JP7266146B2 - Intake purification device - Google Patents

Description

The present invention relates to an intake air purification device.

2. Description of the Related Art Conventionally, there is known an intake air purifying device that includes an air cleaner box whose interior is partitioned into a dirty side and a clean side by an air cleaner element, and a connecting pipe through which intake air flows from the clean side toward the engine side (for example, , see Patent Document 1). In a saddle type vehicle, the intake purification device has various shapes and locations depending on the type of vehicle.

WO2019/142279

By the way, in the intake air purifier, it is difficult for intake air to flow from the clean side to the engine side depending on the shape of the inside of the air cleaner box and the position of the upstream end of the connecting pipe. For example, when an intake purification device is installed in a saddle-riding type vehicle, if the intake efficiency decreases, the response of the engine will be delayed especially in the low speed range of the engine, and the drivability will be impaired.
SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances described above, and it is an object of the present invention to provide an intake air purifying device that facilitates the flow of intake air through a connecting pipe, thereby improving the efficiency of intake air.

This specification includes all the contents of Japanese Patent Application/Japanese Patent Application No. 2020-064279 filed on March 31, 2020.
The intake purification device includes an air cleaner box (235, 435) whose interior is partitioned into a dirty side (247D, 447D) and a clean side (247C, 447C) by an air cleaner element (237, 437), and the clean side ( 247C, 447C) and a connection pipe (239, 439) through which intake air flows from the clean side (247C, 447C) toward the engine (211, 411), wherein the intake air is connected to the clean side (247C, 447C). A connection pipe upstream guide member (270, 470) is provided to guide the connection pipe inlet (239c, 439c) of the upstream end (239a, 439a) of the pipe (239, 439). (270, 470) is a connecting pipe upstream guide surface (271, 471) having a concave curved surface and a guide opening (270a, 470) which is an opening in the concave curved surface of the connecting pipe upstream guide surface (271, 471). 470a), wherein said guide openings (270a, 470a) are larger than said connecting tube inlets (239c, 439c).

Further, in the above configuration, the connecting pipe upstream guide surface (271) is a concave curved surface that is recessed on the opposite side to the element outlet surface (237b), which is the outlet of intake air in the air cleaner element (237). can be
Further, in the above configuration, at least part of a tangent line (270d) located at the end (270c) on the element exit surface side of the connection pipe upstream guide surface (271) is at least part of the element exit surface (237b). ) may be oriented.

Furthermore, in the above configuration, the guide opening (270a) may open toward the element outlet surface (237b).
Further, in the above configuration, the guide opening (270a) may be arranged along the element outlet surface (237b).

Further, in the above configuration, the distance (L1) between the center (239d) of the connecting pipe inlet (239c) and the element outlet surface (237b) is The distance (L2) between the farthest portion (271a) from the element exit surface (237b) and the element exit surface (237b) may be greater.
Further, in the above configuration, when the upstream end (239a) of the connection pipe (239) is viewed in the axial direction, the connection pipe upstream guide surface (271) The connecting pipe upstream guide surface (271) may surround the connecting pipe (239) from the periphery while having a larger diameter than the inner circumference of the upstream end (239a).

Further, in the above configuration, when viewed in the axial direction of the connection pipe (239), at least part of the connection pipe upstream guide surface (271) may overlap the connection pipe entrance (239c). .
Furthermore, in the above configuration, at least part of the connecting pipe upstream guide surface (271) may overlap the upstream end (239a) from the outer peripheral side in the axial direction of the connecting pipe (239). .

Further, in the above configuration, the connection pipe upstream guide member (270) may be plate-shaped.
Further, in the above configuration, the upstream end (239a) may be arranged inside the concave curved surface of the connection pipe upstream guide surface (271) with respect to the guide opening (270a).

The intake purification device includes an air cleaner box whose interior is partitioned into a dirty side and a clean side by an air cleaner element, and a connecting pipe through which intake air flows from the clean side toward the engine. A connection pipe upstream guide member is provided for guiding intake air to the connection pipe inlet at the upstream end of the connection pipe. a guide opening that is an opening in the concave curved surface of the guide surface, the guide opening being larger than the connecting pipe inlet.
According to this configuration, the intake air on the clean side enters the connecting pipe upstream guide member through the guide opening larger than the connecting pipe inlet of the connecting pipe, and is guided by the concavely curved connecting pipe upstream guide surface for connection. Flow to the pipe connection pipe inlet. Therefore, the connection pipe upstream side guide member facilitates the intake of air into the connection pipe, and the intake efficiency can be improved.

Further, in the above configuration, the connecting pipe upstream guide surface may be a concave curved surface that is recessed on the opposite side to the element exit surface, which is the intake air exit of the air cleaner element.
According to this configuration, the intake air flowing from the element outlet surface of the air cleaner element can be efficiently flowed to the connecting pipe inlet by the connecting pipe upstream side guide surface.
Further, in the above configuration, at least a part of a tangent to the upstream guide surface of the connecting pipe, which is located at the end on the element exit surface side, may be directed to the element exit surface.
According to this configuration, the intake air flowing from the element outlet surface toward the connection pipe can be smoothly taken into the connection pipe upstream side guide member through the guide opening, and the intake efficiency can be improved.

Furthermore, in the configuration described above, the guide opening may open toward the element outlet surface.
According to this configuration, the intake air flowing from the element outlet surface toward the connection pipe can be smoothly taken into the connection pipe upstream side guide member through the guide opening, and the intake efficiency can be improved.
Further, in the above configuration, the guide opening may be arranged in a direction along the element outlet surface.
According to this configuration, the intake air can be efficiently introduced into the connection pipe upstream side guide member from the guide opening.

Further, in the above configuration, the distance between the element outlet surface and the farthest part of the connecting pipe upstream guide surface from the element outlet surface, relative to the distance between the center of the connecting pipe inlet and the element outlet surface. Larger is better.
According to this configuration, the intake air can be guided over a wide range by the connecting pipe upstream side guide surface, and the intake air can efficiently flow to the connecting pipe inlet.
In the above configuration, when viewed in the axial direction of the connecting pipe, the connecting pipe upstream guide surface has a larger diameter than the inner circumference of the upstream end of the connecting pipe, and the connecting pipe upstream guide surface may surround the connecting pipe.
According to this configuration, the connecting pipe upstream guide surface, which has a diameter larger than the inner circumference of the upstream end of the connecting pipe, surrounds the connecting pipe. can flow well.

Further, in the above configuration, when the upstream end of the connecting pipe is viewed in the axial direction, at least a portion of the connecting pipe upstream guide surface may overlap the connecting pipe inlet.
According to this configuration, the intake air can be guided over a wide range by the connecting pipe upstream side guide surface, and the intake air can efficiently flow to the connecting pipe inlet.
Furthermore, in the above configuration, at least part of the connecting pipe upstream guide surface may overlap the upstream end portion of the connecting pipe from the outer peripheral side in the axial direction.
According to this configuration, it is possible to continuously flow the intake air from the connecting pipe upstream guide surface to the upstream end, and to efficiently flow the intake air to the connecting pipe inlet.

Further, in the above configuration, the connection pipe upstream side guide member may be plate-shaped.
With this configuration, the volume occupied by the connecting pipe upstream guide member can be reduced, and the clean side volume can be secured.
Further, in the above configuration, the upstream end portion may be arranged inside the concave curved surface of the connecting pipe upstream guide surface with respect to the guide opening.
According to this configuration, it is possible to continuously flow the intake air from the connecting pipe upstream guide surface to the upstream end, and to efficiently flow the intake air to the connecting pipe inlet.

