JP4704127B2 - Air cleaner - Google Patents

Description

  The present invention mainly relates to an air cleaner for an engine mounted on a motorcycle.

Some motorcycle engines purify exhaust by supplying a portion of the air purified by a cleaner element as secondary air to the exhaust passage of the engine and reacting with the exhaust (see Patent Document 1).
Japanese Patent No. 2868468

  However, since the secondary air is taken out from the clean air chamber of the air cleaner and guided to the engine exhaust passage, the secondary air hose becomes long. In addition, normally, because of the layout in which the fuel tank is arranged above the cleaner case, it is not possible to secure a sufficient space for handling the secondary air hose, so the degree of freedom in designing the air cleaner is reduced. .

  The present invention has been made in view of the above-described conventional problems. A connection object to the internal space of the cleaner case, such as a secondary air hose for introducing clean air into the exhaust passage of the engine, is projected from the cleaner case. An object of the present invention is to provide an air cleaner that can be mounted in an arrangement that suppresses the above.

In order to achieve the above object, an engine of a motorcycle according to the present invention is an engine that is supported by a body frame of a motorcycle and is positioned below the main frame, and a cleaner element that purifies intake air to the engine. A cleaner case housed inside is disposed above the engine, and recesses are formed on the outer surface of the upper and front portions of the cleaner case, and clean air in the cleaner case is passed into the exhaust passage of the engine in the recess. A secondary air hose to be introduced is arranged, and a plurality of intake ducts for introducing air into the cleaner case from the front are attached to the front portion of the cleaner case side by side in the left-right direction. It is disposed between the secondary air hose, clean air input end of the upstream side in the left-right direction central portion of the upper portion of the cleaner case Communicating with the air chamber, extending to the front side upper portion of the engine while along the top and front of the outer surface of the cleaner case, on the downstream side air suction valve whose ends are disposed on the upper surface of the head cover covering an upper portion of the cylinder head It is connected.

According to this configuration, since the secondary air hose to the inner space of the cleaner case is disposed in the recess of the cleaner case, it is possible to suppress the secondary air hose from protruding from the outer surface of the cleaner case as much as possible. Therefore, it is not necessary to secure a space for arranging the secondary air hose outside the cleaner case, and the degree of freedom in designing around the air cleaner is improved. Furthermore, by disposing the secondary air hose in the recess on the outer surface of the cleaner case, it is not necessary to secure a long space for arranging the secondary air hose around the cleaner case. Further, the secondary air hose is disposed in the recess, so that the length of the secondary air hose is shortened and the efficiency of supplying the secondary air is improved as compared with the case where the secondary air hose is disposed outside the cleaner case. , Can be kept stable in the recess.

Preferably, a communication pipe that allows the secondary air hose to communicate with the cleaner case is integrally provided on the upper surface of the cleaner case and is provided inside the cap that closes the access hole for accessing the cleaner case. Yes. According to this configuration, the internal space of the cleaner case and the secondary air hose can be easily connected via the communication pipe provided in the cap. Further, the secondary air hose can be shortened by the length of the communication pipe.

The air intake port of the communication pipe is preferably located downstream of the inlet portion of the air suction duct in the flow direction of the clean air toward the air suction duct. According to this configuration, the air intake port of the communication pipe does not disturb the flow of clean air that flows into the air suction duct.

In the present invention, a recess in which an intake air temperature sensor for detecting intake air temperature is disposed is formed on the outer surface of the cleaner case . According to this configuration, when the intake air temperature sensor is attached to the outer surface of the cleaner case, the intake air temperature sensor protrudes greatly in a direction perpendicular to the outer surface, so that the protrusion from the cleaner case is effective by arranging it in the recess. Can be suppressed.

