Fuel tank and method of manufacturing the same

The present invention is to enable an adsorbent disposed in the vicinity of a tank port to be appropriately subjected to a purge when the adsorbent in a canister is subjected to the purge by air, thereby eliminating a non-desorption region of fuel vapor. In a fuel tank according to the present invention, a tank port (20t) that communicates with a space in a fuel tank body (10m), a purge port (20p), and an atmosphere port (20a) are formed in a container (21) of a canister (20) constituted by a container body (22) and a cover material (23), an inside of the container (21) of the canister (20) is configured to be partitioned to form passages (T1) and (T2) so that insides of the passages (T1) and (T2) are filled with an adsorbent (C), and the atmosphere port (20a) is provided on one end side in an air flow direction of the passages (T1) and (T2) and the tank port (20t) is provided on the other end side in the air flow direction of the passages (T1) and (T2) together with the purge port (20p).

TECHNICAL FIELD

The present invention relates to a fuel tank having a configuration in which a fuel tank body that stores fuel and a container body of a canister that stores an adsorbent to which fuel vapor is able to be adsorbed are integrally molded, and a method of manufacturing the same.

BACKGROUND ART

A technique related to the fuel tank described above is disclosed in JP-A-2008-168767.

As illustrated inFIG. 8, a fuel tank body100of the fuel tank is configured by joining an upper shell101and a lower shell (illustration is omitted). A container body122of a canister120is molded integrally with the inner side of the upper shell101at the ceiling portion. In the container body122of the canister120, an atmosphere port120aand a purge port120pare formed at positions of the ceiling portion of the upper shell101, and an opening portion122his formed at the lower end position of the container body122. In addition, the opening portion122hof the container body122is configured to be closed by a cover material124. A partition122wthat protrudes downward is formed at the ceiling portion of the container body122, and the atmosphere port120aand the purge port120pare separated by the partition122wto the left and the right. In addition, a vertical wall124wthat protrudes upward and is disposed parallel to the partition122wof the container body122is provided in a cover material124, and on the lower surface side of the cover material124positioned on the right of the vertical wall124w, a tank port120tincluding a bidirectional check valve is provided. That is, the inside of the container of the canister120is partitioned by the partition122wand the vertical wall124wand has a passage T formed to reach the purge port120pand the tank port120tfrom the atmosphere port120a. In addition, the inside of the passage T of the canister120is filled with an adsorbent C to which fuel vapor is adsorbed.

During a stop of an engine, when the pressure in the fuel tank body100is increased due to a temperature rise or the like, air and the fuel vapor in the fuel tank body100flow into the canister120via a cut-off valve111, a vapor passage112, and the bidirectional check valve of the tank port120t. In addition, the fuel vapor that flows in from the tank port120tis adsorbed to the adsorbent C such that only the air diffuses to the outside from the atmosphere port120a.

In addition, during driving of the engine, a negative pressure is applied to the purge port120pthat communicates with an intake passage (illustration is omitted) of the engine, air flows into the canister120from the atmosphere port120a, the air flows in the passage T to cause the adsorbent C to be subjected to a purge, and thus the fuel vapor is desorbed from the adsorbent C. In addition, the fuel vapor desorbed from the adsorbent C and the air are supplied to the intake passage of the engine from the purge port120p.

SUMMARY OF INVENTION

Technical Problem

In the fuel tank described above, the atmosphere port120ais positioned at the upstream end in the air flow direction of the passage T in the canister120, and the tank port120tis positioned at the downstream end in the air flow direction of the passage T. In addition, the purge port120pis positioned at an intermediate position in the air flow direction of the passage T.

Therefore, during driving of the engine, air that flows in from the atmosphere port120aflows between the atmosphere port120and the purge port120pand rarely flows to the downstream side from the purge port120p, that is, between the purge port120pand the tank port120t. As a result, the adsorbent C that fills the passage T between the purge port120pand the tank port120tcannot be appropriately purged, and thus a region in which the fuel vapor is not able to be desorbed from the adsorbent C is generated.

Accordingly, there has been a need for improved fuel tank in order, when an adsorbent in a canister is subjected to a purge by air in the canister having a container body molded integrally with a fuel tank, enable the adsorbent disposed in the vicinity of a tank port to be appropriately subjected to the purge, thereby eliminating a non-desorption region of fuel vapor.

