ES2448496T3 - Motor and astride type vehicle - Google Patents

Abstract

An engine (2) comprising: a transmission (60) incorporating a drive pulley (61) and a driven pulley (63); a drive shaft (62) of the pulley to drive the drive pulley (61); a crankshaft (40) provided in parallel with the drive shaft (62) of the pulley; a clutch (50) provided between the crankshaft (40) and the drive shaft (62) of the pulley and capable of connecting or disconnecting the connection of the driving force; a rotary shaft (100) of the clutch (50) arranged in parallel with the crankshaft (40); a crankcase (20) for housing the crankshaft (40) and the clutch (50); characterized by a transmission box (30) to accommodate the transmission (60), in which the transmission box is coupled to the crankcase; an oil pump (80), which is housed in the transmission case (30), to supply oil to the transmission (60); and a pump drive shaft (81, 101) for driving the oil pump in conjunction with the crankshaft.

Description

Motor and vehicle of the astride type.

Field of the Invention

The present invention relates to an engine and a vehicle of the astride type provided therewith and, specifically, it relates to an engine equipped with an oil pump for supplying oil to a transmission and a vehicle of the astride type. provided with it.

Background of the invention

Traditionally, engines have been proposed in which an oil pump for supplying oil to a transmission, which has a drive pulley and a driven pulley, is arranged upstream of a drive train clutch. An example of such an engine is described in JP-A-2006-132549.

However, because the oil pump is provided outside the transmission case to accommodate the transmission in the aforementioned conventional technique, the arrangement of the oil flow passages from the oil pump to the transmission is complicated.

The present invention has been elaborated in view of the exposed problem and, therefore, one of the objects of an embodiment of the invention consists in providing a motor in which the arrangement of the oil flow passages from a pump of oil until a transmission can be provided and a vehicle of the astride type provided with said engine.

JP10-3244287 discloses the features of the preamble of claim 1 and discloses a scooter comprising an engine that incorporates a crankcase that is integrally provided with a shaft crankcase at its rear. The scooter is equipped with a V-belt type automatic transmission that comprises a pulley driven by a belt to a drive pulley, in which the drive pulley, a mechanical feed to provide a thrust on the drive pulley and a clutch Centrifugal starters are provided on a shaft that is provided in parallel with respect to the crankshaft. The shaft is driven by the crankshaft by means of cogwheel gears and a chain.

EP 0315816 discloses a continuously variable transmission comprising a drive pulley, a driven pulley and a v-belt that interconnects those pulleys. The torque from the engine is supplied to a liquid coupling, a direct / reverse selector mechanism comprising a clutch, a drive pulley, a v-belt, a driven pulley and a differential, in that order. The CVT is contained within a shell, the shell comprising a main body having a dividing wall that separates a chamber where the continuously variable V-belt transmission is arranged from another chamber where the differential mechanism is arranged. These chambers are not completely separated from each other, but both communicate with the inside of a common oil sump unit.

Summary of the invention

An engine according to an embodiment of the invention is characterized by a transmission incorporating a drive pulley and a driven pulley; a drive shaft of the pulley to drive the drive pulley; a crankshaft aligned in parallel with the drive shaft of the pulley; a clutch provided between the crankshaft and the pulley shaft and capable of connecting or disconnecting the transmission of the drag force; and a rotating shaft of the clutch aligned in parallel with the crankshaft; a transmission case to house the transmission; a crankshaft to accommodate the crankshaft and clutch; an oil pump housed inside the transmission case to supply oil to the transmission and a pump drive shaft to drive the oil pump in combination with the crankshaft. That is, the pump shaft is coupled to the crankshaft, regardless of the connection or disconnection of the transmission of the clutch drag force. With the configuration set forth, it is possible to provide an engine in which the arrangement of the oil flow passages from the oil pump to a transmission can be facilitated.

A vehicle of the astride type, according to an embodiment of the invention, is characterized by including an engine as described above. In this way, it is possible to provide a vehicle with an engine in which the arrangement of the oil flow passages from an oil pump to a transmission can be facilitated. The astride type vehicle may be a motorcycle (including a scooter), a four-wheel buggy, or a snowmobile, for example.

Brief description of the drawings

In the following lines the description of an engine and a vehicle of the astride type will be carried out in accordance with an embodiment of the invention with reference to the drawings, in which:

FIG. 1 is a view of the left side of a motorcycle according to an embodiment of the present invention.

FIG. 2 is a view of the left loop of an engine case according to an embodiment of the present invention.

FIG. 3 is a view of the right side of the engine case according to an embodiment of the present invention.

FIG. 4 is another example of the view of the right side of the engine case according to an embodiment of the present invention.

FIG. 5 is a sectional view of the motor taken along the line V-V of FIG. 2.

FIG. 6 is a sectional view of the motor taken along line VI-VI of FIG. 2 to 4

FIG. 7 is a sectional view of the motor taken along line VII-VII of FIG. Four.

FIG. 8 is an explanatory view to show the relative positions of the axles seen from the left side of an engine.

FIG. 9 is an example of a plan view of the motorcycle according to an embodiment of the present invention.

FIG. 10 is another example of the view of the left side of the engine case according to an embodiment of the present invention.

FIG. 11 is another additional example of the view of the right side of the engine case according to an embodiment of the present invention.

FIG. 12 is a rear view of the engine case according to an embodiment of the present invention.

FIG. 13 is a bottom view of the engine case according to an embodiment of the present invention.

FIG. 14 is a sectional view along a dividing surface of the motor housing in accordance with an embodiment of the present invention.

FIG. 15 is a sectional view of the motor housing taken along line XV-XV of FIG. 14.

Detailed description of the drawings

In the present embodiment, the engine according to the invention is embodied in a three-cylinder in-line, water-cooled, three-cylinder engine, and the vehicle of the type for riding in accordance with the invention is embodied in a scooter type motorcycle. In the present embodiment, the front, rear, left, right, up and down directions are the front, rear, left, right, up and down directions seen by a driver driving the motorcycle. A right and left direction can also designate the width direction of the vehicle.

First, the motorcycle will be described. FIG. 1 is a view of the left side of a motorcycle 1. As shown in FIG. 1, the motorcycle 1 includes a front wheel 3 and a rear wheel 4 supported in rotation by its body, a seat 5 on which the driver sits, handlebars 6 to steer the front wheel 3 and a motor 2 to achieve power 4 rear wheel drive.

The seat 5 located behind the handlebars 6 extends from an intermediate portion between the front wheel 3 and the rear wheel 4 to a position above the rear wheel 4. This seat 5 is a tandem seat that has a front seat section 5a on which the driver sits in the front and a rear seat section 5b on which a passenger sits above the rear wheel. The driver sitting in the seat 5 manipulates the handlebars 6 to rotate the front wheel 3 from side to side, which is supported in rotation at the lower ends of a pair of right and left front forks 7.

The engine 2 is fixed to a body frame (not shown) that constitutes a motorcycle body frame 1. The engine 2 has a section 2b of the cylinders to accommodate the pistons (not shown). Section 2b of the cylinders extends upward while leaning forward from a position below the front section 5a of the seat 5. The engine 2 will be described in detail below.

The motorcycle 1 is also equipped with a steering line 8 driven by an axle to transmit the driving force of the engine 2 to the rear wheel 4. More specifically, the motorcycle 1 incorporates a drive shaft 9 that extends from the engine 2 to the rear wheel 4 on the left side of the body.

The drive axle 9 is supported so that it can oscillate vertically about an extended articulation axis 11 in the width direction of the vehicle. A bevel gear formed on a rear end of the drive shaft 9 engages with a bevel gear formed on a left end of a rotary axle 4a of the rear wheel, which supports the rear wheel 4 for rotation. In this way, the rear wheel 4 is supported so that it can oscillate vertically around the articulation axis 11.

The motorcycle 1 also includes a body cover 12 to cover its body. The body cover 12 includes: a front fairing 12a formed above the front wheel 3 to cover a front section of the body; leg protectors 12b shaped to cover the front part of the driver's legs sitting in the front seat section 5a of the seat 5; a central cover 12c shaped to cover an upper section of the body in a position between the handlebars 6 and the seat 5; a lateral cover 12d shaped to cover the right side and the left side of the body (that is, the sides in the width direction of the vehicle) below the central cover 12c; and a pair of right and left footrests 12e formed below the lateral cover 12d with a pair of flat right and left surfaces 12f, on which the driver seated in the front seat seat section 5a places the right and left feet.

The central cover 12c extends forward by tilting upwards from a position below a front end of the seat 5. The inclination of the central cover 12c corresponds in general terms with that of section 2b of the engine cylinders 2 arranged below the central cover 12.

The engine 4 can be started by a starter motor 12c to start driving the motorcycle 1. Air and a fuel are supplied from an intake port (not shown) to section 2b of the cylinders of the starter motor 2 by a fuel injection procedure. Engine 2 achieves power by combusting the fuel in section 2b of the cylinders. This power is transmitted to the rear wheel 4 by means of the drive shaft 9. As a result, the rear wheel 4 rotates, and the motorcycle 1 moves forward. The exhaust gases of the engine 2 discharged from an exhaust port (not shown) of the section 2b of the cylinders are released into the atmosphere after passing through a silencer 10.

Next, the engine 2 will be described in detail. FIG. 2 is a view of the left side of an engine box 2a constituting a motor frame 2. FIG. 3 and 4 are views of the right side of the engine case 2a that constitutes a motor frame 2. FIG. 2 and 3 show the engine case 2a in a state in which a cover section has been removed to partially cover one side in the vehicle width direction. FIG. 5 is a sectional view of the motor 2 taken along the line V-V of FIG. 2. FIG. 6 is a sectional view of the motor 2 taken along the line VI-VI of FIG. 2 to 4. FIG. 7 is a sectional view of the motor 2 taken along the line VII-VII of FIG. Four.

The engine case 2a incorporates a crankcase 20 to accommodate a crankshaft 40 and a transmission case 30 to accommodate a transmission 60. As shown in FIG. 5, the transmission 60 is a continuously variable wet type transmission incorporating: a drive pulley 61; a shaft 62 of the drive pulley to drive the drive pulley; a pulley 63 dragged; a shaft 64 of the driven pulley to drag the driven pulley; an endless metal belt 65 wound between the drive pulley 61 and the driven pulley 63.

As shown in FIG. 2 to 4, the crankcase 20 can be divided into upper and lower sections on the dividing surface S1 that passes through the axial center P1 of the crankshaft 40. In other words, given that two crankcase sections that are individually shaped and divisible in the upper and lower sections, the crankcase 20 has an upper section 20a of the crankcase that constitutes a section above the dividing surface S1 (that is, on the side of the section 2b of the cylinders) and a lower section 20b of the crankcase constituting a section located below the dividing surface S1. The crankcase 20 is constructed by joining a matching surface disposed in a lower part of the upper section 20a of the crankcase with a matching surface disposed over the upper part of the lower section 20b of the crankcase disposed on the dividing surface S1.

As shown in FIG. 5 to 7, the transmission case 30 is configured so that it can be divided into right and left sections on a dividing surface S2 and a dividing surface S3 which, both, are perpendicular to the axial center P1 of the crankshaft 40. In other words, the transmission box 30 has a right section 30a of the box and a left section 30b of the box, and a left terminal section 30c of the box, since three sections of the individual boxes are formed and separable from each other within the sections right and left. The right section 30a of the case constitutes a further right section of the right dividing surface S2 and covers the right side of the transmission 60 (outside the vehicle width direction). The left section 30b of the case constitutes a section between the dividing surface S2 and the left dividing surface S3, and covers the left side of the transmission 60 (within the vehicle width direction). The left terminal section 30c of the box constitutes a further left section of the dividing surface S3 and partially covers the left side of the left section 30b of the box. The transmission case 30 is constructed by joining a coincident surface disposed on a left end of the right section 30a of the case with a coincident surface disposed on a right end of the left section 30b of the case disposed on the dividing surface S2 , and by joining a coincident surface disposed on a left end of a portion of the left section 30b of the box with a coincident surface disposed on a right end of the left terminal section 30c of the box disposed on the dividing surface S3.

On the other hand, the upper section 20a of the crankcase and the lower section 20b of the crankcase 20 are respectively coupled to a portion and another portion of the transmission case 30 and, thus, the crankcase 20 and the transmission crankcase 30 they are integrated to constitute the motor box 2a.

In other words, as shown in FIG. 2, the rear portions of the upper section 20a of the crankcase and the lower section 20b of the crankcase and a front portion of the transmission case 30 are arranged in positions in which they overlap each other in the width direction of the vehicle. Likewise, the upper section 20a of the crankcase and a portion of the transmission case 30 overlaying the upper section 20a of the crankcase are fastened and fixed in the direction of the width of the vehicle while the lower section 20b of the crankcase and another portion of The transmission case 30 that overlaps with the lower section 20b of the crankcase is secured and fixed in the width direction of the vehicle.

More specifically, as shown in FIG. 2 and 5, to the right of a portion (clutch chamber 22) at the rear of a portion in which the rear crankshaft 40 is housed (crankshaft chamber 21) in the upper section 20a of the crankcase and in section 20b bottom of the crankcase, the front portions of the right section 30a of the box and the left section 30b of the box are disposed through both the crankcase sections of the upper section 20a of the crankcase and the lower section 20b of the crankcase (a across the dividing surface S1).

