JP4335205B2 - V-type engine intake system - Google Patents

Description

  The present invention relates to an engine intake device capable of improving intake capacity.

  There are various types of engines mounted on motorcycles, such as V-type engines, in-line (parallel) multi-cylinder engines, and horizontally opposed engines. Among these, the V-type engine is mounted on the vehicle body by tilting a plurality of cylinders in the front-rear direction of the vehicle body so as to form a V shape in a side view. A space between a cylinder tilted forward (forward tilted cylinder) and a cylinder tilted rearward (backward tilted cylinder) is referred to as a bank space.

  In addition, the motorcycle is provided with an air cleaner (intake device) for purifying air taken in from the outside so as to be sent to the combustion chamber. From the air cleaner, an intake air flow composed of an intake pipe, a throttle body, an intake port, and the like is provided. The intake air is sent to the combustion chamber of each cylinder through the path. The intake port is formed at the head of each cylinder. In the case of a V-type engine, the intake port is often arranged on the bank space side of each cylinder. In general, an air cleaner employed in a V-type engine for a motorcycle includes a columnar filter in a case, and the columnar filter is connected coaxially to the upstream end of the intake passage. It has become.

  There are generally two types of intake flow path layouts employed in V-type engines. One is a layout in which an air cleaner is disposed above the bank space, and an intake flow path extending from the intake port extends upward to the air cleaner (see Patent Document 1), and the other is an air cleaner disposed on the side of the bank space. It is a layout in which the intake flow path that is arranged and continues from the intake port extends to the side to the air cleaner. It is known that the layout of the intake flow path affects the intake capacity of the engine and affects the engine performance.

  On the other hand, in recent years, an intake system provided with a throttle body (double throttle body) provided with two throttle valves along the direction of intake air flow is also employed as a throttle body. The double throttle body includes a main valve and a sub valve.

In general, a throttle cable is engaged with a shaft of a main valve, and the throttle cable is connected to a throttle grip provided on a steering handle. Therefore, the main valve is opened and closed by the rider operating the throttle grip. The sub-valve is driven and opened / closed by an actuator having a servo motor or the like, and the actuator is electronically controlled based on the vehicle speed, the engine speed, and the like. As a result, a suitable engine operation can be obtained by the operations of the main valve operated by the rider and the sub-valve driven by the actuator.
JP 2000-204969 A

  However, in general, the double throttle body tends to be larger in the direction of intake air flow than the throttle body having one throttle valve. Therefore, as disclosed in Patent Document 1 described above, when a double throttle body is provided in the intake passage extending in the vertical direction and a conventional air cleaner is provided at the upper end thereof, the air cleaner is positioned at a relatively high position. Therefore, the height dimension of the vehicle body becomes large. In particular, in an American type motorcycle equipped with a V-type engine having a relatively large displacement, since the engine size is originally large, there is a demand to avoid further increase in the height of the vehicle body.

  On the other hand, when a double throttle body is provided in the intake passage extending in the left-right direction, and a conventional air cleaner is provided at the side end thereof, the air cleaner is positioned on a side relatively away from the vehicle body. The left and right dimensions become large.

  In view of the improvement of the intake capacity of the engine, there is a demand to send the intake air taken into the air cleaner to the engine side as smoothly as possible. For example, in the case of an American type motorcycle, since the intake amount to the engine per cylinder is large, it is preferable to improve the intake capacity by realizing a smooth intake of intake air. Such demand exists regardless of the type of engine or throttle body.

  Therefore, an object of the present invention is to provide an air cleaner that can improve the intake capacity of an engine. It is another object of the present invention to provide an air cleaner that can effectively suppress deformation of a duct due to negative pressure generated when intake air is taken in when a duct through which intake air flows is provided.

  The present invention has been made in view of the circumstances as described above, and an engine intake device according to the present invention includes a delivery port for sending intake air taken into the internal space from the outside to the throttle body side, and the inside from the delivery port. An air cleaner box having a duct extending into the space, and an opening end surface on the intake upstream side of the duct is inclined with respect to a flow direction of the intake air at the delivery port, and the intake air in the internal space It is comprised so that it may open toward the upstream of.

  With such a configuration, the intake air in the internal space of the air cleaner box is smoothly taken into the duct from the upstream opening, so that the intake ability to the engine can be improved.

  In addition, the duct may be formed such that a part extending away from the delivery port is longer in a part that is separated from a part adjacent to the upstream side of the intake air in the internal space.

  With such a configuration, intake air in the internal space can be more easily taken into the duct.

  The duct may be configured such that an intake air flow direction in the duct is curved toward an upstream side of the intake air in the internal space.

  With such a configuration, intake air that has entered through the opening can be more smoothly guided to the throttle body.

  Further, the air cleaner box has an intake port in which a filter is provided to take in intake air from the outside into the internal space, and the end surface of the filter on the internal space side and at least a part of the opening end of the duct May be provided at substantially the same position in the flow direction of the intake air in the filter.

  The engine intake system according to the present invention includes an air cleaner box having a duct in the internal space through which intake air taken into the internal space from the outside flows, and ribs are formed on the wall of the duct. Yes.

  By adopting such a configuration, it is possible to suppress the deformation of the duct due to the negative pressure generated when intake air is taken in. In particular, the present invention is suitable for an intake device provided in an engine having a large displacement per single cylinder, which is mounted on an American type motorcycle.

