JP2001048081A - Scooter type motorcycle - Google Patents

Abstract

(57) [Summary] [Problem] To improve steering stability by centralizing the position of the center of gravity,
Provided is a scooter-type motorcycle that can be positioned at the center of the center of gravity vehicle front and rear so that high-speed running stability can be improved, a floor width can be reduced, and a space under a seat can be effectively used. SOLUTION: In a body cover 30, an engine 32 and a V-belt transmission 34 are accommodated under a tunnel portion 30a and a seat 12a, and suspended on a frame 20.
When viewed from the side, at least a part of the cylinder head 32a and the cylinder 32b of the engine 32 is disposed below the foot space 14 and below the rider's seat 12a, a crankshaft 32c, a V-belt transmission 34, a balancer shaft 36, and the like. Are arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a layout of an engine, a V-belt type continuously variable transmission mechanism and a power transmission mechanism in a scooter type motorcycle, and more particularly to a high speed scooter mounted with a large engine.

[0002]

2. Description of the Related Art Generally, a scooter type motorcycle is equipped with a unit swing type engine unit. This engine unit is such that an engine unit and a V-belt transmission also function as an integrated unit and a swing arm, and are used in most scooter-type vehicles. This unit swing type engine unit has an advantage that an inexpensive and compact engine unit can be realized.

[0003]

The unit swing type engine unit, however, has the following disadvantages. As the weight (unsprung weight) of the swing part becomes heavy,
The ride feeling is inferior to the general one that fixes the engine to the vehicle body and drives the rear wheels with a chain or shaft. Since the engine part was placed between the vehicle body and the tire, and they oscillated, it was difficult to increase the tire diameter. It could not be used in high-speed vehicles because the load shared by the front wheels tends to be light. That is, in order to ensure running stability during high-speed running, it is necessary to make the front and rear shared load close to 1: 1. However, in the case of a unit swing type engine unit, weight sharing is on the rear side, so it was impossible.

On the other hand, in a scooter type motorcycle, an engine arrangement structure in which a V-belt type continuously variable transmission mechanism and an engine unit are arranged below a footrest step has been proposed (see Japanese Patent Application Laid-Open No. H10-167156). . However, in this type of motorcycle, since the entire engine section and the main part of the transmission mechanism are arranged between the footrest floors, the floor width becomes too wide, the bank angle is small, and the windage resistance is reduced. As the size of the vehicle increases, the size of the vehicle body increases and the appearance quality deteriorates, and there is a problem in that it is difficult to take a riding posture like a scooter type vehicle with the feet as close as possible.

On the other hand, in the transmission mechanism, the filter for the cooling fan in the V-belt chamber and the air cleaner are separated from each other. It is necessary to separate the air cleaner from the air cleaner, and in many cases other parts are disassembled more often, which requires a lot of maintenance man-hours. Although the air cleaner filter cleaning is not forgotten, if it is located at another location, the cooling fan filter cleaning is likely to be forgotten, resulting in insufficient cooling of the V-belt, which may shorten the life of the belt. If the filter and the cleaner are separately provided, the case cannot be shared, so that the filter capacity tends to be small and the cost is high.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has improved steering stability by centralizing the position of the center of gravity. It is an object of the present invention to provide a scooter-type motorcycle that can improve the size and width of a floor and can effectively use a space under a seat. Another object of the present invention is to provide a scooter-type motorcycle that can reduce the number of man-hours and cost for maintenance of a filter for a V-belt chamber cooling fan and an air cleaner.

