JP2012052607A - Power unit for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power unit for vehicles, including an output means arranged on the outside of an engine case on one end side of a main shaft along the axial direction thereof to transmit rotational power to the side of a drive wheel, and a clutch arranged at one end of the main shaft in the axial direction thereof to disconnect/connect the rotational power to be transmitted from a crankshaft to the main shaft, while reducing the size in the axial direction of the crankshaft and reducing the number of components thereof.SOLUTION: A final shaft 48A to receive the rotational power transmitted from a counter shaft 43 has an axis parallel to that of the main shaft 33, and is supported freely rotatably in the engine case 21. The output means 49 arranged at the outside of a projected range of the clutch 41 to be projected onto a plane perpendicular to the axis of the main shaft 33 and at the inside of one end of the main shaft 33 in the axial direction thereof, is arranged at one end of the final shaft 48A projected from the engine case 21.

Description

  In the present invention, a crankshaft extending in the left-right direction of a vehicle, a main shaft having an axis parallel to the crankshaft, and a countershaft having an axis parallel to the main shaft are rotatably supported by an engine case, A gear train of a plurality of shift stages that is selectively established is provided between the main shaft and the counter shaft, and output means for transmitting rotational power from the counter shaft to the drive wheel side extends along the axial direction of the main shaft. The present invention relates to a vehicle power unit in which a clutch disposed on one end side outside the engine case and for connecting / disconnecting rotational power transmitted from the crankshaft to the main shaft is disposed at one axial end portion of the main shaft.

  A gear train of a plurality of shift stages is provided selectively between a pair of coaxially arranged main shafts and a counter shaft having an axis parallel to the main shafts, and rotational power from the counter shaft is provided. A drive sprocket, which is output means for transmitting the power to the drive wheel side, is provided at one end of the countershaft, and a pair of clutches for connecting / disconnecting rotational power transmitted from the crankshaft to the pair of main shafts, A vehicle power unit is known from Patent Document 1 that is arranged at opposite ends of both main shafts.

JP 2010-106983 A

  However, in the one disclosed in Patent Document 1, a part of the drive sprocket provided at one end of the counter shaft is disposed within the axial projection range of the clutch provided at the end of one main shaft. In order to avoid interference between the clutch and the drive sprocket, the drive sprocket is provided at one end of the countershaft protruding from the engine case, whereas one of the main shafts One end portion of the main shaft extends outward from the engine case, and the clutch is disposed at an end portion of one of the main shafts in a clutch case disposed outside the drive sprocket. . For this reason, the clutch case is arranged at a position separated from the engine case in the direction along the axis of the main shaft, and the power unit is enlarged in the direction along the axis of the crankshaft. In addition, a clutch case for housing the clutch is required, and a bearing or the like for rotatably supporting the main shaft by the clutch case is also required, which increases the number of parts.

  The present invention has been made in view of such circumstances, and has a structure in which a clutch disposed at one axial end portion of the main shaft and an output unit are disposed on the same side along the axial direction of the main shaft. An object of the present invention is to provide a vehicle power unit that can be reduced in size along the axis of the crankshaft while reducing the number of components.

  In order to achieve the above object, the present invention provides an engine case comprising a crankshaft extending in the left-right direction of a vehicle, a main shaft having an axis parallel to the crankshaft, and a countershaft having an axis parallel to the main shaft. And a gear train having a plurality of shift stages that is selectively established between the main shaft and the counter shaft, and output means for transmitting the rotational power from the counter shaft to the drive wheel side. A clutch that is disposed outside the engine case at one end side along the axial direction of the main shaft and that connects / disconnects rotational power transmitted from the crankshaft to the main shaft is disposed at one axial end portion of the main shaft. In the vehicle power unit, the rotational power from the counter shaft is transmitted. The final shaft has an axis parallel to the main shaft and is rotatably supported by the engine case. The final shaft is outside the projection range of the clutch on a plane orthogonal to the axis of the main shaft and The first feature is that the output means arranged inward in the axial direction from the one end portion in the axial direction is provided at one end portion of the final shaft protruding from the engine case.

  In addition to the configuration of the first feature, the present invention has a second feature that the output means is disposed outward in the axial direction from one axial end of the counter shaft.

  In addition to the configuration of the first or second feature, the present invention forms a part of a primary reduction gear train that transmits rotational power from the crankshaft to the main shaft, and is coaxially linked and connected to the main shaft. A third feature is that a part of the primary driven gear is disposed at a portion surrounded by the clutch, one axial end portion of the countershaft, and the final shaft.

  In addition to any of the configurations of the first to third features, the present invention provides that at least a part of the output means and the clutch when viewed in a direction orthogonal to the axes of the main shaft and the final shaft. A fourth feature is that the output means is provided at one end of the final shaft so as to overlap.

  In addition to any of the configurations of the first to fourth features, the present invention provides a final drive gear that constitutes a part of a final gear train that transmits rotational power from the counter shaft to the final shaft. A fifth feature is that the two end portions are provided near one end portion on the output means side.

  In addition to the configuration of the first or second feature, the present invention forms a part of a primary reduction gear train that transmits rotational power from the crankshaft to the main shaft, and is coaxially linked and connected to the main shaft. According to a sixth aspect of the present invention, the driven primary gear is disposed at an axially outer position than the output means in the direction along the axis of the main shaft.

  In addition to any of the configurations of the first to sixth features, the present invention provides a plurality of final gears having different gear ratios that can be alternatively established between the counter shaft and the final shaft. A seventh feature is that a column is provided.

  In addition to the configuration of the seventh feature, the present invention enables a plurality of shifters individually corresponding to the plurality of final gear trains to simultaneously establish the plurality of final gear trains to obtain a parking brake state. It is an eighth feature that it is mounted on the final shaft.

  Furthermore, the present invention, in addition to any one of the first to eighth features, transmits rotational power to a rotating shaft of a generator arranged on the same side as the clutch in a direction along the axis of the crankshaft. An ACG driving rotation member for forming a part of a primary reduction gear train that transmits rotational power from the crankshaft to the main shaft and is axially outward from a primary drive gear fixed to the crankshaft. A ninth feature is that the crankshaft is provided.

  The crankcases 22 and 152 of the embodiment correspond to the engine case of the present invention, the first main shafts 33 and 167 of the embodiment correspond to the main shaft of the present invention, and the first primary reduction gear of the embodiment. The rows 39 and 195 correspond to the primary reduction gear train of the present invention, the first clutches 41 and 181 of the embodiment correspond to the clutch of the present invention, and the first primary driven gear 47 of the embodiment corresponds to the primary driven gear of the present invention. The bevel gear mechanism 49 and the drive sprocket 133 of the embodiment correspond to the output means of the present invention, the first primary drive gear 76 of the embodiment corresponds to the primary drive gear of the present invention, and The driving sprocket 108 corresponds to the ACG driving rotary member of the present invention, and the first primary driven gear 197 of the embodiment corresponds to the primary driven gear of the present invention. That.

  According to the first aspect of the present invention, a plane perpendicular to the axis of the main shaft is provided at one end protruding from the engine case of the final shaft having an axis parallel to the main shaft and rotatably supported by the engine case. Output means disposed outside the projection range of the clutch to the outside and axially inward from the axial end of the main shaft, the clutch and output disposed at the axial end of the main shaft Even if the means is arranged on the same side along the axial direction of the main shaft, the clutch and the output means do not overlap in the axial direction, and the clutch needs to be housed in a case separate from the engine case Therefore, while avoiding mutual interference between the clutch and the output means, and reducing the number of parts, the power unit is positioned in the axial direction of the main shaft. It is possible to achieve the type of.

