JPH0216330A - Motorcycle provided with engine having turbocharger - Google Patents

Abstract

PURPOSE:To facilitate incorporation of a turbocharger by coupling an exhaust pipe extending downward to an exhaust port which is opened on the front surface of a cylinder head on a cylinder head which is inclined forward, and arranging a mechanical turbocharger in a space between the exhaust pipe and a crank case. CONSTITUTION:A cylinder block 9 inclined forward is erected on the upper surface of a crank case 7, and the cylinder head 13 above the upper part of the cylinder block 9 is projected forward from the front surface 7a of the crank case 7. A carbureter 18 is coupled to an intake port 14 which is formed on the rear surface of the cylinder head 13, meanwhile an exhaust pipe 20 extending downward is coupled to an exhaust port 17 which is formed on the front surface of the cylinder head 13. Further, a space 21 is formed between the exhaust pipe 20 and the front surface 7a of the crank case 7. In addition, a mechanical turbocharger 24 which is interposed on the middle of an intake pipe passage 23 is arranged in the space 21, so that the rotor 26 of the turbocharger 24 is rotated interlockingly through gear lines 28 to 30 by a crank shaft 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a motorcycle equipped with a mechanical supercharger driven by the shaft output of an engine.

[Conventional technology]

Mechanical supercharger driven by engine shaft power,
The so-called supercharger provides good throttle response without the operational delay that occurs with turbochargers, so recent attempts have been made to install supercharged engines in motorcycles. .

[Problem to be solved by the invention]

By the way, since this supercharger is generally driven by the shaft output of the crankshaft, it is desirable to install it as close to the engine as possible in consideration of power transmission from the crankshaft.

However, especially in motorcycles equipped with multi-cylinder engines, intake system parts such as the engine, carburetor, and air cleaner are arranged in a limited space within the frame. Recently, air cleaners have become larger in order to reduce intake noise, so the space around the engine tends to become smaller.

For this reason, it becomes difficult to secure a space for installing the supercharger around the engine, which creates problems in the layout of the supercharger and complicates the path for extracting the driving force.

Therefore, the present invention provides an engine with a supercharger that allows the supercharger to be placed comfortably by utilizing the dead space between the crankcase and the exhaust pipe, and also allows easy extraction of driving force. Providing motorcycles equipped with 1]
target

[Means to solve the problem]

Therefore, in the present invention, the cylinder block of the engine is tilted forward with respect to the vertical line, and the cylinder head stacked on this cylinder block is made to protrude forward beyond the front end of the crankcase. It is characterized in that an exhaust pipe that extends downward is connected to the open exhaust port, and a mechanical supercharger that is driven by the shaft output of the engine is provided in the space between the exhaust pipe and the crankcase.

[Operation] According to this configuration, as the cylinder block is tilted forward, the exhaust pipe extending downward from the exhaust port of the cylinder head passes through a position farther forward than the front surface of the crankcase. A relatively wide space can be secured between the exhaust pipe and the crankcase, and the supercharger can be easily placed just in front of the crankcase. Therefore, the dead space in front of the crankcase can be effectively used as installation space for the supercharger, and the supercharger can be installed compactly without significantly changing the basic layout around the engine.

Also, since the supercharger is located just in front of the crankcase,
The driving force can be easily taken out, and the drive system of the supercharger can be downsized and simplified.

〔Example〕

The present invention will be explained below based on an embodiment shown in the drawings.

Reference numeral l in FIG. 1 is a frame that constitutes the body of a motorcycle, and a steering head vibe 3 at the front end of the frame has a
A pair of left and right main vibes 4 extending rearward and a pair of left and right down tubes 5 extending downward are welded. An engine 6 is supported between the main vibe 4 and the down tube 5. The engine 6 of this embodiment is a 4-stroke, water-cooled, 4-cylinder engine, and includes a crankcase 7 that is divided into upper and lower halves. A crank holder 8 extending along the width direction of the vehicle body is supported within the crankcase 7, and a cylinder block 9 is erected on the upper front surface of the crankcase 7. There are four cylinders 1 in the cylinder block 9.
0 are arranged in parallel in the width direction of the car body, and each of these cylinders 10
A piston 11 and a crankshaft 8 are connected via a connecting rod 12.

As shown in FIG. 2, the cylinder block 9 is tilted significantly forward in the direction of travel with respect to the vertical line The cylinder head 13 is
It protrudes more forward than the front surface 7a of the crankcase 7. The cylinder head 13 is formed with an intake port 15 that is opened and closed by an intake valve 14 and an exhaust port 17 that is opened and closed by an exhaust valve 16. The intake port 15 is opened upward at the rear surface of the cylinder head 13, and a downdraft type carburetor 18 is installed at the open end of the intake port 15.
are connected, and these vaporizers 18 are connected to a surge tank 19 above.

In addition, a 1 air hole 1 opened at the front of the cylinder head 13 is provided.
7 is connected to an exhaust pipe 20 that extends downward.

After passing through the front of the crankcase 7, the exhaust pipe 20 passes below the crankcase 7 and extends rearward, and between the exhaust pipe 20 and the front surface 7a of the crankcase 7,
A space 21 is formed.

Note that the reference numeral 36 in the figure indicates a radiator that cools engine cooling water.

Incidentally, an air cleaner 22 is integrally connected to the front surface of the surge tank 19. This air cleaner 2
2 is located directly above the cylinder head 3, and is connected to the surge tank 19 via the intake pipe 23.
This intake pipe 23 is equipped with a mechanical supercharger 2 that pumps the intake air purified by the air cleaner 22 to the surge tank 19.
4 is provided. This supercharger 24 is housed in a space 21 between the crankcase 7 and the exhaust pipe 20, and in the case of this embodiment, a casing 25 constituting the outer shell of the supercharger 24 is located at the front of the crankcase 7. It is bolted to 7a. Two screw-shaped rotors 2G are accommodated within this casing 25. Rotor 2B
is provided parallel to the crankshaft 8, and is rotatably supported by the casing 25 in a state where four parts (not shown) formed on the outer circumferential surface and a convex part are engaged with each other.

