JP4394104B2 - Evaporative fuel adsorbent - Google Patents

Description

  The present invention relates to an evaporated fuel adsorbent disposed inside an air cleaner connected to an engine, for example.

  In recent years, due to stricter regulations on HC (hydrocarbon) released from the vehicle when the vehicle is stopped, the fuel remaining in the engine or the fuel leaked from the injector when the vehicle is stopped may vaporize and leak from the intake port. It is a problem.

  Therefore, as disclosed in Japanese Utility Model Publication No. 62-35883, an evaporative fuel adsorbent such as a filter containing activated carbon is installed in the vicinity of an intake duct, an air cleaner, etc. to prevent evaporative fuel from leaking from the intake port. Intake system evaporative fuel adsorbing devices to prevent are considered.

Japanese Utility Model Sho 62-35883

    An object of the present invention is to provide an evaporative fuel adsorbent that can adsorb high-boiling components.

The evaporated fuel adsorbent according to the first aspect of the present invention is disposed in a passage inside an air cleaner connected to an internal combustion engine, and has a plate-like evaporated fuel adsorption having an adsorbate for adsorbing evaporated fuel flowing back from the internal combustion engine side. The adsorbate comprises a low-boiling component adsorbent that adsorbs a low-boiling component of the evaporated fuel and a high-boiling component adsorbent that adsorbs a high-boiling component of the evaporated fuel. The material has a low-boiling component adsorbent containing the low-boiling component adsorbent and a high-boiling component adsorbent containing the high-boiling component adsorbent, and the low-boiling component adsorbent and the high-boiling component Adsorbents are stacked in the thickness direction, the low-boiling component adsorbent is disposed on the internal combustion engine side, and the high-boiling component adsorbent is disposed vertically below the passage.

Next, the function and effect of the evaporated fuel adsorbent according to claim 1 will be described.

  According to the evaporated fuel adsorbent of the present invention, the low boiling point component of the evaporated fuel can be adsorbed by the low boiling point component adsorbent. Further, the high boiling point component of the evaporated fuel can be adsorbed by the high boiling point component adsorbent.

In particular, the low boiling point component adsorbent and the high boiling point component adsorbent are stacked in the thickness direction, the low boiling point component adsorbent is disposed on the internal combustion engine side, and the high boiling point component adsorbent is disposed vertically below the passage . Therefore, the low boiling point component of the evaporated fuel in the entire air cleaner can be adsorbed, and the high boiling point component of the evaporated fuel drifting on the bottom surface side of the air cleaner can also be adsorbed efficiently.

According to a second aspect of the present invention, there is provided the evaporative fuel adsorbent according to the first aspect , wherein the low-boiling point component adsorbent is thickened in a vertically downward direction of the passage, It is characterized by increasing the content vertically downward .

Next, the function and effect of the evaporated fuel adsorbent according to claim 2 will be described.

  In the air cleaner, the low-boiling components of the evaporated fuel are not necessarily distributed uniformly, and the concentration of the low-boiling components is usually caused by the influence of gravity or the like.

Therefore, in the present invention, the content in the vertical direction of the passage of the low boiling point component adsorbent contained in the low boiling point component adsorbent is increased or decreased according to the concentration in the vertical direction of the low boiling point component passage of the evaporated fuel. That is, the thickness of the low-boiling component is increased in the downward vertical direction, and the content of the low-boiling component adsorbate is increased in the downward vertical direction. By doing so, the low boiling point component of the evaporated fuel can be adsorbed efficiently.

According to a third aspect of the present invention, in the evaporative fuel adsorbing material according to the first or second aspect, the high boiling point component adsorbing material is made thicker vertically below the passage, and the high boiling point component adsorbing material is adsorbed. It is characterized by increasing the content of objects vertically downward .

Next, the function and effect of the evaporated fuel adsorbent according to claim 3 will be described.

  In the air cleaner, the high-boiling components of the evaporated fuel are not necessarily distributed uniformly, and usually the concentration difference of the high-boiling components is caused by the influence of gravity or the like.

Therefore, in the present invention, the content in the vertical direction of the high-boiling component adsorbent contained in the high-boiling component adsorbent is increased or decreased in accordance with the vertical concentration of the high-boiling component passage of the evaporated fuel. That is, the thickness of the high boiling point component is increased toward the lower vertical direction, the content of the high boiling point component adsorbate is increased downward in the vertical direction , and the content is decreased when the concentration of the high boiling point component is low. By doing so, it is possible to efficiently adsorb the high boiling point component of the evaporated fuel.

According to a fourth aspect of the present invention, there is provided an evaporative fuel adsorbent comprising a plate-like evaporative fuel adsorbent having an adsorbate for adsorbing an evaporative fuel flowing back from the internal combustion engine side, disposed in a passage inside an air cleaner connected to the internal combustion engine. The adsorbate comprises a low-boiling component adsorbent that adsorbs a low-boiling component of the evaporated fuel and a high-boiling component adsorbent that adsorbs a high-boiling component of the evaporated fuel, and the evaporated fuel adsorbent Has a low-boiling component adsorbent containing the low-boiling component adsorbent and a high-boiling component adsorbent containing the high-boiling component adsorbent, and the low-boiling component having the same volume in the passage. The adsorbent and the high-boiling component adsorbent are overlapped in the thickness direction with the low-boiling component adsorbent disposed on the internal combustion engine side, and the low-boiling component adsorbent is directed vertically upward. thick, vertically under the high-boiling component adsorbent And thicker toward the is characterized in that it has a constant sum of the low-boiling component adsorbent and the height of the air flow direction of boiling component adsorbent thickness.