FIG. 1 is a left side view of a motorcycle. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a cross-sectional view along III-III in FIG. FIG. 4 is a sectional view taken along line IV-IV of FIG. 5 is a cross-sectional view taken along the line VV of FIG. 4. FIG. FIG. 6 is a side view of the connecting pipe upstream guide member viewed from the air cleaner element side. FIG. 7 is a cross-sectional view of the motorcycle in the second embodiment. FIG. 8 is a perspective view of the air intake duct and the periphery of the air intake duct upstream guide member viewed from above with the seat removed. FIG. 9 is a left side view of the motorcycle according to the third embodiment. 10 is a cross-sectional view taken along the line XX of FIG. 9. FIG. FIG. 11 is a left side view of the motorcycle according to the fourth embodiment. 12 is a cross-sectional view taken along line XII-XII of FIG. 11. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description, directions such as front, rear, left, right, and up and down are the same as the directions with respect to the vehicle body unless otherwise specified. In each figure, FR indicates the front of the vehicle body, UP indicates the upper side of the vehicle body, and LH indicates the left side of the vehicle body.

[First embodiment]
A first embodiment to which the present invention is applied will be described below with reference to FIGS. 1 to 6. FIG.

FIG. 1 is a left side view of a motorcycle 201 according to the second embodiment.
A motorcycle 201 has an engine 211 as a power unit supported on a body frame 210 , a front fork 212 supporting a front wheel 202 in a steerable manner, and a swing arm supporting a rear wheel 203 . A vehicle 213 is provided on the rear side of the vehicle body frame 210 .
The motorcycle 201 is a saddle type vehicle in which a rider straddles a seat 214 , and the seat 214 is provided above the rear portion of the body frame 210 .
The motorcycle 201 includes a pair of left and right side covers 215 that cover the vehicle body such as the vehicle body frame 210 .

The body frame 210 includes a head pipe 217 provided at the front end of the body frame 210, one main frame 218 extending rearward and downward from the head pipe 217, and a pivot frame 219 extending downward from the rear end of the main frame 218. .

The engine 211 includes a crankcase 221 supporting a crankshaft 220 extending in the vehicle width direction, and a cylinder portion 222 extending forward of the vehicle from the front surface of the crankcase 221 .
The cylinder portion 222 includes a cylinder 222a that houses a piston (not shown) that reciprocates back and forth, a cylinder head 222b that is connected to the front surface of the cylinder 222a, and a head cover 222c that covers the front surface of the cylinder head 222b.
The engine 211 is a horizontal engine in which the axis 222d of the cylinder 222a extends substantially horizontally in the vehicle front-rear direction when viewed from the side of the vehicle.

The engine 211 is supported by the body frame 210 and arranged in front of the pivot frame 219 and below the main frame 218 . The cylinder portion 222 extends back and forth under the main frame 218 .
An intake device 225 that supplies intake air to the engine 211 is arranged above the cylinder portion 222 .
An exhaust pipe 226 of the engine 211 extends rearward from the lower surface of the cylinder head 222b.

A steering handle 227 is provided at the upper end of the front fork 212 .
The front wheel 202 is supported by the lower ends of the front forks 212 . A front fender 228 is attached to the front fork 212 .

The swing arm 213 is supported by the vehicle body frame 210 via a pivot shaft 213a inserted through its front end. Rear wheel 203 is supported by the rear end of swing arm 213 .
A rear suspension 229 is spanned between the rear portion of the swing arm 213 and the rear portion of the vehicle body.
Fuel tank 223 is provided above main frame 218 and between head pipe 217 and seat 214 .

FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a cross-sectional view along III-III in FIG.
2 and 3, the intake device 225 includes an intake purification device 230, a throttle body 231 that adjusts the flow rate of intake air, and a tubular insulator 232 that connects the throttle body 231 to an intake port on the upper surface of the cylinder head 222b. and

The intake air purifying device 230 includes an air cleaner box 235, a partition wall 236 that partitions the inside of the air cleaner box 235, an air cleaner element 237 that is provided in the partition wall 236, an intake duct 238 that takes intake air into the air cleaner box 235, and an air cleaner box. 235 to the throttle body 231;
Further, the intake air purification device 230 includes an intake duct upstream guide member 240 that guides intake air to the intake duct 238 on the upstream side of the intake duct 238, and an intake duct that guides the intake air to the air cleaner element 237 on the downstream side of the intake duct 238. A downstream guide member 265 and a connection pipe upstream guide member 270 that guides intake air to the connection pipe 239 on the upstream side of the connection pipe 239 are provided.
The intake air purification device 230 is covered from the outside by left and right side covers 215 .

The air cleaner box 235 is arranged below the main frame 218 and above the cylinder portion 222 and positioned between the main frame 218 and the cylinder portion 222 . The air cleaner box 235 is a box-shaped member extending in the vehicle width direction across the main frame 218 located in the center of the vehicle width.

The air cleaner box 235 includes a box-shaped air cleaner case 245 with one of its left and right sides (left side) open outward in the vehicle width direction, and a case cover 246 that closes the opening of the side of the air cleaner case 245 . . Case cover 246 is coupled to peripheral edge portion 245 a of the opening of air cleaner case 245 .

The partition wall 236 is a plate-like member arranged with its plate thickness direction oriented in the vehicle width direction, and partitions the inside of the air cleaner box 235 in the vehicle width direction.
The partition wall 236 partitions the inside of the air cleaner box 235 into a dirty side 247D on the upstream side of the air cleaner element 237 and a clean side 247C on the downstream side of the air cleaner element 237 .
The partition wall 236 is sandwiched between mating surfaces of the air cleaner case 245 and the case cover 246 .

The air cleaner element 237 is a filter that collects dust contained in intake air. The air cleaner element 237 is a plate-like member arranged with its plate thickness direction oriented in the vehicle width direction, and is supported by the partition wall 236 . The air cleaner element 237 has a substantially rectangular shape when viewed from the side of the vehicle.
The air cleaner element 237 and the partition wall 236 are arranged closer to one of the left and right sides (left side) in the air cleaner box 235 so that the clean side 247C has a larger capacity than the dirty side 247D.

The dirty side 247D is a room through which intake air flows before passing through the air cleaner element 237, and is formed between the case cover 246 and the partition wall 236. As shown in FIG.
The clean side 247</b>C is a chamber through which the intake air after being cleaned by passing through the air cleaner element 237 flows, and is formed between the partition wall 236 and the air cleaner case 245 .
The dirty side 247D and the clean side 247C are arranged side by side in the vehicle width direction.

The air cleaner element 237 has an element inlet surface 237a exposed on the dirty side 247D and an element outlet surface 237b opposite to the element inlet surface 237a and exposed on the clean side 247C. The element entrance surface 237a and the element exit surface 237b are flat surfaces and substantially parallel to each other.
Intake air flows into the air cleaner element 237 from the element inlet surface 237a of the dirty side 247D and flows from the element outlet surface 237b to the clean side 247C.

The air intake duct 238 extends rearward outside the air cleaner box 235 from the rear surface of the case cover 246 and communicates the dirty side 247</b>D with the space outside the air cleaner box 235 .
The intake duct 238 is a pipe having a substantially circular cross section and extends in the vehicle front-rear direction within the dirty side 247D. The intake duct 238 is arranged outside the element entrance surface 237a in the vehicle width direction within the dirty side 247D and extends in the vehicle front-rear direction substantially parallel to the element entrance surface 237a along the element entrance surface 237a.