BRIEF SUMMARY OF THE INVENTION

In a first aspect of this disclosure, a fuel tank has a configuration in which a fuel tank body that stores fuel and a container body of a canister that stores an adsorbent to which fuel vapor is able to be adsorbed are integrally molded, wherein, in a container of the canister constituted by the container body and a cover material, a tank port that communicates with a space in the fuel tank body, a purge port that is able to communicate with an intake passage of an engine, and an atmosphere port that is able to release atmosphere are formed, an inside of the container of the canister is configured to be partitioned to form passages so that insides of the passages are filled with the adsorbent, and the atmosphere port is provided on one end side in an air flow direction of the passages, and the tank port is provided on the other end side in the air flow direction of the passages together with the purge port.

According to the first aspect, the atmosphere port is provided on the one end side in the air flow direction of the passages formed in the container of the canister, and the tank port is provided on the other end side in the air flow direction of the passages together with the purge port. That is, the tank port is provided at the downstream end of the passages in the air flow direction together with the purge port.

Therefore, when a negative pressure of the intake passage is applied to the purge port due to operations of the engine and the air that flows into the container of the canister from the atmosphere port flows toward the other end side (the downstream end) from the one end side (the upstream end) of the passages, the air also flows to the vicinity of the tank port. As a result, the adsorbent disposed in the vicinity of the tank port is also appropriately subjected to a purge, thereby eliminating a non-desorption region of fuel vapor in the canister.

According to a second aspect of this disclosure, the atmosphere port, the tank port, and the purge port are disposed inside the fuel tank body.

According to a third aspect of this disclosure, the atmosphere port, the tank port, and the purge port are disposed outside the fuel tank body.

According to a fourth aspect of this disclosure, the container body of the canister is formed to traverse the space in the fuel tank body, and a wall portion provided with the atmosphere port and a wall portion provided with the tank port and the purge port oppose each other with the fuel tank body interposed therebetween.

Therefore, for example, it is possible to reinforce the fuel tank body from the inside by using the container body of the canister.

According to a fifth aspect of this disclosure, a vapor passage that causes the tank port of the canister and the space in the fuel tank body to communicate with each other is constituted by a wall surface of the fuel tank body and a cover member that covers the wall surface.

Therefore, it is possible to mold the vapor passage integrally with the fuel tank body.

According to a sixth aspect of this disclosure, the container of the canister is constituted by a groove-shaped container body formed on an upper surface of the fuel tank body and a cover material that blocks the groove-shaped container body, one end side and the other end side in a longitudinal direction of the groove-shaped container body respectively correspond to the one end side and the other end side in the air flow direction of the passages, an elastic body that presses the adsorbent is disposed between the adsorbent that fills the container body and the cover material, and a ventilation resistance of the elastic body is set to be greater than a ventilation resistance of an aggregated part of the adsorbent.

Therefore, when the adsorbent is subjected to the purge by air, the air does not flow along the elastic body and appropriately flows along the aggregated part of the adsorbent. Accordingly, even when the length dimension of the groove-shaped container body is large, the adsorbent may be appropriately subjected to the purge, and the depth dimension of the container body may be reduced by an increase in the length dimension. Therefore, the dimensions of the canister protruding toward the internal space of the fuel tank body may be reduced.

According to a seventh aspect of this disclosure, a step of integrally molding any one of an upper shell and a lower shell that constitute the fuel tank body, and the container body of the canister; a step of integrally molding the other of the upper shell and the lower shell, and the cover material of the container body of the canister; a filling step of filling the container body of the canister with the adsorbent of fuel vapor; and a step of joining the upper shell to lower shell after the filling step, and joining the container body of the canister to the cover material are included.

Therefore, molding of the fuel tank body and molding of the canister may be simultaneously performed.

Advantageous Effects of Invention

According to these aspects, when the adsorbent in the canister is subjected to a purge, the adsorbent disposed in the vicinity of the tank port is also able to be appropriately subjected to the purge, thereby eliminating a non-desorption region of fuel vapor in the canister.

DESCRIPTION OF EMBODIMENTS

Hereinafter, description of a fuel tank according to Embodiment 1 of the present invention will be provided on the basis ofFIGS. 1A to 3C. The fuel tank according to this embodiment is a fuel tank with a canister used in a vehicle.

<Summary of Fuel Tank10>

As illustrated inFIG. 1A, a fuel tank10includes a tank body10mconstituted by an upper shell12and a lower shell14. The upper shell12and the lower shell14are resin injection-molded products, and the surfaces thereof are covered with a barrier layer Ba having fuel permeation resistance. Here, as a resin that is a body material of the upper shell12and the lower shell14, for example, high-density polyethylene (HDPE) is used, and as a material of the barrier layer Ba, an ethylene vinyl alcohol copolymer (EVOH) is used. In addition, inFIGS. 2A to 4BandFIG. 7A to 7C, the barrier layer Ba of the fuel tank body10mis omitted.