[0007]

The present invention has the following arrangement to achieve the above object. The present invention relates to a vehicle having a footing space lower than the upper surface of a seat between a frame head pipe and a seat for a rider, wherein at least a part of a cylinder head and a cylinder are arranged below the footing space in a side view, and Crankshaft under seat, V
A scooter-type motorcycle characterized by arranging a rotating portion such as a belt transmission and a balancer shaft. According to the present invention, in the engine storage tunnel portion which is higher than the footrest floor surface, the width of the tunnel portion for accommodating the cylinder head and the cylinder under the foot space can be made relatively narrow due to the cylinder head and the cylinder. The rider's floor surface can be provided on both sides of the tunnel without making the frame cover too wide. In addition, the rotating parts such as the crankshaft, V-belt transmission, and the balancer shaft, which are wider than the cylinder head and cylinder, and the rotating parts such as the balancer shaft for driving the water pump and oil pump, have a wider width under the seat. Since it is housed in a part that can be formed, it can be housed in a good appearance with no difficulty in modeling. The pillion floor comes on both sides, but it is higher than the rider's floor, so even if it becomes wider, the bank angle will not be affected. Moreover, the windage resistance is small. Also, the widest mag cover and the cover end of the primary drive sprocket can be arranged below the floor surface, so that even the widest can be accommodated without difficulty. Also, since the mass can be concentrated near the car weight center on the floor and under the seat,
Driving stability is improved. In addition, since a heavy object such as an engine V-belt transmission and a balancer shaft is disposed in front of the unit swing type engine unit, it is easy to take a load that is easy to drive even at high speeds.

In the present invention, preferably, the inclination angle of the engine cylinder is set to a substantially horizontal forward rising inclination. In this way, the bottom of the foot space can be lowered, so that the foot can be easily passed. In addition, since the cylinder shaft is substantially horizontal, even when secondary vibration is generated in the direction of the cylinder axis, vibration is hardly generated on the steering wheel, seat, and floor.

In the present invention, preferably, the balancer shaft of the engine is disposed substantially behind the crankshaft corresponding to the rear of the vehicle body on the cylinder shaft. With this configuration, parts requiring oil lubrication can be disposed immediately above the oil pan, so that the oil passage can be shortened, the oil passage resistance can be reduced, and a small oil pump can be used. Further, since the width is lower than the pillion rider floor surface, the width can be increased, and a water pump, an oil pump and the like can be arranged on both sides, so that a transmission device dedicated to the pump is not required. This is because it can be shared with the balancer drive.

[0010] In the present invention, preferably, an oil pump and a water pump are respectively disposed at both ends of the balancer shaft, and they are driven by the balancer shaft. In the present invention, preferably, an axis passing through the axis of the drive pulley shaft and the driven pulley shaft of the V-belt transmission is arranged parallel to the cylinder axis and above the crankshaft. A V-belt transmission that is wider than the cylinder head and cylinder but narrower than the crankshaft can be placed under the seat, which can be wider than the foot space above the floor surface.

In the present invention, preferably, a starter clutch (56) of an engine starting device or a sensor rotor of a drive pulley rotation sensor is provided between the drive pulley on the drive pulley shaft of the V-belt transmission and the primary drive sprocket. Things.
As a result, the engine width can be narrower than that provided on the crankshaft because it is provided in the space between the pulley and the primary drive sprocket.

In the present invention, the starter motor is preferably disposed in a space between the crankshaft, the drive pulley shaft and the cylinder, and the intake pipe. As a result, the space can be effectively used, so that the engine unit can be downsized, and the area around the vehicle body seat can be made compact.

In the present invention, preferably, the actuator motor of the V-belt transmission and the reduction gear train thereof
It is arranged above the belt transmission. Thereby, since the width is narrow, the air cleaner can be arranged on the side surface.

In the present invention, preferably, an air cleaner is provided on the side of the actuator motor and its reduction gear train above the V-belt transmission, and the inlet opening of the air cleaner is provided below the seat covered by the body cover. It is arranged on the rear elevation side of the foot space. By using a cleaner having a large volume but a light weight per volume, it is possible to arrange the cleaner so that the weight per volume is heavy on the lower side and lighter as it goes up, so that the center of gravity can be lowered. In addition, since the inlet can be opened at a position where mud or dust does not enter, the life of the filter is increased and a change in setting can be reduced.

In the present invention, preferably, a cushion unit is disposed substantially upright behind a pivot shaft supporting the front end of the swing arm, and an engine case of an engine unit integrally provided with a V-belt transmission and the cushion unit are provided. The battery is disposed in a space surrounded by the pivot shaft of the swing arm or the suspension shaft of the engine case and the lower surface of the seat. Thereby, the space can be effectively used, and the body can be made compact.