The rear end of the intake duct 238 is an upstream end 238a of the intake duct 238 in the flow of intake air. The intake duct 238 takes in outside air as intake air from a duct inlet 238b on the rear end surface of the upstream end 238a.
The front end of the intake duct 238 is the downstream end 238c of the intake duct 238 in the flow of intake air. A duct outlet 238d on the front end surface of the downstream end portion 238c opens toward the front of the vehicle.
The duct outlet 238d is positioned to overlap the element inlet surface 237a from the outside in the vehicle width direction when viewed from the side of the vehicle.

The connection pipe 239 penetrates the rear surface 245b of the air cleaner case 245 from inside the clean side 247C and extends to the outside of the air cleaner box 235. As shown in FIG. A connection pipe 239 extending outward from the air cleaner box 235 extends downward and inward in the vehicle width direction and is connected to the throttle body 231 below the air cleaner box 235 .

The front end of the connection pipe 239 is an upstream end 239a of the connection pipe 239 in the flow of intake air. The upstream end 239a extends in the vehicle front-rear direction within the clean side 247C. An axis 239b of the connection pipe 239 extends in the vehicle front-rear direction within the clean side 247C.
Intake air in the clean side 247C flows into the connecting pipe 239 from a connecting pipe inlet 239c on the front end face of the upstream end portion 239a. The connection pipe inlet 239c substantially faces the front surface 245c of the air cleaner case 245 from behind.

The upstream end 239a is provided in the clean side 247C on the side opposite to the element exit surface 237b in the vehicle width direction. The air cleaner element 237 is positioned on one of the left and right sides of the main frame 218 , and the connecting pipe 239 is positioned on the other left and right side of the main frame 218 .

The intake duct upstream guide member 240 is arranged upstream of the upstream end 238a of the intake duct 238 in the flow of intake air and behind the upstream end 238a. The intake duct upstream guide member 240 and the intake duct 238 are covered from the outside by the side cover 215 .
The intake duct upstream guide member 240 is a cup-shaped member having a hemispherical cup shape formed by cutting a hollow spherical body in half.
The cup-shaped inner surface of the intake duct upstream guide member 240 is a concave curved duct upstream guide surface 252 . A guide inlet opening 253 that is an opening in the concave curved surface of the duct upstream guide surface 252 exposes the duct upstream guide surface 252 to the outside in the cup shape of the intake duct upstream guide member 240 .

A peripheral edge portion 252a of the duct upstream guide surface 252 that defines the guide entrance opening 253 is substantially circular. The guide entrance opening 253 is generally circular.
The apex 252b of the concave curved surface of the duct upstream guide surface 252 is positioned at the bottom of the cup-shaped inner surface of the intake duct upstream guide member 240. As shown in FIG. The inner diameter of the duct upstream guide surface 252 increases from the vertex 252b toward the guide entrance opening 253 side.

The intake duct upstream guide member 240 is arranged upright so that the guide entrance opening 253 faces the front of the vehicle.
The air intake duct upstream guide member 240 is oriented such that the guide entrance opening 253 faces the duct entrance 238 b of the upstream end 238 a of the air intake duct 238 . The guide inlet opening 253 opens toward the front side of the vehicle.
The inner diameter of the guide entrance opening 253 of the intake duct upstream guide member 240 is larger than the inner diameter of the duct entrance 238b of the intake duct 238 and the outer diameter of the upstream end 238a.

The intake duct 238 has a duct inlet 238b that is entirely positioned inside the concavely curved surface of the duct upstream guide surface 252, and the duct inlet 238b opens inside the duct upstream guide surface 252. As shown in FIG. In other words, the duct inlet 238b is located on the rear side of the guide inlet opening 253 and on the bottom side of the cup shape.
A space is provided in the axial direction of the intake duct 238 between the cup-shaped bottom portion of the duct upstream guide surface 252 and the duct entrance 238b.

Referring to FIG. 3, an axis 238e of intake duct 238 extends in the vehicle front-rear direction. When viewed in the axial direction of the air intake duct 238 , the duct entrance 238 b of the air intake duct 238 overlaps the vertex 252 b of the duct upstream guide surface 252 .

The duct upstream guide surface 252 covers the upstream end 238a of the air intake duct 238 located inside the concave curved surface of the duct upstream guide surface 252 from the periphery and rear side of the upstream end 238a. That is, the guide inlet opening 253 of the duct upstream guide surface 252 overlaps the upstream end 238a from the outer peripheral side in the axial direction of the axis 238e of the upstream end 238a. The upstream end portion 238 a and the duct upstream guide surface 252 are continuous in the intake air flow direction of the intake duct 238 .
Here, the axial direction of the axis 238 e is the flow direction of intake air in the intake duct 238 .

The intake duct downstream guide member 265 is arranged downstream of the downstream end 238c of the intake duct 238 in the dirty side 247D and in front of the downstream end 238c.
The intake duct downstream side guide member 265 has a cup shape obtained by cutting a hollow spherical body at an outlet opening surface 265a into a hemispherical shape, and is further cut at an inlet opening surface 265b substantially orthogonal to the outlet opening surface 265a. is a cup-shaped member.

The intake duct downstream side guide member 265 is arranged with an outlet opening surface 265a, which is a cup-shaped opening surface, directed toward the element inlet surface 237a. When viewed from the side of the vehicle, the exit opening surface 265a overlaps the element entrance surface 237a.
The downstream end 238c of the air intake duct 238 is inserted into the inlet opening surface 265b of the air intake duct downstream guide member 265 from behind, and the duct outlet 238d is at least partially opened within the air intake duct downstream guide member 265. do.

The cup-shaped inner surface of the intake duct downstream guide member 265 is a guide surface 265c that guides intake air toward the element inlet surface 237a. The guide surface 265c is a recessed curved surface in which the cup-shaped inner surface is recessed on the opposite side of the element inlet surface 237a with respect to the outlet opening surface 265a. The guide surface 265c is inclined so as to approach the element inlet surface 237a as the distance from the duct outlet 238d increases in the direction in which the intake air blows out from the duct outlet 238d.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 5 is a cross-sectional view taken along the line VV of FIG. 4. FIG. FIG. 6 is a side view of the connecting pipe upstream guide member 270 viewed from the air cleaner element 237 side.
2 and FIGS. 4 to 6, the connecting pipe upstream guide member 270 is located upstream of the upstream end 239a of the connecting pipe 239 in the clean side 247C and in front of the upstream end 239a. placed.

The connection pipe upstream guide member 270 is shaped like a hemispherical cup shape obtained by cutting a hollow spherical body at a guide opening 270a and further cutting it at an outlet opening 270b substantially orthogonal to the guide opening 270a. is a cup-shaped member. The connection pipe upstream guide member 270 has a shape obtained by bending a flat plate into a cup shape, and the connection pipe upstream guide member 270 is plate-shaped.
The connection pipe upstream side guide member 270 is arranged with the guide opening 270a, which is a cup-shaped opening surface, directed toward the element outlet surface 237b.

The cup-shaped inner surface of the connecting pipe upstream guide member 270 is a connecting pipe upstream guide surface 271 that guides the intake air toward the connecting pipe inlet 239 c of the connecting pipe 239 . The connecting pipe upstream side guide surface 271 is a concave curved surface in which the cup-shaped inner surface is concaved in the opposite direction to the element outlet surface 237b with the guide opening 270a as a reference.
The guide opening 270a exposes the connecting pipe upstream guide surface 271 to the element exit surface 237b side.

