Evaporated fuel processing device

Abstract

To suppress generation of a gap between an inner surface of a case and an outer surface of an adsorbent, in an evaporated fuel treatment device including the massive adsorbent.SOLUTION: The evaporated fuel processing device includes an adsorbent, an inner case, an outer case, and an elastic member. The adsorbent is massive. The adsorbent is configured to adsorb the evaporated fuel. The inner case has a tubular shape. The inner case is configured to hold the adsorbent in a state where at least a part of the adsorbent is disposed inside the inner case. The outer case accommodates the adsorbent and the inner case. The elastic member is disposed between the outer surface of the inner case and the inner surface of the outer case. The elastic member surrounds both the inner case and the adsorbent in the circumferential direction of the inner case.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a fuel vapor treatment system. [Background technology]

[0002] For example, Patent Document 1 describes an evaporated fuel treatment device including a case and granular activated carbon. The activated carbon is configured to adsorb evaporated fuel. The activated carbon is packed into the case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 6-25546 Summary of the Invention [Problem to be solved by the invention]

[0004] The fuel vapor treatment device may include a block of adsorbent material that is configured to adsorb fuel vapor and is disposed inside a case.

[0005] In this type of evaporated fuel treatment device, when the case expands due to heat, it is conceivable that a gap will be formed between the inner surface of the case and the outer surface of the adsorbent.

[0006] In one aspect of the present disclosure, in an evaporated fuel treatment device including a block of adsorbent, it is desirable to suppress the occurrence of a gap between the inner surface of the case and the outer surface of the adsorbent. [Means for solving the problem]

[0007] One aspect of the present disclosure is an evaporated fuel treatment device comprising an adsorbent, an inner case, an outer case, and an elastic member. The adsorbent is in a block form. The adsorbent is configured to adsorb evaporated fuel. The inner case is cylindrical. The inner case is configured to hold the adsorbent with at least a portion of the adsorbent disposed therein. The outer case houses the adsorbent and the inner case. The elastic member is disposed between an outer surface of the inner case and an inner surface of the outer case. The elastic member surrounds both the inner case and the adsorbent in the circumferential direction of the inner case.

[0008] According to this configuration, in an evaporated fuel treatment device including a block of adsorbent, it is possible to prevent the formation of a gap between the inner surface of the inner case and the outer surface of the adsorbent.

[0009] In one aspect of the present disclosure, the length of the adsorbent along the gas flow direction may be smaller than the equivalent diameter of a cross section of the adsorbent perpendicular to the gas flow direction. This configuration reduces the airflow resistance of the adsorbent while preventing the formation of a gap between the inner surface of the inner case and the outer surface of the adsorbent.

[0010] In one aspect of the present disclosure, the outer case may have an atmosphere port that is open to the atmosphere and an atmosphere-side adsorption chamber that is directly connected to the atmosphere port. The adsorbent and the elastic member may be housed in the atmosphere-side adsorption chamber. With this configuration, it is possible to prevent a gap from being formed between the inner surface of the inner case and the outer surface of the adsorbent adjacent to the atmosphere port. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic cross-sectional view of an evaporated fuel treatment device according to a first embodiment. [Figure 2] 2 is a schematic cross-sectional view of the vicinity of a third adsorption chamber of the evaporated fuel treatment device of the first embodiment. FIG. [Figure 3]3A and 3B are schematic cross-sectional views showing a state in which an outer case expands due to heat in the evaporated fuel treatment device of the first embodiment, and an inner case attempts to expand due to heat in the evaporated fuel treatment device of the first embodiment. [Figure 4] FIG. 6 is a schematic cross-sectional view of the vicinity of a third adsorption chamber of an evaporated fuel treatment device according to a second embodiment. [Figure 5] FIG. 10 is a side view of the elastic member of the second embodiment. [Figure 6] FIG. 10 is a schematic cross-sectional view of the vicinity of a second adsorption chamber of an evaporated fuel treatment device according to a third embodiment. [Figure 7] FIG. 10 is a schematic cross-sectional view of the vicinity of a second adsorption chamber of an evaporated fuel treatment device according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings.