In the present invention, the starting clutch (52) is preferably provided between the universal joint and the final drive bevel gear. This allows
Compared to the method provided between the driven pulley and the secondary drive gear, the width of the engine unit is narrower and the space below the seat can be made compact. Further, the width direction of the swing portion can be made narrower than a general swing type in which a centrifugal clutch is provided near the rear wheel by a unit swing type. If the starter clutch is provided near the pivot shaft, the unsprung weight does not increase so much.

In the present invention, the cleaner for the cooling fan of the V-belt chamber of the V-belt transmission is preferably provided integrally with the air cleaner of the engine. Accordingly, since the maintenance of the air cleaner filter and the filter for the cooling fan is performed at the same place, disassembly of other parts is reduced, and at the same time maintenance can be performed, thereby reducing man-hours.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 8 are explanatory views of a scooter type motorcycle according to an embodiment. FIGS. 1 and 2 are overall side views and plan views of the motorcycle, and FIGS. 3 and 4 illustrate an engine and a V-belt transmission. 5 is an explanatory view of a V-belt transmission, FIG. 6 is an explanatory view of an air cleaner, FIG. 7 is an explanatory view of a cooling fan cleaner,
FIG. 8 is an explanatory view in cross section of an actuator for a V-belt transmission and a gear train thereof.

As shown in FIGS. 1 and 2, the motorcycle includes a frame head pipe 10 and a rider (for a driver).
In this vehicle, a foot space 14 lower than the upper surface of the seat 12 is provided between the seats 12. In this motorcycle, the frame head pipe 10 supports a steering fork 18 for suspension of a front wheel 16 in a rotatable (steerable) manner. Frame 2 continuing to head pipe 10
Reference numeral 0 denotes a down tube 20f which temporarily lowers downward in a vertical pair from the rear side of the upper and lower portions of the head pipe 10 and bends rearward at the lower portion, and a roughly ladder type extending obliquely upward and rearward from the lower portion of the down tube 20f. And the entire main tube 20m has a substantially "L" shape or a substantially bow shape in side view. The upper and lower down tubes 20f extend from the head pipe 10 to the left and right in a width of about the width of the engine 32 and extend rearward.
Leads to. The lower one of the upper and lower main tubes 20m has a roughly rectangular shape in plan view, while the upper one of the main tube 20m has a roughly gourd shape with a central portion 20m1 narrowed down (see FIG. 2). .

The rear portion of the main tube 20m is fixed to a vertical tube 20t which is inclined backward and extends vertically, and a rear tube 20r extends obliquely rearward and upward from the upper portion of the vertical tube 20t. Is provided with a pivot shaft 24 that supports the rear swing arm 22. That is, the case of the rear swing arm 22 is fixed to the pivot shaft 24, and the rear swing arm 22 of the rear wheel 8 suspension swings around the pivot shaft 24. The fuel tank 26 is installed between the pair of left and right down tubes 20f of the frame 20 and the head pipe 10. Also, this fuel tank 2
6 is covered with a fairing 28 integral with the windshield 28a, and is covered with a body cover 30 from the center to the rear of the vehicle.

The seat 12 is provided with the main tube 20m.
A rider's seat 12a is provided above the rear side, and a pillion seat 12b, which is one step higher than the rider's seat 12a, is provided above the rear tube 20r. The body cover 30 in front of the seat 12 covers the main tube 20m and forms a U-shaped tunnel section 30a that opens downward in cross section.
The upper end is the foot space 14, which is one step lower than the seat 12a between the head pipe 10 and the driver's seat 12a.

In the body cover 30, the engine 32, the V-belt transmission 34, and the engine case 38 are accommodated under the tunnel 30a and the seat 12a and are suspended from the frame 20, as shown in FIGS. To
When viewed from the side, at least a part of the cylinder head 32a and the cylinder 32b of the engine 32 is disposed below the foot space 14 and below the rider's seat 12a, a crankshaft 32c, a V-belt transmission 34, a balancer shaft 36, and the like. Are arranged. On the left and right of the lower portion of the body cover 30, foot rest floors 40 are installed so as to sandwich the tunnel portion 30a, as shown by hatching in FIG.