The outlet opening 270b is an opening surface formed by cutting out a part of the cup-shaped side surface.
The outlet opening 270b is provided at the rear portion of the connection pipe upstream guide member 270 and opens rearward in the top view of FIG.

The connection pipe upstream guide member 270 is arranged such that the guide opening 270a is separated from the element outlet surface 237b by a predetermined distance in the vehicle width direction. Further, the guide opening 270a is arranged along the element exit surface 237b, and the guide opening 270a and the element exit surface 237b are substantially parallel.
The concave bottom portion 271a of the connecting pipe upstream guide surface 271 when the guide opening 270a is used as a reference is on the side opposite to the element exit surface 237b with respect to the guide opening 270a. The bottom portion 271a is a portion of the connecting pipe upstream guide surface 271 located farthest from the element outlet surface 237b. The inner diameter of the connection pipe upstream guide surface 271 increases from the bottom 271a toward the guide opening 270a.
The bottom portion 271a is located on the cup-shaped bottom surface of the connecting pipe upstream guide member 270, and the guide opening portion 270a faces this bottom surface.

Referring to FIG. 4, a tangent line 270d located at an end portion 270c that defines the guide opening 270a in the tangent line of the connecting pipe upstream guide surface 271 of the connecting pipe upstream guide member 270 is directed to the element outlet surface 237b, It intersects the element exit face 237b. Tangent line 270d intersects element exit face 237b wherever it is located on edge 270c. That is, the tangent line 270d intersects the element outlet surface 237b over the entire circumference of the end portion 270c. At least a portion of the tangent line 270d located at the end portion 270c should be oriented toward the element outlet surface 237b.

When the connection pipe upstream guide member 270 is viewed in a direction perpendicular to the element outlet surface 237b, the guide opening 270a overlaps the element outlet surface 237b. In the second embodiment, the entire guide opening 270a overlaps the element outlet surface 237b, but at least a portion of the guide opening 270a may overlap the element outlet surface 237b.

The rear portion of the connecting pipe upstream guide member 270 is arranged outside the upstream end 239a of the connecting pipe 239 in the vehicle width direction, and covers the upstream end 239a from the side opposite to the element outlet surface 237b.
The upstream end 239a of the connecting pipe 239 enters the connecting pipe upstream guide surface 271 from the outlet opening 270b, and the connecting pipe inlet 239c of the upstream end 239a is inside the connecting pipe upstream guide surface 271. Open forward.
At least a portion of the connecting pipe inlet 239c is arranged inside the connecting pipe upstream guide surface 271 with respect to the guide opening 270a. Also, the connection pipe inlet 239c is located in the upper and lower middle portion of the connection pipe upstream guide surface 271 .

The rear part of the connecting pipe upstream guide surface 271 overlaps the upstream end 239a from the outer peripheral side in the axial direction of the connecting pipe 239, and covers the upstream end 239a from the surroundings.
That is, the connecting pipe upstream guide surface 271 and the upstream end portion 239 a of the connecting pipe 239 are continuous in the axial direction of the connecting pipe 239 .

Further, referring to FIG. 4, the concave bottom portion 271a of the connecting pipe upstream guide surface 271 and the element outlet surface are relative to the distance L1 between the center 239d of the connecting pipe inlet 239c of the connecting pipe 239 and the element outlet surface 237b. 237b is larger. That is, the connecting pipe upstream guide surface 271 is offset from the connecting pipe inlet 239c of the connecting pipe 239 on the side opposite to the element outlet surface 237b.

A front portion 271b of the connection pipe upstream guide surface 271 is curved toward the element exit surface 237b side toward the front side when viewed from above in FIG.
When the connecting pipe inlet 239c is viewed in the axial direction of the connecting pipe 239, the front portion 271b of the connecting pipe upstream guide surface 271 overlaps the connecting pipe inlet 239c from the front, and at least a portion of the connecting pipe inlet 239c is positioned upstream. cover from

When viewed in the axial direction of the connecting pipe 239, the inner diameter of the connecting pipe upstream guide surface 271 is larger than the diameter of the inner circumference of the connecting pipe inlet 239c of the connecting pipe 239, that is, the inner diameter of the connecting pipe inlet 239c.
The upstream end portion 239a is surrounded from above, from outside in the vehicle width direction, and from below by a connection pipe upstream guide surface 271 having a diameter larger than that of the upstream end portion 239a.
Further, the connecting pipe upstream guide member 270 is a part manufactured in a separate process from that of the connecting pipe 239 . Therefore, the connection pipe 239 can be formed in a simple shape, and the connection pipe upstream guide member 270 can be easily formed to have a larger diameter than the connection pipe 239 .

The connection pipe upstream guide member 270 includes a fixing hole 272 penetrating the connection pipe upstream guide surface 271 in the vehicle width direction. The fixing hole portion 272 is provided near the bottom portion 271a.
Of the side walls of the air cleaner case 245, a side wall 245d located outside in the vehicle width direction with respect to the connecting pipe 239 has an engaging portion 273 protruding into the clean side 247C.
The connecting pipe upstream guide member 270 is fixed to the air cleaner case 245 by engaging the engaging portion 273 with the fixing hole portion 272 .
The connection pipe upstream guide member 270 also has a flange portion 274 extending downward from the outer periphery of the connection pipe upstream guide surface 271 and engages the air cleaner case 245 via the flange portion 274 .

Here, the flow of intake air in intake device 225 will be described.
2 and 3, outside air flows as intake air W from the guide entrance opening 253 on the front surface of the intake duct upstream guide member 240 into the concave curved surface of the duct upstream guide surface 252 . Intake air W flows from the guide entrance opening 253 side along the duct upstream guide surface 252 toward the vertex 252b side, and then turns forward in the vicinity of the vertex 252b to reach the duct entrance of the upstream end portion 238a of the intake duct 238. 238b.
Here, since the guide inlet opening 253 of the intake duct upstream guide member 240 opens forward of the vehicle, the running wind when the motorcycle 201 travels forward flows directly into the guide inlet opening 253 . For this reason, the running wind can be efficiently taken in from the guide entrance opening 253 to the duct upstream side guide surface 252 as the intake air W.
In addition, since the inner diameter of the guide entrance opening 253 of the intake duct upstream guide member 240 is larger than the inner diameter of the duct entrance 238b of the intake duct 238, the intake air W is collected by the intake duct upstream guide member 240, and the gathered intake air W can be supplied to the duct entrance 238b, and the intake air W can be efficiently flown through the intake duct 238.

The duct entrance 238b of the air intake duct 238 is positioned inside the concave surface of the duct upstream guide surface 252, and the duct entrance 238b and the duct upstream guide surface 252 are continuous in the axial direction of the air intake duct 238. . Therefore, the intake air W guided by the duct upstream guide surface 252 can efficiently flow to the duct inlet 238b.
Furthermore, when viewed in the axial direction of the air intake duct 238, the duct entrance 238b of the air intake duct 238 overlaps with the vertex 252b of the duct upstream guide surface 252, so that the intake air W that is turned forward from the vicinity of the vertex 252b can be efficiently passed through the duct entrance. 238b.

