carbon chamber 23 at all, and the adsorbing performance of the third adsorbent chamber 23 by the activated carbon 23a for the evaporated fuel in the normal state thereafter does not decrease.

The opening and closing timing of the first electromagnetic on-off valve 51 and the second electromagnetic on-off valve 52 can be freely controlled by the ECU 55, so that the opening and closing control can be performed at an appropriate timing not only at the time of refueling.

For example, while the canister is being purged during traveling, the first activated carbon chamber 23 is purged when a predetermined time has elapsed from the start of traveling (purge start) and the third activated carbon chamber 23 has been sufficiently purged. By controlling the electromagnetic on-off valve 51 to be opened and the second electromagnetic on-off valve 52 to be closed, the purge air does not pass through the third activated carbon chamber 23 but directly from the first air passage 44 to the second activated carbon chamber. 22 and the first through the first communication passage 26
Of the fuel from the activated carbons 22a, 21a can be further promoted.

By controlling the switching between the first electromagnetic on-off valve 51 and the second electromagnetic on-off valve 52, the purge air is supplied to the third and third electromagnetic on-off valves 51 and 52.
A flow path for flowing in the order of the second and first activated carbon chambers 23, 22 and 21, and a second and first activated carbon chambers 22 and 21 without passing through the third activated carbon chamber 23.
Can be switched in a predetermined time.

For example, the activated carbon 23a of the third activated carbon chamber 23 whose temperature has been lowered by the purge is replaced with the second activated carbon chamber 22,
The temperature can be increased even during purging without switching through the third activated carbon chamber 23 by switching to the flow path that only flows through 21, and after switching to the flow path that passes through the third activated carbon chamber 23 again after the temperature rise, the purging is promoted. be able to.

Next, another embodiment will be described with reference to FIG. The basic structure of the canister 60 according to the present embodiment is the same as that of the canister 20 according to the above embodiment, and the same members are denoted by the same reference numerals.

The canister 60 has the second activated carbon chamber 22 and the third activated carbon chamber 22.
Is formed as a labyrinth-like passage 61 having a labyrinth structure from the space above the canister 60 to the space below the canister 60. The second communication passage communicating with the activated carbon chamber 23 of the labyrinth-like passage 61 A second electromagnetic on-off valve 52 is arranged at the end of the activated carbon chamber 22 side.

The labyrinth-like passage 61 has a ventilation resistance, and when the refueling vaporized fuel breaks into the first atmospheric passage 44, the second electromagnetic on-off valve 52 is opened after refueling is completed.
When the second activated carbon chamber 22 and the third activated carbon chamber 23 communicate with each other, it is possible to prevent the fuel vaporized fuel from flowing directly into the third activated carbon chamber 23.

Since the labyrinth-like passage 61 is formed from the space above the canister 60 to the space below the canister 60,
The second atmosphere passage 62 provided in the third activated carbon chamber 23 can have an opening direction in the same direction as the first atmosphere passage 44, so that the layout property when mounted on a vehicle can be improved.

FIG. 6 shows a modification of the embodiment shown in FIG. 5. In this canister 70, a labyrinth-like passage 71 is provided between the third activated carbon chamber 23 and the second atmospheric passage 72. The other structure is the same as that of the canister 20 shown in FIGS.

If the refueling vaporized fuel breaks through the first air passage 44 due to the large airflow resistance in the second air passage 72, the second electromagnetic on-off valve 52 is closed after refueling. When the second activated carbon chamber 22 and the third activated carbon chamber 23 communicate with each other, it is possible to suppress the refueling evaporated fuel from flowing directly into the third activated carbon chamber 23. In addition, the second air passage 72 can have an opening direction in the same direction as the first air passage 44, so that the layout property when mounted on a vehicle can be improved.

Next, FIG. 7 shows a canister 80 according to an embodiment provided with a heater as a heating means in order to enhance the desorption performance of activated carbon. A heater 81 is provided inside the activated carbon layer 23a in the third activated carbon chamber 23 of the canister 20 shown in FIGS.
The temperature sensor 82 is inserted in the activated carbon 23a layer.

During the purge, the activated carbon cools due to the desorption of the evaporated fuel, and the desorption performance is reduced. In particular, the desorption of the third activated carbon chamber 23 where air is directly sucked in from the second air passage 45 starts. Since the amount of desorption immediately after is large, the temperature decreases quickly and the temperature decreases greatly.
By heating the activated carbon 23a from the inside by providing a heater 81 inside the interior a, the desorption is promoted and the activated carbon 23a is kept in a clean state, and thereafter, the normal performance of adsorbing the evaporated fuel can be improved.

The fuel vapor at the time of refueling is supplied to the activated carbons 21 a and 22 in the first activated carbon chamber 21 and the second activated carbon chamber 22 as described above.
Therefore, the adsorption performance is not affected by the influence of the temperature rise of the third activated carbon chamber 23 because it is adsorbed only by a.

