JP2003042270A - Cooling structure of belt transmission - Google Patents

Abstract

(57) [Problem] To provide a cooling structure for a belt transmission of a motorcycle, which prevents water from entering a belt chamber from a deep puddle or the like. SOLUTION: A driving sheave connected to a power source and a driven sheave connected to an axle are wound around a V-belt and housed in a belt chamber, and an intake port 15 and an exhaust port 45 for outside air are provided in the belt chamber. In a cooling structure of a belt transmission for a motorcycle, in which outside air for cooling is circulated into a belt chamber through an inlet port 15 and an outlet port 45, an inlet port 15 and an outlet port 45 for the outside air are formed at the upper front and rear sides of the belt chamber, respectively. did.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling structure for a belt transmission of a motorcycle. The motorcycle includes small motorcycles such as scooters and motorbikes, and electric motor driven motorcycles.

[0002]

2. Description of the Related Art A swing unit type engine is used as a drive device for a small motorcycle. This swing unit type engine has a V crankcase for the engine.
A belt-type transmission is integrally connected and attached to a rear wheel, and is attached to the body frame together with the rear wheel via a shock absorber so as to be swingable. The transmission has a drive sheave connected to a crankshaft and a driven sheave connected to a rear wheel axle, and is accommodated in a belt chamber by a V belt. This V-belt transmission is provided on one of the left and right sides of the rear wheel, and an exhaust muffler is mounted on the opposite side.

FIG. 6 is an external view of a conventional V-belt transmission. The V-belt transmission 50 is provided on the left side surface of the rear wheel (not shown). A V-belt transmission mechanism (not shown) connected to a crankshaft (not shown) slightly ahead of the kick shaft 52 is accommodated in the belt chamber 51. A front cover 53 is attached to the front portion of the belt chamber 51, and a suction port 54 for taking in outside air is provided at the front end portion of the front cover 53. The outside air introduced from the suction port 54 as shown by the arrow A is supplied to the front cover 5
3 flows into the belt chamber 51 through an opening (not shown) provided on the back side of the belt 3. The inflowing outside air circulates in the belt chamber 51 and is exhausted to the outside as indicated by arrows B and C through exhaust ports (not shown) formed on the rear surface and the lower surface side. In this manner, the outside air taken in from the front of the belt chamber was used to ventilate and cool the belt chamber.

[0004]

However, in the conventional belt transmission cooling structure, the intake port and the exhaust port for the outside air are provided at low positions in the belt chamber.
For example, when traveling in the rain or the like, water may enter the belt chamber through the inlet and the outlet, especially in a water pool, which causes deterioration of the belt and the speed change mechanism.

The present invention has been made in view of the above prior art, and an object of the present invention is to provide a cooling structure for a belt transmission of a motorcycle, which prevents water from entering a belt chamber from a deep water pool or the like.

[0006]

In order to achieve the above object, according to the present invention, a drive sheave connected to a power source and a driven sheave connected to an axle are wound around a V-belt and housed in a belt chamber. In a cooling structure of a belt transmission of a motorcycle, wherein the belt chamber is provided with an inlet and an outlet for outside air, and the outside air for cooling is circulated through the inlet and the outlet into the belt chamber. The exit is
A cooling structure for a belt transmission, characterized in that the cooling structure is formed on the front side and the rear side of the belt chamber, respectively.

According to this structure, the inlet for taking in the cooling air and the outlet for exhausting the outside air flowing through the belt chamber are both provided in the upper part of the belt chamber, so that water from the lower side of the vehicle body such as a water pool is collected. It is difficult to get into the belt chamber,
The deterioration of the belt and the speed change mechanism is suppressed.

A preferred configuration example is characterized in that an upper cover for partitioning the inlet and outlet of the upper part of the belt chamber to cover them is provided.

According to this structure, the intake port and the exhaust port for the outside air, which are open to the upper surface side of the belt chamber, are partitioned and separated from each other on the upper side of the belt chamber, and the upper surface side is covered with the upper cover. Water is prevented from entering the belt chamber from the upper side of the machine through the suction port and the discharge port. In addition, this upper cover can be used as a foot-holding step when a tandem rider boards, and usability is improved.

In a further preferred configuration example, an outside air introduction passage communicating with the suction port is provided, and an outside air intake of the outside air introduction passage is opened at a position higher than the belt chamber upper surface in front of the belt chamber, and the outside air introduction passage is opened. Is characterized in that it is divided in the middle to provide a void.

