JP2019158080A - Belt type continuously variable transmission device for saddle-riding type vehicle - Google Patents

Abstract

[Problem] A belt-type continuously variable transmission for a straddle-type vehicle that has a simple structure and increases cooling air blowing efficiency without increasing the size of the transmission case and transmission case cover. [Solution] A belt-type continuously variable transmission 40 includes a belt 45 between a driving pulley 41 and a driven pulley 47 provided with a cooling fan 44; a transmission case 30 extending rearward from an internal combustion engine E; , a transmission case cover 60 which constitutes a belt chamber 55 for accommodating a belt-type continuously variable transmission between the transmission case and a cooling air inlet 61 facing a cooling fan; An air guide duct cover 80 that covers the front side including the cooling air inlet and is provided with an outside air intake 81; and an inner duct member 70 that is sandwiched between the cooling air inlet and the air guide duct cover and is provided with a cooling air inflow hole 71. The air guide duct cover has arc-shaped air guide ribs 85, 86 that protrude toward the inner duct member and surround the central axis X of the cooling fan, and the air guide ribs form an arc-shaped air guide passage 95. A defined belt-type continuously variable transmission. [Selection diagram] Figure 4

Description

  The present invention relates to a belt type continuously variable transmission for a straddle-type vehicle.

In order to improve the cooling air blowing efficiency for belt type continuously variable transmissions, the pressure booster is formed on the casing of the belt type continuously variable transmission so that the gap between the cooling fan and the fan blades becomes wider toward the downstream side. For example, Patent Document 1 below shows a passage formed and a discharge port formed at the downstream end of the pressure increasing passage.
However, in what is shown in the following Patent Document 1, since the pressure increasing passage is provided in order to improve the blowing efficiency, the casing is formed so that the gap between the casing and the blowing blade becomes wider toward the downstream side in the rotation direction of the cooling fan. Therefore, the casing is enlarged on the downstream side in the rotational direction of the blower blades.

JP 2004-204988 A (FIGS. 1 to 4)

  The present invention has been made in view of the above-described prior art, and it is possible to increase the cooling air blowing efficiency with a simple structure without increasing the size of the transmission case and the transmission case cover that accommodate the belt-type continuously variable transmission. It is an object of the present invention to provide a belt type continuously variable transmission for a straddle-type vehicle that can be enhanced.

In order to solve the above problems, the present invention provides:
In a belt-type continuously variable transmission that is mounted on a straddle-type vehicle and that shifts power transmitted from an internal combustion engine and transmits the power to drive wheels.
A driving pulley having a driving force transmitted from a crankshaft of the internal combustion engine and provided with a cooling fan toward a side of the vehicle; a driven pulley for transmitting power to the driving wheel of the saddle riding type vehicle; the driving pulley; Covers a belt-type continuously variable transmission having a belt spanned between driven pulleys, a transmission case integrally extended rearward from the internal combustion engine, and an outer side in the vehicle width direction of the transmission case. A belt chamber for housing the belt-type continuously variable transmission is formed between the transmission case and a cooling air introduction port for introducing cooling air into the belt chamber opens to a front portion facing the cooling fan; The formed transmission case cover, and at least the front portion including the cooling air inlet of the transmission case cover from the outside in the vehicle width direction, including an outside air inlet and guiding the outside air to the cooling air inlet Daku Comprising a cover and an inner duct member having a sandwiched cooling air inlet between said air guide duct cover and the cooling air inlet,
The wind guide duct cover has an arc-shaped wind guide rib that protrudes toward the inner duct member and surrounds the central axis of the cooling fan, and between the wind guide duct cover and the inner duct member, A belt type continuously variable transmission for a saddle riding type vehicle, characterized in that an arcuate wind guide passage is defined by a wind guide rib.

According to the configuration of the above invention,
Without increasing the size of the transmission case and transmission case cover that accommodates the belt-type continuously variable transmission, the arc-shaped air guide ribs generate a swirling flow in the cooling air to increase the flow velocity of the cooling air and send it into the belt chamber The air blowing efficiency can be increased with a simple structure.

In the above configuration,
The cooling air inflow hole of the inner duct member is provided so as to face the cooling air introduction port, and the projecting end of the air guide rib surrounds the outer periphery of the cooling air inflow hole leaving a part of the gap. You may position so.
According to its configuration,
The cooling air inflow hole is provided so as to face the cooling air introduction port, and the cooling air flows into the cooling air inflow hole from the gap portion of the air guide rib, so that the flow velocity of the cooling air is increased and the belt type continuously variable transmission is installed. Cooling air can be taken in, and ventilation efficiency and cooling efficiency can be improved.

In the above configuration,
The arc-shaped air guide passage may be defined as a spiral air guide passage from the outside air inlet to the cooling air inflow hole by the air guide rib.
According to its configuration,
Since the cooling air passes through the spiral air guide passage from the outside air inlet to the cooling air inflow hole, the flow velocity is efficiently increased and flows into the cooling air inflow hole, so that the air blowing efficiency and the cooling efficiency are further increased. Can do.

In the above configuration,
The arc-shaped air guide rib may be provided with a discharge hole penetrating from the air guide passage in the radius of curvature direction.
According to its configuration,
Since the discharge holes are provided in the arc-shaped air guide ribs that form the outer peripheral surface of the arc-shaped air guide passage where the flow velocity is high, dust and foreign matters in the cooling air can be discharged from the discharge holes by centrifugal force. It is possible to suppress dust and foreign matter from entering the step transmission.

In the above configuration,
The outside air inlet may be provided above the cooling air inlet.
According to its configuration,
Since the outside air inlet is provided above the cooling air inlet, the length of the air guide passage that generates the swirling flow in the cooling air can be shortened, and the swirling flow can be generated in the cooling air with a smaller structure. Can be made easier.

