JPS603025Y2 - Canister device for adsorption of evaporated fuel in motorcycles - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention (1) Industrial Application Field The present invention relates to a canister device for temporarily adsorbing evaporated fuel from a fuel tank or the like in a motorcycle.

(2) Conventional technology Traditionally, when a vehicle is running an engine, a fuel tank,
The fuel that evaporates from the float chamber of the carburetor is adsorbed into a canister that contains an adsorbent for evaporated fuel such as activated carbon, and the adsorbed fuel is returned to the engine intake system to release unburned harmful components into the atmosphere. For example, a means for preventing the release of unburned harmful components into the atmosphere is disclosed in Utility Model Application Publication No. 52
This method has already been disclosed in Japanese Utility Model Publication No.-83154 and Japanese Utility Model Application Publication No. 55-76785.

(3) Problems to be solved by the invention However, in the conventional canister device for adsorbing evaporated fuel in motorcycles, a purge air inlet is simply opened in the canister, or purge air is introduced into the canister through an air chamber, pipe, etc. As a result, droplets, dust, etc. enter the canister through the purge air inlet, impeding the function of the canister, increasing the number of parts, complicating the structure, increasing costs, and making it difficult to install in a narrow space. There is a problem in that it makes the installation work of the canister difficult.

This invention was developed in view of the above circumstances, and
To provide a canister device for adsorbing evaporated fuel in a motorcycle, which has a simple structure and allows Persure to be sucked into the canister without infiltration of dust or the like.

B. Structure of the invention (1) Means for solving the problems According to the invention, the purge air inlet opened in the canister is communicated with the central frame pipe extending in the vertical direction and forming a part of the vehicle body frame. Then, an atmospheric air suction port is opened at the upper part of the central frame pipe, and purge air is introduced into the canister from the atmospheric suction port through the central frame pipe and the purge air inlet.

(2) Effect According to the above configuration, purge air that does not contain splashes, dust, etc. is sucked into the canister.

(3) Example Hereinafter, an example of the present invention will be explained with reference to the drawings. Figures 1 and 2 show a part of a motorcycle, and the engine body 1 is located in the center of the body frame F. It will be installed.

At the rear of the engine body 1, a rear fork 4 is pivotally supported 5 at the lower part of the vehicle body frame F so as to be able to swing up and down, and the rear wheel 2 is rotatably supported 6 at the rear end of the rear fork 4.
Furthermore, a buffer mechanism 7 is connected between the rear end of the rear fork 4 and the rear upper end of the vehicle body frame F.

A seat 3 is mounted on the upper part of the vehicle body frame F, spanning the rear part of the engine body 1 and the rear wheels 2.
, a space C having a substantially inverted triangular shape when viewed from the side is formed between the rear wheel 2, the seat 3, and the rear fork 4.

In the space C, the upper end of a battery box 8 containing a battery B is suspended from the upper part of the vehicle body frame F via an elastic member 9, and a mounting piece 19 is attached to the lower part of the battery box 8. A cylindrical canister CA for adsorbing evaporated fuel is integrally suspended horizontally with respect to the traveling direction of the motorcycle, and this canister CA has its front end connected to the engine body 1 and its rear end connected to It is covered by a rear wheel 2, a seat 3 above it, and a rear fork 4 below it.

In FIG. 1, 10 is a fuel tank fixedly installed on the body frame F in front of the seat 3, 11 and 12 are a carburetor and air cleaner connected to the intake system of the engine body 1, and 13 is a battery box. A tool box 8 is supported by the vehicle body frame F at the rear, and 14 is a blow-by gas capture tank supported by the vehicle body frame F at the rear between the battery box 8 and the canister CA.

Next, the specific structure of the canister CA will be explained with reference to FIGS. 3 and 4. The canister casing 1
5 has end plates 17 at both ends of the hollow cylindrical casing main body 16.
, 18, and a mounting piece 19 for attaching to the vehicle body frame F is welded to the upper part of the negative side thereof.

One end inside the canister casing 45 (left end in Figure 3)
includes a first holding member 20 with a filter 22 attached to its inner surface.
is fitted to the other end (right end in FIG. 3), and a second holding member 21, which also has a filter 23 attached to its inner surface, is fitted so as to be slidable back and forth. Second holding member 2
0.21, the inside of the hollow cylindrical canister casing 15 has a large-capacity adsorption chamber a in the center thereof, and a first adsorption chamber a on the left and right sides thereof. A second air chamber b□, b2 is formed,
Those chambers a, b□ and b2 are connected to the filter 22.
They communicate with each other via 23.

A compression spring 24 is compressed in the second air chamber b2, and the elastic force of the compression spring 24 urges the second holding plate 21 to move inward within the casing 15.

The adsorption chamber a is filled with an evaporated fuel adsorbent A such as activated carbon.

