canister

Abstract

To provide a canister capable of reducing a clearance of an adsorption member constituted by an adsorption sheet.SOLUTION: One embodiment of this disclosure is a canister that adsorbs and desorbs evaporation fuel generated in a fuel tank of a vehicle. The canister includes: a charge port for taking in the evaporation fuel; a purge port for discharging the evaporation fuel; an atmospheric port opened in the atmosphere; a first adsorption chamber and a second adsorption chamber that are connected to the charge port and the purge port directly or via another chamber; a first adsorption member accommodated in the first adsorption chamber; and a second adsorption member accommodated in the second adsorption chamber. The second adsorption member includes: a core material; and an adsorption sheet that is wound around the core material and has a property of adsorbing the evaporation fuel.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a canister. [Background technology]

[0002] A canister is attached to a vehicle's fuel tank to prevent evaporated fuel from being released into the atmosphere. The canister adsorbs the evaporated fuel onto an adsorption member, draws in air to desorb the fuel from the adsorption member, and then supplies the fuel to the engine for purging.

[0003] As an adsorption member for such a canister, a stack of a plurality of adsorption sheets is known (see Patent Document 1). Such a stack can also be obtained by rolling up the adsorption sheets. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7250145 Summary of the Invention [Problem to be solved by the invention]

[0005] When the adsorption member is constructed by rolling the adsorption sheet as described above, gaps may occur between adjacent layers, which may allow the evaporated fuel to pass through without being adsorbed by the adsorption sheet.

[0006] An object of one aspect of the present disclosure is to provide a canister that can reduce gaps in an adsorption member that is made up of an adsorption sheet. [Means for solving the problem]

[0007] One aspect of the present disclosure is a canister for adsorbing and desorbing evaporated fuel generated in a vehicle fuel tank. The canister includes a charge port for taking in evaporated fuel, a purge port for discharging evaporated fuel, an air port open to the atmosphere, a first adsorption chamber and a second adsorption chamber connected to the charge port and the purge port directly or via another chamber, a first adsorption member housed in the first adsorption chamber, and a second adsorption member housed in the second adsorption chamber. The first adsorption member includes a core material and an adsorption sheet wound around the core material and capable of adsorbing evaporated fuel.

[0008] With this configuration, the adsorbent sheet is wound around the core material, which increases the adhesion between adjacent layers of the adsorbent sheet, thereby reducing the gaps in the first adsorbent member and preventing the passage of evaporated fuel.

[0009] In one aspect of the present disclosure, the core material may be non-air permeable, which can prevent the vaporized fuel from passing through the core material.

[0010] In one aspect of the present disclosure, the evaporated fuel may flow in the first adsorption chamber along the axial direction of the wick. With this configuration, the wick located at the center of the first adsorption member prevents the gas flowing through the first adsorption chamber from being concentrated toward the center of the first adsorption member, thereby dispersing the flow of evaporated fuel throughout the first adsorption chamber.

[0011] In one aspect of the present disclosure, the cross-sectional shape of the outer peripheral surface of the core material, taken perpendicular to the axial direction of the core material, may be similar to the cross-sectional shape of the inner peripheral surface of the first adsorption chamber, taken perpendicular to the axial direction of the core material. This configuration allows the first adsorption member to be formed to match the shape of the first adsorption chamber. This increases the design freedom of the first adsorption chamber.

[0012] In one aspect of the present disclosure, the core material may have a holding mechanism for holding a portion of the suction sheet, which prevents the suction sheet from shifting when the suction sheet is rolled up, thereby improving the adhesion between adjacent layers of the suction sheet.

[0013] In one aspect of the present disclosure, the adsorbent sheet may be formed of fibers capable of adsorbing evaporated fuel. The first adsorbent may further include particles having adsorbent properties for evaporated fuel, dispersed on or within the adsorbent sheet. With this configuration, the combination of the adsorption capacity of the adsorbent sheet and the adsorption capacity of the particles allows the first adsorbent to exhibit an adsorption effect for a wide range of evaporated fuel concentrations.