The present invention also provides a driving pulley in which driving force is transmitted from a crankshaft of an internal combustion engine mounted on a saddle riding type vehicle and a cooling fan is provided toward the side of the vehicle, and the driving wheels of the saddle riding type vehicle are powered. A driven pulley that transmits the transmission, a transmission case that houses a belt spanned between the driving pulley and the driven pulley, and a transmission case cover that is fitted to the transmission case,
Belt-type continuously variable for saddle riding type vehicle provided with an outside air inlet, a cooling air inlet for taking cooling air into the transmission case, and a wind guide path between the outside air inlet and the cooling air inlet In the transmission,
The wind guide path (95, 195) is a belt type continuously variable transmission for a saddle riding type vehicle, characterized in that it is formed in an arc shape.

According to the configuration of the above invention,
Without increasing the size of the transmission case and transmission case cover that accommodates the belt-type continuously variable transmission, a swirl flow is generated in the cooling air by the arc-shaped air guide passage, and the flow velocity of the cooling air is increased and sent into the belt chamber. The air blowing efficiency can be increased with a simple structure. There is an effect.

According to the belt type continuously variable transmission of the saddle riding type vehicle of the present invention,
Without increasing the size of the transmission case and transmission case cover that accommodate the belt-type continuously variable transmission, a swirling flow is generated in the cooling air by the arc-shaped air guide ribs or the arc-shaped air guide passage, and the flow speed of the cooling air is reduced. It can be raised and fed into the belt chamber, and the air blowing efficiency can be increased with a simple structure.

1 is a schematic left side view of a motorcycle according to Embodiment 1 of the present invention. It is a left view of the belt type continuously variable transmission of the power unit in FIG. FIG. 3 is a rear cross-sectional view of the belt-type continuously variable transmission, taken along the line III-III in FIG. It is a left view of the transmission case cover in the state where the air duct cover is attached to the front. FIG. 5 is a cross-sectional plan view of the belt type continuously variable transmission as viewed in the direction of arrows VV in FIGS. 2 and 4. It is a left view of the inner side duct member in Embodiment 1. It is a right view of an air guide duct cover, and shows the inner surface of an air guide duct cover. It is the perspective view which looked at the inner surface of the wind guide duct cover of FIG. It is a left view of the inner side duct member in Embodiment 2. It is a right view of the wind guide duct cover of Embodiment 2, and shows the inner surface of a wind guide duct cover. It is the perspective view which looked at the inner surface of the wind guide duct cover of FIG.

A belt type continuously variable transmission for a straddle-type vehicle according to Embodiment 1 of the present invention will be described with reference to FIGS.
Note that the directions such as front, rear, left, right, up and down in the description and claims of the present specification are in accordance with the direction of the saddle riding type vehicle according to the present embodiment. In the present embodiment, the saddle riding type vehicle is specifically a scooter type motorcycle (hereinafter simply referred to as “motorcycle”).
In the figure, an arrow FR indicates the front of the straddle-type vehicle according to the present embodiment, LH indicates the left side of the vehicle, RH indicates the right side of the vehicle, and UP indicates the upper side of the vehicle.
Moreover, the small arrow written on each apparatus and member shows the flow direction of cooling air typically.

1 to 8 relate to Embodiment 1 of the present invention, and FIG. 1 shows an outline of a left side surface of a motorcycle 1 according to this embodiment. FIG. 2 is a left side view of the belt type continuously variable transmission T of the power unit P in FIG.
In the motorcycle 1 of the first embodiment, the vehicle body front portion 1f and the vehicle body rear portion 1r are connected via a low floor portion 1c, and the vehicle body frame forming the skeleton of the vehicle body is generally composed of the down tube 3 and the main pipe. It consists of four. That is, the down tube 3 extends downward from the head pipe 2 of the vehicle body front portion 1f, the down tube 3 is bent horizontally at the lower end and extends rearward below the floor portion 1c, and a pair of left and right main pipes 4 are formed at the rear end. Connected, the main pipe 4 rises upward from the connecting portion, bends, and extends obliquely rearward.

  A seat 5 is disposed above the main pipe 4. On the other hand, at the front part 1f of the vehicle body, a handle 6 is provided on the upper side and is pivotally supported by the head pipe 2. A front fork 7 extends downward and a front wheel 8 is pivotally supported at the lower end thereof. The motorcycle 1 is mounted with a power unit P supported by a main pipe 4.

  A main stand 18 is provided below the power unit P so as to be raised and lowered. When the leg portion 18a is laid down in the retracted state, the operating arm 18b extending leftward from the left leg portion 18a is disposed in front of and behind the transmission case cover 60 that covers a belt type continuously variable transmission T described later from the left. The rear position of the center of the direction is curved from the lower surface along the left side surface and extends upward, and the footrest plate 18c at the tip reaches the upper edge of the transmission case cover 60.

  The power unit P is configured by a belt-type continuously variable transmission T extending integrally from the front internal combustion engine E to the rear. The internal combustion engine E is a single-cylinder four-stroke internal combustion engine, and a cylinder block 22, a cylinder head 23, and a cylinder head cover 24 project forward from a crankcase 21 that supports the crankshaft 20 in the vehicle width direction and is substantially horizontal. It leans forward greatly to a state close to.

  A pair of left and right support brackets 12, 12 extend downward from the lower end of the crankcase 21. Hanger arms 12 h, 12 h protrude forward from the support brackets 12, 12, and the hanger arm 12 h is connected to the main pipe 4. The power unit P is connected and supported so as to be swingable with respect to the vehicle body through a bracket 10 and a link member 11 projecting rearward from the front lower portion.

A belt type continuously variable transmission T extending rearwardly from the internal combustion engine E in the power unit P is provided with rear wheels (drive wheels in the present invention) on the rear axle 14 which is an output shaft of a reduction gear mechanism Tr provided at the rear part thereof. ]) 15 is provided (see FIG. 2).
A rear cushion 17 is interposed between the support bracket 16 erected at the rear end of the belt type continuously variable transmission T and the rear portion of the main pipe 4 (see FIG. 1).

  An intake pipe 25 extends from the upper part of the cylinder head 23 which is largely inclined forward of the internal combustion engine E, curves backward, and reaches an air cleaner 27 above the belt type continuously variable transmission T via a throttle body 26. On the other hand, the exhaust pipe 28 extending downward from the lower part of the cylinder head 23 is bent rearward, is biased to the right and extends rearward, and is connected to the muffler 29 on the right side of the rear wheel 15.

