JP6771922B2 - Power unit for saddle-mounted vehicles with kick starter - Google Patents

Description

The present invention relates to a power unit for a saddle-type vehicle provided with a kick start device.

As a power unit for a saddle-mounted vehicle equipped with a conventional kick starter, a belt-type continuously variable transmission is provided between a transmission case connected to the engine body of an internal combustion engine and arranged on the side of the rear wheels, and the transmission case. A transmission case cover attached to the transmission case, a kick drive gear driven by the rotation of the kick shaft, and a kick drive gear that mesh with each other and are provided on the crankshaft of the internal combustion engine so as to form a belt chamber for accommodating the machine. It is known that the kick ratchet is provided with a kick driven gear that can be freely engaged and detached, and the kick shaft is supported by a transmission case cover.

The transmission case cover of the conventional power unit for saddle-type vehicles is generally made of metal such as aluminum in order to secure the rigidity to support the kick shaft, and the transmission case and the transmission case cover are used to form a belt chamber. If this is provided, it becomes an issue to increase the weight and cost of the large metal transmission case cover.

JP-A-2007-132413

The present invention has been invented in order to overcome the above difficulties, and an object of the present invention is to reduce the weight of the transmission case cover, reduce the weight of the entire power unit, and reduce the cost while ensuring the rigidity to support the kick shaft. It is to provide a power unit for a saddle-type vehicle with a kick start device that can reduce the amount.

The present invention is a belt-type continuously variable transmission having a drive pulley provided on a crankshaft of an internal combustion engine, a driven pulley provided on a driven shaft provided behind the drive pulley, and a belt wound around the drive pulley and the driven pulley. The transmission is
It is housed in a belt chamber formed by a transmission case connected to the engine body of the internal combustion engine and arranged on the side of the rear wheel and a transmission case cover attached to the transmission case.
A kick shaft provided so as to penetrate the transmission case cover,
The kick drive gear driven by the rotation of the kick shaft and
In a power unit for a saddle-mounted vehicle with a kick starting device, which is driven by the kick drive gear and is provided with a kick driven gear that can be engaged with and detached from the kick ratchet provided on the crankshaft.
The transmission case cover is made of resin and
A metal support member that is formed separately from the transmission case cover and supports the kick shaft.
It is fastened to the metal transmission case so as to be arranged inside the belt chamber.
The support member includes a first bearing portion that pivotally supports a kick shaft provided with the kick drive gear.
A second bearing portion that pivotally supports a driven shaft provided with the kick driven gear, and
A support plate portion to which the first bearing portion and the second bearing portion are fixed, and
It has an upper support leg portion and a lower support leg portion that extend from the support plate portion toward the upper part and the lower part of the transmission case and are fastened to the transmission case in a side view.
A constricted portion is provided at a portion of the support plate portion of the support member that connects the first bearing portion and the second bearing portion, and the constricted portion is a locus of an outer peripheral surface of the kick drive gear and the drive. It is tied from the outer peripheral surface of the pulley to the inside ,
The transmission case cover is formed with a cooling air intake that takes in cooling air from the outside into the belt chamber at the front portion thereof.
The inner wall surface of the transmission case cover and the plate member attached to the inner wall surface of the transmission case cover form an air guide path for guiding the cooling air taken in from the cooling air intake port to the drive pulley.
The support plate portion is a kick start device for a power unit for a saddle-type vehicle, which is provided at a position near the transmission case cover in the air guide path .

Since the belt chamber is formed of a metal transmission case and a resin transmission case cover, it is possible to reduce the weight and cost of the large transmission case cover. At this time, since the kick shaft is pivotally supported by a metal support member formed separately from the transmission case cover, the support rigidity of the kick shaft can be ensured. Further, the support member can be a relatively small one arranged inside the belt chamber, and can contribute to weight reduction of the power unit. Further, since the support member is fastened to the metal transmission case, the load from the kick shaft is less likely to be transmitted to the resin transmission case cover, and the durability of the transmission case cover can be improved.

In the above configuration, the kick shaft may be arranged in front of the driven pulley, and the support member may be provided only in a region in the belt chamber on the front side of the driven pulley.

According to the above configuration, by providing the support member only in the region on the front side of the driven pulley in the belt chamber, the support member can be compactly formed while supporting the kick shaft, further reducing the weight of the power unit. Can contribute effectively.

Further, in the above configuration, the transmission case cover is formed with a cooling air intake port for taking in cooling air from the outside into the belt chamber at the front portion thereof, and is rearward of the cooling air intake port and forward of the driven pulley. Is provided with an exhaust duct having a cooling air outlet for discharging the cooling air.
The support member may be provided only in the region on the front side of the exhaust duct in the belt chamber.

According to the above configuration, by providing the support member only in the region on the front side of the driven pulley in the belt chamber, the support member can be compactly formed while supporting the kick shaft, further reducing the weight of the power unit. Can contribute effectively. Further, since the support member is provided in the area on the front side of the exhaust duct, the support member can be provided so as not to overlap the exhaust duct in the front-rear direction, and the support member is prevented from interfering with the exhaust air. Therefore, smooth ventilation can be performed.

Roughly, in the configuration, the support member includes a first bearing portion that pivotally supports a kick shaft provided with the kick drive gear.
A second bearing portion that pivotally supports the driven shaft provided with the kick driven gear, and
A support plate portion to which the first bearing portion and the second bearing portion are fixed, and
It may have an upper support leg portion and a lower support leg portion that extend from the support plate portion toward the upper portion and the lower portion of the transmission case and are fastened to the transmission case in a side view.