[0013] [1. First embodiment] [1-1.Configuration] The evaporated fuel treatment device 1 shown in Fig. 1 is mounted on a vehicle. The evaporated fuel treatment device 1 is configured as a canister that adsorbs and desorbs evaporated fuel generated in the vehicle's fuel tank. The evaporated fuel treatment device 1 includes a first adsorbent 2, a second adsorbent 3, a third adsorbent 4, an outer case 5, an inner case 6, and an elastic member 7.

[0014] The first adsorbent 2, the second adsorbent 3, and the third adsorbent 4 are configured to adsorb evaporated fuel. Of the first adsorbent 2, the second adsorbent 3, and the third adsorbent 4, at least the third adsorbent 4 is in a block shape. A specific example of a block adsorbent is a molded body formed by molding fibrous activated carbon into a block shape. The third adsorbent 4 has a columnar outer shape. The first adsorbent 2 and the second adsorbent 3 may be, for example, in a block shape or in a granular shape. A specific example of a granular adsorbent is an aggregate of granular activated carbon.

[0015] The outer case 5 is a member having an internal space. The outer case 5 is made of, for example, a synthetic resin. Specific examples of synthetic resins include polyamide resins such as PA66. The outer case 5 has a charge port 51, a purge port 52, an atmospheric port 53, a first adsorption chamber 54, a second adsorption chamber 55, a third adsorption chamber 56, and a communication passage 57.

[0016] The charge port 51 is connected to the fuel tank via a pipe. The charge port 51 is configured to take in the evaporated fuel generated in the fuel tank into the evaporated fuel processing device 1. The charge port 51 functions as an inlet for gas containing evaporated fuel.

[0017] The purge port 52 is connected to an intake pipe of the engine of the vehicle via a purge valve, and is configured to supply the evaporated fuel in the evaporated fuel processing device 1 to the engine.

[0018] The atmospheric port 53 is open to the atmosphere. The atmospheric port 53 is configured to release air from which evaporated fuel has been removed into the atmosphere. Furthermore, the atmospheric port 53 is configured to take in outside air (i.e., purge air). When the atmospheric port 53 takes in (i.e., purges) air, the adsorbed evaporated fuel is desorbed and supplied to the engine via the purge port 52.

[0019] The first adsorption chamber 54 is a portion that accommodates the first adsorbent 2. The first adsorption chamber 54 is directly connected to the charge port 51 and the purge port 52. Being directly connected to a port means being connected to the port without going through another chamber. The same applies below. The first adsorption chamber 54 corresponds to the main chamber, which has the largest volume, among the multiple adsorption chambers 54, 55, and 56.

[0020] The second adsorption chamber 55 is a portion that accommodates the second adsorbent 3. The second adsorption chamber 55 corresponds to an auxiliary chamber with a smaller volume than the first adsorption chamber 54. The second adsorption chamber 55 communicates with the first adsorption chamber 54 via a communication passage 57. The second adsorption chamber 55 communicates with a third adsorption chamber 56 on the side opposite to the communication passage 57.

[0021] The third adsorption chamber 56 is a portion that accommodates the third adsorbent 4. Like the second adsorption chamber 55, the third adsorption chamber 56 corresponds to an auxiliary chamber that has a smaller volume than the first adsorption chamber 54. As shown in FIG. 2 , the third adsorption chamber 56 has a main body portion 561, a lid portion 562, at least one bottom support portion 563, and at least one lid support portion 564.

[0022] The main body 561 is a cylindrical portion with a bottom. The main body 561 may be, for example, a cylindrical portion with a bottom or a rectangular portion with a bottom. The main body 561 has a peripheral wall 5611 and a bottom wall 5612. The peripheral wall 5611 is a cylindrical portion. The third adsorbent 4 is disposed in a space surrounded by the peripheral wall 5611. The bottom wall 5612 is a plate-like portion. Of the two openings in the axial direction of the peripheral wall 5611, the bottom wall 5612 partially closes the opening on the second adsorption chamber 55 side. A communication hole 565 communicating with the second adsorption chamber 55 is formed in the center of the bottom wall 5612.

