Canister attachment structure

Abstract

This canister attachment structure is for attaching, to a framework member of a vehicle, a canister 10 including: a main chamber 11a that is connected to an engine and a fuel tank; and an auxiliary chamber 12a that is opened to the atmosphere and is connected to the main chamber 11a. The canister attachment structure is provided with: a main chamber housing 11 that has the main chamber 11a therein and is fixed to the framework member; a cylindrical auxiliary chamber housing 12 that has the auxiliary chamber 12a therein and is connected to the main chamber housing 11; and a C-shaped clamp 20 connecting the auxiliary chamber housing 12 to the framework member. The C-shaped clamp 20 includes a clamp part 21 that is curved along the outer circumferential surface of the auxiliary chamber housing 12, and an extension fastening part 22 extending from the clamp part 21 to a fastening portion of the framework member.

Description

Canister mounting structure

[0001] The present invention relates to a canister mounting structure.

[0002] Engine vehicles that use volatile fuel as a power source typically include a canister (charcoal canister, carbon canister, vapor collector) for collecting evaporated fuel generated in the fuel tank and supplying it to the engine. As an important safety component of the vehicle, such a canister is secured to a frame member such as the body frame via, for example, a metal bracket (see, for example, Patent Document 1). When installed in a passenger vehicle, the canister is often located near the engine or fuel tank, and can be secured to a side member, cross member, or dash panel that constitutes the frame member of the vehicle.

[0003] A typical canister has a main chamber connected to the fuel tank and engine, respectively, and an auxiliary chamber open to the atmosphere, with the two chambers communicating with each other. The main chamber contains a porous material such as activated carbon or zeolite to temporarily adsorb evaporated fuel flowing from the fuel tank through a tank port and supply the recovered fuel to the engine through a purge port as needed. The auxiliary chamber mediates airflow between the atmosphere and the main chamber, and the porous material, such as activated carbon or zeolite, prevents foreign matter other than air from entering or exiting the chamber.

[0004] Such a canister can have a main chamber and an auxiliary chamber formed by providing a partition wall inside a single housing, or can be configured as a so-called split canister, where the main chamber and the auxiliary chamber each have their own housing. For example, Patent Document 2 discloses a split canister in which a substantially rectangular parallelepiped main chamber and a substantially cylindrical auxiliary chamber communicate with each other via a communicating pipe.

[0005] Japanese Utility Model Publication No. 6-23735 Japanese Patent Application Laid-Open No. 2010-229838

[0006] However, when using a split canister as described above, it becomes necessary to fasten not only the main chamber housing but also the auxiliary chamber housing to the vehicle frame. In this case, if a conventional metal bracket is used as a fastening member, the auxiliary chamber housing and the metal bracket must be fastened with bolts and nuts, and the metal bracket must also be fastened to the vehicle frame. This increases the number of parts, which increases the effort required for installation and removal.

[0007] One possible solution to this problem is to mold the fastening mechanism for fastening the auxiliary housing to the vehicle frame as a single unit, but this method requires changing the design of the split canister housing for each vehicle model, for example, if the relative positions of the fastening points between the auxiliary housing and the frame differ depending on the vehicle model.

[0008] The present invention has been made in view of the above-mentioned problems, and its object is to provide a canister mounting structure that is easy to install and remove, and that allows a split canister to be shared even among different vehicle models.

[0009] In order to achieve the above-mentioned object, the canister mounting structure of the present invention is a canister mounting structure for mounting a canister including a main chamber connected to an engine and a fuel tank and an auxiliary chamber that is open to the atmosphere and communicates with the main chamber to a frame member of a vehicle, and comprises a main chamber housing having the main chamber therein and fixed to the frame member, a cylindrical auxiliary chamber housing having the auxiliary chamber therein and connected to the main chamber housing, and a C-type clamp connecting the auxiliary chamber housing to the frame member, the C-type clamp including a clamp portion curved along the outer peripheral surface of the auxiliary chamber housing, and an extended fastening portion extending from the clamp portion to a fastening point on the frame member.

