JPS6322788A - Rear-wheel gearing system cooling device for car - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Applicability ￥f) The present invention relates to a rear wheel transmission system cooling device for a vehicle in which a belt transmission device is housed in a transmission case that forms a power unit together with an engine. .

(Background of the Invention) In vehicles such as scooters that have a unit swing type rear wheel suspension, the engine and transmission case form a power unit, and a belt transmission device housed in the transmission case transfers the engine rotation to the rear wheels. There is more to convey than before. It is desirable that this (1) belt transmission device be cooled by outside air in order to prevent damage to the V-belt or the like due to heat generation.

Therefore, it has been considered to provide the transmission case with an outside air introduction cover that forms an outside air introduction path to guide cooling air into the transmission case. In this case, in order to prevent dust from being sucked into the transmission case, it has been considered to provide a filter element in the outside air introduction path (for example, Japanese Patent Application No. 59-39752, Japanese Patent Application Laid-open No. 59-195018).
.

From the viewpoint of removing clumps, a wet type filter element impregnated with oil is desirable.

However, in a belt transmission device, it is absolutely necessary to avoid oil from adhering to the belt, so the amount of oil impregnated into the filter must be strictly controlled so that it does not become excessive, resulting in troublesome maintenance.

On the other hand, if a dry type filter element is to remove even fine dust, a fine filter must be used, making it more likely to become clogged. Furthermore, if the mesh is coarse enough to prevent clogging, there will be a problem in that fine dust will not be captured sufficiently.

(Purpose of the Invention) The present invention has been made in view of the above circumstances. When a filter element is provided in the outside air introduction path that leads outside air into the transmission case, the filter element can be easily maintained and To provide a cooling device for a rear wheel transmission system of a vehicle, which has low resistance, is hard to be clogged, and can reliably capture fine dust.

(Structure of the Invention) According to the present invention, this object is to hold a rear wheel at the rear end of a moving canine formed by an engine and a transmission case, and to hold a rear wheel at the rear end of a moving canine formed by an engine and a transmission case, and to hold a rear wheel at the rear end of a moving cannier formed by an engine and a transmission case, and to hold a rear wheel at the rear end of a drive canine formed by an engine and a transmission case. In a vehicle in which a fan for sucking outside air is provided in a transmission case, and an outside air introduction cover is attached to the transmission case to form an outside air introduction path for guiding outside air to the fan, a plate-shaped dry filter element is provided in the outside air introduction path. This is achieved by a rear wheel transmission system cooling device for a vehicle, characterized in that the filter element is formed to have finer mesh on the downstream side than on the air inflow side.

(Example) Fig. 1 is a side view of a scooter to which an embodiment of the present invention is applied, Fig. 2 is a partially sectional exploded plan view of its power unit, and Fig. 3 is a partially sectional view of the outside air introduction cover. Figure 4 is a side view of the front of the transmission case with the outside air introduction cover removed, Figure 5 is a sectional view taken along the ■-■ line in Figure 1, and Figure 6 is the same <VT-VI. The line sectional view, FIG. 7, is an enlarged sectional view of the first filter element.

In FIG. 1.2, the reference numeral 10 denotes a power unit, which includes a forced air-cooled two-stroke single-cylinder engine 12 and a transmission case 14 that extends rearward from the left side of the carrot 12 and is integrated with the engine 12. A rear wheel 16 is held on one side of the rear portion of the transmission case 14, that is, on the right side.

A belt transmission device 18 that transmits the rotation of the engine 12 to the rear wheels 16 is housed within the transmission case 14 . The front end of the power unit 10 is connected to a vehicle body frame (not shown) so as to be vertically swingable, and the rear end is elastically supported by a cushion unit 20.

A magneto generator 24 is attached to the right end of the horizontally placed crankshaft 22 of the engine 12, and a fan 26 is fixed to the flywheel of this power generator a24 to which a magnet is fixed. The fan 26 draws outside air into the cover 28 from a cooling air intake port 30 provided in the engine cover 28, and forcibly cools the engine 12. This engine cooling air flows through a duct 32 (
1) and is discharged to the lower left front of the power unit 10.