Likewise, as shown in FIG. 2 and 3, a plurality of retaining holes 90 are formed in corresponding positions on the rear portions of the upper section 20a of the crankcase and the lower section 20b of the crankcase, the front portion of the left section 30b of the housing and the front portion of the right section 30a of the box (see FIG. 4) which are aligned in the width direction of the vehicle. Likewise, as shown in FIG. 4 and 6, bolt members 91 that extend through the three crankcase sections in the width direction of the vehicle, are inserted into the various fastening holes 90.

More specifically, three sections of the crankcase, which are the upper section 20a of the crankcase, the left section 30b of the box, and the right section 30a of the box, are held in the vehicle width direction by the various members 91 of bolt while the other three sections of the crankcase, which are the lower section 20b of the crankcase, the left section 30b of the box and the right section 30a of the box, are also held in the direction of vehicle width by the Same bolt members.

As described above, the upper section 20a of the crankcase and the lower section 20b of the crankcase are each integrally connected with the left section 30b of the box and with the right section 30a of the box. Therefore, the rigidity of the engine case 2a is increased, especially that of the crankcase 20.

As shown in FIG. 2 to 5, the crankshaft chamber 21 extended in the width direction of the vehicle is formed in the front portion of the crankcase 20 in said engine case 2a. The crankshaft 40 is housed in the chamber 21 of the crankshaft.

The aforementioned section 2b of the cylinders extends upward while leaning forward above the crankshaft chamber 21. As shown in FIG. 5, this section 2b of the cylinders has: a block 13 of the cylinders in which three cylinders 13a are formed in line in the direction of the width of the vehicle to accommodate three pistons 13b; a cylinder head 14 of the cylinders in which three combustion chambers 14a are formed to compress and effect the combustion of the fuel in positions corresponding to the three cylinders 13a, as shown in FIG. 2; and a cover 15 to close an upper end of the cylinder head 14 of the cylinders.

As shown in FIG. 2, in correspondence with each of the three combustion chambers 14a, an intake hole 14b and an exhaust hole 14c are formed in the cylinder head 14 of the cylinders. One end of each hole is open to one side of the cylinder head 14 of the cylinders, while the other end is open to the combustion chamber 14a. The cylinder head 14 also houses an intake valve 14d that opens and closes an opening of each of the intake holes 14b to the combustion chamber 14a and an exhaust valve 14e that opens and closes an opening of each of the exhaust holes 14c to the combustion chamber 14a. A double overhead camshaft (DOHC) system is adapted for the engine 2 as a drive mechanism for the intake valves 14d and the exhaust valves 14e.

On the other hand, as shown in FIG. 5, the crankshaft 40 housed within the chamber 21 of the crankcase of the crankcase 20 has: four pins 41a to 41d, each of which adopts a cylindrical configuration and extends in the direction of the width of the vehicle, so that its center axial corresponds to the axial center P1 of the crankshaft 40; three pairs of crankshaft arms 42 each adopting the form of a plate extending in a direction perpendicular to the axial central P1; and three crankshafts 43 of the crankshaft each of which extends in the direction of the width of the vehicle to connect with a pair of crankshaft arms 42 in a position separated from the axial center P1. The plugs 41a to 41d, the crankshaft arms 42, and the crankshaft dies 43 are integrally formed.

The three pairs of crankshaft arms 42 are formed in positions corresponding to the three cylinders 13a formed within the block 13 of the cylinders. Next, the three crankshafts 43 of the crankshaft are each coupled to the lower end of a strut-shaped connecting rod 13c that supports the piston 13b from below.

The crankshaft 40 is supported within the crankcase 20 to rotate around the axial center P1 in accordance with the reciprocating movement of the three pistons 13b disposed within the cylinders 13a that are coupled to the crankshaft 40 by means of the connecting rods 13c.

More specifically, as shown in FIG. 5, a plain bearing 21a for supporting the journal 41a which constitutes a left end portion of the crankshaft 40 is formed on the left wall to close the left side of the crankcase chamber 21. A plain bearing 21d for supporting the journal 41d constituting a right end portion of the crankshaft 40 is formed on a left wall to close the left side of the chamber 21 of the crankshaft. A plain bearing 21d for supporting the journal 41d constituting a right end portion of the crankshaft 40 is formed on a right wall to close the right side of the chamber 21 of the crankshaft. Likewise, within the crankshaft chamber 21 a plain bearing 21b is shaped to support the journal 41b which extends between a left terminal pair of the crankshaft arms 42. A plain bearing 21d is also formed to support the journal 21c that extends between the intermediate pair of the crankshaft arms 42 and a right terminal pair of the crankshaft arms 42. The bearings 41a to 41d of the crankshaft 40 are supported respectively by plain bearings 21a to 21d with flat bearings (not shown) that adopt a cylindrical configuration with a thin wall and arranged to cover the peripheries of the bearings 41a to 41d.

A left terminal portion of the crankshaft 40 projects to the left of the crankshaft chamber 21, and a generator 44 is mounted on the left end of the crankshaft 40 to produce electrical energy in accordance with the rotation of the crankshaft 40. The generator 44 incorporates a rotor that has a magnet and rotates in solidarity with the crankshaft 40, and a stator coil arranged in front of the magnet. Likewise, the generator 44 is capable of producing electric power with the rotor rotating in combination with the crankshaft 40. The electric power produced by the generator 44 is supplied to, for example, a battery (not shown) provided inside the motorcycle 1 (see FIG. 1). A cover member 20c for covering the exterior generator 44, in the direction of the width of the vehicle is removably fixed to the left side of the crankshaft chamber 21.

As shown in FIG. 2 to 4, a gear 45a that meshes with a gear (not shown) on the periphery of a compensator 47 (see FIGS. 2 to 4) disposed below the crankshaft 40, is formed between the right terminal arm 42 of the crankshaft 40 and the plain bearing 21d to support the right terminal groove 41d. The compensator 47 is supported in rotation inside the crankcase 20 with an axle (not shown) extending in the direction of the width of the vehicle. That is, a bearing 47a that supports the shaft for dragging the compensator 47 is formed inside the crankcase 20. This compensator 47 is arranged in front and slightly below the crankshaft 40 so that an axial center of the compensator 47 is located on the surface S1 crankcase partition 20.

Likewise, as shown in FIG. 5, a right end portion of the crankshaft 40 projects to the chamber 21 of the crankshaft and a gear 45b is formed on the right end portion of the crankshaft 40. A chain 46 for opening and closing the intake valves 14d and the exhaust valves 14e (see FIG. 2) of the cylinder head 14 of the cylinders shown in FIG. 2 in the DOHC system is wrapped around gear 45b. A cover member 20d for covering the side of the right end of the crankshaft 40 in the width direction of the vehicle is removably attached to the right side of the crankcase chamber 21.

As shown in FIG. 5, the engine 2 is also equipped with a clutch 50 which can connect or disconnect the drive of the drag force from the crankshaft 40 to the axis 62 of the drive pulley 60. This clutch 50 is housed inside the crankcase. twenty.

More specifically, the clutch chamber 22 to accommodate the clutch 50 is arranged in parallel with the clutch chamber 21 inside the crankcase 20. A left portion of the crankshaft chamber 21 projects backward to form this clutch chamber 22. A left wall to close a left side of the clutch chamber 22 is formed as a detachable cover member 20e.

In this embodiment, the clutch 50 is a multi-plate clutch. This clutch 50 has: a section 51 upstream of the clutch that constantly rotates in combination with the crankshaft 40; a section 52 downstream of the clutch that may be engaged with section 51 upstream of the clutch; and a shaft 53 of the clutch that rotates in solidarity with section 52 downstream of the clutch; and a pressure plate 54 for controlling the engagement and disengagement of section 51 upstream of the clutch with section 52 downstream of the clutch.

A gear 51b is formed on a periphery of section 51 upstream of the clutch. This gear 51 gears with a gear 42g formed on a periphery of the right arm 42 of the crankshaft disposed in the left terminal pair of the arms 42 of the crankshaft arranged in the crankshaft 40. Therefore, while the crankshaft 40 rotates, section 51 upstream of the clutch is kept rotating in combination with the crankshaft 40.

The section 51 upstream of the clutch has: a plurality of upstream discs 51a arranged by a separation determined by a disc 51a upstream and another in the direction of the width of the vehicle; and the gear 51b arranged to the right of the various discs 51a upstream. On the other hand, the section 52 downstream of the clutch has a plurality 52a downstream arranged with a predetermined separation between a disc 52a downstream and another in the vehicle width direction. The disks 51a upstream and the disks 52a downstream are alternately arranged to overlap each other in the width direction of the vehicle. The pressure plate 54 arranged to the left of the disks 51a upstream and the disks 52a downstream is forced to the right by a spring, which is not shown, and presses the disks 51a upstream against the disks 52a downstream. Accordingly, section 51 upstream of the clutch and section 52 downstream of the clutch are connected. In a state in which section 51 upstream of the clutch and section 52 downstream of the clutch are connected (hereinafter referred to as "connected state"), section 51 upstream of the clutch, section 52 downstream of the clutch and the shaft 53 of the clutch rotates in a integral manner, and the rotational drag force of the crankshaft 40 is transmitted to the shaft 53 of the clutch.

On the other hand, the engagement of the disks 51a upstream and with the disks 52a downstream can be suppressed by moving the pressure plate 54 to the left by actuating a rod (not shown) connected to the plate 54 Pressure. In said state in which the fitting of section 51 upstream of the clutch with section 52 downstream of the clutch is suppressed (hereinafter referred to as "disconnected state"), only section 51 upstream of the broken clutch and, by therefore, the rotational drag force of the crankshaft 40 is not transmitted to the axis 53 of the clutch. The aforementioned rod for switching the connected state and the disconnected state of the clutch 50 can be operated, for example, by the driver of the motorcycle 1 with a clutch lever (not shown) provided in the handlebars 6 (see FIG. 1) or by an actuator, which is not shown, provided on the motorcycle 1. This actuator can be operated by hydraulic pressure or by a motor, for example, on the basis of an input of electrical instructions by the driver through an instruction input means (a button, etc.), which is not shown but is disposed on the motorcycle 1 or based on an output of electrical instructions from a Motor Control Unit (ECU), which is not It is shown but is provided on the motorcycle 1 according to the speed of the engine 2 and the like. The clutch 50 may also be a centrifugal clutch that switches the connected state and the disconnected state in accordance with the centrifugal force associated with the rotation of section 51 upstream of the clutch.

As shown in FIG. 2 and 5, the clutch shaft 53 is formed separately from the crankshaft 40 and is arranged in parallel with the crankshaft 40 in a position adjacent to the crankshaft 40. Also, the clutch shaft 53 is disposed behind the crankshaft 40 and above the dividing surface S1 of the crankshaft 40 and the crankcase 20.

This axis 53 of the clutch is supported in rotation inside the crankcase 20. More specifically, as shown in FIG. 5, a left clutch shaft bearing 22a for supporting a left end of the clutch shaft 53 is formed on the left wall of the clutch chamber 22. An intermediate bearing 22b of the clutch shaft for supporting an intermediate portion of the clutch shaft 53 is formed on a right wall of the clutch chamber 22. Also, to the right of the clutch chamber 22, a right bearing 22c of the clutch shaft to support a right terminal portion of the clutch shaft 53 is formed on a portion of the rear wall of the projected crankshaft chamber 21 more distance to the rear. The left bearing 22a of the clutch shaft, the intermediate bearing 22b of the clutch shaft, and the right bearing 22c of the clutch shaft are all formed within the upper section 20a of the crankcase (see FIG. 2). The shaft 53 of the clutch is supported by each of the bearings 22a to 22c with a ball bearing.

As shown in FIG. 2, an oil sump unit 23 on the side of the crankcase for storing the lubricating oil is formed in a portion of a lower section of the crankcase 20 below the crankshaft chamber 21. The lubricating oil flows down by the force of gravity from the crankshaft chamber 21 and from the clutch chamber 22 disposed within the crankcase 20 to the crankcase unit 23 of the crankcase side oil. An oil reservoir 24 for storing the lubricating oil transferred from the crankcase unit 23 of the crankcase side oil is formed in another portion of the lower section of the crankcase 20, adjacent to the crankcase unit 23 of the crankcase side oil, below the crankshaft chamber 22.

As shown in FIG. 2 and 6, the engine 2 includes a crankcase oil pump 82 for supplying lubricating oil to a section of the engine that includes elements such as the crankshaft 40, the section 2b of the cylinders, the clutch 50 (see FIG. 5) and upstream of the clutch 50 in a transmission step of the driving force of the engine 2. The oil pump 82 on the crankcase side is housed inside the crankcase 20, is located between the clutch 50 and the driving pulley 61 in the direction of the width of the vehicle (see FIG. 6), and is arranged below the clutch 50 and the drive pulley 61 in a side view (see FIG. 2).

