JPS6335812B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a multi-cylinder engine for a motorcycle in which an intermediate shaft and a transmission main shaft are arranged in parallel behind a horizontal crankshaft.

(Technical Background of the Invention) In a multi-cylinder engine having a horizontal crankshaft, an intermediate shaft is provided parallel to the crankshaft in order to narrow the overall width of the engine, and the output of the travel drive system is taken from this intermediate shaft. There has always been something that has been done.

In this case, a large-diameter transmission clutch is installed on the transmission main shaft of the travel drive system, and it is necessary to transmit the rotation of the intermediate shaft to the reduction gear of this clutch, so the axial distance between the intermediate shaft and the main shaft must be increased. This resulted in the problem of increasing the size of the engine.

Therefore, a configuration can be considered in which the rotation of the crankshaft is directly transmitted to the main shaft without going through an intermediate shaft. In this case, from the viewpoint of maintainability of the generator, it is desirable to have the engine outer end of the intermediate shaft protrude from the bearing and install the generator on this protruding end. It becomes necessary to make the bearing spacing as large as possible, which causes the problem that the engine becomes larger. In addition, the crankcase side that holds the intermediate shaft is required to have high rigidity and good workability.

(Object of the Invention) This invention was made in view of the above circumstances, and it is an object of the present invention to effectively utilize the space between the bearings even though the interval between the bearings of the intermediate shaft is sufficiently large, and to downsize the engine. It is an object of the present invention to provide a multi-cylinder engine for a motorcycle, in which the generator drive system and the starter transmission mechanism can be easily assembled, and the crankcase has high rigidity and good workability. This is the purpose.

(Structure of the Invention) According to the present invention, the object is to provide an intermediate shaft and a transmission main shaft in parallel behind a horizontal crankshaft, and to connect a generator disposed at the outer end of the engine of the intermediate shaft to a generator drive system. In a multi-cylinder engine of a motorcycle, the multi-cylinder engine of a motorcycle is driven by the crankshaft via the crankshaft, and the transmission main shaft is driven by the crankshaft,
The intermediate shaft is inserted and supported from the generator side by two bearings arranged in the crankcase, and a sprocket and a damper forming the generator drive system are mounted on the intermediate shaft between the two bearings. This is achieved by a multi-cylinder engine for a motorcycle, which is characterized by being provided with a starter transmission mechanism for the engine.

(Example) The present invention will be described in detail below based on the drawings.

FIG. 1 is a configuration diagram of a first embodiment according to the present invention;
FIG. 2 is a side view showing the arrangement of the respective axes, FIG. 3 is a sectional view taken along the line ``--'', and FIG. 4 is a sectional view of the main part. In these figures, reference numeral 1 is a horizontally placed four-cylinder crankshaft, and 2 is a piston. Four pistons 2 are each connected to one crankshaft 1 via connecting rods 3. 4, 4 are a pair of camshafts, and these camshafts 4, 4 are connected to the crankshaft 1.
It is driven by a gear 5 integral with the timing chain 6. Reference numerals 7 and 8 are a transmission main shaft and a sub-shaft forming a transmission, and the transmission main shaft 7, which is arranged in parallel behind the crankshaft 1, is provided with a known wet multi-disc transmission clutch 9 at one end thereof. A damper spring 11 is provided in the casing 10 of this clutch 9.
A large reduction gear 12 is attached through the crankshaft 1, and this gear 12 is driven by a drive gear 13 that is integral with the crankshaft 1. This rotation of the main shaft 7 is caused by the main shaft 7 and the sub-shaft 8.
The rotation of the countershaft 8 is transmitted to the subshaft 8 through a gear group provided in the subshaft 8, and the rotation of the subshaft 8 is
4. The rotation of this shaft 14 is caused by the rotation of this shaft 14.
4 via a bevel gear 16, and this output shaft 15 drives rear wheels (drive wheels) via a propeller shaft (not shown).

