JP2002221106A - Evaporative fuel adsorbing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporative fuel adsorbing device capable of having proper compatibility of both adsorbing performance and vent performance of an evaporative fuel by an adsorbent such as activated carbon and the like. SOLUTION: A filter 3 serving as the evaporative fuel adsorbing device is formed by holding an activated carbon layer 6 between air permeable sheets 4, 5 of nonwoven fabric, which are pasted together at its peripheral rim parts 4a, 5a. The activated carbon layer 6 is formed by filling a large number of flat and tubular grains of activated carbon, i.e., an assortment of activated carbon 7 having an almost cylindrical shape, activated carbon 8 having the shape of an almost triangular tube, activated carbon 9 having the shape of an almost square tube, and activated carbon 10 having the shape of an almost hexagonal tube. The activated carbon 7 to 10 are disposed by uniformly mixing them, and the adjacent activated carbon 7 to 10 abut each other through the outer periphery of those tubes. There are gaps 11 between the activated carbon 7 to 10. The activated carbon 7 to 10 abut the gas permeable sheets 4, 5 at both end surfaces of those tubes. Each hole 7a to 10a having a similar shape to that of each activated charcoals 7 to 10 is formed in the center of each activated carbon 7 to 10 so that the thickness of the respective tube becomes almost uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adsorbing evaporated fuel, and more particularly to an apparatus for adsorbing evaporated fuel generated in an internal combustion engine mounted on an automobile or the like.

[0002]

2. Description of the Related Art Evaporated fuel (evaporation gas) containing harmful HC is generated from a fuel tank of a vehicle-mounted internal combustion engine (engine). If the evaporated fuel fills the intake passage when the engine is stopped or the like, the fuel becomes over-rich and it becomes difficult to restart the engine at a high temperature.
In addition, the evaporated fuel may flow backward through the intake passage when the engine is stopped, and may be released to the atmosphere. Conventionally, as a device for preventing the filling of the fuel vapor into the intake passage or the release of the fuel to the atmosphere flowing backward through the intake passage, conventionally, the device includes activated carbon that adsorbs the fuel vapor, and is provided between the fuel tank and the intake passage. There is known a canister provided between the filters and a filter including activated carbon, which is installed in an intake path.

In recent years, there has been a demand for an extremely low emission level that minimizes the emission of pollutants into the atmosphere, as in the ultra-low-pollution vehicle emission standards and the evaporative emission control standards. In order to comply with these regulations, in addition to the evaporative fuel transmitted from the fuel tank, the evaporative fuel generated from around the injector and flowing backward through the intake path (such as injector-tight vapor) is surely adsorbed. Need to capture, However, when trying to capture these evaporated fuels with the canister, the size of the canister becomes very large, which is impractical.

[0004] In addition, the filter installed in the intake path has the following problems. That is, the activated carbon is biased in the filter due to the vibration of the vehicle or the like, and an area where the activated carbon is sparsely present is generated. In this region, since the adsorbing capability of the evaporated fuel is significantly reduced, there is a concern that the unadsorbed evaporated fuel is released into the atmosphere. Therefore, in order to keep the activated carbon from moving in the filter, conventionally, measures such as fixing the activated carbon with an adhesive have been taken.

However, when activated carbon is held by an adhesive, the adhesive itself blocks micropores on the surface of the activated carbon,
A new problem arises in that the volatile component of the adhesive is adsorbed to the pores and the adsorption performance of the activated carbon itself is reduced. In this case, it is conceivable to use an adhesive having a low volatile content, but such an adhesive is usually a curing type,
There is a drawback that it is easily peeled off by repeated vibration and cold.

On the other hand, as a filter capable of suppressing the movement of activated carbon without using an adhesive, for example, Japanese Patent Application Laid-Open No.
A filter for a clean room disclosed in JP-A-10-10539 is known. This filter structure is shown in FIG.

That is, this clean room filter 5
In FIG. 1, an activated carbon layer 54 is sandwiched between a nonwoven fabric filter 52 and a metal fiber sheet 53 as shown in FIG. In the activated carbon layer 54, metal fibers 5 are used as a core material.
5 are arranged, and activated carbon 56 is arranged in a gap between the metal fibers 55. The nonwoven fabric filter 52 is a filter for coarse dust conventionally used for air conditioning, and the metal fiber sheet 53 is formed of a material having a gaseous substance removing function.
The metal fibers 55 prevent the entire filter 51 from being deformed and also prevent the activated carbon 56 from being biased.