The upper shell12is formed by an upper plate portion12uand a side plate portion12sin a square container shape in which the lower side thereof is open, and a flange portion12fis formed at the peripheral edge of a lower side opening12h. In addition, a container body22of a canister20described later is integrally molded at a predetermined position of the upper plate portion12uof the upper shell12.

As illustrated inFIG. 1A, the lower shell14is formed by a bottom plate portion14dand a side plate portion14sin a square container shape in which the upper side thereof is open, and a flange portion14fis formed at the peripheral edge of an upper side opening14h. A fuel pump unit30constituted by a fuel pump for pressure-feeding fuel to an internal combustion engine E, a pressure control mechanism, a sub-tank, and the like is mounted onto the bottom plate portion14d(bottom surface) of the lower shell14. In addition, a pipe connection portion32cof a fuel pipe32of the fuel pump unit30, and a connector34cof an electrical cable34of the fuel pump unit30are fixed to the side plate portion14sof the lower shell14.

In addition, the flange portion14fof the lower shell14and the flange portion12fof the upper shell12are joined to each other, thereby forming the fuel tank body10m.

The canister20is configured to enable adsorption of fuel vapor which is generated in the fuel tank body10mduring parking of a vehicle (an engine stopped state) and enable the adsorbed fuel vapor to be supplied to an intake pipe W of the engine E during driving. As illustrated in FIG.1(14the canister20includes a sealed type container21, and the container21is constituted by the container body22of an upside open type and a cover material23that blocks an upper portion opening22hof the container body22.

The container body22is formed in a square convex shape at a predetermined position of the upper plate portion12uof the upper shell12, and as described above, is molded integrally with the upper shell12. A partition22wis formed in a fence shape at a position of the upper surface of the lower plate portion22b(bottom surface) in the container body22, and the inside of the container body22is partitioned by the partition22wto the left and the right excluding the vicinity of the upper portion opening22has illustrated inFIG. 1B. That is, in the container body22, a left passage T1and a right passage T2that communicate with each other at the upper portion are provided. In addition, the lower portion of the right passage T2of the container body22is divided to the left and the right by a low vertical wall22yformed to be parallel to the partition22w.

In the bottom plate portion22bof the container body22, an atmosphere port20a, a purge port20p, and a tank port20tincluding a bidirectional check valve are formed to protrude downward (to protrude toward the internal space of the fuel tank10). That is, the atmosphere port20a, the purge port20p, and the tank port20tare disposed on the inside of the fuel tank body10m.

The bidirectional check valve of the tank port20tis a valve for suppressing a change in the internal pressure caused by expansion and contraction of the fuel tank body10mdue to a temperature change and the like, and is opened when the pressure in the fuel tank body10mis increased to a predetermined pressure or higher, or when the pressure in the fuel tank body10mis reduced to a predetermined negative pressure or less.

Here, the atmosphere port20acommunicates with the left passage T1of the container body22via a first filter F1, and the purge port20pcommunicates with the left of the vertical wall22yin the right passage T2of the container body22via a second filter F2. In addition, the tank port20tcommunicates with the right of the vertical wall22yin the right passage T2of the container body22via a third filter F3.

The left passage T1and the right passage T2of the container body22are filled with an adsorbent C made of granular activated carbon or the like from the upper portion opening22hof the container body22. In addition, in a state where the absorbent C is filled in the container body22, the entire upper surface of an aggregated part of the adsorbent C is covered with a plate-like elastic body25(for example, urethane, rubber, or the like). Next, the cover material23covers the elastic body25to press the elastic body25, and the peripheral edge of the cover material23is joined to the peripheral edge of the upper portion opening22hof the container body22. Here, the elastic body25is elastically deformed by being pressed by the cover material23and thus the aggregation part of the adsorbent C receives a pressing force of the elastic body25from the above.

The tank port20tof the canister20is connected to a cut-off valve16mounted to the ceiling portion of the fuel tank body10mvia the vapor pipe15. The cut-off valve16is a valve that is closed by an overturning of a vehicle or the like and is typically held in an open state.

The purge port20pof the canister20is connected to a tank side purge port12pprovided in the upper plate portion12uof the fuel tank body10mvia a purge pipe18t. In addition, an outside purge pipe18pthat is able to communicate with the intake pipe W of the engine E is connected to the tank side purge port12p.

