JP2018204438A - Evaporated fuel treatment device - Google Patents

Abstract

To provide an evaporated fuel treatment device capable of suppressing an increase in the ventilation resistance.SOLUTION: A sub canister 31 includes a sub case 32, a first filter 38, a second filter 39 and a third filter 40 partitioning the sub case 32 into three or more adsorption chambers 41-44 continuously arranged in series, and having gas permeability, and at least two or more types of first adsorbents 51 and second adsorbents 52 individually filled in the adsorption chambers 41-44, and different in average grain size. In the first absorption chamber 41 located on the end side of the sub case 32, the first adsorbents 51 are filled having the smallest average grain size.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fuel vapor processing apparatus.

  Some evaporative fuel processing apparatuses mainly used for vehicles such as automobiles adsorb evaporative fuel (vapor) evaporated from a fuel tank and purge the fuel when the engine is operating (see, for example, Patent Document 1). ). The evaporative fuel processing apparatus includes a case, a partitioning member such as a filter having air permeability that partitions the inside of the case into a plurality of adsorption chambers, and an adsorbent such as granular activated carbon that is filled in the adsorption chamber and adsorbs and desorbs the evaporated fuel And.

JP 2007-270726 A

  In the evaporative fuel processing apparatus, for example, at least two types of adsorbents having different average particle sizes may be filled in three or more adsorbing chambers arranged in series. In this case, depending on the arrangement of the adsorbent, the ventilation resistance is increased. For example, an adsorbent having the smallest average particle diameter is filled in an intermediate adsorption chamber among three adsorbing chambers arranged in series, and adsorbents having the largest average particle diameter are filled in the adsorption chambers on both sides. In this case, since the partition members having openings that suppress the outflow of the adsorbent having the smallest average particle diameter must be arranged in two places between the intermediate adsorption chamber and the adsorption chambers on both sides, the ventilation resistance is Increase.

  The problem to be solved by the present invention is to provide an evaporative fuel processing apparatus capable of suppressing an increase in ventilation resistance.

  The above-described problem can be solved by the evaporated fuel processing apparatus of the present invention.

  According to a first aspect of the present invention, there is provided a case, a partition member having air permeability for partitioning the inside of the case into three or more adsorption chambers continuously arranged in series, and at least 2 filled with each adsorption chamber and having different average particle diameters An evaporative fuel processing apparatus comprising at least one type of adsorbent, wherein the adsorbent chamber located on the end side of the case is filled with an adsorbent having the smallest average particle diameter. is there.

  According to the first invention, the partition member having an opening that suppresses the outflow of the adsorbent having the smallest average particle diameter is provided between the adsorption chamber located on one end side of the case and the adsorption chamber adjacent to the adsorption chamber. What is necessary is just to arrange | position in one place. Therefore, an increase in ventilation resistance can be suppressed by reducing the number of used partition members having small openings.

  According to a second aspect of the present invention, there is provided a case, an air-permeable partition member that partitions the interior of the case into three or more adsorption chambers that are continuously arranged in series, and at least 2 that is filled in each adsorption chamber and has a different average particle diameter. An evaporative fuel processing apparatus comprising at least two types of adsorbents, wherein one of the two adsorbing chambers adjacent to each other is filled with an adsorbent having the largest average particle diameter. The other one of the two adsorbing chambers is an evaporative fuel processing apparatus filled with an adsorbent having the largest average particle diameter or an adsorbent having the second largest average particle diameter.

  According to the second invention, the partition member having an opening that suppresses the outflow of the adsorbent having the largest average particle diameter or the adsorbent having the second largest average particle diameter may be disposed between the adsorbing chambers adjacent to each other. . Therefore, an increase in ventilation resistance can be suppressed by increasing the opening of the partition member between two adjacent adsorption chambers.

  According to a third invention, in the first or second invention, in the case, the first flow path portion and the second flow path portion extending in the vertical direction and the lower end portions of both flow path portions are communicated with each other. A U-shaped flow path having a communication portion is formed, an upper end portion of the case has an atmosphere side port communicating the first flow path portion to the atmosphere side, and an evaporated fuel in the second flow path portion. And a purge port for purging the evaporated fuel from the second flow path section, and the first flow path section has three or more adsorption chambers arranged in series in succession. It is an evaporative fuel processing apparatus which is arrange | positioned and is provided with the fine powder reservoir part which accumulates the fine powder of the said adsorbent in the airflow stagnation part which the stagnation of an air flow produces in the said communication part.

