JP2001130475A - Scooter type vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scooter type vehicle capable of sufficiently assuring the capacity of an article storing compartment. SOLUTION: This scooter type vehicle comprises an engine 102, a transmission case 48 formed integrally with the engine and extending rearward from one side of the engine 102 and transmitting a driving force to a rear wheel 50 held by the rear end of the engine 102 a swing type power unit 101 supported swingably and elastically on a body frame, and an article storing compartment provided on the body frame. The entire vehicle body is covered with a body cover. The swing type power unit 101 is formed by disposing the cylinder head 105, engine intake system 119, and engine exhaust system 96 of the engine 102 on the side opposite to the transmission case 48 with respect to the axis 54 of a vehicle forward moving direction. The engine intake system 119 is connected to the upper side of the cylinder head 105, and the engine exhaust system 96 is connected to the lower side of the cylinder head 105. On the other hand, the engine exhaust system 119 is disposed in a space formed on the side opposite to the transmission case 48 across a rear wheel 50 located at the rear of the cylinder head 105.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a scooter type vehicle.

[0002]

2. Description of the Related Art Many scooter type vehicles have a swing type power unit. The swing type power unit is integrally provided with an engine and a transmission case internally provided with a transmission that extends rearward from one side of the engine, and is swingably provided on a body frame or the like.

As an example of a swing type power unit in which an engine is arranged substantially horizontally and its cylinder is arranged in parallel with the traveling direction of a vehicle, those disclosed in, for example, JP-A-62-155185 and JP-A-6-48342 are disclosed. There is.

Japanese Patent Application Laid-Open No. Sho 61-61 discloses an example in which cylinders are arranged in a direction perpendicular to the traveling direction of a vehicle.
No. 8,188,841 or JP-A-63-106194, as well as French Patent 1.133.249.
There are the following.

As a cooling method of the engine, for example, as shown in Japanese Patent Application Laid-Open No. Hei 6-200757, a heat radiating portion of the engine is covered with a shroud, and cooling air is blown from a cooling air intake through a fan driven by the engine. There is a forced air-cooled type that is guided into the shroud.

FIG. 16 is a side view showing a general example of a forced air-cooled swing type power unit in which an engine is arranged substantially horizontally and a cylinder thereof is arranged in parallel with a traveling direction axis of a vehicle. FIG. Horizontal sectional view (A in FIG. 16)
FIG. 2 is a cross-sectional view taken along line -A).

As shown in FIGS. 16 and 17, the swing type power unit 1 is swingably connected to a body frame 2 via a stay 3 so as to be swingable.

An engine 4 is arranged at the front of the swing type power unit 1. This engine 4
It is mainly composed of a crankcase 5, a cylinder 6, and a cylinder head 7, and a reciprocating stroke of a piston 9 in the cylinder 6 arranged in parallel with a traveling direction axis 8 of the vehicle rotates a crankshaft 11 via a connecting rod 10. Exercise. Crankshaft 11
Are disposed in the crankcase 5 in the vehicle width direction (the direction orthogonal to the traveling direction axis 8 of the vehicle), and a pair of bearings 12
Supported by Further, for example, a conduction case 13 is provided on the left side of the engine 4.

A drive pulley 15 of a V-belt transmission mechanism 14 provided in a transmission case 13 is attached to the left end side of the crankshaft 11. The drive pulley 15 of the V-belt transmission mechanism 14 is driven via a V-belt 16. Pulley 1
7, the driving force of the engine 4 is transmitted.

The driven pulley 17 is transmitted to a rear wheel drive shaft 21 via a centrifugal clutch mechanism 18, a driven shaft 19 and an idle shaft 20 provided at the rear of the swing type power unit 1. The driving force of the engine 4 is transmitted to a rear wheel 22 fixed to the drive shaft 21.

On the other hand, an exhaust pipe 23a constituting an engine exhaust system 23 is provided on the lower surface of the cylinder 6 of the engine 4.
A muffler 23b is connected downstream of the exhaust pipe 23a, and a carburetor 24 constituting an engine intake system 24 is provided on the back of the crankcase 5.
a and the air cleaner 24b are connected. The article storage room 2 is located above the engine intake system 24.
5 are arranged.

The engine 4 employs a forced air cooling type cooling system, and a shroud 2 is provided around the engine 4.
The cooling air is introduced into the shroud 26 through a cooling air inlet 28 by a fan 27 provided at the right end of the crankshaft 11.

Reference numeral 29 denotes a spark plug connected to the cylinder head 7.

[0014]

However, when the crankshaft is arranged in the vehicle width direction (the direction perpendicular to the vehicle traveling direction axis) in the crankcase, the crankshaft cantilever on the drive pulley side of the V-belt transmission mechanism. As the length becomes longer, a load is applied to the bearing, which is likely to cause troubles in the bearing portion, and is disadvantageous for the vibration of the V-belt.

If a fan is provided at the right end of the crankshaft, the cooling air intake is inevitably opened toward the outside of the vehicle, and the noise generated when the cooling air is sucked is transmitted to the rider and passers-by. Cheap.

Furthermore, if the cylinder is arranged in parallel with the traveling direction axis of the vehicle, the position of the ignition plug is located at the lower front part of the article storage chamber, and maintenance is difficult.

Similarly, the connecting portion of the exhaust pipe to the cylinder is located on the center line of the vehicle, and it is difficult to attach and detach the exhaust pipe.

Furthermore, when the engine is a two-stroke engine, the flow of the air-fuel mixture to the scavenging port can be made equal to the left and right by arranging the valve opposite to the piston. On the contrary, the front of the rear wheel was approaching, and the valve had to be located elsewhere.

Further, due to the layout of the swing type power unit, the engine intake system can be arranged only between the back of the swing type power unit and the bottom of the article storage room.
Therefore, the capacity of the storage room is limited, and it is difficult to flatten the bottom surface of the storage room.

When the engine is provided with a balancer device, it is desirable that the balancer shaft be disposed in parallel with the crankshaft. However, the rear portion of the crankshaft is close to the front portion of the rear wheel, and there is not enough space. ,
If the balancer device is arranged above the crankshaft, it may interfere with the bottom surface of the storage chamber as described above, and if the balancer device is arranged below the crankshaft, the minimum ground clearance decreases, which is not preferable.

The present invention has been made in view of the above-described circumstances, and has as its object to provide a scooter-type vehicle capable of sufficiently securing the capacity of an article storage room.

Another object of the present invention is to provide a scooter type vehicle which facilitates maintenance.

Still another object of the present invention is to provide a scooter-type vehicle in which noise generated when cooling air is sucked is hardly transmitted to a rider or a pedestrian.

Another object of the present invention is to provide a scooter type vehicle equipped with a two-cycle engine capable of equally distributing the flow of the air-fuel mixture to the scavenging port.

Still another object of the present invention is to provide a scooter type vehicle capable of securing a space for disposing a balancer device.

Another object of the present invention is to provide a scooter type vehicle capable of reducing the length of a cantilever portion of a crankshaft.

[0027]

According to a first aspect of the present invention, there is provided a scooter-type vehicle, comprising: an engine; A rear case held at the end is integrally provided with a conduction case for transmitting a driving force, a swing type power unit swingably and elastically supported on the body frame, and an article storage chamber on the body frame. In the scooter-type vehicle, the entire vehicle body of which is covered with a vehicle body cover, the swing type power unit includes a cylinder head of the engine, an engine intake system, and an engine exhaust system on a side of the traveling direction axis of the vehicle opposite to the transmission case. The engine intake system above the cylinder head and the engine exhaust system below the cylinder head. While connected, in which the engine intake system disposed in a space which is formed opposite to the conductive casing by sandwiching the rear wheel of the rear above the cylinder head.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a left side view showing a first embodiment of a scooter type vehicle to which the present invention is applied, and FIG.
The right side. Further, FIG. 3 is a cross-sectional view of FIG.
FIG. 4 is a sectional view taken along the line IV-IV of FIG. 1.

As shown in FIGS. 1 to 4, this scooter type vehicle 30 has a body frame 31. The body frame 31 includes a down tube 32 and a pair of left and right rear frames 33 extending rearward and upward from the rear end of the down tube 32. An article storage room 35 capable of storing a helmet 34 and the like is provided above the rear frame 33, and a driving seat 36 is installed above the article storage chamber 35 so as to be openable and closable, and behind the article storage chamber 35. For example, a fuel tank 37 is arranged. As shown in FIG. 1, for example, the entire body of the scooter-type vehicle 30 including the article storage room 35 is covered with a synthetic resin body cover 38, and the appearance of the vehicle is adjusted.