[0014] In one aspect of the present disclosure, the first adsorption chamber may be directly connected to the atmospheric port, which reduces the amount of evaporated fuel leaking from the atmospheric port. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram of a canister according to an embodiment. [Figure 2] 2A is a schematic perspective view of a first adsorption member in the canister of FIG. 1, and FIG. 2B is a schematic plan view of the first adsorption member of FIG. 2A. [Figure 3] FIG. 3A is a schematic plan view of a first suction member in an embodiment different from that in FIG. 2A, and FIG. 3B is a schematic perspective view of the first suction member in FIG. 3A. [Figure 4] 4A and 4B are schematic perspective views of the core material of the first suction member of FIG. 2A, and FIGS. 4C and 4D are schematic perspective views of the core material in an embodiment different from that of FIGS. 4A and 4B. [Figure 5] 5A and 5B are schematic perspective views of a core material in an embodiment different from that in FIGS. 4A and 4B, and FIGS. 5C and 5D are schematic perspective views of a core material in an embodiment different from that in FIGS. 4A and 4B. [Figure 6] FIG. 6 is a schematic development view of the suction sheet of the first suction member of FIG. 2A. [Figure 7] FIG. 7 is a schematic perspective view of a first adsorption member in an embodiment different from that in FIG. 2A. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments to which the present disclosure is applied will be described with reference to the drawings. [1. First embodiment] [1-1.Configuration] A canister 1 shown in FIG. 1 is an evaporated fuel treatment device that adsorbs and desorbs evaporated fuel generated in a fuel tank of a vehicle.

[0017] The canister 1 includes a charge port 2A, a purge port 2B, an atmospheric port 2C, a first adsorption chamber 3, a second adsorption chamber 4, a third adsorption chamber 5, a first adsorption member 7, a second adsorption member 8, and a third adsorption member 9.

[0018] <Charge port> The charge port 2A is connected to a fuel tank of the vehicle by a pipe and is configured to take in evaporated fuel generated in the fuel tank into the canister 1.

[0019] <Purge port> The purge port 2B is connected to an intake pipe of a vehicle engine via a purge valve, and is configured to discharge evaporated fuel from the canister 1 and supply it to the engine.

[0020] <Atmospheric port> The atmospheric port 2C is open to the atmosphere. The atmospheric port 2C releases gas from which evaporated fuel has been removed into the atmosphere. The atmospheric port 2C also takes in outside air (i.e., purge air) to desorb (i.e., purge) the evaporated fuel adsorbed by the canister 1.

[0021] <1st adsorption chamber> The first adsorption chamber 3 houses a first adsorption member 7. The atmospheric port 2C is directly connected to the first adsorption chamber 3 without passing through another adsorption chamber. The first adsorption chamber 3 communicates with the atmospheric port 2C and the third adsorption chamber 5. The first adsorption chamber 3 discharges the gas that has adsorbed the evaporated fuel from the atmospheric port 2C.

[0022] <Second adsorption chamber> The second adsorption chamber 4 houses a second adsorption member 8. The charge port 2A and the purge port 2B are directly connected to the second adsorption chamber 4 without going through another adsorption chamber. The second adsorption chamber 4 is in communication with the charge port 2A, the purge port 2B, and the third adsorption chamber 5. The second adsorption chamber 4 adsorbs evaporated fuel taken in through the charge port 2A. The second adsorption chamber 4 also discharges the adsorbed evaporated fuel from the purge port 2B.

[0023] <3rd adsorption chamber> The third adsorption chamber 5 houses a third adsorption member 9. The third adsorption chamber 5 is disposed between the first adsorption chamber 3 and the second adsorption chamber 4 in the flow path of the evaporated fuel.

