JPS6193264A - Intake-air device in motor-cycle - Google Patents

Abstract

PURPOSE:To aim at enhancing the output characteristic of an engine, by making the opening end of an intake-air pipe confront a coupling box disposed in a V-shape space defined between engine cylinders so that the V-shape space between the engine cylinders is used for the accommodation of an intake-air device so that the latter may be positioned near to the engine. CONSTITUTION:When an engine 9 is started, the outside air is introduced into a coupling pipe 21 and a coupling box 20 through an air-purifier 22, and is then introduced into the engine 9 from the coupling box 20 through an intake-air pipe 12 which is disposed in a V-shape space. Since the intake-air pipe 12 is arranged in the upper section of the V-shape space and is connected at an opening 20a with the coupling box 20 communicated with the air-purifier 22, the V-shape space is effectively used for the accommodation of an intake-air device.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an intake device for a motorcycle.

[Prior Art] In conventional conventional motorcycles, an intake pipe extends to the rear of the engine, and an air purifier or the like is disposed below the seat.

[Problem that the invention seeks to solve]

However, in this structure, the piping of the intake system becomes long, so there is a problem that intake resistance increases. In particular, when a Type 2 engine is installed, this tendency is not only remarkable, but also the piping of the intake system becomes complicated. Therefore, the emergence of an intake device that can reduce intake resistance and simplify piping has been awaited.

[Means for solving problems]

The present invention was made in view of the above circumstances, and it is an object of the present invention to provide an intake device for a motorcycle that can reduce intake resistance and simplify piping. The intake system for a motorcycle according to the present invention connects the open end of the intake pipe provided in the ■-shaped space formed between the cylinders to the opening that is disposed above the ■-shaped space and communicates with the air purifier. It is shown inside the connecting box.

[Effect]

In the present invention, the V-shaped space of the engine is used to accommodate the intake device, thereby bringing the intake device closer to the engine.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view, partially in section, of a motorcycle in which an air intake system according to the present invention is implemented, and FIG. 2 is a side view, partially in section, of a main part of the air intake system. In these figures, the reference numeral 1 indicates a main frame, and this main frame 1 includes a steering head pipe 2. It includes a pair of left and right tank rails 3 and a pair of left and right side tubes 4. Reference numeral 5 denotes a front fork, which is rotatably held by the head pipe 2.

6 is the front wheel. Reference numeral 7 denotes a rear wheel, which is held by a rear arm 8 that is pivotally supported by the main frame 1 so as to be able to swing vertically. Reference numeral 9 denotes a ■-type engine equipped with a plurality of cylinders, each of which has cylinders 10 and 11 mounted on the side tubes 4 so as to be inclined in different directions, that is, in the front and rear directions of the vehicle body.
placed in between. The engine 9 is mounted on the side tube 4 so that it is suspended from the left and right sides.

The intake pipe 12 of the engine 9 is located on the inner surface of the cylinders 10 and 11, and extends upward substantially vertically. That is, the intake pipe 12 is provided in a square space formed between the cylinders 10 and 11. Exhaust pipes 13.
14 are connected.

The exhaust pipe 13 passes from the front of the engine 9 to below the engine 9, and is connected to an exhaust silencing box 15 disposed below the engine 9. The exhaust pipe 14 passes from the rear of the engine 9 between the pivot shaft 16 of the rear arm and the rear wheel 7, and is connected to the muffling box 15. A muffler pipe 17 is connected to the muffler box 15 for discharging exhaust gas to the rear. A radiator 18 cools the cooling water of the engine 9, and is fixed to the side tube 4.

Reference numeral 19 denotes a fuel tank installed astride the tank rail 3. The upper part of the intake pipe 12 enters the inside of the fuel tank 19. The upper open end 12a of each intake pipe 12 opens toward the inside of the connection box 20, as shown in FIG. The connection box 20 is located above the V-shaped space, inside the fuel tank 19, and sandwiched between the pair of tank rails 3, and has an air purifier (described later) on the bottom. An opening 20a for communication is provided.

21 is a connecting pipe extending downward from the opening 20a of the connecting box 20. This connecting pipe 21 is arranged approximately parallel to the intake pipes 12 at a position surrounded by each intake pipe 12, and an air purifier 22 is provided at the lower end thereof.

Note that the intake pipe 12 is provided with a known carburetor, and the output of the engine 9 is changed by controlling the throttle valve 23. Further, 24 is a sheet.

In the intake system for a motorcycle configured in this way, when the engine 9 is started, outside air enters the connecting pipe 21 and the connecting box 20 from the air cleaner 22. Intake air is drawn into the engine 9 from the connection box 20 through the intake pipe 12.

Here, the intake pipe 12 is provided in the V-shaped space, and the intake pipe 12 is connected to the connection box 20 arranged above the V-shaped space and communicated with the air purifier 22 through the opening 20a. The V-shaped space between the cylinders 10 and 11 can be effectively used to accommodate the intake device, and the intake device can be moved relatively closer to the engine 9 than in the past. Therefore, the piping of the intake system can be shortened.

In the embodiment, the volume of the connecting box 20 is made sufficiently large so that the intake pulsation of each cylinder can be absorbed, so that the connecting box 20 can have a function as an intake silencer, and the intake noise can be significantly reduced. can be reduced.

〔Effect of the invention〕

As explained above, according to the present invention, the opening end of the intake pipe provided in the ■-shaped space formed between the cylinders is connected to the opening that is disposed above the ■-shaped space and communicates with the air purifier. Since it faces into the connection box with the engine, the square-shaped space of the engine can be used to accommodate the intake device, and the intake device can be brought closer to the engine.

Therefore, since the piping of the intake system can be shortened, not only the intake resistance is reduced and the output performance of the engine is improved, but also the piping can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a side view, partially in section, of a motorcycle in which an air intake system according to the present invention is implemented, and FIG. 2 is a side view, partially in section, of a main part of the air intake system. 9...Engine, 12...Intake pipe, 12a...
...Top opening end, 19...Fuel tank, 20...
・Connection box, 22...Air purifier.

Claims (1)

[Claims] In a V-type engine equipped with a plurality of cylinders that are inclined in different directions, an intake pipe having a throttle valve is provided in a V-shaped space formed between the cylinders, and the open end of this intake pipe is connected to the V-shaped space. An air intake device for a motorcycle, which is arranged above a space and faces into a connection box having an opening communicating with an air purifier.