JPH1018921A - Vaporized fuel control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uttery eliminate the possibility of the inflow of fuel or vaporized fuel in a fuel tank into a canister side, to prevent the deterioration of canister due to the fuel or vaporized fuel and to ensure canister performance by closing a refuelling vapor control valve at the time of stopping/operating an internal combustion engine. SOLUTION: A refueling vapor control valve 26A is provided on a fuel tank 16A, and is constituted of a first chamber 26A-1 partitioned by a diaphragm 26A-5 and formed for communicating with the oiling side vicinity of the oil pipe of the fuel tank 16A, and a second chamber 26A-2 partitioned by the diaphragm 26A-5 and formed for communicating with a canister and the fuel tank 16A, and a communicating means for communicating between the first and second chambers 26A-1 and 26A-2 is provided. Also, this device is provided with a communication passage for communicating the fuel tank upper part and the oiling side vicinity of the oil pipe of the fuel tank, and on the communication passage, an opening/closing valve to be opened when an internal combustion engine is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an evaporative fuel control system for an internal combustion engine, and particularly to a fuel vapor control valve that closes a fuel vapor control valve when the internal combustion engine is stopped and in operation, so that fuel and evaporative fuel in a fuel tank can be supplied to a canister. TECHNICAL FIELD The present invention relates to an evaporative fuel control device for an internal combustion engine that can prevent deterioration of a canister due to fuel or evaporative fuel and can ensure canister performance without any risk of flowing into the evaporator.

[0002]

2. Description of the Related Art In a vehicle, evaporated fuel leaking into the atmosphere from a fuel tank or the like contains a large amount of hydrocarbons (HC) and is one of the causes of air pollution, and also leads to fuel loss. For this reason, various techniques for preventing this are known. As a typical example, there is an evaporative fuel control device (evaporation system) in which evaporative fuel in a fuel tank is separated (purged) from a canister containing an adsorbent such as activated carbon during operation of the internal combustion engine and supplied to the internal combustion engine.

Further, as an evaporative fuel control device for an internal combustion engine, there is one disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 7-279788. The fuel tank disclosed in this publication is provided with a shutter that is opened at the upper end of the filler tube by inserting a fuel filler gun, a vent tube communicating the upper space in the tank body with the canister, and a vent tube inside the tank body. A supercharging prevention valve is provided at the facing end, and a vent cut valve that closes the vent tube line in conjunction with the opening and closing operation of the shutter is provided in the middle of the vent tube line. A space that connects the space between the vent cut valve and the upper space inside the filler tube is provided on the side wall of the filler tube, without increasing the size and weight of the supercharging prevention valve.
This prevents sticking of the valve and prevents the liquid level in the filler tube from rising when the temperature inside the tank body rises.

[0004]

In a conventional evaporative fuel control system for an internal combustion engine, as shown in FIG.
Reference numeral 2 denotes an internal combustion engine mounted on a vehicle (not shown), 4 denotes an intake manifold, 6 denotes an intake passage, 8 denotes a surge tank, 10 denotes a throttle valve, 12 denotes a fuel injection valve, 14 denotes an air cleaner, 16
Is a fuel tank. The fuel tank 16 has a fuel supply pipe (filler hose) 20 provided with a fuel supply cap 18.
Are connected. The oil supply pipe 20 forms an oil supply passage (filler passage) 22.

In the fuel tank 16, a fuel pump (not shown), a tank pressure sensor 24, a fuel vapor control valve 26 and a float valve 28 having a float valve body (not shown) which moves up and down according to the amount of fuel, and a fuel amount A level gauge 30 for detection is provided. The fuel vapor control valve 26 is connected to the fuel tank 16.
It is arranged at a substantially central part of. In addition, the float valve 28
Is smaller than the fuel vapor control valve 26, and is disposed apart from the central portion of the fuel tank 16. One end of a fuel supply passage (not shown) is connected to the fuel pump. The other end of the fuel supply passage is provided in communication with the fuel injection valve 12.
A fuel pressure regulator 32 is connected to the fuel injection valve 12. One end of a fuel return passage (not shown) is connected to the fuel pressure regulator 32. The other end of the fuel return passage is provided to be open in the fuel tank 16.

A positive pressure type evaporative fuel control device (evaporation system) 34 is provided between the fuel tank 16 and the intake system of the internal combustion engine 2.
Is provided.

