JP2008202628A - Transmission and engine unit equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission capable of enhancing workability when carrying out maintenance besides avoiding an enlargement of an engine unit, and to provide an engine unit equipped with the same. <P>SOLUTION: A transmission equipped with a continuously variable transmission mechanism 17 and an accommodation case (transmission case) 8b for accommodating the continuously variable transmission mechanism 17, keeps in the accommodation case 8b a shift state conversion mechanism 54 for changing a shift state by the continuously variable transmission mechanism 17. A pivotal support member 75 for supporting bearings 72b, 73b, 74b of shafts 61, 62, 63 forming the shift state conversion mechanism 54 is constituted by a member different from a case member (a case body) 8g forming the accommodation case 8b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a transmission including a continuously variable transmission mechanism and a storage case that stores the continuously variable transmission mechanism, and an engine unit including the transmission.

  For example, a scooter type motorcycle generally has a structure in which a unit swing type engine unit in which an engine body and a housing case housing a V-belt type continuously variable transmission mechanism are integrated is supported by a body frame so as to be swingable up and down. Is.

  In the above engine unit, the belt winding diameter of the drive pulley of the continuously variable transmission mechanism is variably controlled by the drive motor in accordance with the engine speed, the vehicle speed, etc. so that the gear ratio according to the operating state of the engine can be obtained. There may be a shift state conversion mechanism.

  As such a shift state conversion mechanism, a mechanism is proposed in which the rotation of the drive motor is converted into the axial movement of the movable pulley of the drive pulley via a plurality of reduction gear shafts (for example, Patent Document 1). reference).

In this case, the shift state conversion mechanism is housed in a separate conversion mechanism housing chamber provided to communicate with the belt chamber of the housing case, or the respective reduction gear shafts are case bodies constituting the housing case. In addition, a configuration that supports the case main body with a case cover that is detachably attached to the case main body is conceivable.
JP 2000-111331 A

  By the way, in the case of a configuration in which a conversion mechanism accommodation chamber separate from the above accommodation case is provided, there is a problem that the transmission, and thus the engine unit, is enlarged.

  Further, in the case of a configuration in which each reduction gear shaft is supported by the case body and the case cover, for example, when performing maintenance including replacement of the V belt, if the case cover is removed, the reduction gear shaft is in a cantilever state. There is a problem that workability is low.

  The present invention has been made in view of the above-described conventional situation, and provides a transmission device that can avoid an increase in size of the engine unit and can improve workability during maintenance, and an engine unit including the transmission device. It is aimed at that.

  The present invention is a transmission apparatus including a continuously variable transmission mechanism and a storage case that houses the continuously variable transmission mechanism, and a shift state conversion that changes a shift state by the continuously variable transmission mechanism in the storage case. The mechanism is arranged, and the shaft support member that supports the shaft that is one of the constituent members of the speed change state conversion mechanism is configured as a member different from the case member that constitutes the housing case.

  According to the transmission according to the present invention, since the shift state conversion mechanism is arranged in the housing case, it is possible to avoid an increase in the size of the transmission as in the case of providing a separate shift state conversion mechanism housing chamber.

  In addition, since the shaft support member that supports one of the constituent members of the shift state conversion mechanism is configured as a member different from the case member that configures the housing case, when the maintenance of the continuously variable transmission mechanism is performed, it is Even when the case member is removed, the shaft of the speed change state conversion mechanism is not in a cantilever state, and a reduction in workability can be avoided.

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

  1 to 12 are views for explaining an engine unit including a transmission according to an embodiment of the present invention. In the present embodiment, an engine unit mounted on a motorcycle will be described as an example. In the description of this embodiment, the terms front and rear and left and right mean front and rear and left and right when viewed in a seated state.

  In the figure, reference numeral 1 denotes a scooter type motorcycle. The motorcycle 1 is pivotally supported by an underbone type body frame 2 and a head pipe 3 positioned at the front end of the body frame 2 so as to be steerable left and right. A front wheel 4 is disposed at a lower end portion, and a steering handle is disposed at an upper end portion. 5, a front fork 6, a unit swing type engine unit 8 that is supported by the body frame 2 so as to swing up and down, and a rear wheel 7 is disposed at the rear end, and an engine unit 8 of the body frame 2. And a saddle-type seat 9 for two persons mounted on the upper side of the vehicle.

