JPS622287Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an activated carbon container for adsorbing fuel evaporative gas, which adsorbs evaporative fuel gas generated in the fuel tank of an automobile and prevents it from escaping into the atmosphere.

[Prior art]

The partition structure below the activated carbon layer in a conventional carbon canister used as an activated carbon container for adsorbing fuel evaporative gas consists of a plate provided with a plurality of through holes and a filter adjacent to the top surface of this plate. There is.

[Problem that the invention attempts to solve]

However, in such conventional devices, the air flowing into the canister from the air inlet at the bottom of the canister enters the activated carbon layer through the through holes in the plate. The total area of is approximately 20% of the entire plate area, and dirt, dust, etc. in the atmosphere are concentratedly captured in the filter part corresponding to the position of the through hole, and when a car drives on an unpaved road. In some cases, the filter becomes extremely clogged, resulting in a problem that the function of the carbon canister is deteriorated.

The purpose of the present invention is to prevent the filter from clogging due to the concentration of atmospheric dust, etc. trapped in the filter in the through-hole portion of the plate, thereby preventing the functional deterioration of the activated carbon container for adsorbing fuel evaporative gas. It is.

[Means for solving problems]

In order to achieve this objective, according to the activated carbon container for fuel evaporative gas adsorption of the present invention, a step is provided below the activated carbon layer of the cylindrical canister body, and a primary filter and a void layer are formed on this step. An annular spacer, a plate provided with a plurality of through holes, and a secondary filter are sequentially placed thereon, and a lower surface member is provided below with an air inlet at approximately the center. In other words, the gist of the present invention is to have an activated carbon layer in the center of the cylindrical canister body, and an upper surface member having an inlet connected to the fuel evaporative gas space and an outlet connected to the purge port at the upper part. , a lower surface member having an air inlet in the lower part approximately at the center, and a stepped portion provided below the activated carbon layer;
A primary filter, an annular spacer for forming a void layer, a plate with a plurality of through holes for holding activated carbon, and a secondary filter are placed in sequence on the stepped portion, and the activated carbon is The activated carbon container for adsorbing fuel evaporative gas is characterized in that it has a filter and a plate having a plurality of through holes connected to a spring extending from the back surface of the upper surface member above.

[Effect]

Due to the presence of the void layer, the negative pressure from the outlet port is 1
The air acts uniformly over the entire top surface of the primary filter, and the air that flows into the charcoal canister from the air inlet opens in the radial direction at the bottom of the primary filter.
It passes through the primary filter uniformly over the entire surface of the primary filter and enters the void layer. Therefore, dirt, dust, etc. in the atmosphere are captured throughout the primary filter. The atmosphere purified by the primary filter enters the activated carbon layer through the through holes in the plate and the secondary filter.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

The canister 1 has a canister main body 2 and an upper surface member 3 that closes an upper opening of the canister main body.The upper surface member 3 has an inlet 4 connected to the fuel evaporative gas space of the fuel tank, The canister body 2 is provided with an outlet 5 connected to a purge port provided on the wall of the intake passage for releasing fuel evaporative gas into the intake system.
An air inlet 6 is provided approximately at the center of the lower surface member provided at the lower part of the holder. A step 9 is formed at the lower end of the cylinder of the canister body 2, and the step 9 has a primary filter 10, an annular spacer 11, and a ring spacer 11 in order from the bottom.
A plate 12 and a secondary filter 13 are mounted. The annular spacer 11 is the primary filter 10
It has a role of forming a void layer 14 of a predetermined thickness (1 mm or more) between the plate 12 and the plate 12.
A plurality of through holes 15 are provided in a uniform distribution. A predetermined amount of activated carbon 19 is packed on top of the secondary filter 13, a filter 20 is provided on the layer of activated carbon 19, and a plate 21 is further provided on top of the filter 20. The plate 21 is provided with a plurality of through holes 22 in the same proportion as the plate 12, and a spring 23 is provided between the upper surface member 3 and the plate 21 to press the plate 21 downward. In addition to purifying the air, the secondary filter 13 and the filter 20
The secondary filter 13 has the role of preventing the activated carbon 19 from falling, and the filter 20 has the role of preventing the activated carbon from scattering upward. The conduit 25 is connected to the inlet 4 and extends into the layer of activated carbon 19 to a predetermined depth.

Fuel evaporative gas generated in the fuel tank is transferred to activated carbon 1 from an inlet 4 and a conduit 25 provided on the upper surface member.
The activated carbon 19 enters the layer 9 and is adsorbed by the activated carbon 19. When negative pressure acts on the outlet 5, air is introduced from the air inlet 6 provided on the lower member, desorbs the fuel evaporative gas from the activated carbon 19, and sends it together with the desorbed fuel evaporative gas from the outlet 5 to the intake system. It will be done.

FIG. 2 shows the flow of air flowing in from the air inlet 6. Due to the presence of the void layer 14, the negative pressure from the outlet port 5 acts uniformly over the entire upper surface of the primary filter 10, so that the air flowing into the charcoal canister 1 from the air inlet 6 flows in the direction indicated by the arrow 2.
8, it spreads in the radial direction at the lower part of the primary filter 10, passes through the primary filter 10 uniformly over the entire surface of the primary filter 10, and enters the void layer 14. Therefore, dirt, dust, etc. in the atmosphere are captured throughout the primary filter 10 and are not concentrated in one part, thereby suppressing clogging of the primary filter 10.
Atmospheric air 29 purified by the primary filter 10 enters the layer of activated carbon 19 through the through hole 15 of the plate 12 and the secondary filter 13 as indicated by an arrow 30. Therefore, since the air passing through the secondary filter 13 has been purified in advance in the primary filter 10, there is almost no clogging of the secondary filter 13.

[Effect of idea]

As described above, according to the present invention, a stepped portion is provided below the activated carbon layer of the canister body, and a primary filter and a secondary filter are provided on this stepped portion via a predetermined gap layer formed by an annular spacer. is,
Moreover, since the air inlet is provided almost at the center of the bottom member, air from the atmosphere passes through the entire primary filter uniformly, preventing clogging of the primary filter itself, and preventing the secondary filter from clogging. The life of the filter can also be dramatically extended, and deterioration in the functionality of the activated carbon container can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a diagram showing the flow of air from an air inlet. 1...Charcoal canister, 6...Air inlet, 10...Primary filter, 12...Plate,
13...Secondary filter, 14...Void layer, 15...
...Through hole, 19...Activated carbon.

Claims (1)

[Claims for Utility Model Registration] A cylindrical canister body that has an activated carbon layer in the center, and has an upper surface member that has an inlet connected to the fuel evaporative gas space and an outlet connected to the purge port. and has a lower surface member with an air inlet at approximately the center thereof, and a stepped portion is provided below the activated carbon layer,
A primary filter, an annular spacer for forming a void layer, a plate with a plurality of through holes for holding activated carbon, and a secondary filter are sequentially placed on the step, and the activated carbon layer An activated carbon container for adsorbing fuel evaporative gas, characterized in that it has a filter and a plate having a plurality of through holes connected to a spring extending from the back surface of the upper surface member above the upper surface member.