The oil pump 82 on the crankcase side has: a sweeping pump 83 for transferring the lubricating oil disposed in the crankcase unit 23 of the crankcase oil to the oil reservoir 24; and a feed pump 84 for sending the lubricating oil into the oil reservoir 24 to each of the components of the engine 2 under pressure. The sweeping pump 83 and the feeding pump 84 are integrally configured and are integrated between a right pump support section 29a and a left pump support section 29b as crankcase portions 20. In this embodiment , the sweeping pump 83 and the feed pump 84 are both trocoidal pumps and have, respectively, a pair of internal rotors 83a, 84a and external rotors 83b, 84b.

As shown in FIG. 2, an upper end of a filter 25 for aspirating the lubricating oil from the crankcase unit 23 of the oil on the crankcase side into the sweeping pump 83 is connected to the sweeping pump 83. An intake section 25a for sucking the lubricating oil into the crankcase unit 23 of the oil on the crankcase side is formed at a lower end of the filter 25. Also, an oil flow passage (not shown) to guide the lubricating oil Discharged from the sweeping pump 83 to the oil reservoir 24 is formed between the sweeping pump 83 and an upper end of the oil reservoir 24.

As shown in FIG. 2, an upper end of a filter 26 to aspirate the lubricating oil from the oil reservoir 24 into the feed pump 84 is connected to the feed pump 84. An intake section 26a for sucking the lubricating oil from the oil reservoir 24 is formed at a lower end of this filter 26. Also, an oil flow passage 28a to guide the lubricating oil discharged from the feed pump 84 to the Oil filter 27 is formed between the feed pump 84 and the oil filter 27 formed in the front portion of the crankcase 20.

Likewise, as shown in FIG. 2, a main oil flow passage (main gallery) 28c extending in the width direction of the vehicle is formed below the crankcase chamber 21 of the crankcase 20, and an oil flow passage 28b is also formed between the oil flow passage 28c and the oil filter 27. The lubricating oil pumped from the oil reservoir 24 to the oil filter 27 by the feed pump 84 is filtered by an element (not shown) included in the oil filter 27 and then flows into the interior of step 28c of main oil flow through the oil flow passage 28b extending backward from the oil filter 27. After this, as shown in FIG. 5, the lubrication of the oil pumped through the main oil flow passage 28c is supplied to the crankshaft chamber 21 and to the section 2b of the cylinders through an oil injection passage 28d formed in each of the plain bearings 21a to 21d to support the stumps 41a to 41d of the crankshaft 40 and through an oil flow passage 28e formed within each of the stumps 41a to 41d.

As shown in FIG. 6, the crankcase, the engine 2 is also equipped with an axis 85a of the oil pump on the crankcase side that draws the oil pump 82 from the crankcase side and an axis 85b of the cooling water pump that drags a pump 87 of the cooling water to circulate the cooling water inside the engine 2. The respective rotors 83a, 84a internal to the sweeping pump 83 and the feed pump 84 are connected to a periphery of the axis 85a of the oil pump on the crankcase side and rotate jointly with the shaft 85a of the crankcase oil pump. The cooling water pump 87 is fixed to a left end of the axis 85b of the cooling water pump. The shaft 85a of the oil pump on the crankcase side and the shaft 85b of the axis of the cooling water pump are formed separately from each other and are coaxially coupled. More specifically, a left end of the shaft 85a of the oil pump on the crankcase side and a right end of the shaft 85b of the cooling water pump are respectively formed with a projection and a recess whose configurations correspond to each other. The left end of the shaft 85a of the crankcase side shaft pump is coupled to the right end of the shaft 85b of the cooling water pump by coupling the projection with the recess. As a result, an axial center of the shaft 85a of the oil pump on the crankcase side is oriented with the shaft 85b of the cooling water pump to constitute a single shaft 85 of the pump on the crankcase side. Therefore, the shaft 85a of the oil pump on the crankcase side and the shaft 85b of the water cooling pump rotate jointly.

This shaft 85 of the crankcase side pump is constituted separately from the crankshaft 40 (see FIG. 5) and the clutch shaft 53 and is arranged in parallel with the clutch shaft 53 in a position adjacent to the clutch shaft 53 . The shaft 85 of the pump shaft on the crankcase side is also arranged behind the crankshaft 40 and below the shaft 62 of the drive pulley and the shaft 64 of the driven pulley.

The shaft 85 of the crankcase side pump is supported in rotation by the crankcase 20. More specifically, as shown in FIG. 6, a left crankcase bearing 59c of the crankcase side pump to support a left terminal portion of the crankcase side pump 85 is formed on the left crankcase wall 20 to close the left side of the pump 82 of crankcase oil. An intermediate portion of the shaft 85 of the crankcase side pump is supported by the right pump support section 29a and by the left pump support section 29b by means of the crankcase oil pump 82. Also, a right section 29d of insertion of the pump on the crankcase side through which a right terminal portion of the shaft 85 of the crankcase pump is inserted is formed on the right wall of the crankcase 20 to close the side right of the oil pump 82 on the crankcase side.

An intermediate gear 86 supported in rotation by the crankcase 20 is disposed between the shaft 85 of the crankcase side pump and the shaft 53 of the clutch. A gear 51c that meshes with the intermediate gear 86 is formed on the periphery of the section 51 upstream of the clutch clutch 50 and a gear 85c that also meshes with the intermediate gear 86 that is fixed to a periphery of the pump shaft 85 from the crankcase side. That is, the section 51 upstream of the clutch and the shaft 85 of the crankcase side pump are coupled to each other through the intermediate gear 86.

This makes it possible for the shaft 85 of the crankcase-side pump to rotate in combination with the crankshaft 40 irrespective of the connection or disconnection of the transmission of the drag force by the clutch 50. Consequently, the oil pump 82 from the crankcase side fixed to the axis 85 of the crankcase pump can be continuously pulled in the disconnected state of the clutch 50 as well as in the connected state of the clutch 50. Therefore, the oil pump 82 on the crankcase side is capable of supplying lubricating oil to the crankshaft chamber 21 and the section 2b of the cylinders through said oil flow steps 28a to 28e while the crankshaft 40 is rotating.

Likewise, the cooling water pump 87 driven by rotation of the shaft 85 of the crankcase side pump can also be continuously driven to circulate the cooling water to each engine component 2 even in the disconnected state of the clutch 50.

On the other hand, as shown in FIG. 5, the transmission 60 is housed within the transmission case 30. More specifically, an extended transmission chamber 31 is arranged in a longitudinal direction between the right section 30a of the case and the left section 30b of the case within the transmission case 30, and the transmission 60 is housed within the chamber 31 of transmission. A front side portion of this transmission chamber 31 is disposed to the right of the chamber 22 of the crankcase clutch 20, and its rear side portion extends further back than the crankcase 20.

The drive pulley 61 and the shaft 62 of the drive pulley are housed in the front side portion of the transmission chamber 31. The shaft 62 of the drive pulley is disposed separately from the crankshaft 40 and the shaft 53 of the clutch and is arranged in parallel with the crankshaft 40 adjacent to the crankshaft 40.

This shaft 62 of the drive pulley is supported in rotation by the transmission case 30. More specifically, a right bearing 33a of the drive pulley shaft to support a right end of the drive pulley shaft 62 is formed in the right section 30a of the case to close the right side of the transmission chamber 31, and a left bearing 33b of the drive pulley to support a left terminal portion of the shaft 62 of the drive pulley is formed in the left section 30b of the housing to close the left side of the transmission chamber 31. Likewise, as shown in FIG. 3 and 4, the right bearing 33 of the drive pulley shaft and the left bearing 33b of the drive pulley shaft 30 are both formed above the surface S1 of the crankcase 20.

This shaft 62 of the drive pulley is coaxially coupled with the shaft 53 of the clutch. More specifically, as shown in FIG. 5 and 6, the right end of the clutch shaft 53 is coupled to the left end of the drive pulley 62 by means of a grooved connection. Consequently, the axial center of the axis 53 of the clutch is oriented to that of the axis 62 of the drive pulley to constitute a single axis (hereinafter referred to as "complex main axis 100") extended in the direction of the vehicle width from the crankcase 20 to the transmission case 30. In this way, the shaft 53 of the clutch and the shaft 62 of the drive pulley rotate jointly.

As shown in FIG. 5 and 6, the complex main shaft 100 is constituted separately from the crankshaft 40 and is arranged in parallel with the crankshaft 40 adjacent to the crankshaft 40. A left end of the complex main shaft 100 is supported by the left bearing 22a of the Clutch shaft on the crankcase 20. Also, a right end of the complex main shaft 100 is supported by the right bearing 33a of the drive pulley shaft within the transmission case. Likewise, an intermediate portion of the complex main shaft 100 is supported by the right bearing 22c of the clutch shaft inside the crankcase 20 and by the bearing 33b of the drive pulley shaft inside the transmission case 30. Likewise, as shown in FIG. 2 to 4, the complex main shaft 100 is disposed behind the crankshaft 40 and above the crankshaft 40 and the dividing surface S1 of the crankcase 20.

As shown in FIG. 5 and 6, the right bearing 22 of the clutch shaft to support the right end of the clutch shaft 53 and the left bearing 33b of the drive pulley shaft to support the left end of the drive shaft 62 of the drive pulley are formed by adopting configurations that correspond to each other and are coupled to each other. More specifically, a cylindrical projection projecting to the right from the crankcase 20 is formed in the right bearing 22c of the clutch shaft around the right terminal portion of the clutch shaft 53. On the other hand, a cylindrical projection projecting to the left from the left section 30b of the case is formed in the left bearing 33b of the drive pulley shaft around the left end portion of the shaft 62 of the drive pulley. Here, an inner diameter of the outer bearing cylinder 22c of the clutch shaft is generically equal to an outer diameter of the left bearing 33b of the drive pulley shaft, and the left bearing cylinder 33b of the drive pulley shaft is adjusted inside the right bearing 22c of the clutch shaft. An O-ring 30j for sealing is secured between the inner periphery of the right bearing cylinder 22c of the clutch shaft and an outer periphery of the left bearing cylinder 33b of the drive pulley shaft.

Next, the shaft 62b of the drive pulley and the shaft 53 of the clutch are coupled to each other in a portion where the right bearing 22c of the clutch shaft engages with the left bearing 33b of the drive pulley shaft. That is, a coupling portion between the shaft 62 of the drive pulley and the shaft 53 of the clutch in the complex main shaft 100 is inserted into a coupling portion between the right bearing 22c of the clutch and the bearing 33b of the drive shaft. the drive pulley.

The transmission case 30 is coupled to both the upper section 20a of the crankcase and the lower section 20b of the crankcase which have been described above, mainly around the complex main axis 100 through both upper and lower sides of section S1 crankcase partition 20. More specifically, as shown in FIGs. 2 and 3, the various fastening holes 90 mentioned above are formed in a surrounding portion of the clutch shaft 53 of the upper section 20a of the crankcase, in a surrounding portion of the clutch shaft 53 of the lower section of the crankcase, and in the surrounding portions of the shaft 62 of the drive pulley both in the right section 30a of the box and in the left section 30b of the box. Next, as shown in FIG. 4 and 6, a combination of three crankcase sections, which are the upper section 20a of the crankcase, the left section 30b of the box, and the right section 30a of the box, and another combination of three crankcase members, which they are the lower section 20b of the crankcase, the left section 30b of the box and the right section 30a of the box, by means of the various bolt members 91 around the complex main axis 100 in the vehicle width direction.

As shown in FIG. 5 and 6, the drive pulley 61 is formed on a periphery of the shaft 62 of the drive pulley. The drive pulley 61 incorporates a sheave on the drive side disposed on the inner part of the vehicle width direction and a removable sheave 61b on the drive side formed on the outer side in the direction of the vehicle width. The sheave 61a fixed on the drive side is formed integrally with the shaft 62 of the drive pulley. The removable sheave 61b on the drive side is formed separately from the axis 62 of the drive pulley, and the axis 62 of the drive pulley is inserted through its central portion. The removable sheave 61b on the drive side is adapted to be able to slide on the periphery of the shaft 62 of the drive pulley in one direction along an axial center P2 of the shaft 62 of the drive pulley. A distance between the removable sheave 61b from the drive side and the fixed sheave 61a from the drive side changes according to the axial displacement of the removable sheave 61b from the drive side, and consequently, changes a diameter of a portion of the pulley 61 drag where a metal belt is wrapped around (in the

successively designated as "effective diameter").

The sliding of this removable sheave 61b from the drive side is hydraulically controlled. More specifically, a cover 61d of the drag side is fixed to the right side of the removable sheave 61b of the drag side to form between them a closed space to accommodate the hydraulic control oil (hereinafter referred to as

"Section 61c of oil housing of the drag side"). When the amount of oil stored in this

section 61c of oil housing of the drag side increases, the removable sheave 61b of the drag side moves to the left. Then, the distance between the fixed sheave 61a of the drive side and the removable sheave 61b of the drive side decreases and the effective diameter of the drive pulley 61 increases. On the other hand, when the amount of oil stored in the drag housing oil section 61c decreases, the removable sheave 61b of the drag side shifts to the right. Then, the distance between the fixed sheave 61a on the drive side and the removable sheave 61b on the drive side increases and the effective diameter of the drive pulley 61 decreases.

