JPH0127915B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention improves filling efficiency by pressurizing intake air of an engine using exhaust energy of the engine.
The present invention relates to a motorcycle equipped with a turbocharged engine designed to improve its output performance.

For motorcycles equipped with a turbocharged engine, make sure that the exposed turbocharger does not interfere with obstacles, and ensure that the turbocharger's turbine, which is particularly hot, is cooled. to encourage,
etc. are required.

An object of the present invention is to provide a highly durable motorcycle equipped with a turbocharged engine that satisfies the above requirements. In order to achieve this object, the present invention provides a motorcycle in which a power unit, in which a transmission case 2 extends behind the engine, is mounted on a body frame between the front and rear wheels. A turbo supercharger, which is disposed at the rear and pressurizes the intake air of the engine, is mounted on the rear end surface of the transmission case so that its turbine is close to the outer surface of the power unit in the left-right direction of the vehicle body, in the center in the left-right direction of the vehicle body. It is characterized by being mounted more to one side.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.The body frame F of the motorcycle includes:
A power unit E is suspended between the front and rear wheels, and the engine 1 of the power unit E is in a substantially upright state, with a transmission case 2 extending rearward at the lower end of the engine body. are connected together. The transmission case 2 is constructed by integrally joining an upper case 2a and a lower case 2b that can be separated into upper and lower parts, and a turbo supercharger S is integrally mounted on the back of the lower case 2b. .

Above the turbocharger S, the front end of a rear fork 4 is pivoted 5 on the center tube 3 of the vehicle body frame F so as to be able to swing up and down. Wr is mounted on a shaft so that it can rotate freely.

Next, the configuration of the engine 1 equipped with a turbo supercharger S will be explained with reference to FIGS. 1 and 2. Four cylinders 6 are formed in the engine block, and the engine Four independent intake pipes 7, 7... are connected to the back of the block, and four independent exhaust pipes 8, 8... are connected to the front of the block, and each independent intake pipe 7 has a throttle valve 9 and a A fuel injection nozzle 10 located on the downstream side is provided. The upstream ends of the four independent intake pipes 7, 7, . and is connected to the air cleaner 13. The downstream ends of the four independent exhaust pipes 8, 8, . This exhaust collection box 14 is connected to a muffler 16 disposed on one side of the rear wheel Wr via one common exhaust pipe 15, and the common exhaust pipe 15 and the common intake pipe 12
The turbo supercharger S is provided between the two.

The turbocharger S has a turbine T installed in the middle of the common exhaust pipe 15 and a compressor C installed in the middle of the common intake pipe 12. The turbine T is formed in the middle of the common exhaust pipe 15. The compressor C is configured such that a turbine wheel 18 is housed in a turbine housing 17, and a compressor wheel 20 is housed in a compressor housing 19 formed in the middle of the common intake pipe 12. Both the housings 17 and 19 are integrally connected via a bearing holder 21, and the bearing holder 21
The two wing wheels 18,
20 are connected so that they can rotate together.

When installing the turbo supercharger S to the transmission case 2, the bearing holder 21 is attached to the back of the lower case 2b of the transmission case 2 with the turbine T and compressor C arranged in the left-right direction of the vehicle.
The turbine T is fixed to be offset from the center in the left-right direction toward the exhaust gas collection box 14 side, thereby bringing the turbine T close to the outer surface of the transmission case 2 on the exhaust gas collection box 14 side.

The upstream half 15a of the common exhaust pipe 15 from the exhaust collecting box 14 to the turbine housing 17 rises from the upper surface of the exhaust collecting box 14, and is connected to the upper outer periphery of the turbine housing 17 from diagonally above. . Further, the downstream half portion 15b of the exhaust pipe 15 extending from the turbine housing 17 to the muffler 16 protrudes from the center of the outer surface of the turbine housing 17 and is approximately parallel to the extension axis of the independent exhaust pipe 8 when viewed from the side of the vehicle. The pipe is connected to the muffler 16 so as to extend along the same line and connect to the muffler 16 from the rear end of the outermost independent exhaust pipe 8 to the front end of the muffler 16. A band-shaped decorative board 24 is disposed to cover the outer surface with a ventilation gap 23, and this decorative board 24 is fixed to a bracket (not shown) protruding from the exhaust collection box 14 and the muffler 16. . This decorative board 24 is
The front end thereof is bent outward so as to encourage the introduction of running wind into the ventilation gap 23.

