JP5231303B2 - Split canister - Google Patents

Description

  The present invention communicates a first chamber having a first opening communicating with a fuel tank and an internal combustion engine, a second chamber having a second opening communicating with the atmosphere, the first chamber and the second chamber. The present invention relates to a divided canister having a communication pipe.

  In general, an automobile or the like is provided with a canister (charcoal canister) that adsorbs evaporated fuel (vapor) generated in a fuel tank. The canister adsorbs the evaporated fuel released from the fuel tank, and purges the adsorbed evaporated fuel by sucking the atmosphere, and supplies it to the internal combustion engine side.

  For example, Patent Document 1 includes a main canister (adsorption chamber) that has an activated carbon layer that adsorbs evaporated fuel and communicates with the atmosphere, and a sub-canister (adsorption chamber) that communicates with an internal combustion engine. A so-called divided canister is disclosed in which the sub-canister is connected in series with each other through a communication pipe.

JP-A-8-218922

  Normally, this kind of divided canister, when the internal combustion engine is in a predetermined operating state, draws air from the adsorption chamber on the atmosphere communication side by the intake air of the internal combustion engine and purges the evaporated fuel adsorbed by the air. While being supplied to the internal combustion engine through the communication pipe and the other adsorption chamber. Such an air flow during the intake of the atmosphere tends to have a larger flow rate and flow velocity because the forced suction operation is performed by the internal combustion engine than when the evaporated fuel is adsorbed when the internal combustion engine is stopped. . For this reason, it is desirable to make the air flow smoother in the path communicating from the adsorption chamber on the atmosphere communication side to the adsorption chamber on the communication side related to the internal combustion engine. In particular, in a portion where air is circulated from the adsorption chamber on the atmosphere communication side to the connection port of the communication pipe, the flow path of the air is rapidly narrowed, so that it is necessary to make the flow smoother.

  In relation to such a point, in the configuration described in Patent Document 1, an air outflow chamber is provided in the main canister on the atmosphere communication side, and a connection port with the communication pipe is provided in the air outflow chamber. However, the air outflow chamber is merely a substantially cylindrical space using one end side of the adsorption chamber as it is, and air or the like remains in the room without being sucked into the connection port at the corner of the room. May interfere with smooth air flow.

  The present invention has been made in consideration of the above-described conventional problems, and an object of the present invention is to provide a divided canister that can further smooth the air flow from the chamber on the atmosphere communication side to the communication pipe.

  The split canister according to the present invention includes a first chamber having a first opening communicating with the fuel tank and the internal combustion engine, a second chamber having a second opening communicating with the atmosphere, the first chamber, and the second chamber. A split canister having a communication pipe communicating with a chamber, wherein the second chamber has a guide part that sends air flowing in from the second opening toward a connection port with the communication pipe, The guide portion is characterized in that the interior of the second chamber is defined so as to become narrower toward the connection port.

  The split canister according to the present invention includes a first chamber having a first opening communicating with the fuel tank and the internal combustion engine, a second chamber having a second opening communicating with the atmosphere, the first chamber, A split canister having a communication pipe communicating with the second chamber, wherein the second chamber has a guide portion that sends air flowing in from the second opening toward a connection port with the communication pipe. The guide portion is configured to pass through the interior of the second chamber so that the air flowing into the second chamber from the second opening is sent while turning from the second opening side to the connection port side. It is characterized by prescribing.

  According to such a configuration, the air flowing into the second chamber from the second opening is guided to the connection port with the communication pipe while being guided by the guide portion provided in the second chamber. As a result, with respect to the introduction of air from the second chamber, which is a part that causes the air flow as a whole of the apparatus to stagnate, it is effectively avoided that air stays in the second chamber. It can be smoothly distributed to the pipe. Therefore, not only the second chamber but also the air flow as a whole of the divided canister can be improved as much as possible.

  In addition, you may form the said guide part as a fan-shaped wall surface which becomes narrow toward the said connection port side from the said 2nd opening part side. The guide portion may be formed as a spiral wall surface or a spiral wall surface.