In addition, the atmosphere port20aof the canister20is connected to a tank side atmosphere port12aprovided in the upper plate portion12uof the fuel tank body10mvia an atmosphere pipe19. In addition, the tank side atmosphere port12ais open to the atmosphere.

The upper shell12including the canister20and the lower shell14to which the fuel pump unit30is mounted are joined by, for example, a hot plate welding method. That is, first, the joining surface of the flange portion12fof the upper shell12is caused to come into contact with the upper surface of a flat hot plate (illustration is omitted) so as to be fused, and the joining surface of the flange portion14fof the lower shell14is caused to come into contact with the lower surface of the iron plate so as to be fused. Next, the upper shell12and the lower shell14are removed from the hot plate, and the joining surface of the flange portion12fof the upper shell12is aligned with the joining surface of the flange portion14fof the lower shell14. Accordingly, the upper shell12and the lower shell14are welded through the flange portions12fand14fthereof such that the fuel tank20is configured.

Here, procedures of causing the joining surfaces of the upper shell12and the lower shell14to come into contact with the hot plate so as to be fused may be simultaneously performed as described above, or any one may be performed first and the other may be performed later.

Next, the actions of the canister20in the fuel tank10according to this embodiment will be simply described.

In a stopped state of the engine E, for example, when the pressure in the fuel tank10becomes equal to or higher than a set pressure of the bidirectional check valve of the tank port20tdue to a temperature rise, the bidirectional check valve is opened. Accordingly, gas (fuel vapor+air) in the fuel tank10flows into the canister20through the cut-off valve16, the vapor pipe15, and the bidirectional check valve of the tank port20t. The fuel vapor that flows into the canister20is adsorbed to the adsorbent C while flowing upward in the right passage T2, and the fuel vapor guided to the left passage T1from the right passage T2is further adsorbed to the adsorbent C while flowing downward in the left passage T1. In addition, air from which the fuel vapor is removed diffuses to the outside via the atmosphere pipe19and the tank side atmosphere port12aof the fuel tank body10mfrom the atmosphere port20a. That is, as the air in the fuel tank body10mis released to the outside, the pressure of the fuel tank body10mis not increased to a predetermined value or higher, thereby achieving protection of the fuel tank body10m.

Here, when the pressure in the fuel tank10is lower than the set pressure of the bidirectional check valve of the tank port20t, the bidirectional check valve is closed, and thus the fuel vapor is sealed in the fuel tank10and does not leak out.

In addition, in the stopped state of the engine E, for example, when the pressure in the fuel tank10is reduced to be lower than a set negative pressure of the bidirectional check valve of the tank port20tdue to a temperature drop, the bidirectional check valve is opened. Accordingly, outside air is guided from the tank side atmosphere port12a, the atmosphere pipe19, and the atmosphere port20aof the canister20into the canister20and thus flows into the fuel tank body10mthrough the bidirectional check valve of the tank port20t. That is, as air flows into the fuel tank body10mfrom the outside, the pressure of the fuel tank body10mis not reduced to the predetermined negative pressure or less, thereby achieving protection of the fuel tank body10m.

Next, when the inside of the intake pipe W has a negative pressure due to driving of the internal combustion engine E, the inside of the canister20has a negative pressure via the outside purge pipe18p, the tank side purge port12pof the fuel tank body10m, the purge pipe18t, and the purge port20pof the canister20. Accordingly, air flows into the canister20from the tank side atmosphere port12a, the atmosphere pipe19, and the atmosphere port20aof the canister20, and the air flows upward in the left passage T1, reaches the right passage T2, flows downward in the right passage T2, and is taken into the intake pipe W of the engine E via the purge port20p, the purge pipe18t, the tank side purge port12p, and the outside purge pipe18p. In addition, the fuel vapor adsorbed to the adsorbent C is purged while the air flows into the right passage T2from the left passage T1so as to be desorbed from the adsorbent C, and the fuel vapor that is desorbed is supplied into the intake pipe W of the engine E along with the air.

That is, the lower end of the left passage T1provided with the atmosphere port20aof the canister20corresponds to one end side (upstream side) in the air flow direction of the passages in the present invention, and the lower end of the right passage T2provided with the tank port20tand the purge port20pcorresponds to the other end side (downstream side) in the air flow direction of the passages in the present invention.