A conduit 25 is provided in the center of the canister casing 15.
is inserted, and this conduit 25 is connected to the first. second holding plate 20,
21 and the center of the end plate 17, its inner end is opened into the second air chamber b2, and its outer end is bent into an elbow shape and opened to the outside of the canister casing 15. The open end 25' is connected to a fuel tank 10 of the internal combustion engine, a vaporized fuel generation source such as a float chamber of the carburetor 11, and an intake system of the engine.

On one side of the canister CA, a central frame pipe p forming a part of the vehicle body frame F extends vertically so as to intersect with the canister CA. A purge air inlet 26 opened in the end plate 17 is communicated with the lower part of the central frame pipe p via a communication pipe 28.

An atmospheric air suction port 27 is opened at the upper part of the central frame pipe p, and this atmospheric air suction port 27 is communicated with the air cleaner 12.

Further, a drain port 29 is opened at the lower part of the central frame pipe p.

Next, the operation of one embodiment of the present invention will be explained. When the internal combustion engine is mainly stopped, the evaporated fuel evaporated from the evaporated fuel generation source such as the fuel tank 10 or the flow chamber of the carburetor 11 passes through the conduit 25 to the second air. The fuel flows into the chamber b2, passes through the filter 23, and flows into the adsorption chamber a, where it is temporarily adsorbed by the evaporated fuel adsorbent A such as activated carbon.

When the engine is started, the intake negative pressure in the intake system is transferred to the conduit 2.
The air is partially purified by the air cleaner 12, and then flows into the canister CA through the central pipe p1 and the communication pipe 28, where it is adsorbed by the evaporated fuel adsorbent A. The fuel is separated from the adsorbent A, and the separated fuel is absorbed into the engine body 1 together with air by the intake negative pressure through the filter 23, the second air chamber b2, and the conduit 25, and is combusted.

Further, the fuel and moisture adsorbed by the evaporated fuel adsorbent A and turned into droplets are led to the central pipe p through the purge air inlet 26 and the communication pipe 28, and are discharged to the outside from the drain port 29.

In the above embodiment, the first air chamber b1 is opened to the atmosphere through the atmosphere communication port 26 opened in the end plate 17, but the first air chamber b1 is omitted. The end of the adsorption chamber a on the side of the chamber b1 may be opened directly to the atmosphere, and in the embodiment described above, a single conduit 25 connects the canister CA, the evaporative fuel generation source such as the fuel tank 10, and the engine. I made it communicate with the intake system, but
The canister CA may be communicated with the vaporized fuel generation source and the engine intake system through separate conduits.

Effects of the C0 Design As described above, according to the present invention, the engine is surrounded by the engine body 1, the rear wheel 2, the seat 3, and the rear fork 4, which are arranged at the center, rear, upper, and lower parts of the vehicle body frame F, respectively. A vaporized fuel adsorption canister CA supported by the vehicle body frame F is disposed in the space C, and a purge air inlet 26 opened in the canister CA is connected to the canister CA, which forms a part of the vehicle body frame F, in the vertical direction. An atmosphere suction port 27 is opened at the upper part of the central frame pipe p, and purge air is introduced into the canister C from the atmosphere suction port 27 through the central frame pipe p1 and the purge air introduction port 26. Therefore, the atmosphere suction port 27 is located at the top of the central frame pipe p, that is, at the top of the motorcycle.
There is no fear that droplets, dust, etc. thrown up by the running of the motorcycle will enter the canister C, and there is no fear that the function of the canister CA will be inhibited.

Furthermore, since the central frame pipe p can also be used as a purge air introduction path, there is no need to separately install the passage, which reduces the number of parts, simplifies the structure, and reduces costs, while also improving the appearance. In addition, the canister CA can be easily installed in a narrow space within the vehicle body frame F.

[Brief explanation of drawings]

FIG. 1 is a partial side view of a motorcycle equipped with the device of the present invention;
2 is a view taken along the line ■--■ in FIG. 1, FIG. 3 is a longitudinal sectional side view of the canister, and FIG. 4 is a view taken along the line IV--■ in FIG. 3. C... Space, CA... Canister, F
...Body frame, p...Central frame pipe, 1...Engine body, 2...
・Rear wheel, 3...Seat, 4...Rear fork, 26...Purge air inlet, 27.
...Atmospheric suction port.

Claims (1)

[Scope of utility model registration request] An engine body 1, a rear wheel 2, and a seat 3 are arranged at the center, rear, upper, and lower parts of the vehicle body frame F, respectively.
and a canister device for adsorbing evaporative fuel in a motorcycle, in which a canister CA for adsorbing evaporative fuel supported by the body frame F is disposed in a space C surrounded by a rear fork 4, the purge air being opened to the canister CA. The inlet 26 is communicated with a central frame pipe p that extends in the vertical direction and constitutes a part of the vehicle body frame F, and an atmospheric air suction port 27 is opened at the upper part of the central frame pipe p. A canister device for adsorbing evaporated fuel in a motorcycle, characterized in that purge air is introduced into the canister A through a central frame pipe p1 and a purge air introduction port 26.