[0023] The lid portion 562 is configured to partially close the opening of the main body portion 561, which is a cylindrical body portion with a bottom. In other words, the opening of the main body portion 561 is the opening opposite the opening closed by the bottom wall 5612, of the two openings in the axial direction of the peripheral wall 5611. The lid portion 562 is fixed to the main body portion 561 in a state in which it closes the opening of the main body portion 561. The lid portion 562 is provided with an atmospheric port 53. In other words, the third adsorption chamber 56 is directly connected to the atmospheric port 53. The third adsorption chamber 56 corresponds to an example of an atmospheric-side adsorption chamber. The flow direction of the gas in the third adsorption chamber 56 coincides with the axial direction of the main body portion 561.

[0024] The bottom-side support portion 563 is a portion that protrudes from the bottom wall 5612 toward the lid portion 562. The lid-side support portion 564 is a portion that protrudes from the lid portion 562 toward the bottom wall 5612. The bottom-side support portion 563 and the lid-side support portion 564 are configured to suppress movement of the third adsorbent 4 in the axial direction of the main body portion 561 when the third adsorbent 4 is housed in the main body portion 561. Note that the bottom-side support portion 563 and the lid-side support portion 564 are not shown in Figures 3A and 3B.

[0025] As shown in FIG. 1 , in the evaporated fuel treatment device 1, a flow path F for gas containing evaporated fuel is formed by the first adsorption chamber 54, the connecting passage 57, the second adsorption chamber 55, and the third adsorption chamber 56. In this embodiment, the flow path F is U-shaped, folded back at the connecting passage 57. The second adsorption chamber 55 and the third adsorption chamber 56 are arranged in series in the gas flow direction. As an example, the second adsorption chamber 55 and the third adsorption chamber 56 are arranged on the same straight line. The first adsorption chamber 54 is arranged side by side with the second adsorption chamber 55 and the third adsorption chamber 56. The gas flow directions in the first adsorption chamber 54, the second adsorption chamber 55, and the third adsorption chamber 56 are parallel to each other. The gas flow directions in the first adsorption chamber 54, the second adsorption chamber 55, and the third adsorption chamber 56 correspond to the left-right direction in the drawing.

[0026] As shown in FIG. 2, the inner case 6 is a tubular member. The inner case 6 may be, for example, cylindrical or rectangular. The inner case 6 is made of, for example, a synthetic resin. The material of the inner case 6 may be, for example, the same as or different from that of the outer case 5. The thermal expansion coefficient (linear expansion coefficient) of the inner case 6 is preferably the same as or larger than that of the outer case 5, and more preferably larger than that of the outer case 5.

[0027] The inner case 6 has a peripheral wall 61 and a groove 62 .

[0028] The peripheral wall 61 is a cylindrical portion. In the following, of the two surfaces of the peripheral wall 61 that surround the central axis of the peripheral wall 61 and extend along the central axis of the peripheral wall 61, the radially outer surface will be referred to as the outer surface of the peripheral wall 61, and the radially inner surface will be referred to as the inner surface of the peripheral wall 61.

[0029] The groove 62 is a recess provided on the outer surface of the peripheral wall 61. The groove 62 is continuous around the entire circumference in the circumferential direction. As will be described later, at least a portion of the third adsorbent 4 is disposed in the space surrounded by the peripheral wall 61, and the groove 62 is provided in a portion of the peripheral wall 61 that surrounds the third adsorbent 4 in the circumferential direction. As an example, the groove 62 is provided in the central portion of the peripheral wall 61 in the axial direction of the peripheral wall 61.

[0030] At least a portion (all of the third adsorbent in this embodiment) of the third adsorbent 4 is disposed in the space surrounded by the peripheral wall 61. That is, at least a portion (all of the third adsorbent in this embodiment) of the third adsorbent 4 is disposed inside the inner case 6. The inner case 6 is configured to hold the third adsorbent 4 with at least a portion of the third adsorbent 4 disposed inside. As an example, by press-fitting at least a portion of the third adsorbent 4 into the inner case 6, the inner case 6 is able to hold the third adsorbent 4 with at least a portion of the third adsorbent 4 disposed inside the inner case 6. The inner surface of the peripheral wall 61 is in contact with the surface of the third adsorbent 4 that faces the inner surface of the peripheral wall 61 over the entire circumferential direction.

