JP2639608B2 - Motorcycle air intake system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for removing secondary air from an air cleaner for purifying exhaust gas and a structure for introducing a breather tube into the air cleaner.

[0002]

2. Description of the Related Art In a secondary air supply system for newly supplying insufficient oxygen in order to purify exhaust gas by oxidizing HC and CO in an exhaust gas of an engine in an exhaust system, secondary air is supplied from an air cleaner to an exhaust gas of the engine. Powered to port.

Conventionally, a secondary air take-out tube for taking out the secondary air from the air cleaner is provided between the air cleaner and the engine.
Provided connecting tube that connects the intake side
There is an example (Japanese Utility Model Publication No. 60-194160)
The intake system including the secondary air extraction tube
There is no disclosure as to how it can be assembled.

[0004]

[Problem to be Solved] In the case of a motorcycle, the size of the body is large.
When it comes to avoiding mold, space is extremely limited,
Motorcycles with an air cleaner behind the engine
Compact intake system due to the relationship with the rear cushion
It is not easy to assemble to the car body. The present invention has been made in view of such a point, and the object thereof is to provide a vehicle body.
Can be mounted compactly,
Another object of the present invention is to provide a motorcycle intake device that can be reduced in size .

[0005] To achieve the above object, the present invention is, before
Place the engine between the wheel and the rear wheel, and behind the engine
A rear cushion that is almost vertically oriented close to
And an air cleaner behind the rear cushion
In a motorcycle having a configuration and a secondary air introduction device for purifying exhaust gas, a motorcycle is provided with an opening at a front wall opening of the air cleaner.
Connect the connecting tube and connect the connecting tube.
The tube body extends forward on one side of the rear cushion
And connect the front end to the carburetor and connect
The sub-chamber integrated with the tube is
The other side of the vehicle swells forward and a secondary air take-out tube is connected to the sub-chamber to provide an intake device for a motorcycle.

A connector connected to an opening of a front wall of an air cleaner.
Body of the toning tube is on one side of the rear cushion
To the carburetor and connect the connecting tube.
The sub-chamber formed integrally with the
Bulge the other side forward and connect to the secondary air extraction tube.
As it continues, empty space around the rear cushion
Utilizing connecting tube body and sub-chamber
Is installed, and the intake device is compactly assembled to the vehicle body.
Air cleaner, and remove the air cleaner
And the overall length of the vehicle can be kept small.
Can be. In addition, since the secondary air extraction tube is connected to the sub-chamber formed integrally with the connecting tube, the assembling property is good. Similarly, by connecting the breather tube for reducing the blow-by gas to the sub-chamber, the assembling property is further improved.

[0007]

[Embodiment] An embodiment of the present invention shown in FIGS. 1 to 8 will be described below.

FIG. 1 is an overall side view of a motorcycle 1 according to the present embodiment. 1 from the upper rear side of the head pipe 2 to the rear
The main pipe 3 extends slightly downward, and the down pipe 4 extends obliquely downward from the lower rear surface of the head pipe 2 so that the main pipe 3 and the down pipe 4 extend downward.
A reinforcement stay 5 is erected between them.

A pair of left and right center pipes 6 extend obliquely downward from the rear end of the main pipe 3.
A pair of left and right lower pipes 7 connects the lower end of the lower pipe 4 and the lower end of the down pipe 4 to form a body frame.

A pair of left and right front forks 8 are pivotally supported on the head pipe 2, and a front wheel 9 is pivotally supported at the lower end thereof. The front of the head pipe 2 is covered with a head cowl 10,
A handle 11 is provided above the head pipe 2 so as to expand left and right.

Left and right seat rails 12 extend rearward from the upper portion of the center pipe 6, and a back stay 13 is connected between the seat rail 12 and a lower portion of the center pipe 6.

A fuel tank 15 is mounted so as to straddle the main pipe 3 from above, and a seat 16 is provided behind the fuel tank 15 so as to be supported by a seat rail 12. Bracket provided at the bent part of center pipe 6
The front end is pivoted by 17 and the rear fork 18 extends rearward,
A rear wheel 19 is pivotally supported at the rear end.

A rear cushion 14 having an upper end pivotally attached to a pair of left and right brackets 6a projecting rearward from a cross pipe extending between the upper portions of the left and right center pipes 6 has a lower end pivotally attached to a rear fork 18, and a body frame. And a rear fork 18.

The engine 20 is supported between the down pipe 4 and the center pipe 6, and an exhaust pipe 22 extends forward from a front exhaust port 39 of a cylinder 21 of the engine 20,
The exhaust pipe 22 is curved, and the exhaust
Connected to 23. A canister 25 is provided on the left side of the exhaust pipe 22 extending from the cylinder 21.