  According to the third aspect of the present invention, the fine powder of the adsorbent in each flow path part falls through each flow path part and accumulates in the fine powder reservoir provided in the airflow stagnation part of the communication part. For this reason, it can suppress that a fine powder moves to the other channel part by the airflow which flows through a U-shaped channel.

  According to a fourth invention, in the first or second invention, in the case, a first flow path portion and a second flow path portion extending in a horizontal direction and one end portions of both flow path portions are communicated with each other. A U-shaped flow path having a communication portion is formed, and an end on the opposite side of the communication path of the case is connected to the atmosphere side port for communicating the first flow path portion to the atmosphere side; A tank port for introducing evaporated fuel into the two flow path portions and a purge port for purging the evaporated fuel from the second flow path portion are provided, and the first flow path portions are continuously arranged in series. Three or more adsorption chambers are arranged, and the bottom surface of the U-shaped flow path is formed as an inclined surface inclined obliquely downward from the atmosphere side port side toward the communication portion side, The airflow stagnation part where airflow stagnation occurs in the communication part is provided with a fine powder reservoir for storing fine particles of the adsorbent. It is a fuel vapor processing apparatus.

  According to 4th invention, the fine powder of the adsorbent in each flow path part flows down on the bottom face of a U-shaped flow path, and accumulates in the fine powder reservoir part provided in the airflow stagnation part of the communication part. For this reason, it can suppress that a fine powder moves to the other channel part by the airflow which flows through a U-shaped channel.

  According to the fuel vapor processing apparatus of the present invention, an increase in ventilation resistance can be suppressed.

It is the schematic which shows a canister apparatus. 1 is a cross-sectional view showing a sub-canister according to Embodiment 1. FIG. FIG. 5 is a cross-sectional view showing a sub-canister according to a second embodiment. FIG. 6 is a front sectional view showing a main canister according to a third embodiment. FIG. 6 is a plan sectional view showing a main canister according to a fourth embodiment. It is a sectional side view which shows a main canister.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[Outline of canister equipment]
Prior to the description of the embodiment, an outline of a canister device that is an object of the embodiment will be described. FIG. 1 is a schematic view showing a canister device. The canister device is installed in a vehicle such as an automobile equipped with an engine as an internal combustion engine.

  As shown in FIG. 1, the canister device 10 includes a main canister 12 and a sub-canister 14. The main canister 12 includes a main case 16 having a U-shaped flow path, a flow path having a so-called U-shaped flow structure. A main side connection port 17 that communicates with the atmosphere side, a tank port 18 that introduces evaporated fuel, and a purge port 19 that purges evaporated fuel are formed on one end side (right end side in FIG. 1) of the main case 16. Yes.

  The main side connection port 17 communicates with one end of a U-shaped flow path in the main case 16. The tank port 18 and the purge port 19 are communicated with the other end of the U-shaped flow path in the main case 16. A U-shaped channel in the main case 16 is filled with a granular adsorbent (not shown) capable of adsorbing and desorbing evaporated fuel. The tank port 18 communicates with the fuel tank 21. The purge port 19 is connected to the intake passage of the engine 23 via the purge valve 22. The purge valve 22 is controlled to open and close by an electronic control unit (ECU) 24.

  The sub canister 14 includes a sub case 26 having a straight flow path. A sub-side connection port 27 is formed on one end side (right end side in FIG. 1) of the sub case 26. At the other end side (left end side in FIG. 1) of the sub case 26, an atmospheric port 28 that is open to the atmosphere is formed. The sub-side connection port 27 communicates with one end of the flow path in the sub case 26. The atmospheric port 28 communicates with the other end of the flow path in the sub case 26. The flow path in the sub case 26 is filled with a granular adsorbent (not shown) that can adsorb and desorb the evaporated fuel. The main side connection port 17 and the sub side connection port 27 are connected via a connection pipe 29.

[Operation of canister device 10]
In the canister device 10, the evaporated fuel introduced from the tank port 18 into the main canister 12 is adsorbed by both canisters 12 and 14 (specifically, an adsorbent). Further, when the purge valve 22 is opened under the control of the electronic control unit (ECU) 24 during the operation of the engine 23, the air sucked into the sub-canister 14 from the atmospheric port 28 by the intake negative pressure is The gas is purged from the purge port 19 to the intake passage of the engine 23 through the canisters 12 and 14 (specifically, a flow path). At that time, the evaporated fuel is desorbed from both the canisters 12 and 14 (specifically, the adsorbent).