[0031] The inner case 6 is housed in the third adsorption chamber 56 while holding the third adsorbent 4. That is, both the inner case 6 and the third adsorbent 4 are housed in the third adsorption chamber 56. The central axis of the inner case 6 coincides with the central axis of the main body 561. The gas that has flowed into the third adsorption chamber 56 passes through the inside of the inner case 6, and ultimately through the third adsorbent 4, in the axial direction of the inner case 6.

[0032] In a state where the third adsorbent 4 is held in the inner case 6, the length L [mm] of the third adsorbent 4 is smaller than the equivalent diameter D [mm] of the cross section of the third adsorbent 4. More specifically, the length L of the third adsorbent 4 is the length L of the third adsorbent 4 along the direction of gas flow in the third adsorption chamber 56. More specifically, the equivalent diameter D of the cross section of the third adsorbent 4 is the equivalent diameter D of a cross section of the third adsorbent 4 that is perpendicular to the direction of gas flow in the third adsorption chamber 56. The equivalent diameter D of the cross section is the diameter of a perfect circle having the same area S as the cross section (D=(S / π) 1 / 2 × 2) in the direction of gas flow. The same applies below.

[0033] The elastic member 7 is an annular member having elasticity. The term "annular" here means a shape that is continuous around the entire circumference in the circumferential direction. The term "annular" here includes a shape whose outer shape is circular when viewed from the axial direction and a shape whose outer shape is polygonal when viewed from the axial direction. The elastic member 7 is configured to prevent the passage of evaporated fuel. The elastic member 7 is made of, for example, an elastomer. A specific example of the elastic member 7 is an O-ring.

[0034] The elastic member 7 is disposed in the groove 62. Before the inner case 6 is housed in the outer case 5, the elastic member 7 disposed in the groove 62 protrudes radially outward from the peripheral wall 61. In other words, before the inner case 6 is housed in the outer case 5, the dimension from the central axis of the peripheral wall 61 to the radially outer edge of the elastic member 7 is greater than the dimension from the central axis of the peripheral wall 61 to the outer surface of the peripheral wall 61. Therefore, when the inner case 6 is housed in the outer case 5 with the elastic member 7 disposed in the groove 62, the elastic member 7 is disposed between the outer surface of the inner case 6 and the inner surface of the outer case 5 in a state where it is radially compressed by the outer case 5. Furthermore, as described above, the groove 62 is provided at a position that surrounds the third adsorbent 4 in the circumferential direction of the inner case 6. Therefore, the elastic member 7 surrounds both the inner case 6 and the third adsorbent 4 in the circumferential direction of the inner case 6. The elastic member 7 covers a partial range of the inner case 6 in the axial direction of the inner case 6 from the radial outside of the inner case 6. The elastic member 7 covers a partial range of the third adsorbent 4 in the axial direction of the inner case 6 from the radial outside of the inner case 6.

[0035] The inner case 6 is designed to have a size such that, when housed in the outer case 5, a gap is formed between the outer surface of the peripheral wall 61 and the inner surface of the main body 561. However, due to dimensional errors in the inner case 6 or the outer case 5, it is possible that the outer surface of the peripheral wall 61 may come into partial contact with the inner surface of the main body 561.

[0036] [1-2. Effect] For example, a heat source such as a vehicle muffler is disposed around the evaporated fuel treatment device 1. In this case, it is conceivable that heat from the heat source is transferred to the evaporated fuel treatment device 1. Specifically, the heat from the heat source may be transferred from the outside to the inside of the evaporated fuel treatment device 1. Therefore, it is conceivable that heat is transferred in the order of, for example, the outer case 5, the inner case 6, and the third adsorbent 4.

[0037] When heat is transferred to the outer case 5, the outer case 5 may expand due to the heat, as indicated by the white arrow in Fig. 3A. If the thermal expansion coefficients of the outer case 5 and the inner case 6 are roughly the same, the outer case 5, which is closer to the heat source, is more likely to expand than the inner case 6.

[0038] For example, in the outer case 5, when the third adsorption chamber 56 expands due to heat, the elastic member 7 expands radially accordingly. This is because the compressive force acting on the elastic member 7 from the outer case 5 weakens. As the elastic member 7 expands radially, the positions of the inner case 6 and the third adsorption material 4 relative to the third adsorption chamber 56 are less likely to change.

