JP3536804B2 - Scooter type vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scooter-type vehicle, and more particularly to a scooter-type vehicle characterized by an engine layout.

[0002]

2. Description of the Related Art Many scooter type vehicles have a swing type power unit. A swing type power unit (hereinafter simply abbreviated as a power unit) includes an engine,
The transmission case is provided integrally with a transmission case that includes a transmission that extends rearward from one side of the engine, and is provided on a body frame or the like to be swingable.

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

As an example of a cylinder arranged in a direction perpendicular to the traveling direction of a vehicle, see, for example,
In addition to those disclosed in JP-A-81884 and JP-A-63-106194, French Patent 1.133.249
There are the following.

FIG. 19 is a side view showing a general example of a liquid-cooled 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. 20 is a horizontal sectional view of the engine. FIG. 20 is a diagram (a cross-sectional view taken along line AA of FIG. 19).

As shown in FIGS. 19 and 20, the power unit 1 is pivotally connected to a vehicle body frame 2 via a stay 3 so as to be swingable.

An engine 4 is arranged at the front of the power unit 1. The engine 4 mainly includes a crankcase 4a, a cylinder 4b, and a cylinder head 4c.
The reciprocating stroke of the piston 6 in the cylinder 4 b arranged in parallel with the traveling direction axis 5 of the vehicle causes the crankshaft 8 to rotate via the connecting rod 7.

The crankshaft 8 is connected to the crankcase 4.
a in the vehicle width direction (direction orthogonal to the traveling direction axis 5 of the vehicle)
And is supported by a pair of bearings 9. Further, for example, a conduction case 10 is provided on the left side of the engine 4.

A drive pulley 12 a of a V-belt transmission mechanism 11 provided in a transmission case 10 is attached to the left end of the crankshaft 8.
, The driving force of the engine 4 is transmitted to the driven pulley 12b.

Further, a centrifugal clutch mechanism 1 provided at the rear of the power unit 1 extends from the driven pulley 12b.
4, driven shaft 15, and idle shaft 1
The driving force of the engine 4 is transmitted to a rear wheel drive shaft 17 through the rear wheel 6 and to a rear wheel 18 fixed to the rear wheel drive shaft 17.

On the other hand, an exhaust pipe 19 constituting an engine exhaust system 19 is provided on the lower surface of the cylinder 4b of the engine 4.
a, and a muffler 19b is connected downstream of the exhaust pipe 19a.
A carburetor 20a and an air cleaner 20b that constitute the engine intake system 20 are connected to the back of a. An article storage room 21 is arranged above the engine intake system 20.

The engine 4 employs a liquid cooling type cooling system, and includes a cylinder 4 b and a cylinder head 4.
A water jacket 22 for the engine cooling water is formed in c. On the other hand, for example, a water pump 24 driven by the crankshaft 8 via a plurality of gears 23 is disposed in the transmission case 10. Further, a radiator 25 for cooling water is arranged near the article storage room 21. The water jacket 22, the water pump 24, and the radiator 25 are respectively connected by cooling water hoses 26, and the cooling water cooled by the radiator 25 is forcibly fed into the water jacket 22 by the water pump 24, and the cylinder 4 b After being cooled, the cylinder head 4c is guided to the radiator 25. Further, a cooling air inlet 27 is formed on the front surface of the radiator 25 so that traveling wind is guided to the radiator 25.

An ignition plug 28 is connected to the cylinder head 4c.

[0014]

However, when the crankshaft is arranged in the vehicle width direction (the direction orthogonal to the advancing direction axis of the vehicle) in the crankcase, the crankshaft cantilevered portion 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 trouble in the bearing portion, and is disadvantageous for the vibration of the V-belt.

If the cylinder is arranged parallel to 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, making maintenance difficult. Similarly,
The connection of the exhaust pipe to the cylinder is located on the center line of the vehicle, making it difficult to attach and detach.

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

Further, due to the layout of the power unit, the engine intake system can be arranged only between the rear surface of the power unit and the bottom of the article storage chamber. Therefore, the capacity of the storage chamber is limited and the bottom of the storage chamber is flat. Is difficult.

When the engine is provided with a self-starter device, the output shaft of the starter motor is desirably arranged in parallel with the crankshaft. If there is no space and the starter motor is arranged laterally above the crankshaft, there is a risk of interfering with the bottom of the storage chamber as described above, and if the starter motor is arranged below the crankshaft, the minimum ground clearance decreases, which is not preferable. .

