JP2557303Y2 - Evaporative fuel cooling system - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device, and more particularly to a fuel vapor cooling device for cooling and liquefying fuel vapor generated in a fuel tank for an automobile.

[0002]

2. Description of the Related Art Evaporation in which fuel vapor generated in a fuel tank is adsorbed and collected by activated carbon filled in a container, and the vapor collected by intake of an operating engine is introduced into the engine and burned. Fuel processing devices are known. For example,
No. 52-27293 or No. 55-17938
As shown in the above item, an evaporative fuel processing apparatus that cools and condenses steam by a condensing tank or cooling fins provided in a fuel tank, returns the fuel to the fuel tank, and reduces the amount of fuel vapor sent to a container filled with activated carbon It has been known.

[0003]

In a conventional evaporative fuel processing apparatus, almost several hundreds of fuel vapor are generated by adsorbing the evaporative fuel generated when the engine of the vehicle is stopped or parked on activated carbon.
Only gram of activated carbon is filled in the container. However, in addition to when the engine is stopped or parked, the fuel evaporates in the fuel tank of the vehicle even when refueling gasoline or in an environment where the outside air is hot, so a large amount of activated carbon that can adsorb a large amount of fuel vapor is required. is there. As described above, a large amount of activated carbon is required to increase the evaporated fuel processing capacity of the container filled with activated carbon in response to the evaporation of fuel under various driving conditions and environments. For this reason, a large container for accommodating a large amount of activated carbon is also required, which limits the installation space and increases the weight of the vehicle body. Condensation tanks or cooling fins with insufficient cooling cannot condense large amounts of fuel vapor. Accordingly, an object of the present invention is to provide a device capable of reducing the burden on the conventional activated carbon filled container, requiring a minimum container volume, and at the same time maximizing the processing of evaporated fuel.

[0004]

The evaporative fuel cooling apparatus according to the present invention is mounted on a fuel tank (2) and has a first fuel tank.
The first housing (11) provided with the pressure detecting means (71) and a heat storage material (101) which is disposed inside the first housing (11) and reacts exothermically when storing hydrogen and absorbs heat when releasing hydrogen. first first cooler having heat absorbing section (20) and (C _1), attached to the fuel tank separately from the first cooling device (C ₁₎ (2) and a second pressure with A second housing (12) provided with a detecting means (72);
Heat storage material (103) that is disposed inside the housing (12) and reacts exothermically when storing hydrogen and absorbs heat when releasing hydrogen
A second cooler (C ₂ ) having a second heat absorbing portion (40) having a first heat absorbing portion (20) disposed outside the first housing (11); A first heat generating portion (30) having a heat storage material (102) having a lower hydrogen equilibrium pressure than the heat storage material (101) of the first heat absorbing portion (20); and a second housing (12).
The second heat absorbing portion (40) is located outside the
A second heat generating part (50) having a heat storage material (104) having a lower hydrogen equilibrium pressure than the heat storage material (103) of the heat absorbing part (40), a first heat absorbing part (20) and a first heat generating part (30) and a first communication pipe (14) provided with a first on-off valve (16).
A second communication pipe (15) that connects the second heat absorbing section (40) and the second heat generating section (50) and is provided with the second on-off valve (17); and a fuel tank (2). Inlet connected to the inlet pipe (60) through which the fuel vapor generated in the) flows, and the first branch pipe (6)
A switching valve (2) having one outlet connected to the first housing (11) via the second branch and the other outlet connected to the second housing (12) via the second branch pipe (63); 61)
And Detection signals from the first pressure detecting means (71) for detecting the internal pressure in the first housing (11) and the second pressure detecting means (72) for detecting the internal pressure in the second housing (12) are used. Based on the first on-off valve (16) or the second
The control signal is transmitted in synchronization with the on-off valve (17) and the switching valve (61) of the first cooling valve, and the first on-off valve (16) and the second on-off valve (17) are alternately opened and closed to perform the first cooling. The fuel vapor is alternately and continuously cooled by the cooler (C ₁ ) and the second cooler (C ₂ ).