According to the above configuration, the support rigidity around the kick shaft can be efficiently increased by the upper support leg portion and the lower support leg portion.

Furthermore, in the above configuration, the transmission case cover is formed with a cooling air intake port for taking in cooling air from the outside into the belt chamber at the front portion thereof.
The inner wall surface of the transmission case cover and the plate member attached to the inner wall surface of the transmission case cover form an air guide path for guiding the cooling air taken in from the cooling air intake port to the drive pulley.
The support plate portion may be provided at a position closer to the transmission case cover in the air guide path.

According to the above configuration, when the inner wall surface of the transmission case cover and the plate member attached to the inner wall surface form the air guide path, even if the support member is arranged in the air guide path. Since this support member is provided at a position near the transmission case cover in the air guide path, it is possible to prevent the support member from interfering with the air guide, and smoothly flow the cooling air from the cooling air intake port to the drive pulley. I can guide you.

In the above configuration, the transmission case cover is fastened to the transmission case together with the support member, and the transmission case cover is fastened to the transmission case.
The transmission case cover is formed with an engaging portion for positioning the support member on the transmission case cover.
The support member to which the kick shaft and the driven shaft are pivotally supported on the transmission case cover and the plate member may be attached to the transmission case in a state of being preliminarily assembled.

According to the above configuration, since the transmission case cover and the support member are fastened together to the transmission case, the fastening structure can be simplified. Since the support member is arranged in the belt chamber, if the transmission case cover and the support member are to be fastened together, it is difficult to visually recognize the support member from the outside, and the joint tightening work in this state is difficult. It becomes. On the other hand, when the joint fastening is performed, an engaging portion is formed in the transmission case, and the support member can be positioned on the engaging portion, so that the assembly workability can be improved. Further, since the support member on which the kick shaft and the driven shaft are pivotally supported on the transmission case cover and the plate member are attached to the transmission case in a pre-assembled state, the assembling property can be further improved. ..

Further, in the above configuration, the transmission case cover is fastened to the transmission case by tightening together with the support member.
The transmission case cover may be formed with an engaging portion for positioning the support member on the transmission case cover.

According to the above configuration, since the transmission case cover and the support member are fastened together to the transmission case, the fastening structure can be simplified. Since the support member is arranged in the belt chamber, if the transmission case cover and the support member are to be fastened together, it is difficult to visually recognize the support member from the outside, and the joint tightening work in this state is difficult. It becomes. On the other hand, when the joint fastening is performed, an engaging portion is formed in the transmission case, and the support member can be positioned on the engaging portion, so that the assembly workability can be improved.

Further, in the above configuration, a return spring for urging the kick shaft toward the initial position may be attached to the support member.

According to the above configuration, since the return spring is attached to the metal support member instead of the resin transmission case cover, the load transmitted to the transmission case cover side can be suppressed.

According to the present invention, since the belt chamber is formed of the metal transmission case and the resin transmission case cover, it is possible to reduce the weight and cost of the large transmission case cover.

It is a left side view of the main part of the motorcycle which mounted the power unit for the saddle type vehicle with the kick start device which concerns on one Embodiment of this invention. FIG. 1 is a cross-sectional development view of a power unit cut in the direction of the arrow II-II. It is a left side view of a power unit. It is an enlarged view of the main part around the kick start device of FIG. FIG. 3 is a cross-sectional view taken along the line VV. It is a perspective view around the kick start device of a power unit with the transmission case cover omitted. It is the figure which looked at the transmission case cover with the support member and the plate member attached from the inside. FIG. 3 is a cross-sectional view taken along the line VIII-VIII. It is a perspective view which showed the support member used for the power unit for a saddle type vehicle with a kick start device of another embodiment.

A power unit P for a saddle-mounted vehicle with a kick starting device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8. In FIG. 6, the transmission case cover 30 is omitted to show the main part of the power unit P.

The orientations of the front, back, left, right, up and down, etc. within the scope of the description and claims of the present specification shall follow the orientation of the vehicle with the power unit P according to the present embodiment mounted on the vehicle. In the present embodiment, the saddle-mounted vehicle is a scooter-type motorcycle. In the figure, the arrow FR indicates the front of the vehicle, LH indicates the left side of the vehicle, RH indicates the right side of the vehicle, and UP indicates the upper part of the vehicle.

FIG. 1 shows a swing-type power unit P according to the present embodiment in a state of being attached to a scooter-type motorcycle (“saddle-type vehicle” in the present invention; hereinafter, simply referred to as “motorcycle”) 1. FIG. 1 shows only the rear part of the vehicle body of the motorcycle 1.

In the motorcycle 1, the front part of the vehicle body and the rear part 1R of the vehicle body (not shown) are connected to each other via a low floor portion 1C, and the body frame forming the skeleton of the vehicle body is generally a down frame (not shown) and a main frame 2. Consists of.

That is, a down frame (not shown) extends downward from a head pipe (not shown) at the front of the vehicle body, the down frame bends horizontally at the lower end and extends rearward below the floor portion 1C, and a pair of left and right main frames 2 at the rear end. Is connected via a cross frame 2b, and the main frame 2 rises diagonally rearward from the cross frame 2b, bends horizontally at a predetermined height, and extends rearward.

A fuel tank and a storage box (not shown) are supported by the main frame 2, and a seat (not shown) is arranged above the fuel tank and the storage box.

