JPS604854Y2 - Motorcycle power unit side cover device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a side cover device that is attached to the outer surface of a power unit of a motorcycle.

Conventionally, in motorcycles, a side cover is provided on the side of the power unit, and the entire inner surface of this side cover is equipped with anti-vibration,
It is known that soundproofing elastic bodies are bonded together by gluing or baking, but with such devices, the binding of vibrationproofing and soundproofing materials not only depends on the shape of the side cover, resulting in poor productivity; There is a problem in that vibration-proofing and sound-proofing materials are used wastefully, increasing costs, and that the vibration-proofing and sound-proofing materials may resonate together with the retaining plate that holds them, increasing vibration noise.

Therefore, the present invention provides a side cover on the outer surface of the unit case of the power unit, and attaches a separate vibration-proofing and sound-proofing plate to a part of the inner surface of the side cover. a sound absorbing plate superimposed on the inner surface of the sound absorbing plate, having a mounting hole to the side cover at an eccentric position thereof, and further having a plurality of reinforcing ribs of different lengths formed radially on the holding plate. It is possible to achieve efficient vibration and soundproofing effects, and it also eliminates the need to use vibration and soundproofing materials more than necessary, increasing productivity.
It is an object of the present invention to provide a side cover device for a power unit for a motorcycle, which has a simple structure and prevents soundproofing material from resonating.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the entire motorcycle power unit P, in which an engine E and a transmission M are integrally formed.

The engine E is formed into a ■-shaped multi-cylinder structure having two engine blocks 1 and 2 arranged in a V-shape.

In the unit case 3 of the power unit P, that is, the crank and transmission case, a crankshaft 4 of the engine E and a main shaft 5 and a countershaft 6 of the transmission M are rotatably supported in parallel with each other. The main shaft 5 and the counter shaft 6 are interlocked with each other via a reduction gear mechanism 7 and a clutch 8, and the main shaft 5 and the counter shaft 6 are interlocked with each other via a transmission gear group 9.

A driving sprocket 10 is fixed to an end of the counter shaft 6 that projects outside the unit case 3.
0 is interlocked with a driven sprocket integrated with a rear wheel (not shown) via a chain wheel 11.

A crankshaft 4 is disposed on one side of the unit case 3.
A side cover 14 is fixed to the outer surface of the unit case 3 on the rear side of the generator 12, that is, on the mission M side, with several mounting bolts 13.

This side cover 14 faces one end of the main shaft 5 and the countershaft 6, and a mounting hole 16 for a hydraulic cylinder 15 for disconnecting the clutch 8 is bored in the part facing the main shaft 5. It is set up.

Further, on the inner surface of the side cover 14, a substantially U-shaped cheno cover 17 is provided so as to surround the drive sprocket 10.
are integrated.

Inside the chino cover 17 , a disk-shaped vibration/sound insulating plate 18 is fixed to the inner surface of the side cover 14 by a single tightening bolt 19 so as to face the outer end surface of the drive sprocket 10 .

As clearly shown in FIGS. 4 and 5, this vibration-proof and sound-proof plate 18
is made by superimposing two sound-absorbing materials made of rubber, synthetic resin, etc. on the inner surface of a holding plate 20 made of a steel plate or the like, and they are jointly fastened to the side cover 14 by the single tightening bolt 19.

The holding plate 20 has a mounting hole 2 located eccentrically from its center.
2 is bored, and a plurality of reinforcing ribs 23, 24, and 25 of different lengths are formed radially from the mounting hole 22.

These reinforcing ribs 23, 24, and 25 having different lengths change the natural frequency of each part of the holding plate 20, so that the entire holding plate 20 does not resonate when subjected to vibration. .

Further, the holding plate 20 is provided with a detent hole 26 on the outer periphery away from the mounting hole 22, and this detent hole 26 is fitted into a detent pin 27 (FIG. 2) protruding from the side cover 14. The anti-vibration and sound-insulating plate 18 is designed not to rotate even when subjected to vibration.

Next, the operation of the embodiment of the present invention will be explained.