  According to the air cleaner of the present invention, since the connection object connected to the inner space of the cleaner case is arranged in the recess formed in the outer surface of the cleaner case, the protruding width of the connection object from the cleaner case is suppressed. As a result, space saving and improvement in design flexibility around the cleaner case are realized.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a side view showing a motorcycle equipped with an air cleaner according to an embodiment of the present invention. In the motorcycle shown in the figure, a front fork 2 is supported at the front end of the main frame 1 constituting the front half of the body frame FR, a front wheel 3 is provided at the lower end of the front fork 2, and a handle 4 is provided at the upper end of the front fork 2. Each is attached. A swing arm bracket (not shown) is provided at a lower end of the rear end of the main frame 1, and a front end of the swing arm 7 is pivoted on the swing arm bracket so as to be swingable up and down via a pivot shaft (not shown). It is supported. A rear wheel 8 is attached to the rear end of the swing arm 7. A seat rail 9 connected to the rear portion of the main frame 1 constitutes the rear half of the vehicle body frame FR. An engine E is attached to the lower part of the main frame 1, and a radiator 10 is disposed in front of the engine E. The motorcycle is configured to drive the rear wheel 8 via the chain 11 by the engine E and to steer the steering wheel 4.

  A rider's seat 12 and a passenger's seat 13 are supported on the seat rail 9. A fuel tank 14 is attached between the handle 4 and the rider seat 12 at the upper part of the main frame 1, that is, at the upper part of the vehicle body. An air cleaner 17 that purifies the intake air to the engine E is disposed below the fuel tank 14. The air cleaner 17 and the fuel supply device 18 of the engine E take in air that guides clean air to the engine E. They are connected by a duct 19.

  FIG. 2 is a sectional view of an engine E provided with the air cleaner 17. In the cleaner case 20 of the air cleaner 17, a case upper 20a and a case lower 20b are connected by both flange portions 20c and 20d to form a cleaner chamber therein. The cleaner case 20 is connected to a throttle body 21 of the engine E through an air suction duct 19 attached to the case lower 20b. In this example, the engine E has two cylinders and four cycles. Correspondingly, on the front side of the cleaner case 20, two intake ducts 22 (see FIG. 3) for introducing air A from diagonally forward and downward are laterally arranged. It is attached side by side. The air suction duct 19 is effective in improving the engine output and reducing the intake noise by appropriately setting the inner diameter and the total length so as to improve the intake efficiency.

A cleaner element 23 that purifies the air A is disposed in the vicinity of the downstream side (rear side) of the intake duct 22. In the cleaner case 20, the upstream side of the cleaner element 23 is an air introduction chamber 25, and the downstream side is a clean air chamber 26. The clean air CA in the clean air chamber 26 enters the fuel supply device 18 through the air suction duct 19 and the throttle body 2 thereof.
1, the fuel injected from the fuel injection valve 27 is mixed with the clean air CA whose flow rate is controlled by the throttle valve 24 to generate an air-fuel mixture. This air-fuel mixture is introduced into the combustion chamber 29 through the intake valve 28. Two air intake ducts 19 and two fuel supply devices 18 are also arranged side by side in the lateral direction.

  The air suction duct 19 is formed in a cylindrical shape by an elastic body such as rubber, and is inserted into an attachment hole of the case lower 20 b and attached to the case lower 20 b via a plate-like attachment member 30. The attachment member 30 is fixed to the case lower 20 b by fastening a plurality of bolts 31. When the air suction duct 19 is attached, an access hole 32 formed in the upper wall of the cleaner case 20 is used. The access hole 32 opens at a position facing the mounting position of the air suction duct 19 in the case upper 20a from above, and from the access hole 32, inspection in the clean air chamber 26 and attachment / detachment of the bolt 31 of the air suction duct are performed. Is possible.

  Connected to the clean air chamber 26 of the air cleaner 17 is a secondary air introduction passage 36 for purifying exhaust gas by introducing a part of the clean air CA into the exhaust passage 35 in the vicinity of the exhaust port 34. The secondary air hose 37 forming the main part of the secondary air introduction passage 36 has an upstream air introduction end communicating with the clean air chamber 26 at the center in the left-right direction at the upper part of the cleaner case 20. The upper end of the engine E extends to the upper part of the front side of the engine E along the outer surface of the front part and the downstream end thereof is connected to the air intake valve 38 disposed on the upper surface of the head cover 60 covering the upper part of the cylinder head 40. Yes. A vacuum switching valve 39 is interposed in the middle part of the secondary air hose 37. The downstream side of the air intake valve 38 in the secondary air introduction passage 36 is formed by an air injection passage 47 formed in the cylinder head 40.