When the engine is of a liquid cooling type, if the water pump is disposed in the transmission case, the assemblability is poor. It is difficult to assemble the pump, and it has to be disposed on the side of the power unit, which undesirably increases the width of the power unit. Further, since the driving force is connected to the crankshaft via a plurality of gears, the transmission of the driving force may become unstable.

Further, when the cooling air intake is formed in the front of the radiator, the running wind may be blocked by a part of the rider's body, or rainwater or the like may enter and directly hit the radiator. .

The present invention has been made in view of the above-mentioned 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 that facilitates maintenance.

Still 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.

Another object of the present invention is to provide a scooter type vehicle capable of securing a space for disposing a starter motor.

Still another object of the present invention is to provide a scooter type vehicle in which a water pump can be installed without increasing the width of a power unit.

Another object of the present invention is to provide a scooter type vehicle in which traveling wind guided to a radiator is not blocked and rainwater or the like does not splash on the radiator.

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

[0028]

According to a first aspect of the present invention, there is provided a scooter-type vehicle, comprising: an engine; Swing type power unit that integrates a drive case that transmits driving force to the rear wheel held at the end
On the other hand, in a scooter type vehicle in which an article storage chamber is provided on a body frame and the entire body is covered with a body cover, the engine is provided with a valve mechanism in a cylinder head.
Liquid-cooled four-stroke engine
-The unit is the down tube
The rear end of the valve or the rear frame.
And the cylinder of the engine,
The cylinder head and the swing type power unit
Located on the opposite side of the vehicle's direction of travel from the conduction case
The engine intake system is arranged below the article storage chamber.
On the other hand, a muffler constituting an engine exhaust system is arranged on the opposite side of the transmission case with the rear wheel interposed therebetween, and a radiator constituting the engine cooling system is arranged in the vehicle body cover.

[0029] In order to solve the above-mentioned problem, the radiator is installed in the article storage.
In addition to being disposed around the delivery room , an intake guide duct is disposed in front of the radiator, and an intake port of the intake guide duct is opened toward the front of the vehicle.

Further, in order to solve the above-mentioned problems,
According to a third aspect of the present invention, in the swing type power unit , a camshaft drive mechanism for opening and closing a valve, which constitutes the valve mechanism, is disposed on the opposite side of the engine intake system with respect to a center axis of the cylinder. It is.

[0031] Furthermore, in order to solve the above problems, as described in claim 4, the central axis of the cylinder at least one of the water pump constituting the O Iruponpu or the engine cooling system of the swinging power unit Are arranged on the engine intake system side with the.

In order to solve the above-mentioned problem, a crankcase constituting an engine of the swing type power unit is formed so as to be able to be divided into right and left along an advancing direction axis of the vehicle. And a crankshaft arranged on the mating surface.

Further, in order to solve the above-mentioned problems,
As described in claim 6, the engine of the swing type power unit includes a balancer device, and the balancer device is arranged in parallel with a crankshaft arranged in the engine.

Further, in order to solve the above-mentioned problem, the swing type power unit has a starter motor arranged along the longitudinal direction of the crankshaft.

And, in order to solve the above-mentioned problem,
As described in claim 8, the swing type power unit has a magnet side end portion of the crankshaft or
A water pump constituting the engine cooling system is connected to one of the ends of the crank idle shaft .

[0036]

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. The scooter-type vehicle 30 has its entire body covered with a synthetic resin-made vehicle body cover 38 so that 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
As a result, the front wheel 40 is steerably turned 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 mounted on the pivot shaft 44.
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,
A conductive case 4 extending rearward from one side of the engine 47
8 are integrally provided. 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 provided at the front of the power unit 45.
7 are arranged. The engine 47 is a liquid (water) -cooled two-cycle single-cylinder engine, and mainly has a crankcase 5.
1, a cylinder 52 and a cylinder head 53. The stay 4 for suspending the power unit described above is used.
6 is provided on the upper part of the outer wall of the crankcase 51.

On one side, for example, the right side of the crankcase 51, a cylinder 52 is disposed in a direction perpendicular to the traveling direction axis 54 of the vehicle 30 and substantially horizontally. Further, a combustion chamber 55 is formed in the cylinder head 53 so as to match the cylinder 52, and a spark plug 56 is screwed to the center of the cylinder head 53 from outside. A water jacket 57 for engine cooling water is formed around the combustion chamber 55 of the cylinder 52 and the cylinder head 53.