A head pipe 39 is provided at the front end of the down tube 32, and a front fork 41 and a handle bar 42 for rotatably supporting the front wheel 40 are provided on the head pipe 39. And this handlebar 42
Thereby, the front wheel 40 is steerably rotatable left and right.

On the other hand, a pair of left and right suspension brackets 43 is provided at the center of the rear frame 33. A pivot shaft 44 is provided between the suspension brackets 43, and a swing type power unit 45 is attached to the pivot shaft 44 by a stay 4.
6 is pivotally connected via a swing.

The swing type power unit 45 (hereinafter simply referred to as a power unit) includes an engine 47,
Conductive case 4 extending rearward from one side of this engine 47
8 are provided integrally. The transmission case 48 also serves as a swing arm, and is elastically supported by the rear frame 33 by a rear shock absorber 49. Then, a rear wheel 50 as a driving wheel is held at the rear end of the transmission case 48.

An engine 4 is provided in front of the power unit 45.
7 are arranged. The engine 47 is an air-cooled two-cycle single-cylinder engine, and mainly includes a crankcase 51, a cylinder 52, and a cylinder head 53. The above-described stay 46 for suspending the power unit is provided on the outer wall of the crankcase 51. For example, as clearly shown in FIG. 1, the pivot shaft 44 is set to be substantially the same height as the upper portion of the engine 47. Is done.

As shown in FIG. 3, on one side of the traveling direction axis 54 of the vehicle 30, for example, on the right side of the crankcase 51, the cylinder 52 is disposed in a direction perpendicular to the traveling direction axis 54 of the vehicle 30 and substantially horizontally. Is done. A combustion chamber 55 is formed in a cylinder head 53 joined to the cylinder 52 so as to match the cylinder 52, and a spark plug 56 is screwed to the center of the combustion chamber 55 from outside.

The crankcase 51 can be divided into left and right along the traveling direction axis 54 of the vehicle 30, and a crankshaft 57 is arranged on the mating surface in parallel with the traveling direction axis 54 of the vehicle 30. The crankshaft 57 is configured to be splittable back and forth, is connected at an intermediate portion by a crankpin 58, and is supported by a pair of bearings 59.

A piston 61 is connected to the crank pin 58 via a connecting rod 60, and the reciprocating motion of the piston 61 in the cylinder 52 causes the crank shaft 57 to rotate. The crank chamber 62 in which the crankshaft 57 in the crankcase 51 is disposed and the inside of the cylinder 52 are communicated by a scavenging passage 63.

On the front side of the crankcase 51, a magneto device 64 is provided. A flywheel magneto 65 constituting a magneto device 64 is fixed to the tip of the crankshaft 57 so as to rotate integrally therewith, and a cooling fan 66 is rotatably fixed to the front surface thereof.

The cylinder 52 which is a heat radiating part of the engine 47
A cooling fin 67 is formed on the cylinder head 53 and the cylinder 52 and the cylinder head 53 are formed.
Is covered by a shroud 68. In the shroud 68, a cooling air inlet 69 is formed in the lower part of the article storage chamber 35 and opens in the traveling direction of the vehicle 30.

An oil pump drive gear 70 is provided at a rear portion of the crankshaft 57, and is configured to drive an oil pump 72 disposed on the back of the crankcase 51 via the oil pump drive shaft 71.
At the rear end of the crankshaft 57, there is provided a drive bevel gear 73 which is a transmission device for transmitting the driving force of the engine 47 while changing the rotation axis of the crankshaft 57 in a different direction.

On the other hand, an idle shaft chamber 74 is formed between the crank chamber 62 and the front portion of the rear wheel 50. In the idle shaft chamber 74, a crank idle shaft 7 is provided.
5 are arranged in a direction orthogonal to the crankshaft 57,
It is supported by bearings 76.

A driven bevel gear 77, which is a transmission device for transmitting the driving force of the engine 47 while converting the rotation axis of the crankshaft 57 in a different direction, is provided near the intermediate portion of the crank idle shaft 75. Is configured to change the rotation axis direction of the crankshaft 57 by meshing with the drive bevel gear 73.

The idle shaft chamber 74 is provided with an idle shaft cover 7 for supporting the crank idle shaft 75.
Blocked by 8. Both bevel gears 73 and 73 are provided on the joint surface between the idle shaft chamber 74 and the idle shaft cover 78.
A shim 79 for adjusting the engagement of 77 is provided,
The crank chamber 62 and the idle shaft chamber 74 are kept liquid-tight by the O-ring 80 and the like.

As clearly shown in FIG.
The transmission case 48 is disposed on the opposite side of the cylinder 52 with respect to the zero traveling direction axis 54. The conductive case 48 is covered by a case cover 81 and has a belt chamber 82 therein.
The V-belt type automatic transmission 83 is disposed in the belt chamber 82.

The left end of the crank idle shaft 75 projects into the belt chamber 82, and a drive pulley 84 of a transmission 83 is mounted. Drive pulley 84 is V
The driving force of the engine 47 is transmitted to the driven pulley 86 via the belt 85.

The driven pulley 86 is connected to the power unit 4
5, is rotatably supported by a driven shaft 87 provided at the rear of the engine 5, and the rotational driving force from the engine 47 transmitted to the driven pulley 86 is a centrifugal clutch mechanism 88.
Is transmitted to the driven shaft 87 via the

The driven shaft 87 is connected to a rear wheel drive shaft 90 through a transmission mechanism 89 which is a reduction gear mechanism and a power transmission device.
The driving force of the engine 47 is transmitted to the rear wheel 50 through the drive wheels 9.

Incidentally, a portion of the crankcase 51 opposite to the piston 61, for example, the crankcase 51
A reed valve 92, which is a valve device constituting an engine intake system 91, is provided on the left side of the valve.
The carburetor 9 also constitutes the engine intake system 91 in FIG.
3 is connected via an intake pipe 94. An air cleaner 95, which also forms an engine intake system 91, is connected to the upstream side of the carburetor 93. The air cleaner 95 is arranged in a space formed between the left side surface of the crankcase 51 and the front surface of the conduction case 48 and below the article storage chamber 35.

On the other hand, an exhaust pipe 9 constituting an engine exhaust system 96 is provided on the lower surface of the cylinder 52 of the engine 47.
7 is connected, and a muffler 98 is connected downstream of the exhaust pipe 97.

As described above, the cylinder 52 is connected to the vehicle 30
The connection portion of the ignition plug 56 and the exhaust pipe 97 is located on the side of the vehicle 30 and can be easily attached and detached, thereby improving the maintainability.

The crankshaft 57 is arranged parallel to the traveling direction axis 54 of the vehicle 30 and a crank idle shaft 75 is provided. The shafts 57, 75 are connected by bevel gears 73, 77, and the rotation shaft of the crankshaft 57 is rotated. By changing the direction, not only the cantilever portion 57a of the crankshaft 57 but also the length of the crank idle shaft 75 is reduced, so that the bearing 5
9, 76 is less likely to be burdened. As a result, the trouble of the bearing portion is reduced, and the vibration of the V-belt 85 is advantageous.

Further, by disposing the cylinder 52 in a direction orthogonal to the traveling direction axis 54 of the vehicle 30, a shroud 68 covering the cylinder 52 and the cylinder head 53 is provided.
Can be opened in the traveling direction of the vehicle 30. As a result, noise generated when the cooling air is sucked is not directly transmitted to the rider or the pedestrian. In addition, since the exhaust air of the cooling air hits the exhaust pipe 97, the cooling efficiency of the exhaust pipe 97 is also improved.

Further, by disposing the cylinder 52 in a direction perpendicular to the traveling direction axis 54 of the vehicle 30, the cylinder 52 is located between the left side surface of the crankcase 51 and the front surface of the transmission case 48 and below the article storage chamber 35. Space is formed,
The engine intake system 91 can be arranged in this space.
As a result, the reed valve 92 can be disposed directly opposite to the piston 61, so that the flow of the air-fuel mixture to the scavenging passage 63 can be equalized in the left and right directions, and there is sufficient space between the back surface of the power unit 45 and the bottom surface of the article storage chamber 35 A sufficient space can be secured, and the bottom surface of the article storage chamber 35 can be flattened, so that the volume of the article storage chamber 35 can be sufficiently ensured.

In the above-described embodiment, the example in which the bevel gears 73 and 77 are used as the transmission device for transmitting the driving force of the engine 47 while changing the rotation axis of the crankshaft 57 in a different direction has been described. Regardless of the bevel gears 73 and 77, a hypoid gear or the like can be used.

In the above embodiment, the stay 46 for suspending the power unit is provided above the outer wall of the crankcase 51. However, as shown in FIGS. 5 and 6, the stay 46 is connected to the outer wall of the crankcase 51. And the power unit 45 may be pivotally attached to the rear end of the down tube 32.