Next, the effect of the evaporative fuel adsorbent according to claim 4 will be described.

A low-boiling component adsorbent and a high-boiling component adsorbent having the same volume are stacked in the thickness direction with the low-boiling component adsorbent disposed on the internal combustion engine side , and the low-boiling component adsorbent is directed vertically upward. The thickness is increased and the high boiling point component adsorbent is directed vertically downward to increase the thickness, and the total thickness of the low boiling point component adsorbent and the high boiling point component adsorbent in the air flow direction is made constant. Thereby, the pressure loss in all the portions of the evaporated fuel adsorbent can be made uniform.

  ADVANTAGE OF THE INVENTION According to this invention, the evaporative fuel adsorbent which can adsorb | suck the high boiling point component of evaporative fuel efficiently can be provided.

  [First embodiment]

  Hereinafter, an evaporated fuel adsorbent according to a first embodiment of the present invention will be described with reference to the accompanying drawings.

  As shown in FIG. 1, the HC adsorbing sheet 10 (evaporated fuel adsorbing material) is disposed inside an air cleaner 14 provided on the upstream side of the engine 12 (internal combustion engine).

  Here, the structure of the engine 12 is conventionally known, and a piston 18 that is operated by a link mechanism 16 or the like is disposed inside the engine 12. The engine 12 is provided with an intake valve 20. An intake port 22 is formed outside the intake valve 20, and an injector 26 for injecting gasoline toward the inside of the combustion chamber 24 is provided in the vicinity of the intake port 22.

  In addition, one end of an intake pipe 28 is connected to the intake port 22. A throttle valve 30 is disposed inside the intake pipe 28.

  An air cleaner 14 is connected to the other end of the intake pipe 28.

  In the present embodiment, the other end of the intake pipe 28 is connected to the upper portion of the air cleaner 14 (the direction of arrow A in FIG. 1, the upper side in the vertical direction).

  An HC adsorbing sheet 10 that adsorbs evaporated fuel is disposed inside the air cleaner 14. Below the HC adsorption sheet 10 (in the direction of arrow B in FIG. 1), an air filter 32 for filtering the intake air is provided. An air inlet 34 for introducing external air is connected to the lower portion of the air cleaner 14 (in the direction of arrow B in FIG. 1, the lower side in the vertical direction) and below the air filter 32.

  The reason why the air filter 32 is disposed below the HC adsorbing sheet 10 is to prevent dust and the like from adhering to the HC adsorbing sheet 10 by passing air filtered by the air filter 32.

  Here, the structure of the HC adsorbing sheet 10 which is the main part of the present invention will be described in detail.

  As shown in FIG. 2B, the HC adsorbing sheet 10 of the present invention has three layers of resin plates 36 including activated carbon (adsorbed material, not shown). However, they are not simply stacked in three layers, but are stacked so that a portion close to the engine 12 has three layers, a portion far from the engine 12 has one layer, and two layers in between.

  That is, in the HC adsorbing sheet 10 of the present embodiment, the resin plate 36 is multilayered as it is closer to the engine 12, and the resin plate 36 is one layer as it is farther from the engine 12. For this reason, the amount of activated carbon is large at a portion near the engine 12 of the HC adsorbing sheet 10 and the amount of activated carbon is small at a portion far from the engine 12.

  In the HC adsorption sheet 10 of the present embodiment, three resin plates 36 are stacked, but the amount of activated carbon in the entire HC adsorption sheet 10 is the same as the amount of activated carbon in the conventional HC adsorption sheet.

  The resin plate 36 is wrapped with a non-woven fabric 38 for preventing activated carbon fragments from splashing outside, and is framed by a casing 40.

  Next, operations and effects of the evaporated fuel adsorbent 10 and the air cleaner 14 will be described.

  The gasoline injected from the injector 26 during the operation of the engine 12 flows into the combustion chamber 24 through the intake port 22. At that time, gasoline adheres to the intake system such as the intake port 22, the intake valve 20, and the piston 18.

  In this state, when the engine 12 is stopped, HC (hydrocarbon) in gasoline adhering to the intake system flows backward through the clearance of the throttle valve 30 toward the air cleaner 14. Eventually, HC enters the air cleaner 14.

    Here, since HC is heavier than air, the bottom of the intake pipe 28 slowly moves toward the air cleaner 14. For this reason, the HC concentration is not uniform inside the intake pipe 28 and the air cleaner 14, and the HC concentration near the bottom of the intake pipe 28 and the engine side (in the direction of arrow C in FIG. 2) inside the air cleaner 14 is compared. Become higher.