  As shown in FIG. 3 which shows a rear cross section of the belt type continuously variable transmission T as viewed in the direction of arrows III-III in FIG. 2, the crankcase 21 which supports the crankshaft 20 in the vehicle width direction is a right crank. The case 21R and the front portion 30a of the long transmission case 30 on the left and right sides are combined with the left and right (see FIG. 3).

The transmission case 30 includes a rear portion 30b extending rearward from the front portion 30a to the side of the rear wheel 15 (see FIG. 2). The rear part 30b of the transmission case 30 has a long oval shape extending forward and backward from the front part 30a and opened leftward. A transmission case cover 60 is put on the transmission case 30 from the left side, and a belt chamber 55 is formed therein. The belt-type continuously variable transmission 40 is accommodated in the belt chamber 55, and the belt-type continuously variable transmission T and It has become.
The power unit P is configured by integrating an internal combustion engine E and a belt type continuously variable transmission T.

As shown in FIG. 5, the front drive shaft of the belt-type continuously variable transmission 40 is the crankshaft 20, and the drive pulley is attached to the extension shaft portion of the crankshaft 20 protruding from the transmission case 30 into the belt chamber 55. 41 is provided.
The drive pulley 41 is pivotally supported at the extension shaft portion of the crankshaft 20 so as to be opposed to the right side of the fixed drive pulley half 41a and fitted to the left end so as to be slidable in the axial direction. The movable drive pulley half 41b.
The fixed drive pulley half 41a and the movable drive pulley half 41b have opposing tapered surfaces that face each other and sandwich the V-belt 45 therebetween.

A plurality of centrifugal weights 43 are provided between the curved back side (right side) of the movable drive pulley half 41b and the guide plate 42 that is pivotally supported by the extension shaft portion of the crankshaft 20 and fixed in contact with the journal portion. It is disposed so as to be movable in the radial direction.
Many blades of the cooling fan 44 are formed on the back surface (left surface) of the fixed drive pulley half 41a.
Therefore, the crankshaft 20 and the cooling fan 44 share the central axis X.

  The rear rear driven shaft corresponding to the front drive shaft (crankshaft 20) on which the drive pulley 41 is pivotally supported is the reduction gear input shaft 46 of the reduction gear mechanism Tr. A fixed driven pulley half 48a is fitted to an inner sleeve 47a that is rotatably supported by the speed reducer input shaft 46, and is externally supported to be axially movable relative to the inner sleeve 47a on the left side of the fixed driven pulley half 48a. The movable driven pulley half 48b is fitted to the outer sleeve 47b, and the driven pulley 48 is constituted by the two driven pulley halves 48a and 48b.

The movable driven pulley half 48b is biased by a spring 49 in a direction approaching the fixed driven pulley half 48a, and a torque cam is provided between the outer sleeve 47b and the inner sleeve 47a integral with the movable driven pulley half 48b. A mechanism 53 is incorporated.
A V-belt 45 is sandwiched between both driven pulley halves 48a and 48b.

  In the belt type continuously variable transmission 40, when the V-belt 45 is wound around the drive pulley 41 and the driven pulley 48 and the engine speed (the rotational speed of the crankshaft 20) changes, Since the weight 43 moves in the radial direction to move the movable drive pulley half 41b in the axial direction, and the groove width between the drive pulley halves 41a and 41b is changed, the drive pulley 41 of the V belt 45 is moved to. Then, the winding diameter of the driven pulley 48 is automatically changed via the endless V-belt 45 to change the speed.

A centrifugal clutch 50 is provided on the left side of the speed reducer input shaft 46 and the inner sleeve 47a.
In the centrifugal clutch 50, a clutch outer 52 that covers the outer periphery of the clutch inner 51 that is fitted to the inner sleeve 47a is fitted to the speed reducer input shaft 46, and the clutch inner 51 swings in the centrifugal direction against the spring 51b. A moving clutch shoe 51 s is provided to face the inner peripheral surface of the clutch outer 52.
Therefore, when the rotational speed of the power transmitted to the inner sleeve 47a via the V belt 45 increases, the clutch shoe 51s swings in the centrifugal direction against the spring 51b and moves to the inner peripheral surface of the clutch outer 52. Then, the centrifugal clutch 50 is engaged and transmitted to the speed reducer input shaft 46.

FIG. 4 is a left side view of the transmission case cover 60 with the air guide duct cover 80 attached to the front portion 60a.
FIG. 5 is a plan sectional view of the belt-type continuously variable transmission T as viewed in the direction of arrows VV in FIG. 4 (or FIG. 2).
4 and 5, the left side of the longitudinally long transmission case 30 is covered with a transmission case cover 60 and formed between the transmission case 30 and the transmission case cover 60. A belt type continuously variable transmission 40 and a centrifugal clutch 50 are accommodated in the belt chamber 55.

The transmission case cover 60 includes a case cover front portion 60a that covers the cooling fan 44 formed on the fixed drive pulley half 41a fitted to the left end of the crankshaft 20 that is a front drive shaft, and a rear driven shaft. The case cover rear portion 60b that covers the centrifugal clutch 50 provided at the left end of the speed reducer input shaft 46 from the left side, and the case cover center portion 60c that connects the case cover front portion 60a and the case cover rear portion 60b, It has a long oval shape.
The transmission case cover 60 is made of a metal aluminum alloy, and the surface thereof is painted.

The driving pulley 41 on the front side and the driven pulley 48 on the rear side are at the same position in the vehicle width direction since the V-belt 45 is bridged, and the centrifugal clutch 50 is positioned on the left side of the driven pulley 48 on the rear side.
Therefore, in the transmission case cover 60, a case cover rear portion 60b covering the centrifugal clutch 50 bulges outward in the vehicle width direction from a case cover front portion 60a covering the drive pulley 41 and the cooling fan 44.

A cooling air inlet 61 for introducing cooling air into the belt chamber 55 is formed in the case cover front portion 60a of the transmission case cover 60, and an annular convex rib 62 is formed around the cooling air inlet 61. ing.
Further, on the left side surface of the case cover front portion 60a, three cylindrical mounting boss portions 63 are formed around the large cooling air inlet 61 at the center so as to protrude to the left (outward direction of the vehicle width). .
Three cylindrical mounting bosses 63 are formed in front of the cooling air introduction port 61 and the other two are formed obliquely above and below the cooling air introduction port 61.
The cylindrical mounting boss 63 is formed with a screw hole.

