JP2000257516A - Canister for disposal of fuel vapor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a canister for disposal of a fuel vapor capable of being miniaturized by reducing a thickness of a plate for pressing an adsorbent while ensuring the strength of the plate and suppressing ventilation resistance inside the canister to a low value. SOLUTION: This canister 10 is provided with a case main body 12, an adsorbent 14 stored in the case main body 12, a ventilating filter 21 which is inserted into the inside of the case main body 12 and covers a lower part of the adsorbent 14, and a plate 22 inserted into the case main body 12 by overlapping on the filter 21. The adsorbent 14 is divided into a plurality of layers 14A, 14B by a partitioning wall 12b, and a connection passage 24 allowing the ventilation between a plurality of layers 14A and 14B is provided between a tip of the partitioning wall 12b and the filter 21. A ventilation passage 35 which recedes in the direction of thickness of the plate 22 from a contact face with the filter 21 to allow the ventilation between a plurality of layers 14A and 14B is provided on the plate 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a canister for treating steam generated in a fuel tank of a vehicle.

[0002]

2. Description of the Related Art As a canister for treating fuel vapor of a vehicle, for example, as shown in FIG. 4, an adsorbent 2 filled in a case 1 is passed through a filter 3 and a plate 4 mounted from the open end of the case 1. There is a structure having a structure in which the spring 5 presses down. The adsorbent 2 is divided into a first layer 2A and a second layer 2B by a partition wall 1a, and a communication path 6 is provided between the partition wall 1a and the filter 3 to allow ventilation between the two layers 2A and 2B. ing. Further, a large number of through holes 4a... 4a are formed in the plate 4, and the spring chamber 7 functions as a fuel vapor diffusion chamber (see Japanese Patent Application Laid-Open No. 9-88739). Further, as shown in FIG. 5, there is a case where the spring chamber 7 does not function as a diffusion chamber by using a metal plate 4 'having no through hole.

[0003]

In the canister shown in FIG. 4, the fuel vapor that has passed through either the first layer 2A or the second layer 2B is sufficiently diffused in the spring chamber 7 and the first layer 2A
Alternatively, since the air is guided to either one of the second layers 2B, the airflow resistance between the two layers is reduced, and the length of the partition wall 1a is increased, so that the processing capability of the fuel vapor can be increased. However, since the plate 4 has a large number of through holes 4a, the strength is low, and it is necessary to form the plate 4 thick to compensate for this. For this reason, the total height of the canister increases, which may cause inconvenience in the layout.

On the other hand, in the canister shown in FIG.
Since there is no through-hole, sufficient strength can be ensured even if the plate 4 'is thin. However, the first layer 2A and the second layer 2
Since the ventilation with B is performed only through the communication path 6, the ventilation resistance is high, and the processing performance of the fuel vapor is inferior.

Accordingly, the present invention provides a fuel vapor which can reduce the thickness of the plate while securing the strength of the plate for holding down the adsorbent, thereby reducing the size of the canister and suppressing the ventilation resistance inside the canister. The purpose of the present invention is to provide a canister.

[0006]

Hereinafter, the present invention will be described. In addition, in order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are added in parentheses, but the present invention is not limited to the illustrated embodiment.

According to the first aspect of the present invention, there is provided a cylindrical case body (12) having an open end, an adsorbent (14) contained in the case body (12), and the one end of the case body (12). A permeable filter (21) inserted into the case body from above to cover the adsorbent (14), and a plate (22) inserted into the case body (12) so as to overlap the filter (21). The adsorbent (14) is supplied from the wall (12a) at the other end of the case body (12) to the filter (2).
The partition wall (12b) extending toward 1) is divided into a plurality of layers (14A, 14B), and the plurality of layers (14) are disposed between the tip of the partition wall (12b) and the filter (21).
A, 14B) are provided with a communication path (24) which allows ventilation between the layers, and the plate (22) is receded in the thickness direction of the plate (22) from the contact surface with the filter (21) to form the plurality of layers. (14A, 14B) ventilation path (3
The problem described above is solved by the fuel vapor treatment canister provided with (5).

According to the present invention, the fuel vapor can move between the first layer and the second layer through the air passage on the plate (22), so that there is no need to provide a through hole in the plate (22). Alternatively, even if necessary, the number can be significantly reduced as compared with the conventional case. Therefore, sufficient strength can be obtained even if the plate is thinned, thereby increasing the canister (1).
0) can be reduced in size. In addition, since the ventilation path (35) is secured in addition to the communication path (24) between the partition wall (12b) and the filter (21), the ventilation resistance inside the canister (10) can be suppressed low. . Vent (3
The state of the flow of the fuel vapor between the first layer and the second layer can be freely set according to the shape and arrangement of 5).

According to a second aspect of the present invention, in the canister (10) for treating a fuel vapor according to the first aspect, the plate (22) has airtightness in a thickness direction. In this case, the strength of the plate (22) is further increased, and a thinner plate (22) can be realized.