  Therefore, in the HC adsorbing sheet 10 of the present invention, as described above, the resin plate 36 becomes multilayer as it gets closer to the engine 12, and the resin plate 36 becomes one layer as it gets farther from the engine 12 (in the direction of arrow D in FIG. 2). As shown, the amount of activated carbon is increased in the HC adsorbing sheet 10 at a relatively high HC concentration, and the amount of activated carbon is set low in the HC adsorbing sheet 10 at a relatively low HC concentration. Can be adsorbed. As a result, as shown in FIG. 2A, unlike the HC adsorbing sheet 11 in which the three resin plates 35 are simply stacked, it is possible to prevent the pressure loss of the intake system from increasing.

  Further, as shown in FIG. 19, the activated carbon inclined sheet HC adsorbing sheet 10 (FIG. 2B) of the present invention is compared with the conventional activated carbon uniform HC adsorbing sheet (FIG. 2A), Product life can be increased by 1.5 times.

  [Second Embodiment]

  Next, an evaporative fuel adsorbent and an air cleaner according to a second embodiment of the present invention will be described.

  In addition, description of the structure which overlaps with the evaporative fuel adsorption material and air cleaner of 1st Embodiment is abbreviate | omitted suitably.

  As shown in FIG. 3, in the air cleaner 50 of this embodiment, the intake pipe 28 is connected to the lower part in the vertical direction (the direction of arrow F in FIG. 3).

  In the air cleaner 50, an HC adsorbing sheet 52 is disposed in a direction substantially perpendicular to the vertical direction.

  As shown in FIGS. 4 and 5, the HC adsorbing sheet 52 includes a lower net 56 formed with a plurality of recesses 54 that increase in depth as approaching the engine 12 side (in the direction of arrow G in FIG. 4). Yes.

  Further, activated carbon 58 (adsorbed material) that adsorbs HC is disposed in the recess 54. Therefore, as the depth of the recess 54 increases, the recess 54 contains a large amount of activated carbon 58.

  As shown in FIG. 4, an upper net 60 is attached above the lower net 56 (in the direction of arrow E in FIG. 4). The upper net 60 is welded by heat. In this manner, the outer peripheral ends of the lower net 56 and the upper net 60 and unnecessary portions where the activated carbon 58 does not enter are welded.

  For this reason, air does not pass through a portion welded by heat, such as a portion where the activated carbon 58 is not contained, so that air easily enters the recess 54 containing the activated carbon 58 accordingly. As a result, the recess 54 becomes an air passage, and the evaporated fuel and the intake air always hit the activated carbon 58. Thereby, the adsorption efficiency of HC by activated carbon 58 can be improved, and at the same time, the purge efficiency of HC adsorbed on activated carbon 58 can be improved.

  The lower net 56 and the upper net 60 are made of a thermoplastic material such as polypropylene. Although not shown, the lower net 56 and the upper net 60 have a small lattice shape so that the activated carbon 58 does not fall.

  As described above, the positioning and quantity determination of the activated carbon 58 can be facilitated by using the lower net 56 in which the recess 54 is formed to enclose the activated carbon 58.

  Further, the lower net 56 and the upper net 60 are wrapped with a non-woven fabric 62 made of polyester. Thus, even if the activated carbon 58 provided in the recess 54 is crushed and becomes fine by wrapping with the fine non-woven fabric 62, fragments of the activated carbon 58 can be captured.

  Further, after the lower net 56 and the upper net 60 are wrapped with the nonwoven fabric 62, a resin support frame 63 is attached to the outer periphery of the nonwoven fabric 62.

  Thereby, the HC adsorption sheet 52 is completed.

  In the HC adsorbing sheet 52 manufactured in this way, the amount of activated carbon increases in a portion close to the engine 12 (arrow G direction side in FIG. 4), and a portion far from the engine 12 (arrow H direction side in FIG. 4). The air cleaner 50 is disposed so that the amount of activated carbon is reduced.

  The HC adsorbing sheet 52 is disposed inside the air cleaner 50 with the support frame 63 attached. However, the HC adsorbing sheet 52 can be fixed inside the air cleaner 50 by adjusting the thickness of the support frame 63. It has become.

  On the other hand, as shown in FIG. 3, an air filter 64 is disposed above the HC adsorbing sheet 52 (in the direction of arrow E in FIG. 3).

  Further, an intake port 66 is connected to the upper portion of the air cleaner 50 in the vertical direction (in the direction of arrow E in FIG. 3) and above the air filter 64. One end portion of the intake port 66 located inside the air filter 64 extends to the engine 12 side (in the direction of arrow G in FIG. 3), that is, a portion where the activated carbon 58 content of the HC adsorption sheet 52 is large. .

  According to the HC adsorbing sheet 52 and the air cleaner 50 of the present embodiment, the evaporated fuel (HC) in the portion near the engine 12 where the HC concentration is high can be efficiently adsorbed by the activated carbon 58 having a large content. On the other hand, the evaporated fuel (HC) in the portion with a low HC concentration on the side far from the engine 12 can be efficiently adsorbed by the activated carbon 58 having a small content.

  Thus, the evaporated fuel (HC) can be efficiently adsorbed according to the concentration unevenness of the evaporated fuel (HC) without increasing the content of the activated carbon 58 in the entire HC adsorbing sheet 52. As a result, it is possible to prevent the pressure loss of the intake system from increasing.

  In particular, according to the air cleaner 50 of the present embodiment, since the intake port 66 is connected to the upper part, HC heavier than air accumulates at the bottom of the air cleaner 50, so that it is effective that HC leaks from the intake port 66 to the outside. Can be prevented.