Further, in the above-described embodiment, an example is shown in which the air cleaner 95 is arranged in a space formed between the left side surface of the crankcase 51 and the front surface of the transmission case 48 and below the article storage chamber 35. As shown in FIG. 6, the air cleaner 95 may be disposed on the case cover 81 of the conduction case 48.

FIG. 7 is a left side view showing a second embodiment of a scooter type vehicle to which the present invention is applied, and FIG.
The right side. 9 is a cross-sectional view taken along line IX-IX of FIG. 7, and FIG. 10 is a cross-sectional view taken along line XX of FIG. Note that the scooter type vehicle 1 of the second embodiment is
Since 00 is basically the same as the scooter type vehicle 30 shown in the first embodiment, the same components are denoted by the same reference numerals.

As shown in FIGS. 7 to 10, this scooter type vehicle 100 has a body frame 31. The body frame 31 includes a down tube 32 and a pair of left and right rear frames 33 extending rearward and upward from the rear end of the down tube 32. Also, the rear frame 33
The article storage room 3 which can store the helmet 34 etc.
A driving seat 36 is provided above the article storage room 35.
Is installed so as to be openable and closable, and, for example, a fuel tank 37 is disposed behind the article storage chamber 35. As shown in FIG. 7, for example, the entire body of the scooter type vehicle 100 including the article storage room 35 is covered with a vehicle body cover 38 made of synthetic resin, so that the appearance of the vehicle is adjusted.

A head pipe 39 is provided at the front end of the down tube 32, and a front fork 41 and a handle bar 42 for rotatably supporting the front wheel 40 are provided on the head pipe 39. And this handlebar 42
Thereby, the front wheel 40 is steerably rotatable left and right.

On the other hand, a pair of left and right suspension brackets 43 is provided at the center of the rear frame 33. A pivot shaft 44 is provided between the suspension brackets 43, and a swing type power unit 101 is swingably connected to the pivot shaft 44 via a stay 46.

The swing type power unit 101 (hereinafter simply abbreviated as a power unit) is an engine 102.
And a transmission case 48 extending rearward from one side of the engine 102. The transmission case 48 also serves as a swing arm, and is provided with the rear shock absorber 4.
9 supports the rear frame 33 elastically. Then, a rear wheel 50 as a driving wheel is held at the rear end of the transmission case 48.

An engine 102 is arranged in front of the power unit 101. The engine 102 is an air-cooled 4-cycle single-cylinder engine, and mainly includes a crankcase 10.
3, a cylinder 104, a cylinder head 105 and a head cover 106. The stay 46 for suspending the power unit is connected to the crankcase 103.
Provided on the upper part of the outer wall, for example, as clearly shown in FIG. 7, the pivot shaft 44 is set to be substantially the same height as the upper part of the engine 102.

As shown in FIG. 9, the traveling direction axis 54 of the vehicle
On one side, for example, on the right side of the crankcase 103, a cylinder 104 is disposed in a direction perpendicular to the traveling direction axis 54 of the vehicle 100 and substantially horizontally. Also, this cylinder 10
4 has the cylinder 1
A combustion chamber 55 is formed so as to match the ignition plug 04, and a spark plug 56 is screwed from the outside. Furthermore, cylinder head 1
A valve mechanism 108 including an intake / exhaust valve (not shown) and a cam shaft 107 for opening and closing these valves is disposed above the valve 05. The valve mechanism 108 is covered by a head cover 106.

The crankcase 103 can be divided into left and right along the traveling direction axis 54 of the vehicle 100.
And are arranged in parallel. The crankshaft 57 is configured to be splittable back and forth, is connected at an intermediate portion by a crankpin 58, and is supported by a pair of bearings 59.

A piston 61 is connected to the crank pin 58 through a connecting rod 60, and the reciprocating motion of the piston 61 in the cylinder 104 causes the crank shaft 57 to rotate.

A cam chain drive sprocket 109 is provided at the front of the crankshaft 57. Also,
A cam chain driven sprocket 110 is provided at the front of the cam shaft 107, and both sprockets 109,
110 are connected by a cam chain 111. A cam chain chamber 112 is formed at the front side of the cylinder 104 and the cylinder head 105, and the cam chain 111 is housed therein.

A magneto device 64 is provided on the front side of the crankcase 103. A flywheel magneto 65 constituting a magneto device 64 is fixed to the tip of the crankshaft 57 so as to rotate integrally therewith, and a cooling fan 66 is rotatably fixed to the front surface thereof.

Cylinder 1 which is a heat radiation part of engine 102
Cooling fins 67 are formed on the cylinder head 104 and the cylinder head 105, and the cylinder 104 and the cylinder head 105 are covered with a shroud 68. In the shroud 68, a cooling air intake 69 is formed below the article storage chamber 35 and opens in the traveling direction of the vehicle 100.

At the rear of the crankshaft 57, a starter gear 114 is provided via a starter clutch 113, and the crankcase 103 is provided via an idle gear 115.
It is operatively connected to a drive shaft 117 of a starter motor 116 disposed on the back. At the rear end of the crankshaft 57, there is provided a drive bevel gear 73 which is a transmission device for transmitting the driving force of the engine 102 while changing the rotation axis of the crankshaft 57 in a different direction.

On the other hand, an idle shaft chamber 74 is formed between the crankcase 62 of the crankcase 103 in which the crankshaft 57 is housed and the front portion of the rear wheel 50. A crank idle shaft 75 is disposed in the idle shaft chamber 74 in a direction orthogonal to the crank shaft 57 and supported by bearings 76.

A driven bevel gear 77, which is a transmission device for transmitting the driving force of the engine 102 while converting the rotation axis of the crankshaft 57 in a different direction, is provided near the intermediate portion of the crank idle shaft 75. Is configured to change the rotation axis direction of the crankshaft 57 by meshing with the drive bevel gear 73.

The idle shaft chamber 74 is provided with an idle shaft cover 7 for supporting the crank idle shaft 75.
Blocked by 8. Both bevel gears 73 and 73 are provided on the joint surface between the idle shaft chamber 74 and the idle shaft cover 78.
A shim 79 for adjusting the engagement of 77 is provided,
The crank chamber 62 and the idle shaft chamber 74 are kept liquid-tight by the O-ring 80 and the like.

As clearly shown in FIG. 9, the vehicle 1
The transmission case 48 is arranged on the opposite side of the cylinder 104 with respect to the traveling direction shaft 54 of 00. Conduction case 48
Is covered by a case cover 81 to form a belt chamber 82 therein, in which a V-belt type automatic transmission 83 is disposed.

The left end of the crank idle shaft 75 projects into the belt chamber 82, and the drive pulley 84 of the transmission 83 is mounted. The drive pulley 84 is connected to a driven pulley 86 via a V-belt 85,
The driving force of the engine 102 is transmitted to the driven pulley 86.

The driven pulley 86 is connected to the power unit 1
The rotational driving force from the engine 102 transmitted to the driven pulley 86 is transmitted to the driven shaft 87 via the centrifugal clutch mechanism 88.

The driven shaft 87 is connected to a rear wheel drive shaft 90 through a transmission mechanism 89 which is a reduction gear mechanism and a power transmission device.
The driving force of the engine 102 is transmitted to the rear wheels 50 via the drive wheels 9.

On the other hand, an exhaust pipe 97 constituting the engine exhaust system 96 is connected to an exhaust passage 118 on the lower surface of the cylinder head 105.
The muffler 98 is connected to the downstream side. As clearly shown in FIG. 10, the minimum ground clearance of the exhaust pipe 97 is set to be substantially the same as the minimum ground clearance of the engine 102 or the transmission case 48.

A carburetor 120 constituting an engine intake system 119 is arranged near the cylinder head 105 and on the opposite side of the cam chain chamber 112 and connected to an intake passage 122 on the upper surface of the cylinder head 105 via an intake pipe 121. You.

Further, an air cleaner 123 similarly constituting the engine intake system 119 is connected to the upstream side of the carburetor 120. The air cleaner 123 is disposed in a space formed at the rear of the cylinder 104 and the cylinder head 105 and above the muffler 98 and on the opposite side of the transmission case 48 with the rear wheel 50 interposed therebetween, as clearly shown in FIG. Is done.

A breather hose 124 is attached to the wall of the idle shaft chamber 74,
The blow-by gas accumulated in the inside is guided to the air cleaner 123. The breather hose 124 may be provided on the upper wall or the side wall of the crankcase 103 near the crankshaft 57.

As described above, the cylinder 104 is mounted on the vehicle 1
By arranging in the direction perpendicular to the traveling direction axis 54 of 00, the connection portion of the ignition plug 56 and the exhaust pipe 97 is located on the side of the vehicle 100, and can be easily attached and detached, thereby improving maintainability.

