JPS6213535B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power transmission device for a motorcycle, which transmits power from a countershaft of a transmission gear mechanism linked to a crankshaft of an engine to a final shaft connected to a rear wheel. be.

Conventionally, in the shaft drive transmission system of a motorcycle, a drive bevel gear is linked to the countershaft of a transmission gear mechanism, and a driven bevel gear provided on a final shaft that is linked to the rear wheel is meshed with this bevel gear, so that the rotation of the countershaft is controlled by the final shaft. It is known that the system was designed to transmit information to

In this regard, the present invention provides a power transmission device for a motorcycle, which has a simple configuration and allows the driving bevel gear, the driven bevel gear, and the final gear case in which these gears are incorporated to be easily assembled. The main purpose is to

In order to achieve this purpose, the present invention
A drive bevel gear that protrudes outside the case through an opening formed in the outer wall of the case is integrally provided at one end of the countershaft of the transmission gear mechanism housed in the transmission case, and this drive bevel gear is connected to the rear wheel. It is meshed with a driven bevel gear that is integrally provided at the end of a series of filament shafts.
In a power transmission device for a motorcycle, a final gear case in which the driving and driven bevel gears are incorporated is fixed to an outer wall of the transmission case, and the final gear case includes:
first and second bearing holders having first and second insertion openings that allow the driving and driven bevel gears to pass therethrough, and first and second bearing holders that are removably fitted into the first and second insertion openings, respectively; The drive and driven bevel gears are rotatably supported in a final gear case via first and second bearings that are fitted and supported by first and second bearing holders, respectively, and the drive and driven bevel gears are fitted on the countershaft. At least one driven gear closer to the drive bevel gear among the driven gear group of the variable speed gear mechanism is formed to have a smaller diameter than the opening in the outer wall of the transmission case.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

A transmission case 1 is integrally formed with the crankcase of an engine mounted on a motorcycle sideways (in a direction in which the crankshaft is perpendicular to the direction of movement of the motorcycle).
A main shaft 2 that is linked to a crankshaft, and a speed change gear mechanism 4 connected to this main shaft 2.
Counter shafts 3 are rotatably mounted in parallel, and are connected to a transmission gear mechanism 4.
The rotation of the main shaft 2 can be transmitted to the countershaft 3 at a predetermined gear ratio by the gear change operation of the mechanism 4.

A drive bevel gear 7 is integrally formed at one end of a countershaft 3 that is rotatably supported by the mission case 1 via ball bearings 5 and 6. It projects out of the transmission case 1 through a bearing hole 9 which is an opening opened to the outside of the transmission case 1, and is supported in a cantilevered manner by the one ball bearing 5. A final gear case 10 is fixed to the outer surface of the outer wall 1a of the transmission case 1 by a plurality of case mounting bolts 11, 11, . . . so as to cover the bearing hole 9. Further, on the joint surface 10b of the final gear case 10 to the outer wall 1a,
A pair of bearing holder halves 13 and 14 are overlapped with each other with a gasket 15 sandwiched between them so as to surround the drive bevel gear 7. In particular, the bearing holder halves 13
is fitted into a first insertion opening 40 formed in the final gear case 10 and having a larger diameter than the drive bevel gear 7. Both bearing holder halves 13 and 14 are fastened to the final gear case 10 with a shim plate 16 in between by a bearing mounting bolt 12 inserted from the outside thereof. One of the ball bearings 5, which is press-fitted into the countershaft 3 in advance, is fitted into the inner peripheral surfaces of the two bearing holder halves 13 and 14. A cylindrical fitting surface 17 is formed on one side of the bearing holder half 14, and this fitting surface 17 is fitted into the bearing hole 9 of the transmission case 1 in a removable manner. Therefore, the final gear case 10 includes both bearing holder halves 1.
3, 14, and by removing the case mounting bolts 11, 11..., the final gear case 10 is integrated with the bearing holder halves 13, 14, the ball bearing 5, and the countershaft 3. It can be removed from the transmission case 1 together with the driven bevel gear 7. The two bearing holder halves 13 and 14 constitute the first bearing holder 41 of the present invention.