A swing-type power unit P is swingably connected and supported on a connecting member 2a at the lower end of a rising portion of the main frame 2 via a link member 3.

A single-cylinder 4-stroke cycle internal combustion engine 20 is mounted on the power unit P in a position in which the cylinder block 22 is tilted forward to a state close to horizontal, and is mounted on the crankcase of the unit case 21 of the power unit P. The end of the hanger bracket 21h projecting forward from the lower end of the corresponding portion is connected to the link member 3 via the pivot shaft 3a.

A belt-type continuously variable transmission 25 is configured from the left half of the internal combustion engine 20 to the rear, and a rear wheel 8 is pivotally supported by a reduction mechanism 28 provided at the rear.

Above the power unit P, the intake pipe 12 extends from the upper part of the cylinder head 23 that is greatly tilted forward of the internal combustion engine 20, and the connecting tube 14 is connected to the intake pipe 12 that is curved rearward via the throttle body 13. The air cleaner device 15 is connected to the connecting tube 14 extending rearward, and the air cleaner device 15 is attached to the upper part of the unit case 21.

A step plate 4 is stretched on the floor portion 1C. Lower side covers 5 are extended downward along the left and right side edges of the step plate 4. The lower side cover 5 extends obliquely upward from the floor portion 1C and covers the side of the cylinder block 22 and the cylinder head 23 of the internal combustion engine 20.

In the vehicle body rear portion 1R, a body cover 6 connected to the upper end edge of the lower side cover 5 covers the left and right sides of the main frame 2.

The main stand 7 is pivotally attached to the bracket 21k projecting from the lower part of the unit case 21.

FIG. 2 is a cross-sectional view of the power unit P cut and developed substantially along the line II-II of FIG.

The unit case 21 is made of metal and is composed of a left and right split left unit case 21L and a right unit case 21R combined. The right unit case 21R forms a half body of the crankcase and the left unit. The case 21L is long in the front-rear direction and includes a front crankcase portion 21a, a central transmission case portion 21b, and a rear reduction gear case portion 21c.

The left open surface of the left unit case 21L is covered with a transmission case cover 30 which is a part of the transmission case, the belt type continuously variable transmission 25 is housed inside, and the right open surface of the rear reducer case portion 21c. Is covered by a speed reducer case 27, which is a part of the transmission case, and a speed reduction mechanism (reduction gear train) 28 is housed inside.

In the so-called crankcase of the crankcase portion 21a and the right unit case 21R, the crankshaft 40 is rotatably supported by the left and right main bearings 41 and 41, and of the extension portions extending in the left and right horizontal directions, it extends to the right. An AC generator 60 is provided in the portion, and a drive sprocket 55 and a drive pulley 76 of the belt-type continuously variable transmission 25 are provided in the left extension portion.

In the internal combustion engine 20, a connecting rod 43 connects a piston 42 that reciprocates in the cylinder liner 44 of the cylinder block 22 and a crank pin 40a of the crankshaft 40.

The 4-cycle internal combustion engine 20 employs a SOHC type valve system. A valve mechanism 50 is provided in the cylinder head cover 24, and a camchain 51 that transmits drive to the valve mechanism 50 is a camshaft. It is erected between 53 and the crankshaft 40, and a cam chain chamber 52 for that purpose is provided so as to communicate with the crankcase portion 21a, the cylinder block 22, and the cylinder head 23.

That is, the cam chain 51 passes through the cam chain chamber 52 between the driven sprocket 54 fitted to the left end of the cam shaft 53 oriented in the left-right horizontal direction and the drive sprocket 55 fitted to the crank shaft 40. It has been laid. The spark plug 45 is fitted diagonally toward the combustion chamber in the cylinder head 23.

In the AC generator 60 provided on the right side surface of the right unit case 21R, a bowl-shaped outer rotor 62 is fixed to the end of the crankshaft 40 protruding from the central cylindrical portion 21d of the right unit case 21R via an ACG boss 61. A stator 64 around which a stator coil 65 is wound is fixed to a central cylindrical portion 21d inside a magnet 63 arranged on an inner peripheral surface in the circumferential direction.

A forced air cooling fan 66 is attached to the right side surface of the outer rotor 62, a fan cover 67 covers the side thereof, and a shroud 68 is provided which is connected to the fan cover 67 and covers the cylinder block 22 and the cylinder head 23.

Inside the curved shroud 68 on the right side, a cooling air passage 68p that guides cooling air from the forced air cooling fan 66 to the cylinder head 23 is formed by an inner wall 68i.

In the crankcase portion 21a of the unit case 21, the cam chain chamber 52 is formed so as to be separated from the crank chamber by a main bearing 41, and the left wall of the cam chain chamber 52 is further left with the belt chamber 70 and the cam. A partition wall 71 that separates the chain chamber 52 from the chain chamber 52. A seal member 72 is press-fitted into the circular opening through which the crankshaft 40 penetrates, and the crankshaft 40 penetrates the hollow portion of the seal member 72. There is.

The drive sprocket 55 is fitted to the crankshaft 40 between the seal member 72 and the main bearing 41, and the cam chain 51 is wound around the drive sprocket 55. The belt chamber 70 is liquid-tightly separated from the cam chain chamber 52 by the seal member 72 to prevent oil from leaking to the belt chamber 70.

As shown in FIG. 2, a drive pulley 76 is integrally rotatably provided on the crankshaft 40 extending through the seal member 72.