In the engine 32, the cylinder 32b
The inclination angle θ is a substantially horizontal upward inclination.
The piston 32d in the cylinder 32b reciprocates in the front-rear direction of the vehicle body, and this reciprocation is converted into rotational motion of the crankshaft 32c via the connecting rod 32e. The crankshaft 32c is rotatably accommodated in an engine case 38, and a V-belt transmission 34 is integrally mounted on the upper part of the engine case 38 with the crank chamber and the V-belt chamber 34c separated by a partition 38a. (Of course, the V-belt transmission 34 can also be formed separately and mounted on the engine case 38 to be integrated). The lower part of the engine case 38 is an oil pan 38b.

In the engine 32, the balancer shaft 36 is disposed substantially behind the vehicle body on the axis Sp of the cylinder 32b (see FIG. 3). Also, the balancer shaft 36
Oil pump 42 and water pump 44
(In the embodiment, the oil pump 42 is disposed at the right end of the vehicle body and the water pump 44 is disposed at the left end of the vehicle body).
(See FIG. 4).

Here, the V-belt transmission 34 comprises a variable diameter pulley and a dry composite belt (a pair of aramid core wire-containing tension members are inserted from the side into a horizontal H-type high-strength aluminum block molded with heat-resistant resin). ), And is a V-belt transmission type electronically controlled transmission system (CVT) combined with a starting clutch 52 described later (see FIGS. 3 and 5).

The V-belt transmission 34 has a drive pulley shaft 34a and a driven pulley shaft 34b. From the primary drive gear 46 provided on the crankshaft 32c to the primary driven sprocket gear 48 of the transmission 34. The engine driving force is transmitted through the chain 49.

In the V-belt transmission 34, the axis passing through the drive pulley shaft 34a and the driven pulley shaft 34 of the V-belt transmission 34 is parallel to the cylinder axis Sp.
In addition, they are arranged above the crankshaft 32c. Here, the drive pulley 5 is attached to the drive pulley shaft 34a.
The fixed face 50f is integrally molded, and the movable face 50m is disposed so as to be movable in the axial direction. The fixed face 50f of the driven pulley 54 is integrally formed with the driven pulley shaft 34b, and the movable face 50m is disposed so as to be movable in the axial direction. In the V-belt transmission 34,
A starter clutch 56 for transmitting the driving force of the starter motor 62 for starting the engine to the crankshaft at the time of starting on a drive pulley shaft 34a between the drive pulley 50 and the primary drive sprocket gear 48, and a sensor rotor 58a of the drive pulley rotational speed sensor 58. Is provided. The starter clutch 56 is a one-way clutch that transmits only one-way rotation. When the engine 32 starts and the rotation of the crankshaft 32c of the engine 32 becomes faster than the rotation of the starter motor 62, the starter clutch 56 This is a clutch for cutting off the power transmission between the engine 32 and the crankshaft 32c of the engine.

A starter motor 62 is disposed in a space between the crankshaft 32c, the drive pulley shaft 34a, the cylinder 32b, and the intake pipe 60.

The V-belt transmission 34 has an actuator motor 64 for driving the movable face 50m of the drive pulley 50 to change the pulley diameter and its reduction gear trains 66a to 66c above the V-belt transmission 34. (See FIG. 3). An air cleaner 68 is provided on the side of the actuator motor 64 and the reduction gear trains 66a to 66c above the V-belt transmission 34, and an inlet opening 68a is provided under the seat 12 covered with the body cover 30 to provide a foot space. 14 rear elevation 14r
(See FIG. 3).

The movable face 54m of the driven pulley 54 on the driven pulley shaft 34b on the output side of the V-belt transmission 34 is provided with a spring (torque cam spring) 70.
Is pressed toward the fixed face 54f with an appropriate pressing force, and the diameter (winding diameter) of the driven pulley 54 via a V-belt (indicated by reference numeral 71) corresponding to a change in the diameter (winding diameter) of the drive pulley 50. ) Changes.