[Embodiment 1]
FIG. 2 is a sectional view showing the sub-canister. As shown in FIG. 2, the sub-canister (denoted by reference numeral 31) of this embodiment is used in place of the sub-canister 14 of the canister device 10 (see FIG. 1).

[Configuration of sub-canister 31]
The sub case 32 of the sub canister 31 has a sub-side connection port 33 and an atmospheric port 34. A first filter 38, a second filter 39, and a third filter 40 are disposed in the flow path 36 in the sub case 32 at a predetermined interval from each other. These filters 38, 39, and 40 are formed in a sheet shape, and partition the flow path 36 in the subcase 32 into four chambers 41 to 44 that are continuously arranged in series. Note that the first adsorption chamber 41, the second adsorption chamber 42, the third adsorption chamber 43, and the fourth adsorption chamber 44 are referred to from the sub-side connection port 33 side toward the atmosphere port 34 side.

  A perforated plate 46 is disposed at one end (the right end in FIG. 2) in the sub case 32. The porous plate 46 partitions the sub-side connection port 33 and the first adsorption chamber 41. On the side of the first adsorption chamber 41 of the porous plate 46, a sheet-like fourth filter 47 is arranged in a laminated form. The perforated plate 46 is biased by a spring member 48 in a direction away from the sub-side connection port 33 (left side in FIG. 2). Thereby, the scuffing of the adsorbents 51 and 52 described later is suppressed. Further, a sheet-like fifth filter 49 is disposed at the other end (the left end in FIG. 2) in the sub case 32. The fifth filter 49 partitions the atmosphere port 34 and the fourth adsorption chamber 44.

  For the sub-canister 31, two types of adsorbents 51 and 52 having different average particle diameters are used. Of the two types of adsorbents 51 and 52 having different average particle diameters, the adsorbent having a small average particle diameter (referred to as “first adsorbent”) 51 is placed in the first adsorbing chamber 41 located on one end side of the sub case 32. Filled. In addition, an adsorbent 52 (referred to as “second adsorbent”) 52 having a large average particle size is filled in the second adsorption chamber 42, the third adsorption chamber 43, and the fourth adsorption chamber 44.

  For the first adsorbent 51, for example, an adsorbent having an average particle diameter of 2 mm is used. As the second adsorbent 52, for example, an adsorbent having an average particle diameter of 5 mm is used. For the first adsorbent 51 and the second adsorbent 52, for example, granular activated carbon, crushed activated carbon (crushed charcoal), granulated charcoal obtained by granulating granular or powdered activated carbon together with a binder, or the like is used. it can. In the present embodiment, as the first adsorbent 51, substantially cylindrical granulated coal is used.

  For the first filter 38, a foamed urethane sheet having an opening that suppresses the outflow of the first adsorbent 51 is used. The opening of the first filter 38 is, for example, 30 ± 4 cells / 25 mm. For the second filter 39 and the third filter 40, a foamed urethane sheet having an opening that suppresses the outflow of the second adsorbent 52 is used. The opening of the second filter 39 and the third filter 40 is, for example, 15 ± 4 cells / 25 mm. For the fourth filter 47 and the fifth filter 49, a nonwoven fabric having an opening that suppresses the outflow of the first adsorbent 51 is used. The opening of the fourth filter 47 and the fifth filter 49 is, for example, 30 ± 4 cells / 25 mm. Each porous plate 46 is a porous plate having coarser mesh than the fourth filter 47 and the fifth filter 49. The aperture of the porous plate 46 is, for example, 30 or more cells / 25 mm.

  The sub-canister 31 corresponds to an “evaporated fuel processing device” in the present specification. The subcase 32 corresponds to a “case” in the present specification. The first filter 38, the second filter 39, and the third filter 40 correspond to a “partition member” in this specification. The first adsorbent 51 corresponds to the “adsorbent with the smallest average particle diameter” as used in this specification. The second adsorbent 52 corresponds to the “adsorbent having the largest average particle diameter” in the present specification.