  FIG. 3 is a front view showing the engine E including the air cleaner 17. Two exhaust ports 45 are formed in the front surface of the cylinder head 40 of the engine E, and the upstream ends of the exhaust pipes 41 constituting the exhaust passage 35 are connected to the exhaust ports 45, respectively. The downstream ends of both exhaust pipes 41 are connected to the muffler 43 in FIG.

  On the other hand, one air suction valve 38 to which clean air CA is fed through the secondary air hose 37 shown in FIG. 3 is provided at the center in the left-right direction of the head cover 60 and is formed inside the cylinder head 40. 2 are connected to the vicinity of each exhaust port 34 shown in FIG.

  A groove-like recess 44 shown in FIG. 3 is formed on the outer surface of the cleaner case 20 along the location where the secondary air hose 37 is provided. The secondary air hose 37 is embedded in the recess 44. The cleaner case 20 hardly protrudes outward from the upper surface and front surface of the cleaner case 20. Therefore, it is not necessary to secure a large arrangement space for the secondary air hose 37 around the upper part of the cleaner case 20. Therefore, the degree of freedom of design around the air cleaner 17 is improved. Further, since the secondary air hose 37 is disposed in the recessed portion 44 of the cleaner case 20, the length thereof is shortened compared with the case where the secondary air hose 37 is disposed outside the cleaner case 20. be able to. Thereby, the supply efficiency of clean air CA improves.

  As shown in FIG. 2, the air introduction end of the secondary air hose 37 is connected to a cap 33 that closes the access hole 32 of the cleaner case 20 so as to be freely opened and closed. As shown in FIG. 4A, the cap 33 is integrally formed with a communication pipe 48 that forms the upstream portion of the secondary air introduction passage 36 at the center in the left-right direction. The communication pipe 48 communicates the clean air chamber 26 in the cleaner case 20 with the secondary air hose 37, and has both ends opened and an upstream opening 48a and a downstream opening 48b.

  Further, as shown in FIG. 4B, the cap 33 is provided with an abutment wall 49 integrally protruding so as to surround the communication pipe 48. As shown in FIG. A projecting portion from the abutment wall 49 to the downstream side (forward) is a connecting pipe portion 48c. A fitting projection 50 shown in FIG. 4D is provided on the inner periphery of the peripheral edge of the cap 33 over the entire periphery. As shown in FIG. 4A, screw insertion holes 51 for fixing the cap 33 to the cleaner case 20 (FIG. 2) with bolts (not shown) are provided at four corners of a substantially trapezoidal shape in plan view.

As shown in FIG. 2, the cap 33 is configured such that the connecting pipe portion 48 c of the communication pipe 48 is inserted into the upstream end portion of the secondary air hose 37 so that the contact wall 49 contacts the upstream end surface of the secondary air hose 37. In the contact state, the cleaner case 20 is fitted and positioned in the fitting groove 55 around the access hole 32, and bolts are inserted into the four screw holes 51 of FIG. By fastening to 20, the cap 33 is fixed to the cleaner case 20, and the access hole 32 is closed. At this time, the communication pipe 48 has an upstream end opening (air intake port) 48a communicating with the clean air chamber 26 in the cleaner case 20, and a downstream end opening 48b communicating with the secondary air hose 37 through the connection pipe portion 48c. To do. Therefore, the clean air chamber 26 and the air hose 37 in the cleaner case 20 can be easily connected via the communication pipe 48 provided integrally with the cap 33, and the secondary air hose 37 is There is an advantage that it can be further shortened by the length of the communication pipe 48.

  In the air cleaner 17, when the exhaust passage 35 is at a lower pressure than the clean air chamber 26, the air intake valve 38 is opened and a part of the clean air CA in the clean air chamber 26 is connected to the communication pipes 48 and 2. It passes through the next air hose 37, is introduced into the vicinity of the exhaust port 34 through the air intake valve 38 and the air injection path 47, and reacts with the exhaust to purify the exhaust. The flow rate of the secondary air is adjusted by a vacuum switching valve 39 controlled by the engine controller 57. Further, the air intake port 48a of the communication pipe 48 is disposed behind the inlet portion 19a opened to the clean air chamber 26 in the air suction duct 19, that is, at a position away from the cleaner element 23. As a result of being positioned closer to the downstream side than the inlet portion 19a in the flow direction of the clean air CA toward the duct 19, the air intake port 48a is connected to the clean air CA and the communication pipe 48 flowing into the air suction duct 19. The flow of clean air CA that flows in is not disturbed. Since the engine E has two cylinders and two air suction ducts 19 are juxtaposed as shown in FIG. 3, the air intake port 48 a of the communication pipe 48 is located between the two air suction ducts 19 in the left-right direction. It is arranged in the part.