20 is an intermediate shaft located behind the crankshaft 1 and above the main shaft 7. This intermediate shaft 20 is the fourth
As shown in the figure, insert two bearings 2 toward the crankcase side.
It is supported by 0A and 20B. That is, the crankcase is divided into upper and lower parts, and the upper crankcase half is integrally molded, and two bearings 20 are mounted on two substantially vertical walls of this crankcase half.
A and 20B are retained. The engine outer end of the intermediate shaft 20 projects from the bearing 20A, and a generator 36, which will be described later, is disposed at this projecting end. Between the bearings 20A and 20B on the intermediate shaft 20, a sprocket 21 and a damper 22 forming a generator drive system, as well as a gear 27 and a one-way clutch 28, which are the transmission mechanism of the starter motor, are mounted. That is, a sprocket 21 is rotatably mounted on the intermediate shaft 20, and one end of this sprocket 21, that is, the end opposite to a generator 36 (described later) with a chain 26 (described later) in between, has an enlarged diameter and is inserted here. Spring damper 2
2 is installed. A member 23 connected to the intermediate shaft 20 by a spline having an involute tooth profile is mounted on one end surface of the sprocket 21, and a plurality of springs 24 are installed in the circumferential direction between the member 23 and the sprocket 21. There is. FIG. 5 is a cross-sectional view taken along the line --- showing a vertical cross section of this spring damper 22. As shown in FIG. The sprocket 21 is driven by a sprocket 25 formed integrally with the crankshaft 1 via a chain 26. The gear 27 is a gear rotatably mounted on the intermediate shaft 20, and the gear 27 and the sprocket 2
1 is connected by a one-way clutch 28. That is, the sprocket 21 is formed with three connecting portions 21a extending in the central axis direction so as to cover a portion of the member 23 (see FIG. 5).
This connecting portion 21a and one-way clutch 28 are connected. 29 is a starter motor, and 30 is a refurbished idle gear between the small gear 31 of the starter motor 29 and the gear 27.

When assembling the intermediate shaft 20, the sprocket 2
1. Align and hold the damper 22, gear 27, one-way clutch 28, etc. between the bearings 20A and 20B, and in this state insert the intermediate shaft 20 from the bearing 20A side so as to pass through these, and insert the tip into the bearing 2.
Just insert it into 0B.

Reference numeral 35 denotes a generator case integrated with the crankcase, one end of the intermediate shaft 20 extending into this case 35, and an alternating current generator 36 is loaded here. That is, a stator 37 is fixed to the inner surface of the case 35, while a rotor 38, which is a heavy rotating body, is fixed to the intermediate shaft 20, and a ring-shaped rotor 38 is fixed to the surface perpendicular to the central axis of the rotor 38. slip ring 3
Two 9's are buried. This slip ring 3
9, 39 is a brush 4 fixed to the case 35
0 and 40 are in sliding contact. 41 is this case 35
It is a cover that is covered by

In this embodiment, the rotation of the crankshaft 1 is transmitted to the sprocket 21 via a chain 26, and then to the intermediate shaft 20 via a spring damper 22 and a member 23 located on the opposite side of the generator 36 with respect to the chain 26. The rotor 38
is transmitted to. At this time, the torque fluctuation of the crankshaft 1 due to the intermittent explosion of each cylinder is absorbed by the chain 26 and the spring damper 22, and the rotor 38 is rotated smoothly. Furthermore, when starting the engine, the rotation of the starter motor 29 is controlled by the idle gear 3.
0, the crankshaft 1 via the gear 27, one-way clutch 28, sprocket 21, and chain 26.
When the engine starts, the rotation of the sprocket 21 becomes faster than the rotation of the gear 27, and the one-way clutch 28 is disengaged.

In this embodiment, since the damper 22 is disposed on the opposite side of the generator 36 across the chain 26, rotation is transmitted to the intermediate shaft 20 at a position far from the generator 36. Therefore, in addition to the damper 22, the damper effect due to the torsion of the intermediate shaft 20 itself can be effectively utilized, and the capacity of the damper 22 can be reduced.

On the other hand, the output of the traveling drive system is directly transmitted from the drive gear 13 of the crankshaft 1 to the large reduction gear 12 without passing through the intermediate shaft 20, and as described above, the output is transmitted directly to the large reduction gear 12, including the damper spring 11, the clutch 9, the main shaft 7, and the subshaft 8. ,
It is transmitted to the rear wheels via the shaft 14 and the output shaft 15.

In this embodiment, as described above, the spring damper 22 is interposed between the sprocket 21 and the generator 36, and the starter motor 29 and the sprocket 21 are connected to each other.
The structure is such that only the one-way clutch 28 is interposed between the two and the spring damper 22 is not interposed therebetween.