  According to the second feature of the present invention, since the output means is disposed axially outward from one end of the counter shaft in the axial direction, the output means and the counter shaft are not disposed even if the counter shaft and the final shaft are disposed close to each other. The power units can be made smaller without interfering with each other.

  According to the third aspect of the present invention, the engine is driven in the axial direction of the crankshaft such that a part of the primary driven gear is disposed in a portion surrounded by the clutch, the one axial end portion of the countershaft and the final shaft. The primary driven gear can be arranged while avoiding an increase in size.

  According to the fourth aspect of the present invention, at least a part of the output means overlaps with the clutch when viewed in a direction perpendicular to the axis of the main shaft and the final shaft. The amount of axial projection of the output means from the case can be suppressed.

  According to the fifth feature of the present invention, the final drive gear, which is part of the final gear train provided between the counter shaft and the final shaft, is provided near one end on the output means side of the counter shaft. It is possible to reduce the weight by minimizing the direction length.

  According to the sixth aspect of the present invention, the primary driven gear constituting a part of the primary reduction gear train provided between the crankshaft and the main shaft is located outside the output means in the direction along the axis of the main shaft. Since the shaft is coaxially linked and connected, the output means can be arranged compactly without protruding outward in the axial direction from the primary driven gear.

  According to the seventh aspect of the present invention, the plurality of final gear trains having different gear ratios are provided between the counter shaft and the final shaft. By using a plurality of final gear trains, the number of shift stages can be increased, and the degree of freedom of shift torque can be increased.

  According to the eighth aspect of the present invention, since it is possible to obtain a parking brake state using a plurality of final gear trains, it is not necessary to provide a special parking brake mechanism, thereby avoiding an increase in the number of parts. Meanwhile, the parking brake state can be obtained.

  Furthermore, according to the ninth aspect of the present invention, the ACG driving rotating member for transmitting the rotational power to the rotating shaft of the generator disposed on the same side as the clutch in the direction along the axis of the crankshaft is the primary deceleration. Since it is provided on the crankshaft axially outwardly from the primary drive gear that constitutes a part of the gear train and is fixed to the crankshaft, the ACG driving rotary member is disposed axially inward from the primary drive gear. Compared with the case where the primary driven gear and the clutch provided on the main shaft can be disposed inward in the axial direction, the axial length of the main shaft can be shortened, and the power unit can be further miniaturized.

1 is a side view of a motorcycle according to a first embodiment. It is a side view of a power unit. It is sectional drawing which follows the 3-3 line of FIG. It is a principal part enlarged view of FIG. FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG. FIG. 6 is a longitudinal sectional view showing a second embodiment and in the vicinity of one end portions of a crankshaft and a first main shaft. FIG. 10 is a longitudinal sectional view showing a third embodiment and in the vicinity of one end portions of a crankshaft and a first main shaft. It is a longitudinal cross-sectional view showing a fourth embodiment and in the vicinity of a generator. It is sectional drawing corresponding to FIG. 4 of 5th Embodiment. It is sectional drawing corresponding to FIG. 4 of 6th Embodiment. It is a side view of the power unit for vehicles of a 7th embodiment. It is sectional drawing which follows the 12-12 line of FIG. It is a principal part enlarged view of FIG.

  Embodiments of the present invention will be described with reference to the accompanying drawings.

  A first embodiment of the present invention will be described with reference to FIGS. 1 to 5. First, in FIG. 1, a body frame F of a motorcycle, which is a vehicle, steers a front fork 11 that supports a front wheel WF. A head pipe 12 that is supported, a pair of left and right main frames 13 that extend rearwardly downward from the head pipe 12, and a pair of left and right pivot plates 14 that are connected to the rear of both main frames 13 and extend downward. The rear wheel WR, which is a drive wheel, is pivotally supported at the rear part of the swing arm 15 that is pivotally supported by the pivot plate 14. In addition, a link 16 is provided between the lower part of the pivot plate 14 and the front part of the swing arm 15, and a cushion unit 17 is provided between the upper part of the pivot plate 14 and the link 16.

  A power unit PA is suspended from the main frames 13 and the pivot plates 14. Rotational power output from the power unit PA is transmitted to the rear wheel WR via a drive shaft 18 extending in the front-rear direction. A side stand 19 is attached to the lower part of the left pivot plate 14 in the vehicle body frame F.

  In FIG. 2, the engine body 20 of the engine EA that constitutes a part of the power unit PA includes a front bank BF positioned in the front in a mounted state on the motorcycle, and a rear portion positioned rearward of the front bank BF. It has a bank BR and is configured as a V-type water-cooled type, and a crankshaft 22 along the left-right direction of the motorcycle is rotatable in a crankcase 21 as an engine case common to both banks BF and BR. It is supported by.

  The crankcase 21 is formed by combining an upper case half 21a and a lower case half 21b, and is integrated with the upper case half 21a so that the front and rear cylinder blocks 23F, 23R form a V shape. The axis of the crankshaft 22 is disposed on the coupling surface of the upper case half 21a and the lower case half 21b.

  The front bank BF includes a front cylinder block 23F, a front cylinder head 24F coupled to the front cylinder block 23F, and a front head cover 25F coupled to the front cylinder head 24F. The rear bank BR Is composed of a rear cylinder block 23R, a rear cylinder head 24R coupled to the rear cylinder block 23R, and a rear head cover 25R coupled to the rear cylinder head 24R, and an oil pan 26 is disposed below the crankcase 21. Combined.

  Referring also to FIG. 3, a pair of pistons 27 is slidably fitted to the front cylinder block 23F of the front bank BF, and a pair of pistons (see FIG. 3) is also attached to the rear cylinder block 23R of the rear bank BR. (Not shown) are slidably fitted, and the pistons 27 are connected to the crankshaft 22 in common.

  A left cover 28 forming a first clutch chamber 31 is fastened between the crankcase 21 and the left side surface of the crankcase 21, and a second clutch chamber is formed between the crankcase 21 and the right side surface of the crankcase 21. The right cover 29 forming 32 is fastened. Further, one end of the crankshaft 22 passes through the crankcase 21 rotatably and protrudes into the first clutch chamber 31, and the other end of the crankshaft 22 passes through the crankcase 21 and rotates second. Project into the clutch chamber 32.

  The crankcase 21 is rotatably supported by first and second main shafts 33 and 34 that are arranged coaxially with an axis parallel to the crankshaft 22, and rotate on the left side wall of the crankcase 21. One end portion of the first main shaft 33 penetrating freely projects into the first clutch chamber 31, and a ball bearing 35 is interposed between the intermediate portion of the first main shaft 33 and the crankcase 21. A ball bearing 36 with a seal is interposed between the other end and the crankcase. The second main shaft 34 has one end portion coaxially disposed opposite the other end portion of the first main shaft 33 and the other end portion protruding into the second clutch chamber 32 so that the right side wall of the crankcase 21 is provided. A ball bearing 37 with a seal is interposed between one end portion of the second main shaft 34 and the crankcase 21, and an intermediate portion of the second main shaft 34 and the crankcase 21. A ball bearing 38 is interposed between the right side walls.

  The rotational power of the crankshaft 22 is transmitted to the first main shaft 33 via the first primary reduction gear train 39 and the first clutch 41 disposed in the first clutch chamber 31, and to the second clutch chamber 32. It is transmitted to the second main shaft 34 via the second primary reduction gear train 40 and the second clutch 42 that are arranged, and is transmitted from the crankshaft 22 to the first and second main shafts 33, 34. The first and second clutches 41 and 42 for connecting / disconnecting the rotational power are disposed at opposite ends of the first and second main shafts 33 and 34 arranged on the same axis.