When the engine 1 is in operation, its power is taken out from the output shaft 25 of the transmission and drives the rear wheels Wr via a chain transmission M as usual in the past. The collecting box 14, the turbine T, the muffler 16, and other exhaust systems are arranged on the opposite side of the rear wheel Wr.

Exhaust gas discharged from each cylinder 6 into an independent exhaust pipe 8 during the exhaust stroke of the engine 1 joins in an exhaust collection box 14, passes through a common exhaust pipe 15, and then passes through a turbine T. Give to 18. As a result, the turbine wheel 18 rotates, and the compressor wheel 2 is rotated through the rotating shaft 22.
0, the air sucked into the common intake pipe 12 from the air cleaner 13 is pressurized by the compressor C and sent to the pre-chamber 11, distributed to each of the independent intake pipes 7, and the flow rate is controlled by the throttle valve 9. After being adjusted, it is mixed with the injected fuel from the injection nozzle 10 and supplied to the cylinder 6 during the intake stroke of the engine 1. Thus, in cylinder 6,
A high air-fuel mixture filling efficiency is obtained, and the combustion of the mixture allows the engine 1 to exert high output.

When pressure pulsations are caused in each independent intake pipe 7 due to the intermittent operation of the intake valves during operation, the pressure pulsations are attenuated by the prechamber 11, and the surging phenomenon of the compressor C is prevented.

Note that 26 in the figure is an oil pan integrally formed at the bottom of the transmission case 2.

As described above, according to the present invention, in a motorcycle in which a power unit whose transmission case extends rearward than the engine is mounted on the body frame between the front and rear wheels, the power unit is disposed behind the power unit. A turbo supercharger for pressurizing intake air of the engine is mounted on the rear end surface of the transmission case so that its turbine is close to the outer surface of the power unit in the left-right direction of the vehicle body, on one side from the center in the left-right direction of the vehicle body. Since the front part of the turbo supercharger is effectively protected by the transmission case of the power unit, there is no risk of it interfering with obstacles from the front when the motorcycle is running. , damage caused by such interference can be prevented.
Moreover, by arranging the turbocharger, which tends to become particularly hot, to one side in the left-right direction on the rear end surface of the transmission case, the running wind that flows along the outer surface of the power unit is reduced. It becomes easier to apply the air to the turbine, and the air cooling effect can be enhanced. In addition, by mounting the above-mentioned turbocharger on the rear end surface of the transmission case of the power unit, the engine, which is a source of vibration, and the turbocharger become an integral structure, and the relative relationship between the two becomes Since the movement of the air can be minimized, the durability of the intake and exhaust pipes between the two can be improved even when excessive loads are placed on the connections to the turbocharger and engine. can greatly contribute to Furthermore, since the transmission case of the power unit serves both as a protection means and a support means for the turbocharger as described above, it can contribute to the simplification of the structure.

[Brief explanation of drawings]

Figure 1 is an overall side view of the motorcycle of the present invention, Figure 2 is an overall side view of the motorcycle of the present invention;
The figure is a plan view of the turbocharged engine. E...Engine, F...Vehicle frame, C...
Compressor, S...Turbocharger, T...Turbine, Wf...Front wheel, Wr...Rear wheel.

Claims (1)

[Claims] 1. The transmission case 2 connects the power unit E, which extends behind the engine 1, to the front and rear wheels Wf,
In a motorcycle mounted on a body frame F in the middle of Wr, a turbocharger S is disposed behind the power unit E and pressurizes the intake air of the engine 1, and its turbine T is connected to the power unit E. An automatic vehicle equipped with a turbocharged engine, characterized in that the transmission case 2 is mounted on the rear end surface of the transmission case 2 so as to be close to the outer surface in the left-right direction of the vehicle body, and offset to one side from the center in the left-right direction of the vehicle body. Two-wheeled vehicle.