A central cylindrical mounting boss portion 64 is formed on the case cover central portion 60c so as to protrude inward (right side) in the vehicle width direction (see FIG. 5).
Note that a plurality of mounting boss portions 65 for coupling the transmission case cover 60 to the transmission case 30 are formed on the outer peripheral edge of the transmission case cover 60 having an oval shape in a side view.

The case cover front portion 60a including the cooling air introduction port 61 of the transmission case cover 60 is covered with the air guide duct cover 80 with the inner duct member 70 interposed therebetween.
The inner duct member 70 and the air guide duct cover 80 are made of resin.

  As shown in FIG. 6, which is a left side view of the inner duct member 70, the inner duct member 70 includes a case cover facing portion 70 a that faces the case cover front portion 60 a of the transmission case cover 60 in a side view, and a case cover facing portion. The upper part of the part 70a is composed of an upper bulging part 70b bulging upward, and a cooling air inflow hole 71 is formed in the center of the case cover facing part 70a so as to face the cooling air inlet 61 of the transmission case cover 60. Yes.

On the right side surface of the case cover facing portion 70a of the inner duct member 70, an annular ring having a concave cross section around the cooling air inflow hole 71 facing the annular rim convex rib 62 on the transmission case cover 60 side. The rim concave rib 72 is formed (see FIG. 5).
A cylindrical mounting boss portion 73 into which the cylindrical mounting boss portion 63 fits in correspondence with the three cylindrical mounting boss portions 63 of the transmission case cover 60 is provided on the left side surface of the inner duct member 70 on the outer side in the vehicle width direction (left side). Is formed to protrude.
The end of the cylindrical mounting boss 73 has an annular bottom wall.

As shown in FIG. 6, the inner duct member 70 is continuously connected to the left side surface from the rear along the outer periphery of the cooling air inflow hole 71 of the case cover facing portion 70a so as to rotate clockwise in FIG. From the front, an arc-shaped central air guide concave rib 75 having a concave cross section extending continuously from the cooling air inflow hole 71 to the front of the upper bulging portion 70b surrounds the central axis X of the cooling fan 44. It is formed by protruding.
Further, it extends from the rear to the front along the upper edge of the upper bulging portion 70b, and rotates counterclockwise as shown in FIG. 6 while maintaining the required distance from the outer peripheral side of the central air guide concave rib 75. An arc-shaped outer peripheral air guide concave rib 76 having a concave cross section and joining the central air guide concave rib 75 above the cooling air inflow hole 71 surrounds the central axis X of the cooling fan 44. Are formed so as to protrude.

  Between the end of the central air guide concave rib 75 on the cooling air inflow hole 71 side and the central air guide concave rib 75 that goes around the cooling air inflow hole 71 and goes to the upper bulging portion 70b side, 75a is provided, and an outer peripheral gap 76a is provided between the end of the central air guide concave rib 75 on the upper bulging portion 70b side and the outer air guide concave rib 76.

  Therefore, it passes through the outer peripheral gap 76a from the upper bulging portion 70b, and turns between the outer peripheral air guide concave rib 76 and the central air guide concave rib 75 counterclockwise in FIG. 6, and passes through the central gap portion 75a. An arc-shaped air guide passage 95a on the inner duct member 70 side that reaches the cooling air inflow hole 71 is formed.

FIG. 7 is a right side view of the air guide duct cover 80 and shows the inner surface of the air guide duct cover 80. FIG. 8 is a perspective view of the inner surface of the air guide duct cover 80 of FIG. 7 as seen from the front.
Referring to FIG. 5, FIG. 7 and FIG. 8, the air guide duct cover 80 of the first embodiment is a case cover facing portion of the inner duct member 70 fitted in the case cover front portion 60 a of the transmission case cover 60. A duct cover main portion 80a facing the 70a and an outside air intake portion 80b facing the upper bulging portion 70b of the inner duct member 70 are formed.

Bolts are provided in the duct cover main portion 80a of the air guide duct cover 80 so as to be opposed to the three cylindrical mounting boss portions 73 protruding from the left side surface of the inner duct member 70 and recessed inward in the vehicle width direction (right side). A mounting cylindrical portion 83 that forms the recess 83a is formed to protrude.
The annular bottom wall at the end of the protruding mounting cylinder portion 83 abuts against the annular bottom wall of the opposing cylindrical mounting boss portion 73.
The annular bottom wall at the end of the mounting cylindrical portion 83 constitutes the bottom surface of the bolt insertion recess 83 a and serves as a fastening seat surface of the fastening bolt 91.

A central air guide concave rib 75 formed on the left side surface of the inner duct member 70 and an outer peripheral air guide concave rib are formed on the inner surface (right side surface) of the duct cover main portion 80a and the outside air intake portion 80b of the air guide duct cover 80. Opposing 76, a central air guide convex rib 85 and an outer peripheral air guide convex rib 86 are formed so as to project around the central axis X of the cooling fan 44.
Further, there is a central gap between the end of the central air guide convex rib 85 on the cooling air inflow hole 71 side and the central air guide convex rib 85 that travels around the cooling air inflow hole 71 and moves toward the outside air intake portion 80b. A side gap portion 85 a is provided, and an outer peripheral side gap 86 a is provided between the end of the central air guide convex rib 85 on the outside air intake portion 80 b side and the outer air guide convex rib 86.

In addition, a partition rib 84 is provided on the opposite side of the outer peripheral side gap 86a across the outside air intake port 81, that is, on the rear side of the outside air intake port 81 so as to prevent the outside air taken in from the rear side.
Therefore, it passes through the outer peripheral side gap 86a from the outside air inlet 81, rotates between the outer peripheral air guide convex rib 86 and the central air guide convex rib 85 clockwise in FIG. 7, and passes through the central side gap portion 85a. An arc-shaped air guide passage 95b on the air guide duct cover 80 side that reaches the cooling air inflow hole 71 is formed.