  A countershaft 43 having an axis parallel to the crankshaft 22 is rotatably supported on the crankcase 21. One end of the countershaft 43 has a ball bearing 44 on the left side wall of the crankcase. The other end of the counter shaft 43 is rotatably supported on the right side wall of the crankcase 21 via a needle bearing 45.

  Between the first main shaft 33 and the counter shaft 43, first, third and fifth speed gear trains G1, G3, G5 are provided to be alternatively established, and the second main shaft 34 and the counter Between the shafts 43, second, fourth and sixth speed gear trains G2, G4, G6 are provided so as to be alternatively established.

  A final shaft 48A having an axis parallel to the counter shaft 43 is rotatably supported in the crankcase 21, and one end portion of the final shaft 48A that rotatably penetrates the left side wall of the crankcase 21 is The drive shaft 18 is linked and connected via a bevel gear mechanism 49 that is an output means for transmitting rotational power to the rear wheel WR side that is a drive wheel. Thus, a ball bearing 50 is interposed between one end of the final shaft 48A and the left side wall of the crankcase 21, and a ball bearing 51 is interposed between the other end of the final shaft 48A and the right side wall of the crankcase 21. Intervened.

  Thus, the bevel gear mechanism 49 is disposed axially inward from one axial end of the first main shaft 33 and axially outward from one axial end of the counter shaft 43, and the final shaft 48A It is provided at one end protruding from the crankcase 21.

  The rotational power of the counter shaft 43 is transmitted to the final shaft 48A via the final gear train 52 and the torque damper 53 that absorbs excessive torque generated in the torque transmission path from the crankshaft 22 to the rear wheel WR. .

  Thus, the final gear train 52 is disposed between the right side wall of the crankcase 21 and the second speed gear train G2 and meshes with the final drive gear 54 that rotates together with the counter shaft 43. And a final driven gear 55 supported on the final shaft 48A so as to be relatively rotatable.

  The torque damper 53 is opposed to the final driven gear 55 and is supported by the final shaft 48A so as not to rotate relative to the final shaft 48A and to allow relative movement in the axial direction. The cam member 56 faces the final driven gear 55 side. And a damper spring 57 for biasing.

  A concave portion 58 is provided on a side surface of the final driven gear 55 facing the cam member 56, and an output side cam portion 60 that abuts on an input side cam portion 59 formed at the closed end of the concave portion 58 is provided on the cam member 56. It is formed. The damper spring 57 is a coil spring that surrounds the final shaft 48A. A retainer 61 that receives one end of the damper spring 57 is fixed to the final shaft 48A. It abuts on the cam member 56.

  According to the torque damper 53, although the final driven gear 55 and the cam member 56 are integrally rotated when a torque equal to or lower than a predetermined torque acts between the final driven gear 55 and the cam member 56, the engine of the motorcycle is used. When a torque exceeding a predetermined torque is applied between the final driven gear 55 and the cam member 56 during deceleration of the engine EA during braking or the like, a slip in the rotational direction occurs between the final driven gear 55 and the cam member 56, and The cam member 56 absorbs the excessive torque while moving to the side away from the final driven gear 55 against the spring force of the damper spring 57.

  Referring also to FIG. 4, the first clutch 41 accommodated in the first clutch chamber 31 so as to cut off / connect the transmission of the rotational power from the crankshaft 22 to the first main shaft 33 is the first clutch 41. A first clutch outer 62 that is rotatably supported on one end of the main shaft 33, a plurality of first friction plates 63, 63... Engaged with the first clutch outer 62, and the first main shaft 33. A plurality of first clutch inners 64 having cylindrical bosses 64a coupled so as not to rotate relative to each other and first friction plates 63, 63... Of the first and second friction plates 63, 63,... 65, 65,..., 65, 65,. The first receiver provided in The first clutch inner while having a pressing portion 67a on the outer periphery of the plate 66 and the first and second friction plates 63, 63... 65, 65. A first hydraulic pressure chamber 68 is formed between the first piston 67 and the first piston 67 that are spline-engaged with the first piston 67, and is fixed to the boss portion 64a. The first outer wall member 69 to be supported and the first canceller chamber 70 sandwiching the first piston 67 between the first hydraulic pressure chamber 68 and the first piston 67 are formed between the first piston 67 and the axial direction of the first outer wall member 69. The first inner wall member 71 fixed to the inner end and the spring force that urges the first piston 67 to the side that reduces the volume of the first hydraulic pressure chamber 68, that is, the side that separates the first piston 67 from the first pressure receiving plate 66. Thus, between the first piston 67 and the first inner wall member 71 And a first return spring 72 is interposed.

  A first fluid chamber 74 formed between the left cover 28 and a first lid member 73 coupled to the left cover 28 communicates with the first fluid pressure chamber 68 in a fluid-tight manner. When the high hydraulic pressure is applied to the first hydraulic pressure chamber 68, the first piston 67 presses the first and second friction plates 63, 63... 65, 65. The first clutch 41 connects between the first clutch outer 62 and the first clutch inner 64, that is, the first main shaft 33. The first canceller chamber 70 is supplied with low-pressure oil through a first lubricating oil passage 75 formed in the boss member 64a, the first main shaft 33, and the crankcase 21. The increase in the hydraulic pressure in the first hydraulic chamber 68 due to the centrifugal force accompanying the rotation of the one clutch 41 is cancelled.

  In addition, the bevel gear mechanism 49 is disposed outside the projection range of the first clutch 41 on the plane orthogonal to the axis of the first main shaft 33, and the direction is orthogonal to the axes of the first main shaft 33 and the final shaft 48A. , The bevel gear mechanism 49 is provided at one end of the final shaft 48A so that at least a part of the bevel gear mechanism 49 overlaps the first clutch 41.

  By the way, the rotational power from the crankshaft 22 is transmitted to the first main shaft 33 via the first primary reduction gear train 39 and the first clutch 41. The first primary reduction gear train 39 The first primary drive gear 76 is fixed to one end of the crankshaft 22, and the first primary driven gear 77 is engaged with the first primary drive gear 76 and arranged coaxially with the first main shaft 33. The first primary driven gear 77 is supported on the first main shaft 33 so as to be relatively rotatable, and is connected to the first clutch outer 62 via a first damper spring 78.

  The second clutch 42 housed in the second clutch chamber 32 is connected to the other end portion of the second main shaft 34 so that the transmission of the rotational power from the crankshaft 22 to the second main shaft 34 is disconnected and connected. A second clutch outer 82 that is rotatably supported, a plurality of third friction plates 83 that are engaged with the second clutch outer 82, and a cylinder that is coupled to the second main shaft 34 so as not to be relatively rotatable. And the like, and a plurality of fourth friction plates 85, 85,... That are alternately arranged with the third friction plates 83, 83, and engaged with the second clutch inner 84. , 85, 85,..., 85, 85,..., 85, 85..., Second pressure receiving plate 86 integrally provided with the second clutch inner 84. And alternately Of the third and fourth friction plates 83, 83,..., 85, 85,... A second hydraulic wall 88 is formed between the two pistons 87 and the second piston 87 and is fixed to the boss portion 84a, and a second outer wall member 89 that supports the axial sliding of the second piston 87; A second canceller chamber 90 is formed between the first piston 67 and the second piston 87 between the second hydraulic chamber 88 and the second piston 87 is fixed to the axially inner end of the second outer wall member 89. The second piston 87 and the second piston 87 so as to exert a spring force that urges the inner wall member 91 and the side of the first hydraulic pressure chamber 88 to reduce the volume, that is, the second piston 87 away from the second pressure receiving plate 86. A second return member interposed between the second inner wall members 91 And a 92.