The drive pulley 76 is composed of a fixed side pulley half body 77 and a movable side pulley half body 78, and the fixed side pulley half body 77 is fixed to the left end of the crankshaft 40 by a ratchet member 79, and the movable side pulley is fixed to the right side thereof. The half body 78 is supported by the crankshaft 40, and the movable side pulley half body 78 rotates together with the crankshaft 40 and can slide in the axial direction to approach and separate from the fixed side pulley half body 77. The V-belt 75 is sandwiched between the pulley halves 77 and 78 and wound around.

A cam plate 80 is provided at a fixed position close to the seal member 72 on the right side of the movable pulley half body 78, and a slide piece 80a provided at the outer peripheral end thereof is axially located at the outer peripheral end of the movable pulley half body 78. It is slidably engaged with the sliding groove 78a formed so as to be oriented toward.

The side surface of the movable pulley half body 78 on the cam plate 80 side has a tapered shape toward the cam plate 80 side, and the dry weight roller 81 is accommodated between the cam plates 80 inside the tapered surface.

Therefore, when the rotation speed of the crankshaft 40 increases, the dry weight roller 81 between the movable pulley half body 78 and the cam plate 80, which rotates together, moves in the centrifugal direction due to centrifugal force, and the movable pulley half body 78 is dry. Pressed by the weight roller 81, it moves to the left and approaches the fixed side pulley half body 77, and the V-belt 75 sandwiched between the two pulley half bodies 77 and 78 is moved in the centrifugal direction to increase the winding diameter. It is configured as follows.

In the rear driven pulley 86 corresponding to the drive pulley 76, the fixed side pulley half body 87 is fitted to the inner sleeve 89 which is rotatably supported relative to the speed reducer input shaft 95 of the reduction mechanism 28, and the fixed side is fixed. On the left side of the pulley half body 87, the movable side pulley half body 88 is externally supported so as to be relatively movable to the inner sleeve 89, and is composed of both pulley half bodies 87 and 88.

A guide pin 89p projecting from the inner sleeve 89 is slidably fitted into the spiral elongated hole 90h of the driven shaft 90 to form a torque cam mechanism. The V-belt 75 is sandwiched between the pulley halves 87 and 88. A centrifugal clutch 91 is provided on the left side of the speed reducer input shaft 95 and the inner sleeve 89.

In the centrifugal clutch 91, a clutch outer 93 covering the outer periphery of the clutch inner 92 fitted to the inner sleeve 89 is fitted to the speed reducer input shaft 95, and the clutch inner 92 swings in the centrifugal direction against the spring 92b. A moving clutch shoe 92s is provided so as to face the inner peripheral surface of the clutch outer 93.

Therefore, when the rotation speed of the power transmitted to the inner sleeve 89 via the V-belt 75 increases, the clutch shoe 92s swings in the centrifugal direction against the spring 92b and reaches the inner peripheral surface of the clutch outer 93. The centrifugal clutch 91 is engaged in contact with the clutch, and is transmitted to the reduction gear input shaft 95, and is transmitted to the rear axle 96 via the reduction mechanism 28 to rotate the rear wheel 8.

As shown in FIG. 2, the transmission case portion 21b provided on the left unit case 21L connected to the engine body of the internal combustion engine 20 and arranged on the side of the rear wheel 8 is transmitted so as to cover from the left side. The case cover 30 is attached. The space formed by the transmission case portion 21b and the transmission case cover 30 is a belt chamber 70. As shown in FIG. 3, the transmission case cover 30 is made of resin and has an elongated oval shape in the front-rear direction when viewed from the side, and is rearward from the front drive pulley 76 as shown in FIG. It is formed so as to cover up to the centrifugal clutch 91 of.

A drive pulley 76 provided on the crankshaft 40 of the internal combustion engine 20, a driven pulley 86 provided on a driven shaft 90 provided behind the drive pulley 76, and a V-belt 75 wound around the drive pulley 76 and the driven pulley 86. The belt-type continuously variable transmission 25 is housed in a belt chamber 70 composed of a transmission case 21b and a transmission case cover 30.

The transmission case cover 30 is provided on the upper surface of the cover main body 31 that covers the left side of the belt-type continuously variable transmission 25 and the front portion of the cover main body 31 and communicates with the inside of the belt chamber 70 to allow outside air to flow into the belt chamber 70. It is equipped with a cooling air intake pipe 32 to be taken in. The cover main body portion 31 is roughly composed of a side wall portion 31a having an oval shape in a side view and a peripheral wall portion 31b surrounding the outer circumference, and a kick shaft 10 is inserted in the front side of the side wall portion 31a. A hole 31c is provided.

As shown in FIGS. 3 and 7, a plurality of mounting boss portions 36 for mounting on the transmission case portion 21b are provided around the peripheral wall portion 31b of the transmission case cover 30 so as to project outward. One on the front side of the upper part, two on the front side of the lower part, and an engaging mounting boss portion 37 are provided. The engaging mounting boss portion 37 is formed with an engaging portion 37a that is engaged with the engaging protrusions 104c and 105c of the support member 100 described later and positions the support member 100 on the transmission case cover 30.

The upper end of the cooling air intake pipe 32 of the transmission case cover 30 is the cooling air intake 33 into the belt chamber 70. A duct 48 is attached to the cooling air intake pipe 32, and the upper end of the duct 48 is an opening 48a formed with a low front portion and a high rear portion in a side view, and the vehicle body of the motorcycle 1 The outside air flowing between the body cover 6 and the body cover 6 can be easily taken into the belt chamber 70.