  According to the present invention, by providing the guide portion in the second chamber, the air flowing into the second chamber can be sent out to the connection port with the communication pipe while being guided by the guide portion. As a result, not only the second chamber but also the entire divided canister can be improved as much as possible.

It is a perspective explanatory view showing the configuration of the divided canister according to the first embodiment of the present invention. It is a partial cross-section back explanatory drawing of the division | segmentation canister shown in FIG. FIG. 3 is a cross-sectional explanatory view showing a second chamber constituting the divided canister shown in FIG. 2. FIG. 4 is a cross-sectional explanatory diagram illustrating a configuration in which a guide portion is omitted from the second chamber illustrated in FIG. 3. It is a section explanatory view showing the 2nd room which constitutes a division canister concerning a 2nd embodiment of the present invention. It is a partial cross section perspective explanatory view of the 2nd chamber shown in FIG. It is a section explanatory view showing the 2nd room which constitutes a division canister concerning a 3rd embodiment of the present invention. FIG. 8 is a partially omitted cross-sectional explanatory view taken along line VIII-VIII in FIG. 7.

  Hereinafter, preferred embodiments of the divided canister according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing a configuration of a split canister 10 according to the first embodiment of the present invention, and FIG. 2 is a partial cross-sectional rear view of the split canister 10 shown in FIG. The divided canister 10 is mounted on the rear portion of a vehicle such as a four-wheeled vehicle, and adsorbs evaporated fuel (vapor) generated in the fuel tank 12 in the first adsorption chamber 14 and the second adsorption chamber 16 and adsorbs the vaporized fuel (vapor). This is a device that purges evaporated fuel by atmospheric suction and supplies it to an engine (internal combustion engine) 18.

  As shown in FIGS. 1 and 2, the divided canister 10 has a first adsorption chamber 14 that adsorbs the evaporated fuel introduced from the fuel tank 12 and a first adsorption chamber 14 that adsorbs the evaporated fuel introduced from the first adsorption chamber 14. And a filter box 20 that communicates with the second adsorption chamber 16 and the atmosphere and prevents foreign substances such as dust contained in the atmosphere from entering the second adsorption chamber 16. Further, the divided canister 10 has a first chamber (main chamber) 24 communicating with one end side of the first adsorption chamber 14 through a first opening 22 (see FIG. 2) and a second chamber on one end side of the second adsorption chamber 16. The second chamber (sub chamber) 28 that communicates with the opening 26 (see FIG. 2), the first chamber 24, and the second chamber 28 are communicated, and thereby the first adsorption chamber 14 and the second adsorption chamber 16 are communicated. And a communication pipe 30.

  The first adsorption chamber 14 is configured by housing activated carbon, which is an adsorbent for evaporated fuel generated in the fuel tank 12, in a housing 32 having a substantially rectangular parallelepiped shape. A charge port 34 connected to the fuel tank 12 and a purge port 36 connected to the intake passage of the engine 18 are provided on the upstream side of the first adsorption chamber 14 (on the side opposite to the first chamber 24). . A pressure sensor 38 is installed in the charge port 34. The pressure sensor 38 has a vent pipe (not shown) communicating with the atmosphere, and can detect a differential pressure between the atmosphere and the pressure in the fuel tank 12.

  The first chamber 24 is connected to the downstream side wall of the first adsorption chamber 14. The first chamber 24 has a flat, substantially rectangular parallelepiped shape in which the housing 32 extends in the longitudinal direction (axial direction). As shown in FIG. 2, the first opening 22 is formed on the side wall on the first adsorption chamber 14 side. And a connection port 39 communicating with the communication pipe 30 is formed on the side wall on the second adsorption chamber 16 side.