Therefore, when the air guide duct cover 80 is fitted to the outer surface of the inner duct member 70, the central air guide duct 80 has a central air guide concave rib 75 and an outer air guide concave rib 76. The convex rib 85 and the outer circumferential air guide convex rib 86 are fitted, and the air guide passage 95a on the inner duct member 70 side and the air guide passage 95b on the air duct cover 80 side are integrated with the arc-shaped air guide passage 95. Become.
As a result, as shown in FIG. 4, the air guide passage 95 is formed in a scroll shape from the outside air inlet 81 to the cooling air inflow hole 71.

  For this reason, the outside air taken in from the outside air inlet 81 turns up in the scroll-shaped air guide passage 95 to increase the speed, flows into the cooling air inflow hole 71, and rotates in synchronization with the crankshaft 20. Since the speed is further increased by the fan 44 and fed into the belt chamber 55, the belt type continuously variable transmission 40 in the belt chamber 55 can be effectively cooled.

In the present embodiment, the central gap portions 75a and 85a are provided in the first quadrant A around the central axis X of the cooling fan 44 shown in FIG. 7, but the first quadrant A, the second quadrant B, and the second quadrant shown in FIG. You may provide in any position of the 3rd quadrant C and the 4th quadrant D.
However, in the present embodiment shown in FIG. 7, the position of the illustrated first quadrant A is suitable.
In FIG. 7, the air guide passage 95b (95) is formed in the same way in the cross section of the flow path up to the central gap portion 85a, but even if the cross sectional area is changed, for example, the cross sectional area gradually decreases. Good. that is,
It does not matter whether it is due to the relationship between the central air guide convex rib 85 and the outer peripheral air guide convex rib 86 or the width of the air guide passage 95b in the vehicle width direction.

In addition, the outside air intake portion 80b of the air duct cover 80 is provided with an outside air inlet 81 that opens toward the rear, and the outside air inlet 81 is provided with a louver 82 that guides outside air and prevents foreign substances from entering. Thus, foreign matter flying from the front is difficult to enter from the outside air intake 81.
Further, when the outside air from the front enters the outside air intake portion 80b from the outside air inlet 81, it is reversed and passes forward through the outer peripheral side gap 86a. Therefore, foreign matter in the outside air is unlikely to enter the air guide passage 95 due to inertia. .
Further, the outer peripheral air guide convex rib 86 of the air guide duct cover 80 is provided with a discharge hole 86b for discharging a part of the cooling air in the vicinity of the lower end. Dust and other foreign matter in the cooling air flowing through the air guide passage 95 from the outside air inlet 81 are discharged from the discharge hole 86b by utilizing the fact that the centrifugal force causes the air to flow along the outer circumferential air guide convex rib 86. It has the same effect as a cyclone dust remover.

In order to assemble the transmission case cover 60, the inner duct member 70, and the air guide duct cover 80 to the transmission case 30, first, cover the transmission case 30 with the alignment surface of the periphery and cover the transmission case cover 60. The mounting boss portion 65 formed on the outer peripheral edge of the transmission case cover 60 is fastened to the transmission case 30 by the fastening bolt 90, and the transmission case cover 60 is attached to the transmission case 30.
Referring to FIG. 5, when the transmission case cover 60 is attached to the transmission case 30, the mounting boss protruding from the left side surface of the transmission case 30 facing the central cylindrical mounting boss portion 64 of the transmission case cover 60. The end surface of the central cylindrical mounting boss portion 64 on the transmission case cover 60 side contacts the end surface of the portion 31. A screw hole is formed in the end face of the mounting boss 31.
Therefore, the fastening bolt 92 is inserted into the central cylindrical mounting boss portion 64 of the transmission case cover 60 from the outside in the vehicle width direction, penetrates the central cylindrical mounting boss portion 64, and the screw hole of the mounting boss portion 31 of the transmission case 30 And the transmission case cover 60 is fastened to the transmission case 30.

The inner duct member 70 is superimposed on the case cover front side portion 60 a of the transmission case cover 60 attached to the transmission case 30 in this manner.
The three cylindrical mounting bosses 63 projecting from the case cover front portion 60a are positioned so as to fit into the cylindrical mounting bosses 73 of the inner duct member 70, and the inner duct member 70 is attached to the transmission case cover 60. When overlapped, the rim convex rib 62 of the transmission case cover 60 and the lip concave rib 72 of the inner duct member 70 are fitted via a seal member, and the cooling air inlet 61 of the transmission case cover 60 is fitted. The cooling air inflow hole 71 of the inner duct member 70 is located at the center of the inner duct member 70 and communicates therewith.

In this manner, the air guide duct cover 80 is covered from the side in a state where the inner duct member 70 is superimposed on the case cover front side portion 60a of the transmission case cover 60.
The central air guide convex rib 85 and the peripheral air guide convex rib 86 of the air guide duct cover 80 are fitted to the central air guide concave rib 75 and the outer air guide concave rib 76 of the inner duct member 70 with a seal member interposed therebetween. Then, the wind guide duct cover 80 is fitted to the transmission case cover 60, and the wind guide duct cover 80 is fitted to the inner duct member 70 and the transmission case cover 60.

As shown in FIG. 5, fastening bolts 91 are respectively inserted into the bolt insertion recesses 83a of the three mounting cylindrical portions 83 of the air guide duct cover 80 from the outside in the vehicle width direction, and the annular bottom wall of the mounting cylindrical portion 83 is Through the annular bottom wall of the cylindrical mounting boss 73 of the inner duct member 70 and screwed into the screw hole of the cylindrical mounting boss 63 of the transmission case cover 60, the inner duct member 70 and the transmission case cover 60 The air duct cover 80 is fastened.
In this way, together with the transmission case cover 60 that accommodates and covers the belt-type continuously variable transmission 40 inside the transmission case 30, the air duct guide cover 80 is attached with the inner duct member 70 interposed therebetween. .