A second insertion port 1 having a larger diameter than a driven bevel gear 8, which will be described later, is provided in one end wall of the final gear case 10.
8 is opened, and the final shaft 19 is inserted into the final gear case 10 through this second insertion port 18.
is rotatably mounted on the final gear case 10 via needle and ball bearings 20 and 21. The needle bearing 20 is the final gear case 1
The ball bearing 21 is fitted and supported by a bearing holder portion 10a formed in the second insertion hole 18, and the ball bearing 21 is fitted and supported by a second bearing holder 22 fitted into the second insertion opening 18. At the same time, it is fixed to the end surface of the case 10 on the second insertion port 18 side by a plurality of cover mounting bolts 24, 24, . . . .
A driven bevel gear 8 is integrally formed at the inner end of the final shaft 19, and this gear 8 meshes with the driving bevel gear 7 within the final gear case 10, so that power from the counter shaft 3 is transmitted. There is. Second insertion port 18 of final gear case 10 and final shaft 19
The gap therebetween is oil-tightly sealed by an oil seal 25. A power transmission spline 26 is provided at the outer end of the final shaft 19 outside the final gear case 10, and this power transmission spline 26 is interlocked with the rear wheel via an interlocking mechanism (not shown).

The speed change gear mechanism 4 includes a first to second speed change gear train, and the main shaft 2 includes a first to second speed change gear train.
From left to right in the diagram: 1st speed, 1st speed, 1st speed, 1st speed,
Interlocking gears 27 to 32 of the first speed and second speed systems are supported, respectively, and the countershaft 3 includes, from left to right in FIG.
Driven gears 33 to 3 of the first speed, second speed, and second speed systems
8 is supported, and the driving gears 27 to 32 and driven gears 33 to 38 are respectively meshed with each other.

Also, the drive bevel gear 7 of the countershaft 3
The first part supported by the closer half (left half in Figure 1),
, the driven gears 33, 34, and 35 of the system are all mounted in bearing holes 9 bored in the outer wall of the transmission case 1.
These driven gears 33, 34, 35 can be inserted into and removed from the mission case 1 through the bearing hole 9 while being supported on the countershaft 3.

Next, the operation of one embodiment of the present invention will be explained. When the engine is now operated, the main shaft 2 is rotationally driven, and this rotation is caused by the transmission gear mechanism 4.
is transmitted to the countershaft 3 via. The rotation of the countershaft 3 is controlled by the final shaft 19 via a driving bevel gear 7 which is integral with the countershaft 3 and a driven bevel gear 8 which is integral with the final shaft 19.
is transmitted.

The driving bevel gear 7 integrated with the countershaft 3 and the driven bevel gear 8 meshed with the driving bevel gear 7 are pre-assembled in the final gear case 10, and then the final gear case 10 is inserted into the case mounting bolt 11 from the outside. ... can be connected to the transmission case 1, and when the need for maintenance inside the final gear case 10 arises, it can be integrated with the drive bevel gear 7 by removing the case mounting bolts 11... and the bearing mounting bolts 12... The final gear case 10 can be removed from the transmission case 1 while leaving the countershaft 3 in the transmission case 1, and the maintainability of the final gear case 10 can be improved.