  Similar to the first adsorption chamber 14, the second adsorption chamber 16 is configured by accommodating activated carbon, which is an adsorbent for evaporated fuel, in a housing 40 having a substantially cylindrical shape. The housing 40 has a smaller capacity than the housing 32 of the first adsorption chamber 14, and the filter box 20 is integrally formed on the side portion on the first adsorption chamber 14 side. The housing 40 and the filter box 20 are partitioned by an internal partition wall 42 and communicated with each other by communication ports 44 and 46.

  The second chamber 28 is connected to a side wall on the upstream side (communication pipe 30 side) of the second adsorption chamber 16. The second chamber 28 has a flat, generally cylindrical shape that extends the housing 40 in the longitudinal direction (axial direction). As shown in FIG. 2, the second opening 26 is formed on the side wall on the second adsorption chamber 16 side. And a connection port 48 communicating with the communication pipe 30 is formed on the side wall on the first adsorption chamber 14 side.

  Further, as shown in FIGS. 2 and 3, the air flowing from the second opening 26 through the filter box 20 and the second adsorption chamber 16 is guided to the second chamber 28 toward the connection port 48. A guide unit 50 is provided for feeding while feeding. In the case of the present embodiment, the guide portion 50 has a pair of guide plates 52 a and 52 b erected so as to partition the inside of the second chamber 28 along the longitudinal direction (axial direction) of the housing 40. As shown in FIG. 3, the guide plates 52 a and 52 b are narrower in the room from the second opening 26 side provided in the substantially central portion of the second chamber 28 toward the connection port 48 in the rear view (front view). The inside of the second chamber 28 is defined so as to be, that is, a fan-shaped wall surface that becomes narrower from the second opening 26 side toward the connection port 48 side.

  As shown in FIG. 1, the filter box 20 is fixed to the housing 40 of the second adsorption chamber 16 via a flange portion 49, and a well-known air filter medium (not shown) is accommodated therein. doing. A vent pipe 51 communicating with the atmosphere is provided on the downstream side wall (atmosphere communication side) of the filter box 20, and air sucked from the vent pipe 51 passes through a path (not shown) in the filter box 20 (for example, , Flow through a predetermined meandering path), and are then introduced into the second adsorption chamber 16 via the communication ports 46 and 44.

  Next, operations and effects of the divided canister 10 according to the present embodiment basically configured as described above will be described.

  First, when the engine 18 is in a stopped state or the like, the split canister 10 causes the evaporated fuel generated in the fuel tank 12 to flow through the charge port 34 through the first charge port 34, as indicated by solid arrows in FIGS. It is introduced into the adsorption chamber 14 and adsorbed by the activated carbon in the first adsorption chamber 14. Evaporated fuel that cannot be adsorbed in the first adsorption chamber 14 is introduced from the first chamber 24 into the second adsorption chamber 16 through the communication pipe 30 and the second chamber 28 and adsorbed on the activated carbon in the second adsorption chamber 16. Is done. This effectively prevents the evaporated fuel from being diffused into the atmosphere.

  On the other hand, when the engine 18 is in a predetermined operation state, the split canister 10 has a ventilation pipe 51 of the filter box 20 by intake air from the intake passage side of the engine 18 as indicated by a broken line arrow in FIGS. The atmosphere (air) is inhaled from. The air sucked into the filter box 20 purges the evaporated fuel adsorbed in the second adsorption chamber 16 and then flows into the second chamber 28 from the second opening 26, and this second chamber 28. The guide portion 50 (guide plates 52 a and 52 b) is guided to the connection port 48 while being guided by the guide portion 50 (guide plates 52 a and 52 b) (see FIG. 3), and is introduced into the first chamber 24 through the communication pipe 30. The air introduced into the first chamber 24 (air purged with evaporated fuel) is introduced into the first adsorption chamber 14 from the first opening 22 and is adsorbed in the first adsorption chamber 14. Is then sent to the intake passage of the engine 18 via the purge port 36.