  According to the belt type continuously variable transmission T of the first embodiment as described above, the cooling air introduction port 61 of the transmission case cover 60 is formed in the case cover front portion 60 so as to face the cooling fan 44. The cooling fan 44 formed on the back surface of the fixed drive pulley half 41a is rotated by the rotation of the crankshaft 20, so that the outside air is cooled by the outside air inlet 81 opened to the outside air intake portion 80b of the air guide duct cover 80. The cooling air thus taken in is the central air guide convex rib 85 and the outer air guide convex rib 86 of the air guide duct cover 80, and the central air guide concave rib 75 and the outer air guide of the inner duct member 70. Guided through the arc-shaped air guide passage 95 formed by fitting with the concave rib 76, it becomes a swirling flow to increase the flow velocity, and from the cooling air inlet 71 and the cooling air inlet 61 of the inner duct member 70, the belt chamber Introduced in 55, belt type stepless in the belt chamber 55 The speed machine 40 for cooling.

  Therefore, without increasing the size of the transmission case 30 and the transmission case cover 60 that accommodate the belt-type continuously variable transmission 40, the arc-shaped central wind guide convex rib 85 and the outer peripheral wind guide convex rib 86, or by them A swirling flow is generated in the cooling air by the formed arc-shaped air guide passage 95, the flow velocity of the cooling air can be increased and sent into the belt chamber 55, and the air blowing efficiency can be improved with a simple structure.

  Further, the cooling air inflow hole 71 of the inner duct member 70 is provided so as to face the cooling air introduction port 61, and the protruding end of the central air guide convex rib 85 has a part of the outer periphery of the cooling air inflow hole 71. It is positioned so as to leave the central gap 85a, and the cooling air is introduced from the central gap 85a of the central air guide convex rib 85 into the cooling air inflow hole 71. The cooling air can be taken into the continuously variable transmission 40, and the air blowing efficiency and the cooling efficiency can be improved.

  The arc-shaped air guide passage 95 is defined as a spiral air guide passage 95 from the outside air inlet 81 to the cooling air inflow hole by the central air guide convex rib 85 and the outer peripheral air guide convex rib 86. Therefore, when the cooling air passes through the spiral air guide passage 95, the flow velocity is efficiently increased and flows into the cooling air inflow hole 71. Therefore, ventilation efficiency and cooling efficiency can be further increased.

  Further, the arc-shaped outer peripheral air guide convex rib 86, which forms the outer peripheral surface of the arc-shaped air guide passage 95 with a high flow velocity, is provided with a discharge hole 86b penetrating from the air guide passage 95 in the curvature radius direction. Thus, dust and foreign matter in the cooling air can be discharged from the discharge hole 86 by centrifugal force, and entry of dust and foreign matter into the belt type continuously variable transmission 40 can be suppressed.

A belt type continuously variable transmission for a straddle-type vehicle according to a second embodiment of the present invention will be described with reference to FIGS. 9 to 11. The belt type continuously variable transmission T according to the second embodiment includes a wind guide duct cover 180. The central air guide convex rib 185 and the outer peripheral air guide convex rib 186, the central gap portion 185a and the outer peripheral gap portion 186a, and the central air guide concave rib 175 and the outer peripheral air guide concave shape of the inner duct member 170. The rib 176 and the center side gap 175a and the outer circumference side gap 176a have the same configuration except that they are different from the first embodiment.
Components having the same functions and arrangement as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted. Components having the same functions but different aspects or arrangements are different from those of the first embodiment. Differences from the first embodiment will be mainly described by attaching reference numerals in the 100s that are the same in two digits.
1 to 5 are also referred to in the second embodiment except for the above differences.

FIG. 9 is a left side view of the inner duct member 170 in the second embodiment. FIG. 10 is a right side view of the air guide duct cover 180 according to the second embodiment, and shows the inner surface of the air guide duct cover 180. FIG. 11 is a perspective view of the inner surface of the air guide duct cover 180 of FIG.
Referring to FIGS. 5 and 9 to 10, also in the air guide duct cover 180 of the second embodiment, the inner duct member 170 fitted in the case cover front part 60 a of the transmission case cover 60 faces the case cover. A duct cover main portion 80a facing the portion 70a and an outside air intake portion 80b facing the upper bulging portion 70b of the inner duct member 70 are formed.

Also in the second embodiment, the case cover front portion 60a including the cooling air inlet 61 of the transmission case cover 60 is covered with the air guide duct cover 180 from the outside with the inner duct member 170 interposed therebetween.
The inner duct member 170 and the air guide duct cover 180 are made of resin.

  As shown in FIG. 9, which is a left side view of the inner duct member 170, the inner duct member 170 includes a case cover facing portion 70 a that faces the case cover front portion 60 a of the transmission case cover 60 in a side view, and a case cover facing portion. The upper part of the part 70a is composed of an upper bulging part 70b bulging upward, and a cooling air inflow hole 71 is formed in the center of the case cover facing part 70a so as to face the cooling air inlet 61 of the transmission case cover 60. Yes.

On the right side surface of the case cover facing portion 70a of the inner duct member 170, an annular ring having a concave cross section around the cooling air inflow hole 71 facing the annular rim convex rib 62 on the transmission case cover 60 side. The rim concave rib 72 is formed (see FIG. 5).
On the left side surface of the inner duct member 170, similarly to the first embodiment, a cylindrical mounting boss portion 73 into which the cylindrical mounting boss portion 63 is fitted in correspondence with each of the three cylindrical mounting boss portions 63 of the transmission case cover 60 is provided. It is formed to protrude outward (left side) in the vehicle width direction.

9, the left side surface of the inner duct member 170 is continuous from the rear along the outer periphery of the cooling air inflow hole 71 of the case cover facing portion 70a so as to rotate clockwise in FIG. An arc-shaped central air guide concave rib 175 extending continuously to the upper end of the cooling air inflow hole 71 and having a concave cross section is formed so as to protrude so as to surround the central axis X of the cooling fan 44. .
Further, it extends from the rear to the front along the upper edge of the upper bulging portion 70b, and rotates counterclockwise as shown in FIG. 9 while maintaining a required distance from the outer peripheral side of the central air guide concave rib 175. The arc-shaped outer peripheral wind with a concave cross section that extends continuously to the upper end of the cooling air inflow hole 71 and bends upward and ends with a gap from the upper edge of the upper bulging portion 70b. A concave rib 176 is formed so as to project around the central axis X of the cooling fan 44.