As shown in FIG. 5, the driven pulley 63 and the shaft 64 of the driven pulley are housed behind the drive pulley 61 and the axis 62 of the drive pulley within the transmission chamber 31. The shaft 64 of the driven pulley is formed separately from the crankshaft 40 and the shaft 53 of the clutch and is arranged in parallel with the shaft 62 of the drive pulley in a position adjacent to the shaft 62 of the drive pulley.

This shaft 64 of the driven pulley is supported in rotation by the transmission case 30. More specifically, a right bearing 34a of the driven pulley shaft to support a right end of the shaft 64 of the driven pulley is formed within the right section 30a of the case, and a bearing 34b of the shaft of the driven pulley to support a left terminal portion of the shaft 64 of the driven pulley is formed within the left section 30b of the box.

As described above, a right section 30a of the case includes, and is integrally formed with, the right bearing 33a of the drive pulley shaft to support the right end of the shaft 62 of the drive pulley and bearing. 34a right of the shaft of the driven pulley to support the right end of the shaft 64 of the driven pulley. (See FIG. 4 and 5). Likewise, the left section 30b of the case includes, and is integrally formed with, the left bearing 33b of the drive pulley shaft to support the left end of the shaft 62 of the drive pulley and the left bearing 34b of the shaft of the driven pulley to support the left end of the shaft 64 of the driven pulley (see FIGS. 6 and 5). That is, the right bearing 33a of the drive pulley shaft and the right bearing 34a of the driven pulley shaft are integrally formed with the right section 30a of the case, and the left bearing 33b of the drive pulley shaft. drag, and the left bearing 34b of the driven pulley shaft are integrally formed with the left section 30b of the case.

As shown in FIG. 5, the driven pulley 63 is formed on the periphery of the axis 64 of the driven pulley. The dragged pulley 63 has a fixed sheave 63a of the dragged side arranged on the outer part in the direction of the width of the vehicle and a removable sheave 63b of the dragged side formed on the inner side in the direction of the width of the vehicle. The fixed sheave 63a on the driven side is integrally formed with the axis 64 of the driven pulley. On the other hand, the removable sheave 63b of the driven side is formed separately from the axis 64 of the driven pulley, and the axis 64 of the driven pulley is inserted through its central portion. Likewise, the removable sheave 63b of the dragged side is adapted to be able to slide on the periphery of the shaft 64 of the driven pulley in one direction along an axial center P3 of the axis 64 of the driven pulley. A distance between the removable sheave 63b of the dragged side and the fixed sheave 63a of the dragged side changes according to the axial displacement of the removable sheave 63b of the dragged side. Consequently, an effective diameter of the driven pulley 63 changes.

A cover 63d of the dragged side is fixed on the left side of the removable sheave 63b of the dragged side is formed between them to accommodate the oil for hydraulic control (hereinafter referred to as "section 63c of housing of the oil of the dragged side"). A helical spring for pressing the removable sheave 63b from the dragged side to the side of the fixed sheave 63a of the dragged side is housed in the oil housing section 63c of the dragged side. The length of the metal belt 65 wound between the drive pulley 61 and the driven pulley 63 is constant. Therefore, when the effective diameter of the drive pulley 61 increases, the removable pulley 63b of the dragged side slides towards the side of the fixed sheave 63a of the dragged side against the pressing force of the helical spring to reduce the effective diameter of the pulley 63 dragged. On the contrary, when the effective diameter of the drive pulley 61 decreases, the effective diameter of the driven pulley 63 increases.

Likewise, as shown in FIG. 5, the motor 2 includes an output shaft 70 to generate the drag force to the other side downstream transmitted from the crankshaft 40 to the shaft 64 of the driven pulley. The output shaft 70 is constituted separately from the axis 64 of the driven pulley and is arranged in parallel with the axis 64 of the driven pulley in a position adjacent to the axis 64 of the driven pulley.

As shown in FIGs. 2 to 5, the entire output shaft 70 is disposed outside the crankcase 20. In other words, the output shaft 70 is entirely housed within the transmission case 30 behind the crankcase 20. More specifically, a chamber 32 The output is formed between the left section 30b of the box and the left terminal section 30c of the transmission box 30. A left side portion of the output shaft 70 is housed within the output chamber 32, and a right side portion of the output shaft 70 is housed within the transmission chamber 31.

The output shaft 70 is constituted by coaxially coupling a right section 70a of the output shaft as a right side portion housed within the transmission chamber 31 to a left section 70b of the output shaft as a left side portion housed inside the chamber 32 output More specifically, as shown in FIG. 5, a left end of the section 70a of the output shaft and a right end of the left section 70b of the output shaft are shaped by adopting cylindrical configurations that correspond to each other and also mate with each other.

Likewise, the right section 70a of the output shaft and the left section 70b of the output shaft are coupled together so that they can be divided into right and left sections. More specifically, a fitting groove of a predetermined length that extends above the right section 70a of the output shaft and the left section 70b of the output shaft in the direction of the width of the vehicle is formed within a portion coupling located between the right section 70a of the output shaft and the left section 70b of the output shaft. On the other hand, a cylindrically shaped exit member 70c extending over the right section 70a of the output shaft and the left section 70b of the output shaft in the direction of the width of the vehicle and that fits the groove of lace, is fixed to a periphery of the coupling portion. A rod, which is not shown, is fixed to the projections formed on a periphery of this fitting member 70c. The fitting member 70c can slide on the periphery of the output shaft 70 along its axial center P4 with the activation of this rod. The fitting member 70c is disposed through both the right section 70a of the output shaft and the left section 70b of the output shaft in a coupling state shown in FIG.

5. However, the fitting member 70c may also be disposed only on the periphery of the left section 70b of the output shaft by sliding the leftmost fitting member 70c from the left end of the right section of the shaft 70a. output, for example with the activation of the rod by the driver of the motorcycle 1. As a result, the right section 70a of the output shaft and the left section 70b of the output shaft can be separated from each other releasing the coupling between them. In this separate state, the left section 70b of the output shaft can rotate independently of the right section 70a of the output shaft.

The output shaft 70 is supported in rotation by the transmission case 30. More specifically, a right bearing 35a of the output shaft to support a right end of the output shaft 70 (that is, a right end of the right section 70a of the output shaft) is formed in the right section 30a of the housing, and a left bearing 35c of the output shaft to support a left end of the output shaft 70 (that is, a left terminal portion of the left section 70b of the output shaft) is formed within the output chamber 32 of section 30c left terminal of the box. Also, an intermediate bearing 35b of the output shaft for supporting an intermediate portion of the output shaft 70 (that is, the coupling portion disposed between the right section 70a of the output shaft and the left section 70b of the output shaft) is formed within the left section 30b of the box. That is, the right section 70a of the output shaft and the left section 70b of the output shaft are interconnected within a through hole formed in the intermediate bearing 35b of the output shaft as a boundary between the transmission chamber 31 and the chamber 32 output.

A gear 70d is fixedly attached to the right terminal portion of the output shaft 70. This gear 70d meshes with a gear 64a fixed to the right terminal portion of the shaft 64 of the driven pulley. Therefore, the output shaft 70 rotates in conjunction with the shaft 64 of the driven pulley.

Likewise, as shown in FIG. 5, a coupling shaft 71 that couples the output shaft 70 to the drive shaft 9 (see FIG. 1) is housed within the output chamber 32. This coupling shaft 71 is formed to extend backward from the left side of the output shaft 70.

A bevel gear 71a that meshes with a bevel gear 70e on the left end of the output shaft 70 is fixed to a leading end of the coupling shaft 71. Therefore, the coupling shaft 71 rotates in conjunction with the output shaft 70. A universal joint 71b for coupling a front end of the drive shaft 9 for rotation is fixed to a rear end of the coupling shaft 71.

The coupling shaft 71 is supported in rotation by the transmission case 30. More specifically, a front bearing 36a of the coupling shaft for supporting the front terminal portion of the coupling shaft 71 is formed in the front portion of the outlet chamber 32 in the left terminal section 30c of the housing, and a rear bearing 36b of the coupling shaft to support the rear terminal portion of the coupling shaft 71 is formed in the rear portion of the output chamber 32.

As shown in FIG. 6, the engine 2 includes an oil pump 80 on the transmission side to supply oil to the transmission 60. This oil pump 80 on the transmission side is housed within the transmission chamber 31 of the transmission case 30. More specifically, as shown in FIG. 3 and 4, the oil pump 80 on the transmission side is located adjacent to the drive pulley 61 and the driven pulley 63 and is disposed below the drag pulley 61 and the pulley 63 pulled into the transmission chamber 31.

As shown in FIG. 6, in this embodiment, the oil pump 80 on the transmission side is a trocoidal pump and has a pair of internal rotors 80a and external rotors 80d. This transmission side 80 oil pump is supported by a support section 37 of the transmission side pump, which is a part of the left section 30b of the transmission case box 30.

Likewise, the engine 2 includes a shaft 81 of the transmission side pump to drive the oil pump 80 from the transmission side. The internal rotor 80a of the transmission side oil pump 80 is connected to a periphery at the right end of the shaft 81 of the transmission side pump to rotate in solidarity with the axis 81 of the side pump the broadcast.

The shaft 81 of the transmission side pump is formed separately from the crankshaft 40, the shaft 53 of the clutch, the shaft 62 of the drive pulley and the shaft 64 of the driven pulley, and is arranged in parallel with the shaft 62 of the drive pulley and of the shaft 64 of the driven pulley in a position adjacent to the axis 62 of the drive pulley and of the shaft 64 of the driven pulley. Likewise, as shown in FIG. 3 and 4, this shaft 81 of the transmission side pump is disposed behind the crankshaft 40, in front of the output shaft 70, and below the shaft 62 of the drive pulley and the shaft 64 of the driven pulley . That is, the shaft 81 of the transmission side pump is disposed in a position surrounded by the crankshaft 40, the shaft 62 of the drive pulley, the shaft 63 of the driven pulley and the output shaft 70, and in a position below the dividing surface S1 of the crankcase 20 of the crankshaft.

The shaft 81 of the transmission side pump is supported in rotation within the transmission case 30. More specifically, as shown in FIG. 6, the shaft 81 of the transmission side pump is supported by the pump support section 37 of the transmission side in the left section 30b of the housing by means of the transmission side oil pump 80 . Likewise, a transmission 37c for insertion of the transmission side pump into which a left end of the shaft 81 of the transmission side pump is inserted is formed within a portion that closes the left side of the pump 80 of the transmission side oil in the left section 30b of the box.

Also, the shaft 81 of the transmission side pump is coaxially coupled to the shaft 85 of the crankcase side pump. This is, as shown in FIG. 6, the left end of the shaft 81 of the transmission side pump is coupled to the right end of the shaft 85 of the pump on the crankcase side. More specifically, a groove of engagement with a predetermined length extending over the axis 81 of the pump on the transmission side and axis 85 of the pump on the crankcase side in the direction of the width of the vehicle is formed in a coupling portion disposed between shaft 81 of the transmission side pump and shaft 85 of the crankcase side pump. Likewise, a fitting member 88 with a cylindrical configuration that extends above the axis 81 of the pump on the transmission side and the axis 85 of the pump on the crankcase side in the direction of the width of the vehicle and which fits with The lace groove is fixed to a periphery of this coupling portion. Accordingly, the axial center of the axis 85 of the pump on the crankcase side is oriented with that of the axis 81 of the pump on the transmission side to constitute a single axis (hereinafter referred to as "complex axis 101 of the pump ”) extending in the direction of the width of the vehicle from the crankcase 20 to the transmission case 30. Thus, the pump 85 of the shaft on the crankcase side and the shaft 81 of the pump on the transmission side rotate jointly.

This complex shaft 101 of the pump is formed separately from the crankshaft 40 and the complex main shaft 100 and is arranged in parallel with the complex main axis 100 in a position adjacent to the complex main axis 100. A left end of the complex pump shaft 101 is supported by the left bearing 29c of the crankcase side pump shaft inside the crankcase 20. An intermediate portion of the pump complex shaft 101 is supported by the right support section 29a of the pump and by the left section 29b of the pump support by means of the oil pump 82 on the crankcase side. Likewise, a right end of the complex shaft 101 of the pump is supported by the section 37 of the transmission side pump inside the transmission case 30 by means of the oil pump 80 on the transmission side.

The complex shaft 101 of the pump rotates in conjunction with the crankshaft 40 regardless of the connection or disconnection of the transmission of the drag force by the clutch 50. Accordingly, the axis 81 of the pump on the fixed transmission side to the right end of the complex shaft 101 the pump can be continuously pulled in the disconnected state of the clutch 50 as well as in the embedded state of the clutch 50. Thus, the oil pump 80 on the transmission side can supply both an oil for the hydraulic control as a lubricating oil to the transmission 60 while the crankshaft 40 is rotating.

