Patent Publication Number: US-2023149846-A1

Title: Canister

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority based on Japanese patent application No. 2021-185057 filed on Nov. 12, 2021 with the Japan Patent Office and the entire disclosure of which is incorporated hereinby reference. 
     BACKGROUND 
     The present disclosure relates to a canister. 
     A canister, which inhibits the discharge of evaporated fuel to the atmosphere, is attached to a fuel tank of a vehicle. The canister adsorbs the evaporated fuel to an adsorbent, desorbs fuel from the adsorbent with taken-in air for purging, and supplies the purged fuel to an engine. 
     Generally, the canister at least includes a main chamber to which a charge port is connected, and a sub chamber connected to the main chamber. Each of the main chamber and the sub chamber contains an adsorbent. In such a canister, when a large amount of evaporated fuel is supplied from the charge port, the evaporated fuel that was not adsorbed in the main chamber and the sub chamber may be discharged from the atmosphere port. 
     Thus, a canister provided with a blow-by prevention part is known to inhibit the discharge of the evaporated fuel from the sub chamber to the atmosphere (see Japanese Unexamined Patent Application Publication No. 2012-36734). 
     SUMMARY 
     In the above-described canister, the blow-by prevention part is arranged adjacent to the atmosphere port. Thus, the evaporated fuel might be discharged to the atmosphere. 
     In one aspect of the present disclosure, it is preferable to provide a canister that can inhibit discharge of evaporated fuel to the atmosphere. 
     One aspect of the present disclosure is a canister for absorbing and desorbing evaporated fuel occurred in a fuel tank of a vehicle. The canister includes a charge port that takes in evaporated fuel, a purge port that discharges the evaporated fuel, an atmosphere port open to the atmosphere, a main chamber to which the charge port and the purge port are connected, a sub chamber to which the atmosphere port is connected directly or through another chamber, an intermediate chamber arranged between the main chamber and the sub chamber in a flow path of the evaporated fuel, the intermediate chamber being connected to each of the main chamber and the sub chamber, a first adsorbent stored in the main chamber, a second adsorbent stored in the sub chamber, and a third adsorbent stored in the intermediate chamber. An adsorption capacity of the third adsorbent as a whole is smaller than each of an adsorption capacity of the first adsorbent as a whole and an adsorption capacity of the second adsorbent as a whole. 
     With this configuration, it is possible to delay the moving of the evaporated fuel, which was not adsorbed in the main chamber, to the sub chamber. Thus, it is possible to reduce the discharge of the evaporated fuel to the atmosphere. The adsorption capacity of the third adsorbent as a whole in the intermediate chamber is made smaller than the adsorption capacity of the first adsorbent as a whole and the adsorption capacity of the second adsorbent as a whole, and thus, the intermediate chamber can be made compact. As a result, it is possible to inhibit the upsizing of the canister while reducing the discharge of the evaporated fuel to the atmosphere. 
     In one aspect of the present disclosure, in the intermediate chamber, a ratio (L/D) of a length L [mm] in a gas flow direction to an equivalent diameter D [mm] in a cross section perpendicular to the gas flow direction may be equal to or less than 1. With this configuration, a ventilation resistance of the intermediate chamber can be reduced. In addition, the length of the intermediate chamber can be reduced, which promotes the effect of inhibiting the upsizing of the canister. 
     In one aspect of the present disclosure, the equivalent diameter in the cross section perpendicular to the gas flow direction in the intermediate chamber may be equal to or less than an equivalent diameter in a cross section perpendicular to a gas flow direction in the sub chamber and less than an equivalent diameter in a cross section perpendicular to a gas flow direction in the main chamber. With this configuration, desorption properties of the third adsorbent in the intermediate chamber can be enhanced. As a result, an adsorption effect of the intermediate chamber at the time of re-absorption of the evaporated fuel increases, which promotes the effect of reducing the discharge of the evaporated fuel to the atmosphere. 