The crankcase 51 can be divided into left and right along a traveling direction axis 54 of the vehicle 30, and a crankshaft 58 is disposed parallel to the traveling direction axis 54 of the vehicle 30 on the mating surface. The crankshaft 58 is configured to be splittable back and forth, is connected at an intermediate portion by a crankpin 59, and is supported by a pair of bearings 60.

A piston 62 is connected to the crank pin 59 via a connecting rod 61, and the reciprocating motion of the piston 62 in the cylinder 52 causes the crank shaft 58 to rotate. The crank chamber 63 in which the crankshaft 58 in the crankcase 51 is disposed and the inside of the cylinder 52 are communicated by a scavenging passage 64.

At the front side of the crankcase 51, a magneto device 65 is provided. The front surface of the magneto device 65 is covered with a magneto cover 66, and a water pump 67 is disposed substantially at the center. This water pump 67
Is connected to the front end of the crankshaft 58 and is configured to be driven by the rotational force of the crankshaft 58.

On the other hand, as shown in FIG. 3, an oil pump drive gear 68 is provided at the rear of the crankshaft 58 with the center axis (not shown) of the cylinder 52 interposed therebetween. It is configured to drive an oil pump 70 disposed on the back of the case 51. At the rear end of the crankshaft 58, there is provided a drive bevel gear 71 which is a transmission device for transmitting the driving force of the engine 47 while changing the rotation axis of the crankshaft 58 in different directions.

On the other hand, an idle shaft chamber 72 is formed between the crank chamber 63 and the front portion of the rear wheel 50. In the idle shaft chamber 72, a crank idle shaft 7 is provided.
3 are arranged in a direction orthogonal to the crankshaft 58,
It is supported by the bearing 74.

A driven bevel gear 75, which is a transmission device for transmitting the driving force of the engine 47 while converting the rotation axis of the crankshaft 58 in a different direction, is provided near the intermediate portion of the crank idle shaft 73. Is configured to change the direction of the rotation axis of the crankshaft 58 by meshing with the drive bevel gear 71.

The idle shaft chamber 72 is provided with an idle shaft cover 7 for supporting the crank idle shaft 73.
Blocked by 6. The two bevel gears 71, on the joint surface between the idle shaft chamber 72 and the idle shaft cover 76,
A shim 77 for adjusting the meshing of the gears 75 is provided,
The crank chamber 63 and the idle shaft chamber 72 are kept liquid-tight by the O-ring 78 and the like.

The transmission case 48 is covered with a case cover 79 to form a belt chamber 80 therein, in which a V-belt type automatic transmission 81 is disposed. The left end side of the crank idle shaft 73 protrudes into the belt chamber 80, and a drive pulley 82 of a transmission 81 is mounted. The drive pulley 82 is connected to a driven pulley 84 via a V-belt 83, and the driving force of the engine 47 is transmitted to the driven pulley 84.

The driven pulley 84 is connected to the power unit 4
5 is rotatably supported by a driven shaft 85 provided at the rear of the engine 5, and the rotational driving force from the engine 47 transmitted to the driven pulley 84 is applied to the centrifugal clutch mechanism 86.
Is transmitted to the driven shaft 85 via the

The driven shaft 85 is connected to a rear wheel drive shaft 88 through a transmission mechanism 87 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 via the switch 7.

By the way, a portion of the crankcase 51 opposite to the piston 62, for example, the crankcase 51
A reed valve 90 constituting an engine intake system 89 is provided on the left side of the vehicle. A carburetor 91 also constituting the engine intake system 89 is connected to the reed valve 90 via an intake pipe 92. An air cleaner 93, which also forms an engine intake system 89, is connected to the upstream side of the carburetor 91. This air cleaner 93
Is disposed in a space formed between the left side surface of the crankcase 51 and the front surface of the conductive case 48 and below the article storage chamber 35.

On the other hand, an exhaust pipe 9 constituting an engine exhaust system 94 is provided on the lower surface of the cylinder 52 of the engine 47.
5 is connected, and a muffler 96 is connected downstream of the exhaust pipe 95.

A radiator 97 constituting an engine cooling system is provided on one side of the article storage chamber 35, for example, on the right side of the article storage chamber 35 opposite to the transmission case 48 with respect to the traveling direction axis 54 of the vehicle. This radiator 97 is fixed to the rear frame 33 via a bracket 98, for example. Furthermore, the body cover 38 on the front of the radiator 97
Is formed with a cooling air intake 99, and the traveling wind is guided to the radiator 97 along the side wall of the article storage chamber 35.