  Moreover, the rib of the said duct may be each extended along the outer peripheral direction of this duct, and the flow direction of the intake air in this duct.

  By setting it as such a structure, the deformation | transformation of the duct by the generated negative pressure can be suppressed more effectively.

  Further, the duct may be integrally formed with a plurality of intake passages.

  By adopting such a configuration, since the rigidity is increased, deformation of the duct due to the negative pressure generated during intake can be suppressed. Moreover, deformation of the duct due to negative pressure can also be suppressed by integral molding. Furthermore, by integrally molding, a plurality of intake flow paths can be narrowed to reduce the size of the duct, and as a result, the intake device can be reduced in size.

  ADVANTAGE OF THE INVENTION According to this invention, the intake device which can aim at the improvement of the intake capability to an engine can be provided. Further, when a duct through which intake air flows is provided, deformation of the duct due to negative pressure generated when intake air is taken in can be effectively suppressed. This is suitable for an intake device having a relatively large amount of air).

  DESCRIPTION OF EMBODIMENTS Hereinafter, an intake device according to an embodiment of the present invention and a motorcycle V-type engine equipped with the intake device will be specifically described with reference to the drawings. FIG. 1 is a left side view of the motorcycle. A motorcycle 1 shown in FIG. 1 is an American type, and includes a frame 4 that forms a skeleton of a vehicle body between a front wheel 2 and a rear wheel 3, and an engine E is mounted in the frame 4. A change lever 4A for changing the gear ratio is provided below the left side of the engine E, and a radiator 4B supported by the frame 4 is provided in front of the engine E. A steering handle 5 operated by the rider is provided above the front wheel 2. In the following description of the present embodiment, description will be made based on directions (front and rear, left and right, and top and bottom) viewed from a rider who has boarded the motorcycle 1 shown in FIG.

  2 is a left side view of the engine E with a part cut away, and FIG. 3 is a right side view of the engine E with a part cut out. The engine E is a V-type two-cylinder four-cycle engine, and includes a cylinder 6 tilted forward (forward tilted cylinder) 6 and a cylinder tilted rearward (backward tilted cylinder) 7. It is arranged in a V shape so as to open. A crankcase 8 is provided below the cylinders 6 and 7, and an oil pan 9 is provided below the crankcase 8.

  The cylinders 6 and 7 have cylinder blocks 6A and 7A joined to the crankcase 8, cylinder heads 6B and 7B joined to the upper portions thereof, and head covers 6C and 7C joined to the upper portions thereof. . As shown in FIG. 2, the cylinder head 6B is provided with a valve operating system including an intake valve 10, an exhaust valve 11, and the like, and the cylinder 7B is similarly configured.

  A bank space 12 is formed between the cylinders 6 and 7 arranged in a V shape, and an air cleaner 13 is disposed on the right side of the bank space 12. As shown in FIG. 3, exhaust pipes 14 and 15 extend from the cylinder heads 6B and 7B. The exhaust pipes 14 and 15 extend along the engine E to the right and to the rear. Are connected to the mufflers 16 and 17.

[Main housing]
FIG. 4 is an exploded perspective view showing the main housing parts of the engine E excluding the cylinders 6 and 7. As shown in FIG. 4, the engine E includes a left crankcase 20 and a right crankcase 21 that are paired on the left and right. When the left crankcase 20 and the right crankcase 21 are closed from the left and right to form the crankcase 8, a crank chamber 30, a transmission chamber 31, an output shaft chamber 32, and a separator chamber 33 are contained in the crankcase 8. It is formed.

  The left side portion (outer side portion) of the left crankcase 20 is recessed toward the right side (center side) to form a part of the clutch chamber 34. An inner clutch cover 22 is attached to the left crankcase 20 from the left side and the peripheral portions thereof are joined to each other, and an outer clutch cover 23 is attached to the left side portion of the inner clutch cover 22. The inner clutch cover 22 is joined to the left crankcase 20, and the outer clutch cover 23 is joined to the inner clutch cover 22, whereby a clutch chamber 34 is formed inside the cover.

  A cam cover 24 is attached to a position closer to the front of the right side (outer side) of the right crankcase 21. A space between the right crankcase 21 and the cam cover 24 forms a cam chamber 35 in which a cam, a cam chain, and the like described later are stored. Further, an inner mission cover 25 is attached to a position near the right side of the right crankcase 21, and an outer mission cover 27 is attached to the right side of the inner mission cover 25.

  An oil pan 9 is attached to the lower part of the left crankcase 20 and the right crankcase 21. As a result, the oil pan 9 is located below the crank chamber 30 and the transmission chamber 31.

  Although not shown, a sealing member is interposed between the above-described members, and the members are hermetically sealed.

  FIG. 5 is a VV cross-sectional view of the engine E shown in FIG. As shown in FIG. 5, in the engine E, the crank chamber 30 is located below the cylinders 6 and 7, and a transmission chamber 31 is disposed behind the crank chamber 30.

  An output shaft chamber 32 is disposed behind the transmission chamber 31, and a right side portion of the transmission chamber 31 extends rearward along the right side portion of the output shaft chamber 32. A separator chamber 33 is disposed behind the output shaft chamber 32. Further, a clutch chamber 34 is disposed on the left side of the engine E and on the left side of the crank chamber 30 and the transmission chamber 31.