     One aspect of the present disclosure may further include a flow path forming member connected to an end of the main chamber on a side opposite the charge port of the main chamber, and a spring that presses the flow path forming member toward the main chamber. The intermediate chamber may be arranged inside the flow path forming member. With this configuration, the intermediate chamber can be formed by utilizing a part of the structure of the flow path. Thus, it is possible to promote the effect of inhibiting the upsizing of the canister. 
     One aspect of the present disclosure may further include a communicating passage that connects the main chamber and the sub chamber to communicate with each other. The intermediate chamber may be arranged in the communicating passage. With this configuration, the intermediate chamber can be formed by utilizing a part of the communicating passage. Thus, it is possible to promote the effect of inhibiting the upsizing of the canister. 
     In one aspect of the present disclosure, the communicating passage may have a crank portion that bends a gas flow direction. The intermediate chamber may be arranged in the crank portion. With this configuration, the main chamber and the sub chamber can have structures similar to conventional structures. 
     In one aspect of the present disclosure, the communicating passage may have a linear part aligned linearly with the sub chamber. The intermediate chamber may be arranged in the linear part. This configuration makes it easy to arrange the intermediate chamber and to hold the third adsorbent. 
     It should be noted that the “equivalent diameter in the cross section perpendicular to the gas flow direction” means a value obtained by calculating a diameter (D=(S/π) 1/2 ×2) of a perfect circle having an area S that is the same as a cross-sectional area perpendicular to the gas flow direction in each chamber, and by averaging the diameters along the gas flow direction in each chamber. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present disclosure will be described hereinafter by way of example with reference to the accompanying drawings, in which: 
         FIG.  1    is a schematic sectional view of a canister in an embodiment; 
         FIG.  2 A  is a schematic perspective view of a flow path component in the canister of  FIG.  1   , and  FIG.  2 B  is a schematic sectional view taken along line IIB-IIB of  FIG.  2 A ; 
         FIG.  3 A  is a schematic sectional view taken along line IIIA-IIIA of  FIG.  1   , and  FIG.  3 B  is a schematic sectional view taken along line IIIB-IIIB of  FIG.  1   ; 
         FIG.  4    is a schematic sectional view of a canister in an embodiment different from  FIG.  1   ; 
         FIG.  5    is a schematic sectional view of a canister in another embodiment different from  FIG.  1   ; and 
         FIG.  6    is a schematic perspective view of a partition grid in the canister of  FIG.  5   . 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     1. First Embodiment 
     [1-1. Configuration] 
     A canister  1  shown in  FIG.  1 A  adsorbs and desorbs evaporated fuel occurred in a fuel tank of a vehicle. 
     The canister  1  includes a charge port  2 A, a purge port  2 B, an atmosphere port  2 C, a main chamber  3 , a sub chamber  4 , an intermediate chamber  5 , a communicating passage  6 , a first adsorbent  7 , a second adsorbent  8 , and a third adsorbent  9 . 
     &lt;Port&gt; 
     The charge port  2 A is connected to the fuel tank of the vehicle via piping, The charge port  2 A is configured to take the evaporated fuel generated in the fuel tank into the canister  1 . 
     The purge port  2 B is connected to an intake pipe of an engine of the vehicle via a purge valve. The purge port  2 B is configured to discharge the evaporated fuel from the canister  1  and supply it to the engine. 
     The atmosphere port  2 C is connected to a filling port of the vehicle via piping, and is open to the atmosphere. The atmosphere port  2 C discharges gas from which the evaporated fuel has been removed to the atmosphere. The atmosphere port  2 C also takes in external air (i.e. purge air) to desorb (i.e. purge) the evaporated fuel absorbed in the canister  1 . 
     &lt;Main Chamber&gt; 
     The main chamber  3  stores the first adsorbent  7 , and adsorbs the evaporated fuel taken in from the charge port  2 A. The main chamber  3  also discharges the adsorbed evaporated fuel from the purge port  2 B. 
     The main chamber  3  is defined by a first filter  3 A, a second filter  3 B, and a third filter  3 C arranged inside the housing  10  of the canister  1 . The first filter  3 A separates the charge port  2 A connected to the main chamber  3  from a storage space for the adsorbent of the main chamber  3 . The second filter  3 B separates the purge port  2 B connected to the main chamber  3  from the storage space for the adsorbent of the main chamber  3 . 