A carburetor 31 connected to an intake pipe 30 extending rearward from a rear intake port of the cylinder 21
It is located on the rear right side of 21. And seat rail 12
An air cleaner 32 is disposed below the rear of the crankcase 24, and a connecting tube 33 connects the air cleaner 32 and the front carburetor 31.

On the other hand, on the left side of the cylinder 21, a negative pressure pump 35
Is provided, a secondary air extraction tube 36 extending from the air cleaner 32 is connected to a negative pressure pump 35, and a secondary air supply tube 37 further extends from the negative pressure pump 35 to
The lower part of the cylinder 21 is joined. A secondary air supply path 38 is formed in the side wall of the cylinder 21 from this connection part, and communicates with the exhaust port 39.

The negative pressure pump 35 is a diaphragm type pump and is operated by a negative pressure generated in the carburetor 31 through a negative pressure pipe 40 leading to the carburetor 31. That is, the diaphragm is intermittently operated by the negative pressure generated in the carburetor 31, the secondary air is taken out from the air cleaner 32, and the secondary air is supplied to the exhaust port 39 in accordance with the exhaust timing to purify the exhaust.

A breather tube for reducing blow-by gas is provided from the upper rear of the crankcase 24 of the engine 20.
45 extends upward and is connected to a separator 46 located on the left side of the carburetor 31, and a breather tube 47 further downstream from the separator 46 extends and is joined to the air cleaner 32.

The liquid gas-liquid separated by the separator 46 is returned to the breather tube 45 on the upstream side by the return tube 48, and the gas is sent to the carburetor 31 for re-combustion to mainly reduce HC.

As described above, the air cleaner 32 to which the secondary air extraction tube 36 and the breather tube 47 are joined.
Is an air cleaner case 32 as shown in FIGS.
a has an air inlet 50 at the rear of the upper wall, a left side wall is a lid member 53 which can be opened and closed, and an element 52 is detachably attached so as to close the oblong opening 51 of the front wall from the inside. The element 52 can be taken in and out from the side with the lid member 53 removed.

The connecting tube 33 is joined to the opening 51 of the front wall. The shape of the connecting tube 33 is shown in FIGS.

The connecting tube 33 is an air cleaner of the curved tubular connecting tube body 55.
The opening 56 on the 32 side bulges out in the lateral direction to form an elliptical opening, and the periphery of the opening 56 extends outward to provide a flange 57.

The flange 57 has a groove 58 at the center in the circumferential direction.
Are formed, and bolt holes 59 are drilled at six places around. The connecting tube main body 55 extends forward while curving inward from the right half of the oval opening 56, and the tip thereof is connected to the carburetor 31.

On the other hand, the left half of the opening 56 bulges forward to form a sub-chamber 60, and the central side wall of the sub-chamber 60 is continuously curved to the curved inner wall of the connecting tube main body 55. The rear cushion 14 vertically penetrates the inside of the curved inner wall surface of the connecting tube main body 55 and the sub-chamber 60. In FIG. 6, the position of the rear cushion 14 is shown by a virtual line (two-dot chain line).

That is, the connecting tube main body 55
Extends frontward while curving so as to avoid the rear cushion 14 to the right from the oval opening 56,
Reference numeral 60 is curved so as to avoid the rear cushion 14 to the left from the oval opening 56 and slightly bulges forward.

The sub-chamber 60 has upper and lower cylindrical openings 61 and 62 formed therein. The upper cylindrical opening 61 is connected to the breather tube 47 for reducing blow-by gas.
The secondary air extraction tube 36 is connected to the lower cylindrical opening 59.

In the sub-chamber 60, a partition plate 63 is formed which defines a side for taking in the blow-by gas from the cylindrical opening 58 and a side for supplying the secondary air to the cylindrical opening 62. It does not flow to the air supply side.

In order to connect the rubber connecting tube 33 having the above configuration to the front opening 51 of the air cleaner case 32a, first, the air cleaner case 32a is connected.
Opening on the connecting tube 33 side around the periphery of the opening 51 on the side
The groove 58 formed in the peripheral flange 57 of 56 is fitted to communicate the internal space of the connecting tube main body 55 and the sub-chamber 60 with the inside of the air cleaner case 32a.

The inner periphery of the opening 51 on the side of the air cleaner case 32a has a circular hole corresponding to the bolt hole 59 provided in the flange 57 of the connecting tube 33, and a hollow element support is provided on the inner periphery of the opening 51. A plate 65 is abutted from the inside, and a bolt 66 that fits into the circular hole and the bolt hole 59 is fixed to the element support plate 65, and the bolt 66 passes through the bolt hole 59 and is screwed outward. To protrude.

A frame member 67 is applied from the outside to the outer flange 57 of the connecting tube 33 from which the bolt 66 protrudes, and a nut 68 is screwed into a screw portion of the bolt 66 passing through the frame member 67 and tightened. In this way, the connecting tube 33 is connected to the air cleaner case 32a, and the element support plate 65 is provided with a hook 69 for fixing the element 52, and the element 52 is detachably fixed to the element support plate 65 via a seal member 70. I do.