As shown in FIG. 3, the rotating shaft 27 of one rotor 2G is inserted into a bulge 7b protruding from the front surface 7a of the crankcase 7, and a driven gear is pivotally supported within this bulge 71). It is coaxially connected to the shaft portion 28a of 28.

The driven gear 28 is connected to the crankshaft 8 via an intermediate gear 29.
It meshes with the upper reducing gear 30, and this driven gear 28
The number of teeth is smaller than the number of teeth of the reducing float 30.

Therefore, the rotor 26 of the supercharger 24 is rotationally driven by the shaft output of the crankshaft 8, and the rotational speed of the crankshaft 80 is increased and transmitted.

Further, an inlet 31 is opened in the lower surface of the casing 25 and is located at one end of the rotor 26 in the axial direction. It is connected to the air cleaner 22 above.

A discharge port 33 for delivering pressurized intake air is opened on the second surface of the casing 25 at a position deviated from the suction port 31 in the axial direction of the rotor 26 . Discharge port 3
3 is connected to the upper surge tank 1 via the downstream intake pipe 34.
9, and a water-cooled intercooler 35 that cools the pressurized intake air is provided in the middle of this downstream intake pipe 34. This intercooler 35 has a rectangular box shape, and in this embodiment is placed astride the upper surfaces of the surge tank 19 and the air cleaner 22. The intercooler 35 is connected via a cooling water pipe 37 to a sub-runner 38 that is separate from the engine cooling radiator 3G, so that the intake air cooling system and the engine cooling system are separate and independent systems. ing.

Note that this sub-radiator 3B is arranged immediately in front of the cylinder head 13.

In the middle of the cooling water pipe 37, a water pump 40 is provided which is located on the downstream side of the sub-radiator 38 and circulates the cooling water. The water pump 40 is attached to the left side of the cylinder head 13, and a fuel tank 43 is also arranged behind the surge tank 19.
The surroundings of the fuel tank 43, surge tank 19, air cleaner 22, and intercooler 35 are covered by a cover 44 that forms a conventional tank shape.

In such a case, the shaft output of the crankshaft 8 is transmitted to the rotor 2B via the intermediate gear 29 and the reduction gear 30.
, the two rotors 26 mesh with each other and rotate in opposite directions, sucking the intake air purified by the air cleaner 22 from the intake port 31, pressurizing this intake air, and passing it from the discharge port 33 to the downstream intake pipe 34. Send it inside. This pressurized intake air is guided to the intercooler 35, and is cooled by heat exchange with cooling water while passing therethrough. This cooled intake air is introduced into the surge tank 19 and then distributed to the carburetor 18 of each cylinder 10, thereby starting supercharging.

By the way, in the above configuration, as the cylinder block 9 of the engine G is tilted forward, the cylinder head 1
The exhaust pipe 20 extending downward from the exhaust port 17 of No. 3 passes through a position farther forward than the front surface 7a of the crankcase 7. Therefore, a wide space 2[ can be secured between the exhaust pipe 20 and the front surface 7a of the crankcase 7, and the supercharger 24 can be easily arranged within this space 21.

Therefore, the dead space created in front of the crankcase 7 can be effectively utilized as an installation space for the supercharger 24, and the supercharger 24 can be installed without significantly changing the basic layout around the engine. Can be incorporated compactly.

Moreover, in the case of the above configuration, since the supercharger 24 is located just in front of the crankcase 7, the rotating shaft 27 of the rotor 26 and the crankshaft 8 are close to each other, and power can be easily extracted from the crankshaft 8. I can do it.

Therefore, there is an advantage that the drive system of the supercharger 24 can be downsized and simplified.

In the above embodiment, the casing of the supercharger is bolted to the crankcase, but depending on the case, the crankcase and the casing may be integrally molded.

Further, the driving means of the supercharger is not limited to gears, and may be driven by a belt. For example, in an engine provided with a balancer shaft in front of the crankshaft, it may be driven by the shaft output of this balancer shaft.

Further, the rotor of this supercharger is not limited to a screw shape, and may be a roots-type supercharger combining cocoon-shaped rotors, for example.

〔Effect of the invention〕

According to the present invention detailed above, a supercharger can be installed by effectively utilizing the dead space between the front of the crankcase and the exhaust pipe, and the basic layout around the engine can be significantly changed. The supercharger can be incorporated compactly.

Furthermore, since the supercharger is located just in front of the crankcase, the shaft output of the engine can be easily taken out, and the drive system for the supercharger can be simplified and downsized.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a side view of a motorcycle, Fig. 2 is a side view of a supercharged engine, and Fig. 3 is a partially sectional view of the drive system of the supercharger. FIG. 6...Engine, 7...Crankcase, 9...
Cylinder block, 13... Cylinder head, 17...
...Exhaust port, 20...Exhaust pipe, 21...Space, 24
...Supercharger.

Claims (1)

[Claims] The cylinder block of the engine is tilted forward with respect to the vertical line, and the cylinder head stacked on the cylinder block protrudes forward beyond the front end of the crankcase, and the exhaust port that opens at the front of the cylinder head faces downward. An automatic engine equipped with a supercharged engine, characterized in that extending exhaust pipes are connected and a mechanical supercharger driven by the shaft output of the engine is provided in the space between the exhaust pipe and the crankcase. Two-wheeled vehicle.