[0010] According to the canister mounting structure of the present invention, even if the auxiliary housing is separate from the main housing, the auxiliary housing can be supported by a C-clamp fixed to the vehicle body without using bolts or nuts. Furthermore, even if the distance from the fastening point of the frame member to the auxiliary housing varies depending on the vehicle model, the auxiliary housing is fixed with a C-clamp having a corresponding extended fastening portion, so canisters of the same specifications can be used for different vehicle models. Therefore, the canister mounting structure of the present invention facilitates installation and removal, and allows the split canister to be shared across different vehicle models.

[0011] The canister mounting structure according to the present invention is a side view showing a schematic configuration thereof, a cross-sectional view showing a horizontal cross section of the canister mounting structure, and a side view showing a fixing structure according to a modified example of the auxiliary chamber housing and the C-type clamp.

[0012] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the contents described below, and can be implemented with any modifications within the scope that does not change the gist of the disclosure. Furthermore, all drawings used to explain the embodiments are schematic representations of components, and may be partially emphasized, enlarged, reduced, or omitted to facilitate understanding, and may not accurately represent the scale, shape, etc. of the components.

[0013] Fig. 1 is a side view showing a schematic configuration of a canister mounting structure according to the present invention, and Fig. 2 is a cross-sectional view showing a horizontal section of the canister mounting structure, more specifically, a schematic view of the A-A section of Fig. 1.

[0014] The canister mounting structure is a configuration for fixing a canister 10, which collects evaporated fuel generated in a fuel tank in a vehicle powered by volatile fuel, to the vehicle body using a C-clamp 20, which will be described later. In each drawing, the X and Y directions, which are orthogonal to each other, indicate the horizontal direction, and the Z direction indicates the vertical direction.

[0015] The canister 10 has, as its main exterior components, a main chamber housing 11, an auxiliary chamber housing 12, and a connecting pipe 13, all of which are made of synthetic resin in this embodiment. However, the material of the canister 10 is not limited to synthetic resin, and it may be made of other materials such as metal.

[0016] The main chamber housing 11 of this embodiment is a generally rectangular parallelepiped housing having a main chamber 11a therein, which contains a porous material such as activated carbon or zeolite. The main chamber housing 11 also has a tank port 11b, which connects the main chamber 11a to a fuel tank (not shown), and a purge port 11c, which connects the main chamber 11a to an engine (not shown), at its bottom. The main chamber housing 11 also has a main chamber-side fixing portion 11d that protrudes from its side, and is fixed to a vehicle frame member with bolts via fastening holes FH formed in the main chamber-side fixing portion 11d.

[0017] The auxiliary chamber housing 12 is a generally cylindrical casing having an auxiliary chamber 12a therein, which contains a porous material such as activated carbon or zeolite. The auxiliary chamber housing 12 also has a vent port 12b at its bottom, which opens the auxiliary chamber 12a to the atmosphere. Furthermore, as will be described in detail later, the auxiliary chamber housing 12 has a positioning protrusion 12c formed on its outer periphery, and is fixed to a vehicle frame member with a C-clamp 20.

[0018] The canister 10 can be placed near the engine or fuel tank, and can be stably supported on the vehicle body by being fixed to a frame member such as a side member, cross member, or dash panel that constitutes the body.

[0019] The communication pipe 13 has both ends connected to the upper side surfaces of the main chamber housing 11 and the auxiliary chamber housing 12, respectively, and defines a gas flow path therein that connects the main chamber 11a and the auxiliary chamber 12a.