[0024] The evaporated fuel taken in from the charge port 2A is adsorbed by the second adsorption member 8 in the second adsorption chamber 4. The evaporated fuel that cannot be adsorbed in the second adsorption chamber 4 moves to the third adsorption chamber 5, where it is adsorbed by the third adsorption member 9.

[0025] Furthermore, the evaporated fuel that cannot be adsorbed in the third adsorption chamber 5 moves to the first adsorption chamber 3, where it is adsorbed by the first adsorption member 7. The gas with the adsorbed evaporated fuel is released from the atmospheric port 2C.

[0026] Furthermore, by drawing air in through the atmospheric port 2C, the evaporated fuel that has been adsorbed by the adsorption members in the first adsorption chamber 3, the second adsorption chamber 4, and the third adsorption chamber 5 is discharged to the engine through the purge port 2B, and as a result, air containing evaporated fuel is supplied to the engine.

[0027] <First suction member> The first adsorption member 7 is housed in the first adsorption chamber 3. As shown in FIG.

[0028] <Core material> The core material 71 is a rod-shaped member that is air-impermeable. The core material 71 is made of a material that is substantially air-impermeable, and has a structure that does not allow gas to pass through (i.e., does not have any communicating holes or spaces).

[0029] The first adsorption member 7 is disposed so that the axial direction of the core material 71 is parallel to the flow direction G of the evaporated fuel in the first adsorption chamber 3. That is, in the first adsorption chamber 3, the evaporated fuel flows along the axial direction of the core material 71.

[0030] 2B, the cross-sectional shape (hereinafter referred to as the "first shape") S1 of the outer peripheral surface of the core material 71, which is perpendicular to the axial direction of the core material 71, is similar to the cross-sectional shape (hereinafter referred to as the "second shape") S2 of the inner peripheral surface of the first adsorption chamber 3, which is perpendicular to the axial direction of the core material 71. For example, if the second shape S2 of the first adsorption chamber 3 is circular (i.e., if the internal space of the first adsorption chamber 3 is cylindrical), the first shape S1 of the core material 71 is also circular (i.e., the core material 71 is cylindrical).

[0031] Also, for example, when the second shape S2 of the first adsorption chamber 3 is rectangular (i.e., when the internal space of the first adsorption chamber 3 is a rectangular prism) as shown in FIG. 3A, the first shape S1 of the core material 71 is also rectangular (i.e., the core material 71 is a rectangular prism as shown in FIG. 3B).

[0032] 4A, core 71 has a holding mechanism 71A that holds a portion of suction sheet 72. Holding mechanism 71A has a base 71B and a pressing portion 71C. Base 71B and pressing portion 71C each have a holding surface 71D on which suction sheet 72 is placed.

[0033] The pressing portion 71C is configured to be movable relative to the base portion 71B. The pressing portion 71C is displaceable between a release position (see FIG. 4A) away from the base portion 71B and a holding position (see FIG. 4B) where the pressing portion 71C, together with the base portion 71B, clamps a part (for example, an end portion) of the suction sheet 72. Specifically, the pressing portion 71C is configured such that a first end portion 711 in the axial direction of the core material 71 is connected to the base portion 71B and is swingable around this first end portion 711.

[0034] The contact surfaces of the base 71B and the pressing portion 71C with the suction sheet 72 (i.e., the holding surfaces 71D) are provided with uneven shapes 71E that suppress slippage of the suction sheet 72. Examples of the uneven shapes 71E include ridges extending in the axial direction of the core material 71.

[0035] 4C and 4D or 5A and 5B, the holding mechanism 71A may have a snap-fit ​​structure 71F that fixes the pressing portion 71C in the holding position to the base portion 71B. Furthermore, as shown in FIGS. 5C and 5D, the pressing portion 71C may be configured such that a second end 712 opposite to the first end 711 connected to the base portion 71B is press-fit into the base portion 71B.

[0036] <Adsorption sheet> 2A, the adsorption sheet 72 is wound around the core material 71. The adsorption sheet 72 has the ability to adsorb evaporated fuel. That is, the adsorption sheet 72 adsorbs evaporated fuel and butane supplied to the canister 1 together with air and the like. The adsorption sheet 72 also desorbs the evaporated fuel and butane when external air is introduced.