A drive pulley 34 of the belt transmission device 18 is attached to the left end of the crankshaft 22. This pulley 34 includes a movable pulley half 34a that slides on the crankshaft 22,
A fixed pulley half 34b that faces the pulley half 34a and is fixed to the end of the crankshaft 22 is provided. The movable pulley half 34a is pressed toward the fixed pulley half 34b by the roller 36 with a pressing force depending on the rotation speed, and both halves 34a
, 34b, the winding radius of the V-belt 38 increases as the rotational speed increases. The rotation of the driving pulley 34 is transmitted to the rear wheel shaft 46 via the V-belt 38, the driven pulley 40, the centrifugal clutch 42, and the reduction gear 44. Note that the driven pulley 40 is biased in a direction in which the interval between its respective pulley halves decreases, and this interval changes in accordance with changes in the belt winding radius of the driving pulley 34.

A fan 48 is integrally formed on the outer surface of the fixed pulley half 34b of the driving pulley 34. A partition plate 50 facing the fan 48 is mounted inside the transmission case 14, and a circular opening 52 facing the center of the fan 48 is formed in the partition plate 50. A kick-type starter 54 is disposed near this opening 52.

This kick-type starting device 54 includes a fixed meshing gear 56 fixed to the left end of the crankshaft 22, and a shaft 58 opposite thereto.
A movable meshing gear 60 that can be slid on the top in the axial direction, a helical gear 62 integrally formed with the movable meshing gear 60, and a stopper 6 that adds resistance to the rotation of the movable meshing gear 60.
4, a kick shaft 66, a double helical gear 68 fixed to the kick shaft 66 and meshing with the double helical gear 62, a kick pedal 70 fixed to the kick shaft 66, and a kick shaft 66.
1.3.4, a torsion spring 72 is provided which provides a counterclockwise return behavior. The helical gears 62 and 68 are made so that when the kick pedal 70 is depressed, the helical gears 62, which are given resistance by the resistance ring 64, are sent out toward the fixed meshing gear 56. Therefore, when the kick pedal 70 is depressed, the movable meshing gear 6
0 engages with the fixed meshing gear 56, the crankshaft 22 is rotated counterclockwise in FIG. 1.3.4, and the engine 12
It becomes possible to start.

The partition plate 50 is interposed between the fan 48 and the gears 62 and 68.

A window 74 is formed on the other side of the transmission case 14, that is, on the side opposite to the rear wheel 16, at a position facing the fan 48 and the opening 52 of the partition plate 50. This transmission case 1
An outside air introduction cover 76 is attached to the other side of 4.

The outside air introduction cover 76 is located inside the outer shape of the transmission case 14 when viewed from the side, and is formed to cover the window 74 of the transmission case 14 . This outside air introduction cover 76 forms an outside air introduction path 78 together with the transmission case 14, and this outside air introduction path 7
8 opens from above the externally protruding end of the kick shaft 66, pointing downward, and serves as an outside air introduction port 80. An eaves plate 82 is integrally formed on the outside air introduction cover 76 and extends obliquely downward and forward from the rear edge of the outside air introduction port 80, passing outside the protruding end of the kick shaft 66.

Reference numeral 84 denotes a first filter element with a coarse mesh, which is vertically disposed within the outside air introduction cover 76. That is, inside the outside air introduction cover 76, a pair of upper and lower grooves 86.88 are formed at positions close to the outside air introduction port 80, and these grooves 86.
The element 84 is attached to 88.

90 is a second filter element, and transmission case 1
4 and the outside air introduction cover 76, and the window 74
is covered. As shown in FIG. 7, this second element 90 has a finer mesh from a surface 90a on the outside air introduction cover 76 side to a surface 90b on the transmission case 14 side, that is, on the downstream side than on the air inflow side. It has become. This element 9o can be made, for example, by using open-cell polyurethane foam with a coarse mesh and pressing the side surface of the foam against a heated metal plate to make the mesh fine. In addition, a water drain hole 92 (Fig. 3.6) is provided in the groove 88 into which the lower edge of the first element 84 is inserted, and a water drain hole is provided in the lower part of the outside air introduction cover 76 that clamps the second element 90. 94(
3.5) are formed respectively.