  The front side of the front fork 6 is covered with a front cover 11, the rear side is covered with a leg shield 12, and the lower periphery of the seat 9 is covered with a side cover 13. A low-floor footboard (not shown) is disposed between the leg shield 12 and the side cover 13.

  The vehicle body frame 2 extends rearward and downward from the head pipe 3 while expanding outward in the vehicle width direction, and extends from the lower end to the rear substantially horizontally. Left and right seat rails 21 and 21 that extend obliquely upward rearward from the middle part of the tube 20 and extend substantially horizontally rearward from the rear end, and vertically extend from the rear ends of the left and right down tubes 20, The upper end portion includes left and right engine suspension frames 22 and 22 connected to the left and right seat rails 21.

  The vehicle body frame 2 extends rearward from the head pipe 3 in a substantially straight line, and rear end portions of the left and right upper tubes 24 and 24 connected to the left and right seat rails 21 and the left and right The left and right seat stays 25, 25 that connect the right engine suspension frames 22, 22 and the seat rail 21 and the vicinity of the connection portion of the engine suspension frame 22 of the left and right seat rails 25 in the vehicle width direction. And a cross member 23 to be connected.

  A rear suspension 10 is interposed between the cross member 23 and the engine unit 8. A storage box 33 is disposed below the seat 9 of the body frame 2, a fuel tank 30 is disposed on the front side of the storage box 33, and a radiator 31 is disposed below the fuel tank 30.

  The engine unit 8 is formed integrally with the engine main body 8a that generates output, a crankshaft (output shaft) 18 that outputs the output, and the engine main body 8a, and accommodates a V-belt type continuously variable transmission mechanism 17. A transmission case (accommodating case) 8b having a belt chamber a disposed therein.

  The engine main body 8a is a water-cooled four-cycle single-cylinder engine mounted with the cylinder axis A oriented substantially horizontally. 19 is coupled to a cylinder block 8d slidably accommodated, and a cylinder head 8e having a spark plug 16, intake and exhaust camshafts (not shown) disposed on the front mating surface of the cylinder block 8d is coupled, It has a structure in which a head cover 8f is attached to the cylinder head 8e. The piston 19 is connected to the crankshaft 18 via a connecting rod 15.

  An intake pipe 37 communicating with the intake port is connected to the upper wall surface of the cylinder head 8e. A fuel injection valve 38 is mounted on the downstream end of the intake pipe 37, and a throttle valve 39 is disposed on the upstream side of the fuel injection valve 38 in the intake pipe 37. The upstream end of the intake pipe 37 is connected to an air cleaner 36 disposed and fixed on the upper wall surface of the transmission case 8b.

  A pair of left and right suspension arm portions 8j and 8j are integrally formed on the bottom wall of the crankcase 8c of the engine body 8a so as to protrude forward. Also, left and right pivot members 47 and 47 are fixed in the vicinity of the connecting portion of the down tube 20 of the left and right engine suspension frames 22 and 22.

  The engine unit 8 has left and right suspension arm portions 8j and 8j directly supported by the left and right engine suspension frames 22 of the vehicle body frame 2 via the pivot member 47, and can swing up and down. Although not shown, the left and right pivot members 47 have an elastic member such as rubber fixed between the outer cylinder fixed to the engine suspension frame 22 and the inner cylinder into which the pivot shaft 51 is inserted. Has the structure. The left and right suspension arm portions 8j are rotatably supported on the pivot shaft 51 via bearings (see FIG. 2).

  The V-belt type continuously variable transmission mechanism 17 includes a drive pulley 40 mounted on the left end 18a in the axial direction of the crankshaft 18 protruding into the transmission case 8b, and a follower disposed at the rear end of the transmission case 8b. It has a structure in which a V-belt 42 is wound around a pulley 41.

  The drive pulley 40 is a cylindrical drive shaft member 43 that is spline-fitted to rotate with the crankshaft 18, and is mounted on the drive shaft member 43 so as to be movable in the axial direction and to rotate with the drive shaft member 43. The movable sheave 40 a is fixed to the left end portion 18 a of the crankshaft 18 so as to be immovable in the axial direction by a lock nut 44, and rotates with the crankshaft 18.