[0037] Specifically, the adsorption sheet 72 is made of fibers that have the ability to adsorb fuel vapor. For example, woven, knitted, or nonwoven carbon fiber fabrics can be suitably used as the adsorption sheet 72.

[0038] 6, granules 73 are dispersed on or inside the adsorption sheet 72. The granules 73 have the ability to adsorb evaporated fuel. That is, the first adsorption member 7 has granules 73 dispersed on or inside the adsorption sheet 72, which have the ability to adsorb evaporated fuel.

[0039] Examples of the granules 73 include activated carbon and zeolite. The granules 73 are held by the adsorbent sheet 72 by getting into the gaps between the fibers that make up the adsorbent sheet 72 (i.e., by becoming entangled in the fibers). The adsorbent sheet 72 is wrapped around the core material 71 with the granules 73 disposed thereon. The granules 73 are disposed on the adsorbent sheet 72 by, for example, scattering or coating.

[0040] The adsorption performance of the adsorption sheet 72 is different from that of the granules 73. In addition, a plurality of types of granules 73 (i.e., granules 73 having different adsorption capacities and / or desorption capacities) may be arranged on the adsorption sheet 72. Furthermore, the adsorption sheet 72 may be provided with a first region in which the granules 73 are arranged and a second region in which the granules 73 are not arranged.

[0041] The suction sheet 72 is wound around the core material 71 to form multiple cylindrical layers. That is, the wound suction sheet 72 has multiple layers stacked in the radial direction. The outer circumferential surface of the inner layer of the suction sheet 72 is in contact with the inner circumferential surface of the outer layer. Therefore, within the wound suction sheet 72, there is essentially no path for air to pass in the axial direction of the core material 71.

[0042] <Second suction member and third suction member> The second adsorption member 8 and the third adsorption member 9 respectively adsorb the evaporated fuel and butane supplied to the canister 1 together with air, etc. Furthermore, the second adsorption member 8 and the third adsorption member 9 desorb the evaporated fuel and butane by introducing external air.

[0043] The second adsorption member 8 and the third adsorption member 9 can be made of materials such as activated carbon and zeolite. Examples of activated carbon include aggregates of granular adsorbents, activated carbon formed into a honeycomb shape, and fibrous activated carbon formed into a sheet, rectangular parallelepiped, cylindrical, or prismatic shape. The second adsorption member 8 and the third adsorption member 9 may be made of the same type of adsorbent, or different types of adsorbents. Furthermore, the second adsorption member 8 and the third adsorption member 9 may have a core material and an adsorption sheet wound around the core material, similar to the first adsorption member 7.

[0044] [1-2.Effects] According to the embodiment described above in detail, the following effects can be obtained. (1a) By winding the adsorbent sheet 72 around the core material 71, it is possible to improve the adhesion between adjacent layers of the adsorbent sheet 72. This reduces the gaps in the first adsorbent member 7, thereby suppressing the passage of evaporated fuel.

[0045] (1b) Since the core material 71 is non-permeable, the passage of evaporated fuel through the core material 71 can be suppressed.

[0046] (1c) Since the evaporated fuel flows along the axial direction of the core material 71, the presence of the core material 71 located at the center of the first adsorption member 7 prevents the gas flowing through the first adsorption chamber 3 from being biased toward the center of the first adsorption member 7. Therefore, the flow of evaporated fuel can be dispersed throughout the entire first adsorption chamber 3.

[0047] (1d) Since the first shape S1 of the core material 71 is similar to the second shape S2 of the first adsorption chamber 3, the first adsorption member 7 can be formed to match the shape of the first adsorption chamber 3. This improves the degree of freedom in designing the first adsorption chamber 3.