According to this structure, since the outside air introduction passage having the outside air intake port opened at a position higher than the upper surface of the belt chamber is connected to the belt chamber, intrusion of water from below into the belt chamber is effectively prevented. To be done. Further, by providing a gap by dividing the outside air introduction passage in the middle, water mixed in the outside air can be separated before flowing into the belt chamber and flowed out from this gap. As a result, it is possible to more reliably prevent water from entering the belt chamber.

In a further preferred configuration example, a filter unit is attached to the outside air introduction passage on the downstream side of the gap, and the filter unit is pressed and held by the upper cover via an elastic material.

According to this structure, after water is separated and dropped in the gap of the outside air introduction passage, dust and foreign matters are removed by the outside air passing through the filter, so that the V belt in the belt chamber and the gear shift due to the dust and foreign matters. The deterioration of the mechanism is prevented.
Further, the filter unit incorporating the filter can be compactly arranged through the elastic material by the upper cover, and the rattling of the filter unit can be suppressed and the filter unit can be securely fixed and held.

In a further preferred configuration example, the upper cover on the discharge port side is provided at intervals between the upper surface side, the side surface side and the rear surface side of the belt chamber.

According to this structure, since the upper cover covers the periphery of the discharge port on the upper surface side, the side surface side and the rear surface side with a space, the outside air flowing through the belt chamber flows out from the belt chamber smoothly and is discharged. To be done. This enhances the cooling effect.

In a further preferred configuration example, a rib is provided in the gap between the upper cover and the belt chamber on the front side of the discharge port.

According to this structure, the ribs provided on the exhaust passage can prevent external water from flowing back into the belt chamber through the gap between the upper cover and the belt chamber. Furthermore, since the upper cover is fixed on the belt chamber via the ribs provided on the belt chamber cover, the strength of the belt chamber cover itself and the assembling strength are enhanced.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a vehicle body rear portion of a motorcycle to which the present invention is applied. The rear part of the vehicle body of the motorcycle includes a seat 1, a rear wheel 2, and a swing unit engine 4 mounted on a vehicle body frame 3. A link 6 is attached to the vehicle body frame 3 via a first pivot 5. The link 6 is pivotally attached to an engine bracket 8 which is integral with a crankcase (not shown) of the swing unit engine 4 via a second pivot 7. The swing unit engine 4 is swingably attached to the vehicle body through the first and second pivots 5 and 7 and a shock absorber (not shown).

A side stand 9 for supporting the vehicle body when the vehicle body is stopped is provided below the swing unit engine 4, and a main stand 10 is provided behind it. A kick pedal 11 for starting the engine is attached to a side surface of the swing unit engine 4 via a kick shaft 12. A protector 13 for guarding the swing unit engine 4 and a heel of the tandem rider is provided in front of the kick shaft 12, and a tandem rider footrest 14 is provided in front of the protector 13.

The swing unit engine 4 is provided with a V-belt type transmission, which will be described later, and an intake port 15 for taking in the outside air for cooling the transmission and an outside air duct 16 are provided in the upper front part. The V-belt type transmission is covered with a belt chamber cover 17, and an upper part is covered with an upper cover 18. Top cover 18
Is further covered with a makeup cover 19.

FIG. 2 is a sectional view of a swing unit engine to which the present invention is applied, as seen from above. The swing unit engine 4 includes a belt chamber cover 17 and a crankcase 2.
It is formed by aligning 0 on the mating surface P. Inside, the engine 21 is stored in the center front, the belt chamber 22 is on the left side, and the gear mechanism 35 is on the rear side.
Connected to 3.

The engine 21 has intake / exhaust valves (not shown).
Cam shaft 23 for opening and closing, spark plug 24, piston 2
5, a connecting rod 26 that connects the piston 25 and the crankshaft 27, and the like. The crankshaft 27 is the belt chamber 22.
The drive sheave 28 is attached. The drive sheave 28 is bridged by a V belt 30 to a driven sheave 31 mounted on a driven shaft 32. Rear wheel 2 is axle 3
3 and the tire 34. Both the driving sheave 28 and the driven sheave 31 are composed of a pair of V-shaped sheave members that face each other. One of the facing sheave members is axially movable, and the facing width of the V-shape is changed to change the facing width of each sheave. The speed is changed by changing the engagement depth of the V belt 30 with respect to the V groove.