As shown in FIG. 9 (b), the non-woven fabric filter 52 and the metal fiber sheet 53 have substantially U-shaped needles from both sides. 57 is inserted. A return portion 57a is formed at the tip of the needle 57, and the return portion 57a is entangled with the metal fiber sheet 53 or the fiber of the nonwoven fabric filter 52 on the other side, and the nonwoven fabric filter 52 and the metal fiber sheet 53 are integrated.

[0009]

According to such a filter structure, the movement of the activated carbon can be suppressed without using an adhesive or the like. However, the filter 51 has a shape (loop) for holding the metal fiber 55.
Since the particle size of the activated carbon 56 is smaller than the size of the activated carbon 56, it is necessary to increase the filling rate of the activated carbon 56 in order to maintain the activated carbon 56 without unevenness. When the filter 51 having the increased activated carbon filling rate is installed in a place having a large amount of ventilation per unit time, such as the intake path of the engine, the ventilation resistance is not negligible. In particular, when a large amount of intake air is required, such as when the throttle is fully opened with the accelerator pedal depressed, the effect of the airflow resistance is significant, leading to deterioration in drivability and fuel efficiency due to a decrease in engine output. Become like
Further, in the filter 51, when the metal fiber 55 is deformed, there is a concern that the activated carbon 56 held by the metal fiber 55 is biased due to the deformation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to achieve a favorable balance between the performance of adsorbing evaporative fuel by an adsorbent such as activated carbon and the performance of ventilation. An object of the present invention is to provide an evaporative fuel adsorption device. Another object of the present invention is to provide an evaporative fuel adsorbing apparatus capable of suitably suppressing the deviation of an adsorbent such as activated carbon due to vibration.

[0011]

The means for achieving the above object and the effects thereof will be described below. According to the first aspect of the present invention, in order to prevent the fuel vapor generated in the internal combustion engine from being released to the outside air, the fuel vapor adsorbent having an adsorbent having pores on its surface is held by a permeable sheet. In the apparatus, the gist is that the adsorbent is held by the air permeable sheet while maintaining a space for ensuring air permeability separately from the pores.

According to the present invention, even when the adsorbent is held in close contact with the air permeable sheet, ventilation is ensured through the space maintained by the adsorbent itself. Therefore, even if the bias of the adsorbent is suppressed and the performance of adsorbing the evaporated fuel is secured, the airflow resistance can be suitably reduced.

According to a second aspect of the present invention, in the first aspect of the present invention, the adsorbent is integrally formed in a spiral shape or a lattice shape, and the adsorbent is formed on the breathable sheet while maintaining the same shape. The gist is to be held.

According to the present invention, since the adsorbent is integrally formed in a spiral shape or a lattice shape, there is no possibility that the adsorbent is biased.
And since it ventilates through the space of a spiral shape or a lattice shape, ventilation resistance is reduced suitably.

According to a third aspect of the present invention, in the first aspect of the present invention, the adsorbent is formed in a plurality of types of flat cylindrical shapes, and the plurality of types of the adsorbents formed in the cylindrical shape are formed. Are held by the air-permeable sheet in a state where they are packed two-dimensionally so as to be able to contact each other through the outer periphery of the cylinders.

According to the present invention, the ventilation is performed through the holes of the tubular adsorbent or the gaps between the adsorbents, so that also in this case, the ventilation resistance is suitably reduced. Further, since the adsorbents are formed in a plurality of types and are packed in a plane, a gap between the adsorbents is preferably secured unlike, for example, a case where the adsorbent has a single type of cylindrical shape.

According to a fourth aspect of the present invention, an adsorbent having pores on its surface is held on a gas permeable sheet in order to prevent the fuel vapor generated in the internal combustion engine from being released to the outside air. In the evaporative fuel adsorbing device, the gist is that the adsorbent is held by the gas-permeable sheet in a state where holes provided separately from the pores are regulated by regulating means provided on the gas-permeable sheet. I do.

According to the present invention, since the movement of the adsorbent is regulated by the regulating means, the adsorbent is preferably prevented from being biased by vibration. Further, since the gap between the adsorbents is not filled, ventilation through the gap is also ensured.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, a plurality of the adsorbents are formed in a flat cylindrical shape, and the air-permeable sheet has a plurality of The gist is that the adsorbent is held by the air-permeable sheet in a state where each of the protrusions is inserted into a hole formed as an inner circumference of the cylinder of the adsorbent.