In this embodiment, as shown in FIG. 3, if the drive gear 13 is provided at a position other than both ends of the crankshaft 1, the amount of lateral protrusion of the clutch 9 of the main shaft 7 will be reduced, and balance becomes better.

FIG. 6 is a configuration diagram showing a second embodiment of the present invention;
FIG. 7 is a sectional view of a main part thereof, and this embodiment is constructed so that the rotation of the crankshaft is transmitted to the generator via a rubber damper. In these figures, the same parts as in the first embodiment are given the same reference numerals, so their description will not be repeated. In this embodiment, the sprocket 21A is connected to the cylindrical portion 2 of the member 23A.
A rubber damper 22A is rotatably mounted on the sprocket 3B, and a rubber damper 22A is radially loaded with rubber 24A between the sprocket 21A and the member 23A. This rubber damper 22A is located on the opposite side of the generator 36 with the chain 26 interposed therebetween.

FIG. 8 is a sectional view taken along the line --- showing this rubber damper 22A. That is, radial walls 21Aa and 23Aa are formed alternately in the facing portion of the sprocket 21A and the member 23A, and these walls 21
A fan-shaped rubber 24A is loaded between Aa and 23Aa.

Therefore, the rotation of the crankshaft 1 is transmitted to the rotor 38 of the generator 36 via the chain 26, sprocket 21A, wall 21Aa, rubber 24A, wall 23Aa, member 23A, and intermediate shaft 20. Also, the rotation of the starter motor 29 is controlled by the small gear 31 and the idle gear 3.
0, gear 27, one-way clutch 28, member 2
3A, the wall 23Aa, the rubber 24A, the wall 21Aa, the sprocket 21A, and the chain 26.

On the other hand, the output of the drive system is transmitted directly from the drive gear 13 of the crankshaft 1 to the large reduction gear 12, as is clear from FIG.

(Effects of the Invention) As described above, when an intermediate shaft having a generator disposed at one end is supported on the crankcase side by two bearings, even if the distance between both bearings is sufficiently wide, the The sprocket and damper of the generator drive system, as well as gears and one-way clutches that are the rotation transmission mechanism of the starter motor, are placed on the intermediate shaft between the two bearings, so the space between both bearings can be used effectively, and the engine can be made smaller. In addition, the two bearings of the intermediate shaft are held in the crankcase, the starter transmission mechanism etc. are held between both bearings, and the intermediate shaft is inserted from the generator side, so the crankcase has a split surface that crosses these bearings. There is no need to provide Therefore, high rigidity of the crankcase and good workability can be obtained at the same time. The intermediate shaft can be assembled by supporting parts such as the sprocket, damper, and starter transmission mechanism that are held on the intermediate shaft from the opening on the split side of the half body that forms the crankcase, making it possible to downsize the engine. Also, ease of assembly is improved.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a first embodiment according to the present invention, FIG. 2 is a side view showing the arrangement of each axis, FIG. 3 is a cross-sectional view taken along the line, FIG. FIG. 5 is a sectional view taken along the line ``-'', FIG. 6 is a general configuration diagram showing a second embodiment of the present invention, FIG. 7 is a sectional view of essential parts thereof, and FIG. 8 is a sectional view taken along the ``--'' line. DESCRIPTION OF SYMBOLS 1... Crankshaft, 7... Transmission main shaft, 20... Intermediate shaft, 20A, 20B... Bearing, 21... Sprocket, 22, 22A... Damper, 26... Chain, 2
7... Gear, 28... One-way clutch, 36... Generator.

Claims (1)

[Scope of Claims] 1. An intermediate shaft and a transmission main shaft are arranged in parallel behind a horizontal crankshaft, and a generator disposed at the outer end of the engine of the intermediate shaft is driven by the crankshaft via a generator drive system. In a multi-cylinder engine of a motorcycle, the transmission main shaft is driven by the crankshaft, the intermediate shaft is inserted from the generator side into two bearings disposed in the crankcase and is pivotally supported,
A multi-cylinder engine for a motorcycle, wherein a sprocket and a damper forming the generator drive system, and a starter transmission mechanism of the engine are disposed on the intermediate shaft between the two bearings.