Fins 29a are provided on the rear surface of the sheave body on the outer surface side of the drive sheave 28 to form a suction fan 29. The rotation of the drive sheave 28 causes the suction fan 29 to rotate, and the belt chamber cover 1 formed at a position facing the rotation of the suction fan 29.
Outside air is sucked into the belt chamber 22 through the filter (not shown) from the opening 7 as described later.

FIG. 3 is a schematic view of the cooling structure of the belt transmission according to the present invention as seen from above, and FIG. 4 is a schematic view of the cooling structure of the belt transmission of the present invention as seen from the side. 5 is a sectional view taken along line AA of FIG.

The belt transmission according to the present invention has a side surface covered with a belt chamber cover 17, an upper surface covered with an upper cover 18, and an upper surface covered with a decorative cover 19. The belt chamber cover 17 and the upper cover 18 are made of, for example, aluminum die casting, and are plated. The decorative cover 19 is made of resin, and prevents the plating of the upper cover 18 from being peeled off when the tandem rider rides on the upper cover 18 with his / her feet.
The upper cover 18 covers the belt chamber cover 17 in a state where the rear portion (exhaust portion) covered with the decorative cover 19 and the front portion (intake portion) on the front side thereof are partitioned and disconnected. The rear portion covers the upper side of the outlet 17 with a gap between the upper surface, the rear surface, and the side surface with respect to the upper portion of the belt chamber cover 17.

The outside air duct 16 is connected to the front end of the front portion. The outside air duct 16 is bent at a plurality of positions, and the suction port 15 for introducing outside air is formed at the tip. This suction port 15
Open upward at a position in front of the belt chamber and above the upper surface of the belt chamber. A plurality of drain holes 48 are formed along the flow path on the lower surface side of the outside air duct 16. When rainwater or the like enters through the suction port 15, water flows out through the drain hole 48.

The connecting portion 36 between the outside air duct 16 and the upper cover 18 is connected with a gap 37 formed around the end of the duct. A sponge material (not shown) is mounted in the void 37. The connecting portion 36 divides the outside air introduction passage 47 (shown by a white arrow) formed in the outside air duct 16 and the upper cover 18 communicating with the outside air duct 16 to form a gap 37, so that the gap 37 is formed. Water that is mixed and flowing into the outside air is separated and prevented from entering the upper cover 18. The water mixed in the outside air hits the side wall of the bending outside air duct 16 and efficiently separates and flows on the lower surface of the duct, flows out from the water drain hole 48, and the water which cannot be completely removed is separated by the connection portion 36. It is prevented from being separated and entering the upper cover 18.

The flow of outside air on the intake side is as follows. By the action of the suction fan 29 (FIG. 2) in the belt chamber, the outside air is taken in through the suction port 15, flows through the outside air duct 16 as indicated by arrow A, and passes through the connecting portion 36.
After that, from the lower side of the filter unit 40, it passes through the filter element 39 as indicated by an arrow B and flows inside the filter case 38 as indicated by an arrow C. After that, as shown by an arrow D, it flows downward in the upper case 18, and passes through the second filter element 44 from the opening (not shown) provided at the position of the drive sheave 28 (FIG. 2) described above and the belt chamber 22 (FIG. ) Is sucked in.

The outside air which has circulated in the belt chamber and cooled in the belt chamber is exhausted from the exhaust port 45 at the upper rear portion of the belt chamber. At this time, as described above, the periphery of the exhaust port 45 is covered by the upper cover 18 with a gap between the upper surface, the side surface, and the rear surface, so that the exhaust gas smoothly flows forward and backward without generating air resistance. The exhaust gas that has flowed rearward from the exhaust port 45 is discharged downward in the rear part as indicated by arrow E. Exhaust that flows forward is arrow F
It is discharged from the side of the belt chamber cover 17 as described above.

On the upper surface and the side surface of the belt chamber cover 17, a standing wall rib 46 and a fin rib 49 are formed in a gap between the belt cover 17 and the upper cover 18, respectively. Exhaust gas flows as shown by an arrow F through the standing wall ribs 46 and the fin ribs 49. By forming the standing wall-shaped ribs 46 and the fin-shaped ribs 49 in the gap between the upper cover 18 and the belt chamber cover 17, water flows backward from the outside through the gap between the covers and inside the discharge port 45. Is prevented from entering.