<Advantages of Fuel Tank10according to this Embodiment>

According to the fuel tank10according to this embodiment, the atmosphere port20ais provided on the one end side in the air flow direction of the passages T1and T2formed in the container21of the canister20, and the tank port20tis provided on the other end side in the air flow direction of the passages T1and T2together with the purge port20p. That is, the tank port20tis provided at the downstream end of the passages T1and T2together with the purge port20pin the air flow direction.

Therefore, when a genitive pressure of the intake pipe W is applied to the purge port20pdue to operations of the engine E and the air that flows into the container21of the canister20from the atmosphere port20aflows toward the other end side (the downstream side) from the one end side (the upstream end) of the passages T1and T2, the air also flows to the vicinity of the tank port20t. As a result, the adsorbent C disposed in the vicinity of the tank port20tis also appropriately subjected to a purge, thereby eliminating a non-desorption region of fuel vapor in the canister20.

Modification Example

Here, the present invention is not limited to the above-described embodiment, and may be modified in a scope that does not depart from the gist of the present invention. For example, in the fuel tank10according to this embodiment, an example in which the tank port20t, the purge port20p, and the atmosphere port20aof the canister20are provided inside the fuel tank body10mis illustrated. However, as illustrated inFIGS. 2A and 2B, it is possible to form the tank port20t, the purge port20p, and the atmosphere port20ain the upper plate portion12uof the fuel tank body10mby modifying the container body22of the canister20.

That is, the container body22of the canister20according to the modification example is a square container in which the upper end side (the upper plate portion12uside of the fuel tank body10m(the upper shell12)) is closed and the lower end side is open, and is molded integrally with the upper shell12. In the container body22, the partition22wis formed at the ceiling portion of the container body22to protrude downward in the fence shape, and the inside of the container body22is partitioned by the partition22wto the left and the right excluding the vicinity of the lower portion opening22h. That is, in the container body22, the left passage T1and the right passage T2that communicate with each other at the lower portion are provided. In addition, the upper portion of the right passage T2of the container body22is divided to the left and the right by the low vertical wall22yformed to be parallel to the partition22w.

In the ceiling plate (the upper plate portion12uof the upper shell12) of the container body22, the atmosphere port20a, the purge port20p, and the tank port20tare formed to protrude upward. That is, the atmosphere port20a, the purge port20p, and the tank port20tare disposed on the outside of the fuel tank body10m. In addition, the atmosphere port20acommunicates with the left passage T1of the container body22via the first filter F1, and the purge port20pcommunicates with the left of the vertical wall22yin the right passage T2of the container body22via the second filter F2. In addition, the tank port20tcommunicates with the right of the vertical wall22yin the right passage T2of the container body22via the third filter F3.

As illustrated inFIG. 2B, the left passage T1and the right passage T2of the container body22are filled with the adsorbent C after each of the first, second, and third filters F1, F2, and F3is set from the lower portion opening22hof the container body22in a state where the upper shell12is vertically reversed. In addition, in a state where the adsorbent C is filled in the container body22, the entire upper surface of an aggregated part of the adsorbent C (the entirety of the upper surface inFIG. 2Bis covered with a filter23f, and the filter23fis pressed by a pressing flat plate23b. Moreover, in a state where a spring23sis set between the pressing plate23band the cover material23, the peripheral edge of the cover material23is joined to the peripheral edge of the lower portion opening22hof the container body22. Accordingly, the aggregation part of the adsorbent C receives a pressing force from the above due to the action of the spring23s.

The canister20(seeFIG. 2A) according to this modification example has substantially the same configuration as that of the canister20illustrated inFIG. 1Aand is different only in the positions of the atmosphere port20a, the purge port20p, and the tank port20t, and thus description of the operations of the canister20according to this modification example will be omitted.

In addition, in the fuel tank according to the modification example, the bidirectional check valve in the tank port20tof the canister20is omitted, and thus a fill-up regulating valve16vis provided at the tip position of the vapor pipe15as illustrated inFIGS. 2A and 2. Here, the fill-up regulating valve16vis a valve that prevents a fuel liquid level in the fuel tank body10mfrom exceeding the upper limit value during fueling, and is held in a closed state when the fuel tank is filled up and held in an open state except when the fuel tank is filled up.

In addition, inFIGS. 2A and 2B, an example in which the tank port20tand the cut-off valve16, and the cut-off valve16and the fill-up regulating valve16vare connected with the vapor pipe15is illustrated. However, as illustrated inFIG. 2C, a groove portion15mthat connects the tank port20tto the cut-off valve16and connects the cut-off valve16to the fill-up regulating valve16vmay be formed in the upper plate portion12uof the upper shell12, and a vapor passage may be formed by covering the opening portion of the groove portion15mwith a cover portion15c. Accordingly, a part (the groove portion15m) of the vapor passage may be molded integrally with the upper shell12, resulting reduction in cost.