As described above, according to the present invention, one end of the countershaft 3 of the transmission gear mechanism 4 housed in the transmission case 1 is connected to the outside of the case 1 through the opening 9 formed in the outer wall 1a of the case 1. A protruding drive bevel gear 7 is integrally provided, and this drive bevel gear 7 is connected to the final shaft 1 connected to the rear wheel.
In a power transmission device for a motorcycle, the final gear case 10 in which the drive and driven bevel gears 7, 8 are incorporated is connected to the outer wall 1a of the transmission case 1. At the same time as sticking to
The final gear case 10 is provided with first and second insertion ports 40 and 18 that allow the driving and driven bevel gears 7 and 8 to pass therethrough, respectively, and are removably inserted into the first and second insertion ports 40 and 18, respectively. first and second bearing holders 41 and 22 to be fitted;
The driving and driven bevel gears 7 and 8 are rotatably supported in the final gear case 10 via first and second bearings 5 and 21 that are fitted and supported by the first and second bearing holders 41 and 22, respectively. Therefore, both bevel gears 7 and 8 and both bearing holders 41 and 22 are installed inside the final gear case 10.
Both bearings 5 and 21 can be assembled in advance on separate lines, and the power transmission system between the countershaft 3 and the final shaft 19 can be completed at once by simply mounting the assembly on the transmission case 1. This can greatly contribute to improving overall assembly work efficiency. In particular, although the drive bevel gears 7 and 8 are integrated with the countershaft 3 and the final shaft 19, respectively, in order to increase their strength, the first and second insertion openings 40, From 18, same case 10
It can be inserted smoothly without disassembling itself, and at that time, the first and second bearings 5 and 21 are inserted into the first and second bearings via the first and second bearing holders 41 and 22.
Since they are installed in the second insertion ports 40, 18, the trouble of directly fixing the first and second bearings 5, 21 to the final gear case 10 is saved, and as a result,
The work of assembling both bevel gears 7, 8, etc. into the final gear case 10 can also be performed extremely efficiently. Furthermore, the bearing holders 41 and 22
is the dimensional relationship between the bearings 5, 21 and the bevel gears 7, 8, and therefore the dimensional relationship between the bearings 5, 21 and the case insertion port 4.
Bearing 5, regardless of the dimensional relationship with 0, 18.
21 without making the insertion port 4 particularly large.
0,18 can always be attached accurately.

Also fitted on the countershaft 3,
Among the groups of driven gears 33 to 38 of the transmission gear mechanism 4, at least one driven gear 33 to 35 closer to the drive bevel gear 7 is formed to have a smaller diameter than the opening 9 of the outer wall 1a of the transmission case 1.
While the driven gears 33 to 35 are supported on the countershaft 3, the shaft 3 can be inserted into and removed from the mission case 1 through the opening 9, thus improving the efficiency of the insertion and removal work. can contribute to

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a cross-sectional view of FIG. 2, and FIG. 2 is a cross-sectional view of FIG.
It is a line arrow view. DESCRIPTION OF SYMBOLS 1...Mission case, 1a...Outside wall, 3...Countershaft, 4...Transmission gear mechanism, 5, 21...
First and second bearings, 7... Drive bevel gear, 8... Driven bevel gear, 9... Bearing hole as opening, 10...
Final gear case, 40, 18...1st, 2nd
Insertion port, 41, 22...first, second bearing holder, 1
9...Final shaft, 33-38...Driven gear.

Claims (1)

[Claims] 1. A drive bevel gear 7 is integrally provided at one end of the countershaft 3 of the transmission gear mechanism 4 housed in the transmission case 1, and projects out of the case 1 through an opening 9 formed in the outer wall 1a of the case 1. The drive and driven bevel gears 7 and 8 are incorporated in a power transmission device for a motorcycle, in which the driving bevel gear 7 is meshed with a driven bevel gear 8 that is integrally provided at the end of a final shaft 19 connected to a rear wheel. The final gear case 10 is attached to the outer wall 1a of the transmission case 1.
At the same time, the final gear case 1
0, first and second insertion openings 40 and 18 are opened to allow passage of the driving and driven bevel gears 7 and 8, and the bevel gears are removably fitted into the first and second insertion openings 40 and 18, respectively. The driving and driven bevel gears 7 are . A power transmission device for a motorcycle, characterized in that 33 to 35 are formed to have smaller diameters than the opening 9 of the outer wall 1a of the transmission case 1.