The intake air W that has flowed into the air intake duct 238 from the duct inlet 238b flows from the duct outlet 238d at the front end of the air intake duct 238 into the dirty side 247D.
Specifically, the intake air W flowing into the dirty side 247D from the duct outlet 238d flows along the curved surface of the guide surface 265c of the intake duct downstream side guide member 265 and changes its direction toward the element inlet surface 237a on the inner side in the vehicle width direction. , from the outlet opening face 265a toward the element inlet face 237a. Therefore, intake air W can be efficiently supplied from the intake duct 238 to the air cleaner element 237 .

2 to 5, the intake air W that has flowed into the air cleaner element 237 from the element inlet surface 237a flows into the clean side 247C from the element outlet surface 237b, is guided by the connecting pipe upstream guide member 270, and flows into the connecting pipe. 239.
Specifically, the intake air W on the clean side 247C flows into the connection pipe upstream guide surface 271 from the guide opening 270a, flows backward along the curved surface of the connection pipe upstream guide surface 271, and reaches the upstream end. It flows into the connecting pipe 239 from the connecting pipe inlet 239c of 239a.
Intake air W of the connecting pipe 239 flows through the throttle body 231 and the insulator 232 to the intake port on the upper surface of the cylinder head 222b.
Here, since the inner diameter of the guide opening 270a of the connecting pipe upstream guide member 270 is larger than the inner diameter of the connecting pipe inlet 239c of the connecting pipe 239, the intake air W is collected by the connecting pipe upstream guide surface 271, and this collected The intake air W can be supplied to the connection pipe inlet 239c, and the intake air W can efficiently flow through the connection pipe 239.

A connecting pipe inlet 239c of the connecting pipe 239 is positioned inside the concavely curved surface of the connecting pipe upstream guide surface 271, and the connecting pipe upstream guide surface 271 and the connecting pipe inlet 239c are arranged in the axial direction of the connecting pipe 239. Contiguous. Therefore, the intake air W guided by the connecting pipe upstream guide surface 271 can efficiently flow to the connecting pipe inlet 239c.

As described above, according to the first embodiment to which the present invention is applied, the intake air purification device 230 includes the air cleaner box 235 whose inside is divided into the dirty side 247D and the clean side 247C by the air cleaner element 237. and a connection pipe 239 through which intake air flows from the clean side 247C toward the engine 211 side. A pipe upstream guide member 270 is provided, and the connection pipe upstream guide member 270 includes a concave curved connection pipe upstream guide surface 271 and a guide opening that is an opening in the concave curved surface of the connection pipe upstream guide surface 271 . 270a, the guide opening 270a being larger than the connecting tube inlet 239c.
According to this configuration, the intake air from the clean side 247C enters the connecting pipe upstream guide member 270 through the guide opening 270a, which is larger than the connecting pipe inlet 239c of the connecting pipe 239. 271 and flows into the connecting pipe inlet 239c of the connecting pipe 239. As shown in FIG. Therefore, the connection pipe upstream side guide member 270 facilitates the intake of air into the connection pipe 239, thereby improving the intake efficiency.

The connection pipe upstream guide surface 271 is a concave curved surface that is recessed in the opposite direction to the element outlet surface 237b that is the intake air outlet surface of the air cleaner element 237. The bottom portion 271a is positioned opposite the element outlet surface 237b with respect to the guide opening 270a.
According to this configuration, the intake air flowing from the element outlet surface 237b of the air cleaner element 237 can be efficiently flowed to the connecting pipe inlet 239c by the connecting pipe upstream guide surface 271. As shown in FIG.
In addition, at least a portion of a tangent line 270d located at an end portion 270c on the element outlet surface 237b side of the connecting pipe upstream guide surface 271 is oriented toward the element outlet surface 237b.
According to this configuration, the intake air flowing from the element outlet surface 237b toward the connecting pipe 239 can be smoothly taken into the connecting pipe upstream side guide member 270 through the guide opening 270a, and the intake efficiency can be improved.

Further, the guide opening 270a opens toward the element exit surface 237b.
According to this configuration, the intake air flowing from the element outlet surface 237b toward the connecting pipe 239 can be smoothly taken into the connecting pipe upstream side guide member 270 through the guide opening 270a, and the intake efficiency can be improved.
Also, the guide opening 270a is oriented along the element outlet surface 237b.
According to this configuration, the intake air can be efficiently taken into the connection pipe upstream guide member 270 from the guide opening 270a.

Further, with respect to the distance L1 between the center 239d of the connecting pipe inlet 239c and the element outlet surface 237b, the bottom portion 271a, which is the farthest portion of the connecting pipe upstream guide surface 271 from the element outlet surface 237b, and the element outlet surface 237b The distance L2 between is greater.
According to this configuration, the intake air can be guided over a wide range by the connection pipe upstream guide surface 271, and the intake air can efficiently flow to the connection pipe inlet 239c.
Further, when the upstream end portion 239a of the connecting pipe 239 is viewed in the axial direction, the connecting pipe upstream guide surface 271 has a larger diameter than the inner circumference of the upstream end portion 239a of the connecting pipe 239, The pipe upstream guide surface 271 surrounds the connection pipe 239 from the periphery.
According to this configuration, since the connection pipe upstream guide surface 271 having a diameter larger than the inner circumference of the upstream end portion 239a of the connection pipe 239 surrounds the connection pipe 239, the connection pipe upstream guide surface 271 guides the intake air. It can efficiently flow to the connecting pipe inlet 239c.

Further, when viewed in the axial direction of the connecting pipe 239, at least a portion of the connecting pipe upstream guide surface 271 overlaps the connecting pipe inlet 239c.
According to this configuration, the intake air can be guided over a wide range by the connection pipe upstream guide surface 271, and the intake air can efficiently flow to the connection pipe inlet 239c.
Furthermore, at least a portion of the connecting pipe upstream guide surface 271 overlaps the upstream end portion 239a of the connecting pipe 239 in the axial direction from the outer peripheral side.
According to this configuration, it is possible to continuously flow the intake air from the connection pipe upstream guide surface 271 to the upstream end portion 239a, and to efficiently flow the intake air to the connection pipe inlet 239c.

Further, the connection pipe upstream side guide member 270 is plate-shaped.
With this configuration, the volume occupied by the connecting pipe upstream guide member 270 can be reduced, and the volume of the clean side 247C can be secured.
Further, the upstream end portion 239a is arranged inside the concave curved surface of the connection pipe upstream guide surface 271 with respect to the guide opening portion 270a.
According to this configuration, it is possible to continuously flow the intake air from the connection pipe upstream guide surface 271 to the upstream end portion 239a, and to efficiently flow the intake air to the connection pipe inlet 239c.

Further, according to the first embodiment to which the present invention is applied, the intake air purification device 230 includes an air cleaner box 235 whose interior is partitioned into a dirty side 247D and a clean side 247C by an air cleaner element 237, and a dirty side 247C. 247D is provided with an intake duct 238 for introducing outside air as intake air, and an intake duct 238 for guiding the intake air to a duct entrance 238b at an upstream end 238a of the intake duct 238 on the upstream side of the intake duct 238 outside the air cleaner box 235. A duct upstream guide member 240 is provided, and the intake duct upstream guide member 240 has a concave curved duct upstream guide surface 252 and a guide inlet opening 253 which is an opening in the concave curved surface of the duct upstream guide surface 252 . and the guide inlet opening 253 is larger than the duct inlet 238b.
According to this configuration, the intake air enters the intake duct upstream guide member 240 through the guide entrance opening 253 larger than the duct entrance 238b of the intake duct 238, and is guided by the concave curved duct upstream guide surface 252. It flows to the duct inlet 238b of the intake duct 238. Therefore, the air intake duct upstream guide member 240 facilitates the intake of air into the air intake duct 238, thereby improving the air intake efficiency.