In the fuel tank according to the modification example ofFIGS. 2A to 2C, an example in which the lower portion opening22hof the container body22of the canister20is covered by the cover material23is illustrated. However, as illustrated inFIG. 3A, the lower portion opening22hof the container body22may be covered by a flat portion14xformed in the lower shell14.

That is, the container body22of the canister20formed in the upper shell12is formed to be vertically long, and the lower end surface of the container body22is positioned on the same plane as the joining surface of the flange portion12fof the upper shell12.

In addition, in the lower shell14, a square protrusion is formed at a position corresponding to the container body22of the canister20, and the upper surface of the protrusion becomes the flat portion14xwhich is flat. In addition, the flat portion14xof the protrusion is positioned on the same plane as the joining surface of the flange portion14fof the lower shell14.

Therefore, the container body22of the canister20is filled with the adsorbent C, and in a state where the lower portion opening22hof the container body22is temporarily blocked by an elastic body25(for example, urethane, rubber, or the like), the upper shell12and the lower shell14may be joined by, for example, a hot plate welding method.

That is, first, the joining surface of the flange portion12fof the upper shell12and the lower end surface of the container body22are caused to come into contact with the upper surface of a flat hot plate (illustration is omitted) so as to be fused, and the joining surface of the flange portion14fof the lower shell14and the flat portion14xof the protrusion are caused to come into contact with the lower surface of the iron plate so as to be fused. Next, the upper shell12and the lower shell14are removed from the hot plate, and the joining surface of the flange portion12fof the upper shell12is aligned with the joining surface of the flange portion14fof the lower shell14, and the lower end surface of the container body22of the upper shell12is aligned with the flat portion14xof the protrusion of the lower shell14. Accordingly, the flange portion12fof the upper shell12and the flange portion14fof the lower shell14are welded to each other, and the lower portion opening22hof the container body22and the flat portion14xof the protrusion are welded to each other, thereby blocking the lower portion opening22hof the container body22. In this manner, the lower portion opening22hof the container body22may be blocked simultaneously with joining between the flange portion12fof the upper shell12and the flange portion14fof the lower shell14, and thus molding of the fuel tank body10mand the molding of the canister20may be simultaneously performed.

In addition, as illustrated inFIG. 3B, by disposing the canister20at the end portion of the fuel tank body10m, the lower portion opening22hof the container body22of the canister20may be blocked by the flange portion14fof the lower shell14.

Hereinafter, description of a fuel tank according to Embodiment 2 of the present invention will be provided on the basis ofFIGS. 4A and 4B. The fuel tank according to this embodiment is made by changing the shapes and the like of the container body22of the canister20according to Embodiment 1, and the configurations other than the container body22are the same as the configurations of the fuel tank10according to Embodiment 1. Therefore, in the fuel tank according to this embodiment, like elements that are the same as those of the fuel tank10according to Embodiment 1 are denoted by like reference numerals, and description thereof will be omitted.

A container upper side portion43that is included in a container body40of the canister20is formed in the upper shell12included in the fuel tank body10mof the fuel tank according to this embodiment. The container upper side portion43is a portion that is molded integrally with the upper shell12and is formed in a substantially cylindrical shape. In addition, an upper end portion43wof the container upper side portion43expands in a funnel shape, and the peripheral edge portion thereof is configured to be continuous from the upper plate portion12uof the upper shell12. In addition, a through-hole43kis formed at the center of the bottom portion of the container upper side portion43, and a joint ring portion43ris formed on the lower side of the bottom portion coaxially with the through-hole43kto surround the through-hole43k. In addition, the lower end surface of the joint ring portion43rof the container upper side portion43is positioned on the same plane as the joining surface (lower end surface) of the flange portion12fof the upper shell12.

The filter F1is set in the container upper side portion43to cover the through-hole43kat the bottom portion, and the upper side of the filter F1is filled with the adsorbent C. In addition, in a state where the filter F2covers the upper surface of an aggregated part of the adsorbent C, an upper portion opening43hof the container upper side portion43is blocked by an upper portion cover material46.

In the upper portion cover material46, the tank port20tand the purge port20pare formed to protrude outward from the fuel tank body10m. In addition, on the inner side of the upper portion cover material46, a vertical wall46ythat is formed to be distant from the tank port20tand the purge port20pon the inner side of the container upper side portion43is formed.