[0020] With the above-described configuration, the canister 10 adsorbs evaporated fuel that flows from the vehicle's fuel tank through the tank port 11b using the porous material in the main chamber 11a. At this time, the gas that passes through the main chamber 11a is supplied to the auxiliary chamber 12a via the connecting pipe 13, and after the remaining fuel components are adsorbed by the porous material in the auxiliary chamber 12a, the gas is released as clean air into the atmosphere through the vent port 12b.

[0021] In addition, when the engine is running, the canister 10 draws in air through the vent port 12b, purges the evaporated fuel adsorbed by each porous body through the auxiliary chamber 12a, the connecting pipe 13, and the main chamber 11a, and supplies the evaporated fuel to the engine through the purge port 11c.

[0022] Here, the canister 10 of this embodiment is a so-called split canister in which the main chamber housing 11 and the auxiliary chamber housing 12 are separate bodies, and therefore it is necessary to fix not only the main chamber housing 11 but also the auxiliary chamber housing 12 to the vehicle frame members. In the canister mounting structure according to the present invention, the auxiliary chamber housing 12 is fixed via a C-clamp 20.

[0023] More specifically, the C-clamp 20 is made of, for example, synthetic resin and is a single component that is continuously and integrally formed with a clamp portion 21 that curves along the outer circumferential surface of the cylindrical auxiliary housing 12 and an extended fastening portion 22 that extends from the clamp portion 21 to a fastening point on the frame member. The C-clamp 20 is fixed to the frame member of the vehicle with a bolt through a fastening hole FH formed in the extended fastening portion 22.

[0024] The C-clamp 20 is attached by sliding the clamp portion 21 while slightly widening it from below the auxiliary housing 12 in the vertical direction. Then, when the clamp portion 21 reaches a predetermined position on the outer circumferential surface of the auxiliary housing 12, the C-clamp 20 fastens the extended fastening portion 22 to a frame member of the vehicle, thereby fixing the auxiliary housing 12 to the vehicle body.

[0025] In the C-clamp 20 of this embodiment, the leading end surface of the clamp portion 21 is formed as an arc-shaped recess when viewed from the side. Meanwhile, the auxiliary chamber housing 12 is formed with a positioning protrusion 12c at the position of the leading end surface of the clamp portion 21, and is formed as an arc-shaped protrusion relative to the leading end surface of the clamp portion 21. Therefore, the positioning protrusion 12c engages with the leading end surface of the clamp portion 21 to restrict relative displacement of the auxiliary chamber housing 12, so that the auxiliary chamber housing 12 is stably supported by the vehicle body via the C-clamp 20 against vibrations and shocks while the vehicle is running, as well as against purging operations in the auxiliary chamber 12a.

[0026] The tip surface of the clamp portion 21 and the positioning protrusion 12c of the auxiliary housing 12 are not limited to being arc-shaped, and may have other shapes as long as they are engageable to restrict relative displacement between them. Furthermore, the positioning protrusion 12c has a shape that extends along the longitudinal direction of the auxiliary housing 12 (Z direction in the figure), and therefore functions as a reinforcing member that improves the rigidity of the auxiliary housing 12.

[0027] Furthermore, as shown in FIG. 2, the C-type clamp 20 is provided with an elastic sheet 23 on the inner peripheral surface of the clamp portion 21, which reduces vibrations transmitted from the frame member to the auxiliary chamber housing 12 while the vehicle is running, and also suppresses the transmission of pulsating noise caused by the purging operation in the auxiliary chamber 12a to the frame member.

[0028] The shape of the frame members of the vehicle in which the canister 10 is mounted and the arrangement of the auxiliary chamber housing 12 relative to the frame members may differ depending on the vehicle model. In this case, the C-type clamp 20 is formed with variations in the length and shape of the extended fastening portion 22 that connect the position of the auxiliary chamber housing 12 to a fastening point (not shown) on the frame member of the vehicle, depending on the vehicle model.

[0029] Therefore, even if the relative position between the auxiliary chamber housing 12 and the fastening point of the skeletal member differs depending on the vehicle model, by selecting a C-type clamp 20 appropriate for the vehicle model, there is no need to change the housing design of the canister 10 for each vehicle model.