According to the present invention, the protrusion is inserted into the hole of the adsorbent to support the adsorbent. Therefore, the adsorbent is accurately prevented from being biased due to vibration. Further, since the gap between the adsorbents is not filled, ventilation through the gap is also ensured.

According to a sixth aspect of the present invention, in the fourth aspect of the present invention, a plurality of the adsorbents are formed in a cylindrical shape, and the air-permeable sheet serves as the restricting means at both ends of a peripheral edge of a surface thereof. The gist is that a plurality of fixed yarns are provided, and the adsorbent is held by the breathable sheet in a state where a plurality of the tubular adsorbents are connected by each of the yarns.

According to the present invention, the yarn is inserted into the hole of the adsorbent to support the adsorbent. Therefore, in this case, the bias of the adsorbent at least in a direction perpendicular to the yarn is prevented. In addition, since the gap between the adsorbents in that direction is not filled, ventilation can be suitably secured.

According to a seventh aspect of the present invention, the adsorbent for adsorbing the evaporated fuel is held on a gas permeable sheet in order to prevent the evaporated fuel generated in the internal combustion engine from being released to the outside air. In the evaporative fuel adsorbing device, the gist is that the adsorbent is held in the air-permeable sheet in a state where a large number of adsorbents are connected to each other in a plane.

According to the present invention, since the adsorbents are entangled with each other to maintain the connected state, the bias of the adsorbents is preferably prevented. And ventilation is suitably ensured through the gap between the adsorbents in the connected state.

According to an eighth aspect of the present invention, in the invention of the seventh aspect, the adsorbent has a hook portion at a tip portion thereof, and the hook portions are entangled with each other to maintain the connected state. Make a summary.

According to this invention, the adsorbent is connected by the entanglement of the hook portions, so that the invention of claim 7 can be easily realized. According to a ninth aspect of the present invention, in order to prevent the fuel vapor generated in the internal combustion engine from being released to the outside air, the fuel adsorbent for adsorbing the fuel vapor is held by a permeable sheet. In the device,
The gist of the invention is that the breathable sheet includes a hook-and-loop fastener portion, and the adsorbent is sandwiched between the hook-and-loop fastener portions.

According to the present invention, since the adsorbent is held by the relatively simple structure of the hook-and-loop fastener structure, the bias of the adsorbent is easily and accurately prevented. According to a tenth aspect of the present invention, in the first aspect of the present invention, the adsorbent is made of activated carbon.

According to the present invention, the invention described in any one of claims 1 to 9 can be easily realized. Also, the adsorption performance is kept high. In addition, when these evaporated fuel adsorbing devices are arranged on the side of the internal combustion engine with respect to the air cleaner element, the effect becomes more remarkable. That is, when the internal combustion engine is operating, the intake air from the outside air is purified by the air cleaner element, and the purified intake air is ventilated through the space, hole or gap between the adsorbents held by the adsorbent. . At that time, the evaporated fuel adsorbed by the adsorbent is blown off, and the adsorbent adsorption ability is restored. Therefore,
The evaporated fuel can be efficiently adsorbed without polluting the air cleaner element with the evaporated fuel.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which an evaporative fuel adsorbing device according to the present invention is embodied in the filter will be described below with reference to FIGS.

As shown in FIG. 2, an intake pipe 1 which is a part of an intake path of an engine as an internal combustion engine of an automobile or the like includes:
An enlarged diameter pipe portion 1a for arranging an air cleaner is formed in the middle of which the diameter is increased. Hereinafter, the pipe portion of the intake pipe 1 on the engine side from the enlarged-diameter pipe portion 1a is referred to as an engine-side pipe portion 1b, and the pipe portion on the atmosphere side is referred to as an atmosphere-side pipe portion 1c. The atmosphere side pipe 1c is communicated with the atmosphere. Engine side tube 1b
Is connected to a fuel tank via a purge passage, a canister, and the like (not shown), and is also connected to a portion near an intake port to which an injector is attached (neither is shown).

On the other hand, an air cleaner element 2 is disposed in the enlarged diameter pipe portion 1a so as to cover the passage. And, the engine side pipe 1 from the air cleaner element 2
On the b side, a filter 3 as an evaporative fuel adsorption device is disposed so as to cover the passage.

Here, this filter 3 is composed of the filter 3 shown in FIG.
As shown in (b), an activated carbon layer 6 made of granular activated carbon is sandwiched between two air-permeable sheets 4 and 5 such as a nonwoven fabric bonded together.