As shown in FIG. 7, the inner surface of the side wall portion 31a of the cover main body portion 31 of the transmission case cover 30 is substantially at the center of the transmission case cover 30 in the front-rear direction and behind the cooling air intake 33. A tubular case exhaust duct 34 is formed so as to be located between the drive pulley 76 and the centrifugal clutch 91 so as to face vertically along the inner surface of the side wall.

The upper end opening 34a of the case exhaust duct 34 is open to the inside of the belt chamber 70, the lower end opening 34b is open to the outside of the belt chamber 70, and the lower end opening 34b of the case exhaust duct 34 is the belt chamber. It has 70 cooling air outlets 35. As shown in FIG. 2, the cooling air outlet 35 is provided so as to be located in front of the driven pulley 86. The air taken into the belt chamber 70 from the cooling air intake 33 cools the belt-type continuously variable transmission 25 and is discharged to the outside from the cooling air outlet 35 of the case exhaust duct 34.

As shown in FIG. 6, a metal support member 100 (see FIG. 7) formed separately from the transmission case cover 30 and supporting the kick shaft 10 is attached to the inner wall surface 30a of the transmission case cover 30. Has been done. The support member 100 is fastened to the transmission case 21b together with the transmission case cover 30 by bolts 128, and is arranged inside the belt chamber 70 as shown in FIG.

The support member 100 pivotally supports the first bearing portion 102 provided with the kick shaft 10 provided with the kick drive gear 120 and the driven shaft 122 provided with the kick driven gear 123, with reference to FIGS. 4 to 6. The second bearing portion 103, the support plate portion 101 to which the first bearing portion 102 and the second bearing portion 103 are fixed, and the support plate portion 101 extending from the support plate portion 101 toward the upper part and the lower part of the transmission case 21b in a side view, respectively. It has an upper support leg portion 104 and a lower support leg portion 105 to be fastened to the transmission case 21b.

A cylindrical first bearing portion 102 is integrally fixed to the rear portion of the support plate portion 101 formed on a substantially flat plate by welding. As shown in FIG. 4, a collar 107 is fitted inside the first bearing portion 102, and the kick shaft 10 is rotatably supported through the collar 107.

A kick drive gear 120 is fitted to the inner end of the kick shaft 10, and a return spring 121 is wound around the outer circumference of the first bearing 102 so that the kick shaft 10 is directed to the initial position. One end 121a of the return spring 121 is engaged with the first bearing portion 102, the other end 121b is wound around the spring mounting portion 106 protruding inward of the support plate portion 101 of the support member 100, and the kick shaft 10 is It is urged by the return spring 121.

The left end of the kick shaft 10 projects outward from the kick shaft insertion hole 31c provided in the cover main body 31 of the transmission case cover 30, and the base end of the kick arm 11 is fitted to the tip of the kick arm 11. , The kick pedal 11p is attached undulatingly.

A tubular second bearing portion 103 is attached to the front portion of the support member 100 by welding. A driven shaft 122 is rotationally supported on the second bearing portion 103 so as to be rotatable and slidable in the axial direction in coaxial with the crank shaft 40, and a kick driven gear 123 is formed on the driven shaft 122 to form the kick driven gear. Along with meshing with 120, a ratchet wheel 124 is fixed to the right end, and the whole is urged to the left by a friction spring 125.

On the other hand, the ratchet member 79, which is fixed by pressing the fixed side pulley half body 77 to the crankshaft 40, has a ratchet formed opposite to the ratchet wheel 124, and both can be brought into contact with each other by sliding the driven shaft 122. is there. With this configuration, the kick driven gear 123 meshes with the kick drive gear 120 and is freely engaged with and detached from the ratchet member 79 provided on the crankshaft 40 by the ratchet wheel 124.

Therefore, when the kick pedal 11p is stepped on and the kick shaft 10 rotates against the return spring 121, the kick drive gear 120 rotates integrally with the kick shaft 10, and the kick drive gear 120 is driven by the rotation of the kick shaft 10. To. The kick driven gear 123 that meshes with the kick drive gear 120 protrudes to the right against the friction spring 125 while rotating integrally with the driven shaft 122, and the ratchet wheel 124 meshes with the ratchet of the ratchet member 79 to engage the crankshaft 40. The internal combustion engine 20 can be started by forcibly rotating it.

As shown in FIG. 6, the support plate portion 101 is formed with an upper support leg portion 104 extending upward from the first bearing portion 102 and a lower support leg portion 105 extending downward. Has been done. Further, the support plate portion 101 extends diagonally downward and forward from the second bearing portion 103 to form a lower support leg portion 105.

As shown in FIGS. 6 and 7, the upper support leg 104 and the lower support leg 105 extend outward along the same plane from the support plate 101 and are bent to form the transmission case cover 30. Leg portions 104a and 105a extending to the engagement mounting boss portion 37 of the above are formed. Mounting pieces 104b, 105b that come into contact with the surface of the boss portion 21b ₁ of the transmission case 21b are provided at the ends of the legs 104a, 105a, and engage with the transmission case cover 30 side from the mounting pieces 104b, 105b. The protrusions 104c and 105c are provided.

The engaging protrusions 104c and 105c are formed in a cylindrical shape as shown in FIG. 6, and are inserted into the engaging portion 37a formed in a circular hole in the engaging mounting boss portion 37 of the transmission case cover 30 (FIG. 6). 8), the support member 100 is positioned on the transmission case cover 30.