Also, the guide entrance opening 253 opens in a direction facing the duct entrance 238b.
According to this configuration, since the guide entrance opening 253 opens in a direction facing the duct entrance 238b, the intake air flowing from the guide entrance opening 253 to the concavely curved duct upstream guide surface 252 is efficiently directed toward the duct entrance 238b. can flow to
The intake air purification device 230 is mounted on the motorcycle 201, and the guide entrance opening 253 opens toward the front of the vehicle.
According to this configuration, the running wind of the motorcycle 201 running forward can be efficiently taken into the duct upstream side guide surface 252 from the guide entrance opening 253 that opens toward the front of the vehicle. can flow efficiently.

Further, the guide inlet opening 253 overlaps the upstream end 238a of the intake duct 238 in the axial direction of the axis 238e of the upstream end 238a of the intake duct 238 .
According to this configuration, since the guide entrance opening 253 overlaps the upstream end 238a of the intake duct 238, the flow of intake air around the upstream end 238a can be stabilized, and the intake efficiency can be improved.

[Second embodiment]
A second embodiment to which the present invention is applied will be described below with reference to FIGS. 7 and 8. FIG.
The second embodiment describes a motorcycle 401 that is different from the motorcycle 201 of the first embodiment.

FIG. 7 is a cross-sectional view of a motorcycle 401 according to the second embodiment.
A motorcycle 401 has an engine 411 supported by a vehicle body frame 410 , and a front fork (not shown) that steerably supports a front wheel (not shown) is steerably supported at the front end of the vehicle body frame 410 to support a rear wheel 403 . This vehicle has a swing arm (not shown) provided on the rear side of the vehicle body frame 410 .
The motorcycle 401 is a saddle-ride type vehicle in which a rider sits astride a seat 414 .

The vehicle body frame 410 includes a pair of left and right seat frames 418 behind the engine 411 that extend in the front-rear direction and support the seat 414 from below.
A fuel tank 423 is provided above the engine 411 and in front of the seat 414 .

The engine 411 includes a crankcase 421 and a cylinder portion 422 extending upward from the upper surface of the front portion of the crankcase 421 .
An intake device 425 that supplies intake air to the cylinder portion 422 is arranged behind the cylinder portion 422 and below the seat 414 .
The motorcycle 401 includes a rear fender 444 that covers the space between the left and right seat frames 418 from below.

The intake device 425 includes an intake purification device 430 and a throttle body 431 connected to an intake port on the rear surface of the cylinder portion 422 .

The intake air purification device 430 includes an air cleaner box 435, a partition wall 436 that partitions the inside of the air cleaner box 435, an air cleaner element 437 that is provided in the partition wall 436, an intake duct 438 that takes in the air into the air cleaner box 435, and an air cleaner box. 435 and a connecting pipe 439 that connects the throttle body 431 .
Further, the intake air purification device 430 includes an intake duct upstream guide member 440 that guides the intake air to the intake duct 438 on the upstream side of the intake duct 438, and an intake duct that guides the intake air to the air cleaner element 437 on the downstream side of the intake duct 438. A downstream guide member 465 and a connection pipe upstream guide member 470 that guides intake air to the connection pipe 439 on the upstream side of the connection pipe 439 are provided.

The air cleaner box 435 is a box-shaped member arranged between the left and right seat frames 418 . The air cleaner box 435 is positioned above the front of the rear wheel 403 and below the seat 414 and is covered with the seat 414 from above.

The partition wall 436 partitions the inside of the air cleaner box 435 into a dirty side 447D on the upstream side of the air cleaner element 437 and a clean side 447C on the downstream side of the air cleaner element 437. As shown in FIG. The partition wall 436 is a plate-like member arranged with its plate thickness direction oriented in the vertical direction, and partitions the inside of the air cleaner box 435 in the vertical direction.

The air cleaner element 437 is a plate-like member arranged with the plate thickness direction oriented in the vertical direction, and is supported by the partition wall 436 . The air cleaner element 437 is disposed so as to be inclined forward and downward when viewed from the side of the vehicle.

The dirty side 447D is a chamber through which intake air flows before passing through the air cleaner element 437, and is provided in the lower part inside the air cleaner box 435. As shown in FIG.
The clean side 447</b>C is a chamber through which the intake air after being purified by passing through the air cleaner element 437 flows, and is provided in the upper part of the air cleaner box 435 .
The air cleaner element 437 has an element inlet surface 437a exposed on the dirty side 447D and an element outlet surface 437b exposed on the clean side 447C.

The air intake duct 438 extends from the rear of the air cleaner box 435 to the outside of the air cleaner box 435 and communicates the dirty side 447</b>D with the space outside the air cleaner box 435 .
Air intake duct 438 extends rearward through a space between seat 414 and rear fender 444 . Also, the intake duct 438 is positioned between the left and right seat frames 418 .

The rear end of the intake duct 438 is an upstream end 438a of the intake duct 438 in the flow of intake air. The intake duct 438 takes in outside air as intake from a duct inlet 438b on the rear end surface of the upstream end 438a.
The front end of the intake duct 438 is the downstream end 438c of the intake duct 438 in the flow of intake air. The downstream end 438c extends back and forth below the element inlet surface 437a and substantially parallel to the element inlet surface 437a. Intake air flows into the dirty side 447D from the duct outlet 438d on the front end surface of the downstream end 438c.
A cup-shaped intake duct downstream guide member 465 that opens toward the element inlet surface 437a is attached to the downstream end 438c of the intake duct 438. As shown in FIG. The intake duct downstream side guide member 465 guides the intake air flowing into the dirty side 447D from the duct outlet 438d to the element inlet surface 437a.

The connection pipe 439 penetrates the front surface of the air cleaner box 435 from within the clean side 447</b>C, extends forward outside the air cleaner box 435 , and is connected to the throttle body 431 .
An upstream end 439a of the connecting pipe 439 in the flow of intake air is positioned above the element outlet surface 437b within the clean side 447C and extends back and forth substantially parallel to the element outlet surface 437b. Intake air in the clean side 447C flows into the connecting pipe 439 from the connecting pipe inlet 439c on the rear end surface of the upstream end portion 439a.

A connection pipe upstream guide member 470 is attached to the upstream end portion 439 a of the connection pipe 439 . The connecting pipe upstream guide member 470 guides the intake air flowing into the clean side 447C from the element outlet surface 437b to the connecting pipe inlet 439c.
The connection pipe upstream guide member 470 is shaped such that a hollow spherical body is cut at a guide opening 470a to form a hemispherical cup shape, which is further cut at an outlet opening 470b substantially orthogonal to the guide opening 470a. is a cup-shaped member.
The connection pipe upstream guide member 470 is arranged with the guide opening 470a, which is a cup-shaped opening surface, directed toward the element outlet surface 437b.
The cup-shaped inner surface of the connecting pipe upstream guide member 470 is a curved connecting pipe upstream guide surface 471 that guides the intake air toward the connecting pipe inlet 439c.
The upstream end 439a of the connecting tube 439 enters the connecting tube upstream guide surface 471 through the outlet opening 470b.
The inner diameter of the guide opening 470 a of the connecting pipe upstream guide member 470 is larger than the inner diameter of the connecting pipe inlet 439 c of the connecting pipe 439 .