In the evaporative fuel control device 34, one end of the evaporative passage communicates with the fuel tank 16, for example, the other end and one end of the first to third evaporative passages 36 to 40 constitute the intake passage 6. A canister 44 is provided between the surge tank 8 and the other end of the purge passage 42 communicating with the surge tank 8.

[0008] One end of the first evaporation passage 36 is connected to the fuel vapor control valve 2 in the fuel tank 16.
6, and one end of the second evaporation path 38 is communicated with the third evaporation path 40 in the middle.

One end of the third evaporation passage 40 is opened and closed by a float valve 28 which is guided in a float guide 46 in the fuel tank 16 and moves up and down. It is arranged at a position separated from the upper part of the predetermined distance 16 by a predetermined distance.

In the fuel tank 16, the first
There is a gap between one end of the evaporative passage 36 and one end of the third evaporative passage 40.

The other end of the first evaporation passage 36 communicates with an upper position of the canister 44. Second evaporation passage 38
Is in communication with the third evaporation passage 40 in the middle. The other end side of the third evaporation passage 40 communicates with the upper position of the canister 44.

[0012] The fuel vapor control valve 2
6 includes a float valve body (not shown), a first chamber serving as a pressure action chamber and a second chamber serving as a passage communication chamber defined by a diaphragm serving as a partition body in a housing (not shown). The chamber is provided with a spring that presses the diaphragm, and further provided with a valve seat that opens and closes the first evaporation passage 36 when the central portion of the diaphragm comes into contact with and separates from the second chamber. 1st room and refueling passage 22
Are communicated by the tank-side communication passage 48.

A solenoid valve (VSV) 50 comprising a two-way solenoid valve is provided in the second evaporation passage 38.

The third evaporation passage 40 has an internal combustion engine 2
When the internal pressure of the fuel tank 16 becomes larger than a predetermined set pressure at the time of stop, a pressure control valve 52 as an internal pressure control valve for opening the third evaporation passage 40 is provided. This pressure control valve 52
Is composed of a check valve, and has a partition body in a housing (not shown) and a check body provided in the partition body. The other end of the second evaporation passage 38 communicates with the canister 44 with respect to the pressure control valve 52, that is, the third evaporation passage 40 that bypasses the pressure control valve 52. Further, the above set pressure is set to
6 is a pressure value for closing the pressure control valve 52 even during refueling.

In the middle of the purge passage 42, a purge valve (solenoid valve) 54 for controlling the amount of fuel evaporated to the intake passage 6 according to the operating state of the internal combustion engine 2 is provided.

The other ends of the first to third evaporation passages 36 to 40 and the other end of the purge passage 42 are opened side by side in the upper part of the canister 44. Also, this canister 4
4 is provided with one end of an atmosphere communication passage 56 in communication therewith. An air cut valve (solenoid valve) 58 for opening and closing the atmosphere communication passage 56 is provided at the other end of the atmosphere communication passage 56.
And an air cleaner 60.

The canister 44 adsorbs and holds the fuel vapor generated in the fuel tank 16 and guided to the first to third evaporation passages 36 to 40, and from the atmosphere communication passage 56 during operation of the internal combustion engine 2. The evaporated fuel adsorbed and held by the introduced atmosphere is released and supplied from the purge passage 42 to the intake passage 6.

The fuel injection valve 12, the solenoid valve 50, the purge valve 54, and the air cut valve 58 are connected to control means 62.

Before refueling the fuel tank 16 of the internal combustion engine 2, the fuel vapor control valve 26 and the solenoid valve 50 are closed as shown in FIG. Tank pressure is maintained.

At this time, when the tank internal pressure of the fuel tank 16 becomes larger than a predetermined set pressure, the pressure control valve 5
2 operates to open the third evaporative passage 40, and the fuel vapor generated in the fuel tank 16 is removed from the third evaporative passage 40.
By the canister 44.

Further, during refueling of the fuel tank 16 of the internal combustion engine 2, as shown in FIG. 11, negative pressure acts on the first chamber of the fuel vapor control valve 26 to open the fuel vapor control valve 26. As a result, the fuel vapor generated in the fuel tank 16 is adsorbed on the canister 44 by the first evaporation passage 36.