The crankshaft 57 is connected to the vehicle 100
And a crank idle shaft 75 is provided, and both shafts 57, 75 are connected by bevel gears 73, 77 so as to change the rotation axis direction of the crankshaft 57. Not only the cantilever portion 57a of the crankshaft 57 but also the length of the crank idle shaft 75 is shortened, so that the bearings 59 and 76 are less likely to be burdened. As a result, the trouble of the bearing portion is reduced, and the vibration of the V-belt 85 is advantageous.

Further, by disposing the cylinder 104 in a direction perpendicular to the traveling direction axis 54 of the vehicle 100, the cooling air intake 69 of the shroud 68 covering the cylinder 104 and the cylinder head 105 is moved toward the traveling direction of the vehicle 100. Opening is possible. As a result, noise generated when the cooling air is sucked is not directly transmitted to the rider or the pedestrian.

Further, the cylinder 104 is mounted on the vehicle 100
A space is formed at the rear of the cylinder 104 and the cylinder head 105, above the muffler 98, and to the right of the rear wheel 50 by disposing the engine intake system 119 in this space. It can be arranged. As a result, a sufficient space can be secured between the back surface of the power unit 101 and the bottom of the article storage chamber 35, and the bottom of the article storage chamber 35 can be flattened, and the volume of the article storage chamber 35 can be sufficiently secured.

In the above-described embodiment, the example has been described in which the bevel gears 73 and 77 are used as the transmission device for transmitting the driving force of the engine 102 while changing the rotation axis of the crankshaft 57 to a different direction. Regardless of the bevel gears 73 and 77, a hypoid gear or the like can be used.

Further, in the above-described embodiment, an example is shown in which the stay 46 for suspending the power unit is provided above the outer wall of the crankcase 103. However, FIG.
As shown in (2), the stay 46 may be provided below the outer wall of the crankcase 103, and the power unit 101 may be pivotally attached to the rear end of the down tube 32.

Further, in the above-described embodiment, the engine intake system 119 is provided in a space formed at the rear of the cylinder 104 and the cylinder head 105, above the muffler 98, and on the opposite side of the transmission case 48 with the rear wheel 50 therebetween. Although the example of arrangement is shown, as shown in FIG. 11, the engine intake system 119 is connected to the cylinder 104 and the cylinder head 1.
The air cleaner 123 may be disposed in a space formed between the left side surface of the crankcase 103 and the front surface of the transmission case 48 and below the article storage chamber 35 as shown in FIG. May be arranged, and the air cleaner 123 and the carburetor 120 may be connected using the duct 125.

FIG. 13 is a left side view of the power unit 126 showing an example in which the balancer device 127 is provided in the engine 102 used in the second embodiment described above, and FIG. 14 is taken along the line XIV-XIV in FIG. It is sectional drawing.

As shown in FIGS. 13 and 14, the balancer device 127 includes a crankcase 1 on the front surface of the transmission case 48.
03 on the left side. This balancer device 127 includes:
A balancer shaft 129 arranged parallel to the crankshaft 57 and supported by a pair of bearings 128
A balancer weight 130 fixed to the balancer shaft 129; and a balancer driven gear 13 provided at one end of the balancer shaft 129 and meshing with a balancer drive gear 131 provided on the crankshaft 57.
And 2. Also, this balancer device 127
Is an opening 1 formed on the left side of the crankcase 103.
The opening 133 is closed by a balancer cover 134.

As described above, the cylinder 104 is mounted on the vehicle 1
By arranging the balancer shaft 129 in a direction orthogonal to the traveling direction axis 54 of the 00, the balancer shaft 129 can be arranged parallel to the crankshaft 57 at a position that does not interfere with other members.

In the above-described embodiment, an example is shown in which the breather hose 124 is mounted on the wall of the idle shaft chamber 74 or on the upper wall or side wall of the crankcase 103. However, as shown in FIGS.
The breather hose 124 may be mounted near the position 27, for example, on the balancer cover 134.

Further, in the two-cycle engine 47 shown in the first embodiment, the crankshaft 57
An oil pump drive gear 70 is provided on the rear end side of the oil pump 7 and an oil pump 7
2 has been shown to be driven, for example, in FIG.
As shown in FIG. 5, the right end of the crank idle shaft 75 may be extended to the wall surface, and the oil pump 72 may be directly connected to the extended end 75a.

Further, 4 shown in the second embodiment described above.
In the cycle engine 102, the oil pump 72
The description of the two-stroke engine 47 is omitted.
Similarly, the extension end portion 75a of the crank idle shaft 75
It is also possible to connect an oil pump directly to the motor. In this case, an oil filter (not shown) may be arranged near the oil pump.

[0094]

As described above, according to the scooter type vehicle according to the present invention, the transmission case for transmitting the driving force to the engine and the rear wheel extending rearward from one side of the engine and held at the rear end thereof. A scooter type having a swing type power unit swingably and elastically supported on a body frame, and having an article storage room on the body frame, and covering the entire body with a body cover. In the vehicle, the swing type power unit includes a cylinder head of the engine, an engine intake system and an engine exhaust system disposed on a side opposite to the transmission case on an axis in a traveling direction of the vehicle, and connects the engine intake system to the cylinder head. On the upper side, the engine exhaust system is connected to the lower side of the cylinder head, while the engine intake system is connected to the cylinder head. Since it is located in the space formed on the opposite side of the conduction case with the rear wheel behind the dahead, sufficient space can be secured between the back of the power unit and the bottom of the article storage room, and the bottom of the article storage chamber is flattened. And the volume of the article storage room can be sufficiently secured.

[Brief description of the drawings]

FIG. 1 is a left side view of a scooter-type vehicle showing a first embodiment of a scooter-type vehicle according to the present invention.

FIG. 2 is a right side view of the scooter type vehicle shown in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1;

FIG. 5 is a left side view of the power unit showing another mounting position of the power unit suspension stay.

FIG. 6 is a left side view of the power unit showing another arrangement position of the air cleaner.

FIG. 7 is a left side view of the scooter type vehicle, showing a second embodiment of the scooter type vehicle according to the present invention.

FIG. 8 is a right side view of the scooter type vehicle shown in FIG.

FIG. 9 is a sectional view taken along the line IX-IX of FIG. 7;

FIG. 10 is a sectional view taken along the line XX of FIG. 7;

FIG. 11 is a plan view of the power unit showing another arrangement position of the engine intake system.

FIG. 12 is a plan view of the power unit showing another arrangement position of the engine intake system.

13 is a left side view of a power unit showing an example in which a balancer device is provided in the engine shown in FIG. 9;

FIG. 14 is a sectional view taken along the line XIV-XIV in FIG. 13;

FIG. 15 is a partial plan cross-sectional view of the power unit showing another arrangement position of the oil pump.

FIG. 16 is a side view showing a general example of a forced air-cooled swing type power unit in which an engine is arranged substantially horizontally and a cylinder thereof is arranged in parallel with a traveling direction axis of the vehicle.

FIG. 17 is a sectional view taken along the line AA of FIG. 16;

[Explanation of symbols]

 30, 100 Scooter type vehicle 31 Body frame 32 Down tube 33 Rear frame 35 Article storage room 45, 101, 126 Swing type power unit 47 Two-cycle engine 48 Transmission case 50 Rear wheel 51, 103 Crank case 52, 104 Cylinder 53, 105 cylinder Head 54 Vehicle traveling direction axis 56 Spark plug 57 Crankshaft 66 Cooling fan 68 Shroud 69 Cooling air intake 73 Drive bevel gear (transmission device) 75 Crank idle shaft 77 Driven bevel gear (transmission device) 83 V-belt automatic transmission 90 After Wheel drive shaft 91,119 Engine intake system 92 Reed valve (valve device) 93,120 Carburetor 96 Engine exhaust system 102 4-cycle engine 108 Valve train 11 1 cam chain 112 cam chain chamber 127 balancer device 129 balancer shaft

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[Procedure amendment]

[Submission date] January 22, 2001 (2001.1.2)
2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] Scooter type vehicle

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a scooter type vehicle.

[0002]

2. Description of the Related Art Many scooter type vehicles have a swing type power unit. The swing type power unit is integrally provided with an engine and a transmission case internally provided with a transmission that extends rearward from one side of the engine, and is swingably provided on a body frame or the like.

As an example of a swing type power unit in which an engine is arranged substantially horizontally and its cylinder is arranged in parallel with the traveling direction of a vehicle, those disclosed in, for example, JP-A-62-155185 and JP-A-6-48342 are disclosed. There is.