The pulley 5 is driven on the driven pulley shaft 34b.
4 is provided with a secondary drive gear 72a of a bevel gear, a secondary driven gear 72b and a bevel shaft 72c are arranged in a direction perpendicular to the pulley shaft 34b, and the drive gear 72a and the driven gear 72b engage with each other. The rotation axis direction is changed from the lateral direction of the pulley shaft 34b to the rearward direction of the bevel shaft 72c. The rear end of this bevel shaft 72c
The driving force is transmitted to the rear wheel 8 by being connected to a propeller shaft 76 provided in the rear swing arm 22 by a universal joint 74.

The rear swing arm 22 has a cylindrical case frame 22f. The rear swing arm 22 is eccentrically fixed to the left side in the width direction of a pivot shaft 24, which is rotatably supported on the left and right of a main tube (main frame) 20m. It has a cantilever structure that is pivotally supported from the left side. Also, the rear swing arm 22
The lower end of the cushion unit 78 is fixed to the shaft, and the upper end of the cushion unit 78 is viewed axially at the intersection of the rear end of the main tube 20m and the vertical tube 20t. The pivot axis center and the swing center of the propeller shaft 76 coincide with each other. In the rear end of the rear swing arm 22, a final bevel gear for transmitting the driving force of the propeller shaft 76 to the rear wheel 8 is provided.

In this embodiment, a cushion unit 78 is disposed substantially upright behind the pivot shaft 24 which supports the front end of the rear swing arm 22, and the V-belt transmission 34, the actuator motor 64 and its reduction gear trains 66a-6
The rear end of the engine case 38 of the engine unit integrally provided with 6c and the like and the cushion unit 78 and the pivot shaft 24 of the swing arm 22 or the engine case 38
The battery and the battery case 82 are provided in a space surrounded by the suspension shaft and the lower surface of the seat 12 (see FIG. 3).

The starting clutch 52 is formed of, for example, an electronically controlled electromagnetic clutch.
4 and a final drive bevel gear, and in the embodiment, the propeller shaft 76 is divided in the middle and interposed therebetween. The V-belt chamber 34
c, in order to make the diameter of the drive pulley 50 variable,
Actuator motor 64 and reduction gear trains 66a to 66c
Driven gear receiving 50 g of driving force
Is provided. The screw shaft 50h has an axial direction,
Both the rotation direction is fixed to the engine case 38,
When the actuator driven gear 50g rotates, the actuator driven gear 50g moves forward and backward on the axis of the screw shaft 50h in the direction of the drive pulley shaft 34a, so that the belt winding diameter of the drive pulley 50 can be changed. I have. The detection end of the drive pulley position sensor 50s is attached to the actuator driven gear 50g for detecting the diameter of the pulley 50. Also, as shown in FIG. 8, the actuator motor 64 and the reduction gear trains 66a to 66c are specifically No. 1 meshing with a pinion gear fixed to a drive shaft 64a of the actuator motor 64.
Actuator idle gear (driven gear) 66
a, a No. 2 actuator idle gear (driven gear) 66b that meshes with the No. 1 idle shaft fixed drive gear, and a No. 2 idle shaft fixed drive gear 66c. The drive gear 66c meshes with the actuator driven gear 50g to form a gear. The rotational driving force sequentially decelerated in the row drives the driven gear 50g and thus the diameter of the drive pulley 50 to be changed.

Here, the point that the cleaner 86 for the cooling fan of the V-belt transmission 34 and the air cleaner 68 are provided integrally will be described. V-belt transmission 34
The outside air is introduced into the V-belt chamber 34c as cooling air by a cooling fan 88a provided on the outer surface (the right side in the embodiment) of the fixed face 54f of the driven pulley 54, and the cooling fan is A duct 88b is provided. A hose 88c is connected to the cooling fan duct 88b.
Outlet 8 of cleaner 86 for cooling fan through
6b to prevent intrusion of dust and moisture in the air. More specifically, as shown in FIGS. 5 to 7, a relatively short cooling fan cleaner 86 case is integrally formed on the right side surface of an air cleaner 68 case extending in the front-rear direction via a partition wall. It is mounted and arranged on the upper part of the reference numeral 34. Each of the inlet openings 68a and 86a of the air cleaner 68 and the cooling fan cleaner 86 faces forward and parallel to each other.