  In the above embodiment, the case where the communication pipe 48 of FIG. 4 is integrally formed with the resin cap 33 is exemplified, but a separate communication pipe may be fixed to the lower surface of the cap.

  FIG. 5 is a perspective view of the air cleaner 17 as viewed from the rear side. A recess 53 is formed on the right side of the upper portion of the cleaner case 20 at a position closer to the front than the cap 33, and an intake air temperature sensor 54 that detects the intake air temperature, which is the temperature of the clean air CA, is formed in the recess 53. Has been placed. As shown in FIG. 2, the detected temperature of the intake air temperature sensor 54 is input to the engine controller 57 and used for controlling the amount of fuel supplied from the fuel injection valve 27.

  Since the intake air temperature sensor 54 is disposed and provided in the recess 53 on the outer surface of the cleaner case 20, it is suppressed from protruding outward from the outer surface of the cleaner case 20. There is no need to secure a large installation space. In addition, the intake air temperature sensor 54 is mounted in the cleaner case 20 in a stable holding state by being disposed in the recess 53.

  The recesses 44 (FIG. 3) and 53 (FIG. 5) are not limited to the positions and shapes shown in the drawings, and can be changed as appropriate according to the type of the connected object.

1 is a side view showing a motorcycle including an air cleaner according to an embodiment of the present invention. It is a longitudinal cross-sectional view of the engine containing an air cleaner same as the above. It is a front view which shows the engine containing an air cleaner same as the above. The cap which closes the access hole of a cleaner case same as the above is shown, (a) is a top view, (b) is a front view, (c) is a CC sectional view taken on the line (a), (d) is (a). It is DD sectional view taken on the line. It is the perspective view which looked at the air cleaner same as the above from the back side.

Explanation of symbols

E Engine 17 Air cleaner 20 Cleaner case 23 Cleaner element 32 Access hole 33 Cap 35 Exhaust passage 36 Secondary air introduction passage 37 Secondary air hose (connected object)
44, 53 Recess 48 Communication pipe 48a Air intake (upstream opening)
54 Intake air temperature sensor (connected object)
CA clean air

Claims (4)

An engine that is supported by a body frame of a motorcycle and located below the main frame,
A cleaner case in which a cleaner element for purifying intake air to the engine is housed is disposed above the engine, and recesses are formed on the outer surface of the upper portion and the front portion of the cleaner case. A secondary air hose for introducing clean air in the cleaner case into the passage is disposed;
A plurality of intake ducts for introducing air into the cleaner case from the front are attached to the front portion of the cleaner case in the left-right direction, and the recess is disposed between the plurality of intake ducts,
In the secondary air hose, the upstream air introduction end communicates with the clean air chamber at the center in the left-right direction of the upper part of the cleaner case, and the front side of the engine runs along the outer surface of the upper part and the front part of the cleaner case. A motorcycle engine that extends to the top and is connected to an air intake valve disposed on the upper surface of a head cover that covers the top of the cylinder head at the downstream end. 2. The communication pipe according to claim 1, wherein the communication pipe for communicating the secondary air hose with the cleaner case is provided integrally on the inside of the cap that is provided on the upper surface of the cleaner case and closes the access hole for accessing the cleaner case. An engine for a motorcycle in which a downstream opening of the communication pipe is disposed in the recess .   The motorcycle engine according to claim 2, wherein an air intake port of the communication pipe is located downstream of an inlet portion of the air suction duct in a flow direction of the clean air toward the air suction duct.   The motorcycle engine according to claim 1, 2 or 3, further comprising a recess in the outer surface of the cleaner case in which an intake air temperature sensor for detecting an intake air temperature is disposed.

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