The fuel vapor adsorbed by the canister 44 is supplied to the purge passage 42 according to the operating state of the internal combustion engine.
Through the intake passage 6.

Further, after refueling the fuel tank 16 of the internal combustion engine, as shown in FIG. 12, the fuel vapor control valve 26 and the solenoid valve 50 are closed, and the pressure control valve 52 Holds tank internal pressure.

During the operation of the internal combustion engine, as shown in FIG.
6 and the pressure control valve 52 are closed, but the solenoid valve 50 is opened, and the fuel vapor generated in the fuel tank 16 is supplied to the second evaporation passage 38 and the third evaporation passage 40.
Is adsorbed to the canister 44.

Further, when the fuel tank 16 of the internal combustion engine is full just after refueling, as shown in FIG.
The relationship between the pressure P1 in the first chamber of the fuel vapor control valve 26 and the pressure P2 in the fuel tank 16 is P2> P1, and the difference between the oil level in the fuel supply pipe 20 and the oil level in the fuel tank 16 is calculated as follows. Assuming that h1 (〓Ag), by adding a difference h1 (〓Ag) to the pressure P1 in the first chamber, the pressure P2 becomes substantially equal to the pressure P2 in the fuel tank 16.

During running after the fuel tank 16 of the internal combustion engine is filled with fuel, the fuel vapor control valve 26 is opened as shown in FIG. 15, and the canister (not shown) and the fuel tank 16 (not shown) are opened.
Is communicated through a first evaporation passage 36, and the pressure P′1 in the first chamber of the fuel vapor control valve 26
And the pressure P'2 in the fuel tank 16 is P'2>P'1, and the difference between the oil level in the fuel supply pipe 20 and the oil level in the fuel tank 16 is h'2 (〓Ag). Then, the pressure P ′ in the first chamber is
By adding the difference h′2 (〓Ag) to 1, the pressure becomes substantially equal to the pressure P′2 in the fuel tank 16.

As a result, a pressure difference is generated between the pressure in the first chamber of the fuel vapor control valve and the pressure in the fuel tank, and when this pressure difference overcomes the biasing force of the fuel vapor control valve, the internal combustion engine At the time of stop and operation, the fuel and the evaporated fuel in the fuel tank flow into the canister side, and the fuel and the evaporated fuel deteriorate the canister, so that the canister performance cannot be secured and the evaporative emission increases. is there.

[0028]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, the present invention provides a method in which an evaporative passage communicating with a fuel tank and a purge passage communicating with an intake passage of an intake system of an internal combustion engine. While the internal combustion engine is stopped, the evaporated fuel generated in the fuel tank and guided to the evaporative passage is adsorbed and held, and the evaporated fuel adsorbed and held by the air introduced from the atmosphere communication passage during the operation of the internal combustion engine. A canister for releasing the fuel from the purge passage to the intake passage, and a purge valve for controlling the amount of fuel evaporated to the intake passage in accordance with an operation state of the internal combustion engine in the middle of the purge passage; A float valve is provided in the tank that moves up and down according to the amount of fuel to open and close the evaporative passage,
In the evaporative fuel control device for an internal combustion engine provided with a tank internal pressure control valve that opens an evaporative passage when an operation pressure from the fuel tank becomes larger than a set pressure, a fuel vapor control valve is provided in the fuel tank. A first chamber defined by a diaphragm and connected to the fuel supply pipe near the fuel supply pipe, and a second chamber defined by a diaphragm and connected to the canister and the fuel tank; And a communication means for connecting the first chamber and the second chamber.

Further, between the evaporative passage communicating with the fuel tank and the purge passage communicating with the intake passage of the internal combustion engine, the gas generated in the fuel tank while the internal combustion engine is stopped is generated in the evaporative passage. A canister that adsorbs and holds the introduced evaporative fuel and releases the evaporative fuel that is adsorbed and held by the air introduced from the atmosphere communication passage during the operation of the internal combustion engine and supplies the evaporative fuel from the purge passage to the intake passage; In the middle of the purge passage, a purge valve for controlling the amount of fuel vapor to the intake passage according to the operation state of the internal combustion engine is provided, and a float valve for moving the fuel tank up and down to open and close the evaporation passage is provided, An evaporative fuel control device for an internal combustion engine provided with a tank internal pressure control valve that opens an evaporative passage when the operating pressure from the fuel tank becomes larger than a set pressure. There are, characterized in that during the communication passage provided with a communication passage for communicating the oil supply side near the fill pipe of the fuel tank top and fuel tank provided with a closing valve which opens when the internal combustion engine operation.