According to a third aspect of the present invention, in the canister (10) for treating fuel vapor according to the first or second aspect, the contact surface side of the plate (22) is divided into a plurality of spaces. A plurality of ribs (33 ... 33) for partitioning are provided, and a plurality of recesses (33a) recessed in the thickness direction of the plate (22) are provided on the ribs (33 ... 33). The space (34) and the recess (33a) communicate with each other to form a ventilation path (35).
According to this, while keeping the ventilation resistance of the canister low, a plurality of ribs (3) provided on the plate (22) are provided.
According to 3), the strength of the plate (22) can be easily increased.

[0011] As in the fourth aspect of the present invention, the first aspect
When the plate (22) according to any one of the first to third aspects is formed of resin, the plate (22) can be easily and inexpensively manufactured by injection molding of the resin.

According to a fifth aspect of the present invention, there is provided a cylindrical case body (12) having an open end, an adsorbent (14) contained in the case body (12), and the one end of the case body (12). A permeable filter (21) inserted into the case body from above to cover the adsorbent (14), and a plate (22) inserted into the case body (12) so as to overlap the filter (21). The adsorbent (14) is supplied from the wall (12a) at the other end of the case body (12) to the filter (2).
A plurality of layers (14A, 14B) are divided by a partition wall (12b) extending toward 1), and a plurality of layers (14A, 1B) are provided between the tip of the partition wall (12b) and the filter (21).
A communication path (35) is provided to allow ventilation between 4B) and
Ribs (33... 33) are provided on the side of the plate (22) in contact with the filter (21).
In 3), the above-described problem is solved by a fuel vapor treatment canister provided with a concave portion (33a) that allows ventilation between a plurality of layers (14A, 14B).

According to the present invention, the space (34) between the ribs (33...
a) and an air passage (35) is formed, and the rib (33) is formed.
.. 33), the strength of the plate (22) can be kept high.
0) can be made compact, and the airflow resistance inside the canister (10) can be kept low.

[0014]

FIG. 1 is a view showing the structure of a canister for fuel vapor processing to which the present invention is applied. As shown in FIG. 1, the canister 10 of the present embodiment has a resin case 11. The case 11 has a cylindrical case main body 12 having one end opened, and a case lid 13 for closing the opening of the case main body 12. Case 11
Is filled with an adsorbent 14 such as activated carbon. Adsorbent 1
4 is a partition wall 1 extending from a ceiling wall 12a of the case body 12.
The first layer 14A and the second layer 14B are divided by 2b. In the ceiling wall 12a, an inlet pipe 15 for guiding fuel vapor to the first layer 14A, an outlet pipe 16 for discharging fuel vapor from the first layer 14A, and supply and discharge of air to and from the second layer 14B. And an open-to-atmosphere pipe 17 are provided. A cap-shaped container 18 is provided on the outer surface of the ceiling wall 12 a so as to surround the outer periphery of the introduction pipe 15. The container 18 has an inflow pipe 19 communicating therewith. The inflow pipe 19 is connected to a fuel tank of the vehicle. The fuel vapor discharged from the fuel tank is guided from the inflow pipe 19 to the inside of the container 18, where the vapor is separated into gas and liquid, and then guided from the introduction pipe 15 to the first layer 14A. The outflow pipe 16 is connected to an intake system of a vehicle engine.

On the inner surface of the ceiling wall 12a of the case body 12, a filter 20 made of non-woven fabric or the like and having air permeability is provided.
And the lower side of the filter 20 is filled with the adsorbent 14. The lower side of the adsorbent 14 is covered with a filter 21, and a resin plate 22 is further covered from below. The plate 22 is pushed up by a coil spring 23 provided between the plate 22 and the case lid 13, whereby the adsorbent 14 is packed into the case body 12 with an appropriate pressure. A communication path 24 that allows ventilation between the first layer 14A and the second layer 14B is provided between the partition wall 12b and the filter 21.

The above is the outline of the canister for processing the fuel vapor. The structure of the plate 22 according to the present invention will be further described in detail.

FIG. 2 is a plan view of the side of the plate 22 which comes into contact with the filter 21, and FIG.
FIG. 2B is a cross-sectional view along the line IIa, and FIG.
It is sectional drawing which followed the b line. As shown in these figures,
The plate 22 is provided in a lattice shape on the bottom 30, a spring receiving portion 31 receding substantially circularly in the thickness direction from the bottom 30, a peripheral wall 32 provided to surround the outer periphery of the bottom 30. And a plurality of ribs 33.

