JP2533295B2 - Scooter type motorcycle - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scooter-side motorcycle having an undercover on the lower surface of a footrest and a main stand attached to the lower surface of a unit swing type power unit.

(Background of the Invention) In a scooter type motorcycle equipped with a unit swing type power unit, power is supplied from below the footrest in order to reduce air resistance and to cool an exhaust muffler in a rear cover surrounding the power unit. It is considered that an under cover that covers the lower front of the unit is attached so that the running air is guided between the footrest and the under cover to the inside of the rear cover or around the exhaust muffler. However, when installing the main stand on the bottom of the power unit so that it can be erected,
The undercover could not be extended far enough to avoid interference with the main stand. For this reason, there is a problem that the function of the under cover such as reduction of air resistance and cooling of the inside of the rear cover and the vicinity of the exhaust muffler is sacrificed to some extent.

Therefore, it is considered that the traveling wind is taken from the front between the footrest and the undercover and guided into the rear cover. In this case, it is conceivable that the rear part of the footrest is raised rearward and the rear part of the undercover is lowered rearward so that the cooling air widely flows in the rear cover. However, when the rear part of the undercover is lowered rearward, the rear part of the undercover approaches the road surface, resulting in a decrease in road clearance.

(Object of the Invention) The present invention has been made in view of such circumstances,
An object of the present invention is to provide a scooter type motorcycle that can substantially extend the rear edge of the under cover to reduce air resistance, improve the cooling performance in the rear cover, and ensure a large road clearance.

(Constitution of Invention) According to the present invention, an object of the present invention is to provide a unit swing type power unit in which one rear wheel is held inside a rear portion of a transmission case extending from one side of an engine to a rear side and the front portion is axially supported by a vehicle body frame. An exhaust muffler disposed on the opposite side of the automatic transmission case across the rear wheel, an operating seat located above the power unit, and a substantially flat footrest located below the operating seat. A rear cover that covers the upper part of the power unit and is continuous with the footrest, an undercover that is attached to the lower surface of the footrest and guides the running wind from the lower front part of the footrest into the rear cover, and the rear cover. Equipped with a cooling air outlet opening in the upper part and a main stand that is attached to the lower surface of the front part of the power unit so that it can be tilted up and down with the front end as a fulcrum and the rear end extends to the vicinity of the front edge of the rear wheel in side view. In a scooter type motorcycle, the rear part of the footrest is raised rearward and the rear part of the undercover is rearward lowered, while the rear edge of the undercover is stepped upward in a side view step shape to the vicinity of the front end of the main stand. When the main stand is stored, the rear edge of the under cover is closed, and the rear edge of the under cover is close to the front edge of the rear wheel, and both sides of the rear edge extend rearward in a substantially circular shape in plan view. This is achieved by a scooter type motorcycle characterized in that an engine cover formed in an arc shape is attached to the main stand, and the rear cover is continuous with the side rear edge of the under cover while covering the side of the rear wheel in a side view. It That is, when the main stand is stowed, the engine cover closes the opening to reduce air resistance, and the rear lower part of the under cover is stepped up in a stepped shape in side view to the side of the power unit that moves up and down with the rear wheels. Since the engine cover attached to is used to close it, sufficient road clearance can be secured.

(Embodiment) FIG. 1 is one embodiment of the present invention, a left side view of a scooter type motorcycle having a unit swing type rear wheel suspension device, FIG. 2 is a partially enlarged side view thereof, and FIG. It is a bottom view.

In FIG. 1, reference numeral 10 is a frame. The frame 10 includes a steering shaft tube 12, a front frame 14, and a pair of left and right rear frames 16 (only one is shown) extending obliquely upward and rearward from the lower end of the front frame 14.

Reference numeral 18 denotes a power unit in which a forced air-cooled two-cycle engine 20 and a transmission case 22 extending from the left side of the engine 20 to the rear are integrally assembled. A front portion of the transmission case 22 is vertically swingably connected to the rear frame 16 via a link 24. The rear portion of the transmission case 22 is elastically supported by the buffer unit 26. 28 is a rear wheel attached to the rear part of the transmission case 22, 30 is an intake air purifier attached to the upper surface of the transmission case 22, and 32 is arranged on the opposite side of the transmission case 22 with the rear wheel 28 interposed. It is an exhaust muffler.

A fuel tank 34 is fixed to the rear frame 16 so as to be located above the power unit 18.
Reference numeral 36 is a lubricating oil tank mounted behind the fuel tank 34. A steering shaft (not shown) is rotatably held in the steering shaft cylinder 12, and a steering bar handle 38 is fixed to the upper end of the steering shaft. A handle cover 40 is attached to the steering bar handle 38, and a windshield 42 is provided at the upper center of the handle cover 40.