[0030]

According to the configuration of the present invention, when the internal combustion engine is stopped and the engine is running, the communication means connects the first chamber and the second chamber of the fuel vapor control valve with the fuel vapor control valve. The valve is closed, and there is no danger of fuel or evaporative fuel in the fuel tank flowing into the canister, preventing deterioration of the canister due to fuel or evaporative fuel and ensuring canister performance.

When the internal combustion engine is stopped and the engine is running, the on-off valve is opened during operation of the internal combustion engine to connect the upper portion of the fuel tank with the vicinity of the fuel supply pipe of the fuel tank so that the fuel and the evaporated fuel in the fuel tank are removed. There is no danger of flowing into the canister, preventing deterioration of the canister due to fuel or evaporative fuel, and ensuring canister performance.

[0032]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention;

FIGS. 1 to 3 show a first embodiment of the present invention. In the first embodiment, a portion performing the same function as that used in the above-described prior art will be described by adding a symbol "A" to the symbol of the portion. The description will be made with "."

As shown in FIG. 1, an oil supply pipe (filler hose) 20A provided with an oil supply cap 18A is connected to a fuel tank 16A of a vehicle (not shown). The oil supply pipe 20A forms an oil supply passage (filler passage) 22A.

In the fuel tank 16A, a fuel pump (not shown), a tank pressure sensor (not shown), and a fuel vapor control valve 26A and a float valve 28A having a float valve body 26A-3, which will be described later, move up and down according to the amount of fuel. And a level gauge 30 for detecting a fuel amount.
A is provided.

A positive pressure type evaporative fuel control device (evaporation system) 34A is provided between the fuel tank 16A and an intake system of an internal combustion engine (not shown).

In this evaporative fuel control device 34A,
An evaporating passage having one end communicating with the fuel tank 16A,
For example, a purge passage (not shown) in which the other end and one end of each of the first to third evaporation passages 36A to 40A (the second evaporation passage is not shown) communicates with a surge tank (not shown) constituting an intake passage (not shown). (Not shown), a canister (not shown) is provided.

An end of the first evaporation passage 36A on one end side is:
The fuel vapor control valve 26A on the fuel tank 16A side is connected to the second chamber 26A-2 of the fuel vapor control valve 26A.
One end of the evaporative passage is communicated with the third evaporative passage 40A.

The end of one end of the third evaporation passage 40A is
The float guide body 46A is disposed at a position separated from the upper portion of the fuel tank 16 by a predetermined distance so as to be opened and closed by a float valve 28A that moves up and down while being guided in the float guide body 46A in the fuel tank 16A. .

In the fuel tank 16A, one end of the first evaporation passage 36A and the third evaporation passage 4A are connected.
There is a gap between the one end of OA and the other end.

The other end of the first evaporation passage 36A communicates with an upper position of a canister (not shown),
The other end of the evaporative passage communicates with the middle of the third evaporative passage 40A, and the other end of the third evaporative passage 40A communicates with an upper position of a canister (not shown).

The above-mentioned fuel vapor control valve 2
6A includes a float valve body 26A-3 and a housing 26A.
A first chamber 26A-1 serving as a pressure action chamber and a second chamber 26A-2 serving as a passage communication chamber defined by a diaphragm 26A-5 serving as a partition body in A-4 are provided. -1 is provided with a spring 26A-6 for pressing the diaphragm 26A-5, and further, the second chamber 26A
A valve seat (not shown) is provided for opening and closing the first evaporation passage 36A by bringing the central portion of the diaphragm 26A-5 into and out at -2. The first chamber 26A-1 and the oil supply passage 22A are connected by a tank-side communication passage 48A.

Then, a fuel vapor control valve 26A is provided in the fuel tank 16A, and the fuel vapor control valve 26A is connected to the diaphragm 26.
A-5, the fuel supply pipe 2 of the fuel tank 16A
A first chamber 26A formed to communicate with the vicinity of the oil supply side of 0A.
1 and a second chamber 26A-2 partitioned by a diaphragm 26A-5 and formed to communicate with a canister (not shown) and a fuel tank 16A, and the first chamber 26A-
A communication means 72A for connecting the first and second chambers 26A-2 is provided.