  The driven pulley 41 is a cylindrical driven shaft member 46 that is rotatably mounted on a rotating shaft 44 that is pivotally supported by the transmission case 8b. The driven pulley 41 rotates together with the driven shaft member 46 so as not to move in the axial direction. A fixed sheave 41b that is fixed, a movable sheave 41a that is mounted on the driven shaft member 46 so as to be movable in the axial direction and rotates together with the fixed sheave 41b, and the driven shaft member 46 and the rotating shaft 44 are interposed between the driven sheave 41b and the rotating shaft 44. And a centrifugal clutch 60 provided. When the rotational speed of the driven pulley 41 increases, the clutch shoe 66 of the centrifugal clutch 60 comes into contact with the clutch drum 62 due to the centrifugal force, whereby the rotation of the driven pulley 41 is transmitted to the rotating shaft 44.

  The right end 44a of the rotating shaft 44 is inserted into a gear chamber c formed independently of the belt chamber a of the transmission case 8b, and an intermediate reduction shaft 48 and a rear wheel shaft are inserted into the gear chamber c. 7 a is arranged in parallel with the rotation shaft 44. A right end 7b of the rear wheel shaft 7a protrudes inward in the vehicle width direction from the transmission case 8b, and the rear wheel 7 is mounted on the right end 7b.

  The transmission case 8b is integrally formed so as to extend rearward after the left side wall 8n of the crankcase 8c, has a hole 8c 'through which the crankshaft 18 passes, and substantially accommodates the continuously variable transmission mechanism 17. A case main body 8g to be supported, and a case cover (lid member) 8h that is detachably bolted and fixed to a left side joint surface 8i of the case main body 8g.

  A cooling air introduction duct 27 having a cooling air introduction port 27a that opens to the front of the vehicle is detachably attached to the outer front portion of the case cover 8h.

  A plurality of cooling air inflow openings 8m are formed at predetermined intervals around the crankshaft 18 at a portion facing the drive pulley 40 of the case cover 8h, and cooling air is supplied to the upstream side of the cooling air inflow opening 8m. A filter 28 for filtering is detachably mounted. The traveling wind that has flowed in from the cooling air inlet 27a is introduced into the belt chamber a through the filter 28 from the cooling air inlet 8m.

  At the front end portion of the transmission case 8b, a winding diameter control chamber b is formed to bulge so as to extend obliquely upward in the front direction following the belt chamber a.

  When viewed from the side, the winding diameter control chamber b extends so as to substantially overlap the left side wall of the cylinder block 8d in the vehicle width direction, and is formed to extend forward following the left side wall 8n of the crankcase 8c. The right extension wall 8p and the left extension wall 8q formed to extend forward following the front edge of the case cover 8h.

  In the winding diameter control chamber b, a shift state conversion mechanism 54 for changing the shift state by the continuously variable transmission mechanism 17 is disposed.

  The transmission state conversion mechanism 54 transmits the rotation of the drive motor 55 to the reciprocating gear 56, and converts the rotation of the reciprocating gear 56 into the axial movement of the movable sheave 40a of the drive pulley 40. The belt winding diameter is automatically variably controlled between the low L and the top T. The drive motor 55 is driven and controlled by a controller (not shown) based on the engine speed, the vehicle speed, or the like, or based on an instruction from the driver.

  The transmission state conversion mechanism 54 includes a rotation transmission gear portion 57 that transmits the rotation of the drive motor 55 to the reciprocating gear 56, and an axial movement conversion that converts the rotation of the reciprocating gear 56 into the axial movement of the movable sheave 40a. Part 58.

  The rotation transmission gear portion 57 is disposed in the winding diameter control chamber b so as to be close to the drive pulley 40, and the axial movement conversion portion 58 is disposed between the drive pulley 40 in the belt chamber a and the left side wall 8n. Are arranged around the crankshaft 18.

  The drive motor 55 is disposed in front of the upper surface of the crankcase 8c so as to be positioned above the crankshaft 18 and in parallel with the crankshaft 18, and the right extension wall 8p of the right extension wall 8p forming the winding diameter control chamber b. It is fixed to the inner side in the vehicle width direction. The rotation shaft 55a of the drive motor 55 passes through the right extension wall 8p and protrudes into the winding diameter control chamber b.