[0005]

The first opening / closing valve (16) or the second opening / closing valve (17) and the switching valve are based on detection signals from the first pressure detecting means (71) and the second pressure detecting means (72). A control signal is transmitted in synchronization with (61) to open and close the first on-off valve (16) and the second on-off valve (17) alternately. As a result, the fuel vapor is transferred from the fuel tank (2) to either the first housing (11) of the first cooler (C ₁ ) or the second housing (12) of the second cooler (C ₂ ). Introduce the first cooler (C ₁ )
And the second cooler (C ₂ ) alternately and continuously cool the fuel vapor. The heat generating portion (30) of the first cooler (C ₁ ) or the heat generating portion (50) of the _second cooler (C ₂ ) is provided outside the first housing (11) and the second housing (12). Due to the arrangement, the heat generating action of the heat storage material (102) of the first heat generating portion (30) and the heat storing material (104) of the second heat generating portion (50) is performed by the first housing (11) and the second housing ( It does not hinder the cooling of the fuel vapor in 12). First cooler (C ₁ ) and second cooler
Other than the alternate cooling by the cooler (C ₂ ), a small part of the fuel vapor generated in the fuel tank (2) is absorbed in the activated carbon filled container.

[0006]

FIG. 1 shows an embodiment of an evaporative fuel cooling apparatus according to the present invention. FIG. 1 shows a cross-sectional view of an evaporative fuel cooling device 1 according to the present invention, which is disposed above or in place of a fuel tank 2 storing gasoline 3 as fuel. The evaporative fuel cooling device 1 has a first cooler C ₁ and a second cooler C ₂ which are arranged one above the other. First cooler C ₁
And the second cooler C ₂ has a flat first housing 11 and a second housing 12 for cooling and liquefying the fuel vapor, and the first housing 11 and the second housing 12 are provided with a heat insulating material therebetween. 13 are vertically stacked. Also, the first
The housing 11 and the second housing 12 are respectively provided with discharge pipes 11a and 12a for returning the liquefied fuel to the fuel tank 2 side.

The lower first cooler C ₁ adjacent to the fuel tank 2 has a first heat absorbing portion 20 housed in the first housing 11 and a _first heat absorber 20 disposed outside the first housing 11. It is composed of one heating section 30. First heat absorbing section 20
Has a case 21 of a relatively thin housing that is disposed to be inclined from one end to the other end in the first housing 11. The case 21 is filled with a heat storage material 101 made of a granular hydrogen storage alloy along the thin section. The first heating unit 30 is the case 3
1 and a heat storage material 102 of a granular hydrogen storage alloy filled in the case 31 and having the same or different characteristics as the heat storage material 101.
And an electric heater 32 disposed in the heat storage material 102. The first heat absorbing section 20 and the first heat generating section 30 are connected to the communication pipe 1.
The communication pipe 14 is opened and closed by the operation of an on-off valve 16 such as an electromagnetic valve provided on the first heat generating unit 30 side between the first heat absorbing unit 20 and the first heat generating unit 30. Communication or cut off.

The upper second cooler C _{2, which} has substantially the same structure as the lower first cooler C ₁ , includes a second heat absorbing portion 40 housed in the second housing 12 and a second heat absorbing portion 40. The second heat generating unit 50 is provided outside the second housing 12. The case 51 of the second heating unit 50 is partitioned from the case 31 of the first heating unit 30 by the heat insulating material 19. Second heat absorbing unit 40 has a casing 41 which inclines from one end to the other in the first cooler C ₁ similarly relatively thin housing the second housing 12 within the. The case 41 is filled with a granular heat storage material 103 of a hydrogen storage alloy along the thin section. The second heat generating unit 50 includes a case 51 and a case 51.
It has a heat storage material 104 of a granular hydrogen storage alloy having the same or different characteristics as the heat storage material 103 and an electric heater 52 disposed in the heat storage material 104. The second heat absorbing section 40 and the second heat generating section 50 are connected by the communication pipe 15,
The operation of the first opening / closing valve 17 such as an electromagnetic valve provided on the side of the second heat generating section 50 opens and closes the communication pipe 15 to allow communication between the second heat absorbing section 40 and the second heat generating section 50. Or shut off.
First housing 11 of first cooler C ₁ and communication pipe 14
The first heat absorbing section 20 communicates with the communication pipe 14 through the filter 18a. Similarly, the connecting portion of the second of the second housing 12 and the communicating pipe 15 of the condenser C ₂ porous filter 18b
Is attached, and each second heat absorbing section 40 communicates with the communication pipe 15 through the filter 18b.

In general, a hydrogen storage alloy (M) has a hydrogen storage action of storing hydrogen H ₂ with an “exothermic reaction” when the hydrogen pressure is higher than the hydrogen equilibrium pressure or the ambient temperature is low, and the hydrogen is lower than the hydrogen equilibrium pressure. When the pressure or the ambient temperature is high, it has a hydrogen releasing action of releasing hydrogen with an “endothermic reaction”. The hydrogen storage alloy M, hydrogen H _2, when the metal hydride MHx, heat and [Delta] H, the reaction of the hydrogen storage alloy is expressed by the following equation, heat absorbing function of the hydrogen storage alloy M is generated by the release of hydrogen H ₂ Can be used for cooling the fuel vapor.