The insertion section 29d of the crankcase-side pump through which the right end of the shaft 85 of the crankcase-side pump is inserted, and the insertion section 37c of the transmission-side pump through which the left end of the shaft 81 of the pump on the transmission side is inserted, each is shaped so that they correspond to each other and are coupled to each other. More specifically, in the right insertion section 29d of the pump on the crankcase side, a cylindrical portion is projected to the right from the crankcase 20 of the crankshaft, about the axis 85 of the crankcase side pump. On the other hand, in the insertion section 37c of the transmission side pump, a cylindrical projection is formed which projects to the left from the left section 30b of the housing, around the axis 81 of the pump on the side of the broadcast. Here, an outer diameter of the cylinder of the right insertion section 29d of the crankcase side pump is generically equal to an inner diameter of the cylinder of the insertion section 37c of the transmission side pump. Thus, the right insertion section 29d of the pump on the crankcase side is coupled within that of the insertion section 37c of the transmission side pump.

Also, the shaft 85 of the crankcase-side pump and the shaft 81 of the transmission-side pump are coupled to each other in a portion where the right insertion portion 29d of the crankcase-side pump is coupled within the insertion section 37c of the transmission side pump. That is, the coupling portion between the shaft 85 of the pump on the crankcase side and the shaft 81 of the pump on the transmission side within the complex shaft 101 of the pump is inserted into the coupling portion disposed between section 29d crankcase pump insertion right and drive insertion section 37c of the transmission side.

The aforementioned coupling between the lower section 20b of the crankcase and the transmission case 30 is also directed around the complex shaft 101 of the pump. More specifically, as shown in FIG. 2 and 3, the various fastening holes 90 mentioned above are formed in a surrounding area around the axis 85 of the crankcase side pump disposed in the lower section 20b of the crankcase and in a surrounding area around the axis 81 of the Transmission side pump arranged in the right section 30a of the case and in the left section 30b of the case. Likewise, as shown in FIG. 4 and 6, the three sections of the box, which are the lower section 20b of the crankcase, the left section 30b of the box and the right section 30a of the box, are fastened and fixed in the direction of the width of the vehicle around the Pump shaft 101 with various bolt members 91.

As shown in FIG. 2 to 4, 6 and 7, an oil sump unit 38 on the transmission side for storing the oil supplied to the transmission 60 by the oil pump 80 on the transmission side is formed in the transmission case 30 . As shown in FIG. 7, this oil sump unit 38 on the transmission side is provided to close an opening 30d from below. The opening 30d is formed at the bottom of the left section 30b of the box between the three sections 30a to 30c left terminal of the box that constitute the transmission box 30. In other words, the opening 30d of the left section 30b of the case integrally formed as a section of the box is closed by the oil sump unit 38 on the side of the transmission integrally formed.

Thus, the tight seal between a coincident surface 30e around the opening 30d at the lower end of the left section 30b of the box and a coincident surface 38a at the upper end of the crankcase unit can be achieved safely and easily 38 of transmission side oil. In the left section 30b of the box a through hole 30f is formed in a portion of a wall that divides the transmission chamber 31 from the opening 30d, and a through hole 30g is formed in a portion of a wall that divides the exit chamber 32 with respect to opening 30d. As a result, the lubricating oil supplied to the transmission chamber 31 flows down to the oil pan unit 38 on the transmission side from the through hole 30f and the lubricating oil supplied to the outlet chamber 32 flows down to the oil pan unit 38 on the transmission side from the through hole 30g.

As shown in FIG. 3, 4 and 6, the oil pan unit 38 on the transmission side of the left section 30b of the housing extends rearward from a position below the pump 80 on the transmission side to the rear end of the left section 30b of the box to the right of the crankcase oil unit 23 on the crankcase side and the crankcase oil reservoir 24 20. Also, as shown in FIG. 2 and 7, the rear terminal portion of the oil sump unit 38 on the transmission side below the output shaft 70 extends to the left through the rear of the oil reservoir 24. As described above, the oil pan unit 38 on the transmission side is formed extending to the right and to the rear of the oil pan unit 23 on the crankcase side and the oil reservoir 24 to ensure a Sufficient oil storage capacity.

As shown in FIG. 4, 6 and 7, a control unit 200 for controlling the oil supply to the transmission 60 and to the output shaft 70, is arranged in the oil sump unit 38 on the transmission side. On the other hand, as shown in FIG. 4, an intake flow passage 37a for sucking the oil into the oil pump 80 on the transmission side and a discharge flow passage 37b for discharging oil from the oil pump 80 on the transmission side, they are formed in the pump support section 37 of the transmission side. One end of this intake flow passage 37a is connected to an intake port 80c of the oil pump 80 on the transmission side, and its other end is connected to the control unit 200. One end of the discharge flow passage 37b is connected to a discharge port 80d of the oil pump 80 on the transmission side, and its other end is connected to the control unit. Likewise, as shown in FIG. 4 and 7, a filter 201 for aspirating the oil to the control unit 200 from the oil pan unit 38 on the transmission side extends downward from the control unit 200. An intake section 201a disposed near the bottom of the oil sump unit 38 on the transmission side to aspirate the oil contained therein, is formed in a lower end portion of this filter

201.

As shown in FIG. 4, 5 and 7, an oil flow passage 39a, an oil flow passage step 39b and an oil flow passage 39c are independently formed in the right section 30a of the box. One end of the oil flow passage 39a communicates with the right end of the bearing 33a right of the drive pulley shaft, while its other end communicates with the other portion of the left end surface of the lower side portion of section 30a right of the box (that is, a matching surface arranged on the dividing surface S2). One end of the oil flow passage 39b communicates with the right end of the right bearing 34a of the driven pulley shaft while its other end communicates with another portion of the left end surface of the lower side portion of the right section 30a of the box. One end of the oil flow passage 39c communicates with the right bearing 35a of the output shaft while its other end communicates with another additional portion of the left end surface of the lower side portion of the right section 30a of the case.

On the other hand, as shown in FIG. 4 and 7, three steps 39d to 39f of oil flow are independently formed from each other in the left section 30b of the box. One end of the three steps 39d to 39f of oil flow communicates, respectively, with the positions on the right terminal surface of the left section 30b of the box corresponding to the three steps 39a to 39c of oil flow formed on the left terminal surface of the right section 30a of the box, and its other ends are connected to the control unit 200. As described above, the oil flow steps 39a to 39f are formed through the left section 30b of the case and the right section 30a of the case to be connected with the right bearing 33a of the drive pulley shaft , with the right bearing 34a of the driven pulley shaft, with the right shaft 35a of the output shaft and with the control unit 200 of the transmission case 30.

As shown in FIG. 5 to 7, hollow sections 62a, 64b and 70f are respectively formed within the axis 62 of the drive pulley, the axis 64 of the driven pulley, and the output axis 70 to extend respectively along its axial centers P2, P3 and P4 to communicate with their right ends. Likewise, the oil flow steps 62b, 64c and 70g that respectively extend outward in radial direction from the hollow sections 62a, 64b and 70f to communicate with the peripheries of the shaft 62 of the drive pulley, of the shaft 64 of the driven pulley and the output shaft 70 are formed within the axis 62 of the drive pulley, the axis 64 of the driven pulley and the output shaft 70. Likewise, the flow passages 61e, 63e are respectively formed in the removable sheave 61b of the drag side and in the removable sheave 63b of the dragged side. The oil flow passage 61e connects the hollow section 62a of the drive pulley shaft 62 with the oil housing section 61c on the drive side, and the oil flow step 63e connects the hollow section 64b of the drive shaft 64 the pulley pulled with the oil housing section 63c on the dragged side.

Therefore, it is possible to supply oil for hydraulic control to the oil housing section 61c of the drag side and the oil housing section 63c of the dragged side by means of the drag of the oil pump 80 of the transmission side. More specifically, once the shaft 81 of the transmission side oil pump rotates in conjunction with the crankshaft 40 thereby dragging the transmission side 80 oil pump, the oil stored in the crankcase unit 38 from the transmission side it flows through the control unit 200 through the filter 201 and continues to be carried inside the oil pump 80 from the transmission side through the inlet flow passage 37a (see FIG . 4). The oil drawn into the oil pump 80 on the transmission side is discharged from it, flows into the control unit 200 through the discharge flow passage 37b (see FIG. 4) and, then, it continues to flow into the steps 39d to 39f of oil flow formed in a left section 30b of the box.

At this time, the control unit 200 can independently adjust the opening and closing of the control valves (not shown) that are respectively provided in the connection portions existing between the control unit 200 and the steps 39d to 39f of oil flow formed in the left section 30b of the box. More specifically, for example, the control unit 200 opens the control valve of the oil flow passage 39d that communicates with the shaft 62 of the drive pulley and closes the control valve of the oil flow step 39e that communicates with the shaft 64 of the pulley driven in order to increase the effective diameter of the drive pulley 61. As a result, the oil is selectively supplied by pressure from the control unit 200 to the oil housing section 61c of the drive side of the drive pulley 61 through the oil flow passage 39d of the left section 30b of the box and of the oil flow passage 39a in the right section 30a of the box. Then, the removable sheave 61b on the drive side (see FIGS. 5 and 6) slides to the right to increase the effective diameter of the drive pulley 61.

Likewise, the oil stored in the oil pan unit 38 on the transmission side is used both for the purpose of hydraulic control of the transmission 60 and for the lubrication of the transmission 60, the output shaft 70 and the shaft 71 of coupling. That is, in engine 2, the only oil pump 80 on the transmission side supplies the oil from the oil pan unit on the transmission side to the transmission 60 for hydraulic control, as described above and, It also supplies the oil from the oil sump unit 38 on the transmission side to the transmission 60, the output shaft 70 and the coupling shaft 71 for lubrication. An oil flow passage (not shown) is formed in the transmission case 30 with the only one of its ends communicating with both the transmission chamber 31 and the outlet chamber 32. In this way, the lubrication oil supplied under pressure from the oil pump 80 on the transmission side can be supplied to the transmission chamber 31 and the outlet chamber 32 through the oil flow passage.

FIG. 8 is an explanatory view showing the relative positions of the axes arranged in parallel within the motor case 2a seen from the left side of the motor 2. More specifically, FIG. 8 shows an axis 47b of the compensator 47, the crankshaft 40, the axis 62 of the drive pulley, the axis 64 of the driven pulley, the output shaft 70 and the axis 81 of the transmission side pump. An address indicated by an arrow F in FIG. 8 is a front direction of the motor 2.

As described above, because the shaft 62 of the drive pulley and that the clutch shaft 53 are coaxially coupled to constitute the complex main shaft 100 (see FIG. 5), the clutch shaft 53 and the shaft Main complex 100 are placed in the same position as the axle 62 of the drive pulley in FIG. 8. Also, because the shaft 81 of the transmission side pump and that the shaft 85 of the crankcase side pump are coaxially coupled to constitute the complex pump shaft 101 (see FIG. 6), the shaft 85 of the pump on the crankcase side and the complex shaft 101 of the pump are located in the same position as the shaft 81 of the pump on the transmission side in FIG. 8.

Likewise, FIG. 8 shows: the dividing surface S1 of the crankcase passing through the axial center P6 of the shaft 47b of the compensator and the axial center P1 of the crankshaft 40; a flat surface S4 (horizontal surface) showing a horizontal direction of the engine 2 when mounted on the motorcycle 1; a flat surface S5 passing through the axial center P1 of the crankshaft 40 and the axial center P4 of the output shaft 70; a flat surface S6 passing through the axial center P1 of the crankshaft 40 and which is perpendicular to the flat surface S5; a flat surface S7 that passes through the axial center P4 of the output shaft 70 and that is perpendicular to the flat surface S5; a flat surface S8 that passes through the axial center P2 of the axis 62 of the drive pulley and is parallel to the dividing surface S1 of the crankcase 20; and a flat surface S9 that passes through the axial center P2 of the axis 62 of the drive pulley and is perpendicular to the flat surface S5.

For example, in the motor box 2a shown in FIG. 2, the horizontal surface S4 extends over an extended line of the flat bottom surfaces of the crankcase oil unit 23 on the crankcase side, the oil reservoir 24, and the crankcase unit 38 on the transmission side. The horizontal surface S4 is also a terminal surface located at the bottom of the motor case 2a.

As described above, the engine 2 includes: the crankshaft 40 driven by a reciprocating movement of the pistons (not shown) housed in the section 2b of the cylinders (see FIG. 2); the shaft 62 of the drive pulley driven by rotation of the crankshaft 40; shaft 64 of the driven pulley driven by rotation of the shaft 62 of the drive pulley; the output shaft 70 driven by rotation of the shaft 64 of the driven pulley, and the shaft 81 of the pump on the drive side driven by rotation of the crankshaft 40. Also, the crankshaft 40, the axis 62 of the drive pulley , the shaft 64 of the driven pulley, the output shaft 70 and the shaft 81 of the transmission side pump are formed separately from each other and are arranged in parallel with each other.

As described above, the complex shaft 101 of the pump comprised of shaft 81 of the pump on the transmission side and shaft 85 of the pump on the crankcase side is coupled to section 51 upstream of the clutch by middle of intermediate gear 86 as an idle gear. This main complex shaft 101 can be coupled to a shaft upstream of the clutch 50 in terms of transmission of the drag force by means of the idle gear.