Then, the water jacket 57,
The water pump 67 and the radiator 97 are respectively connected by a cooling water hose 100, and the cooling water cooled by the radiator 97 is forcibly fed into the water jacket 57 by the water pump 67, and the cylinder 52
And after cooling the cylinder head 53, the radiator 9
7.

As described above, the cylinder 52 is connected to the vehicle 30
Is arranged in a direction perpendicular to the traveling direction axis 54, the connection portion of the ignition plug 56 and the exhaust pipe 95 is located on the side of the vehicle 30, and can be easily attached and detached, thereby improving the maintainability.

The crankshaft 58 is arranged in parallel with the traveling direction axis 54 of the vehicle 30, and a crank idle shaft 73 is provided. The two shafts 58, 73 are connected by bevel gears 71, 75 to rotate the crankshaft 58. By changing the direction, not only the cantilever portion 58a of the crankshaft 58 but also the length of the crank idle shaft 73 is reduced, and the bearing 6
0,74 is less likely to be burdened. As a result, the trouble of the bearing portion is reduced, and the vibration of the V-belt 83 is advantageous.

Further, by disposing the camshaft drive mechanism for opening and closing the valve on the opposite side of the engine intake system with respect to the center axis of the cylinder, the space around the cylinder can be effectively used. The assemblability and maintainability are 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 disposed 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 89 can be arranged in this space.
As a result, the reed valve 90 can be disposed directly opposite to the piston 62, so that the flow of the air-fuel mixture to the scavenging passage 64 can be made equal between the left and right sides, and there is sufficient space between the back surface of the power unit 45 and the bottom surface of the article storage chamber 35. 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.

A magneto device 65 is provided on the front side of the crankcase 51, and a water pump 67 is disposed on a magneto cover 66 covering the front of the magneto device 65.
By configuring the water pump 67 so as to be connected to the front end of the crankshaft 58 and driven, the water pump 67 is easily assembled and the width of the power unit 45 is not increased. Further, since the water pump 67 is directly connected to the crankshaft 58, the transmission of the driving force is stabilized.

In the above-described embodiment, an example is shown in which the bevel gears 71 and 75 are used as transmission devices for transmitting the driving force of the engine 47 while changing the rotation axis of the crankshaft 58 in different directions. Regardless of the bevel gears 71 and 75, 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 on the upper portion of 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 93 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 93 may be disposed on the case cover 79 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. It should be noted that the scooter type vehicle 1 of the second embodiment example
01 is basically the same as the scooter type vehicle 30 shown in the first embodiment, so the same components are denoted by the same reference numerals.

As shown in FIGS. 7 to 10, the scooter type vehicle 101 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. The scooter-type vehicle 101 has its entire body covered with a body cover 38 made of synthetic resin, 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
As a result, the front wheel 40 is steerably turned 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 102 is swingably connected to the pivot shaft 44 via a stay 46.

The swing type power unit 102 (hereinafter simply abbreviated as a power unit) has an engine 103.
And a transmission case 48 extending rearward from one side of the engine 103. 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 103 is arranged in front of the power unit 102. This engine 103 is a liquid (water)
The engine is a cold four-cycle single-cylinder engine, and mainly includes a crankcase 104, a cylinder 105, a cylinder head 106, and a head cover 107. The stay 46 for suspending the power unit is connected to the crankcase 1.
04 Provided above the outer wall.

On one side, for example, the right side of the crankcase 104, a cylinder 105 is disposed in a direction perpendicular to the traveling direction axis 54 of the vehicle 101 and substantially horizontally. Further, a combustion chamber 55 matching the cylinder 105 is formed in the cylinder head 106, and a spark plug 56 is screwed from the outside. Then, the cylinder 105 and the cylinder head 1
A water jacket 57 for engine cooling water is formed around the combustion chamber 55 at 06. Furthermore, cylinder head 1
A valve mechanism 109 including an intake / exhaust valve (not shown) and a camshaft 108 for opening and closing these valves is disposed in an upper part of the valve 06. The valve mechanism 109 is covered by a head cover 107.

The crankcase 104 can be divided into left and right along the traveling direction axis 54 of the vehicle 101.
And are arranged in parallel. The crankshaft 58 is configured to be splittable back and forth, is connected at an intermediate portion by a crankpin 59, and is supported by a pair of bearings 60.