  A second fluid chamber 94 formed between the right cover 29 and the second lid member 93 coupled to the right cover 29 communicates with the second fluid pressure chamber 88 in a fluid-tight manner. When the high hydraulic pressure is applied to the second hydraulic pressure chamber 88, the second piston 87 presses the third and fourth friction plates 83, 83... 85, 85. The second clutch 42 connects between the second clutch outer 82 and the second clutch inner 84, that is, the second main shaft 34. The second canceller chamber 90 is supplied with low-pressure oil through a second lubricating oil passage 95 formed in the boss member 84a, the second main shaft 34, and the crankcase 21. The hydraulic pressure increase in the second hydraulic pressure chamber 88 due to the centrifugal force accompanying the rotation of the two clutch 42 is cancelled.

  Rotational power from the crankshaft 22 is transmitted to the second main shaft 34 via a second primary reduction gear train 40 and a second clutch 42. The second primary reduction gear train 40 is The second primary drive gear 96 is fixed to the right end of the shaft 22, and the second primary driven gear 97 is meshed with the second primary drive gear 96 and arranged coaxially with the second main shaft 34. The second primary driven gear 97 is supported by the second main shaft 34 so as to be relatively rotatable, and is connected to the second clutch outer 82 via a second damper spring 98.

  In FIG. 5, the rotational power from the crankshaft 22 is transmitted to a generator 100 having a rotational axis parallel to the crankshaft 22, and the crankshaft 22 is rotated in parallel to the rotational axis of the generator 100. Rotational power from the starter motor 101 having an axis is input as starting power, and the generator 100 and the starter motor 101 are disposed obliquely in front of the crankshaft 22.

  The generator 100 includes a generator case 102 attached to the left side wall of the lower case half 21b of the crankcase 21, a rotor 104 provided on a rotary shaft 103 having an axis parallel to the crankshaft 22, and the power generation A stator 105 that surrounds the rotor 104 and is fixed to the generator case 102 while being accommodated in the machine case 102, and is on the same side as the first clutch 41 in the direction along the axis of the crankshaft 22. Be placed.

  The rotary shaft 103 is rotatably supported by the generator case 102 via a ball bearing 106 and is plunged into the crankcase 21, and the rotary shaft 103 rushes into the crankcase 21. A ball bearing 107 is interposed between the end portion and the crankcase 21.

  As shown in FIG. 3, a drive sprocket 108, which is a rotating member for ACG drive for transmitting rotational power to the rotating shaft 103 of the generator 100, is provided on the crankshaft 22, and the drive sprocket 108 is connected to the crankshaft. A part of the first primary reduction gear train 39 that transmits rotational power from the shaft 22 to the first main shaft 33 is formed and arranged axially outwardly from the first primary drive gear 76 that is fixed to the crankshaft 22. Is done.

  On the other hand, a driven sprocket 109 having a torque buffering mechanism 111 interposed between the rotary shaft 103 and the rotary shaft 103 is arranged coaxially with the rotary shaft 103 at a position corresponding to the drive sprocket 108 in the axial direction of the crankshaft 22. An endless chain 110 is wound around the drive sprocket 108 and the driven sprocket 109.

  Therefore, the rotational power of the crankshaft 22 is transmitted to the rotary shaft 103 via the drive sprocket 108, the chain 110, the driven sprocket 109, and the torque buffer mechanism 111.

  The motor case 112 of the starter motor 101 is attached to the crankcase 21 with its motor shaft 113 arranged in parallel with the rotating shaft 103, and a driven gear that meshes with a pinion 114 provided on the motor shaft 113. 115 is supported on the rotary shaft 103 so as to be relatively rotatable, and a one-way clutch 116 that allows only power transmission from the starter motor 101 to the rotary shaft 103 side between the driven gear 115 and the rotary shaft 103. It is installed.

  Next, the operation of the first embodiment will be described. The first clutch 41 for connecting / disconnecting the rotational power transmitted from the crankshaft 22 to the first main shaft 33 is provided at one axial end of the first main shaft 33. In the arranged power unit PA, a final shaft 48A to which rotational power from the counter shaft 43 can be transmitted is rotatably supported on the crankcase 21 with an axis parallel to the first main shaft 33, and the counter shaft 43 The bevel gear mechanism 49 that transmits the rotational power from the rear wheel WR, which is the driving wheel, is outside the projection range of the first clutch 41 on the plane orthogonal to the axis of the first main shaft 33 and the first main shaft The clamp of the final shaft 48A is disposed inward in the axial direction from one axial end portion of the 33. Since it is provided at one end protruding from the case 21, the first clutch 41 and the bevel gear mechanism 49 disposed at one axial end of the first main shaft 33 are arranged on the same side along the axial direction of the first main shaft 33. Even if the structure provided is adopted, the first clutch 41 and the bevel gear mechanism 49 do not overlap in the axial direction, and it is not necessary to house the first clutch 41 in a case separate from the crankcase 21. It is possible to reduce the size of the power unit PA in the axial direction of the first main shaft 33 while avoiding mutual interference between the one clutch 41 and the bevel gear mechanism 49 and reducing the number of parts.

  Further, since the bevel gear mechanism 49 is disposed axially outward from one axial end of the counter shaft 43, the bevel gear mechanism 49 and the counter shaft 43 are mutually connected even when the counter shaft 43 and the final shaft 48A are disposed close to each other. The power unit PA can be further reduced in size.

  Further, when viewed in a direction perpendicular to the axis of the first main shaft 33 and the final shaft 48A, at least a part of the bevel gear mechanism 49 overlaps the first clutch 41 so that the bevel gear mechanism 49 is connected to the final shaft 48A. Thus, the bevel gear mechanism 49 can be disposed close to the first clutch 41, and the amount of axial projection of the bevel gear mechanism 49 from the crankcase 21 can be suppressed.

  Further, a drive sprocket 108 for transmitting rotational power to the rotating shaft 103 of the generator 100 disposed on the same side as the first clutch 41 in the direction along the axis of the crankshaft 22 is provided from the crankshaft 22 to the first main shaft. A part of the first primary reduction gear train 39 that transmits rotational power to the shaft 33 is provided on the crankshaft 22 at an axially outer side than the first primary drive gear 76 that is fixed to the crankshaft 22. Therefore, the first primary driven gear 77 and the first clutch 41 provided on the first main shaft 33 are axially inward compared to the case where the drive sprocket 108 is disposed axially inward of the first primary drive gear 76. The axial length of the first main shaft 33 can be shortened to further reduce the size of the power unit PA. It is possible.

  The generator 100 and the starter motor 101 may be disposed between the front bank BF and the rear bank BR as shown by a chain line in FIG.

  As a second embodiment of the present invention, as shown in FIG. 6, a driving sprocket 108 which is an ACG driving rotating member constitutes a part of the first primary reduction gear train 39 as shown in FIG. The first primary drive gear 76 fixed to the crankshaft 22 may be provided on the crankshaft 22 inwardly in the axial direction, and as a third embodiment of the present invention, as shown in FIG. The drive sprocket 108 disposed axially inward of the first primary drive gear 76 fixed to the crankshaft 22 constitutes a part of the first primary reduction gear train 39 and is coaxial with the first main shaft 33. Alternatively, the first primary driven gear 77 disposed at the position may be integrally provided.