     The third filter  3 C separates an inner space of the flow path forming member  11  connected to the main chamber  3  from the storage space for the adsorbent in the main chamber  3 . The third filter  3 C is pressed toward the charge port  2 A and the purge port  2 B by a first spring  12  through the flow path forming member  11 . 
     The first filter  3 A, the second filter  3 B, and the third filter  3 C are configured to allow gas to pass through while not allowing the first adsorbent  7  to pass through. That is, the filters  3 A,  3 B, and  3 C hold the first adsorbent  7  therebetween in the main chamber  3 . 
     &lt;Sub Chamber&gt; 
     The sub chamber  4  stores the second adsorbent  8 , and communicates with the main chamber  3  so that gas can flow freely between the main chamber  3  through the intermediate chamber  5  and the communicating passage  6 . The sub chamber  4  is arranged side by side with the main chamber  3  in a radial direction of the main chamber  3  so that a gas flow direction is parallel to the main chamber  3 . 
     The sub chamber  4  is defined by a first filter  4 A and a second filter  4 B arranged inside the housing  10  of the canister  1 . The first filter  4 A separates the atmosphere port  2 C connected to the sub chamber  4  from a storage space for the adsorbent of the sub chamber  4 . The second filter  4 B separates the communicating passage  6  from the storage space for the adsorbent of the sub chamber  4 . 
     The second filter  4 B is pressed toward the atmosphere port  2 C by a second spring  14  through a resin grid  13  having a grid shape. The first filter  4 A and the second filter  4 B defining the sub chamber  4  have functions similar to those of the filters  3 A,  3 B, and  3 C of the main chamber  3 . 
     &lt;Intermediate Chamber&gt; 
     The intermediate chamber  5  stores the third adsorbent  9 , and is arranged between the main chamber  3  and the sub chamber  4  in a flow path of the evaporated fuel. 
     The intermediate chamber  5  is defined by a first filter  5 A and a second filter  5 B arranged inside the resin flow path forming member  11  connected to an end (i.e. the third filter  3 C) opposite the charge port  2 A of the main chamber  3 . That is, the intermediate chamber  5  is arranged inside the flow path forming member  11 , in  FIG.  2 A  and  FIG.  2 B , the flow path forming member  11  has a tapered portion  11 A and a cylindrical portion  11 B. 
     The tapered portion  11 A is a portion having an inner space  11 C gradually reduced in diameter toward a side opposite the main chamber  3 . The tapered portion  11 A is pressed toward the third filter  3 C by the first spring  12  (see  FIG.  1   ). That is, the first spring  12  presses the flow path forming member  11  toward the main chamber  3 . 
     In the inner space  11 C of the tapered portion  11 A, a rib  11 D is arranged. The rib  11 D is formed into a grid shape through which the evaporated fuel F can pass. The rib  11 D supports the first filter  5 A. 
     The cylindrical portion  11 B is connected to an end of the tapered portion  11 A opposite the main chamber  3 . The cylindrical portion  11 B is a pipe body having a circular cross section. The intermediate chamber  5  is configured of a part of an inner space of the cylindrical portion  11 B. 
     The first filter  5 A separates the inner space  11 C of the tapered portion  11 A from a storage space for the adsorbent of the intermediate chamber  5 . The second filter  5 B separates the communicating passage  6  from the storage space for the adsorbent of the intermediate chamber  5 . 
     Each of the first filter  5 A and the second filter  5 B is arranged inside the cylindrical portion  11 B. The second filter  5 B is pressed toward the main chamber  3  by a third spring  16  through a resin grid  15  having a grid shape. The first filter  5 A and the second filter  5 B defining the intermediate chamber  5  have functions similar to those of the filters  3 A,  3 B, and  3 C of the main chamber  3 . 