[0010]

[Formula 1] M + H ₂ MHx + △ H

As the metal hydride MHx, the heat storage material 101 of the first heat absorbing section 20 of the first cooler C ₁ is used as MH ₁ , and the heat storage material 103 of the second heat absorbing section 40 of the second cooler C ₂ is used as MHx. expressed in MH _3, the heat storage material 1 of the first of the first heating portion 30 of the cooler C ₁
02 is represented by MH ₂ , and the second heat generating portion 5 of the second cooler C ₂
The heat storage material 104 of 0 is represented by MH ₄ . The heat storage material 101 (MH ₁ ) of the first heat absorbing portion 20 and the heat storage material 102 (MH ₂ ) of the first heat generating portion 30 are excellent in the function of storing hydrogen, for example, MmNi _4.5 Al _0.5 (Mm is misch metal). Is selected. Further, the heat storage material 103 (M
H ₃ ) and the heat storage material 104 (MH ₄ ) of the second heating section 50
For example, LaNi _4.5 Al _{0.5 which} is excellent in the function of heating by an exothermic reaction particularly when hydrogen is absorbed is selected. First cooler C
In _1, the hydrogen pressure P ₂ of hydrogen pressure P ₁ and the heat storage material 102 of the heat storage material 101, the relationship P _1> P ₂ is a material chosen to stand. In the second cooler C _2, the hydrogen pressure P ₄ of the heat storage material 104 and the hydrogen pressure P ₃ of the heat storage material 103 is a material chosen so that the relationship of P _3> P ₄ is satisfied.

In the first cooler C ₁ and the second cooler C ₂ , the same hydrogen storage alloy is used for the heat storage material 101 of the first heat absorption unit 20 and the heat storage material 103 of the second heat absorption unit 40. Is also good. Further, the heat storage material 102 of the first heat generation unit 30 and the heat storage material 104 of the second heat generation unit 50 may be the same hydrogen storage alloy. The first cooler C ₁ and the second cooler C ₂ can be a pair of identical coolers. First heat absorbing section 2
0 heat storage material 101 and heat storage material 103 of second heat absorbing section 40
And the heat storage material 102 and the second heat absorbing portion 5 of the first heat generating portion 30
It is necessary that the relationship between the hydrogen pressure P of the heat storage material 104 of 0 and the heat absorption side> the heat generation side.

A switching valve 61 such as an electromagnetic valve is connected to the first housing 11 through an inlet connected to one inlet pipe 60 through which fuel vapor generated in the fuel tank 2 flows, and a first branch pipe 62. One connected outlet and second branch pipe 6
It has the other outlet connected to the second housing 12 via 3. The switching operation of the valve body 64 of the switching valve 61 connected to the fuel tank 2 via the introduction pipe 60 causes the first cooler C
Any _one of the first housing 11 and the second of the second housing 12 of the cooler C ₂ is connected to the fuel tank 2. In FIG. 1, the inlets of the first branch pipe 62 and the second branch pipe 63 in the first housing 11 and the second housing 12 are indicated by circular broken lines.

A pressure sensor 71 is attached to the first housing 11 of the first cooler C ₁ as first pressure detecting means for detecting an internal pressure in the first housing 11, and a second cooler C ₁ is provided. A pressure sensor 72 is attached to the second housing 12 of C ₂ as second pressure detecting means for detecting the internal pressure of the second housing 12. An internal pressure signal detected by the pressure sensors 71 and 72 is transmitted to a vehicle-mounted cooling control device (CP) (not shown) by a microcomputer.
U), and an operation signal is sent to the electromagnetic on-off valves 16 and 17, the switching valve 61, and the electric heaters 32 and 52 by the output of the cooling control device based on the internal pressure signal. The cooling control device includes a timer circuit for controlling the switching timing of the switching valve 61 having the valve element 64 in addition to the control signal transmitted to the on-off valves 16 and 17.