  On the other hand, when the engine 12 is restarted after the engine 12 is stopped, since the HC has already been adsorbed on the activated carbon 58 of the HC adsorption sheet 52, the air introduced from the intake port 66 uniformly spreads the air filter 64. Passed and poured into activated carbon 58. Thereby, HC adsorbed on the activated carbon 58 is released. The separated HC is sent to the combustion chamber 24 inside the engine 12 together with the intake air.

  By the way, when the content of the activated carbon 58 is varied depending on the portion, such as the HC adsorbing sheet 52 of the present embodiment, the intake air (purge air) flows to the portion where the activated carbon content is low (the portion where the pressure loss is small). There is a tendency to go. For this reason, although the purge efficiency of the activated carbon 58 in the portion having a small activated carbon content is improved, there is a problem that the purge efficiency of the activated carbon 58 in the portion having a large activated carbon content is lowered.

Therefore, in the present invention, one end of the intake port 66 is extended to a portion of the HC adsorbing sheet 52 where the activated carbon content is high, so that the intake air can be concentrated on the activated carbon 58 where the activated carbon content is high. it can. As a result, it is possible to prevent a decrease in purge efficiency of the activated carbon 58 in a portion where the activated carbon content is large.
As described above, in the present embodiment, it is possible to improve both the HC adsorption efficiency and the purge efficiency.

  As another form of the HC adsorbing sheet 52, for example, as shown in FIG. 6A, a lower net 68 in which a recess 67 is formed in a pyramid shape may be used, and FIG. As shown in FIG. 6B, a lower net 72 in which the opening area of the indentation 70 is formed in an elliptical shape may be used. Further, as shown in FIG. 6C, the indentation 74 has a triangular cross section. The lower net 76 may be used.

  Further, the shape of the recess 54 of the lower net 56 is not limited to the above-described shape, but in particular, as shown in FIG. It is possible to prevent an uneven amount.

  [Third embodiment]

  Next, an evaporative fuel adsorbent and an air cleaner according to a third embodiment of the present invention will be described.

  In addition, description of the structure which overlaps with the evaporative fuel adsorption material and air cleaner of 1st Embodiment is abbreviate | omitted suitably.

  As shown in FIG. 7, in the air cleaner 80 of the present embodiment, the intake pipe 28 is connected to the lower part in the vertical direction (the direction of arrow J in FIG. 7).

  Further, inside the air cleaner 80, an HC adsorbing sheet 82 is arranged over the vertical direction.

  As shown in FIGS. 8 and 9, the HC adsorbing sheet 82 has a plurality of chambers 86 defined by a threshold 84 that increases in height as it approaches the lower side in the vertical direction (the direction of arrow J in FIG. 7). 88.

  In each room 86, activated carbon 90 (adsorbed material) that adsorbs HC is disposed. Therefore, as the height of the threshold 84 increases, the chamber 86 contains a large amount of activated carbon 90. Thus, the content of the activated carbon 90 arranged in each room 86 is determined by adjusting the height of the threshold 84.

  As shown in FIGS. 8 and 9, fine non-woven fabric 92 is affixed to both sides of the casing 88 so that fragments of the activated carbon 90 can be captured.

  The non-woven fabric 92 has functions on both sides of each room 86, and each room 86 is partitioned by a threshold 84 and two non-woven fabrics 92.

  As described above, the HC adsorption sheet 82 of this embodiment is completed, and the side surface of the HC adsorption sheet 82 has an inclined shape.

In the HC adsorbing sheet 82 manufactured in this way, the amount of activated carbon increases in the lower part in the vertical direction (arrow J direction side in FIG. 8), and the amount of activated carbon in the upper part in the vertical direction (arrow I direction side in FIG. 8). Is disposed inside the air cleaner 80 so as to reduce the amount of air.
On the other hand, as shown in FIG. 7, an air filter 94 is disposed on the opposite side of the intake pipe 28 with respect to the HC adsorption sheet 82.

  Further, an intake port 96 is connected to the upper side of the air cleaner 80 in the vertical direction (in the direction of arrow I in FIG. 7) and on the opposite side of the HC adsorbing sheet 82 with respect to the air filter 94. One end portion of the intake port 96 located inside the air filter 80 is curved downward in the vertical direction and extends to a portion where the activated carbon 90 content of the HC adsorbing sheet 82 is large.

  According to the evaporated fuel adsorbent 82 and the air cleaner 80 of the present embodiment, the evaporated fuel flowing backward from the engine side enters the air cleaner 80 through the intake pipe 28. Since the evaporated fuel is heavier than air, it accumulates near the bottom of the air cleaner 80.

  Therefore, like the HC adsorbing sheet 82 of the present invention, the amount of activated carbon in the vertical lower portion (the arrow J direction side in FIG. 7) of the air cleaner 80 is increased, and the vertical upper portion (the arrow I direction side in FIG. 7). By arranging so as to reduce the amount of activated carbon, it is possible to efficiently adsorb HC in a portion with a high HC concentration and to adsorb HC in a portion with a low HC concentration efficiently. That is, HC can be efficiently adsorbed corresponding to the HC concentration unevenness.