[Operation and effect of sub-canister 31]
According to the sub-canister 31 described above, the first adsorption chamber 41 positioned on one end side of the sub-case 32 and the first filter 38 having an opening that suppresses the outflow of the first adsorbent 51 having the smallest average particle diameter are provided. What is necessary is just to arrange | position in one place between the 2nd adsorption chambers 42 adjacent to the 1st adsorption chamber 41. FIG. Therefore, an increase in ventilation resistance can be suppressed by reducing the number of used first filters 38 having a small mesh size.

  For example, it is assumed that the first adsorption material 51 is filled in the second adsorption chamber 42 and the second adsorption material 52 is filled in the first adsorption chamber 41 and the third adsorption chamber 43. In this case, an opening that suppresses the outflow of the first adsorbent 51 is provided between the first adsorption chamber 41 and the second adsorption chamber 42 and between the second adsorption chamber 42 and the third adsorption chamber 43. The first filter 38 having it must be arranged. That is, since the number of the first filters 38 having a small mesh opening is two, the ventilation resistance is increased. On the other hand, according to the present embodiment, since the number of the first filters 38 having a small mesh opening is one, an increase in ventilation resistance can be suppressed.

  The adjacent second adsorption chamber 42 and third adsorption chamber 43 are filled with the second adsorbent 52 having the largest average particle diameter. For this reason, the second filter 39 having an opening that suppresses the outflow of the second adsorbent 52 having the largest average particle diameter may be disposed between the second adsorption chamber 42 and the third adsorption chamber 43. Therefore, by increasing the opening of the second filter 39 between the second adsorption chamber 42 and the third adsorption chamber 43 as compared with the opening of the first filter 38, an increase in ventilation resistance can be suppressed. .

  Further, the adjacent third adsorption chamber 43 and fourth adsorption chamber 44 are filled with the second adsorbent 52 having the largest average particle diameter. For this reason, the third filter 40 having openings that suppress the outflow of the second adsorbent 52 having the largest average particle diameter may be disposed between the third adsorption chamber 43 and the fourth adsorption chamber 44. Therefore, by increasing the opening of the third filter 40 between the third adsorption chamber 43 and the fourth adsorption chamber 44 as compared with the opening of the first filter 38, an increase in ventilation resistance can be suppressed. .

  For example, it is assumed that one of the adjacent second adsorption chamber 42 and the third adsorption chamber 43 is filled with the second adsorbent 52 and the other is filled with the first adsorbent 51. In this case, since the first filter 38 having an opening that suppresses the outflow of the first adsorbent 51 must be disposed between the second adsorption chamber 42 and the third adsorption chamber 43, the ventilation resistance increases. On the other hand, according to the present embodiment, the second filter 39 having a large opening is disposed between the second adsorption chamber 42 and the third adsorption chamber 43, and the third adsorption chamber 43 and the fourth adsorption chamber 43 are arranged. What is necessary is just to arrange | position the 3rd filter 40 of a large opening between the chambers 44. FIG. Therefore, an increase in ventilation resistance can be suppressed by making the openings of the second filter 39 and the third filter 40 larger than the openings of the first filter 38.

  In the present embodiment, the second adsorption chamber 42, the third adsorption chamber 43, and the fourth adsorption chamber 44 are filled with the second adsorbent 52. However, at least one adsorption chamber among these adsorption chambers 42 to 44 is used. For this, an adsorbent having an average particle size larger than that of the first adsorbent 51 and different from that of the second adsorbent 52 may be used. Further, the first adsorbent 51 may be disposed in the fourth adsorption chamber 44 located on the other end side of the sub case 32.

[Embodiment 2]
FIG. 3 is a sectional view showing the sub-canister. As shown in FIG. 3, the present embodiment is a modification of the adsorbent filled in the second adsorption chamber 42 of the sub-canister 31 of the first embodiment (see FIG. 2). A duplicate description will be omitted. The second adsorbing chamber 42 is filled with an adsorbing material 53 (referred to as “third adsorbing material”) 53 having the next largest average particle diameter after the second adsorbing material 52. The third adsorbent 53 has a larger average particle diameter than the first adsorbent 51. For the third adsorbent 53, for example, an adsorbent having an average particle diameter of 4 mm is used. The third adsorbent 53 may be, for example, granular activated carbon, crushed activated carbon (crushed charcoal), granulated charcoal obtained by granulating granular or powdered activated carbon together with a binder, and the like. The third adsorbent 53 corresponds to the “second adsorbent with the largest average particle diameter” in this specification.