When the engine E is operated now, the rotation of the crankshaft 4 is transmitted to the main shaft 5 via the reduction gear mechanism 7 and the clutch 8, and the rotation of the shaft 5 is further shifted as appropriate via the transmission gear group 9. After that, the signal is transmitted to the counter shaft 6, and from the shaft 6 to the rear wheels (not shown) via a chain reduction mechanism including a driving sprocket 10, a chain wheel 11, etc.

The side cover 14 that covers the outer surface of the unit case 3 can increase the mechanical impedance of the side cover itself by welding a vibration-proof and sound-proof plate 18 to its inner surface, thereby suppressing its vibration. In particular, by partially providing the vibration-proofing/sound-proofing plate 18 at the resonance generating portion of the side cover 14, an efficient vibration suppression effect can be obtained by the small-sized vibration-proofing/sound-proofing plate 18.

In addition, it is possible to effectively absorb and reduce the operating noise and vibration noise of the power transmission system, and in particular, the vibration-proof and sound-proof plate 18,
Drive sprocket 10 and chino 11 with large vibrations and noise
By facing the meshing portions of the small vibration-proof and sound-proof plates 18, an efficient noise suppression effect can be obtained.

Furthermore, the chino cover 17 has a storage space for the drive sprocket 10, and this plays the role of a resonance box, which may accentuate vibrations and noise, but this can also be effectively suppressed by the vibration-proofing and sound-proofing plate 18. .

Furthermore, the vibration-proof and sound-proof plate 18 is provided with a plurality of reinforcing ribs 23, 24, 25 of different lengths in a radial manner, thereby partially changing the natural frequency and preventing resonance as a whole. , the soundproofing effect is more effective.

As described above, according to the present invention, the side cover 14 is provided on the outer surface of the unit case 3 of the power unit P, and the vibration-proof and sound-proof plate 18 is attached to a part of the inner surface of the side cover 14, so that the side cover 14 itself The vibration of the side cover 14 is suppressed by the vibration-proofing and sound-proofing plate 18, and the operating noise and vibration noise emitted from the power transmission system of the power unit P is effectively absorbed by the vibration-proofing and sound-proofing plate 18, which is smaller than the side cover 14. Therefore, the vibration noise of the power unit P can be reduced.

Further, since the vibration-proofing and sound-proofing plate 18 is formed separately from the side cover 14 and attached to the inner surface of the side cover 14, it can be formed into any shape without being influenced by the shape of the side cover 14. It has good productivity and can be provided at a low price.

The vibration-proof and sound-proof plate 18 is composed of a holding plate 20 and a sound-absorbing plate 21 superimposed on the inner surface of the holding plate 20, and has a mounting hole 22 to the side cover 14 at an eccentric position,
Furthermore, the holding plate 20 has a plurality of ribs 23 of different lengths,
24.25 are formed radially, so the vibration-proof and sound-proof plate 18
The material itself does not resonate even when subjected to vibration, making the vibration-proofing and sound-proofing effects mentioned above even more remarkable.

[Brief Description of the Drawings] Fig. 1 is a side view of a power unit equipped with the device of the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a sectional view taken along the line m-- Fig. 2.
Fig. 4 is a front view of the anti-vibration and soundproof board, and Fig. 5 is a sectional view taken along the line -V in Fig. 4. P...Power unit, 3...Unit case, 14...Side cover, 18...
...Vibration and soundproof board.

Claims (1)

[Scope of utility model registration request] A side cover 14 is provided on the outer surface of the unit case 3 of the power unit P, and a separate vibration-proofing and sound-proofing plate 18 is attached to a part of the inner surface of the side cover 14, and the vibration-proofing and soundproofing plate 18 is
It is composed of a retaining plate 20 and a sound absorbing plate 21 superimposed on the inner surface of the retaining plate 20, and has a mounting hole 22 to the side cover 14 at an eccentric position. A side cover device for a power unit for a motorcycle, characterized in that a plurality of reinforcing ribs 23, 24, 25 of different strength are formed radially.