Next, the operation mode and operation of the evaporative fuel cooling device according to the present invention will be described. When the vehicle is parked or stopped by stopping the engine, when refueling with gasoline, or when traveling in a high temperature environment, the fuel tank 2 Gasoline evaporates to produce fuel vapor. The fuel vapor introduction pipe 60, is introduced into the changeover valve 61 and the first housing 11 of the first cooler C ₁ through the branch pipe 62, the internal pressure of the first housing 11 reaches a predetermined pressure level, The pressure sensor 71 detects the internal pressure of the first housing 11, and this detection signal is sent to the cooling control device. The cooling control device moves the valve body 64 of the switching valve 61 upward to open the branch pipe 62 and shuts off the other branch pipe 63 based on the pressure detection signal, and at the same time, the first branch pipe provided in the communication pipe 14. Heating part 3
An operation signal is sent to the 0-side on-off valve 16 to open the on-off valve 16. When the on-off valve 16 is opened, the first heat absorbing portion 20 and the first heat generating portion 30 of the first cooler C ₁ are in communication with each other, and the first heat absorbing portion 20 is connected to the first cooler C ₁ by the hydrogen pressure (P ₁ > P ₂ ). The hydrogen gas H ₂ stored in the heat storage material 101 of the heat absorbing unit 20 is released, and the released hydrogen moves toward the heat storage material 102 of the first heat generating unit 30 through the communication pipe 14. First heat absorbing section 2
At 0, the inside of the first housing 11 is cooled through the case 21 by the heat absorbing function of the heat storage material 101 by releasing hydrogen. The filled fuel vapor contacts the case 21, is cooled and liquefied, and is returned into the fuel tank 2 from the discharge pipe 11 a.

The cooling control device counts whether the operation of the first cooler C ₁ has passed for a predetermined time or not, and the first heat absorbing section 20 of the first cooler C ₁ causes the first heat absorbing section 20 to release the heat from the heat storage material 101. The cooling by the release of hydrogen is completed, and the heat storage material 10 of the first heat absorbing section 20
When the hydrogen pressures P ₁ and P ₂ of the heat storage material 102 of the first and first heat generating units 30 are equilibrated, the cooling control device sends a switching signal to the switching valve 61 and at the same time, transmits the switching signal to the first heating unit 30. An operation signal is also given to the electric heater 32 of the first embodiment. For this reason, the heat storage material 102 of the first heating unit 30 is heated to increase the hydrogen pressure, and the hydrogen pressures P ₁ and P _{2 change} from the equilibrium state to P ₁ <
Reversed to P _2.

[0017] The operation of the valve body 64 of the cooling control device switching valve 61 receives the switching signal from the first cooler C one branch pipe 62 that corresponds to _one closed, into a second cooler C ₂ The other corresponding branch pipe 63 is opened. Therefore, the fuel vapor generated in the fuel tank 2 passes through the introduction pipe 60 to the second
It is introduced into the second housing 12 of the cooler C _2.
When the internal pressure in the second housing 12 increases due to the fuel vapor, the pressure sensor 72 detects the internal pressure of the second housing 12, and this detection signal is sent to the cooling control device. The cooling control device sends an operation signal to the on-off valve 17 on the side of the second heat generating section 50 provided in the communication pipe 15 based on the pressure detection signal. When the second cooler C ₂ on-off valve 17 is opened, the second heat absorbing portion 40 and the second heating unit 50 is the communicating state, the relationship between the hydrogen pressure (P _3> P _4),
The hydrogen gas H ₂ stored in the heat storage material 103 of the second heat absorption unit 40 is released, and the released hydrogen moves toward the heat storage material 104 of the second heat generation unit 50 through the communication pipe 15. The second heat absorbing section 40 cools the inside of the second housing 12 through the case 41 by the heat absorbing action of the heat storage material 103 due to the release of hydrogen. The filled fuel vapor comes into contact with the case 41, is cooled and liquefied, and is returned into the fuel tank 2 from the discharge pipe 12a.

During the cooling and liquefaction of the fuel vapor by the second cooler C ₂ , the first cooler C ₁ prepares the electric heater 3 in the first heating section 30 as a preparation process for the next cooling.
2 is accelerated by energization, and heat is generated by absorbing hydrogen to further heat the heat storage material 102 to increase the hydrogen pressure P ₂ , and the hydrogen pressures P ₁ and P ₂ are reversed from the equilibrium state to P ₁ <P ₂ .

When the cooling by the second cooler C ₂ is completed, the cooling is performed again by the first cooler C ₁ which is on standby through the preparation process. Thus, the first cooler C ₁
The second cooler C ₂ alternately and continuously cools and liquefies the fuel vapor generated in the fuel tank 2. Therefore, the load of the activated carbon filled in the activated carbon filling container to adsorb the fuel vapor is reduced, and during the alternate cooling of the first cooler C ₁ and the second cooler C ₂ , only a small portion of the fuel vapor is absorbed. Since only the activated carbon-filled container is collected in the activated carbon-filled container, the fuel vapor treatment capacity of the activated carbon-filled container itself is reduced, and a small amount of activated carbon is required.