A central gap 175a is formed between the start end and the end of the central air guide concave rib 175 around the cooling air inflow hole 71, and the peripheral air guide concave rib 176 on the upper edge of the upper bulging portion 70b, An outer peripheral gap 176a is formed between the end of the wind concave rib 176.
Therefore, it passes through the outer peripheral gap 176a from the upper bulging portion 70b, and rotates between the outer peripheral air guide concave rib 176 and the central air guide concave rib 175 in the counterclockwise direction of FIG. 9, and passes through the central gap 175a. An arc-shaped air guide passage 195a on the inner duct member 170 side that reaches the cooling air inflow hole 71 is formed.

  Also in the second embodiment, the air guide duct cover 180 includes a duct cover main portion 80a facing the case cover facing portion 70a of the inner duct member 170 fitted in the case cover front portion 60a of the transmission case cover 60, and an inner side. An outside air intake portion 80b facing the upward bulging portion 70b of the duct member 170 is formed.

  Bolts are provided in the duct cover main portion 80a of the air guide duct cover 180 so as to be recessed inward in the vehicle width direction (right side) so as to face the three cylindrical mounting boss portions 73 protruding from the left side surface of the inner duct member 170. A mounting cylindrical portion 83 that forms the recess 83a is formed to protrude in the same manner as in the first embodiment.

A central air guide concave rib 175 formed on the left side surface of the inner duct member 170 and an outer peripheral air guide concave rib are formed on the inner surface (right side surface) of the duct cover main portion 80a and the outside air intake portion 80b of the air guide duct cover 180. Opposing to 176, a central air guide convex rib 185 and an outer peripheral air guide convex rib 186 are formed so as to project around the central axis X of the cooling fan 44.
Further, a central gap 185a is formed between the start and end of the central air guide concave rib 185 around the cooling air inflow hole 71, and the outer air guide concave rib 186 at the upper edge of the outside air intake portion 80b, An outer peripheral side gap 186 a is formed between the end of the air guide concave rib 186.

In addition, a partition rib 184 is provided on the opposite side of the outer circumferential side gap 186a across the outside air intake port 81, that is, on the rear side of the outside air intake port 81 so as to prevent the outside air taken in from the rear side. -
Therefore, it passes through the outer peripheral side gap portion 186a from the outside air inlet 81, rotates between the outer peripheral air guide concave rib 186 and the central air guide concave rib 185 in the clockwise direction in FIG. 10, passes through the central side gap portion 185a, and is cooled. An arc-shaped air guide passage 195b on the inner duct member 180 side that reaches the wind inflow hole 71 is formed.

Therefore, when the air guide duct cover 180 is fitted to the outer surface of the inner duct member 170, the central air guide duct 180 has a central air guide concave rib 175 and an outer air guide concave rib 176. The convex rib 185 and the outer circumferential air guide convex rib 186 are fitted, and the air guide passage 195a on the inner duct member 170 side and the air guide passage 195b on the air duct cover 180 side are integrated with the arc-shaped air guide passage 195. Become.
As a result, the air guide passage 195 is formed in a circumferential circuit shape from the outside air inlet 81 to the cooling air inflow hole 71.

Therefore, the outside air taken in from the outside air inlet 81 is swung in the air guide passage 195 formed in a circumferential circuit shape, increases the speed, flows into the cooling air inflow hole 71, and rotates synchronously with the crankshaft 20. Since the speed is further increased by the cooling fan 44 and fed into the belt chamber 55, the belt-type continuously variable transmission 40 in the belt chamber 55 can be effectively cooled.
Therefore, also in the second embodiment, the arcuate central air guide convex rib 185 and the outer peripheral air guide convex shape without increasing the size of the transmission case 30 and the transmission case cover 60 that accommodate the belt type continuously variable transmission 40. The rib 186 or the arcuate air guide passage 195 formed by them can generate a swirling flow in the cooling air, increase the flow velocity of the cooling air and send it into the belt chamber 55, and improve the blowing efficiency with a simple structure. be able to.

In the present embodiment, the central gaps 175a and 185a are provided in the second quadrant B around the central axis X of the cooling fan 44 shown in FIG. 10, but the first quadrant A, the second quadrant B, the second quadrant B shown in FIG. You may provide in any position of the 3rd quadrant C and the 4th quadrant D.
However, in the present embodiment shown in FIG. 10, the position of the illustrated second quadrant B is suitable.
In FIG. 10, the air guide passage 195b (195) is formed in the same way in the cross section of the flow path up to the central gap 185a. However, even if the cross sectional area is changed, for example, the cross sectional area gradually decreases. Good. It does not matter whether it is due to the relationship between the central wind guide convex rib 185 and the outer wind guide convex rib 186 or the width of the wind guide passage 195b in the vehicle width direction.

Also in the second embodiment, the outside air intake portion 81 b of the air guide duct cover 180 has an outside air inlet 81 that opens toward the rear. The outside air inlet 81 guides outside air and allows foreign matter to enter. A louver 82 is provided to prevent foreign matter flying from the front from entering the outside air inlet 81.
When the outside air from the front enters the outside air intake portion 80b from the outside air inlet 81, it is reversed and passes forward through the outer peripheral side gap portion 186a, so that foreign matter in the outside air enters the air guide passage 195 due to inertia. hard.
Further, the outer circumferential air guide convex rib 186 of the air guide duct cover 180 is provided with a discharge hole 86b for discharging a part of the cooling air in the vicinity of the lower end. Dust and other foreign matter in the cooling air flowing from the outside air inlet 81 through the air guide passage 195 are discharged from the discharge hole 86b by utilizing the fact that it flows on the side along the outer peripheral air guide convex rib 186 by centrifugal force. It has the same effect as a cyclone dust remover.

  In addition, although the points different from the first embodiment in the second embodiment have been described above, the same effects as those in the first embodiment are obtained in the second embodiment with respect to the same configurations as those in the first embodiment.