A filter case 38 is provided behind the connecting portion 36.
And filter unit 39 comprising filter element 39
0, and two elastic ridges 41 are mounted on the filter unit 40. A bracket 42 is integrally formed on the lower surface side of the filter case 38. This bracket 4
The filter unit 40 is mounted in the upper cover 18 by hooking 2 to the pins 43 provided on the inner surface of the upper cover 18 to support the pin 43. At this time, rattling of the filter unit 40 can be suppressed by the upper cover 18 pressing the filter unit 40 via the elastic protrusion 41 on the upper surface of the filter case 38.

[0032]

As described above, in the present invention, both the inlet for taking in the cooling outside air and the outlet for exhausting the outside air circulating in the belt chamber are provided in the upper part of the belt chamber, so that water pools and the like are not formed. Water from the lower side of the vehicle body does not easily enter the belt chamber, and deterioration of the belt and the speed change mechanism is suppressed.

[Brief description of drawings]

FIG. 1 is a side view of a vehicle body rear portion of a motorcycle to which the present invention is applied.

FIG. 2 is a sectional view of a swing unit engine to which the present invention is applied, as seen from above.

FIG. 3 is a schematic view of the cooling structure of the belt transmission according to the present invention as viewed from above.

FIG. 4 is a schematic view of a cooling structure for a belt transmission according to the present invention as seen from a side surface.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is an external view of a conventional V-belt transmission.

[Explanation of symbols]

1: Seat, 2: Rear wheel, 3: Body frame, 4: Swing unit engine, 5: First pivot, 6: Link,
7: Second pivot, 8: Engine bracket, 9: Side stand, 10: Main stand, 11: Kick pedal, 12: Kick shaft, 13: Protector, 14: Footrest for tandem rider, 15: Intake port, 16: Outside air duct , 17: Belt chamber cover, 18: Top cover, 1
9: cosmetic cover, 20: crankcase, 21: engine, 22: belt chamber, 23: cam shaft, 24: spark plug, 25: piston, 26: connecting rod, 27: crankshaft, 28: drive sheave, 29: suction Fan, 29a:
Fins, 30: V belt, 31: Driven sheave, 32:
Driven shaft, 33: axle, 34: tire, 35: gear mechanism, 36: connection part, 37: air gap, 38: filter case, 39: filter element, 40: filter unit, 41: elastic ridge, 42: bracket , 43: pin,
44: second filter element, 45: discharge port, 46:
Standing wall ribs, 47: outside air introduction passage, 48: drainage hole, 4
9: fin-shaped ribs, 50: V-belt transmission, 51: belt chamber, 52: kick shaft, 53: front cover, 54: suction port.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J050 AA02 BA03 BB08 CA02 CE03                       CE06 DA03                 3J063 AA06 AB22 AC03 BB02 CA01                       CD45 XH04 XH13 XH22 XH42

Claims (6)

[Claims] 1. A drive sheave connected to a power source and a driven sheave connected to an axle are wound around a V-belt and accommodated in a belt chamber, and the belt chamber is provided with an intake port and an exhaust port for outside air, In a cooling structure for a belt transmission of a motorcycle, wherein the outside air for cooling is circulated into the belt chamber through the inlet port and the outlet port, the inlet port and the outlet port for the outside air are provided on the front side and the rear side of the belt chamber, respectively. A cooling structure for a belt transmission characterized by being formed. 2. The cooling structure for a belt transmission according to claim 1, further comprising an upper cover for partitioning an inlet and an outlet at an upper portion of the belt chamber to cover them. 3. An outside air introduction passage communicating with the intake port is provided, and an outside air intake port of the outside air introduction passage is opened at a position higher than the upper surface of the belt chamber in front of the belt chamber, and the outside air introduction passage is divided halfway. The cooling structure for a belt transmission according to claim 1 or 2, wherein a gap is provided. 4. The belt shift according to claim 3, wherein a filter unit is attached to the outside air introduction passage on the downstream side of the gap, and the filter unit is pressed and held by the upper cover via an elastic material. Machine cooling structure. 5. The discharge side upper cover is provided with a gap between the upper surface side, the side surface side and the rear surface side of the belt chamber. The cooling structure for the belt transmission described in. 6. The cooling structure for a belt transmission according to claim 5, wherein a rib is provided in a gap between the upper cover and the belt chamber on the front side of the discharge port.