  As a fourth embodiment of the present invention, as shown in FIG. 8, the first clutch 41 (see the first embodiment) and the direction along the axis of the crankshaft 22 (see the first embodiment) and Rotational power from the crankshaft 22 (see the first embodiment) may be transmitted to the generator 118 arranged on the same side via the gear train 119 and the damper spring 120.

  A generator case 121 of the generator 118 is fixed to the crankcase 21, and a transmission shaft 123 that is coaxially coupled to the rotating shaft 122 of the generator 118 and is relatively non-rotatable is connected to the generator via a ball bearing 124. The case 121 is rotatably supported by the case 121, and is rotatably supported by a cover 125 attached to the crankcase 21 via a ball bearing 126.

  The gear train 119 includes a first primary drive gear 76 in the first primary reduction gear train 39, a first idle gear 127 meshing with the first primary drive gear 76, and a second idle gear meshing with the first idle gear 127. 128 and a driven gear 129 that meshes with the second idle gear 128 and is rotatably supported by the transmission shaft 123. The damper spring 120 is interposed between the driven gear 129 and the transmission shaft 123. The

  FIG. 9 shows a fifth embodiment of the present invention. The parts corresponding to the first to fourth embodiments are indicated by the same reference numerals, and the detailed description will be given. Omitted.

  Rotational power is transmitted to the rear wheel WR (refer to the first embodiment), which is a drive wheel, at one end of a final shaft 48B that is rotatably supported by the crankcase 21 via ball bearings 131 and 132. A drive sprocket 133 as output means is provided so as to be disposed outside the projection range of the first clutch 41 onto a plane orthogonal to the axis of the first main shaft 33. The drive sprocket 133 has an endless shape. The chain 134 is wound around.

  Thus, the drive sprocket 133 is disposed axially inward from one axial end of the first main shaft 33 and axially outward from one axial end of the counter shaft 43, and the crank of the final shaft 48B. It is provided at one end protruding from the case 21.

  In addition, the first primary driven gear 77 that constitutes a part of the first primary reduction gear train 39 that transmits rotational power from the crankshaft 22 to the first main shaft 33 and is coaxially linked and connected to the first main shaft 33 is: The drive sprocket 133 is disposed at an axially outer position in the direction along the first main shaft 33.

  Rotational power of the counter shaft 43 is transmitted to the final shaft 48B via a final gear train 135. The final gear train 135 includes a right side wall of the crankcase 21 and a second speed gear train. A driving gear 136 fixed to the countershaft 43 between G2 and a driven gear 137 fixed to the final shaft 48B so as to mesh with the driving gear 136.

  According to the fifth embodiment, the drive sprocket 133 that transmits the rotational power from the countershaft 43 to the rear wheel WR side that is the drive wheel is the first to the plane orthogonal to the axis of the first main shaft 33. Since it is provided at one end protruding from the crankcase 21 of the final shaft 48A while being disposed outside the projection range of the clutch 41 and axially inward from one axial end of the first main shaft 33, Even if the first clutch 41 and the driving sprocket 133 disposed at one axial end of the first main shaft 33 are disposed on the same side along the axial direction of the first main shaft 33, The clutch 41 and the drive sprocket 133 do not overlap in the axial direction, and the first clutch 41 is accommodated in a case different from the crankcase 21. Since there is no necessity, it is possible with avoiding mutual interference of the first clutch 41 and the drive sprocket 133 while achieving reduction in the number of components, reduce the size of the power unit PA in the axial direction of the first main shaft 33.

  Further, since the drive sprocket 133 is disposed axially outward from one axial end of the counter shaft 43, the drive sprocket 133 and the counter shaft 43 are mutually connected even when the counter shaft 43 and the final shaft 48A are disposed close to each other. The power unit PA can be further reduced in size.

  Further, a first primary driven gear 77 that constitutes a part of the first primary reduction gear train 39 and is coaxially linked and connected to the first main shaft 33 is more than the drive sprocket 133 in the direction along the first main shaft 33. Since the drive sprocket 133 is disposed at the axially outward position, the drive sprocket 133 can be disposed in a compact manner without projecting outward from the first primary driven gear 77 in the axial direction.

  FIG. 10 shows a sixth embodiment of the present invention. The parts corresponding to those of the first to fifth embodiments are indicated by the same reference numerals, and the detailed description is as follows. Omitted.

  Rotational power is transmitted to the rear wheel WR (refer to the first embodiment), which is a driving wheel, at one end portion of a final shaft 48C rotatably supported on the crankcase 21 via ball bearings 139 and 140. A drive sprocket 133 as output means is provided so as to be disposed outside the projection range of the first clutch 41 onto a plane orthogonal to the axis of the first main shaft 33. The drive sprocket 133 has an endless shape. The chain 134 is wound around.

  Thus, the drive sprocket 133 is disposed axially inward from one axial end of the first main shaft 33 and axially outward from one axial end of the counter shaft 43, and the crank of the final shaft 48C. It is provided at one end protruding from the case 21.

  In addition, the first primary driven gear 77 that constitutes a part of the first primary reduction gear train 39 that transmits rotational power from the crankshaft 22 to the first main shaft 33 and is coaxially linked and connected to the first main shaft 33 is: The drive sprocket 133 is disposed at an axially outer position in the direction along the first main shaft 33.

  Between the counter shaft 43 and the final shaft 48C, there are provided a plurality of final gear trains that can be alternatively established and have different gear ratios. In the sixth embodiment, A pair of first and second final gear trains 141 and 142 are provided between the counter shaft 43 and the final shaft 48C.

  The first final gear train 141 includes a first drive gear 143 fixed to the countershaft 43 and a first driven gear that is rotatably supported on the final shaft 48C so as to mesh with the first drive gear 143. 144, and the second final gear train 142 is supported on the final shaft 48C so as to be relatively rotatable so as to mesh with the second drive gear 145 fixed to the counter shaft 43 and the second drive gear 145. Second driven gear 146.

  Further, first and second shifters 147 and 148 corresponding to the first and second final gear trains 141 and 142 are mounted on the final shaft 48C so as not to rotate relative to each other and to move in the axial direction. Is engaged with the first driven gear 144, the rotational power is transmitted from the counter shaft 43 to the final shaft 48C via the first final gear train 141, and when the second shifter 148 is engaged with the second driven gear 146, the first driven gear 144 is engaged. Rotational power is transmitted from the counter shaft 43 to the final shaft 48C via the two final gear train 142.

  Moreover, the first and second shifters 147 and 148 can simultaneously establish the first and second final gear trains 141 and 142. When the first and second final gear trains 141 and 142 are simultaneously established, the first and second final gear trains 141 and 142 are simultaneously parked. It is possible to obtain a brake state.

  According to the sixth embodiment, the same effects as those of the fifth embodiment can be obtained, and a plurality of parts provided between the first and second main shafts 33 and 34 and the counter shaft 43 can be provided. The gear stages G1 to G6 and the first and second final gear trains 141 and 142 can increase the number of shift stages and increase the degree of freedom of the shift torque. In addition, since the parking brake state can be obtained using the first and second final gear trains 141 and 142, it is not necessary to provide a special parking brake mechanism, and the parking brake state is avoided while avoiding an increase in the number of parts. Can be obtained.