[0048] (1e) Since the core material 71 has the holding mechanism 71A, the shifting of the suction sheet 72 when the suction sheet 72 is rolled up is suppressed, and therefore the adhesion between adjacent layers of the suction sheet 72 can be improved.

[0049] (1f) Since the first adsorption member 7 has granules 73 dispersedly arranged on the adsorption sheet 72, the combination of the adsorption capacity of the adsorption sheet 72 and the adsorption capacity of the granules 73 enables the first adsorption member 7 to have an adsorption effect on a wide range of concentrations of evaporated fuel.

[0050] (1g) By accommodating the first adsorption member 7 in the first adsorption chamber 3 connected to the atmospheric port 2C, the amount of evaporated fuel leaking from the atmospheric port 2C can be reduced.

[0051] 2. 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.

[0052] (2a) In the canister of the above embodiment, the evaporated fuel does not necessarily flow along the axial direction of the core material in the first adsorption chamber. For example, as shown in Fig. 7, the first adsorption member 7 may be arranged so that the axial direction of the core material 71 intersects with the flow direction G of the evaporated fuel in the first adsorption chamber. In this case, the core material 71 may be hollow (i.e., cylindrical).

[0053] (2b) In the canister of the above embodiment, the core does not necessarily have to have a holding mechanism for holding the suction sheet. The suction sheet may be fixed to the core by a fixing means such as an adhesive. The core may be inserted into the wound suction sheet after the wound suction sheet is placed in the suction chamber.

[0054] (2c) In the canister of the above embodiment, the first adsorption member does not necessarily have to have granules. Also, the material of the adsorption sheet is not limited to fiber, as long as it has breathability and adsorption properties.

[0055] (2d) In the canister of the above embodiment, the first adsorption member does not necessarily have to be housed in an adsorption chamber connected to the atmospheric port. For example, the first adsorption member may be housed in an adsorption chamber connected to the charge port and the purge port.

[0056] (2e) 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. All aspects included in the technical idea identified by the wording of the claims are embodiments of the present disclosure. [Explanation of symbols]

[0057] 1...Canister, 2A...Charge port, 2B...Purge port, 2C...Atmospheric port, 3...first adsorption chamber, 4...second adsorption chamber, 5...third adsorption chamber, 7...first adsorption member, 8... second suction member, 9... third suction member, 71... core material, 71A... holding mechanism, 71B...base portion, 71C...pressing portion, 71D...holding surface, 71E...uneven shape, 71F...snap fit structure, 72...adsorption sheet, 73...granules, 711...first end portion, 712...Second end.

Claims

1. A canister that adsorbs and desorbs evaporated fuel generated in a fuel tank of a vehicle, a charge port that takes in the evaporated fuel; a purge port for discharging the evaporated fuel; an atmospheric port open to the atmosphere; a first adsorption chamber and a second adsorption chamber connected to the charge port and the purge port directly or via another chamber; a first adsorption member housed in the first adsorption chamber; a second adsorption member housed in the second adsorption chamber; Equipped with The first adsorption member is A core material and an adsorption sheet wound around the core material and having adsorption properties for the evaporated fuel; and the adsorption sheet is formed of fibers having adsorption properties for the evaporated fuel, the first adsorption member further includes particles having adsorption properties for the evaporated fuel and dispersed on the surface or inside of the adsorption sheet, The core material is configured to be substantially impermeable to gas; The first adsorption member is disposed in the first adsorption chamber so that the core extends along the direction of the fuel vapor flow.

2. A canister according to claim 1, A canister, wherein the cross-sectional shape of the outer peripheral surface of the core material, taken perpendicular to the axial direction of the core material, is similar to the cross-sectional shape of the inner peripheral surface of the first adsorption chamber, taken perpendicular to the axial direction of the core material.

3. 3. The canister according to claim 1 or 2, The canister has a core member having a holding mechanism for holding a portion of the suction sheet.

4. 3. The canister according to claim 1 or 2, The first adsorption chamber is directly connected to the atmospheric port.

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