     The intermediate chamber  5  is connected to the main chamber  3  through the inner space of the tapered portion  11 A. The intermediate chamber  5  is also connected to the sub chamber  4  through a space forming the communicating passage  6 . That is, there are buffer spaces without an adsorbent between the intermediate chamber  5  and the main chamber  3 , and between the intermediate chamber  5  and the sub chamber  4 . These buffer spaces can delay the discharge of the evaporated fuel to the atmosphere. 
     &lt;Communicating Passage&gt; 
     The communicating passage  6  is a space to connect the sub chamber  4  and the intermediate chamber  5  to communicate with each other. The sub chamber  4  communicates with the main chamber  3  through the intermediate chamber  5  and the communicating passage  6 . The only flow path to connect the main chamber  3  and the sub chamber  4  is a flow path composed of the intermediate chamber  5  and the communicating passage  6 . 
     The evaporated fuel taken in from the charge port  2 A is adsorbed into the first adsorbent  7  in the main chamber  3 . The evaporated fuel that was not adsorbed in the main chamber  3  moves through the tapered portion  11 A of the flow path forming member  11  to the intermediate chamber  5  and is adsorbed into the third adsorbent  9  in the intermediate chamber  5 . 
     Furthermore, the evaporated fuel that was not adsorbed in the intermediate chamber  5  moves through the communicating passage  6  to the sub chamber  4 , and is adsorbed into the second adsorbent  8  in the sub chamber  4 . The gas from which the evaporated fuel was adsorbed is released from the atmosphere port  2 C. 
     By supplying the air from the atmosphere port  2 C, the evaporated fuel adsorbed into the adsorbent in each of the sub chamber  4 , the intermediate chamber  5 , and the main chamber  3  by is discharged from the purge port  2 B to the engine. As a result, the air containing the evaporated fuel is supplied to the engine. 
     &lt;Dimensions of Each Chamber&gt; 
     The relations of a length L 1  of the main chamber in the gas flow direction  3 , a length L 2  of the sub chamber  4  in the gas flow direction, and a length L 3  of the intermediate chamber  5  in the gas flow direction shown in  FIG.  1    are described below in Expression (1). 
       L2&gt;L3, L1&gt;L3   (1)
 
     That is, the length L 3  of the intermediate chamber  5  is less than the length L 2  of the sub chamber  4  and the length L 1  of the main chamber  3 . In the present embodiment, the length L 2  is less than the length L 1  (L 2 &lt;L 1 ); however, the length L 2  may be equal to or more than the length L 1  (L 2 ≥L). 
     The relations of an equivalent diameter D 1  in a cross section perpendicular to the gas flow direction in the main chamber  3 , an equivalent diameter D 2  in a cross section perpendicular to the gas flow direction in the sub chamber  4 , and an equivalent diameter D 3  in a cross section perpendicular to the gas flow direction in the intermediate chamber  5  shown in  FIG.  3 A  and  FIG.  3 B  are described below in Equation (2). 
       D2≥D3, D1&gt;D3   (2)
 
     That is, the equivalent diameter D 3  of the intermediate chamber  5  is equal to or less than the equivalent diameter D 2  of the sub chamber  4 , and less than the equivalent diameter D 1  of the main chamber  3 . In the present embodiment, the equivalent diameter D 2  is less than the equivalent diameter D 1  (D 2 &lt;D 1 ); however, the equivalent diameter D 2  may be equal to or more than the equivalent diameter D (D 2 ≥D 1 ). 
     In the intermediate chamber  5 , a ratio of the length L 3  [mm] to the equivalent diameter D 3  [mm], i.e. L 3 /D 3  is equal to or less than 1. On the other hand, a ratio of the length L 2  [mm] to the equivalent diameter D 2  [mm] in the sub chamber  4 , i.e. L 2 /D 2  is more than 1, and a ratio of the length L 1  [mm] to the equivalent diameter D 1  [mm] in the main chamber  3 , i.e. L 1 /D 1  is more than 1. 
     &lt;Adsorbent&gt; 
     Each of the first adsorbent  7 , the second adsorbent  8 , and the third adsorbent  9  adsorbs the evaporated fuel and butane supplied with the air and the like to the canister  1 . These adsorbents desorb the evaporated fuel and the butane by the introduced external air. The desorbed evaporated fuel is supplied to the engine. 