  The rotation transmission gear portion 57 includes first and second transmission shafts 61 and 62 that transmit the rotation of the drive motor 55 to the reciprocating gear 56, and a detection shaft 63 that detects the rotation state of the drive motor 55.

  The first and second transmission shafts 61 and 62 and the detection shaft 63 are arranged in parallel with the crankshaft 18. When viewed from the side of the vehicle, the detection shaft 63 is located at the front end of the winding diameter control chamber b, the first transmission shaft 61 is located behind the detection shaft 63, and the second transmission shaft 62 is located obliquely below the rear. The rotating shaft 55a is located behind the first transmission shaft 61.

  The first transmission shaft 61 includes a large reduction gear 61a that meshes with the output gear 55a of the drive motor 55, and a small reduction gear 61b.

  The second transmission shaft 62 includes a slide gear 62a that meshes with both the reduction small gear 61b and the reciprocating gear 56, and a sensor gear 62b having a smaller diameter than the slide gear 62a.

  The detection shaft 63 includes a detection shaft drive gear 63a that meshes with the sensor gear 62b, and a rotation speed detection gear 63b. The input gear 64a of the rotational speed sensor 64 is engaged with the rotational speed detection gear 63b. The rotational speed sensor 64 detects the axial position of the movable sheave 40a from the rotational state of the drive motor 55, and in turn detects the winding diameter position of the V-belt 42.

  The axial movement conversion unit 58 is supported by a slide cylinder 65 mounted to rotate together with the movable sheave 40a and to move in the axial direction, and to the slide cylinder 65 via a bearing 66 so as to be relatively rotatable. And a movable-side feed screw member 67 fixed to the reciprocating gear 56, and a fixed-side feed screw member 68 that meshes with the movable-side feed screw member 67.

  The fixed-side feed screw member 68 is non-rotatably supported by a support member 69 that is bolted to the case body 8g. A centering bearing 71 is interposed between the support member 69 and a bearing support member 70 fixed to the crankshaft 18 so as to rotate together.

  When the engine speed and the vehicle speed increase with the accelerator opening operation of the rider, the rotation of the drive motor 55 is controlled so that the belt winding diameter is set in advance according to the engine speed and the vehicle speed. The rotation of the rotation shaft 55 a of the drive motor 55 is transmitted from the first and second transmission shafts 61 and 62 to the reciprocating gear 56, and when the reciprocating gear 56 rotates, the movable-side feed screw member 67 is driven together with the reciprocating gear 56. It moves in the axial direction by a distance corresponding to the rotation amount of the motor 55. Along with this, the movable sheave 40a moves a predetermined amount to the top side, and the drive pulley 40 has the belt winding diameter set as described above.

  The right end portions of the first and second transmission shafts 61 and 62 and the detection shaft 63 located on the case body 8g side are respectively extended by the right extension wall 8p of the case body 8g through the right bearings 72a, 73a, and 74a. The left end portion that is supported and located on the case cover 8h side is supported by a shaft support member 75 via bearings 72b, 73b, and 74b, respectively.

  The shaft support member 75 is disposed inside the case cover 8h so as to cover the right extension wall 8p of the case body 8g from the outside in the vehicle width direction, and forms the winding diameter control chamber b with the right extension wall 8p. ing.

  The shaft support member 75 is detachably attached to the inner side of the left joint surface 8i of the right extension wall 8p by a plurality of bolts 76, and is arranged so as to be exposed outward when the case cover 8h is removed. Has been.

  The mounting mating surface 75a of the shaft support member 75 is offset toward the engine main body 8a side on the inner side in the vehicle width direction from the left mating surface 8i that is the mounting surface of the case cover 8h of the case main body 8g (see FIG. 5). .

  The rear edge portion 75d of the shaft support member 75 is formed in an arc shape that is close to the front edge portion of the drive pulley 40, and the upper and lower portions of the rear edge portion 75d are provided on the case body 8g side and the case cover 8h side. A communication part, specifically, an upper opening 75b and a lower opening 75c are formed.