As shown in FIG. 1, the case 21 of the first heat absorbing portion 20 of the first cooler C ₁ and the case 41 of the second heat absorbing portion 40 of the second cooler C ₂ are inclined. In order to dispose, the fuel vapor cooled and liquefied in the first housing 11 and the second housing 12 adheres to the cases 21, 41, and the discharge pipes 11a,
It becomes easier to flow into 12a.

A pipe for connecting a fuel supply port (not shown) of the fuel tank 2 to the first housing 11 and the second housing 12 of the first cooler C ₁ and / or the second cooler C ₂ . The fuel vapor generated during refueling can be cooled and liquefied by means of (4).

[0022]

As described above, the evaporative fuel cooling system according to the present invention alternately and continuously cools the fuel vapor generated in the fuel tank by the first cooler and the second cooler. Most of the fuel vapor generated in the fuel tank can be cooled. Therefore, the burden of adsorbing fuel vapor on the activated carbon filled container is reduced, and the vessel volume can be reduced to a minimum, and the fuel vapor can be treated to the maximum.

[Brief description of the drawings]

FIG. 1 is a sectional view of an evaporative fuel cooling device showing an embodiment of the present invention.

[Explanation of symbols]

1. Evaporative fuel cooling device, 2. Fuel tank, 11
..The first housing, 12 ..the second housing,
11a, 12a ··· exhaust pipe, 13, 19 ··· heat insulating material, 14 ··· first communication pipe, 15 ··· second communication pipe, 16 ··· first open / close valve, 17 ··· second open / close Valve, C ₁ ··· first cooler, C ₂ ··· second cooler,
20 first heat-absorbing section 40 second heat-absorbing section
30 first heat generating part, 50 second heat generating part, 2
1, 41 ... case, 101, 102, 103, 10
4 ・ ・ Heat storage material, 60 ・ ・ Introduction pipe, 61 ・ ・ Switch valve,
62 first branch pipe 63 second branch pipe
71 ··· Pressure sensor (first pressure detecting means)
A pressure sensor (second pressure detecting means),

Claims (1)

(57) [Scope of request for utility model registration] 1. A first housing (11) attached to a fuel tank (2) and provided with a first pressure detecting means (71) and a hydrogen storage element disposed inside the first housing (11). A first cooler (C ₁ ) having a first heat absorbing portion (20) having a heat storage material (101) that sometimes reacts exothermically and absorbs heat when releasing hydrogen, and from the first cooler (C ₁ ). The second housing (12), which is separately attached to the fuel tank (2) and is provided with the second pressure detecting means (72), is disposed inside the second housing (12), and generates heat when absorbing hydrogen. A second cooler (C2) having a second heat absorbing portion (40) having a heat storage material (103) which reacts and absorbs heat when releasing hydrogen, and which is arranged outside the first housing (11). The heat storage material (10) of the first heat absorbing portion (20) is different from the first heat absorbing portion (20).
A first heat generating portion (30) having a heat storage material (102) having a hydrogen equilibrium pressure lower than that of (1), and a different type from the second heat absorbing portion (40) disposed outside the second housing (12); The heat storage material (10) of the second heat absorbing part (40)
A second heat generating part (50) having a heat storage material (104) having a hydrogen equilibrium pressure lower than that of (3), a first heat absorbing part (20) and a first heat generating part (30) are connected, and First communication pipe (14) provided with an on-off valve (16)
And a second communication pipe (15) communicating the second heat absorbing section (40) and the second heat generating section (50) and provided with a second on-off valve (17).
An inlet connected to an inlet pipe (60) through which fuel vapor generated in the fuel tank (2) flows, and one of the inlets connected to the first housing (11) through a first branch pipe (62). A switching valve (61) having an outlet and the other outlet connected to the second housing (12) via a second branch pipe (63), and detecting an internal pressure in the first housing (11). The first on-off valve (16) or the first on-off valve (16) based on detection signals from the first pressure detecting means (71) and the second pressure detecting means (72) for detecting the internal pressure in the second housing (12). A control signal is transmitted in synchronization with the second on-off valve (17) and the switching valve (61), and the first on-off valve (16) and the second on-off valve (17) are alternately opened and closed.
An evaporative fuel cooling device characterized in that fuel vapor is alternately and continuously cooled by a first cooler (C ₁ ) and a second cooler (C ₂ ).