As shown in FIG. 6, the air cleaner 68 is divided into two upper and lower chambers by a partition wall 68b, and has an inlet opening 68a toward the front of the vehicle body in the upper chamber. A filter body 68c is provided so as to surround the periphery, and the clean air passing through the filter body 68c is directed forward from an outlet 68d to an intake pipe 90 of the engine 32 and further to the cylinder head 32.
It communicates with the intake port 92 of a. Reference numeral 96 denotes a throttle valve, and 98 denotes a fuel injector (fuel injection valve).

As shown in FIG. 7 along the line VII-VII in FIG. 6, the cooling fan cleaner 86 includes an inlet 86a.
A filter 86c is disposed at the back of the vehicle and passes through a partition 86e having a hole 86d, and an outlet 86b in the right direction of the vehicle body.
From the cooling fan.

The case of the air cleaner 68 and the case of the cooling fan cleaner 86 are integrally formed. Since the air cleaner 68 and the cooling fan cleaner 86 are arranged at the same location, the number of locations where other parts are disassembled can be reduced, and at the same time maintenance can be performed, thereby reducing man-hours. In addition, since maintenance can be performed at the same time, forgetting of maintenance of the cooling fan cleaner 86 can be particularly prevented. Furthermore, since the filter is integrated, a large filter capacity can be set, and weight and cost can be reduced. The upper part of the partition walls 68b and 86e forms an integral cap 100 which is detachable from the case. This makes it possible to perform maintenance on both caps simply by removing one cap 100, which is convenient.
Further, the cap is arranged on the upper surface side so as to face the bottom surface of the sheet 12, and no components are arranged between the sheet and the cap. In this way, sheet 1
Since the cap 100 can be opened and closed simply by opening the cover 2, maintenance such as replacement of the filter becomes extremely easy.

According to the embodiment, in the engine storage tunnel portion 30a which is higher than the footrest floor surface 40,
Cylinder head 32a, cylinder 3 below foot space 14
The width of the tunnel part for storing 2b is the cylinder head 32.
a, because it can be made relatively narrow due to the cylinder 32b,
The rider floor surface 40 can be loosely provided on both sides of the tunnel without making the entire width of the frame cover 30 too large. The cylinder head 32a, the cylinder 3
A rotary pump, such as a crankshaft, a V-belt transmission and a balancer shaft, which is wider than 2b;
Since the rotary motion part such as the balancer shaft that also serves as the drive of the oil pump is housed in the part where the width under the seat becomes wide,
The design is reasonable and the appearance is good. Further, the pillion floor 41 comes to both sides, but since it is located higher than the rider floor surface 40, the bank angle is not affected even if the width is wide. Moreover, the windage resistance is small. In addition, the end of the mag cover 38d, which is the widest in the engine case 38, and the end of the cover 38e of the primary drive sprocket portion can be disposed below the floor surface 40, so that the wide case can be easily accommodated. In addition, since the mass can be concentrated near the vehicle weight center below the floor 40 and the seat 12, the running stability is improved. Further, the engine V-belt transmission 3 is located forward of the unit swing type engine unit.
4. Since a heavy object such as the balancer shaft 36 can be arranged, it is easy to take a load sharing the front and rear with good running performance even at a high speed.

Since the inclination angle of the engine cylinder 32b is set to a substantially horizontal forward rising inclination, the foot space 14
The bottom can be lowered so that the foot can be easily passed. Further, since the cylinder shaft is substantially horizontal, even when secondary vibration is generated in the direction of the cylinder axis, vibration is hardly generated on the handle, the seat 12, and the floor 40.