A piston 62 is connected to the crank pin 59 via a connecting rod 61, and the reciprocating motion of the piston 62 in the cylinder 105 causes the crank shaft 58 to rotate.

As shown in FIG. 9, the crankshaft 58
A cam chain drive sprocket 110 constituting a camshaft drive mechanism is provided on the opposite side of the engine intake system 119 with respect to the center axis (not shown) of the cylinder 105, that is, at the front of the crankshaft 58. A cam chain driven sprocket 1 constituting another camshaft driving mechanism is provided at a front portion of the camshaft 108.
11 are provided. And both sprockets 110, 1
11 is connected by a cam chain 112 constituting another camshaft driving mechanism.

A magneto device 65 is provided on the front side of the crankcase 104 and is covered by a magneto cover 66. A starter driven gear 114 is provided at the rear of the crankshaft 58 via a starter clutch 113, and the crankcase 1
04 is operatively connected to a drive shaft 117 of a starter motor 116 disposed on the back of the vehicle 101 in parallel with the traveling direction axis 54 of the vehicle 101, that is, along the longitudinal direction of the crankshaft 58. Further, at the rear end of the crankshaft 58, a drive bevel gear 71, which is a transmission device that transmits the driving force of the engine 103 while converting the rotation axis of the crankshaft 58 into a different direction, is provided.

On the other hand, an idle shaft chamber 72 is formed between the crankcase 63 of the crankcase 104 in which the crankshaft 58 is housed and the front part of the rear wheel 50. In the idle shaft chamber 72, a crank idle shaft 73 is disposed in a direction orthogonal to the crank shaft 58, and is supported by bearings 74.

A driven bevel gear 75, which is a transmission device for transmitting the driving force of the engine 103 while converting the rotation axis of the crankshaft 58 in a different direction, is provided near the intermediate portion of the crank idle shaft 73. Is configured to change the direction of the rotation axis of the crankshaft 58 by meshing with the drive bevel gear 71.

The idle shaft chamber 72 is provided with an idle shaft cover 7 for supporting the crank idle shaft 73.
Blocked by 6. The two bevel gears 71, on the joint surface between the idle shaft chamber 72 and the idle shaft cover 76,
A shim 77 for adjusting the meshing of the gears 75 is provided,
The crank chamber 63 and the idle shaft chamber 72 are kept liquid-tight by the O-ring 78 and the like.

The transmission case 48 is covered by a case cover 79 to form a belt chamber 80 therein, in which a V-belt type automatic transmission 81 is disposed. The left end of the crank idle shaft 73 projects into the belt chamber 80, and the drive pulley 8 of the transmission 81
2 is attached. Drive pulley 82 is V belt 8
3 and is connected to the driven pulley 84 via the engine 1
03 is transmitted to the driven pulley 84.

The driven pulley 84 is connected to the power unit 1
The rotational drive force from the engine 103 transmitted to the driven pulley 84 is transmitted to the driven shaft 85 via the centrifugal clutch mechanism 86.

The driven shaft 85 is connected to a rear wheel drive shaft 88 through a transmission mechanism 87 which is a reduction gear mechanism and a power transmission device.
The driving force of the engine 103 is transmitted to the rear wheel 50 via the switch 7.

On the other hand, a water pump 118 is arranged on the wall of the crankcase 104 on the right end 73a side of the crank idle shaft 73. The water pump 118 is connected to the right end 73 a of the crank idle shaft 73 and is configured to be driven by the rotational force of the crank idle shaft 73.

An exhaust pipe 95 constituting the engine exhaust system 94 is connected to the lower surface of the cylinder head 106, and a muffler 96 is provided downstream of the exhaust pipe 95.
Is connected. Further, a carburetor 120 constituting an engine intake system 119 is arranged near the cylinder head 106, and is connected to an upper surface of the cylinder head 106 via an intake pipe 121.

An air cleaner 122, which also forms an engine intake system 119, is connected to the upstream side of the carburetor 120. The air cleaner 122 is disposed at a rear portion of the cylinder 105 and the cylinder head 106, above the muffler 96, and in a space formed on the right side of the rear wheel 50.

A breather hose 123 is attached to the wall of the idle shaft chamber 72,
The blow-by gas accumulated inside is configured to be guided to the air cleaner 122. The breather hose 123 may be provided on the upper wall or the side wall of the crankcase 104 near the crankshaft 58.