  A seventh embodiment of the present invention will be described with reference to FIGS. 11 to 13. First, in FIG. 11, the vehicle power unit PB includes a single-cylinder engine EB and an engine main body 151 of the engine EB. The engine body 151 has a built-in gear transmission T and is mounted on a motorcycle or the like. The engine body 151 is a crank as an engine case that rotatably supports a crankshaft 152 extending in the left-right direction of the vehicle. A cylinder body 154 having a case 153, a cylinder bore 159 in which the piston 158 is slidably fitted, and coupled to the crankcase 153, and a combustion chamber 160 facing the top of the piston 158 are provided between the cylinder body 154 and the cylinder body 154. A cylinder head 155 formed between and coupled to the cylinder body 154; And a head cover 156 coupled to the upper portion of the head 155, the lower portion of the crankcase 153 oil pan 157 is coupled.

  The crankcase 153 is formed by combining an upper case half 161 and a lower case half 162 that are integral with the cylinder body 154, and the crankshaft 1552 includes the upper case half 161 and the upper case half 161. The crankcase 153 is rotatably supported so that an extension line of an axial line is disposed on the mating surface 163 of the lower case half 162.

  An intake device 165 having a throttle valve 164 is connected to the rear side surface of the cylinder head 155, and an exhaust device 166 that extends rearward through the lower side of the engine body 1551 is connected to the front side surface of the cylinder head 155. Connected.

  Referring also to FIG. 12, the gear transmission T includes first and second main shafts 167 and 168 that are arranged coaxially with an axis parallel to the crankshaft 1552, and first and second A counter shaft 169 having an axis parallel to the main shafts 167, 168, and a plurality of shift stages provided between the first and second main shafts 167, 168 and the counter shaft 169 as selectively established. For example, the first to sixth speed gear trains G1, G2, G3, G4, G5, and G6 are included. The first main shaft 167, the second main shaft 168, and the counter shaft 169 are crankcases 153. It is supported rotatably.

  Thus, the first main shaft 167 passes through the left side wall of the lower case half 162 rotatably, and a ball bearing 171 is interposed between the first main shaft 167 and the left side wall. The second main shaft 168 passes through the right side wall of the lower case half 162 of the crankcase 153 in a rotatable manner, and a ball bearing 172 is interposed between the second main shaft 168 and the right side wall. The ball bearing 172 has a larger diameter than the ball bearing 171 interposed between the lower case half 162 of the crankcase 153 and the first main shaft 167.

  On the other hand, one end of the counter shaft 169 is rotatably supported on the left side wall of the lower case half 162 via a ball bearing 173, and the other end of the counter shaft 169 is the right side wall of the lower case half 162. Are supported rotatably via a needle bearing 174.

  Further, a final shaft 170 to which rotational power from the counter shaft 169 is transmitted is supported on the lower case half 162 so as to be rotatable about an axis parallel to the counter shaft 169. One end portion of the final shaft 170 penetrates the left side wall of the lower case half 162 rotatably, and a ball bearing 175 and an annular seal member 176 are interposed between the final shaft 170 and the left side wall. The other end of the final shaft 170 is rotatably supported on the right side wall of the lower case half 162 via a needle bearing 177.

  A driving sprocket 133 as an output member for transmitting rotational power to a driving wheel (rear wheel) (not shown) is provided at the protruding end of the final shaft 170 protruding from the left side wall of the lower case half 162. A chain 134 is wound around the drive sprocket 133.

  Referring also to FIG. 13, the rotation transmitted from the crankshaft 152 to the first and second main shafts 167 and 168 is provided at the opposite ends of the first and second main shafts 167 and 168. First and second clutches 181 and 182 for connecting / disconnecting power are disposed, and ends of the first and second main shafts 167 and 168 opposite to the first and second clutches 181 and 182 are relatively opposite to each other. They can be rotated and fitted and supported with each other.

  The second main shaft 168 includes a large-diameter portion 168a and a small-diameter portion 168b fitted to the first main shaft 167 that are coaxially and integrally connected to each other. The small-diameter portion 168b of the second main shaft 168 and A plurality of, for example, a pair of needle bearings 183 and 183 are interposed between the first main shafts 167.

  Between the first main shaft 167 and the counter shaft 169, second, fourth and sixth speed gear trains G2, G4, G6, which are even gear trains among the six gear trains, are alternatively selected. Between the large-diameter portion 168a of the second main shaft 168 and the counter shaft 169, the first, third and third gear trains which are odd-numbered gear trains among the six gear trains. The fifth speed gear trains G1, G3, G5 are provided so as to be alternatively established.

  In addition, second, fourth and sixth speed gear trains G2, G4 and G6 provided between the first main shaft 167 and the counter shaft 169, and a first main shaft provided between the second main shaft 168 and the counter shaft 169 are provided. The third and fifth speed gear trains G1, G3, G5 are arranged separately on both sides of the engine center C in the axial direction of the crankshaft 152.

  A ball bearing 171 interposed between the first main shaft 167 and the left side wall of the lower case half 162, and a ball bearing 172 interposed between the second main shaft 168 and the right side wall of the lower case half 162 Is arranged so that the gear trains G1 to G6 of 6 shift stages are sandwiched between them, and the end of the second main shaft 168 opposite to the second clutch 182, that is, the end of the small diameter portion 168b is The first main shaft 167 extends to a portion corresponding to the ball bearing 171 between the first main shaft 167 and the lower case half 162.

  A first clutch 181 for connecting / disconnecting transmission of rotational power from the crankshaft 152 to the first main shaft 167 includes a first clutch outer 184 that is rotatably supported on the left end of the first main shaft 167, A plurality of first friction plates 185, 185... Engaged with the first clutch outer 184, a first clutch inner 186 coupled to the first main shaft 167 in a relatively non-rotatable manner, and first friction plates 185, 185. Are alternately arranged and engaged with the first clutch inner 186, and the first and second friction plates 185, 185, ...; 187,187 alternately arranged. ... Of the first pressure receiving plate 188 provided integrally with the first clutch inner 186 so as to face the axially inner friction plate and the first clutch inner 186 can slide relative to each other. Of the first and second friction plates 185, 185,... 187, 187,. A first pressing member 189 provided integrally so that the first pressing portion 189a projects outward in the radial direction, and a first pressing member 189 attached to the side where the first pressing portion 189a is separated from the first pressure receiving plate 188. The first disengagement spring 190 interposed between the first clutch inner 186 and the first pressing member 189 and the first pressing member 189 are prevented from being separated from the first pressing member 189. A disk-shaped first transmission member 191 that is coaxially inserted into the member 189 and a spring force that urges the first transmission member 191 toward the opening end side of the first pressing member 189 to exhibit the first pressing member 189. And the first transmission member 19 A first push spring 56 provided between the first transmission member 191 and a first actuating member 193 disposed coaxially with the first transmission member 191 and coupled to the first transmission member 191 via a first release bearing 194; One actuating member 193 is driven in the axial direction by an actuator (not shown).

  In such a first clutch 181, when the actuator is in an inoperative state, the first pressing member 189 is biased toward the disengagement side by the first disengagement spring 190, so that the first clutch 181 transmits power. Is in a disconnected state. Next, when the actuator is actuated to actuate the first actuating member 193 in the axial direction, the driving force is transferred from the first release bearing 194 to the first pressing member 189 via the first transmission member 191 and the first push spring 192. The first pressing member 189 compresses the first disengagement spring 190 and presses the first and second friction plates 185, 185... 187, 187. The first clutch outer 184 and the first clutch inner 186 are connected by friction engagement.