The oil pump 82 on the crankcase side for supplying oil to the crankcase 20 is fixed to the complex shaft 101 of the pump comprising the shaft 81 of the pump on the transmission side and the shaft 85 of the pump on the crankcase side.

In addition to the above configuration, in the motor case 2a, the shaft 62 of the drive pulley and the shaft 64 of the driven pulley are arranged between the crankshaft 40 and the output shaft 70 and are arranged above the surface S5 flat. More specifically, both the axial center P2 of the axis 62 of the drive pulley and the axial center P3 of the axis 64 of the driven pulley are located between the flat surface S6 and the flat surface S7 and are located above the surface S5 flat.

The shaft 81 of the transmission side pump is disposed between the crankshaft 40 and the output shaft 70. More specifically, the axial center P5 of the shaft 81 of the transmission side pump is located between the flat surface S6 and the flat surface S7.

Likewise, the axis 81 of the pump on the transmission side is arranged closer to the side of the flat surface S5 than the axis 62 of the drive pulley and that the axis 64 of the driven pulley. More specifically, the axial center P5 of the shaft 81 of the transmission side pump is located below the flat surface S5.

However, for example, the axial center P5 of the shaft 81 of the transmission side pump may be located above the flat surface S5 and be located closer to the flat surface S5 than a flat surface (not shown) that It is placed in parallel with the flat surface S5 and passes through an axial center P2 of the axis 62 of the drive pulley and the axial center P3 of the axis 64 of the driven pulley.

As described above, the shaft 81 of the transmission side pump is disposed in a position surrounded by the crankshaft 40, the shaft 62 of the drive pulley, the shaft 64 of the driven pulley and the output shaft 70 in a side view of the engine 2, as shown in FIG. 8. Therefore, the reduction of the size of the motor 2 is achieved not only in its width direction but also in the longitudinal direction and in the vertical direction.

The shaft 64 of the driven pulley is disposed below the axis 62 of the drive pulley. More specifically, the axial center P3 of the shaft 64 of the driven pulley is located below the flat surface S8.

The complex shaft 101 of the pump including the shaft 81 of the transmission side pump is located behind the shaft 62 of the drive pulley. More specifically, the axial center P5 of the complex pump shaft 101 is located behind the flat surface S9.

The complex main shaft 100 including the axis 62 of the drive pulley is rotatably supported by the upper section 20a of the housing above the dividing surface S1 of the crankcase 20. That is, the axial center P2 of the complex main axis 100 It is located above the dividing surface S1.

Likewise, the complex shaft 101 of the pump, which includes the shaft 81 of the pump on the transmission side is supported in rotation by the lower section 20b of the crankcase below the dividing surface S1 of the crankcase 20. That is, the P5 axial center of the pump complex shaft 101 is located below the dividing surface S1.

As described above, the engine 2 has two shafts coupling the crankcase 20 to the transmission case 30, that is, the complex main shaft 100 and the complex shaft 101 of the pump. The complex main shaft 100 is supported so that its axial center P2 is located above the dividing surface S1 and the complex shaft 101 of the pump is supported so that its axial center P5 is located below the dividing surface S1. Therefore, in addition to increasing the stiffness of the crankcase 2a of the engine, the length of the engine 2, especially in the width direction and in the longitudinal direction, can be effectively reduced.

Next, a second aspect of the motor 2 will be described in accordance with this embodiment with reference to FIG. 9 to 15. In the description that follows as in FIG. 9 to 15, the same components used in the example mentioned above shown in FIG. 1 to 8 are indicated by the same numeric references and their detailed description will be omitted. Likewise, with respect to the parts of the components equal to those of the example mentioned above shown in FIG. 1 to 8 its representation and graphic description will be omitted.

FIG. 9 is a plan view of motorcycle 1. This motorcycle 1 is equipped with the same engine 2 as shown in FIG. 1 and, as shown in FIG. 9, is also equipped with a seat 5 with the front seat section 5a and the rear seat section 5b, the central cover 12c extending forward while leaning upward from the position below the front end of the seat 5 , a pair of left and right footrests 12e having a pair of flat left and right surfaces 12f on which the driver sitting on the front seat section 5a places the right and left feet, for example.

Likewise, FIG. 9 shows a line C1 (center line of the body) indicating the center of the motorcycle 1 in the width direction of the vehicle. The center line C1 of the body is a straight line that passes through the center of the front wheel 3 in the direction of the width of the vehicle and the rear wheel in the direction of the width of the vehicle in a state in which the wheel 3 front and rear wheel 4 are linearly arranged for motorcycle 1 to travel in a straight line.

FIG. 10 is a view of the left side of the engine case 2a. FIG. 11 is a view of the right side of the crankcase 2a of the engine. FIG. 10 and 11 show the engine case 2a in a state in which the crankcase cover members 20c, 20d are fixed to cover the sides of the crankshaft 40 in the vehicle width direction.

As shown in FIG. 10, this engine case 2a includes a fixing piece 103 which is arranged through the three sections of the case, which are the upper section 20a of the case and the lower section 20b of the crankcase 20 and the left section 30b of the transmission box 30 and is secured and fixed by bolt members with each of the three members of the box. The three sections of the housing referred to, are also integrally coupled with each other with this fixing piece 103. Therefore, the rigidity of the motor housing 2a, as a whole, is increased more effectively.

FIG. 12 is a view of the engine box 2a. FIG. 13 is a bottom view of the engine box 2a. FIG. 13 shows an axial center P1 of the crankshaft 40, the axial center P2 of the axis 62 of the drive pulley, the axial center P3 of the axis 64 of the driven pulley, the axial center P4 of the output shaft 70, and the axial center P5 of the shaft 81 of the transmission side pump in an assumption that the motor case 2a is seen from below.

FIG. 14 is a sectional view of the engine 2 that is cut along the dividing surface S1 of the crankcase 20 and is seen from the top of the dividing surface S1. FIG. 15 is a sectional view of the engine case 2a taken along the line XV-XV (that is, a center line C2 of the engine) shown in FIG. 14. FIG. 14 shows a line (center line of the engine) C2 indicating the center of the engine in the width direction of the vehicle. The center line C2 of the engine is a line passing through a center point of an intermediate pair of the arms 42b and perpendicular to the axial center P1 of the crankshaft 40 in a direction along the axial center P1 (that is, a longitudinal direction of the crankshaft 40). Likewise, this central line C2 of the motor is parallel to the central line C1 of the bodywork shown in FIG. 9 and is located slightly at a distance from the center line C1 of the body in the vehicle width direction. FIG. 14 shows a coincident surface 20g on which the lower section 20b of the crankcase 20 joins the upper section 20a of the crankcase.

As in the case of the aforementioned shaft, the motor 2 according to the second aspect includes the transmission 60 incorporating the drive pulley 61 and the driven pulley 63 with the metal V belt 65 being wound between them (see FIG 5) and also includes the crankshaft 40, the axle 62 of the drive pulley, the axis 64 of the driven pulley, the output shaft 70 and the axis 81 of the transmission side pump that are aligned in parallel with each other, as shown in FIG. 10 and 11

The shaft 62 of the drive pulley and the shaft 53 of the clutch are axially coupled to constitute the complex main shaft 100, and the shaft 81 of the transmission side pump and the shaft 85 of the crankcase side pump are coaxially coupled to constitute the complex shaft 101 of the pump. Likewise, FIG. 10 shows an axis 86a of the intermediate gear 86 (see FIG. 6) that couples the crankshaft 40 to the complex shaft 101 of the pump.

As shown in FIG. 10 to 13 and 15, the engine 2 is equipped with a crankcase oil unit 110 of the crankcase, which receives the oil supplied to the crankshaft 40, and a crankcase unit 140 of transmission oil, which receives the oil supplied to the transmission 60.

The crankcase oil unit 110 of the crankcase and the transmission oil pan unit 140 are formed separately from each other. More specifically, the crankcase oil unit 110 of the crankcase is provided to hermetically seal an opening (not shown) formed in the lower part of the lower section 20b of the crankcase 20 from below. On the other hand, the transmission oil sump unit 140 is provided to hermetically close the opening 30d (see FIG. 11) formed in the lower part of the lower section 30b of the transmission case box 30 from below. .

The crankcase oil unit 110 of the crankcase has a crankcase oil unit 120 on the crankcase side and an oil tank 130. The crankcase oil unit 120 on the crankcase side is formed in a portion of the lower section of the crankcase 20 located below the crankcase chamber 21 and stores the lubricating oil in the same manner as the oil sump unit 23 of the crankcase side in the example mentioned above. The lubricating oil flows down by the force of gravity from the crankshaft chamber 21 and through the chamber 22 of the crankcase clutch 20 to the interior of the crankcase oil unit 20 on the crankcase side.

The oil pan unit 120 on the crankcase side has a lower surface 121 which includes an intermediate lower surface 121a, a lower left surface 121b and a lower right surface 121c. The intermediate lower surface 121a is disposed in the lower part of the oil sump unit 120 on the crankcase side and extends flatly along the horizontal surface S4. The intake section 25a (see FIG. 15) of the filter 25 disposed in the crankcase oil unit 120 on the crankcase side is disposed above the intermediate lower surface 121a.

Both the lower left surface 121b and the lower right surface 121c are formed so that they are positioned upwards when they move away from the center line C1 of the body in the direction of the width of the vehicle towards the sides (that is the lateral ones in the direction of vehicle width). In other words, the lower left surface 121b is formed so that it tilts upwardly to the left from a left end of the lower intermediate surface 121a, and the lower right surface 121c is formed so that it tilts upwardly to the right from a right end of intermediate lower surface 121a. Likewise, on the lower surface 121, a portion disposed at the front and a portion disposed at the rear of the intermediate lower surface 121 are respectively formed so that they lean upward toward the front and towards the rear from a front end and from a rear end of the intermediate lower surface 121a.

The oil reservoir 130 is formed in another portion of the lower section of the crankcase 20 (a portion of the rear of the crankcase oil unit 120 on the crankcase side) adjacent to the crankcase oil unit 120 on the crankcase side below the clutch chamber 22 and stores lubricating oil transferred from the crankcase oil unit 120 on the crankcase side in the same manner as the oil reservoir 24 of the example mentioned above.

The oil reservoir 130 has a lower surface 131 which includes an intermediate lower surface 131a, a lower left section 131b and a lower right surface 131c. The intermediate lower surface 131a is disposed in the lower part of the oil reservoir 130 and extends flatly along the horizontal surface S4. The intake section 26a (see FIG. 15) of the filter 26 disposed in the oil reservoir 130 is located above the lower intermediate surface 131a.

Both the lower left surface 131b and the lower right surface 131c are formed to be positioned upwards when they move away from the center line C1 of the body in the direction of the vehicle width towards the sides (that is, the lateral ones in the direction of vehicle width). More specifically, the lower left surface 131b is formed so that it tilts upwardly from the left of a left end of the lower intermediate surface 131a, and the lower right surface 131c is formed so that it tilts upwardly to the right from a right end of intermediate lower surface 131a. Likewise, on the lower surface 131, a portion in front of and a portion on the rear of the intermediate lower surface 131a are respectively formed so that they lean upward toward the front and towards the rear from a front and a rear end of intermediate lower surface 131a.

The transmission oil sump unit 140 stores the oil supplied to the transmission 60 by the oil pump 80 on the transmission side in the same manner as the crankcase unit 38 on the transmission side in the example mentioned above. The transmission oil sump unit 140 has a lower surface 141 that includes an intermediate lower surface 141a, a lower left surface 141b and a lower right surface 141c. The intermediate lower surface 141a is disposed in the lower part of the transmission oil sump unit 140 and extends flat above the lower surface between the lower surfaces of the oil sump unit 110 of the crankcase (that is, an intermediate lower surface 121a of the oil sump unit 120 on the crankcase side and the intermediate lower surface 131a of the oil reservoir 130). The intake section 201a of the filter 201 disposed in the transmission oil sump unit 140 is disposed above the intermediate bottom surface 141a (see FIGS. 11 to 13).

As shown in FIG. 10, 11 and 15, the horizontal surface S4 extends along the intermediate lower surface 121a of the crankcase oil unit 120 on the crankcase side and the intermediate lower surface 131a of the oil reservoir 130 as the surfaces of more below the engine box 2a on an extended line of these interior surfaces.

Both the lower left surface 141b and the lower right surface 141c are formed to be positioned upwards when they move away from the center line C1 of the bodywork in the direction of the width of the vehicle towards the sides, (that is the laterals of the steering vehicle). More specifically, the lower left surface 141b is formed so that it slopes upwardly to the left from a left end of the lower intermediate surface 141a and the lower right surface 141c is formed so that it tilts upwardly to the right from the end Intermediate lower surface 141a right. Likewise, on the lower surface 141, a portion disposed in front of and a portion disposed at the rear of the intermediate lower surface 141a are respectively formed so that they lean upward toward the front and the rear from a front end and from a rear end of the intermediate lower surface 141a.

The transmission oil sump unit 140 is formed in an L-shaped configuration having a first section 142, which is arranged on the right side with respect to the center line C1 of the body along the metal belt 65 and a second section 143 extending from a portion of the first section 142 on the side of the pulley 63 dragged to the left side with respect to the center line C1 of the body.