Japanese Patent Application Laid-Open No. Sho 61-61 discloses an example in which cylinders are arranged in a direction perpendicular to the traveling direction of a vehicle.
In addition to those disclosed in JP-A-81884 and JP-A-63-106194, French Patent 1.133.249
There are the following.

As a cooling method of the engine, for example, as shown in Japanese Patent Application Laid-Open No. Hei 6-200757, a heat radiating portion of the engine is covered with a shroud, and cooling air is blown from a cooling air intake through a fan driven by the engine. There is a forced air-cooled type that is guided into the shroud.

FIG. 16 is a side view showing a general example of a forced air-cooled swing type power unit in which an engine is arranged substantially horizontally and a cylinder thereof is arranged in parallel with a traveling direction axis of a vehicle. FIG. Horizontal sectional view (A in FIG. 16)
FIG. 2 is a cross-sectional view taken along line -A).

As shown in FIGS. 16 and 17, the swing type power unit 1 is swingably connected to a body frame 2 via a stay 3 so as to be swingable.

An engine 4 is arranged at the front of the swing type power unit 1. This engine 4
It is mainly composed of a crankcase 5, a cylinder 6, and a cylinder head 7, and a reciprocating stroke of a piston 9 in the cylinder 6 arranged in parallel with a traveling direction axis 8 of the vehicle rotates a crankshaft 11 via a connecting rod 10. Exercise. Crankshaft 11
Are disposed in the crankcase 5 in the vehicle width direction (the direction orthogonal to the traveling direction axis 8 of the vehicle), and a pair of bearings 12
Supported by Further, for example, a conduction case 13 is provided on the left side of the engine 4.

A drive pulley 15 of a V-belt transmission mechanism 14 provided in a transmission case 13 is attached to the left end side of the crankshaft 11. The drive pulley 15 of the V-belt transmission mechanism 14 is driven via a V-belt 16. Pulley 1
7, the driving force of the engine 4 is transmitted.

The driven pulley 17 is transmitted to a rear wheel drive shaft 21 via a centrifugal clutch mechanism 18, a driven shaft 19, and an idle shaft 20 provided at a rear portion of the swing type power unit 1. The driving force of the engine 4 is transmitted to a rear wheel 22 fixed to the drive shaft 21.

On the other hand, an exhaust pipe 23a constituting an engine exhaust system 23 is provided on the lower surface of the cylinder 6 of the engine 4.
A muffler 23b is connected downstream of the exhaust pipe 23a, and a carburetor 24 constituting an engine intake system 24 is provided on the back of the crankcase 5.
a and the air cleaner 24b are connected. The article storage room 2 is located above the engine intake system 24.
5 are arranged.

The engine 4 employs a forced air cooling type cooling system, and a shroud 2 is provided around the engine 4.
The cooling air is introduced into the shroud 26 through a cooling air inlet 28 by a fan 27 provided at the right end of the crankshaft 11.

Reference numeral 29 denotes a spark plug connected to the cylinder head 7.

[0014]

However, when the crankshaft is disposed in the crankcase in the vehicle width direction (the direction orthogonal to the traveling direction axis of the vehicle), the crankshaft cantilever on the drive pulley side of the V-belt transmission mechanism. The length of the portion increases the load on the bearing, which is likely to cause trouble in the bearing portion, and is disadvantageous for the vibration of the V-belt.

If a fan is provided at the right end of the crankshaft, the cooling air intake is inevitably opened toward the outside of the vehicle, and the noise generated when the cooling air is sucked is transmitted to the rider and passers-by. Cheap.

Furthermore, if the cylinder is arranged in parallel with the traveling direction axis of the vehicle, the position of the ignition plug is located at the lower front part of the article storage chamber, and maintenance is difficult.

Similarly, the connecting portion of the exhaust pipe to the cylinder is located on the center line of the vehicle, and it is difficult to attach and detach the exhaust pipe.

Furthermore, when the engine is a two-stroke engine, the flow of the air-fuel mixture to the scavenging port can be made equal to the left and right by arranging the valve opposite to the piston. On the contrary, the front of the rear wheel was approaching, and the valve had to be located elsewhere.

Further, due to the layout of the swing type power unit, the engine intake system can be arranged only between the back of the swing type power unit and the bottom of the article storage room.
Therefore, the capacity of the storage room is limited, and it is difficult to flatten the bottom surface of the storage room.

When the engine is provided with a balancer device, it is desirable that the balancer shaft be disposed in parallel with the crankshaft. However, the rear portion of the crankshaft is close to the front portion of the rear wheel, and there is not enough space. ,
If the balancer device is arranged above the crankshaft, it may interfere with the bottom surface of the storage chamber as described above, and if the balancer device is arranged below the crankshaft, the minimum ground clearance decreases, which is not preferable.

The present invention has been made in view of the above-described circumstances, and has as its object to provide a scooter-type vehicle capable of sufficiently securing the capacity of an article storage room.

Another object of the present invention is to provide a scooter type vehicle which facilitates maintenance.

Still another object of the present invention is to provide a scooter-type vehicle in which noise generated when cooling air is sucked is hardly transmitted to a rider or a pedestrian.

Another object of the present invention is to provide a scooter type vehicle capable of sufficiently securing the minimum ground clearance.

Still another object of the present invention is to provide a scooter type vehicle capable of securing a space for disposing a balancer device.

[0026]

According to a first aspect of the present invention, there is provided a scooter-type vehicle, comprising: an engine; The rear wheel held at the end is integrally provided with a conduction case that transmits the driving force, and it can swing freely via a stay on a pivot shaft installed on the body frame,
In addition to having a swing type power unit elastically supported via a rear shock absorber, an article storage room covered by an openable and closable driving seat is provided on the vehicle body frame, and the entire vehicle body including the article storage room is provided. In a scooter-type vehicle covered with a body cover, the swing-type power unit includes a cylinder head of the engine, an engine intake system and an engine exhaust system arranged on a side of the vehicle traveling direction opposite to the transmission case, and While connecting the intake system to the upper side of the engine and connecting the engine exhaust system to the lower side of the engine, a muffler constituting the engine exhaust system is arranged on the opposite side of the transmission case across the rear wheel. Wherein the engine intake system is disposed in a space between the muffler and the article storage room. A.

According to another aspect of the present invention, a stay for suspending the power unit is provided above the swing type power unit.
The pivot shaft is set to be substantially the same height as the upper part of the engine.

Further, in order to solve the above-mentioned problems,
According to a third aspect of the present invention, the minimum ground clearance of an exhaust pipe constituting the engine exhaust system is set to be substantially the same as the minimum ground clearance of the engine.

Further, in order to solve the above-mentioned problem, the minimum ground clearance of the exhaust pipe constituting the engine exhaust system is substantially the same as the minimum ground clearance of the conduction case. It is set to.

[0030]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a left side view showing a first embodiment of a scooter type vehicle to which the present invention is applied, and FIG.
The right side. Further, FIG. 3 is a cross-sectional view of FIG.
FIG. 4 is a sectional view taken along the line IV-IV of FIG. 1.

As shown in FIGS. 1 to 4, the scooter type vehicle 30 has a body frame 31. The body frame 31 includes a down tube 32 and a pair of left and right rear frames 33 extending rearward and upward from the rear end of the down tube 32. An article storage room 35 capable of storing a helmet 34 and the like is provided above the rear frame 33, and a driving seat 36 is installed above the article storage chamber 35 so as to be openable and closable, and behind the article storage chamber 35. For example, a fuel tank 37 is arranged. As clearly shown in FIGS. 1, 2 and 4, the scooter type vehicle 30 has its entire body including the article storage chamber 35 covered with a synthetic resin body cover 38, and its appearance is adjusted. .

A head pipe 39 is provided at the front end of the down tube 32, and a front fork 41, a handle bar 42 and the like for rotatably supporting the front wheel 40 are provided on the head pipe 39. And this handlebar 42
Thereby, the front wheel 40 is steerably rotatable left and right.

On the other hand, a pair of left and right suspension brackets 43 is provided at the center of the rear frame 33. A pivot shaft 44 is provided between the suspension brackets 43, and a swing type power unit 45 is attached to the pivot shaft 44 by a stay 4.
6 is pivotally connected via a swing.

The swing type power unit 45 (hereinafter simply abbreviated as a power unit) includes an engine 47,
Conductive case 4 extending rearward from one side of this engine 47
8 are provided integrally. The transmission case 48 also serves as a swing arm, and is elastically supported by the rear frame 33 by a rear shock absorber 49. Then, a rear wheel 50 as a driving wheel is held at the rear end of the transmission case 48.