  Gas can flow between the crank chamber 30 and the clutch chamber 34, between the clutch chamber 34 and the output shaft chamber 32, and between the output shaft chamber 32 and the separator chamber 33. Yes. Therefore, blow-by gas generated in the crank chamber 30 can reach the separator chamber 33 from the crank chamber 30 via the clutch chamber 34 and the output shaft chamber 32.

  The crank chamber 30, the transmission chamber 31, the output shaft chamber 32, the separator chamber 33, and the clutch chamber 34 are integrally formed by a crank case 8 formed by closing the left crank case 20 and the right crank case 21 together. . Accordingly, the number of parts can be reduced as compared with the case where each of the chambers 30 to 34 is configured separately, so that the engine weight and assembly man-hours can also be reduced. Further, the engine E can be made compact.

[Power transmission structure]
The left crankcase 10 and the right crankcase 11 described above are provided with a plurality of shafts for transmitting the power of the engine E. As shown in FIG. 5, a crankshaft 40 is accommodated in the crank chamber 30. Each of the left crankcase 20 and the right crankcase 21 is provided with a bearing portion 41, and the crankshaft 40 is rotatably supported by the bearing portion 41 so that the shaft core faces in the left-right direction. A piston 44 is connected to the crankpin 42 of the crankshaft 40 via a connecting rod 43. The piston 44 slides substantially vertically in the cylinder blocks 6A and 7A.

  The right end portion of the crankshaft 40 penetrates the right crankcase 21 and protrudes into the cam chamber 35, and is connected to cam sprockets 45 and 46 (see also FIG. 3) via a chain. Further, the right end portion of the crankshaft 40 is also connected to balancer shafts 47 and 48 (see FIG. 3) disposed before and after the crankshaft 40 via a chain. The balancer shafts 47 and 48 rotate as the crankshaft 40 rotates.

  As shown in FIG. 5, a partition wall 49 formed in the left crankcase 20 is provided between the crank chamber 30 and the clutch chamber 34 to partition both chambers. The bearing 41 described above is provided through the partition wall 49. The left end portion of the crankshaft 40 penetrates the bearing portion 41 provided in the partition wall 49 and protrudes into the clutch chamber 34, and a generator 50 for power generation is provided at the left end portion.

  In the transmission chamber 31, a main shaft 51 and a counter shaft 52 are rotatably supported so that the shaft core is parallel to the crankshaft 40. The left end portion of the main shaft 51 passes through a partition wall 54 that partitions the transmission chamber 31 and the clutch chamber 34 and protrudes into the clutch chamber 34, and a clutch 55 is provided at the left end portion. The crankshaft 40 and the main shaft 51 are connected to each other via sprockets 56 and 57 and a chain 58 in the clutch chamber 34.

  The main shaft 51 and the counter shaft 52 are provided with a transmission 61 including a plurality of gears 60 having different diameters. When the operator operates the change lever 4A (see FIG. 1), the predetermined gear 60 of the main shaft 51 and the predetermined gear 60 of the counter shaft 52 are engaged with each other.

  An output shaft 63 is rotatably supported in the output shaft chamber 32 such that the axis is parallel to the counter shaft 52. The right end portion of the output shaft 63 projects from the output shaft chamber 32 to the right rear portion in the transmission chamber 31. The right end portion of the output shaft 63 and the right end portion of the counter shaft 52 are provided with gears that mesh with each other, and the rotational force of the counter shaft 52 is transmitted to the output shaft 63 via the gears.

  The left end portion of the output shaft 63 protrudes from the output shaft chamber 32 to the left side of the left crankcase 20, and a pulley 64 is provided at the left end portion. A belt (not shown) is stretched between the pulley 64 and the shaft of the rear wheel 3 (see FIG. 1) of the motorcycle 1, and the rotational force of the output shaft 63 is transmitted to the rear wheel 3. ing.

[Intake system]
FIG. 6 is a plan view showing a state when the periphery of the cylinder heads 6B and 7B of the engine E shown in FIG. 3 is looked down from above. As shown in FIG. 6, the cylinders 6 and 7 are arranged to be shifted from each other to the left and right with respect to a center line 70 extending in the front-rear direction through the substantially left and right center positions of the motorcycle 1. The cylinder 6 positioned is arranged on the right side of the center line 70 with respect to the cylinder 7 positioned rearward.

  In the cylinder heads 6B and 7B, intake ports 73 and 74 forming part of the intake passages 71 and 72 are provided on the bank space 12 side. An intake port 73 provided in the cylinder head 6B communicates between a combustion chamber 75 formed in the cylinder 6 and the outside of the cylinder 6, and an upstream end thereof is located on the right rear side in the bank space 12 ( It opens toward the direction (substantially 45 ° with respect to the center line 70). The intake port 74 provided in the cylinder head 7B communicates between the combustion chamber 76 formed in the cylinder 7 and the outside of the cylinder 7, and its upstream end is located on the right front side in the bank space 12 ( It opens toward the direction (substantially 45 ° with respect to the center line 70).

  In the bank space 12, an intake pipe 77 that forms another part of the intake passages 71, 72 leading to the intake ports 73, 74 is disposed on the right side of each intake port 73, 74. The downstream end is connected to the intake ports 73 and 74. A throttle body 80 is disposed on the right side of the intake pipe 77, and an upstream end portion of the intake pipe 77 is connected to the throttle body 80. The throttle body 80 is connected to the intake flow passage 71, Still another part of 72 is formed. Further, an air cleaner 13 is disposed on the upstream side of the throttle body 80, and is connected to a delivery duct 113 (see FIG. 11), which will be described later, provided in the air cleaner 13.