In other words, as shown in FIG. 13, the drive belt 61, the dragged belt 63 and the rolled metal belt 65 between the drive pulley 61 and the driven pulley 63 are all arranged on the right side with respect to the center line C1 of the body. Also, in the transmission oil sump unit 140, the first section 142 extending in the longitudinal direction is arranged along the metal belt 65 on the right side with respect to the center line C1 of the bodywork .

Section 143 is arranged in the center line C1 of the body. In other words, the second section 143 extends in the direction of the width of the vehicle from a rear portion of the first section 142 and is arranged from the right side to the left side with respect to the center line C1 of the body. More specifically, the second section 143 is disposed along the output axis 70 below the output axis 70.

As in the example described above, the control unit 200, to control the oil supply to the transmission 60 and to the output shaft 70 is disposed within the transmission oil sump unit 140. The control unit 200 includes a valve mechanism to control the pressure necessary to supply the oil stored in the transmission oil sump unit 140 to the transmission 60.

As shown in FIG. 13, this control unit 200 is formed by adopting an L configuration that corresponds to the L configuration of the transmission oil sump unit 140. More specifically, a portion of the control unit 200 is formed to extend in the longitudinal direction through the interior of section 142 of the transmission oil sump unit 140, and the other portion of the control unit 200 it is formed to extend in the direction of the width of the vehicle within the second section 143.

On the other hand, the crankcase oil unit 110 of the crankcase is formed by adopting the configuration of an L incorporating: a third section 111 (a front portion of the crankcase unit 120 on the crankcase side) which is provided along the longitudinal direction of the crankshaft 40 and a fourth section 112 (a rear portion of the oil sump unit 120 on the side of the crankcase and the oil reservoir 130) which is disposed in a position adjacent to the first section 142 of the crankcase unit 140 transmission oil.

That is, the third section 111 is composed of a portion facing the rear end of the intermediate lower surface 121a of the crankcase oil unit 120 on the crankcase side. This third section 111 extends in the direction of the width of the vehicle from the left side to the right side with respect to the center line C1 of the body in front of the first section 142 and the second section 143 of the crankcase unit 140 of Transmission oil

The fourth section 112 is comprised of a portion located at the rear of the rear end of the intermediate lower surface 121a of the oil sump unit 120 on the crankcase side and the oil reservoir 130. This fourth section 112 extends in the direction of the width of the vehicle from the left side to the right side with respect to the center line C1 of the body, on the left side of the first section 142 and in front of the second section 143 of the transmission oil sump unit 140.

That is, the crankcase unit 120 proper of the oil on the crankcase side is formed by adopting an L configuration and the crankcase oil unit 110 of the crankcase composed of the crankcase oil unit 120 on the crankcase side and the tank 130 of oil that are arranged adjacent to each other are also formed by adopting the L-shaped configuration as a whole.

As described above, a portion of the crankcase oil unit 110 of the crankcase and a portion of the transmission oil pan unit 140 are arranged in parallel with each other, respectively, on the side of the crankshaft 40 and in the shaft side 62 of the drive pulley. More specifically, the entire crankcase oil unit 110 of the crankcase and the second section 143 of the transmission oil crankcase unit 140 are arranged in parallel with each other in the longitudinal direction, respectively, on the side of the crankshaft 40 and on the shaft side 62 of the drive pulley.

Likewise, the crankcase oil unit 110 of the crankcase and the crankcase unit 140 of transmission oil are each formed by adopting the L-shaped configuration that corresponds to each other. In other words, as shown in FIG. 13, the crankcase oil unit 110 of the crankcase and the oil sump unit 140 of the transmission are each formed by adopting the L-configuration so that they fit together below the engine case 2a. More specifically, the fourth section 112 of the crankcase oil unit 110 of the crankcase and the first section 142 of the transmission oil pan unit 140 are arranged to overlap one another in the direction of the width of the vehicle. Therefore, the capacities of both the crankcase oil unit 110 of the crankcase and the transmission oil pan unit 140 can effectively be secured in a limited space.

As described above, the left end of the crankshaft 40 is covered with the cover member 20c that is disposed on the left side surface of the crankcase 20, and the right end of the crankshaft 40 is covered with the cover member 20d that is arranged on the right side surface of the crankcase 20 (see FIG. 5). The length of the crankcase oil unit 110 of the crankcase in the width direction of the vehicle and the length of the transmission oil pan unit 140 in the direction of the width of the vehicle are both within a range of length between a surface S10 passing through the left end of the left member 20c of the crankcase cover 20 in the width direction of the vehicle and is perpendicular to the axial center P1 of the crankshaft 40 and a surface S11 passing through the right end of the right crankcase cover member 20d 20 in the direction of the width of the vehicle and is perpendicular to the axial center P1 of the crankshaft 40. In other words, both the width of the crankcase oil unit 110 of the crankcase (the length between the end left of the crankcase oil unit 110 from the crankcase to its right end) and the width of the transmission oil pan unit 140 (the length between the left end ierdo of the transmission oil sump unit 140 and its right end) are within a range of the width of the engine case 2a.

The transmission oil sump unit 140 is arranged below the transmission case 30. The rear end 144 of the transmission oil sump unit 140 is located further back than a rear end 30h of a portion of the transmission case 30 covering the rear part of the driven pulley 63. Likewise, as described above, the transmission case 30 is composed of three sections 30a, 30b, 30c left terminal of the case which can be divided in each section by the dividing surfaces S2, S3 (see FIG. 5) which are perpendicular to the axial center P2 of the shaft 62 of the drive pulley. Likewise, as shown in FIG. 11, the transmission oil sump unit 140 is provided to close the opening 30d from below, and the opening 30d is formed below the bottom of the left section 30b of the housing between the three sections 30a, 30b, 30c left terminal of the box constituting the transmission box 30.

Here, as shown in FIG. 10 and 11, a lower terminal portion 30i of the left section 30b of the box is formed to project towards the rear, so that its rear end is located further back than the rear end 30h of a portion covering the rear of the pulley 63 dragged. Also, the transmission oil sump unit 140 is provided to hermetically close the lower terminal portion 30i of the left section 30b of the case, which projects to the rear, from below. As a result, the rear end 144 of the transmission oil sump unit 140 is disposed further back than the rear end 30h of the portion of the transmission case 30 covering the rear part of the driven pulley 63.

The width of the transmission oil sump unit 140 in the longitudinal direction of the crankshaft 40 is longer than the width of the oil sump unit 110 of the crankcase in the longitudinal direction of the crankshaft 40. Also, the lower surface 141 of the transmission oil sump unit 140 is located higher than the lower surface of the crankcase oil sump unit 110 (that is, the bottom surface 121 of the oil sump unit 120 on the crankcase side and the lower surface 131 of the oil tank 130). On the other hand, the engine 2 is a poly-cylindrical engine that incorporates three cylinders, and three 2d, 2e, 2f, exhaust pipes leave section 2b of the cylinders. More specifically, as shown in FIG. 10 and 11, each of the three exhaust pipes 2d, 2e, 2f extends downward and backward from a front side surface of the cylinder unit 2b.

Likewise, as shown in FIG. 10, the two left exhaust pipes 2d, 2e extend backward on the left side of the crankcase 20, and as shown in FIG. 11, the right exhaust pipe 2f extends backward on the right side of the crankcase 20.

In the engine 2, the two left exhaust pipes 2d, 2e can be arranged on the left side of the crankcase oil unit 110 whose width is reduced, and the right exhaust pipe 2f can be arranged on the right side of the crankcase unit 110 of the crankcase oil. Also, in the engine 2, these three exhaust pipes 2d, 2e, 2f can be arranged together below the transmission oil sump unit 140 whose height is reduced.

As shown in FIG. 14 and 15, the engine 2 includes an oil unit 300 incorporating an oil filter 300a for filtering oil and a coolant 300b of the oil for cooling the existing oil in the front terminal portion of the crankcase 20. It is preferred that the unit 300 of oil is arranged on the front side of the body of the vehicle while exposed to the exterior as described above from the viewpoint of the maintainability of the oil unit 300 and the cooling capacity of the oil cooler 300b.

The oil filter 300a and the refrigerator 300b are each shaped as a cylindrical member. A circular end surface disposed on the rear side of the oil filter 300a is connected to a circular end surface disposed on a front side of the oil cooler 300b. They are then coupled together to constitute the integrated oil unit 300.

An oil flow passage member 301 is inserted into this oil unit 300. A hollow portion formed within this oil flow passage member 301 forms the same oil flow passage 28b shown in FIG. 2.

The oil unit 300 is arranged to be positioned as far up and back as possible. More specifically, as shown in FIG. 14, a central portion 20f disposed in the front terminal portion of the crankcase 20 in a direction along the axial center P1 of the crankshaft 40 is shaped to be indented backwards.

Likewise, the oil unit 300 is provided to project forward from the central portion 20f, which is indented backward, into the crankcase 20. That is, the oil unit 300 is arranged in front of the central cylinder in the direction of the width of the vehicle between the three cylinders included in the engine 2. More specifically, as shown in FIG. 14, the oil unit 300 is arranged in front of the pair of crank arms 42b, which is provided in the center in a direction along the axial center P1 of the crankshaft 40, between the three pairs of the arms 42a, 42b , 42c of the crankshaft provided inside the crankshaft 40.

If the engine 2 is a poly-cylindrical engine with three or more cylinders, the position of the oil unit 300 in the longitudinal direction of this crankshaft 40 is not limited by an extension of a cylinder placed in the center in its longitudinal direction. For example, it can also be located within an extension of one or more cylinders except the one placed at both ends.

As shown in FIG. 14, the engine 2 includes the compensator 47 arranged in front of the crankshaft 40. More specifically, as shown in FIG. 8, this compensator 47 is arranged in parallel with the crankshaft 40 in front of the crankshaft 40 so that the axial center P6 of its axis 47b is located on the dividing surface S1 of the crankcase 20.

The shaft 47b of the compensator is supported in rotation by the crankcase 20. More specifically, as shown in FIG. 14, a left terminal portion of the shaft 47b of the compensator is supported by a shaft support section 47a disposed on the left side of the crankcase 20 by means of a needle bearing. The right terminal portion thereof is supported by the shaft support section 47a disposed on the right side of the crankcase 20 by means of a ball bearing.

The compensator 47 incorporates a pair of weights 47c, 47d right and left of the compensator arranged on both sides of the axis 47b of the compensator. More specifically, as shown in FIG. 14, the left weight 47c of the compensator is provided on the right side of the left axis support section 47a, and the right weight 47d of the compensator is provided on the right side of the right axis support section 47a.

On the shaft 47b of the compensator, a gear 47e is arranged to drive the shaft 47b of the compensator in conjunction with the crankshaft 40 adjacent to the left side of the right weight 47d of the compensator by means of the right section 47a of the shaft. This gear 47e meshes with a gear arranged on the periphery of the right arm 42c of the crankshaft disposed in the right pair 42c of the crankshaft arms of the crankshaft 40. The shaft 47b of the compensator is coupled to the crankshaft 40 by means of the gear 47e and is pulled by the rotation of the crankshaft 40.

The left weight 47c of the compensator and the right weight 47d of the compensator are respectively arranged on the left side and on the right side of the oil unit 300. In other words, as shown in FIG. 14, the left weight 47c of the compensator and the right weight 47d of the compensator are respectively arranged on the left side and on the right side of the central portion 20f of the crankcase 20.

The oil cooler 300b as the rear portion of the oil unit 300, the left weight 47c of the compensator and the right weight 47d of the compensator are linearly arranged to overlap each other in the longitudinal direction of the crankshaft 40. With said configuration, in the engine 2, the oil unit 300 may be arranged below and at least partially behind the crankshaft 40 while the compensator 47 is provided in front of the crankshaft 40.

As shown in FIG. 15, this oil unit 300 extends forward while tilting down. On the other hand, the dividing surface S1 of the crankcase 20 also extends forward while tilting down. An angle A1 formed by this dividing surface S1 and the horizontal surface S4 is maintained in a predetermined range of 25 degrees to 45 degrees, for example.

On the contrary, a line that passes through the center of the fixing surface S14 on which the oil filter 300a is fixed to the oil cooler 300b and is perpendicular to the fixing surface S14 (that is, a central line C3 of the oil unit 300) extends forward while leaning to be located close to the dividing surface S1 of the crankcase 20. More specifically, an angle A2 formed by this center line C3 of the oil unit can be adjusted by approximately 10 degrees and a flat surface 15 that passes through the center of the fixing surface S14 and is in parallel with the dividing surface S1.

As a result, as shown in FIG. 15, the oil unit 300 is arranged so that its lower end is positioned higher than the lower end of the crankcase oil unit 110 (that is, the horizontal surface S4 shown in FIG. 15) . As described above, the oil unit 300 may be arranged in a position close to the crankshaft 40 of the engine 2.