Further, since the balancer shaft 36 of the engine 32 is disposed substantially behind the vehicle body on the cylinder shaft, parts requiring oil lubrication can be disposed immediately above the oil pan 38b, so that the oil passage can be shortened and the oil passage can be shortened. Road resistance is reduced, and a small oil pump can be used. In addition, since it is lower than the surface of the pillion rider floor 41, the width can be increased, and a water pump 44 and an oil pump 42 are provided on both sides.
Can be arranged, so that a transmission device dedicated to the pump is not required. This is because it can be shared with the drive of the balancer shaft 36.

An oil pump 42 and a water pump 44 are disposed at both ends of the balancer shaft 36, respectively, and are driven by the balancer shaft 36. The drive pulley shaft 34a of the V-belt transmission 34
And the driven pulley shaft 34b is arranged so that an axis passing through the axis thereof is parallel to the cylinder axis Sp (if it is parallel in design) and above the crankshaft. The V-belt transmission 34, which is wider than the cylinder head and cylinder but narrower than the crankshaft, can be arranged above the floor 40 and below the seat 12, which can be wider than the foot space.

A starter clutch 56 or a drive pulley rotational speed sensor rotor 58a is provided on the drive pulley shaft 34a between the pulley 50 of the drive pulley shaft 34a of the V-belt transmission 34 and the primary drive sprocket 48, and these are connected to the crankshaft. The width of the engine can be narrower than that of the engine.

Crank shaft 32c, drive pulley shaft 3
Since the starter motor 62 is disposed in the space between the cylinder 4a, the cylinder 32b, and the intake pipe 90, the space can be used effectively, the engine unit can be reduced in size, and the area around the vehicle seat can be made compact.

The actuator motor 64 of the V-belt transmission 34 and its reduction gear trains 66 a to 66 c are arranged above the V-belt transmission 34. Accordingly, the air cleaner 68 can be disposed on the side surface because the width is narrow.

On the upper side of the V-belt transmission 34, the actuator motor 64 and its reduction gear trains 64a-64
c, an air cleaner 68 is provided on the side surface thereof, and the opening 68a of the inlet 68a of the air cleaner 68 is covered with the body cover 30.
It is arranged on the 4 side. By using a cleaner having a large volume but a light weight per volume, it is possible to arrange the cleaner so that the weight per volume is heavy on the lower side and lighter as it goes up, so that the center of gravity can be lowered. In addition, since the inlet 68a can be opened at a position on the rear standing surface 14r where mud and dust do not enter, the life of the filter is increased and a change in setting can be reduced.

A cushion unit 78 is disposed substantially upright behind the pivot shaft 24 at the front end pivot of the swing arm 22.
And a battery case in a space surrounded by the rear end of the engine case 38 of the engine unit and the cushion unit 78 and the pivot shaft 24 or the suspension shaft of the engine case and the lower surface of the seat 12 integrally provided with the reduction gear trains 64a to 64c and the like. 82 are provided. Thereby, the space can be effectively used, and the body can be made compact.

Further, since the starting clutch 52 is provided between the universal joint 72 and the final drive bevel gear, the width of the engine unit can be made narrower and the space below the seat can be made compact as compared with the method of providing the clutch between the driven pulley and the secondary drive gear. . Further, the width direction of the swing portion can be made narrower than a general swing type in which a centrifugal clutch is provided near the rear wheel by a unit swing type. If the starting clutch 52 is provided near the pivot shaft, the unsprung weight does not increase so much.

The V-belt chamber 34c of the V-belt transmission 34
Is provided integrally with the air cleaner 68 for the engine 32. Thus, since the maintenance of the air cleaner 68 filter and the filter for the cooling fan is performed at the same place, disassembly of other parts is reduced, and at the same time maintenance can be performed, thereby reducing man-hours.

[0050]

As described above, according to the present invention, the steering stability can be improved by centralizing the position of the center of gravity, and the center of gravity can be positioned at the center of the front and rear of the vehicle. The width can be reduced, and the space under the seat can be used effectively.

[Brief description of the drawings]

FIG. 1 is an overall side view illustrating a scooter type motorcycle according to an embodiment.

FIG. 2 is a plan view of the same.