  Thus, when the first push spring 192 is compressed according to the axial operation of the first actuating member 193 and the elastic force of the first push spring 192 exceeds the elastic force of the first disengagement spring 190, The first pressing member 189 is driven with a thrust according to the compression amount of the first push spring 192, and the clutch pressing force acts on the first and second friction plates 185, 185, 187, 187, and the clutch pressing force. The first clutch 181 is in a connected state with a clutch capacity corresponding to the above. That is, a linear relationship can be established between the position of the first actuating member 193 and the torque transmission capacity of the first clutch 181, and the torque transmission capacity of the first clutch 181 is controlled with high accuracy by controlling the operation of the actuator. It becomes possible to do.

  By the way, the rotational power from the crankshaft 152 is transmitted to the first main shaft 167 via the first primary reduction gear train 195 and the first clutch 181, and the first primary reduction gear train 195 A first primary drive gear 196 fixed to the left end of the crankshaft 152 and a first primary driven gear 197 that meshes with the first primary drive gear 196 and is arranged coaxially with the first main shaft 167. . The first primary driven gear 197 is disposed between the ball bearing 171 and the first clutch outer 184 of the first clutch 181 and is supported on the first main shaft 167 so as to be relatively rotatable. Connected to one clutch outer 184.

  Thus, the drive sprocket 133 is provided at one end portion of the final shaft 170 protruding from the crankcase 153. The drive sprocket 133 is first in a plane perpendicular to the axis of the first main shaft 167. It is arranged outside the projection range of the clutch 181 and axially inward from one axial end of the first main shaft 167, and is arranged axially outward from one axial end of the counter shaft 169. . Further, when viewed in a direction perpendicular to the axis of the first main shaft 167 and the final shaft 170, at least a part of the drive sprocket 133 overlaps the first clutch 181 so that the drive sprocket 133 is connected to the final shaft 170. Is provided at one end.

  In addition, a part of the first primary driven gear 197 that constitutes a part of the first primary reduction gear train 195 and is coaxially linked and connected to the first main shaft 167 is the axial direction of the first clutch 181 and the counter shaft 169. One end and the portion surrounded by the final shaft 170 are disposed.

  A second clutch 182 for connecting / disconnecting transmission of rotational power from the crankshaft 152 to the second main shaft 168 includes a second clutch outer 201 supported on the right end of the second main shaft 168 in a relatively rotatable manner, A plurality of third friction plates 202, 202... Engaged with the second clutch outer 201, a second clutch inner 203 coupled to the second main shaft 168 in a relatively non-rotatable manner, and the third friction plates 202, 202. ... and a plurality of fourth friction plates 204, 204 ... that are alternately arranged and engaged with the second clutch inner 203, and third and fourth friction plates 202, 202 ...; 204, 204 that are alternately arranged. ... Of the second pressure receiving plate 205 provided integrally with the second clutch inner 203 facing the axially inner friction plate and the second clutch inner 203 can slide relative to each other. .. Of the third and fourth friction plates 202, 202... 204, 204. The second pressing member 206 is integrally provided so that the second pressing portion 206a projects outward in the radial direction, and the second pressing member 206 is attached to the side where the second pressing portion 206a is separated from the second pressure receiving plate 205. The second engagement release spring 207 interposed between the second clutch inner 203 and the second pressing member 206 and the second pressing member 206 are prevented from being separated from the second pressing member 206. A disk-shaped second transmission member 208 that is coaxially inserted into the member 206, and a spring force that urges the second transmission member 208 toward the opening end side of the second pressing member 206 to exhibit the second pressing member 206 And the second transmission member 20 A second push spring 209 provided between the second transmission member 208 and a second actuating member 210 disposed coaxially with the second transmission member 208 and coupled to the second transmission member 208 via a second release bearing 211; 2 The actuating member 210 is driven in the axial direction by an actuator (not shown).

  Such a second clutch 182 is operated to be disconnected and connected in the same manner as the first clutch 181, and has a linear relationship between the position of the second operating member 210 and the torque transmission capacity of the second clutch 182. The torque transmission capacity of the second clutch 182 can be controlled with high accuracy by controlling the operation of the actuator.

  Rotational power from the crankshaft 152 is transmitted to the second main shaft 168 via the second primary reduction gear train 212 and the second clutch 182, and the second primary reduction gear train 212 is A second primary drive gear 213 fixed to the right end portion of the shaft 152 and a second primary driven gear 214 that meshes with the second primary drive gear 213 and is arranged coaxially with the second main shaft 168. The second primary driven gear 214 is supported on the second main shaft 168 so as to be relatively rotatable, and is connected to the second clutch outer 201 via the second damper rubber 215.

  A final gear train 216 that transmits rotational power from the counter shaft 169 to the final shaft 170 is provided between the counter shaft 169 and the final shaft 170. The final gear train 216 is connected to the counter shaft 169. A final drive gear 217 provided integrally and a final driven gear 218 that meshes with the final drive gear 217 and is provided on the final shaft 170 so as not to be relatively rotatable.

  Moreover, the final drive gear 217 is provided near one end of the counter shaft 169 on the drive sprocket 133 side, and in the seventh embodiment, the lower case half of the crankcase 153 is provided. The final drive gear 217 is integrally provided on the countershaft 169 between the ball bearing 173 interposed between the left side wall of the body 162 and one end of the countershaft 169 and the second speed gear train G2. .

  Next, the operation of the seventh embodiment will be described. The ends of the first and second main shafts 167 and 168 opposite to the first and second clutches 181 and 182 can be rotated relative to each other. Since it is fitted and supported, it is unnecessary to provide a bearing between the crankcase 153 and the first and second main shafts 167 and 168 on the opposite side to the first and second main shafts 167 and 168. The number of parts can be reduced, the overall axial length of the first and second main shafts 167 and 168 can be shortened, and the power unit PB for the vehicle in the axial direction of the first and second main shafts 167 and 168 can be reduced. Miniaturization can be achieved.

  The second, fourth and sixth speed gear trains G2, G4 and G6 provided between the first main shaft 167 and the counter shaft 169, and the first and second gear trains provided between the second main shaft 168 and the counter shaft 169, respectively. Since the third and fifth gear trains G1, G3, and G5 are arranged separately on both sides of the engine center C in the axial direction of the crankshaft 152, the weight balance in the axial direction of the crankshaft 152 is good. Can be.

  Further, the second main shaft 168 is fitted to the first main shaft 167 so as to be relatively rotatable, and a ball bearing 171 interposed between the first main shaft 167 and the crankcase 163, and the second main shaft 168 and the crankcase 153. A ball bearing 172 interposed therebetween is disposed at a position between which the first to sixth speed gear trains G1 to G6 are sandwiched, and is an end opposite to the second clutch 182 of the second main shaft 168. Since the portion extends to the portion corresponding to the ball bearing 171 in the first main shaft 167, the end of the second main shaft 168 opposite to the second clutch 182 and the first clutch of the first main shaft 167 The first and second main shafts 167 and 168 while stably supporting the end portions on the opposite side to 181 with each other. By shortening the entire axial length, it is possible to further reduce the size of the power unit PB vehicle in first and second axial direction of the main shaft 167, 168.

  In addition, since the second main shaft 168 has a large-diameter portion 168a and a small-diameter portion 168b fitted to the first main shaft 167, the first main shaft 167 has a large diameter. Can be avoided. In addition, since the needle bearings 183 are interposed between the small diameter portion 168b of the second main shaft 168 and the first main shaft 167, the wear of the small diameter portion 168b is prevented and the first main shaft 167 and the second main shaft 168 are prevented from being worn. Mutual support is possible, and the diameter of the first main shaft 167 can be reduced as compared with the case where a ball bearing is interposed between the small diameter portion 168 b and the first main shaft 167.