  Note that, as shown in FIG. 20, it has been found through investigation that the amount of HC adsorbed on the HC adsorbing sheet 82 increases as the air cleaner 80 is positioned on the lower side in the vertical direction.

  On the other hand, since one end portion of the intake port 96 extends to a portion where the activated carbon 90 content of the HC adsorbing sheet 82 is large, it is possible to prevent a decrease in the HC purge efficiency as in the second embodiment. Can do.

  In particular, according to the HC adsorbing sheet 82 of the present embodiment, unlike the HC adsorbing sheet 52 of the second embodiment, the upper net and the lower net are not required, so the production efficiency of the HC adsorbing sheet 82 can be improved, In addition, the manufacturing cost can be reduced.

  As in the present embodiment, the thresholds 84 may be arranged so that each room 86 has a lattice shape, but the present invention is not limited to this, and each room 98 has a row shape as shown in FIG. The threshold 100 may be arranged as follows.

  However, by arranging the holes 84 so that each room 86 has a lattice shape, partial deviation of the activated carbon 90 in the same room can be prevented as much as possible.

  [Fourth embodiment]

  Next, an evaporated fuel adsorbent and an air cleaner according to a fourth embodiment of the present invention will be described.

  In addition, description of the structure which overlaps with the evaporative fuel adsorption material and air cleaner of 1st Embodiment is abbreviate | omitted suitably.

  As shown in FIG. 11, in the air cleaner 110 of the present embodiment, the intake pipe 28 is connected to the lower part in the vertical direction (the direction of the arrow L in FIG. 11).

  An HC adsorbing sheet 112 is disposed in the air cleaner 110 so as to be inclined with respect to the vertical direction.

  As shown in FIGS. 12 and 13, the HC adsorbing sheet 112 includes a sponge 116 in which a plurality of recesses 114 are formed that become deeper as they approach the lower side in the vertical direction (the arrow L direction side in FIG. 11). Yes.

  The sponge 116 is excellent in air permeability, but is not particularly limited to the sponge 116 as long as it has excellent air permeability.

  Further, activated carbon 118 (adsorbed material) that adsorbs HC is disposed in each recess 114. Therefore, as the depth of the recess 114 increases, the recess 114 contains a large amount of activated carbon 118. In this way, by adjusting the depth of the recess 114, the content of the activated carbon 118 disposed in each recess 114 is determined.

  As shown in FIGS. 12 and 13, a fine nonwoven fabric 120 is attached to one side surface of the sponge 116 to close the dent 114 and capture the fragments of the activated carbon 118.

  Further, a casing 122 is attached to the outer periphery of the sponge 116 and the nonwoven fabric 120.

  As described above, the HC adsorption sheet 112 of the present embodiment is completed.

  In the HC adsorbing sheet 112 manufactured in this way, the amount of activated carbon increases in the lower portion in the vertical direction (arrow L direction side in FIG. 11), and the amount of activated carbon in the upper portion in the vertical direction (arrow K direction side in FIG. 11). Is arranged inside the air cleaner 110 so that there is less.

  On the other hand, as shown in FIG. 11, an air filter 124 is disposed on the opposite side of the intake pipe 28 with respect to the HC adsorption sheet 112. The air filter 124 is disposed substantially parallel to the HC adsorption sheet 112.

  Further, an intake port 126 is connected to the upper side of the air cleaner 110 in the vertical direction (in the direction of arrow K in FIG. 11) and on the opposite side of the HC adsorbing sheet 112 with respect to the air filter 124.

  One end portion of the intake port 126 located inside the air filter 110 is curved downward in the vertical direction, and extends to a portion where the activated carbon 118 content of the HC adsorption sheet 112 is large.

  According to the evaporated fuel adsorbent 112 and the air cleaner 110 of the present embodiment, the evaporated fuel that has flowed back from the engine side enters the air cleaner 110 through the intake pipe 28. Since the evaporated fuel is heavier than air, it accumulates near the bottom of the air cleaner 110.

  Therefore, like the HC adsorbing sheet 112 of the present invention, the amount of activated carbon in the vertical lower portion (the arrow L direction side in FIG. 11) of the air cleaner 110 is increased, and the vertical upper portion (the arrow K direction side in FIG. 11). By arranging so as to reduce the amount of activated carbon, it is possible to efficiently adsorb HC in a portion with a high HC concentration and to adsorb HC in a portion with a low HC concentration efficiently. That is, HC can be efficiently adsorbed corresponding to the HC concentration unevenness.

  On the other hand, since one end portion of the intake port 126 extends to a portion where the activated carbon 118 content of the HC adsorbing sheet 112 is large, it is possible to prevent a decrease in the HC purge efficiency as in the second embodiment. Can do.

In particular, according to the HC adsorbing sheet 112 of the present embodiment, the activated carbon 118 that has been crushed can be prevented from coming out of the HC adsorbing sheet 112 by the sponge 116, so that the HC adsorbing sheet 52 of the second embodiment is configured. The lower nonwoven fabric 62 becomes unnecessary. As a result, the production efficiency of the HC adsorption sheet 112 can be improved, and the production cost can be reduced.
In the second to fourth embodiments described above, one end of each of the intake ports 66, 96, 126 exists in the air cleaners 50, 80, 110, and the activated carbon of the HC adsorbing sheets 52, 82, 112. Although the form extended to the part with much content was shown, it is not restricted to these.