A pair of left and right front forks 44 is fixed to the lower end of the steering shaft, and front steering wheels 46 are rotatably attached to the front forks 44 via a bottom link type suspension device. A substantially hemispherical wheel cover 48 that covers the left and right side surfaces of the front wheel 46 is attached to the front fork 44 to reduce air resistance.

50 is a driving seat. The driving seat 50 includes a backrest portion 52 that supports the vicinity of the lumbar vertebra of the driver.

Reference numeral 54 is a substantially flat plate-shaped footrest located below the steering bar handle 38 in the handlebar cover 40 and the driver's seat 50, and the upper part of the footrest space crosses the vehicle body in the left-right direction.
It is 56. Reference numeral 58 is a rear cover that covers the upper side of the power unit 18 and the rear wheel 28, and 60 is a leg shield that covers the front portion of the steering shaft tube 12 and the front frame 14 from the front and rear. 62
Is a tail light incorporated in the lower rear portion of the rear cover 58.

The rear cover 58 and the lower edge of the tail lamp 62 are formed substantially linearly from the rear of the footrest 54 toward the upper rear, and a rear fender 64 is fixed to the lower edge. The rear fender 64 and the rear cover 58 form a rear cover that covers the power unit 18 and covers the footrest 54.

66 is an undercover. The undercover 66 has a front part that covers the lower part of the footrest 54 and a rear part that is a power unit.
It is fixed so as to cover the lower part of 18. Foot rest here 54
The rear portion of the rear cover is inclined upward and the rear portion of the under cover 66 is inclined downward. As a result, the cooling air inlet 76, which will be described later,
Therefore, the traveling wind (cooling wind) entering between the footrest 54 and the under cover 66 flows into the rear cover while spreading vertically.

As shown in FIG. 2, an opening 68 is formed in the rear portion of the under cover 66 and is cut out in a U shape so as to open rearward. A main stand 70 is arranged above the opening 68. ing. That is, the main stand 70 is rotatably attached to the lower surface of the front portion of the power unit 18 by a lateral shaft 72 (FIG. 3), and is housed in a substantially vertical standing position (the phantom line position in FIG. 3) and in a substantially horizontal storage position. It can be tilted up and down between the position and the position of the solid line. The rear end of the main stand 70 is located near the front edge of the rear wheel 28 in a side view in the stored state. Further, the opening 68 is notched upward in a stepped manner in a side view, and the undercover 66 is opened sufficiently larger than a portion where the undercover 66 overlaps the up and down trajectory of the main stand 70. Main stand 70
Is stabilized in its upright and stowed position by a tension coil spring (not shown).

74 is an engine cover for opening and closing the opening 68, and is fixed to the main stand 70. The surface of the engine cover 74 extends rearward and downward almost continuously with the outer surface of the under cover 66 when the main stand 70 is stored. Further, the under cover 66 is equivalent to being extended to just before the rear wheel 28 by the engine cover 74. Here, the rear edge of the engine cover 74 is formed in a substantially arcuate shape in a plan view so as to approach the rear wheel, and one side thereof faces below the exhaust muffler 32.

Between the front end of the under cover 66 and the footrest 54, the front wheel 46
A cooling air inflow port 76 having a large opening behind is formed. The rear cover 58 rises upward from the rear of the operation seat 50, and a cooling air exhaust port 78 is opened here.

Therefore, when traveling with the main stand 70 stored, a large amount of engine cooling air enters from the cooling air inlet 76, passes between the footrest 54 and the under cover 66, and is guided to the rear part that spreads above and below both. Enter the inside of the rear cover 58 while expanding vertically. A part of this cooling air is used for cooling the engine 20, and the cooling air after cooling the engine and the cooling air newly introduced from the cooling air inlet 76 are mixed with each other, and a part thereof rises in the rear cover 58. Then, it is exhausted from the exhaust port 78 by utilizing the negative pressure generated behind the driver. The remaining portion is discharged rearward from the rear edge of the engine cover 74 that substantially forms a part of the under cover 66 or the lower opening of the rear fender 64. The rear edge of the engine cover 74 is also formed in a substantially arcuate shape in a plan view, and one side thereof faces below the exhaust muffler 32 and the other side thereof faces below the transmission case 22, respectively. Cooling is also performed. Since the running wind flows along the outer surfaces of the under cover 66 and the engine cover 74 during running, the engine cooling air inside the rear cover 58 is satisfactorily sucked out from the vicinity of the rear edge opening, and the transmission case
22 and muffler 32 or rear wheel 28 brakes (not shown)
And so on.