[0039] If heat is transmitted to the inner case 6 after being transmitted to the outer case 5, it is conceivable that the inner case 6 will expand due to the heat. If the inner case 6 expands due to the heat, a gap may form between the inner surface of the inner case 6 and the outer surface of the third adsorbent 4. If a gap forms, some of the evaporated fuel may pass through the gap instead of the third adsorbent 4, which may reduce the evaporated fuel adsorption performance of the evaporated fuel treatment device 1. Furthermore, if a gap forms, the position of the third adsorbent 4 relative to the inner case 6 may become misaligned.

[0040] However, when the inner case 6 attempts to expand, as shown in FIG. 3B , a compressive force Y1 acts from the inner case 6 to the elastic member 7. Accordingly, a reaction force Y2 acts from the elastic member 7 to the inner case 6. The reaction force Y2 presses the inner case 6 radially inward, i.e., toward the third adsorbent 4. The reaction force Y2 acts particularly on the portion of the inner case 6 where the inner surface of the inner case 6 faces the outer surface of the third adsorbent 4. This is because the elastic member 7 surrounds both the inner case 6 and the third adsorbent 4 in the circumferential direction of the inner case 6. Therefore, the reaction force Y2 particularly suppresses radial expansion of the portion of the inner case 6 where the inner surface of the inner case 6 faces the outer surface of the third adsorbent 4. As a result, the formation of a gap between the inner surface of the inner case 6 and the outer surface of the third adsorbent 4 is suppressed.

[0041] [1-3.Effects] According to the first embodiment described above in detail, the following effects can be obtained.

[0042] (1a) The evaporated fuel treatment device 1 includes an elastic member 7. The elastic member 7 is disposed between the outer surface of the inner case 6 and the inner surface of the outer case 5. Specifically, the elastic member 7 is disposed between the outer surface of the peripheral wall 61 and the inner surface of the main body 561. The elastic member 7 surrounds both the inner case 6 and the third adsorbent 4 in the circumferential direction of the inner case 6.

[0043] With this configuration, even if the inner case 6 were to expand due to heat, a compressive force Y1 would act on the elastic member 7, causing a reaction force Y2 to act on the inner case 6. This makes it possible to suppress expansion of the inner case 6 due to heat. In particular, it is possible to suppress expansion of the portion of the inner case 6 where the inner surface of the inner case 6 faces the outer surface of the third adsorbent 4. As a result, it is possible to suppress the generation of a gap between the inner surface of the inner case 6 and the outer surface of the third adsorbent 4. This contributes to preventing a decrease in the evaporated fuel adsorption performance of the evaporated fuel treatment device 1 and preventing the third adsorbent 4 from shifting in position relative to the inner case 6.

[0044] (1b) The thermal expansion coefficient of the inner case 6 is, for example, the same as or greater than the thermal expansion coefficient of the outer case 5. With this configuration, it is possible to make the outer case 5 less likely to expand relative to the inner case 6. Therefore, when heat is transferred to the outer case 5 and the inner case 6 and they attempt to expand, a greater compressive force Y1 can be applied to the elastic member 7. As a result, a greater reaction force Y2 can be applied to the inner case 6. Consequently, it is possible to further prevent a gap from being formed between the inner surface of the inner case 6 and the outer surface of the third adsorbent 4.

[0045] (1c) At least a portion of the third adsorbent 4 is, for example, press-fit into the inner case 6. In other words, at least a portion of the third adsorbent 4 is disposed inside the inner case 6 in a state where it is, for example, compressed in the radial direction by the inner case 6. With this configuration, even if the inner case 6 expands due to heat, the third adsorbent 4 expands in the radial direction by that amount. Therefore, it is possible to further prevent a gap from being formed between the inner surface of the inner case 6 and the outer surface of the third adsorbent 4.

[0046] (1d) The inner case 6 has a groove 62. The elastic member 7 is disposed in the groove 62. With this configuration, it is possible to prevent the elastic member 7 from being displaced in the axial direction of the inner case 6. Therefore, it is possible to more easily obtain the effect of (1a) above.