  For example, as shown in FIGS. 14 to 16, one end portion of the air inlet 130 is not provided inside the air cleaner 50, and as an alternative, a convex portion 132 is provided as an inner wall of the air cleaner 50. The intake air may be supplied to the portion of the HC adsorption sheet 52 where the activated carbon content is high.

  By forming such a convex portion 132, the intake air can be forcibly supplied to the portion of the HC adsorbing sheet 52 where the activated carbon content is high, so that it is possible to prevent the purge efficiency from being lowered. Further, the convex portion 132 can be easily formed by resin molding.

  As shown in FIG. 17, a resin threshold plate 144 in which a plurality of holes 142 are formed may be used for the HC adsorption sheet 140 instead of the upper net and the lower net. A fine non-woven fabric 146 is attached to the upper and lower surfaces of the threshold plate 144. Furthermore, the outer periphery of the threshold plate 144 and the nonwoven fabric 146 is fixed with a casing (not shown).

  In this case, the content of activated carbon can be adjusted by the ratio of the holes 142, that is, the opening area of the holes 142. What is necessary is just to enlarge the opening area of the hole 142 in the part which increases content of activated carbon, and to make the opening area of the hole 142 small in the part which reduces content of activated carbon.

  Further, as shown in FIG. 18, in this HC adsorbing sheet 150, the lower net 154 having a plurality of indentations 152 is used, but the depth of the indentations 152 is set to be constant, Depending on the size of the opening area of the recess 152, the content of the activated carbon disposed in each recess 152 can be adjusted. What is necessary is just to enlarge the opening area of the hollow 152 in the part which increases content of activated carbon, and makes the opening area of the hollow 152 small in the part which reduces content of activated carbon.

  The other configuration is the same as the configuration of the HC adsorption sheet 52 of the second embodiment. Moreover, although the opening of the hollow 152 is circular, it is not limited to this.

  In addition to the HC adsorbing sheet described in the corner embodiment, an HC adsorbing sheet having the following configuration may be provided inside the air cleaner.

  As shown in FIG. 21, the HC adsorbing sheet 200 (evaporated fuel adsorbing material) is disposed substantially parallel to the gravity action direction (vertical direction) inside the air cleaner (not shown).

  The HC adsorption sheet 200 includes a first resin plate 202 (sheet) including activated carbon (not shown). The first resin plate 202 is located from the ceiling surface to the bottom surface of the air cleaner 14 (see FIG. 1).

  Further, on the opposite side (arrow D direction side in FIG. 21) of the first resin plate 202 to the engine side (arrow C direction side in FIG. 21), a second resin plate 204 (not shown) including activated carbon (not shown). Sheets) are placed one on top of the other. The second resin plate 204 reaches from the bottom of the first resin plate 202 to a position approximately 2/3 of the height of the first resin plate.

  Further, on the opposite side (arrow D direction side in FIG. 21) to the engine side (arrow C direction side in FIG. 21) of the second resin plate 204, a third resin plate 206 (not shown) including activated carbon (not shown). Sheets) are placed one on top of the other. The third resin plate 206 reaches from the bottom of the first resin plate 202 to a position that is approximately half the height of the first resin plate.

  According to this HC adsorbing sheet 200, it consists of three layers of resin plates 202, 204, 206 on the vertically lower side (arrow B direction side in FIG. 21), and one layer on the vertically upper side (arrow A direction side in FIG. 21). It consists of two resin plates 202 and 204 in the middle.

  By arranging a plurality of resin plates 202, 204, and 206 having different areas so as to overlap each other in the direction of air flow, a large amount of activated carbon can be arranged on the vertically lower side inside the air cleaner 14, and HC can be efficiently used. Can be adsorbed.

  As shown in FIG. 22, the HC adsorbing sheet 210 (evaporated fuel adsorbing material) is arranged substantially parallel to the gravity action direction (vertical direction) inside the air cleaner (not shown).

  This HC adsorbing sheet 210 has a single resin plate 212 (sheet) including activated carbon (not shown), and is located on the engine side (in FIG. 22 in the direction of arrow B in FIG. 22) on the vertically lower side. It is folded back to the opposite side (arrow D direction side in FIG. 22).

  Note that the folded end 212A of the resin plate 212 reaches a substantially central region in the vertical direction inside the air cleaner.

  According to the HC adsorbing sheet 210, HC can be adsorbed efficiently as in the case of the HC adsorbing sheet 200 described above. Further, since only one resin plate 212 is provided, the HC adsorption sheet 212 can be manufactured at a low cost.

  As shown in FIG. 23A, inside the air cleaner (not shown), the HC adsorbing sheet 220 (evaporated fuel adsorbing material) is disposed substantially parallel to the gravity action direction (vertical direction).

  The HC adsorption sheet 220 has a single resin plate 222 (sheet) including activated carbon (not shown) having a relatively large pore diameter and activated carbon (not shown) having a relatively small pore diameter.