A container lower side portion45that is included in the container body40of the canister20is formed in the lower shell14included in the fuel tank body10m. The container lower side portion45is formed to be vertically symmetrical to the container upper side portion43of the upper shell12. That is, a lower end portion45wof the container lower side portion45expands in a funnel shape, and the peripheral edge portion thereof is configured to be continuous from the bottom plate portion14dof the lower shell14. In addition, a through-hole45kis formed at the center of the ceiling portion of the container lower side portion45, and a joint ring portion45ris formed on the upper side of the ceiling portion coaxially with the through-hole43kto surround the through-hole45k. In addition, the upper end surface of the joint ring portion45rof the container lower side portion45is positioned on the same plane as the joining surface (upper end surface) of the flange portion14fof the lower shell14.

The filter F3is set in the container lower side portion45to cover the through-hole45kat the ceiling portion from the inside, and the inside of the container lower side portion45is filled with the adsorbent C. In addition, in a state where a filter F4covers an aggregated part of the adsorbent C, a lower portion opening45hof the container lower side portion45is blocked by a lower portion cover material47.

In the lower portion cover material47, the atmosphere port20ais formed to protrude outward from the fuel tank body10m.

<Method of Manufacturing Fuel Tank10>

First, the container upper side portion43of the upper shell12side is filled with the adsorbent C as described above, and the upper portion opening43hof the container upper side portion43is closed by the upper portion cover material46. In addition, the container lower side portion45of the lower shell14side is similarly filled with the adsorbent C, and the lower portion opening45hof the container lower side portion45is closed by the lower portion cover material47. Next, the upper shell12and the lower shell14are joined by, for example, a hot plate welding method. That is, first, the joining surface of the flange portion12fof the upper shell12and the lower end surface of the joint ring portion43rof the container upper side portion43are caused to come into contact with the upper surface of a flat hot plate (illustration is omitted) so as to be fused, and the joining surface of the flange portion14fof the lower shell14and the upper end surface of the joint ring portion45rof the container lower side portion45are caused to come into contact with the lower surface of the iron plate so as to be fused. Next, in a state where the upper shell12and the lower shell14are removed from the hot plate, the joining surface of the flange portion12fof the upper shell12is aligned with the joining surface of the flange portion14fof the lower shell14, and the lower end surface of the joint ring portion43rof the container upper side portion43is aligned with the upper end surface of the joint ring portion45rof the container lower side portion45. Accordingly, the flange portion12fof the upper shell12and the flange portion14fand the lower shell14are fused to each other, and the lower end surface of the joint ring portion43rof the container upper side portion43and the upper end surface of the joint ring portion45rof the container lower side portion45are fused to each other. That is, the fuel tank body10mis constituted by the upper shell12and the lower shell14, and the canister20is simultaneously formed by the container upper side portion43and the container lower side portion45.

<Advantages of Fuel Tank According to this Embodiment>

According to the fuel tank according to this embodiment, the container body40of the canister20is formed to vertically traverse the space in the fuel tank body10m, and a wall portion (the lower portion cover material47) provided with the atmosphere port20aand a wall portion (the upper portion cover material46) provided with the tank port20tand the purge port20poppose each other with the fuel tank body10minterposed therebetween.

Therefore, the fuel tank body10mmay be reinforced from the inside by using the container body40of the canister20.

Hereinafter, description of a fuel tank according to Embodiment 3 of the present invention will be provided on the basis ofFIGS. 5A,5B and6. The fuel tank according to this embodiment is made by changing the container bodies22and40of the canister20according to Embodiments 1 and 2 so that a container body50is formed to be thin and long on the upper surface of the fuel tank body10mas illustrated inFIG. 5B. In addition, in the fuel tank according to this embodiment, the configurations other than the container body50are the same as those of the fuel tank10according to Embodiment 1. Therefore, like elements that are the same as those of the fuel tank10according to Embodiment 1 are denoted by like reference numerals, and description thereof will be omitted.