FIG. 8 is a perspective view of the intake duct 438 and the periphery of the intake duct upstream guide member 440 viewed from above with the sheet 414 removed.
7 and 8, intake duct upstream guide member 440 is arranged upstream of upstream end 438a of intake duct 438 in the flow of intake air and behind upstream end 438a. The intake duct upstream guide member 440 is attached to the outer periphery of the upstream end 438a.

The intake duct upstream guide member 440 includes a guide portion 450 that guides intake air toward the duct inlet 438b of the upstream end portion 438a of the intake duct 438, and a duct mounting portion 451 attached to the intake duct 438. As shown in FIG.

The guide part 450 is a cup-shaped member having a hemispherical cup shape formed by cutting a hollow spherical body in half.
The cup-shaped inner surface of the guide portion 450 is a concave curved duct upstream guide surface 452 . A guide entrance opening 453 that is an opening in the concave curved surface of the duct upstream guide surface 452 exposes the duct upstream guide surface 452 to the outside in the cup shape of the guide portion 450 .

A peripheral edge portion 452a of the duct upstream guide surface 452 that defines the guide entrance opening 453 is arcuate.
The apex 452 b of the concavely curved surface of the duct upstream guide surface 452 is positioned at the bottom of the inner surface of the cup-shaped guide portion 450 . The inner diameter of the duct upstream guide surface 452 increases from the vertex 452b toward the guide entrance opening 453 side.
In addition, the guide portion 450 includes a cutout opening 475 formed by cutting out a portion around the guide inlet opening 453 in the guide portion 450 .

The intake duct upstream guide member 440 is arranged upright so that the guide entrance opening 453 of the guide portion 450 faces the front of the vehicle.
The cutout opening 475 includes an upper surface opening 475a formed by cutting the upper surface of the guide portion 450 and a pair of side openings 475b formed by cutting left and right side surfaces of the guide portion 450 .

The intake duct upstream guide member 440 is arranged such that the guide entrance opening 453 of the guide portion 450 faces the duct entrance 438b of the upstream end 438a of the intake duct 438 . The guide inlet opening 453 opens toward the front side of the vehicle.
The inner diameter of the guide inlet opening 453 of the guide portion 450 is larger than the inner diameter of the duct inlet 438b of the intake duct 438 and the outer diameter of the upstream end 438a.

A band member 476 is attached to the outer circumference of the upstream end 438 a of the intake duct 438 . The band member 476 is provided so as to wrap around the outer periphery of the upstream end portion 438a.
The duct attachment portion 451 of the intake duct upstream guide member 440 extends forward with respect to the guide inlet opening 453 and is fixed to the band member 476 . That is, the intake duct upstream guide member 440 is supported by the intake duct 438 via the band member 476 .

7 and 8, outside air flows as intake air W from the guide entrance opening 453 and the notch opening 475 of the intake duct upstream guide member 440 into the concave curved surface of the duct upstream guide surface 452. do. The intake air W flows along the duct upstream guide surface 452 toward the vertex 452b, then turns forward in the vicinity of the vertex 452b and flows into the duct entrance 438b of the upstream end 438a of the intake duct 438.

As described above, according to the second embodiment to which the present invention is applied, the intake duct upstream guide member 440 is fixed to the intake duct 438 .
According to this configuration, the assembly error of the intake duct upstream guide member 440 with respect to the intake duct 438 can be reduced, and the intake duct upstream guide member 440 can be fixed at the correct position.

[Third embodiment]
A third embodiment to which the present invention is applied will be described below with reference to FIGS. 9 to 10. FIG.
The third embodiment describes a motorcycle 501 that is different from the motorcycle 201 of the first embodiment.

FIG. 9 is a left side view of motorcycle 501 in the third embodiment. 10 is a cross-sectional view taken along the line XX of FIG. 9. FIG.
A motorcycle 501 is a straddle-type vehicle having an engine 511 between a front wheel 502 and a rear wheel 503 .
The motorcycle 501 has an air intake device 525 behind the engine 511 and below the passenger seat 514 .
Intake device 525 includes an intake purification device 530 and a throttle body 531 connected to an intake port of engine 511 .

The intake air purification device 530 includes an air cleaner box 535, a partition wall 536 that partitions the inside of the air cleaner box 535, an air cleaner element 537 that is provided in the partition wall 536, an intake duct 538 that takes in the air into the air cleaner box 535, and an air cleaner box. 535 and a connecting pipe 539 that connects the throttle body 531 .

Further, the intake air purification device 530 includes an intake duct upstream guide member 540 that guides the intake air to the intake duct 538 on the upstream side of the intake duct 538, and an intake duct that guides the intake air to the air cleaner element 537 on the downstream side of the intake duct 538. A downstream guide member 565 and a connection pipe upstream guide member 570 that guides intake air to the connection pipe 539 on the upstream side of the connection pipe 539 are provided.
The intake duct upstream guide member 540 has the same structure and function as the intake duct upstream guide member 240 of the second embodiment, and detailed description thereof will be omitted.
The intake duct downstream guide member 565 has the same structure and function as the intake duct downstream guide member 265 of the second embodiment, and detailed description thereof will be omitted.
The connection pipe upstream guide member 570 has the same structure and function as the connection pipe upstream guide member 270 of the second embodiment, and detailed description thereof will be omitted.

The partition wall 536 and the air cleaner element 537 partition the interior of the air cleaner box 535 in the vehicle width direction, and a dirty side 547D is defined on one side of the partition wall 536 in the vehicle width direction, and a dirty side 547D is defined on the other side of the partition wall 536 in the vehicle width direction. A clean side 547C is defined.
The partition wall 536 and the air cleaner element 537 are plate-like members arranged with the plate thickness direction directed in the vehicle width direction.

The air intake duct 538 extends rearward from the rear portion of the air cleaner box 535 and communicates the dirty side 547D with the space outside the air cleaner box 535 .
The rear end of the intake duct 538 is an upstream end 538a of the intake duct 538 in the flow of intake air. An intake duct upstream guide member 540 is attached to the upstream end 538a.
The front end of the intake duct 538 is the downstream end 538c of the intake duct 538 in the flow of intake air. An intake duct downstream guide member 565 is attached to the downstream end 538c.

The connection pipe 539 extends forward through the front surface of the air cleaner box 535 from within the clean side 547</b>C and is connected to the throttle body 531 .
A rear end portion of the connection pipe 539 is an upstream end portion 539a of the connection pipe 539 in the flow of intake air. A connection pipe upstream guide member 570 is attached to the upstream end 539a.

[Fourth embodiment]
A fourth embodiment to which the present invention is applied will be described below with reference to FIGS. 11 and 12. FIG.
The fourth embodiment describes a motorcycle 601 that is different from the motorcycle 201 of the first embodiment.

FIG. 11 is a left side view of motorcycle 601 in the fourth embodiment. 12 is a cross-sectional view taken along line XII-XII of FIG. 11. FIG.
The motorcycle 601 is a saddle-ride type vehicle having a passenger seat 614 between front wheels 602 and rear wheels 603 .
The motorcycle 601 is a scooter-type saddle-ride type vehicle provided with a unit swing engine 611 integrally including a swing arm portion 611a for swingably supporting a rear wheel 603 on the vehicle body and an engine 611b.