The air permeable sheets 4 and 5 are attached to each other at the peripheral portions 4a and 5a. The activated carbon layer 6 is accommodated in a bag-shaped space formed by the breathable sheets 4 and 5. Further, as shown in FIG. 1 (c), the granular activated carbon constituting the activated carbon layer 6 is formed in a flat substantially cylindrical shape or a substantially polygonal cylindrical shape. That is, the activated carbon layer 6 is formed by packing a large number of activated carbons 7 having a substantially cylindrical shape, activated carbons 8 having a substantially triangular shape, activated carbons 9 having a substantially rectangular shape, and activated carbons 10 having a substantially hexagonal shape. The activated carbons 7 to 10 are arranged almost uniformly. The adjacent activated carbons 7 to 10 are in contact with each other through the outer periphery of the cylinder, and a gap 11 exists between the activated carbons 7 to 10. The activated carbons 7 to 10 are in contact with the breathable sheets 4 and 5 at both end surfaces of the cylinder.

At the center of each of the activated carbons 7 to 10, holes 7a to 10a similar in shape to the respective activated carbons 7 to 10 are formed, and the activated carbons 7 to 10 are formed to have a substantially uniform wall thickness. Next, the operation of the filter 3 configured as described above will be described.

When the engine is stopped, oil-tight vaporized fuel that flows back through the intake pipe 1 from the fuel tank, the intake port provided with the injector, etc., passes through the engine side pipe 1b and enters the enlarged diameter pipe 1a. And reaches the filter 3. Since the above-described activated carbon layer 6 is formed on the filter 3, the activated carbon 7 to 1 constituting the activated carbon layer 6 is formed.
At 0, the fuel vapor is adsorbed. That is, emission of the fuel vapor to the atmosphere is prevented. Incidentally, the activated carbons 7 to 10 have pores on the surface thereof for improving the adsorption rate of the evaporated fuel.

When the engine is running, the accelerator pedal is depressed, the throttle (not shown) is opened, and the intake air flowing into the enlarged diameter pipe section 1a from the atmosphere side pipe section 1c is removed by the air cleaner element 2 as dust. And other small substances are filtered and cleaned. The purified intake air flows into the intake port portion of the engine through the filter 3. In the filter 3, as described above, the holes 7a to 1
Since ventilation is ensured by 0a or the gap 11,
The intake resistance does not increase. In addition, at the time of this passage, the evaporated fuel adsorbed on the activated carbons 7 to 10 is blown off by the intake air, and the adsorption ability of the activated carbons 7 to 10 is restored.

As described above, according to this embodiment, the following effects can be obtained. (1) Since the holes 7a to 10a are formed in the activated carbons 7 to 10, the intake air passes through the holes 7a to 10a, and the suction is performed smoothly. Therefore, the adsorption performance of the fuel vapor is maintained, and the ventilation performance is also maintained.

(2) Since the activated carbons 7 to 10 are formed in a plurality of types of cylindrical shapes such as a cylindrical shape and a polygonal cylindrical shape, one type of activated carbon, for example, a triangular cylindrical activated carbon 7
Unlike the case where only the activated carbon is used, the possibility that the activated carbon is aligned in a predetermined arrangement due to the vibration of the vehicle and the like and the activated carbon is biased in one direction to reduce the possibility that the activated carbon is biased.

(3) The activated carbons 7 to 10 have a plurality of cylindrical shapes, and the activated carbon is not biased by vibration, so that the gap 11 does not collapse. That is, even with such a shape of the activated carbon, the above-mentioned ventilation performance is suitably secured.

(4) Activated carbon 7-1 without using an adhesive
Since the bias of 0 is prevented, the adhesive is not embedded in the pores of the activated carbon, and the volatile components of the adhesive are not adsorbed by the activated carbon, and the adsorption performance of the activated carbons 7 to 10 can be maintained high. .

(5) Since the holes 7a to 10a are formed in a shape similar to the activated carbons 7 to 10, the thickness of the cylinder of the activated carbons 7 to 10 is made substantially uniform, and the passages are maintained while maintaining the strength of the activated carbons 7 to 10. Holes 7a to 10a can be formed widely, and the intake resistance can be further reduced.