The engine 4 is located at the front of the power unit 45.
7 are arranged. The engine 47 is an air-cooled two-cycle single-cylinder engine, and mainly includes a crankcase 51, a cylinder 52, and a cylinder head 53. The stay 46 for suspending the power unit described above is provided on the upper portion of the outer wall of the crankcase 51, and as clearly shown in FIGS.
Is set to be substantially the same as the upper height of the engine 47.

As clearly shown in FIG.
0 side of the traveling direction axis 54, for example, the crankcase 51
A cylinder 52 is disposed in the direction orthogonal to the traveling direction axis 54 of the vehicle 30 and substantially horizontally. The cylinder head 53 has a combustion chamber 5 matching the cylinder 52.
5 is formed, and a spark plug 56
Are screwed together.

The crankcase 51 can be divided into right and left along the traveling direction axis 54 of the vehicle 30, and a crankshaft 57 is arranged on the mating surface in parallel with the traveling direction axis 54 of the vehicle 30. The crankshaft 57 is configured to be splittable back and forth, is connected at an intermediate portion by a crankpin 58, and is supported by a pair of bearings 59.

A piston 61 is connected to the crank pin 58 via a connecting rod 60. The reciprocating motion of the piston 61 in the cylinder 52 causes the crank shaft 57 to rotate. The crank chamber 62 in which the crankshaft 57 in the crankcase 51 is disposed and the inside of the cylinder 52 are communicated by a scavenging passage 63.

At the front side of the crankcase 51, a magneto device 64 is provided. A flywheel magneto 65 constituting a magneto device 64 is fixed to the tip of the crankshaft 57 so as to rotate integrally therewith, and a cooling fan 66 is rotatably fixed to the front surface thereof.

Cylinder 52 which is a heat radiation part of engine 47
A cooling fin 67 is formed on the cylinder head 53 and the cylinder 52 and the cylinder head 53 are formed.
Is covered by a shroud 68. In the shroud 68, a cooling air inlet 69 is formed in the lower part of the article storage chamber 35 and opens in the traveling direction of the vehicle 30.

An oil pump drive gear 70 is provided at the rear of the crankshaft 57, and is configured to drive an oil pump 72 disposed on the back of the crankcase 51 via the oil pump drive shaft 71.
At the rear end of the crankshaft 57, there is provided a drive bevel gear 73 which is a transmission device for transmitting the driving force of the engine 47 while changing the rotation axis of the crankshaft 57 in a different direction.

On the other hand, an idle shaft chamber 74 is formed between the crank chamber 62 and the front portion of the rear wheel 50. In the idle shaft chamber 74, a crank idle shaft 7 is provided.
5 are arranged in a direction orthogonal to the crankshaft 57,
It is supported by bearings 76.

A driven bevel gear 77, which is a transmission device for transmitting the driving force of the engine 47 while converting the rotation axis of the crankshaft 57 in a different direction, is provided near the intermediate portion of the crank idle shaft 75. Is configured to change the rotation axis direction of the crankshaft 57 by meshing with the drive bevel gear 73.

The idle shaft chamber 74 is provided with an idle shaft cover 7 for supporting a crank idle shaft 75.
Blocked by 8. Both bevel gears 73 and 73 are provided on the joint surface between the idle shaft chamber 74 and the idle shaft cover 78.
A shim 79 for adjusting the engagement of 77 is provided,
The crank chamber 62 and the idle shaft chamber 74 are kept liquid-tight by the O-ring 80 and the like.

As clearly shown in FIG.
The transmission case 48 is disposed on the opposite side of the cylinder 52 with respect to the zero traveling direction axis 54. The conductive case 48 is covered by a case cover 81 and has a belt chamber 82 therein.
The V-belt type automatic transmission 83 is disposed in the belt chamber 82.

The left end of the crank idle shaft 75 projects into the belt chamber 82, and the drive pulley 84 of the transmission 83 is mounted. Drive pulley 84 is V
The driving force of the engine 47 is transmitted to the driven pulley 86 via the belt 85.

The driven pulley 86 is connected to the power unit 4
5, is rotatably supported by a driven shaft 87 provided at the rear of the engine 5, and the rotational driving force from the engine 47 transmitted to the driven pulley 86 is a centrifugal clutch mechanism 88.
Is transmitted to the driven shaft 87 via the

The driven shaft 87 is connected to a rear wheel drive shaft 90 through a transmission mechanism 89 which is a reduction gear mechanism and a power transmission device.
The driving force of the engine 47 is transmitted to the rear wheel 50 through the drive wheels 9.

Incidentally, a portion of the crankcase 51 which is directly opposite to the piston 61, for example, the crankcase 51
A reed valve 92, which is a valve device constituting an engine intake system 91, is provided on the left side of the valve.
The carburetor 9 also constitutes the engine intake system 91 in FIG.
3 is connected via an intake pipe 94. An air cleaner 95, which also forms an engine intake system 91, is connected to the upstream side of the carburetor 93. The air cleaner 95 is arranged in a space formed between the left side surface of the crankcase 51 and the front surface of the conduction case 48 and below the article storage chamber 35.

On the other hand, an exhaust pipe 9 constituting an engine exhaust system 96 is provided on the lower surface of the cylinder 52 of the engine 47.
7 is connected, and a muffler 98 is connected downstream of the exhaust pipe 97. Then, as clearly shown in FIG. 4, the minimum ground clearance of the exhaust pipe 97 is set to be substantially the same as the minimum ground clearance of the engine 47 or the transmission case 48, and the minimum ground clearance of the vehicle 30 is sufficiently ensured.

As described above, the traveling direction axis 5 of the vehicle 30
By arranging the cylinder 52 on one side of the vehicle 4 in a direction orthogonal to the traveling direction axis 54, the connection portion of the ignition plug 56 and the exhaust pipe 97 is located on the side of the vehicle 30, and can be easily detached and maintained. The performance is improved.

Further, the crankshaft 57 is arranged in parallel with the traveling direction axis 54 of the vehicle 30 and a crank idle shaft 75 is provided. By changing the direction, not only the cantilever portion 57a of the crankshaft 57 but also the length of the crank idle shaft 75 is reduced, so that the bearing 5
9, 76 is less likely to be burdened. As a result, the trouble of the bearing portion is reduced, and the vibration of the V-belt 85 is advantageous.

Further, by disposing the cylinder 52 on one side of the traveling direction axis 54 of the vehicle 30 in a direction perpendicular to the traveling direction axis 54, the cylinder 52 and the cylinder head 5
The cooling air intake 69 of the shroud 68 covering the
Can be opened in the direction of travel. As a result, noise generated when the cooling air is sucked is not directly transmitted to the rider or the pedestrian. In addition, since the exhaust air of the cooling air hits the exhaust pipe 97, the cooling efficiency of the exhaust pipe 97 is also improved.

Further, by disposing the cylinder 52 on one side of the traveling direction shaft 54 of the vehicle 30 in a direction perpendicular to the traveling direction axis 54, the cylinder 52 is disposed between the left side surface of the crankcase 51 and the front surface of the transmission case 48. Further, a space is formed below the article storage room 35, and the engine intake system 91 can be arranged in this space. As a result, the reed valve 92 can be disposed directly opposite to the piston 61, so that the flow of the air-fuel mixture to the scavenging passage 63 can be equalized in the left and right directions, and there is sufficient space between the back surface of the power unit 45 and the bottom surface of the article storage chamber 35 A sufficient space can be secured, and the bottom surface of the article storage chamber 35 can be flattened, so that the volume of the article storage chamber 35 can be sufficiently ensured.

Also, by setting the pivot shaft 44 to be substantially the same height as the upper portion of the engine 47, a sufficient space can be secured between the back surface of the power unit 45 and the bottom surface of the article storage chamber 35. The effect of is obtained.

In the above-described embodiment, an example is shown in which the bevel gears 73 and 77 are used as transmission devices for transmitting the driving force of the engine 47 while changing the rotation axis of the crankshaft 57 in different directions. Regardless of the bevel gears 73 and 77, a hypoid gear or the like can be used.

Further, in the above-described embodiment, an example is shown in which the stay 46 for suspending the power unit is provided above the outer wall of the crankcase 51. However, as shown in FIGS. And the power unit 45 may be pivotally attached to the rear end of the down tube 32.

Further, in the above-described embodiment, an example is shown in which the air cleaner 95 is disposed in a space formed between the left side surface of the crankcase 51 and the front surface of the transmission case 48 and below the article storage chamber 35. As shown in FIG. 6, the air cleaner 95 may be disposed on the case cover 81 of the conduction case 48.

FIG. 7 is a left side view showing a second embodiment of a scooter type vehicle to which the present invention is applied, and FIG.
The right side. 9 is a cross-sectional view taken along line IX-IX of FIG. 7, and FIG. 10 is a cross-sectional view taken along line XX of FIG. Note that the scooter type vehicle 1 of the second embodiment is
Since 00 is basically the same as the scooter type vehicle 30 shown in the first embodiment, the same components are denoted by the same reference numerals.