  In this case, according to the divided canister 10 according to the present embodiment, when the atmosphere is sucked from the vent pipe 51 and the evaporated fuel adsorbed in the first adsorption chamber 14 and the second adsorption chamber 16 is purged, the atmosphere communication side The air that has flowed into the second chamber 28 from the second opening 26 is sent to the connection port 48 while being smoothly guided by the guide portion 50, and flows from the communication pipe 30 to the first chamber 24 side. Is done. That is, the inside of the second chamber 28 is formed in a substantially fan shape that tapers toward the connection port 48 by the guide plates 52 a and 52 b constituting the guide portion 50.

  Therefore, as shown in FIG. 3, the air (purged evaporated fuel) flowing from the second opening 26 does not stay in the second chamber 28 and is smoothly introduced into the communication pipe 30, so that the engine 18 side Can be distributed. For this reason, not only the second chamber 28 but also the air flow of the divided canister 10 as a whole is improved as much as possible, and the intake air in the engine 18 becomes smooth.

  In particular, the first and second adsorption chambers 14 and 16, which are at least two chambers, and the first chamber 24 and the second chamber 28 provided integrally therewith are provided, and the first chamber 24 and the second chamber 28 are provided. In the divided canister 10 in which the communication pipes 30 are connected to each other, the route from the second chamber 28 on the atmosphere communication side to the communication pipe 30 (connection port 48) is suddenly narrowed at the time of atmospheric suction. Therefore, the air is likely to stay in the second chamber 28, and this is a part that causes the air flow of the entire apparatus to stagnate. Therefore, in this embodiment, a smooth air flow can be obtained by providing the guide portion 50 that guides the air flow in the second chamber 28 and smoothly sends it to the connection port 48.

  In order to further enhance the effect of improving the air flow by the guide portion 50 narrowing toward the connection port 48 in this way, for example, the position of the second opening portion 26 for introducing air into the second chamber 28 is set. You may provide in the wall surface side spaced apart from the connection port 48 as shown by the dashed-two dotted line in FIG. Then, the retention of air in the second chamber 28 can be further reduced.

  On the other hand, FIG. 4 shows a configuration when the guide portion 50 is omitted from the second chamber 28. As can be understood from FIG. 4, the guide portion 50 is not provided in the second chamber 28, and the inside of the second chamber 28 is simply configured in a substantially cylindrical shape (or the same shape even in a substantially rectangular parallelepiped shape). In some cases, a linear flow from the second opening 26 toward the connection port 48 is generated, and in the periphery, stagnant air that is not substantially introduced into the connection port 48 is generated (in FIG. 4). It is difficult to send air smoothly to the engine 18 side.

  5 and 6 are explanatory diagrams of the second chamber 28a constituting the divided canister 10a according to the second embodiment of the present invention. 5 and 6, the same reference numerals as those shown in FIGS. 1 to 3 indicate the same or similar configurations, and thus are described in detail as having the same or similar functions and effects. The same shall apply hereinafter.

  As shown in FIGS. 5 and 6, the divided canister 10a according to this embodiment is different from the divided canister 10 according to the first embodiment in the second chamber instead of the second chamber 28 (see FIG. 3). The difference is that 28a is provided. In the second chamber 28a, a guide portion 54 having another shape is provided in place of the above-described substantially fan-shaped guide portion 50.

  The guide portion 54 includes a spiral (substantially involute) guide plate 56 erected so as to partition the inside of the second chamber 28 a in a spiral shape along the longitudinal direction (axial direction) of the housing 40. The guide plate 56 has a second opening 26 provided slightly above the center of the second chamber 28a in the rear view (front view), and the guide plate 56 turns from the air toward the connection port 48 so as to turn from there. It is a spiral-shaped wall surface.

  Therefore, when purging the evaporated fuel as described above, the air flowing into the second chamber 28a from the second opening 26 on the atmosphere communication side is smoothly guided by the guide portion 54, and the second It is sent to the connection port 48 while turning in the chamber 28a and circulated from the communication pipe 30 to the first chamber 24 side. For this reason, air (purged evaporated fuel) does not stay in the second chamber 28a, and can be smoothly introduced into the communication pipe 30 and circulated to the engine 18 side. The flow of air is improved as much as possible and becomes smooth, and intake by the engine 18 becomes smooth.