  In addition, the drive sprocket 133 that transmits the rotational power from the counter shaft 169 to the rear wheel WR side has an axis parallel to the first main shaft 167 so that the rotational power from the counter shaft 169 is transmitted. 153 provided at one end of the final shaft 170 that is rotatably supported by the crankcase 153 and is projected outward from the projection range of the first clutch 181 on a plane orthogonal to the axis of the first main shaft 167 Since the first main shaft 167 is disposed inward in the axial direction relative to one axial end portion of the first main shaft 167, the first clutch 181 and the drive sprocket 133 disposed at one axial end portion of the first main shaft 167 are the first main shaft. Even if the structure arranged on the same side along the axial direction of the shaft 167 is employed, the first clutch 18 And the drive sprocket 133 does not overlap in the axial direction, and the first clutch 181 does not need to be housed in a case separate from the crankcase 153, thereby avoiding mutual interference between the first clutch 181 and the drive sprocket 133. The power unit PB can be downsized in the axial direction of the first main shaft 167 while reducing the number of parts.

  Further, since the drive sprocket 133 is disposed axially outward from one axial end of the countershaft 169, the drive sprocket 133 and the countershaft 169 are mutually connected even when the countershaft 169 and the final shaft 170 are disposed close to each other. There is no interference, and the power unit PB can be further downsized.

  The first primary driven gear 197 is a part of a first primary reduction gear train 195 that transmits rotational power from the crankshaft 152 to the first main shaft 167 and is coaxially linked and connected to the first main shaft 167. A part of the engine EB is disposed at a portion surrounded by the first clutch 181, one axial end portion of the counter shaft 169 and the final shaft 170, thereby avoiding an increase in the size of the engine EB in the axial direction of the crankshaft 152. Thus, the first primary driven gear 197 can be arranged.

  Further, when viewed in a direction perpendicular to the axis of the first main shaft 167 and the final shaft 170, at least a part of the drive sprocket 133 overlaps the first clutch 181 so that the drive sprocket 133 is connected to the final shaft 170. Therefore, the amount of drive sprocket 133 protruding from the crankcase 153 in the axial direction can be suppressed while the drive sprocket 133 is disposed close to the first clutch 181.

  Further, a final drive gear 217 constituting a part of a final gear train 216 that transmits rotational power from the counter shaft 169 to the final shaft 170 is closer to one end of the counter shaft 169 on the drive sprocket 133 side. Therefore, the axial length of the final shaft 170 can be minimized and the weight can be reduced.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

  For example, in the above-described embodiments, the clutches 41, 42; 181 and 182 are provided at the opposite ends of the first and second main shafts 33 and 34; 167 and 168 arranged coaxially. Although the power units PA and PB have been described, the present invention is not limited to the clutch interposed between the crankshaft and the main shaft, and the bevel gear mechanism 49 and drive sprocket provided at one end of the final shaft having an axis parallel to the main shaft. The output means such as 133 can be widely implemented with respect to the power unit disposed on the same side in the axial direction of the main shaft.

21, 153... Crank case 22, which is an engine case, 152, crankshafts 33, 167, first main shafts 39, 195, which are main shafts, first primary reduction, which is a primary reduction gear train Gear trains 41, 181 ... first clutch 43, 169, which is a clutch, counter shaft 47 ... first primary driven gears 48A, 48B, 48C, 170, which are primary driven gears ... final shaft 49 ... Bevel gear mechanism 76 as an output means ... First primary drive gear 100 as a primary drive gear ... Generator 103 ... Rotating shaft 108 ... Drive sprocket 133 as a rotation member for ACG drive Output Drive sprockets 141, 142, 216 as a means Final gear trains 147, 148,. The first primary driven gear is a shifter 197 ... primary driven gear 217 ... final drive gear G1, G2, G3, G4, G5, G6 ··· rear wheel is a gear train WR ... driving wheel

Claims (9)

  A crankshaft (22,152) extending in the left-right direction of the vehicle, a main shaft (33,167) having an axis parallel to the crankshaft (22,152), and an axis parallel to the main shaft (33,167) The counter shaft (43, 169) having a shaft is rotatably supported by the engine case (21, 153), and is selectively established between the main shaft (33, 167) and the counter shaft (43, 169). A plurality of gear stages (G1, G2, G3, G4, G5, G6), and output means (49) for transmitting the rotational power from the counter shaft (43, 169) to the drive wheel (WR) side. 133) is arranged outside the engine case (21, 153) on one end side along the axial direction of the main shaft (33, 167), A clutch (41,181) for connecting / disconnecting rotational power transmitted from the crankshaft (22,152) to the main shaft (33,167) is disposed at one axial end of the main shaft (33,167). In the vehicle power unit, the final shaft (48A, 48B, 48C; 170) to which the rotational power from the counter shaft (43, 169) can be transmitted has an axis parallel to the main shaft (33, 167). The engine shaft (21, 153) is rotatably supported by the engine case (21, 153) and is outside the projection range of the clutch (41, 181) onto a plane perpendicular to the axis of the main shaft (33, 167). The output means (49, 133) disposed inward in the axial direction from one axial end of (33, 167) The final shaft (48a through 48c; 170) said power unit, characterized in that provided at one end portion protruding from the engine case (21,153) of.   The vehicle power unit according to claim 1, wherein the output means (49, 133) is arranged on an axially outer side than one axial end of the counter shaft (43, 169).   A primary driven gear (105) that constitutes a part of a primary reduction gear train (195) that transmits rotational power from the crankshaft (152) to the main shaft (167) and is linked and connected coaxially to the main shaft (167). A part of 197) is disposed in a portion surrounded by the clutch (181), one axial end of the counter shaft (169) and the final shaft (170). Vehicle power unit.   When viewed in a direction perpendicular to the axes of the main shaft (167) and the final shaft (170), at least a part of the output means (133) overlaps the clutch (181). 133. The vehicle power unit according to claim 1, wherein 133) is provided at one end of the final shaft (170).   A final drive gear (217) that constitutes a part of a final gear train (216) that transmits rotational power from the counter shaft (169) to the final shaft (170) is provided at both ends of the counter shaft (169). The vehicle power unit according to any one of claims 1 to 4, wherein the vehicle power unit is provided near one end on the output means (133) side.   A primary driven gear (which constitutes a part of a primary reduction gear train (39) for transmitting rotational power from the crankshaft (22) to the main shaft (33) and is coaxially linked and connected to the main shaft (33). The vehicle power unit according to claim 1 or 2, wherein 47) is disposed at an axially outer position than the output means (133) in a direction along the axis of the main shaft (33).   The counter shaft (43) and the final shaft (48C) are provided with a plurality of final gear trains (141, 142) that can be alternatively established and have different gear ratios. The power unit for vehicles in any one of Claims 1-6.   A plurality of shifters (147, 148) individually corresponding to the plurality of final gear trains (141, 142) can simultaneously establish the plurality of final gear trains (141, 142) to obtain a parking brake state. The vehicle power unit according to claim 7, wherein the vehicle power unit is mounted on the final shaft (48C).   ACG driving rotating member (108) for transmitting rotational power to the rotating shaft (103) of the generator (100) arranged on the same side as the clutch (41) in the direction along the axis of the crankshaft (22). ) Constitutes a part of a primary reduction gear train (39) for transmitting rotational power from the crankshaft (22) to the main shaft (33) and is fixed to the crankshaft (22). The vehicular power unit according to any one of claims 1 to 8, wherein the vehicular power unit is provided on the crankshaft (22) at an axially outer side than 76).

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