  As shown in FIG. 7, the throttle body 80 is a so-called double throttle body, and a main valve 82 that is opened and closed by a throttle cable 81 and a sub valve 84 that is opened and closed by an actuator 83 having a built-in servo motor (not shown). And. The main valve 82 and the sub valve 84 are disposed along the intake flow paths 71 and 72 in the throttle body 80, and the main valve 82 is located on the downstream side of the sub valve 84.

  Further, the throttle body 80 is provided with valve shafts 85 and 86 so that the axis is along the longitudinal direction. The main valve 82 and the sub valve 84 are opened and closed as the valve shafts 85 and 86 rotate around the axis.

  The rear end portion of the valve shaft 85 of the main valve 82 is provided with an urging spring 87 that urges the valve shaft 85 in one direction around its axis and an engaging portion 88 that rotates together with the valve shaft 85. ing. One end of a throttle cable 81 is connected to the engaging portion 88. The throttle cable 81 is disposed forward from the engaging portion 88, bypassing the upper portion of the front head cover 6C, and the other end is a steering handle. 5 (see FIG. 1) is connected to a throttle grip (not shown).

  Accordingly, when the rider operates the throttle grip while the engine E is in operation, the main valve is opened by the throttle cable 81 and the intake air amount increases. On the other hand, when the rider does not operate the throttle grip, the valve is closed by the action of the urging spring 87 and the intake air amount is limited, and the engine E enters the idling state.

  An actuator 83 is provided at the front end portion of the valve shaft 86 of the sub valve 84, and the actuator 83 is connected to a computer (not shown) mounted on the motorcycle 1 through a signal line. The computer acquires information on the engine speed, the opening degree of the main valve 82, and the like from a sensor (not shown), and transmits an instruction signal to the actuator 83 based on these information. The actuator 83 adjusts the opening degree of the sub valve 84 based on the instruction signal received via the signal line.

  As described above, by providing the V-type engine E with the double throttle body 80, it is possible to appropriately adjust the intake air amount, so that a more preferable engine operation can be obtained. Further, as described above, since the engaging portion 88 to which one end of the throttle cable 81 is engaged is provided in the rear portion of the throttle body 80, the throttle cable 81 is easily bypassed above the head cover 6C of the cylinder 6 positioned in front. It can be extended forward (see also FIG. 3). Furthermore, since the actuator 83 is disposed at the front portion of the throttle body 80, the heat generated from the built-in motor can be efficiently released and cooled by the wind received during traveling.

  In the present embodiment, the configuration in which the actuator 83 is disposed at the front portion of the throttle body 80 as described above has been described, but conversely, the actuator may be disposed at the rear portion of the throttle body 80. As shown in FIG. 6, in the configuration of the cylinders 6 and 7 shown in the present embodiment, a larger space is secured on the rear side of the throttle body 80 than on the front side. Therefore, when an actuator is arranged at the rear part of the throttle body 80, a wider arrangement space can be utilized, and a wider design freedom of a device including the actuator that drives the sub valve 84 can be secured.

  As shown in FIG. 6, the intake flow paths 71 and 72 according to the present embodiment are formed by a duct 113 provided in the intake ports 73 and 74, the intake pipe 77, the throttle body 80, and the air cleaner 13 in order from the downstream side. Yes. The intake ports 73 and 74 are formed so that most of the intake channels 71 and 72 are located in the same substantially horizontal plane, and the intake pipe 77 and the throttle body 80 are arranged in the same manner. In addition, as shown in FIG. 6, the intake flow path 71 and the intake flow path 72 are not merged. In this case, since interference between the intake air supplied to each of the cylinders 6 and 7 can be suppressed, stable engine operation characteristics can be obtained in a wide rotation speed range from low rotation to high rotation.

  Further, as shown in FIG. 6, the intake flow path 71 is on the way from the combustion chamber 75 to the bank space 12 side and then to the upstream side and in the vicinity of the combustion chamber 75 (in FIG. 6, the intake port 73 and the intake pipe). 77), and is curved to extend to the right side of the bank space 12. Further, the radius of curvature 71R at the portion having the smallest curvature radius (intake pipe 77 in FIG. 6) in the intake passage 71 is configured to be larger than the diameter 71r of the intake passage 71.

  Similarly, the intake flow path 72 is curved in the vicinity of the combustion chamber 76 (intake port 74 and intake pipe 77 in FIG. 6) on the way from the combustion chamber 76 toward the bank space 12 and then to the upstream side. In addition, the shape extends to the right side of the bank space 12. As with the intake flow path 71, the intake flow path 72 is also configured such that the radius of curvature at the portion with the smallest curvature radius is larger than the diameter of the flow path.

  Since the intake flow paths 71 and 72 have such a configuration, the resistance of the intake air flowing through the flow path is suppressed, and the intake efficiency of the engine E is improved. In particular, since the intake ports 73 and 74 are opened so as to form approximately 45 ° with respect to the center line 70, a relatively large radius of curvature as described above can be ensured in the intake passages 71 and 72. .