As illustrated inFIG. 5B, the container body50of the canister20according to this embodiment is formed in a groove shape that gradually meanders on the upper surface of the fuel tank body10m(the upper shell12) and is molded integrally with the upper shell12. The inside of the container body50is partitioned by an first partition plate portion51that is provided in the vicinity of one end side in the longitudinal direction (in the vicinity of the left end inFIGS. 5A,5B and6) and has air permeability and a second partition plate portion52that is provided in the vicinity of the other end side (in the vicinity of the right end inFIGS. 5A,5B and6) and has air permeability into a left end chamber R1, a passage T, and a right end chamber R2. As illustrated inFIG. 6, a first filter51fis provided on the passage T side of the first partition plate portion51, and a second filter52fis provided on the passage T side of the second partition plate portion52. In addition, the passage T of the container body50is filled with the adsorbent C at a position between the first and second filters51fand52f. In a state where the upper surface of the aggregated part of the adsorbent C that fills the passage T of the container body50is covered with an elastic body53(for example, urethane, rubber, or the like), an upper portion opening50h(seeFIG. 5B) of the container body50is blocked by a cover material55.

Here, a material having a sufficiently greater ventilation resistance than the ventilation resistance of the aggregated part of the adsorbent C that fills the passage T is used for the elastic body53. Therefore, air or the like that flows in the passage T of the container body50does not flow along a part of the elastic body53and mainly passages through a part of the adsorbent C.

As described above, the cover material55is a flat plate that blocks the upper portion opening50hof the container body50, and as illustrated inFIG. 5A, is molded in a shape that gradually meanders similarly to the container body50. The purge port20pis provided in the left end portion of the surface of the cover material55, and the atmosphere port20ais formed in the right end portion of the surface of the cover material55. In addition, in a state where the cover material55blocks the upper portion opening50hof the container body50, as illustrated inFIG. 6, the atmosphere port20acommunicates with the right end chamber R2of the container body50, and the purge port20pcommunicates with the left end chamber R1of the container body50. In addition, as illustrated inFIG. 6, the left end chamber R1of the container body50is able to communicate with the tank port120tvia a bidirectional check valve56.

In the above-described canister20, when a negative pressure is applied to the purge port20pby driving of the engine E, air flows into the right end chamber R2of the container body50from the atmosphere port20a, and the air flows to the left in the passage T and is taken into the intake pipe W of the engine E from the left end chamber R1and the purge port20p. In addition, fuel vapor that is adsorbed to the adsorbent C is desorbed from the adsorbent C while the air flows to the left in the passage T, and the fuel vaport that is desorbed is supplied into the intake pipe W of the engine E along with the air. As described above, for the elastic body53that presses the adsorbent C from the above the material having a sufficiently greater ventilation resistance than the ventilation resistance of the aggregated part of the adsorbent C that fills the passage T is used. Therefore, the air and the like that flows in the passage T of the container body50does not pass through a part of the elastic body53and mainly passes through a part of the adsorbent C. Therefore, even though the passage T is formed to be log, an efficiency of the fuel vapor being desorbed from the adsorbent C is not reduced.

That is, even when the length dimension of the groove-shaped container body50is large, the adsorbent C may be appropriately subjected to the purge, and thus the length dimension may be increased. In addition, the depth dimension of the container body50may be reduced by an increase in the length dimension of the container body50. Therefore, the dimensions of the canister protruding toward the internal space of the fuel tank body10mmay be reduced.

Modification Example

Here, the present invention is not limited to Embodiments 1, 2, and 3 described above, and may be modified in a scope that does not depart from the gist of the present invention. For example, in Embodiments 1, 2, and 3, an example in which the fuel tank body10mis constituted by the upper shell12and the lower shell14is illustrated. However, as illustrated inFIG. 7A, the fuel tank body10mmay also be constituted by a left shell62to which the canister20is mounted and a right shell64to which the fuel pump unit30is mounted. Here, it is preferable that a plurality of kinds of left shells62be prepared depending on the size of the canister20and the right shell64be used in common. In addition, a configuration in which horizontal position adjustment of the fuel pump unit30is possible to fit the size of the fuel tank body10mas illustrated inFIG. 7Bis preferable.

In addition, as illustrated inFIG. 7C, the fuel tank body10mmay also be configured by a left shell62, an intermediate shell65, and a right shell64.

In addition, inFIGS. 1A and 1Bof Embodiment 1 of the present invention, an example in which the adsorbent C that fills the container body22of the canister20is pressed by using the elastic force of the plate-like elastic body25is illustrated. However, as illustrated inFIG. 2A, a configuration in which pressing is achieved by the pressing flat plate23band the spring23sis also possible. Contrary to this, as illustrated inFIG. 2A, instead of pressing the adsorbent C that fills the container body22with the pressing flat plate23band the spring23s, a configuration in which pressing is achieved by using the elastic force of the elastic body25is also possible.