[0047] (1e) The length L of the third adsorbent 4 is smaller than the equivalent diameter D of the cross section of the third adsorbent 4. With this configuration, the airflow resistance of the third adsorbent 4 can be further reduced, while the effect of (1a) above can be obtained.

[0048] (1f) The third adsorbent 4 and the elastic member 7 are housed in a third adsorption chamber 56. The third adsorption chamber 56 is directly connected to the atmospheric port 53. With this configuration, the effect of (1a) above can be obtained for the third adsorbent 4 adjacent to the atmospheric port 53.

[0049] [2. Second Embodiment] [2-1.Configuration] The second embodiment has the same basic configuration as the first embodiment, so differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and reference is made to the preceding description.

[0050] As shown in FIG. 4, the evaporated fuel processing device 1A of the second embodiment differs from the evaporated fuel processing device 1 of the first embodiment in that it includes an inner case 6A and an elastic member 7A instead of the inner case 6 and elastic member 7 described above.

[0051] The inner case 6A has substantially the same configuration as the above-described inner case 6. However, the inner case 6A does not have the groove 62.

[0052] The elastic member 7A is a cylindrical member having elasticity. As shown in Fig. 5, the elastic member 7A has a cylindrical portion 71 and at least one (three in this embodiment) flange portion 72. The cylindrical portion 71 is a cylindrical portion. The flange portion 72 is a portion that protrudes radially outward from the cylindrical portion 71 and is continuous with the entire circumference of the cylindrical portion 71 in the circumferential direction.

[0053] As shown in FIG. 4, the elastic member 7A is disposed between the outer surface of the inner case 6A and the inner surface of the outer case 5 in a state compressed in the radial direction. Specifically, the elastic member 7A is disposed between the outer surface of the inner case 6A and the inner surface of the main body 561 in a state compressed in the radial direction. The elastic member 7A surrounds both the inner case 6A and the third adsorbent 4 in the circumferential direction of the inner case 6A. The elastic member 7A covers the entire area of ​​the inner case 6A in the axial direction of the inner case 6A from the radial outside of the inner case 6A. The elastic member 7A covers the entire area of ​​the third adsorbent 4 in the axial direction of the inner case 6A from the radial outside of the inner case 6A.

[0054] 4 shows, as an example, a configuration in which the flange portion 72 bites into the peripheral wall 5611 of the main body portion 561. However, the elastic member 7A may be housed in the main body portion 561 in a state in which the flange portion 72 does not bite into the peripheral wall 5611, for example, by bending the flange portion 72 radially inward.

[0055] [2-2. Effects] According to the second embodiment described above in detail, the same effects as those of the first embodiment can be obtained, and further, the following effects can be obtained.

[0056] (2a) The elastic member 7A covers the entire area of ​​the inner case 6A in the axial direction of the inner case 6A from the radial outside of the inner case 6A. With this configuration, when the inner case 6A attempts to expand due to heat, a reaction force can be applied to the entire area of ​​the inner case 6A in the axial direction of the inner case 6A. Therefore, the inner case 6A can be further prevented from expanding due to heat. Consequently, the formation of a gap between the inner surface of the inner case 6A and the outer surface of the third adsorbent 4 can be further prevented.

[0057] (2b) The elastic member 7A is provided with at least one flange 72. With this configuration, the position of the elastic member 7A relative to the outer case 5 is less likely to shift compared to a configuration without the flange 72. Therefore, the effect of (2a) above can be more easily achieved.

[0058] 3. Third Embodiment [3-1.Configuration] The third embodiment has the same basic configuration as the first embodiment, so differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and reference is made to the preceding description.

[0059] 6, the evaporated fuel treatment device 1B of the third embodiment includes a second adsorbent 3B instead of the above-described second adsorbent 3. In addition, the evaporated fuel treatment device 1B further includes an inner case 6B and an elastic member 7B.

[0060] The second adsorbent 3B is configured to adsorb evaporated fuel in the same manner as the above-described second adsorbent 3. The second adsorbent 3B is in a block shape. The outer shape of the second adsorbent 3B is columnar.