  In the present embodiment, as described above, the configuration in which the intake channels 71 and 72 are arranged in front and rear is described. However, the configuration in which the intake channels 71 and 72 are arranged in parallel vertically may be employed. In this case, since the valve shafts 85 and 86 are provided along the vertical direction, the throttle cable 81 can be easily disposed around the cylinder 6 by disposing the engaging portion 88 on the upper portion of the throttle body 80. Can do.

  On the other hand, as shown in FIG. 6, an exhaust port 91 that forms a part of the exhaust passage 90 is provided at the front of the cylinder head 6 </ b> B, and the exhaust port 91 is provided outside the combustion chamber 75 and the cylinder 6. Are communicated with each other by an exhaust passage 90. The exhaust port 91 is curved from the combustion chamber 75 and extends slightly to the right while curving forward. Accordingly, the downstream end of the exhaust port 91 opens toward the front right side. The downstream end of the exhaust port 91 is connected to the upstream end of the exhaust pipe 14 that forms another part of the exhaust flow path 90. The exhaust pipe 14 extends from the downstream end of the exhaust port 91 toward the front right side, and then curves and extends downward as shown in FIG. It is extended toward.

  Further, an exhaust port 93 that forms a part of the exhaust passage 92 is provided at the rear of the cylinder head 7B. The exhaust port 93 is provided between the combustion chamber 76 and the outside of the cylinder 7. 92 to communicate with each other. The exhaust port 93 is curved and extends slightly to the right while going backward from the combustion chamber 76. Accordingly, the downstream end of the exhaust port 93 opens toward the rear right side. The downstream end of the exhaust port 93 is connected to the upstream end of the exhaust pipe 15 that forms another part of the exhaust passage 92. The exhaust pipe 15 extends from the downstream end portion of the exhaust port 93 toward the rear right side, and then curves and extends downward as shown in FIG. It is extended toward.

  Since the exhaust port 91 and the exhaust pipe 14 are configured as described above, the exhaust flow path 90 and the intake flow path 71 are located with respect to the combustion chamber 75 particularly in the vicinity of the combustion chamber 75 as shown in FIG. It has a substantially symmetrical shape. Similarly, when the exhaust port 93 and the exhaust pipe 15 are configured as described above, particularly in the vicinity of the combustion chamber 76, the exhaust passage 92 and the intake passage 72 are substantially symmetrical with respect to the combustion chamber 76. It has a unique shape. Such a configuration has an advantage with respect to the combustion efficiency in the combustion chambers 75, 76.

  That is, as shown in FIG. 8, the intake air flowing through the curved intake passage 71 becomes a mixture by supplying fuel in the intake passage 71, and the intake valve 10 (see FIG. 2) is opened and combusted. It flows into the chamber 75 and flows in a vortex in the combustion chamber 75 (see arrow 95 shown by a solid line in FIG. 7). The air-fuel mixture flowing in the combustion chamber 75 is ignited by a spark emitted from a spark plug (not shown), burns, and pushes down the piston 44 (see FIG. 5).

  After that, the exhaust gas remaining in the combustion chamber 75 flows in a slightly swirl due to inertia, so that when the exhaust valve 11 (see FIG. 2) is opened as the piston 44 (see FIG. 5) rises, the exhaust gas is smooth. To the exhaust port 91 and discharged through the exhaust passage 90 (see arrow 96 shown by a broken line in FIG. 7). Thus, since the exhaust after combustion can be discharged efficiently, the exhaust remaining in the combustion chamber 75 can be reduced, and the combustion efficiency can be improved.

  Similarly, in the intake passage 72, the combustion chamber 76, and the exhaust passage 93 (see FIG. 6) in the cylinder 7, exhaust gas after combustion can be efficiently discharged and remains in the combustion chamber 76. Exhaust can be reduced and combustion efficiency can be improved.

[Air cleaner]
FIG. 9 is a cross-sectional view of the air cleaner 13 shown in FIG. 6 taken along the line IX-IX, and FIG. 10 is an exploded view of the air cleaner 13. As shown in FIGS. 9 and 10, the air cleaner 13 includes a main body portion 100, a filter portion 101, and a cover portion 102. By combining these three parts, the first chamber (dirty space) as shown in FIG. 104 and a second chamber (clean space) 105 are formed. The first chamber 104 and the second chamber 105 are partitioned by a plate-like filter 106 provided in the filter unit 101, and air can flow between the two chambers through the filter 106.

  Further, as shown in FIG. 10, each of the main body portion 100, the filter portion 101, and the cover portion 102 is provided with a plurality of bolt fastening holes 107 whose axial centers coincide with each other in the combined state. The two parts are fixed by screwing bolts 108 into the corresponding bolt fastening holes 107.

  Hereinafter, the configuration of the air cleaner 13 will be described in more detail. 11 is a side view of the main body 100, and FIG. 12 is a view of the main body 100 taken along the arrow XII shown in FIG. As shown in FIGS. 11 and 12, the main body 100 has a concave portion 110 that is recessed toward one side (vehicle body center side), and the concave portion 110 forms the above-described first chamber 104 (see FIG. 9). . Intake walls 111 and 112 for taking in air from the outside are provided on the back wall and the bottom wall of the recess 110, respectively, so as to reduce intake resistance. In addition, both the intake ducts 111 and 112 have the outer opening end opened downward and the inner opening end opened toward the other side (the vehicle body right side). Accordingly, falling raindrops, airborne dust, and the like are unlikely to enter the first chamber 104 (see FIG. 9) along with air, and the outside air sucked from below can be smoothly guided into the first chamber 104. It has become.