More specifically, the communication means 72A is connected to the first
Communicating passage 7 connecting chamber 26A-1 and second chamber 26A-2
4A, and an orifice 76A is provided in the middle of the communication passage 74A.

A valve (not shown) for detecting a lead-free or leaded refueling gun (not shown) is provided in a refueling pipe (filler hose) 20A near the refueling cap 18A of the fuel tank 16A. .

Next, the operation will be described.

Immediately after refueling the fuel tank 16A,
As shown in FIG. 1, the fuel vapor control valve 2
6A and a solenoid valve (not shown) are closed, a pressure control valve (not shown) holds the tank internal pressure of the fuel tank 16A, and excess tank internal pressure is adsorbed to the canister via the pressure control valve.

The relationship between the pressure P1 in the first chamber 26A-1 of the fuel vapor control valve 26A and the pressure P2 in the fuel tank 16A is determined by the oil level in the fuel supply pipe 20A and the oil level in the fuel tank 16A. The difference between the pressure P1 and the pressure P1 in the first chamber 26A-1 is h2 (〓Ag).
, The pressure becomes equal to the pressure P2 in the fuel tank 16A. P3 is the pressure in the second chamber 26A-2 of the fuel vapor control valve 26A.

After a short time has elapsed since the fuel was supplied to the fuel tank 16A, as shown in FIG. 2, the difference between the oil level in the oil supply pipe 20A and the oil level in the fuel tank 16A disappeared, and the fuel vapor control valve 26A The relationship between the pressure P1 in the first chamber 26A-1 and the pressure P2 in the fuel tank 16A is P1 = P2.

During running after the fuel tank 16A is refueled and the fuel tank 16A is full, the fuel in the fuel tank 16A is supplied to a predetermined location as shown in FIG. Although the state close to the target tank is maintained, the float valve body 26A-3 is lowered and is in an open state.

The inside of the fuel tank 16A communicates with the second chamber 26A-2 of the fuel vapor control valve 26A, and the inside of the fuel tank 16A communicates with the first chamber 26A-1 of the fuel vapor control valve 26A. The pressure P'1 in the first chamber 26A-1 of the fuel vapor control valve 26A and the pressure P'2 in the fuel tank 16A are made equal through an orifice 76A in the middle of the communication passage 74A.

At this time, when the pressure P'1 in the first chamber 26A-1 of the fuel vapor control valve 26A becomes equal to the pressure P'2 in the fuel tank 16A, the spring 26A- of the fuel vapor control valve 26A is turned off.
The end of the first evaporation passage 36A is closed by the urging force of No. 6.

Thus, the first chamber 26 of the fuel vapor control valve 26A is connected by the communication means 72A.
A-1 and the second chamber 26A-2 can be communicated, the fuel vapor control valve 26A is closed when the internal combustion engine is stopped and the engine is running, and the fuel and the evaporated fuel in the fuel tank 16A flow into the canister. There is no fear and the canister can be prevented from being deteriorated due to fuel or evaporative fuel, and canister performance can be ensured.

The communication means 72A is connected to the first chamber 26.
The diameter of the orifice 76A does not affect the lubrication performance by forming the orifice 76A in the middle of the communication passage 74A, which is formed by the communication passage 74A connecting the A-1 and the second chamber 26A-2. The aperture diameter can be reduced, which is practically advantageous.

FIG. 4 shows a second embodiment of the present invention. In the second embodiment, portions that perform the same functions as those in the first embodiment will be described with the same reference numerals.

The feature of the second embodiment is that a diaphragm 26B-5 which partitions a first chamber 26B-1 and a second chamber 26B-2 of a fuel vapor control valve 26B provided in a fuel tank 16B is provided. A hole 82B functioning as an orifice is provided, and this hole 82B is
2B.

That is, as shown in FIG. 4, the fuel vapor control valve 26B is connected to the diaphragm 26B-5.
The first chamber 26B-1 and the second chamber 26B-2 are partitioned by the diaphragm 26B-5.
-1 and a second hole 26B connecting the second chamber 26B-2.