     Examples of the material of the first adsorbent  7 , the second adsorbent  8 , and the third adsorbent  9  may include well-known materials, such as activated carbon. Examples of the activated carbon may include an aggregate of granular activated carbon, a honeycomb-shaped molded activated carbon, and fibrous activated carbon molded into a sheet shape, a rectangular parallelepiped shape, a circular columnar shape, and a rectangular columnar shape. 
     An adsorption capacity of the third adsorbent  9  as a whole stored in the intermediate chamber  5  is smaller than an adsorption capacity of the first adsorbent  7  as a whole stored in the main chamber  3  and an adsorption capacity of the second adsorbent  8  as a whole stored in the sub chamber  4 . 
     Here, “the adsorption capacity of the adsorbent as a whole” is obtained by multiplying an amount of evaporated fuel that the adsorbent per unit volume can adsorb by a volume of the adsorbent stored in each chamber. Therefore, the adsorption capacity of the adsorbent as a whole in each chamber can be adjusted by changing the adsorbent in each chamber to an adsorbent with a different adsorption capacity per unit volume, and/or by changing the volume of the adsorbent stored in each chamber. 
     Therefore, for the first adsorbent  7 , the second adsorbent  8 , and the third adsorbent  9 , the same type of adsorbent may be used, or different types of adsorbent may be used. 
     After purging, the intermediate chamber  5  is required to be in a state where the evaporated fuel is not adsorbed. Thus, if the adsorption capacity of the intermediate chamber  5  is too high, the evaporated fuel remains after purging, which affects an adsorption performance later. In addition, from the viewpoint of downsizing of the canister  1 , the intermediate chamber  5  should be made compact. From these perspectives, the adsorption capacity of the intermediate chamber  5  is made smaller than that of the main chamber  3 . Furthermore, if the adsorption capacity of the intermediate chamber  5  is made small, the desorption of the evaporated fuel from the adsorbent improves. 
     [1-2. Effects] 
     In the embodiment detailed above, following effects can be obtained. 
     (1a) With the intermediate chamber  5 , it is possible to delay the moving of the evaporated fuel, which was not adsorbed in the main chamber  3 , to the sub chamber  4 . Thus, it is possible to reduce the discharge of the evaporated fuel to the atmosphere. The adsorption capacity of the third adsorbent  9  as a whole in the intermediate chamber  5  is made smaller than the adsorption capacity of the first adsorbent  7  as a whole and the adsorption capacity of the second adsorbent  8  as a whole, and thus, the intermediate chamber  5  can be made compact. As a result, it is possible to inhibit the upsizing of the canister  1  while reducing the discharge of the evaporated fuel to the atmosphere. 
     (1b) Since the ratio of L 3 /D 3  in the intermediate chamber  5  is equal to or less than 1, the ventilation resistance of the intermediate chamber  5  can be reduced. In addition, the length of the intermediate chamber  5  can be reduced, which promotes the effect of inhibiting the upsizing of the canister  1 . 
     (1c) The equivalent diameter D 3  of the intermediate chamber  5  is equal to or less than the equivalent diameter D 2  of the sub chamber  4  and less than the equivalent diameter D 1  of the main chamber  3 , which enhances the desorption properties of the third adsorbent  9  in the intermediate chamber  5 . As a result, an adsorption effect of the intermediate chamber  5  at the time of re-absorption of the evaporated fuel increases, which promotes the effect of reducing the discharge of the evaporated fuel to the atmosphere. 
     (1d) The intermediate chamber  5  is arranged inside the flow path forming member  11 , which allows to form the intermediate chamber  5  utilizing a part of the structure of the flow path. Thus, it is possible to promote the effect of inhibiting the upsizing of the canister  1 . 
     Second Embodiment 
     [2-1. Configuration] 
     A canister  101  shown in  FIG.  4    adsorbs and desorbs the evaporated fuel occurred in the fuel tank of the vehicle. The canister  101  includes a charge port  2 A, a purge port  2 B, an atmosphere port  2 C, a main chamber  3 , a sub chamber  4 , an intermediate chamber  105 , a communicating passage  106 , a first adsorbent  7 , a second adsorbent  8 , and a third adsorbent  9 . 