  A delivery duct 113 that sends out the air in the second chamber 105 (see FIG. 9) to the outside is provided at the upper part of the main body 100. As shown in FIG. 12, the delivery duct 113 is configured such that two juxtaposed tubes are integrally formed of a synthetic resin having flexibility, and the opening ends on the outer sides of the respective tubes are delivery ports 114 and 115. Is made. On one side end face of the delivery duct 113, a protruding lip (seal part) 113A integrally formed of synthetic resin is provided so as to surround the periphery of the delivery outlets 114 and 115 (see also FIG. 9). . A plurality of screw holes 113 </ b> B for connecting the air cleaner 13 to the throttle body 80 are provided around the delivery ports 114 and 115.

  FIG. 13 is an enlarged cross-sectional view of a joint portion between the air cleaner 13 and the throttle body 80. As shown in FIG. 13, when the air cleaner 13 and the throttle body 80 are joined, the lip 113 </ b> A provided at the peripheral edge of the delivery ports 114 and 115 abuts on the flat joining surface of the throttle body 80. In this state, the air cleaner 13 and the throttle body 80 are bolted through the bolt hole 113B (see FIG. 12). As a result, since the lip 113A is made of a synthetic resin as described above, the joint between the air cleaner 13 and the throttle body 80 can be airtightly joined. Further, it is not necessary to separately prepare a sealing member such as an O-ring (O-ring), and a connection holder or the like is not necessary.

  Further, as shown in FIG. 9, the cover portion 102 is recessed to the other side (right side of the vehicle body) and the inner surface is curved, and the delivery duct 113 is formed in the second chamber 105 in the shape of the inner surface of the cover portion 102. Is curved to extend along the lower right side. Therefore, the air flowing into the second chamber 105 flows along the inner surface shape of the cover portion 102 and is smoothly guided into the delivery duct 113. Further, as already described, the delivery duct 113 forms part of the upstream side of the intake flow paths 71 and 72 (see FIG. 6) according to the present embodiment. Therefore, since the delivery duct 113 is extended into the second chamber 105, the intake passages 71 and 72 are secured relatively long.

  As shown in FIG. 12, a secondary air supply pipe connecting portion 120 having a secondary air supply port and communicating with the second chamber 105 (see FIG. 9) is provided at the upper portion of the main body portion 100. A secondary air supply pipe 121 is connected to the secondary air supply pipe connecting portion 120. As shown in FIG. 14, the secondary air supply pipe 121 is branched into two branch pipes 122 and 123 on the way, and the branch pipe 122 extends forward and is connected to the upper front portion of the cylinder 6 to be connected to the cylinder head 6B. The branch pipe 123 extends rearward, is connected to the upper rear portion of the cylinder 7 and communicates with the exhaust flow path 92 at the cylinder head 7B. In addition, a check valve 124 is provided at a branch point of the secondary air supply pipe 121 to allow the air flow from the secondary air supply pipe 121 to the branch pipes 122 and 123 and restrict the reverse flow. Yes.

  Accordingly, as shown in FIG. 14, a part of the air in the air cleaner 13 flows out from the second chamber 105 through the secondary air supply pipe 121 and flows through the branch pipes 122 and 123 through the check valve 124. Subsequently, the air flows from the branch pipes 122 and 123 to the exhaust flow paths 90 and 92 and is mixed with the exhaust gas and flows through the exhaust pipes 14 and 15. Such an air flow is generated by the action of negative pressure in the exhaust passages 90 and 92.

  As shown in FIG. 9, the bottom of the second chamber 105 forms a water reservoir (catch tank) 125 that stores the water that has entered the second chamber 105. A water storage amount confirmation hole (viewing hole, water amount display portion) 126 that communicates the water storage portion 125 below the second chamber 105 and the left outside of the main body portion 100 is provided at a position below the recess 110 in the main body portion 100. (See also FIG. 11). A translucent rubber cap 127 is detachably placed on the outer opening end of the water storage amount confirmation hole 126. Accordingly, the amount of water accumulated in the water storage unit 125 can be visually recognized through the rubber cap 127, and the accumulated water can be discharged by removing the rubber cap 127.

  When the air cleaner 13 is attached to the right side of the engine E as shown in FIG. 3, the water storage part 125, the water storage amount confirmation hole 126, and the rubber cap 127 shown in FIG. No exposure to the right side of E. Therefore, the motorcycle 1 equipped with such an engine E does not lose its aesthetic appearance due to the exposure of the water storage part 125, the water storage amount confirmation hole 126, and the rubber cap 127. On the other hand, as shown in FIG. 2, the rubber cap 127 can be visually recognized from the left side of the engine E through the bank space 12 of the engine E. Therefore, there is no problem in confirming the water amount.

  As shown in FIG. 12, a breather pipe connection hole 130 that communicates the second chamber 105 (see FIG. 9) with the left outside of the main body 100 is provided below the recess 110 in the main body 100. The breather pipe connection hole 130 is located below the filter 106 when the main body 100 and the filter 101 are joined. As shown in FIG. 15, one end of a breather pipe 131 is connected to the breather pipe connection hole 130, and the other end is connected to the upper surface of the rear part of the crankcase 8, so that the separator chamber 33 in the crankcase 8 (FIG. 5). (See).