A radiator 124 constituting an engine cooling system is provided at one side of the article storage chamber 35, for example, on the right front side of the article storage chamber 35 opposite to the transmission case 48 with respect to the traveling direction axis 54 of the vehicle. The radiator 124 is provided with a bracket 125 on the wall of the article storage room 35, for example.
Fixed through. Further, a cooling air intake 99 is formed in the vehicle body cover 38 on the front of the radiator 124 so that traveling wind is guided to the radiator 124 and the radiator 1
The exhaust air passing through 24 is guided backward along the side wall of the article storage chamber 35.

Then, the water jacket 57,
The water pump 118 and the radiator 124 are connected by a cooling water hose 100, respectively.
The cooling water cooled at 24 is forcibly fed into the water jacket 57 by the water pump 118, cools the cylinder 105 and the cylinder head 106, and is then guided to the radiator 124.

As described above, the cylinder 105 is mounted on the vehicle 1
By arranging the connecting portion of the ignition plug 56 and the exhaust pipe 95 on the side of the vehicle 101 by disposing the connecting portion in the direction orthogonal to the traveling direction axis 54 of the vehicle 01, the connecting portion can be easily attached and detached, thereby improving the maintainability.

The crankshaft 58 is connected to the vehicle 101
And a crank idle shaft 73 is provided, and both shafts 58, 73 are connected by bevel gears 71, 75 so as to change the rotation axis direction of the crankshaft 58. Not only the cantilever portion 58a of the crankshaft 58 but also the length of the crank idle shaft 73 is reduced, so that the bearings 60 and 74 are less likely to be burdened. As a result, the trouble of the bearing portion is reduced, and the vibration of the V-belt 83 is advantageous.

Further, the cylinder 105 is connected to the vehicle 101
A space is formed at the rear of the cylinder 105 and the cylinder head 106, above the muffler 96, and to the right of the rear wheel 50 by disposing the engine intake system 119 in this space. It can be placed. As a result, a sufficient space can be secured between the back surface of the power unit 102 and the bottom of the article storage chamber 35, and the bottom of the article storage chamber 35 can be flattened, so that the volume of the article storage chamber 35 can be sufficiently secured.

Then, a water pump 118 is arranged on the wall of the crankcase 104 on the right end 73a side of the crank idle shaft 73, and the water pump 118 is connected to the right end 73a of the crank idle shaft 73 to be driven. As a result, the water pump 11
8 becomes easy and the power unit 102
Without increasing the width. Water pump 1
Since 18 is directly connected to the crank idle shaft 73, the transmission of the driving force is stabilized.

Further, the cylinder 105 is connected to the vehicle 101.
By disposing the starter motor 1 in a direction perpendicular to the traveling direction axis 54 of the
16 can be arranged.

In the above-described embodiment, the example in which the bevel gears 71 and 75 are used as the transmission device for transmitting the driving force of the engine 103 while changing the rotation axis of the crankshaft 58 to a different direction has been described. Regardless of the bevel gears 71 and 75, a hypoid gear or the like can be used.

In the above-described embodiment, the example in which the stay 46 for suspending the power unit is provided on the upper portion of the outer wall of the crankcase 104 is shown.
As shown in FIG. 7, the stay 46 may be provided at a lower portion of the outer wall of the crankcase 104, and the power unit 102 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 on the rear side of the cylinder 105 and the cylinder head 106, above the muffler 96, and on the right side of the rear wheel 50. However, as shown in FIG.
13 and a space formed between the left side surface of the crankcase 104 and the front surface of the transmission case 48 and below the article storage chamber 35 as shown in FIG. Air cleaner 122
Are arranged, and the air cleaner 122 is
And the carburetor 120 may be connected.

In the above-described embodiment, the water pump 118 is arranged on the wall of the crankcase 104 on the right end portion 73a side of the crank idle shaft 73 so as to be driven by the torque of the crank idle shaft 73. Although shown, an oil pump (not shown) may be arranged in addition to the water pump 118.

FIG. 14 is a left side view of a power unit 131 showing an example in which a balancer device 130 is provided in the engine 103 used in the second embodiment described above, and FIG. 15 is taken along the line XV-XV in FIG. It is sectional drawing.