Then, after a short time has passed since refueling of the fuel tank 16B, as shown in FIG.
The difference between the oil level in the fuel tank 16B and the oil level in the fuel tank 16B disappears, and the pressure P1 in the first chamber 26B-1 of the fuel vapor control valve 26B and the pressure P in the fuel tank 16B are reduced.
The relationship with 2 is P1 = P2.

That is, the inside of the fuel tank 16B and the first chamber 26B-1 of the fuel vapor control valve 26B are communicated by the hole 82B, and the pressure P1 in the first chamber 26B-1 of the fuel vapor control valve 26B is reduced. The pressure P2 in the fuel tank 16B becomes equal.

At this time, when the pressure P1 in the first chamber 26B-1 of the fuel vapor control valve 26B becomes equal to the pressure P2 in the fuel tank 16B, the first evaporative force of the fuel vapor control valve 26B causes the first evaporative force. The end of the passage 36B is closed.

As a result, the first chamber 26B-1 and the second chamber 26B-2 of the fuel vapor control valve 26B can be communicated with each other. During operation, the fuel vapor control valve 26B is closed, and there is no danger that the fuel or evaporative fuel in the fuel tank 16B will flow into the canister side. Can secure.

Further, a hole 82B functioning as an orifice is provided in a diaphragm 26B-5 for partitioning a first chamber 26B-1 and a second chamber 26B-2 of the fuel vapor control valve 26B. Function as the communication means 72B, the hole 82
The diameter of B can be a throttle diameter which does not affect the lubrication performance, which is practically advantageous.

Further, since it can be dealt with only by forming the hole 82B in the diaphragm 26B-5, there is no fear that the configuration is complicated, the cost can be kept low, and it is economically advantageous.

FIGS. 5 and 6 show a third embodiment of the present invention.

The feature of the third embodiment is that the communication means 72C connects the first chamber 26C-1 and the second chamber 26C-2 of the fuel vapor control valve 26C provided in the fuel tank 16C. The communication passage 74C is provided with an on-off valve 92C that opens during operation of the internal combustion engine in the middle of the communication passage 74C.

That is, as shown in FIGS. 5 and 6, the first chamber 26 of the fuel vapor control valve 26C is provided.
A communication path 74C for connecting C-1 and the second chamber 26C-2 is provided. The communication path 74C is used as communication means 72C, and an on-off valve 92C is provided in the communication path 74C. The control is performed by means to open the on-off valve 92C during operation of the internal combustion engine.

Immediately after refueling the fuel tank 16C, as shown in FIG. 5, a two-way solenoid valve (VS
V), the on-off valve 92C is turned off, and the communication path 74
C is closed.

Further, during the operation of the internal combustion engine, as shown in FIG. 6, the opening / closing valve 92C is turned on by control means (not shown), and the communication passage 74C is opened.

As a result, the first chamber 26C-1 and the second chamber 26C-2 of the fuel vapor control valve 26C can be communicated, and the internal combustion engine can be connected similarly to the first and second embodiments. During stop and operation, the fuel vapor control valve 26C is closed and the fuel tank 16
There is no fear that the fuel or evaporated fuel in C flows into the canister side, so that deterioration of the canister due to the fuel or evaporated fuel can be prevented, and canister performance can be ensured.

The communication means 72C is connected to the fuel vapor control valve 26 provided in the fuel tank 16C.
By having a communication passage 74C that connects the first chamber 26C-1 and the second chamber 26C-2 of C, and having an on-off valve 92C that opens during operation of the internal combustion engine in the middle of the communication passage 74C, The on-off valve 92C can be opened and closed by an existing engine computer.
The opening and closing operation of C can be performed accurately, and fine setting control can be realized, and the reliability of the control can be improved.

FIGS. 7 and 8 show a fourth embodiment of the present invention.

The feature of the fourth embodiment is that the upper part of the fuel tank 16D and the fuel supply pipe 2 of the fuel tank 16D are provided.
This is characterized in that a communication passage 102D communicating with the vicinity of the oil supply side of 0D is provided, and an on-off valve 104D that opens during operation of the internal combustion engine is provided in the middle of the communication passage 102D.

That is, as shown in FIGS. 7 and 8, the upper portion of the fuel tank 16D and the fuel supply pipe 20 of the fuel tank 16D are provided.
A communication passage 102D is provided to communicate with the vicinity of the refueling side of D,
2-way solenoid valve (VSV) in the middle of communication passage 102D
And a control means (not shown) as an engine computer for controlling the opening and closing of the on-off valve 104D during operation of the internal combustion engine.