  As already described, the blow-by gas generated in the crank chamber 30 shown in FIG. 5 reaches the separator chamber 33 from the crank chamber 30 via the clutch chamber 34 and the output shaft chamber 32 (see also FIG. 15). ). The blow-by gas in the separator chamber 33 flows through the breather pipe 131 as shown in FIG. 15 and flows into the second chamber 105 of the air cleaner 13 through the breather pipe connection hole 130. The blow-by gas that has flowed into the second chamber 105 is carried along with the intake air through the delivery duct 113 and is again combusted in the combustion chambers 75 and 76 (see FIG. 6).

  As shown in FIG. 15, the breather pipe 131 extends downward from the upper surface of the rear part of the engine E through the cylinder 7 downward in the bank space 12. As shown in FIG. 1, the rear upper surface of the engine E and the upper part of the cylinder 7 are not exposed to the outside, and the breather pipe 131 is not exposed to the outside. Therefore, the American type motorcycle 1 has an advantageous piping configuration without impairing the aesthetic appearance.

  In addition, the blow-by gas is cooled in the process of flowing through the breather pipe 131, liquefied oil is separated, and the separated oil may flow into the air cleaner 13. In the air cleaner 13 described above, the breather pipe connection hole 130 is provided in the lower portion of the main body 100, and therefore, when the liquefied oil flows into the second chamber 105, it is possible to prevent the air cleaner 13 from adhering to the filter 106. it can. Moreover, since the breather pipe | tube 131 is extended upwards from the breather pipe | tube connection hole 130 as mentioned above, the water and oil which accumulated in the water storage part 125 do not flow backward to the separator chamber 33 (refer FIG. 5). Further, the blow-by gas that has flowed in through the breather pipe connection hole 130 is diluted by the air that has flowed in through the filter 106 before reaching the delivery duct 113. Accordingly, it is possible to suppress blow-by gas having a relatively high oil concentration from being sent to the combustion chamber.

  As shown in FIG. 9, an intake air temperature sensor 132 is attached to the recess 110 of the main body 100. More specifically, the intake air temperature sensor 132 is inserted into a mounting hole 133 that penetrates the main body 100 and the intake duct 112, and is provided with the tip exposed in the intake duct 112 (FIG. 12). See also). The intake air temperature sensor 132 detects the temperature of the air flowing through the first chamber 104, and a signal related to the detected temperature is sent to a computer (not shown) mounted on the motorcycle 1 and used for operation control of the engine E. Is done. In the intake duct 112, the intake air flow velocity is relatively large and the stagnation is small, so that the accurate intake air temperature can be detected.

  In the case of an engine such as a large American motorcycle, the displacement of each cylinder 6 and 7 is relatively large with respect to the capacity of the air cleaner 13 (the combined capacity of the first chamber 104 and the second chamber 105). The air taken into the air cleaner 13 is taken into the combustion chambers 75 and 76 immediately. Therefore, it is easier to secure the calculation time and control time in the computer if the temperature is detected on the upstream side of the intake as much as possible. As described above, by providing the intake air temperature sensor 132 in the intake duct 112 located on the most upstream side of the intake air in the air cleaner 13, the calculation time and the control time can be secured, and the detected temperature information can be controlled more reliably. It can be used for.

  FIG. 16 is a diagram illustrating a configuration of the filter unit 101. As shown in FIG. 16, the filter unit 101 includes a frame 140 and a plate-like filter 106. A relatively large upper opening 141 and a relatively small lower opening 142 are formed in the frame 140, and the filter 106 is disposed between the upper opening 141 and the lower opening 142. As shown in FIG. 9, the filter 106 has a sheet-like filter material folded back and forth several times in a bellows shape to form a plate shape as a whole. Further, as shown in FIG. 16, a metal thin plate 143 having a mesh shape is formed on the surface of the filter 106 on the second chamber 105 side.

  The frame 140 is provided with a first seal portion 144 at the periphery thereof. When the main body part 100, the filter part 101, and the cover part 102 shown in FIG. 10 are fastened by the bolts 108, the first seal part 144 has a peripheral part and a cover part of the main body part 100 as shown in FIG. It is interposed between the peripheral part of 102, and joins both airtightly. As a result, the main body 100 and the cover 102 are joined in an airtight manner.

  As shown in FIG. 16, the frame 140 is provided with a second seal portion 145 (indicated by a two-dot chain line in FIG. 15) on the outer peripheral portion of the filter 106 and on the side facing the main body portion 100. . As shown in FIG. 9, the second seal portion 145 hermetically joins between the opening peripheral portion of the recess 110 included in the main body portion 100 and the outer peripheral portion of the filter 106. As a result, by the first seal portion 144 and the second seal portion 145, the joint portion between the main body portion 100 and the cover portion 102, the joint portion between the upper opening 141 and the main body portion 100, and the joint portion between the filter 106 and the main body portion 100. And each of the joining location of the lower opening 142 and the main-body part 100 is airtightly joined.

  As described above, since the frame 140 constituting the filter unit 101 includes the first seal portion 144 and the second seal portion 145, when the main body portion 100, the filter portion 101, and the cover portion 102 are joined to each other, the seals are separately sealed. No parts are required. In addition, since the above three parts are fastened by bolts 108, the parts are hermetically joined, so that the workability at the time of assembly is also good.