The support member 100 to which the kick shaft 10, the driven shaft 122, the return spring 121, the kick driven gear 123 and the ratchet wheel 124 are attached has its engaging protrusions 104c and 105c engaged with the engaging portion 37a, and is a transmission case. It is temporarily fixed to the cover 30, and then, as shown in FIG. 7, a screw 112 is screwed onto the substantially flat plate member 110, and the plate member 110 is attached to the transmission case cover 30.

As shown in FIG. 7, the plate member 110 is formed so as to cover substantially the entire support member 100 except for the mounting pieces 104b and 105b, and these can be inserted around the driven shaft 122 and the ratchet wheel 124. As described above, a circular opening 110b is provided. The opening 110b is an opening for passing the cooling air taken in from the cooling air intake 33 to the drive pulley 76 side. As shown in FIG. 2, the kick shaft 10 is arranged in front of the driven pulley 86, and the support member 100 is provided only in the region on the front side of the driven pulley 86 in the belt chamber 70. Further, as shown in FIG. 7, the support member 100 is provided in a region on the front side of the upper end opening 34a of the case exhaust duct 34 in the belt chamber 70.
The case exhaust duct 34 may be formed separately from the transmission case 30.

As shown in FIGS. 4 and 5, the air guide path 130 that guides the cooling air taken in from the cooling air intake 33 to the drive pulley 76 by the inner wall surface 30a of the transmission case cover 30 and the plate member 110. Is formed. As shown in FIG. 5, the support plate portion 101 of the support member 100 is provided at a position closer to the transmission case cover 30 in the air guide path 130 and does not obstruct the flow of the cooling air passing through the air flow path 130. It has become like. More specifically, the first bearing portion 102, the second bearing portion 103, and the support plate portion 101 of the support member 100 are arranged outside the plate member 110 in the vehicle width direction, and are arranged on the axis of the crankshaft 40. The support plate portion 101 is provided at a position closer to the transmission case cover 30 than the plate member 110 in the direction along the line.

The transmission case cover 30, the support member 100, and the plate member 110 described above are attached to the transmission case portion 21b as follows. As shown in FIG. 7, the transmission case portion 21b of the unit case 21 is in a state in which the support member 100 and the plate member 110 on which the kick shaft 10 and the driven shaft 122 are pivotally supported are assembled in advance on the transmission case cover 30. Is in contact with. After that, as shown in FIG. 8, the bolt 39 is inserted into the engaging mounting boss portion 37 of the transmission case cover 30 and the engaging protrusions 104c and 105c of the support member 100, and the boss portion of the transmission case portion 21b is inserted. It is screwed into the screw hole 21b _{2 of} 21bq, and the transmission case cover 30 is attached to the transmission case portion 21b by tightening together with the support member 100.

Since the power unit P for the saddle-mounted vehicle with the kick start device of the present embodiment is configured as described above, the following effects are obtained.

In the power unit P of the present embodiment, the transmission case cover 30 is made of resin, is formed separately from the transmission case cover 30, and the metal support member 100 that pivotally supports the kick shaft 10 is the belt chamber 70. Since it is fastened to the metal transmission case portion 21b so as to be arranged inside, the belt chamber 70 is formed by the metal transmission case portion 21b and the resin transmission case cover 30, and is therefore large. It is possible to reduce the weight and cost of the transmission case cover 30.

Further, since the kick shaft 10 is pivotally supported by the first bearing portion 102 of the metal support member 100, the support rigidity of the kick shaft 10 can be ensured. Further, the support member 100 can be a relatively small one arranged inside the belt chamber 70, and can contribute to weight reduction of the power unit P. Further, since the support member 100 is fastened to the metal transmission case portion 21b, the load from the kick shaft 10 is less likely to be transmitted to the resin transmission case cover 30, and the durability of the transmission case cover 30 can be improved.

Further, since the kick shaft 10 is arranged in front of the driven pulley 86 and the support member 100 is provided only in the region on the front side of the driven pulley 86 in the belt chamber 70, the support member 100 uses the kick shaft 10. It can be formed compactly while being supported, and can contribute more effectively to the weight reduction of the power unit P.

Further, the transmission case cover 30 is formed with a cooling air intake 33 of a cooling air intake pipe 32 that takes in cooling air from the outside into the belt chamber 70 at the front portion thereof, and a driven pulley 87 behind the cooling air intake 33. A case exhaust duct 34 having a lower end opening 34b as a cooling air outlet 35 for discharging cooling air is provided in front of the support member 100, and the support member 100 is placed on the front side of the cooling air outlet 35 in the belt chamber 70. Since the support member 100 is provided only in the region of the above, the support member 100 can be formed compactly while supporting the kick shaft 10, and can more effectively contribute to the weight reduction of the power unit P. Further, since the support member 100 is provided in the region on the front side of the case exhaust duct 34, the support member 100 can be provided so as not to overlap the case exhaust duct 34 in the front-rear direction, and the support member 100 can be provided to exhaust air. It is possible to suppress the obstruction of the air and to perform smooth ventilation.

Furthermore, the support member 100 includes a first bearing portion 102 that pivotally supports the kick shaft 10 provided with the kick drive gear 120, and a second bearing portion 103 that pivotally supports the driven shaft 122 provided with the kick driven gear 123. The support plate portion 101 to which the first bearing portion 102 and the second bearing portion 103 are fixed, and the transmission case portion 21b extending from the support plate portion 101 toward the upper part and the lower part of the transmission case portion 21b in a side view, respectively. Since it has an upper support leg 104 and a lower support leg 105 that are fastened to the boss portion 21b ₁ , the upper support leg 104 and the lower support leg 105 support the circumference of the kick shaft 10. Rigidity can be increased efficiently.