As described above, since the sub-chamber 60 is provided on the clean side of the air cleaner 32 and the secondary air is taken in from the sub-chamber 60 and supplied to the exhaust port 39, a volume chamber having a capacity is provided on the secondary air intake side. And the exhaust gas purification rate can be improved. Since the sub-chamber 60 is formed integrally with the connecting tube main body 55, the number of components can be reduced and the assembling is easy without providing a separate sub-chamber.

Similarly, since the breather tube 47 is connected to the sub-chamber 60 integrated with the connecting tube main body 55, the breather tube 47 has excellent assemblability together with the secondary air extraction tube 36.

The engine 20 and the rear cushion 14 are interposed.
, The air cleaner 32 is located rearward, and the air cleaner 3
Connecting tube connected to the opening 51 in the front wall 2
33, the main body 55 moves forward on the right side of the rear cushion 14.
Extend and connect to carburetor 31, connecting tube
The sub-chamber 60 formed integrally with the
Secondary air is extracted by expanding the left side of the cushion 33 forward.
Since it is connected to the tube 36, the rear cushion 14
Connecting Chu using the free space around
The main body 55 and the sub-chamber 60 are provided,
That the intake system can be assembled compactly
In the meantime, the air cleaner 32 is placed close to the rear cushion 14.
The overall length of the vehicle body can be kept small.

[0034]

According to the present invention, an empty space around the rear cushion is provided.
Compact air intake system for vehicle body using space
And the air cleaner at the rear.
It is possible to approach the cushion and keep the overall length of the vehicle small
it can. Integrally formed on the connecting tube
Since the secondary air extraction tube is connected to the
Good assemblability.

By connecting a breather tube for reducing blow-by gas to the sub-chamber, it is possible to maintain a high assembling property.

[Brief description of the drawings]

FIG. 1 is an overall side view of a motorcycle according to one embodiment of the present invention.

FIG. 2 is a side view of a main part of the motorcycle with a part omitted.

FIG. 3 is a perspective view of an air cleaner and a connecting tube.

FIG. 4 is a side view showing an internal structure of the air cleaner and a connecting tube.

FIG. 5 is a side view of the connecting tube.

6 is a sectional view taken along line VI-VI in FIG.

FIG. 7 is a view taken in the direction of the arrow VII in FIG. 5;

8 is a sectional view taken along line VIII-VIII in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 2 ... Head pipe, 3 ... Main pipe, 4 ... Down pipe, 5 ... Reinforcement stay, 6 ... Center pipe, 7 ... Lower pipe, 8 ... Front fork, 9 ...
Front wheel, 10 ... Head cowl, 11 ... Handle, 12 ... Seat rail, 13 ... Back stay, 14 ... Rear cushion, 15 ... Fuel tank, 16 ... Seat, 17 ... Bracket, 18 ... Rear fork, 19 ... Rear wheel, 20 ... Engine, 21 ... Cylinder, 22 ... Exhaust pipe, 23 ... Muffler, 24 ... Crankcase, 25 ... Canister, 30 ... Intake pipe, 31 ... Carburetor, 32 ... Air cleaner, 33 ... Connecting tube, 35 ... Negative pressure pump, 36
... secondary air outlet tube, 37 ... secondary air supply tube,
38 ... secondary air supply path, 39 ... exhaust port, 40 ... negative pressure pipe, 45 ... breather tube, 46 ... separator, 47 ... breather tube, 48 ... return tube, 50 ... air intake, 51
... Opening, 52 ... Element, 53 ... Lid, 55 ... Connecting tube body, 56 ... Opening, 57 ... Flange, 58 ... Groove,
59 ... bolt hole, 60 ... sub-chamber, 61, 62 ... cylindrical opening, 63 ... partition plate, 65 ... element support plate, 66 ... bolt, 67 ... frame member, 68 ... nut, 69 ... hook, 70 ... sealing material .

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location F02M 35/10 311 F02M 35/10 311Z

Claims (2)

(57) [Claims] 1. An engine is arranged between a front wheel and a rear wheel,
Rear almost vertically oriented close to the rear of the engine
Arrange the cushion, and place the air cushion behind the rear cushion.
In a motorcycle having a structure in which a cleaner is disposed and having a secondary air introduction device for purifying exhaust gas , a connecting tube is provided at a front wall opening of the air cleaner.
And the connecting tube body is connected to the rear cushion.
The front end is connected to the carburetor by extending one side to the front, and a sub-ch is formed integrally with the connecting tube.
Chamber bulges the other side of the rear cushion forward
A suction device for a motorcycle , wherein a secondary air extraction tube is connected to the sub-chamber. 2. The motorcycle air intake system according to claim 1, wherein a breather tube for reducing blow-by gas is connected to the sub-chamber.