FIG. 3 is a side view illustrating an engine and a drive mechanism at a rear portion of the vehicle.

FIG. 4 is a cross-sectional view along a cylinder axis for explaining an engine and a drive mechanism at a rear portion of the vehicle.

FIG. 5 is an explanatory cross-sectional detailed view along each pulley shaft of the V-belt transmission.

FIG. 6 is an explanatory longitudinal sectional view of a cleaner for an air cleaner cooling fan.

FIG. 7 is an explanatory diagram of the cooling fan cleaner taken along line VII-VII in FIG. 6;

FIG. 8 is an explanatory cross-sectional view of an actuator for a V-belt transmission and a gear train thereof along a line VIII-VIII in FIG. 3;

[Explanation of symbols]

 Reference Signs List 8 rear wheel 10 frame head pipe 10 12 rider's (driver's) seat 12a seat upper surface 14 foot space 16 front wheel 20 frame 22 rear swing arm 24 pivot shaft 30 body cover 30a tunnel section 32 engine 34 V-belt transmission 34a drive Pulley shaft 34b Driven pulley shaft 34c V belt chamber 36 Balancer shaft 38 Engine case 40 Footrest floor 42 Oil pump 44 Water pump 50 Drive pulley 52 Start clutch 54 Driven pulley 64 Actuator motor 66a-66c Reduction gear train 68 Air cleaner 78 Cushion unit 86 Cooling fan cleaner

Claims (12)

[Claims] 1. A vehicle in which a foot space lower than a seat upper surface is provided between a frame head pipe and a rider's seat, at least a part of a cylinder head and a cylinder are disposed below the foot space in a side view, and a rider is provided. A scooter-type motorcycle characterized in that rotating parts such as a crankshaft, a V-belt transmission, and a balancer shaft are arranged below a seat for use. 2. The scooter-type motorcycle according to claim 1, wherein an inclination angle of the engine cylinder is set to a substantially horizontal forward rising inclination. 3. The engine according to claim 1, wherein the balancer shaft of the engine is disposed substantially behind the crankshaft on the cylinder shaft.
Or the scooter type motorcycle according to 2. 4. An oil pump and a water pump are respectively disposed at both ends of a balancer shaft, and are driven by the balancer shaft.
The scooter-type motorcycle according to any one of the above. 5. The V-belt transmission according to claim 1, wherein an axis passing through the axis of the drive pulley shaft and the driven pulley shaft is arranged in parallel with the cylinder axis and above the crankshaft. A scooter-type motorcycle according to any one of claims 1 to 4. 6. A V-belt transmission, wherein a starter clutch (56) of an engine starting device or a sensor rotor of a drive pulley rotation sensor is provided between a drive pulley on a drive pulley shaft and a primary drive sprocket. A scooter-type motorcycle according to claim 5. 7. The scooter-type motorcycle according to claim 5, wherein a starter motor is disposed in a space between the crankshaft, the drive pulley shaft, the cylinder, and the intake pipe. 8. The scooter-type motorcycle according to claim 5, wherein the shift actuator motor of the V-belt transmission and the reduction gear train thereof are arranged above the V-belt transmission. 9. An air cleaner is provided on the side of the actuator motor and its reduction gear train above the V-belt transmission, and the inlet opening of the air cleaner is located behind the foot space below the seat covered by the body cover. The scooter-type motorcycle according to claim 5, wherein the motorcycle is disposed on an elevation side. 10. A cushion unit is disposed substantially upright behind a pivot shaft which pivotally supports a front end of a swing arm,
A battery is disposed in a space surrounded by an engine case of an engine unit integrally provided with a V-belt transmission and the cushion unit and a pivot shaft of a swing arm or a suspension shaft of the engine case and a seat lower surface. A scooter-type motorcycle according to claim 5. 11. The scooter-type motorcycle according to claim 1, wherein the starting clutch is provided between the universal joint and the final drive bevel gear. 12. The scooter-type motorcycle according to claim 1, wherein a cleaner for a cooling fan of a V-belt chamber of the V-belt transmission is provided integrally with an air cleaner of the engine.