Further, the transmission case cover 30 is formed with a cooling air intake 33 that takes in cooling air from the outside into the belt chamber 70 at the front portion thereof, and the inner wall surface 30a of the transmission case cover 30 and the inside of the transmission case cover 30. A plate member 110 attached to the wall surface 30a forms an air guide 130 that guides the cooling air taken in from the cooling air intake 33 to the drive pulley 76, and the support plate 101 is transmitted in the air passage 130. Since it is provided at a position closer to the case cover 30, when the inner wall surface 30a of the transmission case cover 30 and the plate member 110 attached to the inner wall surface 30a form the air guide path 130, the inside of the air guide path 130 is formed. Even when the support member is arranged in, the support member 100 can be prevented from interfering with the air guide, and the cooling air can be smoothly guided from the cooling air intake 33 to the drive pulley 76. it can.

Further, the fastening structure can be simplified by fastening the transmission case cover 30 and the support member 100 together to the transmission case portion 21b. Further, since the support member 100 is arranged in the belt chamber 70, if the transmission case cover 30 and the support member 100 are to be fastened together, it is difficult to visually recognize the support member 100 from the outside, and the support member 100 is in this state. The tightening work becomes difficult. On the other hand, when the joint tightening is performed, an engaging portion 37b is formed on the transmission case cover 30, and the engaging protrusions 104c and 105c of the support member 100 can be positioned on the engaging portion 37b. Therefore, the assembly workability can be improved. Further, the support member 100 on which the kick shaft 10 and the driven shaft 122 are pivotally supported on the transmission case cover 30 and the plate member 110 are attached to the transmission case portion 21b in a pre-assembled state, so that the assembly is easy. Can be further improved.

The transmission case cover 30 may be fastened together with the support member 100 to the transmission case portion 21b, and the transmission case cover 30 may be formed with an engaging portion for positioning the support member 100 on the transmission case cover 30. ..

According to the above configuration, since the transmission case cover 30 and the support member 100 are fastened together to the transmission case portion 21b, the fastening structure can be simplified. Since the support member 100 is arranged in the belt chamber 70, if the transmission case cover 30 and the support member 100 are to be fastened together, it is difficult to visually recognize the support member 100 from the outside, and the support member 100 is in this state. The tightening work becomes difficult. On the other hand, when the joint tightening is performed, the transmission case cover 30 is formed with an engaging portion 37a, and the support member 100 can be positioned on the engaging portion 37a, so that the assembly workability is improved. be able to.

Further, since the return spring 121 is attached to the metal support member 100 instead of the resin transmission case cover 30, the load transmitted to the transmission case cover 30 side can be suppressed.

In the above-described embodiment, the support member 100 provided with one upper support leg 104 and two lower support legs 105 was used, but as shown in FIG. 9, the support member 100 is replaced with the support member 100. Support member 200 may be used. The support member 200 includes a first bearing portion 202 that pivotally supports the kick shaft 10 provided with the kick drive gear 120, a second bearing portion 203 that pivotally supports the driven shaft 122 provided with the kick driven gear 123, and a first bearing. The support plate portion 201 to which the portion 102 and the second bearing portion 103 are fixed, and the support plate portion 101 extending from the support plate portion 101 toward the upper part and the lower part of the transmission case 21b, respectively, are fastened to the transmission case portion 21b. It has an upper support leg portion 204 and a lower support leg portion 205.

The upper support leg portion 204 extends upward from the first bearing portion 202, and the lower support leg portion 205 extends downward. Further, from the second bearing portion 203, the upper support leg portion 204 is formed so as to extend upward, and the lower support leg portion 205 is formed so as to extend downward. The upper support leg portion 204 and the lower support leg portion 205 are the leg portions 204a, 205a, similarly to the upper support leg portion 104 and the lower support leg portion 105 of the support member 100 used in the above-described embodiment. Mounting pieces 204b and 205b and engaging protrusions 204c and 205c are provided, and the engaging mounting boss portion 37 and the transmission case portion 21b boss portion 21b _{1 of} the transmission case cover 30 are provided with the mounting pieces 204b and 205b and the engaging protrusions. The transmission case cover 30 is provided at a position corresponding to the portions 204c and 205c (not shown), and the transmission case cover 30 is attached to the transmission case portion 21b integrally with the support member 200. In the support member 200 used in the present embodiment, since the first bearing portion 202 and the second bearing portion 203 are supported by both the upper support leg portion 204 and the lower support leg portion 205, respectively, a kick is obtained. Both the shaft 10 and the kick driven gear 123 can be firmly held by the support member 200. Further, recesses 204d and 205d are formed in the upper support leg member 204 and the lower support leg member 205. By forming the recesses 204d and 205d in this way, the rigidity of the support legs can be further increased. The recesses 204d and 205d may have a convex shape.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various other modifications can be made. Further, the power unit P for a saddle-type vehicle with a kick start device of the present invention is not limited to a motorcycle, and can be widely applied to other types of saddle-type vehicles.