Immediately after the fuel is supplied to the fuel tank 16D, as shown in FIG.
As a result, the communication passage 102D is closed, and during operation of the internal combustion engine, the open / close valve 104D is turned on by control means (not shown) as shown in FIG. 8, and the communication passage 102D is opened.

As a result, when the internal combustion engine is operating, the on-off valve 10
4D is opened and the upper part of the fuel tank 16D and the fuel tank 1 are opened.
It is possible to communicate with the vicinity of the refueling side of the 6D refueling pipe, and there is no danger that the fuel or evaporative fuel in the fuel tank 16D will flow into the canister when the internal combustion engine is stopped or in operation. Can be prevented and canister performance can be secured.

[0076]

As apparent from the above detailed description, according to the present invention, the internal combustion engine is stopped between the evaporation passage communicating with the fuel tank and the purge passage communicating with the intake passage of the intake system of the internal combustion engine. During the operation of the internal combustion engine, the fuel vapor adsorbed and held by the air introduced from the air communication passage is released and the vaporized fuel sucked from the purge passage is sucked out from the purge passage. A canister for supplying to the passage, a purge valve for controlling the amount of fuel evaporated to the intake passage in accordance with the operation state of the internal combustion engine in the middle of the purge passage, and a float for vertically moving the fuel tank to open and close the evaporative passage according to the fuel amount. The evaporative fuel control device of the internal combustion engine is provided with a valve and a tank internal pressure control valve that opens the evaporative passage when the working pressure from the fuel tank exceeds the set pressure. A fuel vapor control valve is provided in the fuel tank, and the fuel vapor control valve is divided by the diaphragm and the first chamber formed to communicate with the fuel supply pipe near the fuel supply side of the fuel tank. The first chamber and the second chamber of the fuel vapor control valve are formed by the communication means because the first chamber and the second chamber are constituted by the second chamber formed to communicate with the tank and the communication means for communicating the first chamber and the second chamber is provided. When the internal combustion engine is stopped and running, the fuel vapor control valve is closed, and there is no danger of fuel or evaporated fuel in the fuel tank flowing into the canister. The deterioration can be prevented, and the canister performance can be ensured.

Further, between the evaporative passage communicating with the fuel tank and the purge passage communicating with the intake passage of the internal combustion engine, the gas is generated in the fuel tank while the internal combustion engine is stopped, and is guided to the evaporative passage. A canister is provided for adsorbing and holding the evaporated fuel and releasing the evaporated fuel adsorbed and held by the air introduced from the atmosphere communication passage during the operation of the internal combustion engine and supplying the fuel to the intake passage from the purge passage. A purge valve that controls the amount of fuel evaporated to the intake passage according to the operating state is provided.A float valve that moves up and down by the fuel amount to open and close the evaporative passage is provided in the fuel tank. In an evaporative fuel control system for an internal combustion engine equipped with a tank internal pressure control valve that opens the evaporative passage when it becomes large, refueling of the upper part of the fuel tank and the fuel supply pipe of the fuel tank An on-off valve that opens during operation of the internal combustion engine is provided in the middle of the communication passage, and the on-off valve is opened during operation of the internal combustion engine. It is possible to communicate with the vicinity, and there is no fear that fuel or evaporated fuel in the fuel tank will flow into the canister when the internal combustion engine is stopped or running, and it is possible to prevent deterioration of the canister due to fuel and evaporated fuel. Canister performance can be ensured.

[Brief description of the drawings]

FIG. 1 is a schematic view of a fuel tank immediately after refueling, showing a first embodiment of the present invention.

FIG. 2 is a schematic view of a fuel tank immediately after refueling, showing another example of FIG. 1;

FIG. 3 is a schematic view of the running fuel tank after the fuel tank is refueled and becomes full.

FIG. 4 is a schematic view of a fuel tank showing a second embodiment of the present invention.

FIG. 5 is a schematic view of a fuel tank immediately after refueling, showing a third embodiment of the present invention.

FIG. 6 is a schematic view of a fuel tank during operation.

FIG. 7 is a schematic view of a fuel tank immediately after refueling, showing a fourth embodiment of the present invention.