  Further, the filter unit 101 is not accommodated in the main body unit 100, and the outer shape of the filter unit 101 is set so that the first seal portion 144 on the peripheral edge of the filter unit 101 seals between the main body unit 100 and the cover unit 102. It matches with the shape of the joining part of the main-body part 100 and the cover part 102 (refer FIG. 10). Therefore, in the filter part 101, the 1st seal | sticker part 144 is provided in the outermost edge part, The surface area of the filter 106 provided in the inner side can be ensured comparatively large.

  As shown in FIG. 9, when the filter unit 101 is joined to the main body 100, the delivery duct 113 provided in the main body 100 protrudes into the second chamber 105 through the upper opening 141 and supplies secondary air. The pipe connecting portion 120 is also communicated with the second chamber 105 through the upper opening 141. Similarly, when the filter unit 101 is joined to the main body unit 100, the water storage amount confirmation hole 126 and the breather pipe connection hole 130 provided in the main body unit 100 are moved to the second chamber 105 side through the lower opening 142 of the filter unit 101. The water storage amount confirmation hole 126 is exposed and communicates with the water storage part 125 (see FIG. 9) already described.

  When the air cleaner 13 having such a configuration is applied to the motorcycle 1, a plate-like filter 106 is used, and the first chamber 104 is disposed below the throttle body 80 as shown in FIG. The protrusion dimension 150 (refer FIG. 6) to the direction can be suppressed. In addition, since the duct 113 forming part of the intake flow paths 71 and 72 is extended into the air cleaner 13, the flow path length can be secured relatively long, and the intake efficiency can be improved.

  The intake device according to the present invention can be applied to an intake device for an engine mounted on a motorcycle, a four-wheel buggy or the like.

1 is a left side view of a motorcycle equipped with an engine according to an embodiment of the present invention. FIG. 2 is a left side view of the engine shown in FIG. 1 with a part cut away. FIG. 2 is a right side view of the engine shown in FIG. 1 with a part cut away. It is a disassembled perspective view which shows the main housing components of the engine except a cylinder. FIG. 5 is a VV cross-sectional view of the engine shown in FIG. 2. FIG. 4 is a plan view showing the periphery of a cylinder head of the engine shown in FIG. 3. FIG. 7 is a partial cross-sectional plan view showing a configuration of a throttle body in the engine shown in FIG. 6. FIG. 7 is a partial cross-sectional plan view showing the flow of intake air and exhaust gas in the engine shown in FIG. 6. It is IX-IX arrow sectional drawing of the air cleaner shown in FIG. FIG. 10 is an exploded view of the air cleaner shown in FIG. 9. It is a side view of the main-body part which comprises the air cleaner shown in FIG. It is a XII arrow directional view of the main-body part shown in FIG. It is an expanded sectional view of the joined part of an air cleaner and a throttle body. FIG. 2 is a side view of the engine showing a flow of secondary air in the engine shown in FIG. 1. FIG. 2 is a side view of the engine showing a flow of blow-by gas in the engine shown in FIG. 1. It is drawing which shows the filter part which comprises the air cleaner shown in FIG.

Explanation of symbols

1 Motorcycle 13 Air cleaner (intake device)
80 Throttle body 104 First chamber 105 Second chamber 106 Filter 113 Delivery ducts 114, 115 Delivery port E Engine

Claims (7)

An intake device that is mounted on a motorcycle body and disposed outside the bank space of a V-type engine having a bank space between a forward tilt cylinder and a rear tilt cylinder,
An air cleaner that is disposed outside the bank space and has a delivery port for sending intake air taken into the internal space from the outside through the intake port to the throttle body side, and a duct extending from the delivery port into the internal space. With a box,
The delivery port is disposed above the intake port, and the air flow direction at the delivery port and the air flow direction at the intake port are set substantially parallel and opposite to each other. ,
The opening end surface on the intake upstream side of the duct is configured to incline with respect to the flow direction of intake air at the delivery port and open downward toward the upstream side of intake air in the internal space. V-type engine intake system characterized by this. The air cleaner box is configured so that intake air flows along an arc-shaped flow route from the intake port to the upper delivery port in the internal space, and the duct is configured to have the arc-shaped flow path . 2. The V-type engine according to claim 1, wherein an extension dimension from the delivery port is longer in a radially outer portion than in a radially central portion of the flow route. Intake device. The duct is configured such that an intake flow direction in the duct is curved from the opening end surface to the delivery port so as to follow the circular arc flow route. Item 3. The V-type engine intake device according to Item 2. The air cleaner box has an intake port in which a filter is provided to take in intake air from the outside into the internal space, and an end surface of the filter on the internal space side and at least a part of the opening end of the duct are The intake device for a V-type engine according to any one of claims 1 to 3, wherein the intake device is provided at substantially the same position in the flow direction of intake air in the filter. 4. The intake device for a V-type engine according to claim 1, wherein a rib is formed on a wall portion of the duct. 6. The intake device for a V-type engine according to claim 5, wherein the ribs of the duct are respectively extended along the outer circumferential direction of the duct and the flow direction of the intake air in the duct. . 7. The V-type engine intake device according to claim 5, wherein the duct has a plurality of intake passages and is integrally formed.

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