1 ... Motorcycle, 10 ... Kickshaft, 20 ... Internal combustion engine, 21 ... Unit case, 21L ... Left unit case, 21b ... Transmission case, 25 ... Belt type continuously variable transmission, 30 ... Transmission case cover, 30a ... Inner wall surface , 33 ... Cooling air intake, 35 ... Cooling air outlet, 37a ... Engaging part, 40 ... Crankshaft, 70 ... Belt chamber, 75 ... V belt, 76 ... Drive pulley, 86 ... Driven pulley, 90 ... Driven shaft, 95 ... Reducer input shaft, 97 ... Kick ratchet,
100 ... Support member, 101 ... Support plate part, 102 ... First bearing part, 103 ... Second bearing part, 104 ... Upper support leg part, 105 ... Lower support leg part, 110 ... Plate member, 120 ... Kick drive gear , 121 ... Return spring,
200 ... Support member, 201 ... Support plate part, 202 ... First bearing part, 203 ... Second bearing part, 204 ... Upper support leg part, 205 ... Lower support leg part,
P ... Power unit.

Claims (6)

A drive pulley (76) provided on the crankshaft (40) of the internal combustion engine (20), a driven pulley (86) provided on a driven shaft (90) provided behind the drive pulley (76), and a drive pulley (76). A belt-type continuously variable transmission (25) having a belt (75) wound around the driven pulley (86).
A transmission case (21b) connected to the engine body of the internal combustion engine (20) and arranged on the side of the rear wheel (8), and a transmission case cover (30) attached to the transmission case (21b). Housed in the belt chamber (70) formed
A kick shaft (10) provided so as to penetrate the transmission case cover (30),
The kick drive gear (120) driven by the rotation of the kick shaft (10) and
A saddle-mounted vehicle with a kick starting device, which is driven by the kick drive gear (120) and is provided with a kick ratchet (79) provided on the crankshaft (40) and a kick driven gear (123) that can be freely engaged and disengaged. In the power unit for
The transmission case cover (30) is made of resin and is made of resin.
A metal support member (100,200) formed separately from the transmission case cover (30) and supporting the kick shaft (10) is
It is fastened to the metal transmission case (21b) so as to be arranged inside the belt chamber (70).
The support member (100,200) includes a first bearing portion (102,202) that pivotally supports a kick shaft (10) provided with the kick drive gear (120).
The second bearing portion (103, 203) that pivotally supports the driven shaft (122) provided with the kick driven gear (123), and
A support plate portion (101) to which the first bearing portion (102,202) and the second bearing portion (103,203) are fixed,
The upper support legs (104) and the lower support extending from the support plate portion (101) toward the upper part and the lower part of the transmission case (21b) and fastened to the transmission case (21b) in a side view. With legs (105)
The support member (100,200) has a constricted portion at a portion connecting the first bearing portion (102,202) and the second bearing portion (103,203) of the support plate portion (101), and the constricted portion is the said. The locus of the outer peripheral surface of the kick drive gear (120) and the inner side of the outer peripheral surface of the drive pulley (76) are bound .
The transmission case cover (30) is formed with a cooling air intake (33) at its front portion for taking in cooling air from the outside into the belt chamber (70).
The inner wall surface (30a) of the transmission case cover (30) and the plate member (110) attached to the inner wall surface (30a) of the transmission case cover (30) are taken in from the cooling air intake port (33). An air guide path (130) for guiding the cooling air to the drive pulley is formed.
The support plate portion (101) is a power unit for a saddle-mounted vehicle with a kick start device, which is provided at a position closer to the transmission case cover (30) in the air guide path (130) . The kick shaft (10) is arranged in front of the driven pulley (86), and the support member (100,200) is provided only in the region of the belt chamber (70) on the front side of the driven pulley (86). The power unit for a saddle-type vehicle with a kick start device according to claim 1, wherein the power unit is provided. The transmission case cover (30) is formed with a cooling air intake port (33) for taking in cooling air from the outside into the belt chamber (70) at the front portion thereof, and is more than the cooling air intake port (33). An exhaust duct (34) having a cooling air outlet (35) for discharging cooling air is provided at the rear and in front of the driven pulley (86).
The saddle-type vehicle with a kick start device according to claim 1, wherein the support member (100, 200) is provided in a region of the belt chamber (70) on the front side of the exhaust duct (34). Power unit for. The transmission case cover (30) is formed with a cooling air intake (33) at its front portion for taking in cooling air from the outside into the belt chamber (70).
The inner wall surface (30a) of the transmission case cover (30) and the plate member (110) attached to the inner wall surface (30a) of the transmission case cover (30) are taken in from the cooling air intake port (33). An air guide path (130) for guiding the cooling air to the drive pulley is formed.
The transmission case cover (30) is fastened to the transmission case (21b) together with the support member (100,200) and is fastened to the transmission case (21b).
The transmission case cover (30) is formed with an engaging portion (37a) for positioning the support member (100,200) on the transmission case cover (30).
The support member (100,200) on which the kick shaft (10) and the driven shaft (122) are pivotally supported on the transmission case cover (30) and the plate member (110) are assembled in advance. The power unit for a saddle-mounted vehicle with a kick starting device according to any one of claims 1 to 3, wherein the power unit is attached to the transmission case (21b) . The transmission case cover (30) is fastened to the transmission case (21b) together with the support member (100,200) and is fastened to the transmission case (21b).
Claim 1 to claim 1 , wherein the transmission case cover (30) is formed with an engaging portion (37a) for positioning the support member (100, 200) on the transmission case cover (30). A power unit for a saddle-mounted vehicle with a kick starting device according to any one of 4. The kick according to any one of claims 1 to 5 , wherein a return spring (121) for urging the kick shaft (10) toward an initial position is attached to the support member (100). Power unit for saddle-mounted vehicles with a starting device.

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