In the engine 2, the section 2b of the cylinders is provided to lean forward with respect to the dividing surface S1 of the crankcase 20. In other words, as shown in FIG. 15, a line (center line of the cylinders) D1 along a longitudinal direction of the section 2b of the cylinders (a direction in which the pistons move reciprocatingly) leans more forward than a line D2 perpendicular to the dividing surface S1 of the crankcase 20. More specifically, an angle A3 formed by the central line D1 of the cylinders and the perpendicular line D2 may be equal to or greater than 25 degrees. As a result, an angle A4 formed by the center line D1 of the cylinders and a line D3 perpendicular to the horizontal surface S4 may be equal to or greater than 60 degrees in the engine

2.

As shown in FIG. 15, the shaft 47b of the compensator is disposed above a horizontal surface S12 that crosses a lower end of a distance Q1 of the crankshaft 40 which includes the arms 42 of the crankshaft. Likewise, a distance Q2 of the pair of weights 47c, 47d left and right of the compensator is arranged below a horizontal surface S13 that crosses the axial center P1 of the crankshaft 40.

It is possible, in the engine 2, to effectively reduce its overall vertical length with said configuration by: the provision of a crankcase 20 whose dividing surface S1 is inclined; the control of the height of the section 2b of the cylinders while arranging the shaft 47b of the compensator in front of the crankshaft 40 on the dividing surface S1; and the arrangement of the oil unit 300 above the lower end of the crankcase oil unit 110 of the crankcase.

As shown in FIG. 15, a free space disposed between an oil level surface L1 stored in the crankcase oil unit 120 on the crankcase side and the compensator 47 is sufficiently secured in the engine 2. Therefore, it is possible to effectively reduce the loss of the drag force preventing the weights 47c, 47d of the compensator from being soaked in the oil of the oil sump unit 120 on the side of the crankcase. FIG. 15 also shows a level surface L2 of the oil tank 130.

In the engine 2, the crankshaft 40, the complex main shaft 100, the shaft 64 of the driven pulley, the output shaft 70 and the complex shaft 101 of the pump are formed separately from each other and are arranged in parallel with respect to each other. to others. Therefore, it is possible to shorten the length of the engine 2 in the direction of the width of the vehicle and thereby reduce the size of the engine 2.

The engine according to the present invention may be an engine equipped with one or more cylinders. However, it is preferred that the engine according to the invention be a multi-cylinder in-line engine and it is also preferred that the engine be a motor with three or more in-line cylinders. Likewise, the oil pump 80 on the transmission side and the oil pump 80 on the crankcase side (sweeping pump 83, feed pump 84) are not limited to trocoidal pumps, and, at least partially, can be Other type of oil pumps.

As described above, a compact motor can be manufactured with the invention. Therefore, the engine according to the invention is indicated for a vehicle of the astride type with a limited space for mounting an engine, such as a motorcycle.

As described above, the engine 2 includes: the crankshaft 40; the transmission case 30 to accommodate the transmission 60 incorporating the drive pulley 61 and the driven pulley 63; the clutch 50 arranged outside the transmission case 30 between the crankshaft 40 and a drive shaft of the pulley (the shaft 62 of the drive pulley) to drive the drive pulley 61 and capable of connecting or disconnecting the transmission of the drag force from the crankshaft 40 towards the drive shaft of the pulley; an oil pump (the oil pump 80 on the transmission side) housed in the transmission case 30 to supply oil to the transmission 60; and a drive shaft of the pump (the shaft 81 of the pump on the transmission side, the complex shaft 101 of the pump) provided separately from the drive shaft of the pulley and extending outside the housing 30 and to drive the oil pump in conjunction with the crankshaft 40 regardless of the connection or disconnection of the transmission of the drag force by the clutch 50. That is, the engine includes: a transmission that incorporates a drive pulley and a pulley pulled; a drive shaft of the pulley to drive the drive pulley; a crankshaft aligned in parallel with the drive shaft of the pulley; a clutch provided between the crankshaft and the drive shaft of the pulley and capable of connecting or disconnecting the transmission of the driving force; a rotating shaft aligned in parallel with the crankshaft; a transmission case to house the transmission; a crankcase to accommodate the crankshaft and crankcase; an oil pump housed in the transmission case to supply oil to the transmission; and a pump drive shaft to drive the oil pump with the crankshaft. Let's see, the expression "the pump drive shaft is driven in conjunction with the crankshaft" means that the pump drive shaft is pulled in conjunction with the crankshaft regardless of the connection or disconnection of the transmission of the force of drive by the clutch 50. More specifically, the pump drive shafts (the shaft 81 of the transmission side pump, the complex shaft 101 of the pump) may be coupled to the upstream section of the clutch 50 (section 51 upstream of the clutch) in terms of the transmission of the drag force, or they may be coupled to an axis provided upstream of the clutch 50 of the engine 2 in terms of transmission of the drag force. Therefore, in the engine 2, it is possible to drive the pump shafts (the shaft 81 of the pump on the transmission side, the complex shaft 101 of the pump) in conjunction with the crankshaft 40 and to facilitate the arrangement of the oil flow steps from the oil pump (the oil pump 80 on the transmission side to the transmission 60 despite the configuration in which the clutch 50 is arranged outside the transmission case 30). In other words, when, for example, the clutch 50 is arranged outside the transmission case 30, the arrangement of the oil flow passages is complicated compared to an assumption in which the clutch 50 is disposed within the transmission box 30. However, the arrangement of the oil flow steps in the engine 2 according to the present invention is facilitated by adopting the configuration in which the oil pump (the oil pump 80 on the transmission side) is housed within the transmission box 30 in which the drive axles of the pump (the axis 81 of the pump on the transmission side, the complex axis 101 of the pump) for driving the oil pump, are provided separately from the axis of the pulley drive (the axle 62 of the drive pulley) and are pulled in conjunction with the crankshaft 40 regardless of the connection or disconnection of the transmission of the drag force by the clutch 50.

An oil sump unit (the oil sump unit 38 on the transmission side) for storing oil is provided inside the engine transmission case 30. This further facilitates the arrangement of the oil flow steps from the oil pan unit (the oil pan unit 38 on the transmission side) to the transmission 60.

The transmission box 30 arranged in the engine 2 includes some sections of the box (the right section 30a of the box, section 30b of the box, and the left terminal section 30c of the box) which can be divided between them surfaces (the dividing surface S2, the dividing surface S3) perpendicular to the axial center P2 of the drive pulley 61 (that is, the axial center P2 of the axis 62 of the drive pulley). The oil pan unit (the oil pan unit 38 on the transmission side) is formed separately from the sections of the case and is arranged to close the opening 30d formed in one of the sections of the case (the 30b left of the box). With the configuration set forth, it is possible to facilitate a secure seal between a portion of the transmission case 30 where the opening 30d and the oil pan unit (the oil pan unit 38 on the transmission side) is formed.

The oil pump (the oil pump 80 on the transmission side) disposed within the engine 2 supplies oil to the transmission 60 for the hydraulic control of the transmission 60 as well as for the lubrication of the transmission 60 of the output shaft 70 and of coupling shaft 71. With the above configuration, it is possible to carry out the hydraulic and lubrication control with a common oil pump (the oil pump 80 on the transmission side). Therefore, it is possible to reduce the number of components of the engine 2 and thereby reduce the size of the engine 2.

In the engine 2, the oil pump (the oil pump 82 on the crankcase side) for supplying oil to the engine section (the section arranged in the clutch 50 and upstream of the clutch 50 within the transmission step of the driving force of the engine 2, such as the crankshaft 40, the clutch 50, and the section 2b of the cylinders) is fixed to the drive shaft of the pump (the complex shaft 101 of the pump). That is, the oil pump for supplying oil to the crankcase 20 is fixed to the drive shaft of the pump. With the above configuration, it is possible to drag the oil pump for transmission 60 (the oil pump 80 on the transmission side) and the oil pump for the engine section (the oil pump 82 on the crankcase side) by the common drive shaft (the complex shaft 101 of the pump). Therefore, it is possible to reduce the number of components of the engine 2 and thereby reduce the size of the engine 2.

The crankshaft 40, the drive shaft of the pump (the complex shaft 101 of the pump) and a rotating shaft of the clutch 50 (the shaft 53 of the clutch) are aligned in parallel with each other inside the engine 2. With the arrangement exposed, it is possible to reduce the size of the engine 2 in one direction along the crankshaft 40 and thereby reduce the size of the engine 2. It is also possible to arrange the drive shaft of the pump (the complex shaft 101 of the pump) in an appropriate position regardless of an axis 50 arrangement.

The pump drive shafts (the shaft 81 of the transmission side pump, the complex shaft 101 of the pump) are provided separately from the crankshaft 40 and are connected to a section upstream of the clutch 50 (the section 51 upstream of the clutch) in terms of transmission of the drag force. With the exposed structure, the pump drive shafts are driven in conjunction with the crankshaft 40 to drive the oil pump 80 from the transmission side irrespective of the connection or disconnection of the drag force transmission by the pump 50. These pump drive shafts are not limited to those connected to the upstream portion of the clutch 50, but can also be connected to a shaft provided upstream of the clutch 50 in terms of the transmission of the force of engine drag 2.

The oil pump (the oil pump 80 on the transmission side) is arranged within a width range of either the drive pulley 61 or the driven pulley 63. In other words, the oil pump for supplying oil to the transmission is arranged between the oil sump unit and either the drive pulley or the driven pulley and, more specifically, it is arranged within a width range of at less a pulley between the drive pulley and the driven pulley below a flat surface that crosses the axial center of the drive pulley shaft and that of the drag pulley shaft. This further facilitates the arrangement of the oil flow passages from the oil pan unit 80 on the transmission side to the interior of the transmission 30.

Description of the Numerals and Reference Symbols

1: motorcycle

2: engine

2a: engine box 2b: cylinder section

3: front wheel

4: rear wheel

5: seat

6: handlebar

7: front fork

8: address line

9: drive shaft

10: silencer

11: articulation axis

12: body cover

13: cylinder block

14: cylinder head

15: cover

20: crankcase 20a: upper section of crankcase 20b: lower section of crankcase

21: crankshaft chamber

22: clutch chamber 22a: left clutch shaft bearing 22b: intermediate clutch shaft bearing 22c: right clutch shaft bearing

23: crankcase oil pan unit

24: oil tank 29a: right pump support section 29b: left pump support section 29c: left crankcase pump bearing 29d: right crankcase pump insert section

30: transmission box 30a: right section of the box 30b: left section of the box 30c: left terminal section of the box 30d: opening

31: transmission chamber

32: output chamber 33a: right drive bearing on the drive side pulley shaft 33b: left drive bearing on the drive side pulley 34a: right drive on the drive side pulley 34b: left drive on the pulley shaft dragged side

37: support section of the transmission side pump 37c: insertion section of the transmission side pump

38: Transmission side oil pan unit

40: crankshaft

50: clutch

53: clutch shaft

60: transmission

61: drive pulley

62: drive pulley shaft

63: pulley pulled

64: pulley shaft driven

70: output shaft

71: coupling shaft

80: transmission side oil pump

81: transmission side pump shaft

82: crankcase oil pump

85: crankcase side pump shaft 85a: crankcase side oil pump shaft 85b: cooling water pump shaft

86: intermediate gear

88: gear member

90: clamping hole

91: bolt member

100: complex main axis

101: complex pump shaft

110: crankcase oil sump unit

120: crankcase oil pan unit

130: oil tank

140: transmission oil pan unit

141: lower surface

200: control unit

Claims (2)

1. An engine (2) comprising: a transmission (60) incorporating a drive pulley (61) and a driven pulley (63); a drive shaft (62) of the pulley to drive the drive pulley (61); a crankshaft (40) provided in parallel with the drive shaft (62) of the pulley; a clutch (50) provided between the crankshaft (40) and the drive shaft (62) of the pulley and capable of connecting or disconnect the connection of the drag force; a rotary shaft (100) of the clutch (50) arranged in parallel with the crankshaft (40); a crankcase (20) for housing the crankshaft (40) and the clutch (50); characterized by a transmission box (30) to accommodate the transmission (60), in which the transmission box is coupled to the crankcase; an oil pump (80), which is housed in the transmission case (30), to supply oil to the transmission (60); Y a pump drive shaft (81, 101) for driving the oil pump in conjunction with the crankshaft. 2. The engine according to Claim 1, wherein an oil sump unit (38) for storing oil is provided in the transmission case (30). 3. The engine according to Claim 2, wherein the transmission box (30) includes a plurality of sections (30a, 30b, 30c) of the box that can be divided by a surface (S2, S3) perpendicular to an axial center (P2) of the pulley drive shaft (62), and the unit of Oil sump (38) is formed separately from the plurality of sections (30a, 30b, 30c) of the box and is provided to close an opening (30d) formed in one of the sections (30b) of the box. 4. The engine according to any one of Claims 1 to 3, wherein The oil pump (80) supplies oil to the transmission (60) for hydraulic control of the transmission (60) as well as for the lubrication of the transmission (60). 5. The engine according to any one of Claims 1 to 4, wherein An oil pump (82) for supplying oil to the crankcase (20) is fixed to the drive shaft (81, 101) of the pump. 6. The engine according to any one of Claims 1 to 5, wherein The oil pump (80) for supplying oil to the transmission (60) is arranged within a wide range of either the drive pulley (61) or the driven pulley (63). 7.- A vehicle of the astride type characterized by understanding the motor (2) according to the Claim 1.