  A foamed urethane sheet having an aperture that suppresses the outflow of the third adsorbent 53 is used for the second filter (reference numeral 39A) of the present embodiment. The mesh size of the second filter 39A is, for example, 18 ± 4 cells / 25 mm.

  According to the present embodiment, the second filter 39 </ b> A having an opening that suppresses the outflow of the third adsorbent 53 having the second largest average particle diameter is disposed between the second adsorption chamber 42 and the third adsorption chamber 43. do it. Therefore, by increasing the opening of the second filter 39A between the third adsorption chamber 43 and the fourth adsorption chamber 44 as compared with the opening of the first filter 38, an increase in ventilation resistance can be suppressed. . Therefore, by increasing the opening of the second filter 39A between the third adsorption chamber 43 and the fourth adsorption chamber 44, an increase in ventilation resistance can be suppressed.

  In the present embodiment, the second adsorption chamber 42 is filled with the third adsorbent 53 and the third adsorption chamber 43 is filled with the second adsorbent 52. However, the second adsorbent 53 is filled with the second adsorbent 53. The third adsorbing chamber 43 may be filled with the third adsorbent 53. One of the two adjacent adsorbing chambers is filled with an adsorbent having the largest average particle size, and the other adsorbing chamber of the two adsorbing chambers has the largest average particle size. The adsorbent having a large average particle diameter or the adsorbent having the second largest average particle diameter may be filled, and the other adsorption chambers may be filled with an adsorbent having an arbitrary average particle diameter. For example, the first adsorption chamber 41 may be filled with an adsorbent having an average particle size larger than that of the first adsorbent and smaller than that of the second adsorbent 52. Further, the fourth adsorbing chamber 44 may be filled with the first adsorbent 51 or may be filled with an adsorbent having an average particle size smaller than that of the second adsorbent 52 or the third adsorbent 53.

[Embodiment 3]
FIG. 4 is a cross-sectional view showing the main canister. As shown in FIG. 4, the main canister (reference numeral 55) is used in place of the main canister 12 of the canister device 10 (see FIG. 1).

[Configuration of main canister 55]
As shown in FIG. 4, the main case 56 of the main canister 55 has a main side connection port 57, a tank port 58, and a purge port 59. Further, since the main canister 55 is used alone, the main side connection port 57 is an atmospheric port 57 (the same reference numeral is attached). The atmospheric port 57 corresponds to an “atmospheric side port” in this specification.

  The main canister 55 is mounted on the vehicle with the atmospheric port 57, the tank port 58, and the purge port 59 facing upward (upward in FIG. 4). A partition wall 61 is provided in the main case 56 so as to form a U-shaped flow path 63 in the main case 56. The U-shaped flow path 63 communicates the first flow path section 63a on one side (right side in FIG. 4), the second flow path section 63b on the other side (left side in FIG. 4), and both flow path sections 63a and 63b. And a communicating portion 63c. The upper end portion of the first flow path portion 63a communicates with the atmospheric port 57. The tank port 58 and the purge port 59 communicate with the upper end portion of the second flow path portion 63b. The upper end portion of the second flow path portion 63 b is partitioned by the partition wall 64 into a portion communicating with the tank port 58 and a portion communicating with the purge port 59.

  The inside of the 1st flow path part 63a is comprised similarly to the inside of the flow path 36 of the subcanister 31 (refer FIG. 2) of Embodiment 1. FIG. For this reason, the description is abbreviate | omitted by attaching | subjecting the same code | symbol to the same site | part. Further, the air port side of the sub canister 31 corresponds to the air port 57 side of the main canister 55, and the sub-side connection port 33 side of the sub-canister 31 also corresponds to the communication part 63c side.

  The inside of the second flow path portion 63b is a fifth adsorption chamber 65. A sheet-like sixth filter 67 is disposed on the left and right sides of the partition wall 64 at the upper end of the second flow path portion 63b. The sixth filter 67 on the left side partitions the tank port 58 and the fifth adsorption chamber 65. The sixth filter 67 on the right side partitions the purge port 59 and the fifth adsorption chamber 65. A perforated plate 69 is disposed at the lower end of the second flow path portion 63b. The perforated plate 69 partitions the communication portion 63 c and the fifth adsorption chamber 65. On the side of the fifth adsorption chamber 65 of the perforated plate 69, a sheet-like seventh filter 70 is arranged in a laminated form. The fifth adsorption chamber 65 is filled with the first adsorbent 51. The perforated plate 69 is urged by the spring member 72 in a direction away from the communication portion 63c side. Thereby, the roughness of the 1st adsorption material 51 of the 5th adsorption chamber 65 is controlled.