  7 and 8 are explanatory views of the second chamber 28b constituting the divided canister 10b according to the third embodiment of the present invention.

  As shown in FIGS. 7 and 8, the divided canister 10b according to the present embodiment is different from the divided canister 10 according to the first embodiment in the second chamber instead of the second chamber 28 (see FIG. 3). The difference is that 28b is provided. In the second chamber 28b, a guide portion 58 having another shape is provided in place of the above-described substantially fan-shaped guide portion 50.

  The guide portion 58 is partitioned by the guide plate 60a and a spiral guide plate 60a standing upright so as to partition the inside of the second chamber 28b along the longitudinal direction (axial direction) of the housing 40. And a guide plate 60b that regulates the flow path in a direction crossing the axial direction. The guide plates 60a and 60b turn around the second opening 26 provided slightly above the center of the second chamber 28 in rear view (front view) and gradually in the axial direction. The wall surface has a spiral shape (cyclone shape) that moves toward the connection port 48.

  Therefore, when purging the evaporated fuel as described above, the air flowing into the second chamber 28b from the second opening 26 on the atmosphere communication side is smoothly guided by the guide portion 58 while the second While turning inside the chamber 28b and gradually being sent to the back side of the second chamber 28b, it is sent to the connection port 48 and is circulated from the communication pipe 30 to the first chamber 24 side. For this reason, air (purged evaporated fuel) does not stay in the second chamber 28b, and can be smoothly introduced into the communication pipe 30 and circulated to the engine 18 side. The flow of air is improved as much as possible and becomes smooth, and intake by the engine 18 becomes smooth.

  The present invention is not limited to the above-described embodiment, and it is needless to say that various configurations and processes can be adopted without departing from the gist of the present invention.

  For example, the guide part provided in the second chamber on the second adsorption chamber 16 side may have a shape other than the above-described guide parts 50, 54, 58, and the main point is the second opening part on the atmosphere communication side. Any structure can be used as long as the air (purged evaporated fuel) flowing in from the air outlet 26 can be sent toward the connection port 48 while being smoothly guided, and the retention of air in the second chamber can be effectively reduced.

DESCRIPTION OF SYMBOLS 10, 10a, 10b ... Split canister 12 ... Fuel tank 14 ... 1st adsorption chamber 16 ... 2nd adsorption chamber 18 ... Engine 20 ... Filter box 22 ... 1st opening part 24 ... 1st chamber 26 ... 2nd opening part 28, 28a, 28b ... 2nd chamber 30 ... Communication pipe 39, 48 ... Connection port 50, 54, 58 ... Guide part 51 ... Ventilation pipe 52a, 52b, 56, 60a, 60b ... Guide plate

Claims (4)

A first chamber having a first opening communicating with the fuel tank and the internal combustion engine; a second chamber having a second opening communicating with the atmosphere; and a communication pipe communicating the first chamber and the second chamber. A split canister comprising:
The second chamber has a guide part that sends air flowing in from the second opening part toward a connection port with the communication pipe,
The divided canister is characterized in that the guide portion defines the interior of the second chamber so as to become narrower toward the connection port. The split canister according to claim 1, wherein
The divided canister according to claim 1, wherein the guide portion is a fan-shaped wall surface that becomes narrower from the second opening side toward the connection port side. A first chamber having a first opening communicating with the fuel tank and the internal combustion engine; a second chamber having a second opening communicating with the atmosphere; and a communication pipe communicating the first chamber and the second chamber. A split canister comprising:
The second chamber has a guide part that sends air flowing in from the second opening part toward a connection port with the communication pipe,
The guide section defines the interior of the second chamber so that air flowing into the second chamber from the second opening is sent while swirling from the second opening to the connection port. A split canister characterized by The split canister according to claim 3,
2. The divided canister according to claim 1, wherein the guide portion is a spiral wall surface or a spiral wall surface.

Images