Further, since the adsorption speed of the evaporated fuel in the normal state is very gentle, the activated carbon in the third activated carbon chamber 23 is not changed until the evaporated fuel reaches the third activated carbon chamber 23 after the vehicle stops. The temperature of 23a is cooled to about the outside temperature. Therefore, there is no effect of temperature rise after heating.
It is possible to prevent a decrease in the adsorbing performance of the evaporated fuel a.

By inserting the temperature sensor 82 in the layer of the activated carbon 23a in the third activated carbon chamber 23, the ECU can monitor the temperature of the activated carbon 23a during running of the vehicle and control it to an appropriate temperature.

The canister 90 shown in FIG. 8 is a modified example of the canister 80 shown in FIG. 7, in which a heater 91 is provided on the outer periphery of the case of the third activated carbon chamber 23.
23a can be warmed. Note that a gap is provided between the second activated carbon chamber 22 and the heater 91 so that the heat of the heater 91 does not affect the second activated carbon chamber 22.

At the time of desorption, the activated carbon 23a in the third activated carbon chamber 23 is heated from the outside by the heater 91 to promote desorption and keep the activated carbon 23a in a clean state. Can be enhanced.

A temperature sensor 92 is inserted in the activated carbon 23a, and the temperature of the activated carbon 23a can be monitored by the ECU and adjusted to an appropriate temperature. In addition, by operating the heater 91 for a predetermined time after the start of the internal combustion engine to warm the activated carbon, the desorption performance of the evaporated fuel can be promptly improved.

As a heater, a pair of electrodes are provided so that the activated carbon is interposed in the canister, and electricity is supplied to the heater, whereby the activated carbon itself generates heat and the temperature can be raised efficiently.

Next, the wiring 101 between the heater 101 and the temperature sensor 102
FIG. 9 illustrates the canister 100 in which the a and 102a are devised. A heater 101 and a temperature sensor 102 are provided inside the activated carbon layer 23a in the third activated carbon chamber 23, and the heater 101
And wires 101a and 102a connected to the temperature sensor 102 extend to the outside from the second air passage 45 side.

A space is formed on the second atmosphere passage 45 side of the third activated carbon chamber 23 by the pressing plate 35 being urged by a spring 36, and a joint 101b between the wirings 101a and 102a and the canister body case is formed. , 102b are not in contact with the activated carbon 23a, so that the fuel vapor adsorbed on the activated carbon 23a does not leak easily.

Even if the joints 101b and 102b are peeled off for some reason, the evaporated fuel does not leak directly to the outside.

FIG. 10 shows still another modification. In the canister 110, wirings 111a and 112a connected to a heater 111 and a temperature sensor 112 provided inside an activated carbon layer 23a in a third activated carbon chamber 23 are embedded in a partition plate 115 of a canister body case. It extends outside from the atmosphere passage 45 side.

Since the wires 111a and 112a are embedded in the partition plate 115, it is possible to reliably prevent the fuel vapor from leaking around the wires 111a and 112a. Further, the partition plate 115 is a partition plate between the second activated carbon chamber 22 and the third activated carbon chamber 23, and the wirings 111a and 112a are also short, so that the layout is simplified.

FIG. 11 shows still another modification. FIG. 11 is a view showing the canister 120 in the process of being assembled.
Between the activated carbon chamber 22 and the third activated carbon chamber 23
Indicates where is inserted.

The second in the canister body case 120a
A pair of guide ribs 126 are respectively provided on the inner surfaces of the opposed side walls between the activated carbon chamber 22 and the third activated carbon chamber 23 so as to project from the lower end opening of the canister body case 120a.
25 is guided by the guide rib 126 and inserted.

The partition plate 125 has wirings 121a, 121a inside.
2a is formed in an embedded state, and the wirings 121a,
122a is connected to a heater 121 and a temperature sensor 122 provided inside the activated carbon 23a layer in the third activated carbon chamber 23, respectively.

One of the wirings 121 a and 122 a has a partition plate 126.
Extends to the third activated carbon chamber 23 side, is connected to the heater 121 and the temperature sensor 122, and the other extends from the partition plate 126 to the lower end opening side of the canister body case 120a. Heater 1
A wire 121a connected to the temperature sensor 122 is connected to a power supply controlled by the ECU.
Connected to input terminal of CU.

As described above, the wirings 121a and 122a are provided on the partition plate.
Since it is embedded in the 125, leakage of fuel vapor from the junction around the wiring can be reliably prevented. Wiring is also simplified, and the heater 121 and temperature sensor 122
Can be easily attached.

In each of the above embodiments, the activated carbons 21a, 22a, and 23 of the first, second, and third activated carbon chambers 21, 22, and 23 are used.
Granulated carbon is used as a, but crushed carbon having high ventilation resistance may be used as the activated carbon in the third activated carbon chamber 23.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an evaporated fuel processing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a flow of evaporated fuel in a normal state in a canister of the evaporated fuel processing apparatus.

FIG. 3 is a diagram showing a flow of evaporated fuel at the time of purging in the canister.