The intake device 625 is attached to the upper surface of the swing arm portion 611 a and swings up and down integrally with the unit swing engine 611 .
The intake device 625 includes an intake purification device 630 and a throttle body (not shown) connected to an intake port of the engine 611b.

The intake air purification device 630 includes an air cleaner box 635, a partition wall 636 that partitions the inside of the air cleaner box 635, an air cleaner element 637 that is provided in the partition wall 636, an intake duct 638 that introduces the intake air into the air cleaner box 635, and an air cleaner box. and a connecting pipe 639 that connects 635 to the throttle body.

Further, the intake air purification device 630 includes an intake duct upstream guide member 640 that guides intake air to the intake duct 638 on the upstream side of the intake duct 638, and an intake duct that guides the intake air to the air cleaner element 637 on the downstream side of the intake duct 638. A downstream guide member 665 and a connection pipe upstream guide member 670 that guides intake air to the connection pipe 639 on the upstream side of the connection pipe 639 are provided.
The intake duct upstream guide member 640 has the same structure and function as the intake duct upstream guide member 240 of the second embodiment, and detailed description thereof will be omitted.
The intake duct downstream guide member 665 has the same structure and function as the intake duct downstream guide member 265 of the second embodiment, and detailed description thereof will be omitted.
The connection pipe upstream guide member 670 has the same structure and function as the connection pipe upstream guide member 270 of the second embodiment, and detailed description thereof will be omitted.

The air cleaner box 635 is arranged outside the rear wheel 603 . A side cover 635 a is attached to the outer surface of the air cleaner box 635 .
The partition wall 636 and the air cleaner element 637 partition the inside of the air cleaner box 635 in the vehicle width direction, and the dirty side 647D is defined outside the partition wall 636 in the vehicle width direction, and the clean side is partitioned inside the partition wall 636 in the vehicle width direction. 647C is partitioned.
The partition wall 636 and the air cleaner element 637 are plate-like members arranged with the plate thickness direction oriented in the vehicle width direction.

The air intake duct 638 extends forward from the front portion of the air cleaner box 635 and communicates the dirty side 647D with the space outside the air cleaner box 635 .
The front end of the intake duct 638 is the upstream end 638a of the intake duct 638 in the flow of intake air. An intake duct upstream guide member 640 is attached to the upstream end 638a. The intake duct upstream guide member 640 is covered from the side by a side cover 635a.
The rear end of the intake duct 638 is the downstream end 638c of the intake duct 638 in the flow of intake air. An intake duct downstream guide member 665 is attached to the downstream end 638c.

The connection pipe 639 extends forward from inside the clean side 647C through the front surface of the air cleaner box 635 and is connected to the throttle body.
A rear end portion of the connection pipe 639 is an upstream end portion 639a of the connection pipe 639 in the flow of intake air. A connection pipe upstream guide member 670 is attached to the upstream end 639a.

211, 411 engine 230, 430 intake purification device 235, 435 air cleaner box 239, 439 connecting pipe 239a, 439a upstream end (upstream end of connecting pipe)
239c, 439c Connecting pipe inlet 239d Center 237, 437 Air cleaner element 237b, 437b Element outlet surface 247C, 447C Clean side 247D, 447D Dirty side 270, 470 Connecting pipe upstream guide member 270a, 470a Guide opening 270c End 270d Tangent line 271, 471 Connecting pipe upstream guide surface 271a Bottom (farthest part)
L1 distance (distance between the center of the inlet aperture and said outlet face)
L2 distance (distance between the element outlet surface and the farthest part from the element outlet surface of the connecting pipe upstream guide surface)

Claims (11)

From an air cleaner box (235, 435) whose interior is partitioned into a dirty side (247D, 447D) and a clean side (247C, 447C) by an air cleaner element (237, 437), and the clean side (247C, 447C) and a connection pipe (239, 439) through which intake air flows toward the engine (211, 411),
In the clean side (247C, 447C), a connection pipe upstream guide member for guiding intake air to the connection pipe inlet (239c, 439c) of the upstream end (239a, 439a) of the connection pipe (239, 439) (270, 470) is provided,
The connecting pipe upstream guide member (270, 470) comprises a connecting pipe upstream guide surface (271, 471) having a concave curved surface and an opening in the concave curved surface of the connecting pipe upstream guide surface (271, 471). a guide opening (270a, 470a);
The guide openings (270a, 470a) are larger than the connecting pipe inlets (239c, 439c),
The upstream end (239a, 439a) is arranged inside the concave surface of the connection pipe upstream guide surface (271, 471) with respect to the guide opening (270a, 470a). Intake air purification device. The connection pipe upstream guide surface (271) is a concave curved surface that is recessed on the opposite side to an element outlet surface (237b), which is an outlet of intake air in the air cleaner element (237). 1. The intake air purification device according to 1. At least part of a tangent line (270d) located at the end (270c) on the element outlet surface (237b) side of the connecting pipe upstream guide surface (271) is oriented toward the element outlet surface (237b). 3. The intake air purification system according to claim 2, characterized in that: The intake air purification device according to claim 2 or 3, wherein the guide opening (270a) opens toward the element outlet surface (237b). The intake air purification device according to any one of claims 2 to 4, wherein the guide opening (270a) is arranged along the element outlet surface (237b). With respect to the distance (L1) between the center (239d) of the connecting pipe inlet (239c) and the element outlet surface (237b), the element outlet surface (237b) of the connecting pipe upstream guide surface (271) 6. An intake air purifier according to any one of claims 2 to 5, wherein the distance (L2) between the portion (271a) farthest from the element outlet surface (237b) is greater. When the upstream end (239a) of the connecting pipe (239) is viewed in the axial direction, the connecting pipe upstream guide surface (271) is aligned with the upstream end (239a) of the connecting pipe (239). ), and the connecting pipe upstream guide surface (271) surrounds the connecting pipe (239). Intake purification device. 8. At least part of the connecting pipe upstream guide surface (271) overlaps the connecting pipe inlet (239c) when viewed in the axial direction of the connecting pipe (239). The intake air purification device according to any one of 1. 8. At least part of the connecting pipe upstream guide surface (271) overlaps the upstream end (239a) from the outer peripheral side in the axial direction of the connecting pipe (239). The intake air purification device according to any one of 1. The intake air purification device according to any one of claims 1 to 9, wherein the connecting pipe upstream guide member (270) is plate-shaped. From an air cleaner box (235, 435) whose interior is partitioned into a dirty side (247D, 447D) and a clean side (247C, 447C) by an air cleaner element (237, 437), and the clean side (247C, 447C) and a connection pipe (239, 439) through which intake air flows toward the engine (211, 411),
In the clean side (247C, 447C), a connection pipe upstream guide member for guiding intake air to the connection pipe inlet (239c, 439c) of the upstream end (239a, 439a) of the connection pipe (239, 439) (270, 470) is provided,
The connecting pipe upstream guide member (270, 470) comprises a connecting pipe upstream guide surface (271, 471) having a concave curved surface and an opening in the concave curved surface of the connecting pipe upstream guide surface (271, 471). a guide opening (270a, 470a);
The guide openings (270a, 470a) are larger than the connecting pipe inlets (239c, 439c),
When the upstream end (239a, 439a) of the connection pipe (239, 439) is viewed in the axial direction, the connection pipe upstream guide surface (271, 471) has a larger diameter than the inner circumference of the upstream end (239a, 439a) of the connecting pipe, and the connecting pipe upstream guide surface (271, 471) surrounds the connecting pipe (239, 439). An intake purification device characterized by:

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