(6) Since the filter 3 is disposed closer to the engine side pipe portion 1b than the air cleaner element 2,
During operation of the engine, intake air from outside air is purified by the air cleaner element 2, and the purified intake air is ventilated through the holes 7 a to 10 a or the gap 11. At this time, the evaporated fuel adsorbed on the activated carbons 7 to 10 is blown off, and the adsorption ability of the activated carbons 7 to 10 is restored. Therefore, the evaporative fuel is efficiently removed by the filter 3 without polluting the air cleaner element 2 with the evaporated fuel. Can be adsorbed well.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG. In this embodiment, the activated carbon layer 6
Is different from that of the above embodiment. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, as shown in FIGS. 3A and 3B, a large number of flat activated carbons 20 formed so as to have a substantially cross shape in plan view are combined to form an activated carbon layer 6. It is configured. Activated carbon 20 has a cross-shaped tip bent back to form a hook portion 20a.

The activated carbon layer 6 is formed by connecting the hook portions 20a in a key shape and arranging the activated carbon 20 in a lattice shape. The intake air passes through gaps 21 between activated carbons 20 arranged in a lattice.

According to this embodiment, the following effects can be obtained in addition to the effects (4) and (6) of the above-described embodiment. (7) Since the intake air passes through the gap 21, the ventilation performance is suitably ensured.

(8) Since the activated carbons 20 are arranged by connecting the hook portions 20a, there is no possibility that the activated carbons are biased. (9) Unlike the activated carbons 7 to 10, the activated carbon layer 6 is composed of one type of activated carbon 20;
In contrast to the case of producing, the productivity of activated carbon is improved.

Third Embodiment Next, a third embodiment will be described with reference to FIG. This embodiment is different from the above embodiment in the structure for mounting activated carbon. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, as shown in FIG. 4 (a), the peripheral portions 4a,
A substantially cylindrical activated carbon 22 that is shorter by 5a is formed, and the activated carbon 22 is cut into a predetermined length to form an activated carbon 23. Then, as shown in FIG. 4B, a thread 24 having a length substantially equal to the length of one side of the breathable sheets 4 and 5 is inserted into the activated carbon 23, and the thread 24 provided with the activated carbon 23 is passed through the breathable sheet 4. Place on top. A number of pairs of the same activated carbon 23 and thread 24 are formed and arranged so as to cover the breathable sheet 4. next,
The air permeable sheet 5 is attached to the air permeable sheet 4 so as to sandwich the activated carbon 23 and the thread 24. Both ends 24a of each thread 24
Are attached together with the peripheral portions 4a and 5a of the breathable sheets 4 and 5. The intake air is the gap 25 between the activated carbons 23
Pass through. FIG. 4B shows the activated carbon 23 for the filter 3 so that the whole image of the filter 3 can be easily imaged.
Is enlarged and shown.

According to this embodiment, the following effects can be obtained in addition to the effects (4), (6), (7) and (9) of the above embodiment. (10) Since the movement of the activated carbon 23 in the vertical direction with respect to the yarn 24 is regulated by the yarn 24, it is possible to prevent at least the bias of the activated carbon 23 in the vertical direction. In the direction parallel to the yarn 24, it is prevented from being deviated by at least the total distance between the activated carbons 23 in this direction.

(11) Activated carbon 8 used in the previous embodiment
Activated carbon 23 can be easily manufactured because the shape of activated carbon 23 is simpler than that of activated carbon 20. (Fourth Embodiment) Next, a fourth embodiment will be described with reference to FIG. This embodiment is different from the above embodiment in that a mounting needle is inserted through activated carbon. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, as shown in FIGS. 5A and 5B, a mesh-shaped air-permeable sheet 26 formed in a lattice shape is used. Then, the breathable sheet 26
Needles 27 are formed in each of the lattice point portions in the shape of a sword so as to extend in a direction perpendicular to the air-permeable sheet 26.
The tip of the needle 27 is bent into a hook shape,
7a are formed. The activated carbon 7 is inserted through the needle 27,
It is attached in the form of being hooked by a hook portion 27a so as not to come off. And the breathable sheet 26
The activated carbon 7 is sandwiched between the mesh-shaped air-permeable sheets 4 and 5. Since the activated carbon 7 is inserted through the needle 27, the activated carbon 7 is regulated so as not to move in the plane direction of the breathable sheet 26. In addition, since the activated carbon 7 is sandwiched between the permeable sheets 4 and 5, the activated carbon 7 is regulated so as not to move in a direction perpendicular to the permeable sheet 26. The intake air passes through the gap 28 between the activated carbons 7.

According to this embodiment, (1), (4), (6), (7), (9) and (11) of the above-mentioned embodiment are used.
The following effects can be obtained in addition to the effects described above. (12) Since the activated carbon 7 is inserted and held in the needle 27, it is more securely held than in the above case,
Since the activated carbons 7 do not need to contact each other, the gap 28 can be more easily secured.