  The upper and lower openings 75b and 75c are formed so that the case cover 8h side and the case body 8g side of the transmission case 8b communicate with each other in the vehicle width direction. It is formed so as to be guided from the 40 side to the axial direction movement converting portion 58 side.

  Upper and lower ribs 75e and 75f are formed at the peripheral portions of the upper and lower openings 75b and 75c so as to extend in the communication direction (vehicle width direction). The upper rib 75e and the lower rib 75f extend along the edge of the rear edge 75 and form a continuous surface. In this way, the upper and lower openings 75b and 75c constitute a part of the cooling air passage that guides the cooling air C from the case cover 8h side to the case body 8g side.

  In addition, the communicating part in the present invention is not limited to the above-described opening, and may be a notch, for example, as long as it functions to guide the cooling air from the case cover 8h side to the case body 8g side.

  On the outer surface of the fixed sheave 40b of the drive pulley 40 and the inner surface of the movable sheave 40a, there are formed a large number of arcuate air blowing blades 40d and 40e extending in the radial direction at predetermined intervals in the circumferential direction. Yes.

  The cooling air C that has flowed in through the cooling air introduction duct 27 is sucked by the air blowing blades 40d of the fixed sheave 40b and is introduced into the belt chamber a through the filter 28 from the cooling air inflow opening 8m. A part of the cooling air C introduced into the belt chamber a is blown forward of the driving pulley 40 by the rotation of the fixed sheave 40b in the direction indicated by the arrow r in FIG. It is guided to the inside of the movable sheave 40a by the upper and lower openings 75b and 75c, and is supplied to the axial movement converting portion 58 by the respective air blowing blades 40e of the movable sheave 40a. The cooling air C that has passed through the axial movement conversion portion 58 flows backward in the belt chamber a, cools the V belt 42 and the driven pulley 41, and forms cooling air discharge holes formed at the rear end of the transmission case 8b. It is discharged outside (not shown).

  According to the present embodiment, since the transmission state conversion mechanism 54 that variably controls the belt winding diameter is disposed in the transmission case 8b, the transmission state conversion mechanism 54 can be made compact by effectively utilizing the space around the transmission case 8b. The engine unit 8 can be prevented from being enlarged.

  That is, at the front end of the transmission case 8b, a winding diameter control chamber b is formed to bulge so as to extend obliquely upward in front of the belt chamber a, and the shift state conversion mechanism 54 is accommodated in the winding diameter control chamber b. Since the winding diameter control chamber b is arranged so as to overlap the left side wall of the cylinder block 8d in the vehicle width direction, the shift state conversion mechanism 54 can be arranged by effectively utilizing the empty space on the left side of the cylinder block 8d.

  In the present embodiment, the right end portions of the first and second transmission shafts 61 and 62 and the detection shaft 63 constituting the shift state conversion mechanism 54 are supported by the case body 8g, and the left end portion is formed of a member separate from the transmission case 8b. Since it is supported by the shaft support member 75, when the case cover 8h is removed and maintenance of the V-belt 42 of the continuously variable transmission mechanism 17 is performed, the transmission shafts 61 and 62 and the detection shaft 63 are not cantilevered. Workability can be improved. Further, since the shaft support member 75 is detachably attached to the case body 8g, the maintenance of the shift state conversion mechanism 54 can be easily performed by removing the shaft support member 75.

  In the present embodiment, since the shaft support member 75 is arranged so that the shaft support member 75 is exposed to the outside when the case cover 8h is removed, the attaching / detaching operation of the shaft support member 75 can be facilitated.

  In this embodiment, the upper and lower openings 75b and 75c are formed in the shaft support member 75 so that the case cover 8h side and the case body 8g side communicate with each other in the vehicle width direction. It functions as a cooling air passage that guides the wind C from the case cover 8h side to the case body 8g side, and the cooling performance of the continuously variable transmission mechanism 17 and the transmission state conversion mechanism 54 can be enhanced.

  In the present embodiment, since the upper and lower ribs 75e and 75f extending in the vehicle width direction are formed at the peripheral portions of the upper and lower openings 75b and 75c, the rigidity of the upper and lower openings 75b and 75c can be increased. The cooling air C can be reliably guided to the axial movement conversion unit 58 including the drive pulley 40, and the cooling performance can be improved from this point.