As shown in FIGS. 7 to 10, the scooter type vehicle 100 has a body frame 31. The body frame 31 includes a down tube 32 and a pair of left and right rear frames 33 extending rearward and upward from the rear end of the down tube 32. Also, the rear frame 33
The article storage room 3 which can store the helmet 34 etc.
A driving seat 36 is provided above the article storage room 35.
Is installed so as to be openable and closable, and, for example, a fuel tank 37 is disposed behind the article storage chamber 35. As clearly shown in FIGS. 7, 8 and 10, the scooter type vehicle 100 has its entire body including the article storage chamber 35 covered with a synthetic resin body cover 38, and its appearance is adjusted. .

A head pipe 39 is provided at the front end of the down tube 32, and a front fork 41 and a handle bar 42 for rotatably supporting the front wheel 40 are provided on the head pipe 39. And this handlebar 42
Thereby, the front wheel 40 is steerably rotatable left and right.

On the other hand, a pair of left and right suspension brackets 43 is provided at the center of the rear frame 33. A pivot shaft 44 is provided between the suspension brackets 43, and a swing type power unit 101 is swingably connected to the pivot shaft 44 via a stay 46.

The swing type power unit 101 (hereinafter simply referred to as a power unit) is an engine 102.
And a transmission case 48 extending rearward from one side of the engine 102. The transmission case 48 also serves as a swing arm, and is provided with the rear shock absorber 4.
9 supports the rear frame 33 elastically. Then, a rear wheel 50 as a driving wheel is held at the rear end of the transmission case 48.

An engine 102 is arranged in front of the power unit 101. The engine 102 is an air-cooled 4-cycle single-cylinder engine, and mainly includes a crankcase 10.
3, a cylinder 104, a cylinder head 105 and a head cover 106. The stay 46 for suspending the power unit is connected to the crankcase 103.
Provided at the top of the outer wall, and as clearly shown in FIGS.
2 is set to be substantially the same height as the upper height.

As clearly shown in FIG. 9, on one side of the vehicle traveling direction shaft 54, for example, on the right side of the crankcase 103, the cylinder 104 is
Are arranged in a direction orthogonal to and substantially horizontally. A combustion chamber 55 is formed in the cylinder head 105 so as to be aligned with the cylinder 104, and a spark plug 56 is screwed from the outside. Further, a valve operating mechanism 108 including an intake / exhaust valve (not shown) and a camshaft 107 for opening and closing these valves is disposed above the cylinder head 105. The valve operating mechanism 108 is covered by a head cover 106.

The crankcase 103 can be divided into right and left along the traveling direction axis 54 of the vehicle 100, and the crankshaft 57 is
And are arranged in parallel. The crankshaft 57 is configured to be splittable back and forth, is connected at an intermediate portion by a crankpin 58, and is supported by a pair of bearings 59.

A piston 61 is connected to the crank pin 58 via a connecting rod 60. The reciprocating motion of the piston 61 in the cylinder 104 causes the crank shaft 57 to rotate.

A cam chain drive sprocket 109 is provided at the front of the crankshaft 57. Also,
A cam chain driven sprocket 110 is provided at the front of the cam shaft 107, and both sprockets 109,
110 are connected by a cam chain 111. A cam chain chamber 112 is formed at the front side of the cylinder 104 and the cylinder head 105, and the cam chain 111 is housed therein.

A magneto device 64 is provided on the front side of the crankcase 103. A flywheel magneto 65 constituting a magneto device 64 is fixed to the tip of the crankshaft 57 so as to rotate integrally therewith, and a cooling fan 66 is rotatably fixed to the front surface thereof.

Cylinder 1 which is a heat radiation part of engine 102
Cooling fins 67 are formed on the cylinder head 104 and the cylinder head 105, and the cylinder 104 and the cylinder head 105 are covered with a shroud 68. In the shroud 68, a cooling air intake 69 is formed below the article storage chamber 35 and opens in the traveling direction of the vehicle 100.

A starter gear 114 is provided at the rear of the crankshaft 57 via a starter clutch 113, and the crankcase 103 is connected via an idle gear 115.
It is operatively connected to a drive shaft 117 of a starter motor 116 disposed on the back. At the rear end of the crankshaft 57, there is provided a drive bevel gear 73 which is a transmission device for transmitting the driving force of the engine 102 while changing the rotation axis of the crankshaft 57 in a different direction.

On the other hand, an idle shaft chamber 74 is formed between the crank chamber 62 of the crank case 103 in which the crank shaft 57 is housed and the front part of the rear wheel 50. A crank idle shaft 75 is disposed in the idle shaft chamber 74 in a direction orthogonal to the crank shaft 57 and supported by bearings 76.

A driven bevel gear 77, which is a transmission device for transmitting the driving force of the engine 102 while converting the rotation axis of the crankshaft 57 in a different direction, is provided near the intermediate portion of the crank idle shaft 75. Is configured to change the rotation axis direction of the crankshaft 57 by meshing with the drive bevel gear 73.

The idle shaft chamber 74 is provided with an idle shaft cover 7 for supporting the crank idle shaft 75.
Blocked by 8. Both bevel gears 73 and 73 are provided on the joint surface between the idle shaft chamber 74 and the idle shaft cover 78.
A shim 79 for adjusting the engagement of 77 is provided,
The crank chamber 62 and the idle shaft chamber 74 are kept liquid-tight by the O-ring 80 and the like.

As clearly shown in FIG. 9, the vehicle 1
The transmission case 48 is arranged on the opposite side of the cylinder 104 with respect to the traveling direction shaft 54 of 00. Conduction case 48
Is covered by a case cover 81 to form a belt chamber 82 therein, in which a V-belt type automatic transmission 83 is disposed.

The left end of the crank idle shaft 75 projects into the belt chamber 82, and the drive pulley 84 of the transmission 83 is mounted. The drive pulley 84 is connected to a driven pulley 86 via a V-belt 85,
The driving force of the engine 102 is transmitted to the driven pulley 86.

The driven pulley 86 is connected to the power unit 1
The rotational driving force from the engine 102 transmitted to the driven pulley 86 is transmitted to the driven shaft 87 via the centrifugal clutch mechanism 88.

The driven shaft 87 is connected to a rear wheel drive shaft 90 through a transmission mechanism 89 which is a reduction gear mechanism and a power transmission device.
The driving force of the engine 102 is transmitted to the rear wheels 50 via the drive wheels 9.

On the other hand, an exhaust pipe 97 constituting the engine exhaust system 96 is connected to an exhaust passage 118 on the lower surface of the cylinder head 105.
The muffler 98 is connected to the downstream side. As clearly shown in FIG. 10, the minimum ground clearance of the exhaust pipe 97 is set to be substantially the same as the minimum ground clearance of the engine 102 or the transmission case 48, and the minimum ground clearance of the vehicle 100 is sufficiently ensured.

A carburetor 120 constituting an engine intake system 119 is arranged near the cylinder head 105 and on the opposite side of the cam chain chamber 112, and is connected to an intake passage 122 on the upper surface of the cylinder head 105 via an intake pipe 121. You.

Further, an air cleaner 123 similarly constituting the engine intake system 119 is connected to the upstream side of the carburetor 120. This air cleaner 123 is formed at the rear of the cylinder 104 and the cylinder head 105, on the right side of the rear wheel 50, and between the muffler 98 and the article storage chamber 35, as is clearly shown in FIGS. Is placed in the space.

A breather hose 124 is attached to the wall of the idle shaft chamber 74,
The blow-by gas accumulated in the inside is guided to the air cleaner 123. The breather hose 124 may be provided on the upper wall or the side wall of the crankcase 103 near the crankshaft 57.

As described above, by arranging the cylinder 104 on one side of the traveling direction axis 54 of the vehicle 100 in a direction perpendicular to the traveling direction axis 54, the connection portions of the ignition plug 56 and the exhaust pipe 97 are connected to the vehicle 100. It is located on the side and can be easily attached and detached, improving maintainability.

The crankshaft 57 is connected to the vehicle 100
And a crank idle shaft 75 is provided, and both shafts 57, 75 are connected by bevel gears 73, 77 so as to change the rotation axis direction of the crankshaft 57. Not only the cantilever portion 57a of the crankshaft 57 but also the length of the crank idle shaft 75 is shortened, so that the bearings 59 and 76 are less likely to be burdened. As a result, the trouble of the bearing portion is reduced, and the vibration of the V-belt 85 is advantageous.