(13) Interval of forming needles 27 and activated carbon 7
The ventilation performance can be easily adjusted by changing the diameter of the gap and adjusting the area of the gap 28. (Fifth Embodiment) Next, a fifth embodiment will be described with reference to FIG. This embodiment is different from the above embodiment in the structure of a breathable sheet to which activated carbon is attached. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, as shown in FIGS. 6A and 6B, a large number of cup-shaped projections 31a and 32a are formed so as to face the air permeable sheets 31 and 32, respectively. Activated carbon 33, which is granular and has a large diameter relative to the thickness of the breathable sheets 31 and 32, is stored in the spaces inside the recesses 31b and 32b formed by forming the projections 31a and 32a. Peripheral portions are attached to the breathable sheets 31 and 32, and the flat portions 31 c and 3 between the activated carbons 33 are further attached.
2c is adhered at a predetermined location and integrated. The intake air passes through the flat portions 31c and 32c.

According to this embodiment, the following effects can be obtained in addition to the effects (4), (6), (9) and (11) of the above embodiment. (14) Since the activated carbon 33 is housed in the space formed by the concave portions 31b and 32b, the activated carbon 33 is securely held, and there is no possibility of bias.

(15) The intake air is supplied to the flat plate portions 31c and 32c.
, The ventilation performance is also ensured. (16) Interval of forming the protrusions 31a and 32a and activated carbon 3
The ventilation performance can be easily adjusted by changing the particle size of No. 3 and adjusting the area of the flat plate portions 31c and 32c.

(Sixth Embodiment) Next, a sixth embodiment will be described with reference to FIG. This embodiment is different from the above-described embodiment in that the activated carbon is disposed on the breathable sheet. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, as shown in FIG. 7A, spiral activated carbon 36 is formed integrally and sandwiched between air permeable sheets 4 and 5. In addition, as shown in FIG. 7B, a grid-like activated carbon 37 is integrally formed and sandwiched between the permeable sheets 4 and 5. Activated carbon 3
It passes through openings 38 and 39 as spaces between 6 and 37.

According to this embodiment, the following effects can be obtained in addition to the effects (4), (6), (9) and (11) of the above embodiment. (17) Since the intake air passes through the openings 38 and 39,
The ventilation performance is properly secured.

(18) The ventilation performance can be easily adjusted by adjusting the areas of the openings 38 and 39. (19) Since the activated carbons 36 and 37 are formed integrally, there is no bias.

(20) Since the activated carbons 36 and 37 are integrally formed, the activated carbon 3
The entire 6,37 can be supported, and handling is simplified. (Seventh Embodiment) Next, a seventh embodiment will be described with reference to FIG. This embodiment is different from the above embodiment in the structure of a breathable sheet for holding activated carbon. The same parts as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, as shown in the cross-sectional structure of FIG. 8, the breathable sheets 41 and 42 are provided with a hook-and-loop fastener (so-called magic tape (registered trademark)). That is, the permeable sheet 41 has a large number of ring portions 41a, and the permeable sheet 42 has a large number of hook portions 42a. The activated carbon 43 having a smaller diameter than the ring portion 41a and the hook portion 42a is arranged on the ring portion 41a and the hook portion 42a. Activated carbon 43
Are arranged so as to have a lower density than the conventional activated carbon 56 illustrated in FIG. Then, the permeable sheets 41 and 42 are attached by engaging the ring portion 41a and the hook portion 42a. The intake air passes through the gap between the activated carbons 43.

According to this embodiment, the following effects can be obtained in addition to the effects (4), (6), (7), (9) and (11) of the above embodiment. (21) The activated carbon 43 includes the ring portion 41a and the hook portion 42a.
And bias is prevented. In particular, in the conventional filter 51 illustrated in FIG. 9, unlike the state where the metal fibers 55 are not directly connected to the nonwoven fabric filter 52 and the metal fiber sheet 53, the ring portion 41a and the hook portion 42a , 42, the ring portion 41a and the hook portion 42a are not biased with respect to the breathable sheets 41, 42, and the bias of the activated carbon 43 is also prevented.

(22) Ring 41a and Hook 42a
The air permeable sheets 41 and 42 are detached and attached by the engagement of, so that the air permeable sheets 41 and 42 can be easily attached and detached. Note that the embodiments are not limited to the above embodiments, and may be modified as follows, for example.