In FIG. 2, 96 is a duct located behind the kick shaft 66, and there is a discharge port 9 that opens downward.
8 is formed.

In FIG. 1, 100 is an intake air purifier for the engine 12 fixed to the upper surface of the transmission case 14, 102 is a rear cover, 104 is a driver's seat, 106 is a front wheel, 108 is a steering wheel/hook, 110 is a leg shield, and 112 is a It is a flat footrest.

According to this embodiment, the rotation of the crankshaft 22 rotates the driving and driven pulleys 34, 40, and when the speed reaches a certain level or higher, the centrifugal clutch 42 is connected and the rear wheel 16 rotates. As the drive pulley 34 rotates, the fan 48 sucks outside air into the transmission case 14 through the outside air introduction path 78.

At this time, the first element 84 mainly removes water droplets.

Air passing through first element 84 enters second element 90. Since this element 90 has finer meshes in the direction of air flow, large dust is captured near the upstream surface 9Oa, and fine dust is captured near the downstream surface 90b. In this way, the dust is widely spread in the thickness direction within the element 90 according to its size, and is not concentratedly captured on one surface. As a result, it is less likely to become clogged, and it also reliably captures fine dust. The outside air that has entered the transmission case 14 cools the transmission device 18 and is discharged to the outside from the exhaust port 98.

In this embodiment, first and second filters 84 and 90 are provided, and the first filter 84 has a coarse mesh to mainly remove water, so water is less likely to adhere to the second filter 90. Therefore, the suction resistance for four people does not increase due to adhesion of water. However, in the present invention, the first filter 8
Of course, it is also possible to omit 4.

Note that the present invention includes not only filters in which the mesh gradually becomes denser in the direction of air flow, but also filters in which the fineness of the mesh changes discontinuously. .

(Effects of the Invention) As described above, the present invention provides a plate-shaped dry filter element in the outside air introduction path that guides outside air into the transmission case.
Maintenance is easier compared to the wet type. In addition, since this filter element has finer mesh on the downstream side than on the air inlet side, the particles are dispersed widely in the thickness direction of the element and are not captured in a concentrated manner on the surface of the element. This prevents the element from clogging, making it difficult to use for long periods of time. In addition, the fine grains near the surface in the direction of air flow ensure that even fine dust can be captured.

[Brief explanation of the drawing]

Fig. 1 is a side view of a scooter to which an embodiment of the present invention is applied, Fig. 2 is a partially sectional exploded plan view of the power unit, and Fig. 3 is a front view of the transmission case with the outside air introduction cover partially sectional. Figure 4 is a side view of the front part of the transmission case with the outside air introduction cover removed, Figure 5 is a sectional view taken along the ■-v line in Figure 1, and Figure 6 is the same sectional view taken along the <Vl-Vl line. be. 7th
The figure is an enlarged sectional view of the first filter element. DESCRIPTION OF SYMBOLS 10... Power unit, 12... Engine, 14... Transmission case, 16... Rear wheel, 18... Belt transmission device 35... Drive side pulley, 40... Driven side pulley, 48...Fan, 76...Outside air introduction cover, 78...Outside air introduction path, 90...Second filter element. Patent applicant Yamaha Motor Co., Ltd. Agent Patent attorney Yama 1) Fumio Figure 5

Claims (1)

[Claims] A rear wheel is held at the rear end of a power unit formed by an engine and a transmission case, and a pulley of a belt transmission device housed in the transmission case has a fan that draws outside air into the transmission case. In the vehicle, the transmission case is equipped with an outside air introduction cover that forms an outside air introduction path that guides outside air to the fan, and the outside air introduction path is provided with a plate-shaped dry filter element, and this filter element A cooling device for a rear wheel transmission system of a vehicle, characterized in that a cooling device for a rear wheel transmission system of a vehicle is formed so that the openings on the downstream side are finer than on the inlet side.