  In this embodiment, the shift state conversion mechanism 54 is disposed in the vicinity of the drive pulley 40, and the cooling air C sucked by the rotation of the drive pulley 40 is moved to the case body 8g side through the upper and lower openings 75b and 75c. Since it introduce | transduced, the cooling property of the drive pulley 40 and the axial direction movement conversion part 58 can be improved further.

  In the above-described embodiment, the transmission device employed in the motorcycle engine unit has been described. However, the transmission device of the present invention is not limited to the motorcycle engine unit, and the transmission device employed in any machine. Applicable to the device.

1 is a side view of a motorcycle including an engine unit according to an embodiment of the present invention. It is a side view of the engine unit. It is a side view of the transmission case of the engine unit. It is a cross-sectional top view of the V belt type continuously variable transmission mechanism accommodated in the transmission case. It is a cross-sectional top view of the transmission state conversion mechanism accommodated and arrange | positioned in the said transmission case. It is a side view of the front part of the said transmission case. It is a side view of the front part of the said transmission case. It is sectional drawing of the said transmission state conversion mechanism. It is sectional drawing of the said transmission state conversion mechanism. It is a side view of the shaft support member of the shift state conversion mechanism. It is sectional drawing (XI-XI sectional view taken on the line of FIG. 10) of the said shaft support member. It is sectional drawing (XII-XII sectional view taken on the line of FIG. 10) of the said shaft support member.

Explanation of symbols

7 Rear wheel 8 Engine unit 8a Engine body 8b Transmission case (storage case)
8c 'Output shaft through hole 8g Case body 8h Case cover (lid member)
17 V-belt type continuously variable transmission mechanism 18 Crankshaft (output shaft)
40 Drive pulleys 40d, 40e Blower blade 54 Shift state conversion mechanism 61, 62 Transmission shaft 63 Detection shaft 72a, 73a, 74a Bearing 72b, 73b, 74b Bearing 75 Shaft support member 75b, 75c Opening (communication portion)
75e, 75f Rib C Cooling air

Claims (12)

A transmission comprising a continuously variable transmission mechanism and a storage case for storing the continuously variable transmission mechanism,
A shift state conversion mechanism that changes a shift state by the continuously variable transmission mechanism is disposed in the storage case, and a shaft support member that supports a shaft that is one of the components of the shift state conversion mechanism is stored in the storage case. A transmission comprising a member different from a case member constituting the case. In Claim 1, the said storage case is comprised by the case main body and the cover member attached to this case main body so that attachment or detachment is possible, and the said axial support member is attached to the said case main body so that attachment or detachment is possible. A transmission characterized by that. 3. The transmission according to claim 2, wherein the shaft support member is disposed so as to be exposed outward when the lid member is removed. An engine unit comprising the transmission according to claim 1,
The engine unit includes an engine body that generates an output, an output shaft that outputs the output, and a housing case that is integrally formed with the engine body and houses the continuously variable transmission mechanism.
The housing case includes a case main body having a through hole for the output shaft and a lid member detachably attached to the case main body, and the shaft support member is detachably attached to the case main body. An engine unit characterized by 5. The engine unit according to claim 4, wherein the shaft support member is disposed so as to be exposed outward when the lid member is removed. 5. The shaft according to claim 4, wherein one end of a shaft that is one of the constituent members of the transmission state conversion mechanism is supported by the shaft support member via a bearing, and the other end is supported by the case body via a bearing. An engine unit characterized by The engine unit according to claim 4, wherein the mounting surface of the shaft support member is deviated toward the engine main body side from the mating surface with the lid member of the case main body. 5. The engine unit according to claim 4, wherein the shaft support member includes a communication portion that communicates the lid member side and the case main body side of the housing case. The engine unit according to claim 8, wherein the communication portion is an opening. 10. The engine unit according to claim 9, wherein a rib is formed at a peripheral edge portion of the opening so as to extend in the communication direction. 9. The engine unit according to claim 8, wherein the communication portion constitutes a part of a cooling air passage through which the cooling air passes. 5. The shift state conversion mechanism according to claim 4, wherein the shift state conversion mechanism is disposed in the vicinity of a drive pulley having a blower blade, and the shaft support member has a communication portion that allows passage of wind generated by rotation of the drive pulley. And engine unit.

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