FIG. 8 is a schematic view of a fuel tank during operation.

FIG. 9 is a system configuration diagram of an evaporative fuel control device for an internal combustion engine showing a conventional technique of the present invention.

FIG. 10 is a schematic view of a fuel tank before refueling.

FIG. 11 is a schematic view of a fuel tank during refueling.

FIG. 12 is a schematic view of a fuel tank after refueling.

FIG. 13 is a schematic view of a fuel tank during operation.

FIG. 14 is a schematic view of a fuel tank at the time of a full tank immediately after refueling.

FIG. 15 is a schematic diagram of a running fuel tank after a full tank has been filled immediately after refueling.

[Explanation of symbols]

 16A Fuel tank 18A Refueling cap 20A Refueling pipe (filler hose) 22A Refueling path (filler passage) 26A Fuel vapor control valve 26A-1 First chamber 26A-2 Second chamber 26A-3 Float valve body 26A-4 Housing 26A- 5 Diaphragm 26A-6 Spring 34A Evaporative fuel control device (evaporation system) 36A First evaporation passage 40A Third evaporation passage 72A Communication means 74A Communication passage 76A Orifice

Claims (5)

[Claims] 1. A fuel cell system, comprising: an evaporative passage that is generated in the fuel tank during a stop of the internal combustion engine between an evaporative passage communicating with a fuel tank and a purge passage that communicates with an intake passage of an internal combustion engine. A canister that adsorbs and holds the introduced evaporative fuel and releases the evaporative fuel that is adsorbed and held by the air introduced from the atmosphere communication passage during the operation of the internal combustion engine and supplies the evaporative fuel from the purge passage to the intake passage; In the middle of the purge passage, a purge valve for controlling the amount of fuel vapor to the intake passage according to the operation state of the internal combustion engine is provided, and a float valve for moving the fuel tank up and down to open and close the evaporation passage is provided, In the evaporative fuel control device for an internal combustion engine provided with a tank internal pressure control valve that opens an evaporative passage when the working pressure from the fuel tank becomes larger than a set pressure. A fuel vapor control valve is provided in the fuel tank, and the fuel vapor control valve is formed so as to be communicated with a fuel pipe on the fuel tank, which is defined by a diaphragm, and connected to a fuel supply side of the fuel tank.
A chamber and a second chamber partitioned by a diaphragm and formed to communicate with the canister and the fuel tank;
An evaporative fuel control device for an internal combustion engine, further comprising a communication means for communicating the first chamber and the second chamber. 2. The communication device according to claim 1, wherein the communication means comprises a communication path for connecting the first chamber and the second chamber, and a communication means provided with an orifice in the middle of the communication path. Evaporative fuel control system for an internal combustion engine. 3. The internal combustion engine according to claim 1, wherein said communication means is a communication means which is provided on a diaphragm partitioning the first chamber and the second chamber and comprises a hole functioning as an orifice. Engine fuel vapor control system. 4. The communication means comprises a communication path connecting the first chamber and the second chamber, and an on-off valve provided during the operation of the internal combustion engine in the middle of the communication path. An evaporative fuel control device for an internal combustion engine according to claim 1, wherein 5. A gas generated in the fuel tank between the evaporation passage communicating with the fuel tank and the purge passage communicating with the intake passage of the internal combustion engine during the stop of the internal combustion engine, and formed in the evaporation passage. A canister that adsorbs and holds the introduced evaporative fuel and releases the evaporative fuel that is adsorbed and held by the atmosphere introduced from the atmosphere communication passage during operation of the internal combustion engine and supplies the evaporative fuel from the purge passage to the intake passage; In the middle of the purge passage, a purge valve that controls the amount of fuel vapor to the intake passage according to the operation state of the internal combustion engine is provided, and a float valve that moves up and down by the fuel amount and opens and closes the evaporation passage is provided in the fuel tank, In the evaporative fuel control device for an internal combustion engine provided with a tank internal pressure control valve that opens an evaporative passage when the operating pressure from the fuel tank becomes larger than a set pressure. A communication passage communicating between the upper portion of the fuel tank and the vicinity of a fuel supply pipe of the fuel tank, and an on-off valve that opens during operation of the internal combustion engine is provided in the middle of the communication passage. Fuel control device.