FIG. 4 is a diagram showing a flow of evaporated fuel at the time of refueling in the canister.

FIG. 5 is a view showing a structure of a canister provided with a labyrinth passage according to another embodiment.

FIG. 6 is a view showing a modified example of the canister shown in FIG.

FIG. 7 is a diagram showing a structure of a canister provided with a heater according to another embodiment.

FIG. 8 is a view showing a modified example of the canister shown in FIG.

FIG. 9 is a view showing a structure of a canister according to still another embodiment.

FIG. 10 is a diagram showing a structure of a canister according to still another embodiment.

FIG. 11 is a view showing a modified example of the canister shown in FIG.

FIG. 12 is a view showing a structure of a conventional canister.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... Intake pipe, 3 ... Throttle valve, 5
... Fuel tank, 6 ... Filler tube, 7 ... Filler cap, 10 ... Evaporation fuel treatment device, 11 ... Normal vapor passage, 12 ... Refueling vapor passage, 13 ... Purge passage, 15, 16
... electromagnetic on-off valve, 20 ... canister, 21 ... first activated carbon chamber, 22 ... second activated carbon chamber, 23 ... third activated carbon chamber, 24, 25
... partition plate, 26 ... first communication path, 27 ... second communication path, 2
8, 29: filter, 30: holding plate, 31: spring, 32, 3
3, 34 ... filter, 35 ... holding plate, 36 ... spring, 41 ...
Charge connector for normal use, 42 Charge connector for refueling, 43 Purge connector, 44 First air passage, 45
2nd atmosphere passage, 51 ... 1st electromagnetic on-off valve, 52 ... 2nd electromagnetic on-off valve, 55 ... ECU, 60 ... canister, 61 ... labyrinth passage, 62 ... 2nd atmosphere passage, 70 ... canister, 71…
Labyrinth passage, 72 second air passage, 80 canister, 81 heater, 82 temperature sensor, 90 canister, 91
... heater, 92 ... temperature sensor, 100 ... canister, 101 ... heater, 102 ... temperature sensor, 110 ... canister, 111 ... heater, 112 ... temperature sensor, 115 ... partition plate, 120 ... canister, 121 ... heater, 122 ... temperature Sensor, 125… Partition plate, 1
26… Guide rib.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B60K 15/077 F02M 37/00 301H F02M 37/00 301 B60K 15/02 L (72) Inventor Shoichi Kitamoto Saitama 1-4-1, Chuo, Wako-shi, F-term F-term in Honda R & D Co., Ltd. (Reference) 3D038 CA22 CB01 CC05 3G044 BA20 BA30 CA16 CA17 DA06 FA12 GA03 GA04 GA12 GA13 GA15 GA16 GA20 GA24 GA28 GA29 GA30

Claims (8)

[Claims] 1. A canister having first, second, and third adsorbent chambers for storing adsorbents for adsorbing evaporated fuel, respectively; and the first adsorbent chamber and the second adsorbent chamber. A first communication path that communicates with the first adsorbent; a second communication path that communicates the second adsorbent chamber with the third adsorbent chamber; A first introduction path leading to the adsorbent chamber, a second introduction path leading evaporative fuel generated in the fuel tank at the time of refueling to the first adsorbent chamber, and a second introduction path for evaporating fuel adsorbed by the adsorbent. A purge passage discharging from the first adsorbent chamber to the intake passage of the internal combustion engine; a first air passage communicating from the second adsorbent chamber to the atmosphere; and a first air passage communicating from the third adsorbent chamber to the atmosphere. 2 air passage, a first on-off valve provided in the first air passage, and a second communication passage. A second opening / closing valve provided; and control means for controlling opening / closing drive of the first opening / closing valve and the second opening / closing valve, wherein the control means is configured to supply the first opening / closing valve at least at the time of refueling. And controlling the second on-off valve to be closed. 2. The on-off valve according to claim 1, wherein the first on-off valve and the second on-off valve are electromagnetic on-off valves. 2. The evaporative fuel treatment apparatus according to claim 1, wherein control is performed to open the fuel cell. 3. The labyrinth structure of the second communication passage or the second air passage.
Alternatively, the evaporated fuel processing apparatus according to claim 2. 4. A heating device for heating an adsorbent housed in the third adsorbent chamber is provided.
The evaporative fuel treatment device according to any one of the preceding claims. 5. The evaporative fuel treatment apparatus according to claim 4, further comprising a temperature detecting means for detecting a temperature of the adsorbent stored in the third adsorbent chamber. 6. The evaporative fuel treatment apparatus according to claim 5, wherein a wiring connected to the heating means and the temperature detecting means is installed from the second air passage side. 7. The evaporative fuel processing apparatus according to claim 5, wherein wiring connected to the heating means and the temperature detecting means is embedded in the canister body case. 8. A wiring connected to said heating means and said temperature detecting means is buried in a partition plate separating said second adsorbent chamber and said third adsorbent chamber. The evaporative fuel treatment device according to any one of the preceding claims.