[0061] The inner case 6B is a cylindrical part with a bottom, and has a peripheral wall 61B, a bottom wall 63, an annular part 64, and a groove part 62B.

[0062] The peripheral wall 61B is a cylindrical portion.

[0063] The bottom wall 63 is a portion that closes one opening in the axial direction of the peripheral wall 61B. The bottom wall 63 is, for example, plate-shaped. The bottom wall 63 has a plurality of through holes 65 formed therein.

[0064] The annular portion 64 is an annular portion. The annular portion 64 protrudes radially outward from the peripheral wall 61B and is continuous along the entire circumferential circumference of the peripheral wall 61B. As will be described later, at least a portion of the second adsorbent 3B is disposed in the space surrounded by the peripheral wall 61B, and the annular portion 64 is provided in a portion of the peripheral wall 61B that circumferentially surrounds the second adsorbent 3B.

[0065] The groove 62B is a recess provided in the end surface of the annular portion 64. The end surface of the annular portion 64 is the radially outer surface of the annular portion 64. The groove 62B is continuous around the entire circumferential direction of the peripheral wall 61B.

[0066] At least a portion (all of the second adsorbent in this embodiment) of the second adsorbent 3B is disposed in the space surrounded by the peripheral wall 61B. That is, at least a portion (all of the second adsorbent in this embodiment) of the second adsorbent 3B is disposed inside the inner case 6B. The inner case 6B is configured to hold the second adsorbent 3B with at least a portion of the second adsorbent 3B disposed inside. As an example, by press-fitting at least a portion of the second adsorbent 3B into the inner case 6B, the inner case 6B can hold the second adsorbent 3B with at least a portion of the second adsorbent 3B disposed inside the inner case 6B.

[0067] The inner case 6B is housed in the second adsorption chamber 55 while holding the second adsorbent 3B. That is, the inner case 6B is housed in the second adsorption chamber 55 together with the second adsorption material 3B. The inner case 6B is housed in the second adsorption chamber 55 with the bottom wall 63 facing the third adsorption chamber 56. The gas that has flowed into the second adsorption chamber 55 passes through the inside of the inner case 6B and, ultimately, the second adsorbent 3B in the axial direction of the inner case 6B.

[0068] When the second adsorbent 3B is held in the inner case 6B, the length L [mm] of the second adsorbent 3B is greater than the equivalent diameter D [mm] of the cross section of the second adsorbent 3B. More specifically, the length L of the second adsorbent 3B is the length L of the second adsorbent 3B along the direction of gas flow in the second adsorption chamber 55. More specifically, the equivalent diameter D of the cross section of the second adsorbent 3B is the equivalent diameter D of the cross section of the second adsorbent 3B that is perpendicular to the direction of gas flow in the second adsorption chamber 55.

[0069] The elastic member 7B has substantially the same configuration as the elastic member 7 described above. However, the elastic member 7B is disposed between the outer surface of the inner case 6B and the inner surface of the second adsorption chamber 55. Specifically, the elastic member 7B is disposed in the groove portion 62B in a state compressed in the radial direction. The elastic member 7B surrounds both the inner case 6B and the second adsorbent 3B in the circumferential direction of the inner case 6B. The elastic member 7B covers a portion of the inner case 6B in the axial direction of the inner case 6B from the radial outside of the inner case 6B. The elastic member 7B covers a portion of the second adsorbent 3B in the axial direction of the inner case 6B from the radial outside of the inner case 6B.

[0070] [3-2. Effects] According to the third embodiment described above in detail, the same effects as those (1a) to (1d) above can be obtained.

[0071] [4. Fourth Embodiment] [4-1.Configuration] The fourth embodiment has the same basic configuration as the third embodiment, and therefore differences will be described below. Note that the same reference numerals as those in the third embodiment indicate the same configuration, and reference is made to the preceding description.

[0072] 7, the evaporated fuel processing device 1C of the fourth embodiment includes an inner case 6C instead of the inner case 6B described above. The evaporated fuel processing device 1C also includes two elastic members 7B.

[0073] The inner case 6C has substantially the same configuration as the inner case 6B described above. However, the inner case 6C has two annular portions 64 and two grooves 62B. Each of the two annular portions 64 is provided with a groove 62B. An elastic member 7B is disposed in each groove 62B.