As shown in FIGS. 14 and 15, the balancer device 130 includes a crankcase 1 on the front surface of the transmission case 48.
04 on the left side. This balancer device 130
A balancer shaft 133 arranged parallel to the crankshaft 58 and supported by a pair of bearings 132
A balancer weight 134 fixed to the balancer shaft 133; and a balancer driven gear 13 provided at one end of the balancer shaft 133 and meshing with a balancer drive gear 135 provided at the crankshaft 58.
And 6. Also, the balancer device 130
Is an opening 1 formed in the left side surface of the crankcase 104.
The opening 137 is closed by a balancer cover 138.

As described above, the cylinder 105 is connected to the vehicle 1
By arranging the balancer shaft 133 in a direction perpendicular to the traveling direction axis 54, the balancer shaft 133 can be arranged parallel to the crankshaft 58 at a position that does not interfere with other members.

In the above embodiment, the breather hose 123 is mounted on the wall of the idle shaft chamber 72 or the upper wall or the side wall of the crankcase 104. However, as shown in FIG. 14 and FIG.
The breather hose 123 may be attached to the vicinity of 30, for example, to the balancer cover 138.

In the two-stroke engine 47 shown in the first embodiment, the crankshaft 58
An oil pump drive gear 68 is provided at the rear of the oil pump 70, and an oil pump 70
, And a water pump 67 is disposed on a magnet cover 66 that covers the front surface of the magneto device 65.
8 is configured to be connected to the front end of the crank idle shaft 73 to drive the water pump 67 or the oil pump 70 on the right end 73a of the crank idle shaft 73, as in the engine 103 according to the second embodiment. The oil pump 70 may be provided on the magneto cover 66 and driven by the crankshaft 58.

Further, 4 shown in the second embodiment described above.
In the cycle engine 103, an example is shown in which a water pump 118 is connected to the right end 73a of the crank idle shaft 73, and the description of the oil pump 70 is omitted, but the front surface of the magneto device 65 is covered similarly to the two-cycle engine 47. A water pump 118 may be arranged on the magneto cover 66 and the water pump 118 may be connected to and driven by the front end of the crankshaft 58. Also, the right end 73 a of the crank idle shaft 73 and the front end of the crankshaft 58 may be driven. An oil pump (not shown) may be directly connected to the section.

FIG. 16 is a right side view of a scooter-type vehicle in which a guide duct is provided in a vehicle body, and FIG. 17 is a plan view of the scooter-type vehicle. As shown in FIGS. 16 and 17, this scooter type vehicle 140 has a radiator 14
1 and an exhaust guide duct 143 behind the radiator 141. The intake port 144 of the intake guide duct 142 is open toward the front of the vehicle 140 at a location not obstructed by the rider's body.
144 (a) position), the bay entrance 1 in front of the driving seat 36.
It is conceivable that the front of the indentation 46 (position 144 (b) in FIG. 16) or the rear of the indentation 146 (position 144 (c) in FIG. 16). Since both the intake ports 144 (b) and 144 (c) are opened below the radiator 141, it is possible to prevent rainwater or the like from entering the radiator 141. The intake port 144 (a) is open above the radiator 141, but since the middle of the intake guide duct 142 is located below the radiator 141, entry of rainwater or the like into the radiator 141 can be prevented.

Further, as shown in FIG. 18, an intake guide duct 147 having a plurality of intake ports 144 (d) to 144 (f) may be provided. Further, as shown in FIG. 16, an intake fan 148 may be provided behind the radiator 141 to forcibly take in outside air when the vehicle is stopped or when traveling wind is small.

The guide duct 1 before and after the radiator 141
By providing the radiators 42 and 143, the heat radiation effect of the radiator 141 is enhanced, and the cooling efficiency of the engines 47 and 103 is improved.

In the scooter-type vehicle 140 shown in FIGS. 16 and 17, a part of the rear side of the article storage chamber 150 is extended rearward to form an extension 150a, and tanks such as the fuel tank 151 are provided. It is attached with. By forming the extension 150a in the article storage chamber 150, long objects that could not be stored in the conventional article storage chamber can be stored.