  The activated carbon having a relatively large pore diameter and the activated carbon having a relatively small pore diameter are separated in the resin plate 222, and the upper side from the substantially central portion in the vertical direction of the resin plate 222 (in the direction of arrow A in FIG. 23A). The activated carbon having a relatively small pore diameter is located in the portion 222A on the side), and the pore diameter is small in the portion 222B on the lower side (the arrow B direction side in FIG. 23A) from the substantially central portion in the vertical direction of the resin plate 222. A relatively large activated carbon is located.

  Further, the thickness of the resin plate 222 in the air flow direction is constant.

  As shown in FIG. 23 (B), the content of the activated carbon having a relatively small pore diameter or activated carbon having a relatively large pore diameter contained in the portion as the resin plate 224 is positioned on the vertically lower side. May be more.

  For this reason, the thickness of the resin plate 224 in FIG. 23B in the air flow direction increases as it is positioned on the vertically lower side (the arrow B direction side in FIG. 23B).

  According to the HC adsorbing sheet 220, an air cleaner is provided by enclosing a plurality of types of activated carbon having different pore diameters, and separating the activated carbon according to the size of the pore diameter so that the activated carbon having a relatively large pore diameter is located on the bottom side of the air cleaner. The high boiling point component of the evaporated fuel drifting on the bottom side can be efficiently adsorbed by the activated carbon having a relatively large pore diameter.

  As shown in FIGS. 24A to 24E, the HC adsorbing sheets 230, 240, 250, 260, and 270 (evaporated fuel adsorbing material) are in the gravity direction (vertical direction) inside the air cleaner (not shown). Are arranged substantially in parallel.

  As shown in FIG. 24 (A), the HC adsorbing sheet 230 has a first resin plate 232 (low-boiling component adsorbent) enclosing activated carbon (low-boiling component adsorbent) having a relatively small pore diameter. Yes. The first resin plate 232 is located from the ceiling surface to the bottom surface of the air cleaner 14.

  Further, on the opposite side (the arrow D direction side in FIG. 24A) of the first resin plate 232 to the engine side (arrow C direction side in FIG. 24A), activated carbon (high A second resin plate 234 (high-boiling component adsorbing material) including a boiling component adsorbing material) is disposed in an overlapping manner. The second resin plate 234 reaches from the bottom of the first resin plate 232 to a position that is approximately half the height of the first resin plate 232.

  Further, as shown in FIG. 24 (B), the content of activated carbon having a relatively large pore diameter contained in the second resin plate 244 of the HC adsorbing sheet 240 is set to the vertically lower side inside the air cleaner (FIG. 24 (B)). You may make it increase as it is located in the middle arrow B direction side.

  On the other hand, as shown in FIG. 24C, the content of activated carbon with a relatively small pore diameter contained in the first resin plate 252 of the HC adsorbing sheet 250 is set to the vertically lower side inside the air cleaner (FIG. 24C). You may make it increase as it is located in the middle arrow B direction side.

  Furthermore, as shown in FIG. 24D, both the content of activated carbon contained in the first resin plate 262 of the HC adsorbing sheet 260 and the content of activated carbon contained in the second resin plate 264 are determined inside the air cleaner. It may be increased as it is positioned on the vertically lower side (the arrow B direction side in FIG. 24D).

  Further, as shown in FIG. 24E, the areas of the first resin plate 272 and the second resin plate 274 of the HC adsorption sheet 270 are made the same, and the activated carbon content of the first resin plate 272 The thickness in the air flow direction of the first resin plate 272 is increased toward the vertically upper side so that the thickness increases as it is positioned on the vertically upper side (the arrow A direction side in FIG. 24 (E)) inside the air cleaner. The air flow direction of the second resin plate 274 is increased so that the content of the activated carbon of the second resin plate 274 increases as it is positioned on the vertically lower side (the arrow B direction side in FIG. 24E) inside the air cleaner. The thickness may be increased vertically downward and the two may be overlapped.

  Here, by matching the thicknesses of the first resin plate 272 and the second resin plate 274 and the rate of change thereof, they have the same volume, and when they are overlapped, the thickness in the air flow direction is constant. It becomes.

  According to each of the HC adsorbing sheets 230 described above, the low boiling point component of the evaporated fuel of the entire air cleaner can be adsorbed by the activated carbon contained in the first resin plate 232 and drifts mainly near the bottom surface of the air cleaner 14. The high boiling point component of the evaporated fuel can be adsorbed by the activated carbon included in the second resin plate 234. As a result, it is possible to reliably adsorb the evaporated fuel including the low boiling point component and the high boiling point component.

  In particular, the second resin plate 234 is overlapped on the engine side (arrow C direction side in FIG. 24A) and the opposite side (arrow D direction side in FIG. 24A) with respect to the first resin plate 232. Since it has been arranged, the activated carbon contained in the second resin plate 234 can exhibit the effect of capturing the evaporated fuel and deteriorating durability by utilizing the fact that the high-boiling component adsorption / desorption performance is excellent.

  Furthermore, by adopting the configuration of the HC adsorbing sheet 270 shown in FIG. 24 (E), the low boiling point component of the evaporated fuel that drifts a lot in the vertical upper side inside the air cleaner can be adsorbed by the first resin plate 272 efficiently. In addition, the high boiling point component of the evaporated fuel drifting in the vertically lower side inside the air cleaner can be efficiently adsorbed by the second resin plate 274.