Further, in a state where the vehicle is stopped and the main stand 70 is erected, the opening 68 of the under cover 66 is greatly opened, and hot air in the rear cover 58 is easily discharged from the exhaust port 78 at a high position and cold outside air is easily introduced. To ensure cooling when the vehicle is stopped.

(Effect of the Invention) As described above, according to the present invention, an opening cut out to the vicinity of the front end of the main stand is provided at the rear edge of the under cover attached to the lower surface of the footrest, and this opening is provided on the main unit side of the power unit. Since it is closed by the engine cover attached to, the air resistance during traveling is reduced. Further, the traveling wind that has passed between the footrest and the undercover and entered the rear cover enters the inside of the rear cover while spreading along the vertically expanded space at the rear part between them. Then, the cooling air warmed by the heat of the engine is smoothly exhausted from the exhaust port at a high position, and the cooling property in the rear cover is also improved.
Furthermore, the rear part of the under cover is inclined downward, but an opening notched upward in a side view step shape is provided at this rear edge, and this opening is fixed to the side of the power unit that moves up and down together with the rear wheel. Since the engine cover closes, the engine cover also moves up and down with the rear wheels. Therefore, it is possible to secure a sufficiently large road clearance.

Also, if the main stand is erected, the engine cover can be opened, and it is possible to install the main stand even though it is a substantially long rear undercover. At this time, the front part of the power unit is pivotally supported by the body frame, and the main stand is attached to the lower surface of the front part of the power unit. The relative movement amount becomes smaller. Therefore, the gap between the opening and the engine cover can be reduced.

Furthermore, when standing up and stopping the main stand,
The wide engine cover wide in the width direction of the vehicle body opens downward, so hot air in the under cover and rear cover rises in the rear cover and is easily discharged from the exhaust port, and cold outside air easily enters, improving the cooling performance of the engine etc. be able to. Also, while running, the muddy water splashed by the rear wheels is likely to adhere to the upper surface of the engine cover, the upper surface of the under cover, and the inner surface of the rear cover that are close to the front edge of the rear wheel, and the mud tends to adhere to the outer surface of these. It is hard to get dirty and the appearance is hard to get dirty. By raising the main stand, the dirt on the upper surfaces of the engine cover and the rear cover and the inner surface of the rear cover can be easily washed away. Since the center of the engine cover in the width direction is brought close to the front edge of the rear wheel and both sides thereof are extended rearward, traveling wind can be guided around the exhaust muffler and the transmission case to improve their cooling performance.

Furthermore, since the rear portion of the under cover is inclined rearward and downward, the muddy water that has entered the cooling air inlet along with the traveling wind therein is guided to the inclined surface of the under cover and is discharged while the vehicle is stopped. Therefore, the auxiliary devices in the rear cover are not polluted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a left side view of an embodiment of the present invention, FIG. 2 is a partially enlarged side view thereof, and FIG. 3 is a bottom view. 18 …… power unit, 28 …… rear wheel, 46 …… front wheel, 50 …… driving seat, 54 …… footrest, 58 …… rear cover that is a part of rear cover, 64 …… a part of rear cover There is a rear fender, 66 …… under cover, 68 …… opening, 70 …… main stand, 74 …… engine cover.

Claims (1)

(57) [Claims] 1. A unit swing type power unit in which one rear wheel is held inside a rear portion of a transmission case extending from one side of an engine to a rear side and a front portion is pivotally supported by a vehicle body frame, and the transmission is performed with the rear wheel interposed therebetween. An exhaust muffler arranged on the opposite side of the case, an operating seat located above the power unit, a substantially flat footrest located in front of and below the operating seat, and the foot covering the upper part of the power unit. A rear cover continuous to the stand, an under cover attached to the lower surface of the foot stand to guide traveling wind from the lower front part of the foot stand into the rear cover, and a cooling air exhaust port opened at the upper rear part of the rear cover. A scooter-type motorcycle having a main stand, which is attached to the lower surface of the front portion of the power unit so that it can be tilted up and down with the front end as a fulcrum, and the rear end extends to the vicinity of the front edge of the rear wheel when viewed from the side. The rear part of the footrest rises backward and the rear part of the undercover moves downward, while the rear edge of the undercover has an opening notched upward in a side view stepwise up to the vicinity of the front end of the main stand. An engine in which the opening of the under cover is closed when the main stand is housed and the rear edge is formed in a substantially arc shape in plan view so that the center in the width direction approaches the front edge of the rear wheel and both sides thereof extend rearward. A scooter-type motorcycle, wherein a cover is attached to the main stand, and the rear cover covers the side of the rear wheel in a side view and is continuous with the side rear edge of the under cover.