  For the sixth filter 67 and the seventh filter 70, a nonwoven fabric having an opening similar to that of the fourth filter 47 and the fifth filter 49 is used. Further, a porous plate having the same opening as the porous plate 46 is used as the porous plate 69. The main canister 55 corresponds to an “evaporated fuel processing device” in the present specification. The main case 56 corresponds to a “case” in this specification.

  The bottom part of the communication part 63c is a part where the stagnation of the air flow occurs (the part where stagnation is likely to occur). A protruding wall 76 having a predetermined height is formed on the bottom surface of the communication portion 63c to partition the bottom portion left and right. The protruding wall 76 is formed to face the lower end surface of the partition wall 61 with a predetermined interval. Due to the protruding wall 76, left and right fine powder reservoirs 78 having a groove shape are formed in the airflow stagnation part 74. Note that the fine powder P is generated by pulverization of each of the adsorbents 51 and 52 due to vibration accompanying traveling of the vehicle.

[Operation and effect of main canister 55]
According to the main canister 55 described above, the configuration in the first flow path portion 63a is the same as the configuration in the flow path 36 (see FIG. 2) of the sub-canister 31 of the first embodiment. Thereby, the effect | action and effect similar to Embodiment 1 can be acquired.

  Further, the fine powder P of the first adsorbent 51 and the second adsorbent 52 in the first flow path portion 63a of the U-shaped flow path 63 falls through the flow path portion 63a, and the airflow stagnation portion 74 of the communication portion 63c. Is accumulated in the fine powder reservoir 78 on the right side. Further, the fine powder P of the first adsorbent 51 in the second flow path portion 63b of the U-shaped flow path 63 falls through the second flow path portion 63b, and the fine powder on the left side of the airflow stagnation portion 74 of the communication portion 63c. It collects in the reservoir part 78. For this reason, it can suppress that the fine powder P moves to the other channel part by the airflow which flows through the U-shaped channel 63. As a result, it can suppress that the adsorbent 51 or 52 of each adsorption chamber 41-44,65 mixes with the adsorbent 52 or 51 from which adsorption | suction performance differs.

  Further, the sub-canister 14 (see FIG. 1) may be connected to the main canister 55. In this case, the atmospheric port 57 becomes the main side connection port 57.

[Embodiment 4]
FIG. 5 is a plan sectional view showing the main canister, and FIG. 6 is a side sectional view. As shown in FIG. 5, this embodiment is a modification of the main canister 55 of the third embodiment (see FIG. 4). In the main canister 55 of the present embodiment, the protruding wall 76 and the fine powder reservoir 78 in the main canister 55 (see FIG. 4) are omitted. In addition, the main canister 55 has a tank port 58, a purge port 59, and an atmospheric port 57 side in the horizontal direction (for example, the front side) so that the U-shaped flow path 63 is U-shaped in a plan view with respect to the vehicle. ) (See FIG. 6).

  As shown in FIG. 6, the upper wall portion (reference numeral 56a) of the main case 56 is disposed horizontally. Further, the lower wall portion (reference numeral 56b) of the main case 56 is inclined so as to incline downward from the atmosphere port 57 side (left side in FIG. 6) toward the communication portion 63c side (right side in FIG. 6). Is formed. That is, the bottom surface of the U-shaped channel 63 (the upper surface of the lower wall portion 56b) is formed as an inclined surface that is inclined obliquely downward from the atmosphere port 57 side toward the communication portion 63c side.

  A concave portion 81 having a U-shaped cross section extending in the left-right direction is formed on the airflow stagnation portion 80 where the stagnation of the air flow occurs in the communication portion 63c, that is, the bottom surface of the communication portion 63c (the rear end portion of the lower wall portion 56b). . A groove-shaped fine powder reservoir portion 82 is formed by the concave portion 81 (see FIG. 5).