[0108]

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. And a swing type power unit which is swingably and elastically supported on the vehicle body frame, has an article storage room on the vehicle body frame, and covers the entire vehicle body with a vehicle body cover. In the vehicle, the engine is a liquid-cooled engine, and the swing-type power unit includes a cylinder head of the engine, an engine intake system, an engine exhaust system, and an engine cooling system on a side opposite to the transmission case on a traveling direction axis of the vehicle. When the muffler constituting the engine exhaust system is arranged on the opposite side of the transmission case with the rear wheel in between, Since the radiator constituting the engine cooling system is arranged in the vehicle body cover on the side of the article storage chamber, a sufficient space can be secured between the back of the power unit and the bottom of the article storage chamber, and the flat bottom of the article storage chamber can be secured. Thus, 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 in FIG. 7;

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

FIG. 11 is a plan view of the scooter type vehicle shown in FIG. 7;

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

FIG. 13 is a plan view of the power unit showing another arrangement position of the engine intake system.

FIG. 14 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. 15 is a sectional view taken along the line XV-XV in FIG. 14;

FIG. 16 is a right side view of a scooter type vehicle in which a guide duct is provided in a vehicle body.

17 is a plan view of the scooter type vehicle shown in FIG.

FIG. 18 is a side view showing another example of the shape of the intake guide duct.

FIG. 19 is a side view showing a general example of a liquid-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. 20 is a sectional view taken along the line AA of FIG. 20;

[Explanation of symbols]

30, 101, 140 Scooter type vehicle 31 Body frame 32 down tube 33 Rear frame 35,150 goods storage room 45, 102, 131 Swing type power unit 47 two-stroke engine 48 conduction case 50 rear wheel 51,104 Crankcase 52,105 cylinder 53,106 Cylinder head 54 Vehicle traveling direction axis 56 Spark Plug 57 water jacket 58 crankshaft 67,118 Water pump 71 Drive bevel gear (transmission device) 73 crank idle shaft 75 Driven bevel gear (transmission device) 81 V belt type automatic transmission 88 Rear wheel drive shaft 89,119 Engine intake system 91,120 carburetor 94 Engine exhaust system 96 Muffler 97, 124, 141 radiator 103 4-cycle engine 114 Starter driven gear 116 Starter motor 142 Intake guide duct 143 Exhaust guide duct 144 (a)-(f) Inlet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B62K 11/10 B62J 9/00 B62J 39/00 B62M 7/02

Claims (8)

(57) [Claims] 1. A swing type power unit in which an engine is integrated with a transmission case extending rearward from one side of the engine and transmitting driving force to a rear wheel held at a rear end of the engine.
On the other hand, in a scooter type vehicle in which an article storage chamber is provided on a body frame and the entire body is covered with a body cover, the engine is provided with a valve mechanism in a cylinder head.
Liquid-cooled four-stroke engine
-The unit is the down tube
The rear end of the valve or the rear frame.
And the cylinder of the engine,
The cylinder head and the swing type power unit
Located on the opposite side of the vehicle's direction of travel from the conduction case
The engine intake system is arranged below the article storage chamber.
On the other hand, a muffler constituting an engine exhaust system is arranged on the opposite side of the transmission case with the rear wheel interposed therebetween, and a radiator constituting the engine cooling system is arranged in the vehicle body cover. vehicle. 2. The radiator is provided around the article storage chamber.
The scooter-type vehicle according to claim 1, wherein the scooter-type vehicle is provided with an intake guide duct disposed in front of the radiator, and an intake port of the intake guide duct is opened toward the front of the vehicle. Wherein said swinging power unit, according to claim 1 or 2 camshaft drive mechanism for the valve closing constituting the valve mechanism is arranged on the opposite side of the intake system with respect to the center axis of the cylinder Scooter type vehicle as described. 4. The method of claim 1, 2 or 3 at least one of the water pump disposed in the engine intake system side across the central axis of the cylinder constituting the O Iruponpu or the engine cooling system of the swinging power unit
Scooter type vehicle as described. 5. A crankcase constituting an engine of the swing type power unit, wherein the crankcase is formed so as to be able to be divided into right and left along an advancing direction axis of the vehicle, and a crankshaft is arranged on a mating surface thereof. A scooter-type vehicle according to 1. 6. The scooter-type vehicle according to claim 5, wherein the engine of the swing type power unit includes a balancer device, and the balancer device is disposed in parallel with a crankshaft disposed in the engine. 7. The scooter type vehicle according to claim 5, wherein said swing type power unit has a starter motor arranged along a longitudinal direction of a crankshaft thereof. 8. The swing type power unit according to claim 1, wherein the crankshaft has a magnet side end or a crank eye.
7. A water pump constituting the engine cooling system is connected to one of ends of the dollar shaft.
Or a scooter-type vehicle according to 7.