In the first embodiment, the activated carbon is not limited to being formed in a cylindrical shape or a tri-hexagonal tube shape, but may be formed in another polygonal tube shape, a semi-cylindrical shape, or the like. In the first embodiment, the activated carbon is not limited to being formed in a cylindrical shape. For example, a cutout may be formed in the side surface of the activated carbon tube so that the shape in a plan view becomes a C shape. Good.

In the first embodiment, the holes 7a-10
a is not limited to being formed in a similar shape to each of the activated carbons 7 to 10. For example, all the holes may be formed in a circular shape.

In the first embodiment, the activated carbon 8 to 1
Of the activated carbons having a polygonal cylindrical shape such as 0, only one type of activated carbon may be closely packed so that no gap is formed between the activated carbons. Even in this case, since the intake air passes through the hole of the cylinder, the ventilation performance is ensured.

In the second embodiment, the hook portion 20
In order to make the hooks 20a more easily connected to each other, the length of the folded portion is further increased so that the tip of the hook portion 20a reaches the vicinity of the center of the cross of the activated carbon 20.
a may be formed.

In the fourth embodiment, instead of the activated carbon 7, activated carbons 8 to 10 or other flat cylindrical activated carbons may be inserted through the needle 27. -In 5th Embodiment, not only activated carbon 33 but for example activated carbon 7-10 may be accommodated in recessed part 31b, 32b.

In the sixth embodiment, the activated carbon is not limited to being formed in a spiral or lattice shape. For example, the activated carbon may be formed in a plurality of rings, and the rings may be arranged concentrically.

In the seventh embodiment, not only the activated carbon 43 but also activated carbons 7 to 10 are packed as in the first embodiment, and all or a part of the ring portion 41a or the hook portion 42a is formed by the gap 11 or the hole. 7a to 10a may be inserted, and the inserted ring portion 41a and hook portion 42a may be engaged. In this case, the ring portion 41a and the hook portion 42a need not be inserted into all the holes 7a to 10a.

The air permeable sheets 4 and 5 are not limited to being formed of a nonwoven fabric, but may be formed of, for example, other air permeable cloth or paper. The bonding of the air permeable sheets 4 and 5 is not limited to welding, but may be performed by, for example, engaging and attaching by a snap-fit structure, inserting and fixing a substantially U-shaped needle (a so-called stapler or the like), or expanding the diameter. It may be fixed by being sandwiched between the tube portions 1a.

The adsorbent is not limited to activated carbon, and other adsorbents may be used. The location of the filter 3 is not limited to the location shown in FIG.
The fuel vapor can be arranged in any form at any place where the outflow of fuel vapor into the atmosphere can be prevented.

The technical ideas that can be grasped from the above embodiments will be additionally described below. (1) In the evaporative fuel adsorbing device in which an adsorbent for adsorbing the evaporative fuel is held on a permeable sheet in order to prevent the evaporative fuel generated in the internal combustion engine from being released to the outside air, An evaporative fuel adsorbing device, wherein a concave portion is formed on each of the opposite surfaces of the sheet, and the adsorbent is held in the concave portion.

(2) In the first aspect of the present invention, the activated carbon is formed in a flat cylindrical shape, and the activated carbon is arranged so that the direction of the hole is the same as the direction of the ventilation, and the activated carbon is spread over one layer. The matched activated carbons are in contact with each other.

(3) Claims 1 to 10, (1)
In the invention described in any one of (2) and (2), the air permeable sheet is a mesh air permeable sheet.

(4) The invention according to any one of claims 1 to 10 and (1) to (3), wherein the air-permeable sheet is a nonwoven fabric.

[Brief description of the drawings]

FIG. 1 shows a fuel vapor adsorption device according to a first embodiment,
(A) is a schematic perspective view of a filter, (b) is a schematic exploded perspective view, and (c) is an enlarged schematic plan view of a main part of an activated carbon layer.

FIG. 2 is a schematic cross-sectional view of a main part showing a ventilation pipe.

FIG. 3 shows an evaporative fuel adsorption device according to a second embodiment,
(A) is a schematic diagram showing activated carbon, and (b) is a schematic plan view of a main part showing a connected state of the activated carbon in (a).

FIG. 4 shows a fuel vapor adsorption device according to a third embodiment,
(A) is a schematic diagram showing activated carbon, and (b) is a schematic plan view showing an attached state of the activated carbon of (a).

FIG. 5 shows a fuel vapor adsorption device according to a fourth embodiment;
(A) is a schematic exploded perspective view showing a mounting structure of activated carbon,
(B) is a principal part schematic sectional view showing an attached state.