  According to the present embodiment, the fine powder P of the first adsorbent 51 and the second adsorbent 52 in each flow path portion 63a, 63b flows down the bottom surface of the U-shaped flow path 63 (the upper surface of the lower wall portion 56b). Then, it accumulates in the fine powder reservoir 82 provided in the airflow stagnation part 80 of the communication part 63c. For this reason, it can suppress that the fine powder P moves to the other channel part by the airflow which flows through the U-shaped channel 63. As a result, it can suppress that the adsorbent 51 or 52 of each adsorption chamber 41-44,65 mixes with the adsorbent 52 or 51 from which adsorption | suction performance differs.

[Other Embodiments]
The present invention is not limited to the above-described embodiments, and modifications can be made without departing from the present invention. For example, the number and shape of the suction chambers of the main canister 55 and / or the sub canister 31 may be changed as appropriate. The materials of the filters 38, 39, 39A, 40, 47, 49, 67, 70 may be changed as appropriate. Further, the spring members 48 and 72 may be changed to elastic members such as rubber or may be omitted.

31 Sub-canister (evaporative fuel treatment device)
32 Subcase (case)
33 Sub-side connection port 34 Atmospheric port 38 First filter (partition member)
39 Second filter (partition member)
39A Second filter (partition member)
40 Third filter (partition member)
41 1st adsorption chamber 42 2nd adsorption chamber 43 3rd adsorption chamber 44 4th adsorption chamber 51 1st adsorbent (adsorbent with the smallest average particle diameter)
52 Second adsorbent (adsorbent with the largest average particle size)
53 Third adsorbent (second adsorbent with the largest average particle size)
55 Main canister (evaporated fuel processing equipment)
56 Main Case (Case)
57 Atmosphere port (Atmosphere side port)
58 tank port 59 purge port 63 U-shaped flow path 63a first flow path part 63b second flow path part 63c communication part 74 airflow stagnation part 78 fine powder reservoir part 80 airflow stagnation part 82 fine powder reservoir part P fine powder

Claims (4)

Case and
An air-permeable partition member that partitions the interior of the case into three or more adsorbing chambers arranged continuously in series;
At least two kinds of adsorbents filled in each adsorption chamber and having different average particle diameters;
An evaporative fuel processing apparatus comprising:
The evaporative fuel processing apparatus, wherein the adsorption chamber located on the end side of the case is filled with an adsorbent having the smallest average particle diameter. Case and
An air-permeable partition member that partitions the interior of the case into three or more adsorbing chambers arranged continuously in series;
At least two kinds of adsorbents filled in each adsorption chamber and having different average particle diameters;
An evaporative fuel processing apparatus comprising:
One of the two adjacent adsorbing chambers is filled with an adsorbent having the largest average particle diameter,
The evaporative fuel processing apparatus, wherein the other adsorption chamber of the two adsorption chambers is filled with an adsorbent having the largest average particle diameter or an adsorbent having the second largest average particle diameter. The evaporative fuel processing apparatus according to claim 1 or 2,
A U-shaped channel having a first channel portion and a second channel portion extending in the vertical direction and a communication portion that communicates the lower end portions of both channel portions with each other is formed in the case. And
The upper end of the case has an atmosphere side port communicating the first flow path portion to the atmosphere side, a tank port for introducing evaporated fuel to the second flow path portion, and evaporative fuel from the second flow path portion. There is a purge port to purge,
In the first flow path portion, three or more adsorption chambers arranged in series are arranged,
An evaporative fuel processing apparatus, wherein an airflow stagnation part where airflow stagnation occurs in the communication part is provided with a fine powder reservoir for accumulating fine powder of the adsorbent. The evaporative fuel processing apparatus according to claim 1 or 2,
A U-shaped flow path having a first flow path section and a second flow path section extending in the horizontal direction and a communication section that communicates one end portions of both flow path sections is formed in the case. And
At the end of the case opposite to the communication path, an atmosphere side port that communicates the first flow path portion to the atmosphere side, a tank port that introduces evaporated fuel to the second flow path portion, and a second A purge port for purging the evaporated fuel from the flow path is provided,
In the first flow path portion, three or more adsorption chambers arranged in series are arranged,
The bottom surface of the U-shaped channel is formed in an inclined surface that is inclined obliquely downward from the atmosphere side port side toward the communication portion side,
An evaporative fuel processing apparatus, wherein an airflow stagnation part where airflow stagnation occurs in the communication part is provided with a fine powder reservoir for accumulating fine powder of the adsorbent.

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