[0074] [4-2. Effects] According to the fourth embodiment described above in detail, the same effects as those of the third embodiment can be obtained, and the following additional effects can also be obtained.

[0075] In the evaporated fuel treatment device 1C of the fourth embodiment, two elastic members 7B are disposed between the outer surface of the inner case 6C and the inner surface of the second adsorption chamber 55. With this configuration, when the inner case 6C attempts to expand due to heat, a reaction force can be applied to the inner case 6C from each of the two elastic members 7B. This further suppresses the inner case 6C from expanding due to heat. This in turn further suppresses the formation of a gap between the inner surface of the inner case 6C and the outer surface of the second adsorbent 3B.

[0076] 5. Other Embodiments Although the embodiments of the present disclosure have been described above, it goes without saying that the present disclosure is not limited to the above-described embodiments and can take on various forms.

[0077] (5a) In the third adsorption chamber 56, at least a portion of the third adsorbent 4 is disposed inside the inner case 6. That is, the entire third adsorbent 4 may be disposed inside the inner case 6 as in the above embodiment, or only a portion of the third adsorbent 4 may be disposed inside the inner case 6. When only a portion of the third adsorbent 4 is disposed inside the inner case 6, the remaining portion of the third adsorbent 4 protrudes from the inner case 6. The same applies to the inner cases 6B and 6C in the above third and fourth embodiments.

[0078] (5b) In the above embodiment, the length L of the third adsorbent 4 is smaller than the equivalent diameter D of the cross section of the third adsorbent 4. However, the size of the equivalent diameter of the cross section of the third adsorbent relative to the length of the third adsorbent is not particularly limited. For example, the length of the third adsorbent may be the same as or larger than the equivalent diameter of the cross section of the third adsorbent 4. The same applies to the first adsorbent and the second adsorbent.

[0079] (5c) In the above embodiment, the third suction chamber 56 has the bottom support column 563 and the lid support column 564. However, the third suction chamber may not have at least one of the bottom support column and the lid support column, for example. Even if the third suction chamber does not have a support column, the position of the inner case 6 relative to the third suction chamber can be maintained by the elastic member 7.

[0080] (5d) In the above embodiments, the evaporated fuel treatment device 1, 1A, 1B, 1C includes the first adsorption chamber 54, the second adsorption chamber 55, and the third adsorption chamber 56. However, the number of adsorption chambers included in the evaporated fuel treatment device is not particularly limited, and may be, for example, one or more.

[0081] (5e) The function of one component in the above embodiments may be distributed among multiple components, or the functions of multiple components may be integrated into one component. Also, part of the configuration of the above embodiments may be omitted. Furthermore, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments. [Explanation of symbols]

[0082] 1, 1A, 1B, 1C...evaporative fuel treatment device, 2...first adsorbent, 3, 3B...second adsorbent, 4...third adsorbent, 5...outer case, 51...charge port, 52...purge port, 53...atmospheric port, 54...first adsorption chamber, 55...second adsorption chamber, 56...third adsorption chamber, 57...communicating passage, 6, 6A, 6B, 6C...inner case, 7, 7A, 7B...elastic member, F...flow path, Y1...compression force, Y2...reaction force.

Claims

1. An evaporated fuel treatment device, a mass adsorbent configured to adsorb fuel vapor; a cylindrical inner case configured to hold the adsorbent with at least a portion of the adsorbent disposed therein; an outer case that accommodates the adsorbent and the inner case; an elastic member disposed between the outer surface of the inner case and the inner surface of the outer case; Equipped with The elastic member surrounds both the inner case and the adsorbent in the circumferential direction of the inner case.

2. The fuel vapor treatment device according to claim 1, An evaporated fuel treatment device, wherein the length of the adsorbent along the gas flow direction is smaller than the equivalent diameter of a cross section of the adsorbent perpendicular to the gas flow direction.

3. 3. The fuel vapor treatment device according to claim 1, the outer case has an atmospheric port that is open to the atmosphere and an atmospheric-side adsorption chamber that is directly connected to the atmospheric port, The adsorbent and the elastic member are accommodated in the atmosphere-side adsorption chamber.

Images