Further, by arranging the cylinder 104 on one side of the traveling direction axis 54 of the vehicle 100 in a direction perpendicular to the traveling direction axis 54, the cooling air intake 69 of the shroud 68 covering the cylinder 104 and the cylinder head 105 is formed. It is possible to open toward the traveling direction of the vehicle 100. As a result, noise generated when the cooling air is sucked is not directly transmitted to the rider or the pedestrian.

Further, the traveling direction axis 54 of the vehicle 100
The cylinder 104 is arranged on one side in a direction perpendicular to the traveling direction axis 54, and the transmission case 48 is arranged on the opposite side of the cylinder 104 across the traveling direction axis 54, so that the rear part of the cylinder 104 and the cylinder head 105 Thus, a space is formed on the right side of the rear wheel 50 and between the muffler 98 and the article storage chamber 35, and the engine intake system 119 can be arranged in this space. As a result, a sufficient space can be secured between the back surface of the power unit 101 and the bottom of the article storage chamber 35, and the bottom of the article storage chamber 35 can be flattened, and the volume of the article storage chamber 35 can be sufficiently secured.

Then, the pivot shaft 44 is connected to the engine 102.
By setting the height to be substantially the same as the height of the upper part, a sufficient space can be secured between the back surface of the power unit 101 and the bottom surface of the article storage chamber 35, and the same effect can be obtained.

In the above-described embodiment, an example is shown in which the bevel gears 73 and 77 are used as transmission devices for transmitting the driving force of the engine 102 while changing the rotation axis of the crankshaft 57 in different directions. Regardless of the bevel gears 73 and 77, a hypoid gear or the like can be used.

In the above-described embodiment, an example is shown in which the stay 46 for suspending the power unit is provided above the outer wall of the crankcase 103, but FIG.
As shown in (2), the stay 46 may be provided below the outer wall of the crankcase 103, and the power unit 101 may be pivotally attached to the rear end of the down tube 32.

Further, in the above-described embodiment, an example is shown in which the engine intake system 119 is disposed in the space formed at the rear of the cylinder 104 and the cylinder head 105, above the muffler 98, and to the right of the rear wheel 50. As shown in FIG. 11, the engine intake system 119 is connected to the cylinder 1
12, and may be formed between the left side surface of the crankcase 103 and the front surface of the transmission case 48 and below the article storage chamber 35 as shown in FIG. Air cleaner 123 in space
May be arranged, and the air cleaner 123 and the carburetor 120 may be connected using the duct 125.

FIG. 13 is a left side view of the power unit 126 showing an example in which the balancer device 127 is provided in the engine 102 used in the second embodiment described above, and FIG. 14 is taken along the line XIV-XIV in FIG. It is sectional drawing.

As shown in FIGS. 13 and 14, the balancer device 127 includes a crankcase 1 on the front surface of the transmission case 48.
03 on the left side. This balancer device 127 includes:
A balancer shaft 129 arranged parallel to the crankshaft 57 and supported by a pair of bearings 128
A balancer weight 130 fixed to the balancer shaft 129; and a balancer driven gear 13 provided at one end of the balancer shaft 129 and meshing with a balancer drive gear 131 provided on the crankshaft 57.
And 2. Also, this balancer device 127
Is an opening 1 formed on the left side of the crankcase 103.
The opening 133 is closed by a balancer cover 134.

As described above, the cylinder 104 is mounted on the vehicle 1
By arranging the balancer shaft 129 in a direction orthogonal to the traveling direction axis 54 of the 00, the balancer shaft 129 can be arranged parallel to the crankshaft 57 at a position that does not interfere with other members.

In the above-described embodiment, an example is shown in which the breather hose 124 is mounted on the wall of the idle shaft chamber 74 or on the upper wall or the side wall of the crankcase 103. However, as shown in FIGS.
The breather hose 124 may be mounted near the position 27, for example, on the balancer cover 134.

In the two-stroke engine 47 shown in the first embodiment, the crankshaft 57
An oil pump drive gear 70 is provided on the rear end side of the oil pump 7 and an oil pump 7
2 has been shown to be driven, for example, in FIG.
As shown in FIG. 5, the right end of the crank idle shaft 75 may be extended to the wall surface, and the oil pump 72 may be directly connected to the extended end 75a.

Further, 4 shown in the second embodiment described above.
In the cycle engine 102, the oil pump 72
The description of the two-stroke engine 47 is omitted.
Similarly, the extension end portion 75a of the crank idle shaft 75
It is also possible to connect an oil pump directly to the motor. In this case, an oil filter (not shown) may be arranged near the oil pump.

[0098]

As described above, according to the scooter type vehicle according to the present invention, the transmission case for transmitting the driving force to the engine and the rear wheel extending rearward from one side of the engine and held at the rear end thereof. A scooter type having a swing type power unit swingably and elastically supported on a body frame, and having an article storage room on the body frame, and covering the entire body with a body cover. In the vehicle, the swing type power unit includes a cylinder head of the engine, an engine intake system and an engine exhaust system disposed on a side opposite to the transmission case on an axis in a traveling direction of the vehicle, and connects the engine intake system to the cylinder head. On the upper side, the engine exhaust system is connected to the lower side of the cylinder head, while the engine intake system is connected to the cylinder head. Since it is located in the space formed on the opposite side of the conduction case with the rear wheel behind the dahead, sufficient space can be secured between the back of the power unit and the bottom of the article storage room, and the bottom of the article storage chamber is flattened. And the volume of the article storage room can be sufficiently secured.

[Brief description of the drawings]

FIG. 1 is a left side view of a scooter-type vehicle showing a first embodiment of a scooter-type vehicle according to the present invention.

FIG. 2 is a right side view of the scooter type vehicle shown in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1;

FIG. 5 is a left side view of the power unit showing another mounting position of the power unit suspension stay.

FIG. 6 is a left side view of the power unit showing another arrangement position of the air cleaner.

FIG. 7 is a left side view of the scooter type vehicle, showing a second embodiment of the scooter type vehicle according to the present invention.

FIG. 8 is a right side view of the scooter type vehicle shown in FIG.

FIG. 9 is a sectional view taken along the line IX-IX of FIG. 7;

FIG. 10 is a sectional view taken along the line XX of FIG. 7;

FIG. 11 is a plan view of the power unit showing another arrangement position of the engine intake system.

FIG. 12 is a plan view of the power unit showing another arrangement position of the engine intake system.

13 is a left side view of a power unit showing an example in which a balancer device is provided in the engine shown in FIG. 9;

FIG. 14 is a sectional view taken along the line XIV-XIV in FIG. 13;

FIG. 15 is a partial plan cross-sectional view of the power unit showing another arrangement position of the oil pump.

FIG. 16 is a side view showing a general example of a forced air-cooled swing type power unit in which an engine is arranged substantially horizontally and a cylinder thereof is arranged in parallel with a traveling direction axis of the vehicle.

FIG. 17 is a sectional view taken along the line AA of FIG. 16;

[Description of Signs] 30, 100 Scooter type vehicle 31 Body frame 32 Down tube 33 Rear frame 35 Article storage room 36 Operation seat 38 Body cover 44 Pivot shaft 45, 101, 126 Swing type power unit 46 Stay 47 Two-cycle engine 48 Conductive case 49 Rear shock absorber 50 Rear wheel 51,103 Crankcase 52,104 Cylinder 53,105 Cylinder head 54 Vehicle traveling direction axis 56 Spark plug 57 Crankshaft 66 Cooling fan 68 Shroud 69 Cooling air inlet 73 Drive bevel gear (conduction device) 75 Crank idle shaft 77 Driven bevel gear (conduction device) 83 V-belt automatic transmission 90 Rear wheel drive shaft 91, 119 Engine intake system 92 Reed valve ( Lube apparatus) 93,120 carburetor 96 an engine exhaust system 97 exhaust pipe 98 muffler 102 4-cycle engine 105 Cylinder head 108 valve operating mechanism 111 cam chain 112 cam chain chamber 127 balancer 129 balancer shaft

Claims (1)

[Claims] An engine and a transmission case extending rearward from one side of the engine and transmitting driving force to a rear wheel held at a rear end thereof are integrally provided, and are swingably and elastically mounted on a body frame. A scooter-type vehicle having a swing-type power unit supported on the vehicle body and having an article storage chamber on the body frame, and covering the entire body with a body cover, wherein the swing-type power unit is the transmission case of the vehicle traveling direction axis. The cylinder head of the engine, the engine intake system, and the engine exhaust system are arranged on the opposite side, and the engine intake system is connected to the upper side of the cylinder head, and the engine exhaust system is connected to the lower side of the cylinder head. On the other hand, the engine intake system is formed on the opposite side of the transmission case with the rear wheel behind the cylinder head. A scooter-type vehicle that is arranged in a space formed.