As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to above-described embodiment, Various other changes are possible in the range of the summary of this invention. For example, the relationship between the rim convex rib 62 and the lip concave rib 72, the central air guide concave ribs 75 and 175, the outer peripheral air guide concave ribs 76 and 176, the central air guide convex ribs 85 and 185, the outer peripheral air guide In relation to the convex ribs 86 and 186, the irregularities may be reversed.
Further, the power unit and the internal combustion engine of the present invention are not limited to motorcycles, and may be widely applied to other types of saddle riding type vehicles.
For convenience of explanation, the left-right arrangement of the apparatus has been described along the illustrated embodiment. However, the arrangement is not limited thereto, and the left-right arrangement may be reversed.

  DESCRIPTION OF SYMBOLS 1 ... Motorcycle ("Saddle type vehicle" in this invention), 14 ... Rear axle, 15 ... Rear wheel ("Drive wheel" in this invention), 20 ... Crankshaft, 21 ... Crankcase, 21R ... Right crankcase , 30 ... Transmission case, 30a ... Front part, 30b ... Rear part, 40 ... Belt type continuously variable transmission, 41 ... Drive pulley, 44 ... Cooling fan, 45 ... V belt, 46 ... Reducer input shaft, 48 ... Driven Pulley, 55 ... Belt chamber, 60 ... Transmission case cover, 60a ... Case cover front, 61 ... Cooling air inlet, 62 ... Convex rib, 63 ... Cylindrical mounting boss, 70, 170 ... Inner duct member, 70a ... Case cover facing part, 70b ... Upward bulging part, 71 ... Cooling air inflow hole, 72 ... Ring edge concave rib, 73 ... Cylinder mounting boss part, 75,175 ... Central air guide concave rib, 75a, 175a ... Center side gap part , 76, 76 ... outer peripheral wind guide concave ribs, 76a, 176a ... outer peripheral gap, 80, 180 ... wind guide duct cover, 80a ... duct cover Main part, 80b ... Outside air intake part, 81 ... Outside air intake port, 83 ... Mounting cylindrical part, 85,185 ... Central wind guide convex rib ("wind guide rib" in the present invention), 85a, 185a ... Center side gap part, 86,186 ... outer peripheral wind guide convex rib ("wind guide rib" in the present invention), 86a, 186a ... outer peripheral side gap, 86b ... discharge hole, 95, 195 ... wind guide passage, P ... power unit, T ... belt type continuously variable transmission , E ... Internal combustion engine, X ... Crankshaft 20, central axis of cooling fan 44

Claims (6)

In a belt-type continuously variable transmission (T) mounted on a straddle-type vehicle (1), which shifts power transmitted from an internal combustion engine (E) and transmits it to drive wheels (15).
A driving pulley (41) in which a driving force is transmitted from a crankshaft (20) of the internal combustion engine (E) and a cooling fan (44) is provided toward the side of the vehicle, and the driving of the saddle riding type vehicle (1) A belt type continuously variable transmission comprising a driven pulley (47) for transmitting power to the wheel (15), and a belt (45) stretched between the drive pulley (41) and the driven pulley (47) ( 40)
A transmission case (30) integrally extended rearward from the internal combustion engine (E);
A belt chamber (55) that covers the outer side in the vehicle width direction of the transmission case (30) and accommodates the belt-type continuously variable transmission (40) between the transmission case (30) and the cooling case A transmission case cover (60) in which a cooling air introduction port (61) for introducing wind into the belt chamber (55) is formed in the front portion so as to face the cooling fan (44),
The transmission case cover (60) includes at least a front portion including the cooling air introduction port (61) from the outside in the vehicle width direction, and includes an outside air intake (81) and air is supplied to the cooling air introduction port (61). A guiding duct cover (80, 180) to guide,
An inner duct member (70, 170) having a cooling air inflow hole (71) sandwiched between the cooling air inlet (61) and the air guide duct cover (80, 180),
The air guide duct cover (80, 180) projects toward the inner duct member (70, 170) and has an arcuate air guide rib (85, 86) surrounding the central axis (X) of the cooling fan (44). 185,186)
Between the air duct cover (80, 180) and the inner duct member (70, 170), an arc-shaped air duct (95, 195) is defined by the air guide rib (85, 86, 185, 186). A belt type continuously variable transmission for a straddle-type vehicle.   The cooling air inflow hole (71) of the inner duct member (70) is provided to face the cooling air introduction port (61), and the projecting end of the air guide rib (85, 185) 2. A belt type continuously variable transmission for a saddle riding type vehicle according to claim 1, wherein the outer periphery of the wind inlet hole (71) is positioned so as to surround a part of the gaps (85a, 185a).   The arc-shaped air guide passage (95) is formed into a spiral air guide passage (95) from the outside air inlet (81) to the cooling air inlet hole (71) by the air guide ribs (85, 86). The belt type continuously variable transmission for a saddle type vehicle according to claim 2, wherein the belt type continuously variable transmission is defined.   The discharge holes (86b) penetrating in the radial direction of curvature from the air guide passages (95, 195) are provided in the arc-shaped air guide ribs (86, 186). A belt type continuously variable transmission for a saddle riding type vehicle according to any one of claims 3 to 4.   The belt for straddle-type vehicles according to any one of claims 1 to 4, wherein the outside air inlet (81) is provided above the cooling air inlet (61). Type continuously variable transmission. A driving pulley (41) in which driving force is transmitted from a crankshaft (20) of an internal combustion engine (E) mounted on the saddle riding type vehicle (1) and a cooling fan (44) is provided toward the side of the vehicle; Accommodates a driven pulley (47) that transmits power to the drive wheels (15) of the saddle riding type vehicle (1), and a belt (45) spanned between the drive pulley (41) and the driven pulley (47). A transmission case (30), and a transmission case cover (60) adapted to the transmission case (30),
An outside air inlet (81), a cooling air inlet (61) for taking cooling air into the transmission case (30), and a guide between the outside air inlet (81) and the cooling air inlet (61). In a belt type continuously variable transmission (T) of a saddle riding type vehicle provided with a wind passage (95, 195),
The belt type continuously variable transmission for a saddle riding type vehicle, wherein the air guide passages (95, 195) are formed in an arc shape.

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