     The charge port  2 A, purge port  2 B, atmosphere port  2 C, main chamber  3 , sub chamber  4  and adsorbents  7 ,  8 ,  9  of the canister  101  are the same as those of the canister  1  of  FIG.  1   . Therefore, the same reference numerals are given to these components and the description thereof is omitted. In the present embodiment, the third filter  3 C separating the main chamber  3  is pressed by a resin grid  111  having a grid shape instead of the flow path forming member  11  of  FIG.  1   . 
     &lt;Intermediate Chamber&gt; 
     The intermediate chamber  105  is arranged between the main chamber  3  and the sub chamber  4  in the flow path of the evaporated fuel and is connected to each of the main chamber  3  and the sub chamber  4  through spaces. 
     The intermediate chamber  105  is arranged inside a crank portion  106 A of the communicating passage  106 . Specifically, the intermediate chamber  105  is defined by a first filter  105 A and a second filter  105 B arranged in an intermediate part of the crank portion  106 A. 
     The first filter  105 A separates an area near the main chamber  3  in the communicating passage  106  from a storage space for the adsorbent of the intermediate chamber  105 . The second filter  105 B separates an area near the sub chamber  4  in the communicating passage  106  from the storage space for the adsorbent of the intermediate chamber  105 . 
     The first filter  105 A is pressed toward the second filter  105 B by a third spring  116  through a resin grid  115  having a grid shape. The second filter  105 B is supported by an interior wall constituting the crank portion  106 A of the communicating passage  106 . 
     In the intermediate chamber  105 , a third adsorbent  9  the same as that of the first embodiment is stored. The relations between the length and equivalent diameter of the intermediate chamber  105  and the length and equivalent diameter of each of the main chamber  3  and the sub chamber  4  are the same as those of the first embodiment. 
     &lt;Communicating Passage&gt; 
     The communicating passage  106  is a space to connect main chamber  3  and the sub chamber  4  to communicate with each other. The communicating passage  106  has the S-shaped crank portion  106 A. 
     In the crank portion  106 A, a direction of the gas flow passed through the main chamber  3  is bent from a radial direction of the main chamber  3  (i.e. in an up-down direction of  FIG.  4   ) to a direction parallel to the gas flow direction in the main chamber  3  (i.e. in a left-right direction of  FIG.  4   ), and thereafter, the direction is further bent to the radial direction of the main chamber  3 . 
     In the crank portion  106 A, the intermediate part in which the gas flow direction is parallel to the gas flow direction in the main chamber  3  has the intermediate chamber  105  arranged therein as described above. The intermediate part (i.e. the intermediate chamber  105 ) of the crank portion  106 A is arranged between the main chamber  3  and the sub chamber  4  in the radial direction of the main chamber  3 . 
     [2-2. Effects] 
     In the embodiment detailed above, following effects can be obtained. 
     (2a) The intermediate chamber  105  can be formed by utilizing a part of the communicating passage  106 . Thus, it is possible to promote the effect of inhibiting the upsizing of the canister  101 . The intermediate chamber  105  is arranged in the crank portion  106 A of the communicating passage  106 , which makes it possible for the main chamber  3  and the sub chamber  4  to have structures similar to the conventional structures. 
     3. Third Embodiment 
     [3-1. Configuration] 
     A canister  201  shown in  FIG.  5    adsorbs and desorbs the evaporated fuel occurred in the fuel tank of the vehicle. The canister  201  includes a charge port  2 A, a purge port  2 B, an atmosphere port  2 C, a main chamber  3 , a sub chamber  4 , an intermediate chamber  205 , a communicating passage  206 , a first adsorbent  7 , a second adsorbent  8 , and a third adsorbent  9 . 
     The charge port  2 A, purge port  2 B, atmosphere port  2 C, main chamber  3 , sub chamber  4  and adsorbents  7 ,  8 ,  9  of the canister  201  are the same as those of the canister  101  of  FIG.  4   . Therefore, the same reference numerals are given to these components and the description thereof is omitted. 