  Further, the first resin plate 272 and the second resin plate 274 are overlapped with each other by making the thickness constant from the vertically lower side to the vertically upper side inside the air cleaner, thereby allowing the first resin plate 272 and the second resin plate 272 to overlap each other. The pressure loss of the entire resin plate 274 can be made uniform.

It is a lineblock diagram showing the state where the air cleaner provided with the evaporation fuel adsorption material concerning a 1st embodiment of the present invention was connected to the engine. It is a block diagram of the evaporative fuel adsorption material arrange | positioned at the air cleaner which concerns on 1st Embodiment of this invention. It is a block diagram of the air cleaner which concerns on 2nd Embodiment of this invention. It is an exploded view of the fuel vapor adsorbent according to the second embodiment of the present invention. It is sectional drawing of the evaporative fuel adsorbent which concerns on 2nd Embodiment of this invention. It is a perspective view of another form of the lower net which constitutes the evaporation fuel adsorption material concerning a 2nd embodiment of the present invention. It is a block diagram of the air cleaner which concerns on 3rd Embodiment of this invention. It is an exploded view of the evaporative fuel adsorbent which concerns on 3rd Embodiment of this invention. It is sectional drawing of the evaporative fuel adsorbent which concerns on 3rd Embodiment of this invention. It is a perspective view of another form of the casing which comprises the evaporative fuel adsorption material which concerns on 3rd Embodiment of this invention. It is a block diagram of the air cleaner which concerns on 4th Embodiment of this invention. It is an exploded view of the evaporative fuel adsorbent which concerns on 4th Embodiment of this invention. It is sectional drawing of the evaporative fuel adsorbent which concerns on 4th Embodiment of this invention. It is a block diagram of the air cleaner of another form of this invention. It is a block diagram of the air cleaner of another form of this invention. It is a block diagram of the air cleaner of another form of this invention. It is an exploded view of the evaporative fuel adsorbent of another form of this invention. It is an exploded view of the evaporative fuel adsorbent of another form of this invention. It is the graph which showed the durability precision of the evaporative fuel adsorption material of 1st Embodiment of this invention. It is the distribution diagram which showed the result of the degradation component investigation of a fuel vapor adsorbent. It is sectional drawing of the evaporative fuel adsorbent of another form of this invention. It is sectional drawing of the evaporative fuel adsorbent of another form of this invention. It is sectional drawing of the evaporative fuel adsorbent of another form of this invention. It is sectional drawing of the evaporative fuel adsorbent of another form of this invention.

Explanation of symbols

10, 52, 82, 112 HC adsorption sheet (evaporative fuel adsorbent)
12 engine (internal combustion engine)
14, 50, 80, 110 Air cleaner 28 Intake pipe 58, 90, 118 Activated carbon (adsorbent)
66, 96, 126 Air intake 68 Lower net (net)
88 Casing 116 Sponge (porous member)
132 Convex (inner wall)

Claims (4)

A plate-like evaporative fuel adsorbent disposed in a passage inside an air cleaner connected to an internal combustion engine and having an adsorbate that adsorbs evaporative fuel flowing back from the internal combustion engine side,
The adsorbate consists of a low-boiling component adsorbent that adsorbs a low-boiling component of the evaporated fuel and a high-boiling component adsorbent that adsorbs a high-boiling component of the evaporated fuel,
The evaporated fuel adsorbent has a low-boiling component adsorbent containing the low-boiling component adsorbent, and a high-boiling component adsorbent containing the high-boiling component adsorbent,
The low-boiling component adsorbent and the high-boiling component adsorbent are overlapped in the thickness direction, the low-boiling component adsorbent is disposed on the internal combustion engine side, and the high-boiling component adsorbent is placed vertically below the passage. An evaporative fuel adsorbent characterized by being disposed. The low-boiling-point adsorbent is thickened toward the vertically lower side of the passage, and the content of the low-boiling-point adsorbed material is increased vertically downward. Evaporative fuel adsorbent. The high-boiling component adsorbent has a thickness that is increased vertically downward in the passage, and the content of the high-boiling component adsorbed material is increased downward in the vertical direction. The evaporative fuel adsorbent described in 1. A plate-like evaporative fuel adsorbent disposed in a passage inside an air cleaner connected to an internal combustion engine and having an adsorbate that adsorbs evaporative fuel flowing back from the internal combustion engine side,
The adsorbate consists of a low-boiling component adsorbent that adsorbs a low-boiling component of the evaporated fuel and a high-boiling component adsorbent that adsorbs a high-boiling component of the evaporated fuel,
The evaporated fuel adsorbent has a low-boiling component adsorbent containing the low-boiling component adsorbent and a high-boiling component adsorbent containing the high-boiling component adsorbent,
In the passage, the low-boiling component adsorbent and the high-boiling component adsorbent having the same volume are superposed in the thickness direction by placing the low-boiling component adsorbent on the internal combustion engine side, and the low-boiling point The component adsorbent is directed vertically upward to increase the thickness, the high boiling component adsorbent is directed vertically downward to increase the thickness, and the air flow direction of the low boiling component adsorbent and the high boiling component adsorbent An evaporative fuel adsorbent characterized by having a constant total thickness.

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