FIG. 6 shows a fuel vapor adsorption device according to a fifth embodiment;
3A is a schematic perspective view of a main part of the filter, and FIG. 3B is a cross-sectional view taken along line BB of FIG.

FIG. 7 shows a fuel vapor adsorption device according to a sixth embodiment;
(A) is a schematic perspective view of a main part of a filter including spiral activated carbon, and (b) is a schematic perspective view of a main part of a filter including lattice-shaped activated carbon.

FIG. 8 is a schematic cross-sectional view of a main part showing an evaporative fuel adsorption device according to a seventh embodiment.

9A is a schematic cross-sectional view of a main part showing a conventional filter, and FIG. 9B is a schematic cross-sectional view of a main part showing a mounting structure.

[Explanation of symbols]

2 ... air cleaner element, 3 ... filter as evaporative fuel adsorbing device, 4, 5, 26, 41, 42 ... permeable sheet, 4a, 5a ... peripheral part, 7 to 10, 20, 23, 3
6, 37, 43 ... activated carbon, 7a to 10a ... holes, 20a ...
Hook part, 24 ... thread, 24a ... end part, 27 ... needle as projection, 38, 39 ... opening part as space, 41a ... ring part which constitutes a surface fastener part, 42a ... same hook part.

Continued on the front page (72) Inventor Anjo Takayama 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3G044 BA20 EA05 GA12

Claims (10)

[Claims] 1. An evaporative fuel adsorber comprising an adsorbent having pores on its surface held by a permeable sheet in order to prevent evaporative fuel generated in an internal combustion engine from being released to the outside air. The evaporative fuel adsorbing device, wherein the adsorbent is held by the air permeable sheet while maintaining a space for ensuring air permeability separately from the pores. 2. The evaporative fuel adsorbing device according to claim 1, wherein the adsorbent is integrally formed in a spiral shape or a lattice shape, and is held by the air permeable sheet while maintaining the same shape. 3. The adsorbent is formed in a plurality of flat cylindrical shapes, and the plurality of adsorbents formed in the cylindrical shape are flatly packed so as to be in contact with each other through the outer periphery of the cylinder. The evaporated fuel adsorbing device according to claim 1, wherein the device is held by the air permeable sheet in a slid state. 4. An evaporative fuel adsorbing apparatus in which an adsorbent having pores on its surface is held by a gas permeable sheet in order to prevent evaporative fuel generated in the internal combustion engine from being released to the outside air. An evaporative fuel adsorbing device wherein the adsorbent is held by the air-permeable sheet in a state where holes provided separately from the pores are regulated by regulating means provided on the air-permeable sheet. 5. A plurality of said adsorbents are formed in a flat cylindrical shape, and said breathable sheet is provided with a plurality of projections as said regulating means on a surface thereof, and each of said projections is an inner circumference of said adsorbent. 5. The evaporative fuel adsorbing device according to claim 4, wherein the adsorbent is held by the air permeable sheet while being inserted into the hole formed as. 6. A plurality of said adsorbents are formed in a cylindrical shape, and said breathable sheet is provided with a plurality of yarns, both ends of which are fixed to a peripheral portion of a surface thereof, as said restricting means, and said yarn is formed by each of said yarns. The evaporative fuel adsorbing device according to claim 4, wherein the adsorbent is held by the air-permeable sheet in a state where a plurality of adsorbents are connected. 7. An evaporative fuel adsorbing apparatus in which an adsorbent for adsorbing the evaporative fuel is held on a permeable sheet to prevent the evaporative fuel generated in the internal combustion engine from being released to the outside air. An evaporative fuel adsorbing device characterized in that the adsorbent is formed in a shape that is entangled with each other and is held by the air permeable sheet in a state of being connected in a large number in a plane. 8. The evaporative fuel adsorbing device according to claim 7, wherein the adsorbent has a hook portion at a tip portion thereof, and the hook portions are entangled with each other to maintain the connected state. 9. An evaporative fuel adsorber, wherein an adsorbent for adsorbing the evaporative fuel is held on a permeable sheet in order to prevent the evaporative fuel generated in the internal combustion engine from being released to the outside air, The air-permeable sheet is provided with a hook-and-loop fastener portion, and the adsorbent is sandwiched between the hook-and-loop fastener portions. 10. The method of claim 1, wherein said adsorbent comprises activated carbon.
The evaporative fuel adsorption device according to any one of claims 9 to 9.