     &lt;Intermediate Chamber&gt; 
     The intermediate chamber  205  is arranged between the main chamber  3  and the sub chamber  4  in the flow path of the evaporated fuel and is connected to each of the main chamber  3  and the sub chamber  4  through spaces. 
     The intermediate chamber  205  is arranged in the linear part  206 A of the communicating passage  206 . Specifically, the intermediate chamber  205  is defined by a first filter  205 A and a second filter  205 B arranged in the linear part  206 A. 
     The first filter  205 A separates an area near the main chamber  3  in the linear part  206 A from a storage space for the adsorbent of the intermediate chamber  205 . The second filter  205 B separates an area near the sub chamber  4  in the linear part  206 A from the storage space for the adsorbent of the intermediate chamber  205 . 
     The first filter  205 A is pressed toward the sub chamber  4  by a third spring  216  through a resin grid  215  having a grid shape. In this embodiment, the third spring  216  also serves as a spring (i.e. the second spring  14  of  FIG.  4   ) pressing the second filter  4 B defining the sub chamber  4 . 
     The second filter  205 B is pressed by a resin partition grid  2 B arranged between the sub chamber  4  and the intermediate chamber  205 . As shown in  FIG.  6   , the partition grid  2 B has a three-dimensional grid shape. 
     The partition grid  2 B passes the evaporated fuel in the direction the same as the gas flow direction in the sub chamber  4 . With the partition grid  2 B, a buffer space without an adsorbent is arranged between the sub chamber  4  and the intermediate chamber  205 . This buffer space can delay the discharge of the evaporated fuel to the atmosphere. 
     As shown in  FIG.  5   , in the intermediate chamber  205 , a third adsorbent the same as that of the first embodiment is stored. The relations between the length and equivalent diameter of the intermediate chamber  205  and the length and equivalent diameter of each of the main chamber  3  and the sub chamber  4  are the same as those of the first embodiment. 
     &lt;Communicating Passage&gt; 
     The communicating passage  206  is a space to connect the main chamber  3  and the sub chamber  4  to communicate with each other. The communicating passage  206  has a linear part  206 A that is aligned linearly with the sub chamber  4  on the side opposite the atmosphere port  2 C of the sub chamber  4 . 
     The gas flow direction in the linear part  206 A is parallel to the gas flow direction in the sub chamber  4 . The linear part  206 A overlaps with the sub chamber  4  in the gas flow direction of the sub chamber  4  (i.e. in the left-right direction in  FIG.  5   ). In the linear part  206 A, the intermediate chamber  205  and the partition grid  2 B are arranged as described above. The intermediate chamber  205  is arranged so as to be shifted from the main chamber  3  in the radial direction of the main chamber  3 . 
     [3-2. Effects] 
     In the embodiment detailed above, following effects can be obtained. 
     (3a) The intermediate chamber  205  can be formed by utilizing a part of he communicating passage  206 . Thus, it is possible to promote the effect of inhibiting the upsizing of the canister  201 . The intermediate chamber  205  is arranged in the linear part  206 A of the communicating passage  206 , which makes it easy to arrange the intermediate chamber  205  and to hold the third adsorbent  9 . 
     4. Other Embodiments 
     Although the embodiments of the present disclosure have been described above, it should be appreciated that the present disclosure is not limited to the above embodiments and can take various forms. 
     (4a) The canister of any one of the above described embodiments may additionally include an auxiliary chamber storing an adsorbent between the sub chamber and the atmosphere port. That is, the atmosphere port may be connected to the sub chamber through another chamber (i.e. the auxiliary chamber). 
     (4b) A function served by a single element in any of the above-described embodiments may be achieved by a plurality of elements, or a function served by a plurality of elements may be achieved by a single element. A part of the configurations of the aforementioned embodiments may be omitted. At least part of the configurations of the aforementioned embodiments may be added to or replaced with the configurations of the other above-described embodiments. It should be noted that all modes included in the technical idea specified from the wording described in the claims are embodiments of the present disclosure.