[0030] Furthermore, unlike conventional metal brackets that use bolts and nuts to secure the auxiliary chamber housing 12 to the C-clamp 20, the number of parts does not increase, and the effort required for removal and attachment does not increase.

[0031] As described above, with the canister mounting structure according to the present invention, even if the canister 10 has the auxiliary housing 12 separated from the main housing 11, the auxiliary housing 12 can be supported by the C-clamp 20 fixed to the vehicle body without using bolts or nuts. Furthermore, even if the distance from the fastening point of the frame member to the auxiliary housing 12 varies depending on the vehicle model, the auxiliary housing 12 is fixed by the C-clamp 20 having the corresponding extended fastening portion 22, so that the same specifications can be used for different vehicle models. Therefore, with the canister mounting structure according to the present invention, installation and removal is easy, and split canisters can be shared even for different vehicle models.

[0032] Although the description of the embodiment is now complete, the canister mounting structure is not limited to the above embodiment. For example, in the above embodiment, the tip surface of the C-clamp 20 engages with the positioning protrusion 12c of the auxiliary housing 12, but the engagement between the two may be changed as shown in Figure 3.

[0033] More specifically, Fig. 3 is a side view showing a modified fixing structure between the auxiliary housing 12 and the C-clamp 20. The auxiliary housing 12 has a modified positioning protrusion 12d that has arc-shaped protrusions on both circumferential sides of its outer circumferential surface. The C-clamp 20 also has arc-shaped recesses formed not only on the tip surface of the clamp portion 21 but also on the modified extended fastening portion 22v. Therefore, with this modified fixing structure, the C-clamp 20 engages with the auxiliary housing 12 so as to sandwich the extended fastening portion 22v, thereby more stably supporting the auxiliary housing 12.

[0034] In addition, in the above embodiment, an example was given of a configuration in which the main chamber housing 11 and the auxiliary chamber housing 12 are connected via a communicating pipe 13, but the main chamber 11a and the auxiliary chamber 12a may also be connected within a single canister case without using the communicating pipe 13.

[0035] REFERENCE SIGNS LIST 10 Canister 11 Main chamber housing 11a Main chamber 11b Tank port 11c Purge port 11d Main chamber side fixing portion 12 Auxiliary chamber housing 12a Auxiliary chamber 12b Vent port 12c Positioning protrusion 13 Connecting pipe 20 C-type clamp 21 Clamp portion 22 Extended fastening portion FH Fastening hole

Claims

1. A canister mounting structure for mounting a canister, which includes a main chamber connected to an engine and a fuel tank, and an auxiliary chamber that is open to the atmosphere and communicates with the main chamber, to a vehicle frame member, comprising: a main chamber housing having the main chamber therein and fixed to the frame member; a cylindrical auxiliary chamber housing having the auxiliary chamber therein and connected to the main chamber housing; and a C-clamp that connects the auxiliary chamber housing to the frame member, wherein the C-clamp includes a clamp portion that curves along the outer circumferential surface of the auxiliary chamber housing, and an extended fastening portion that extends from the clamp portion to a fastening point on the frame member.

2. The canister mounting structure according to claim 1, wherein the C-clamp has an elastic sheet on the inner peripheral surface of the clamping portion.

3. A canister mounting structure as set forth in claim 1 or 2, wherein the auxiliary chamber housing has a positioning protrusion on a part of the outer circumferential surface, and the tip surface of the clamping portion and the positioning protrusion of the auxiliary chamber housing engage to restrict relative displacement.

4. A canister mounting structure according to claim 3, wherein the positioning protrusion extends along the longitudinal direction of the auxiliary chamber housing.

5. A canister mounting structure according to claim 3, wherein the positioning projections engage with the C-clamps on both circumferential sides of the auxiliary chamber housing.

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