The upper end of the rib 33 is flush with the upper end of the peripheral wall 32, and the upper ends of the peripheral wall 32 and the rib 33 (FIG. 2).
(Shown by hatching) comes into contact with the filter 21 (see FIG. 1). The rib 33 has a plurality of recesses 33a.
a is provided. The recesses 33a and the spaces 34 between the ribs 33 form a fuel vapor ventilation path 35. It should be noted that the bottom portion 30 has no through-hole, so that the plate 22 has airtightness in its thickness direction (vertical direction in FIG. 1).

According to the canister constructed as described above, the fuel vapor that has passed through the first layer 14A of the adsorbent 14 is transferred to the second layer 14B via the communication path 24 between the partition wall 12b and the filter 21. Simultaneously with the inflow, the fuel vapor that has passed through the filter 21 flows into the second layer 14B via the air passage 35 on the plate 22 (see arrows in FIGS. 1 and 2). The same applies when fuel vapor is returned from the second layer 14B to the first layer 14A. Therefore, the ventilation resistance inside the canister is reduced as compared with the case where the fuel vapor moves only through the communication path 24. Since the plate 22 has no through hole and is reinforced by the rib 33, sufficient strength to hold down the adsorbent 14 can be ensured even if the thickness is reduced.

The embodiments of the present invention are not limited to those described above.
Various changes may be made. For example, the ventilation path 35 is
May be provided only in the vicinity of the communication path 24 without being provided in the entirety of the communication path. By changing the arrangement and the number of the recesses 33a, the path of the ventilation path 35 can be adjusted.
The flow can be adjusted by intensively guiding the fuel vapor to a convenient location of A, 14B, or uniformly guiding the vapor to each layer 14A, 14B. The air passage is not limited to the one formed by the concave portion on the rib and the space therebetween, and a groove-shaped air passage may be formed on the contact surface of the plate with the filter.

[0021]

As described above, according to the fuel vapor treatment canister of the present invention, the fuel vapor can move between the first layer and the second layer through the ventilation passage on the plate. The thickness of the plate can be reduced while maintaining the strength of the plate, so that the size of the canister can be reduced. In addition, the ventilation resistance inside the canister can be reduced to prevent a reduction in the processing capacity.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a canister for fuel vapor processing to which the present invention is applied.

FIG. 2 is a plan view of a plate used in the canister of FIG.

FIGS. 3A and 3B are cross-sectional views of the plate of FIG. 2, wherein FIG. 3A is a cross-sectional view taken along the line IIIa-IIIa of FIG. 2, and FIG.
Sectional drawing along IIIb-IIIb line.

FIG. 4 is a sectional view showing an example of a conventional canister.

FIG. 5 is a sectional view showing another example of a conventional canister.

[Explanation of symbols]

 Reference Signs List 1 case 1a partition wall 2 adsorbent 2A, 2B layer 3 filter 4 plate 4a through hole 5 spring 6 communication path 7 spring chamber 10 canister 11 case 12 case body 12a ceiling wall 12b partition wall 13 case lid 14 adsorbent 14A first layer 14B second layer 15 introduction pipe 16 outflow pipe 17 open-to-atmosphere pipe 18 container 19 inflow pipe 20, 21 filter 22 plate 23 coil spring 24 communication path 30 bottom part 31 spring receiving part 32 peripheral wall part 33 rib 33a recessed part 34 space 35 air passage

Claims (5)

[Claims] 1. A case body having a cylindrical shape having an open end, an adsorbent housed in the case body, and a permeable filter inserted into the case body from the one end to cover the adsorbent. A plate that is inserted into the case body so as to overlap with the filter, wherein the adsorbent is divided into a plurality of layers by a partition wall extending from the wall on the other end side of the case body toward the filter. A communication path is provided between the end of the partition wall and the filter that allows ventilation between the plurality of layers, and the plate retreats in a thickness direction of the plate from a contact surface with the filter. And a ventilation path allowing ventilation between the plurality of layers. 2. The canister for treating fuel vapor according to claim 1, wherein the plate has airtightness in a thickness direction. 3. A plurality of ribs are provided on the contact surface side of the plate to partition the contact surface side into a plurality of spaces, and the ribs are provided with a plurality of concave portions recessed in the thickness direction of the plate. 3. The canister for fuel vapor treatment according to claim 1, wherein the space between the ribs and the recess communicate with each other to form the ventilation path. 4. The canister for treating fuel vapor according to claim 1, wherein said plate is formed of a resin. 5. A cylindrical case main body having one end opened, an adsorbent housed in the case main body, and a gas-permeable filter inserted into the case main body from the one end to cover the adsorbent. A plate that is inserted into the case body so as to overlap with the filter, wherein the adsorbent is divided into a plurality of layers by a partition wall extending from the wall on the other end side of the case body toward the filter. A partition is provided between the end of the partition wall and the filter to allow ventilation between the plurality of layers, and a rib is provided on a side of the plate that contacts the filter,
A canister for fuel vapor treatment, characterized in that the ribs are provided with recesses that allow ventilation between the plurality of layers.