JPH02144282A - Intake device for snowmobile - Google Patents

Abstract

PURPOSE:To enable an intake route to be selected in accordance with an operational condition by forming an intake passage, connected to an air cleaner, in a shroud and interposing a selector valve selecting the route of suction and non-suction to the air cleaner. CONSTITUTION:When a selector valve 26 closes an opening 23 by a control lever 27, an inflow of air to an engine room 7 from a through hole 9, provided in a front part shroud 6a in its front end and both upper surface sides, can be sucked to an air cleaner 14 as shown by an arrow head A. Accordingly, snow can be prevented from being directly sucked. On the contrary, when the selector valve 26 opens the opening 23, the outside air passing therethrough can be fed to the air cleaner 14 as shown by an arrow head B enabling intake efficiency to be improved. By this constitution, an optimum intake route can be selected in accordance with an operational condition.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an air intake system for a snowmobile.

[Conventional technology]

Snowmobiles are used in seasons or regions with heavy snowfall, and if they suck in snow during snowfall or when driving on fresh snow, there is a risk that the carburetor will freeze. For this reason, conventionally, as disclosed in Japanese Utility Model Publication No. 52-37376, the running wind is taken into the engine compartment from the front, and the rear part of the engine compartment is connected to the carburetor installed outside the engine compartment through a ventilation pipe. This structure prevents snow from being sucked into the engine.

[Problem to be solved by the invention]

However, in such a structure, air warmed by the engine is sucked into the engine, which reduces the amount of intake air and lowers the engine output. This tendency is particularly noticeable when the vehicle is traveling at high speed on compacted snow on a clear day. In other words, in this type of snowmobile, the entire driver is not covered by the vehicle body cover, and snow and wind directly hit the parts of the driver's body that are not covered by the vehicle body cover, so when driving on snow or fresh snow. This is because, although the vehicle can only be driven at low speeds, it is possible to travel at high speeds when driving on compacted snow on a clear day. When traveling at such high speeds, it is preferable to directly inhale outside air. The present invention was made in view of these circumstances, and provides an air intake system for a snowmobile that allows the selection of an air intake route depending on the driving situation.

[Means to solve the problem]

The intake device for a snowmobile according to the present invention includes a passage member having an intake passage extending toward an air cleaner from an opening opened to the outside of the shroud in a shroud, and a state in which outside air is sucked into the air cleaner through the intake passage. It is equipped with a switching valve that switches to a non-inhaling state.

[Effect]

In the present invention, by switching the switching valve, outside air is sucked into the air cleaner, and air inside the engine compartment is sucked into the air cleaner.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a second snowmobile equipped with the intake device of the present invention.
The sectional view taken along line I-1 in the figure and the plan view showing the front part of the snowmobile are shown in Fig. A seat 2 for a person to ride astride is supported, and footrests 3 are provided on both sides of the seat 2.
is installed. A rod-shaped steering handle 4 is rotatably supported in front of the seat 2 and connected to a pair of skis 5 arranged on both sides of the front of the vehicle body.

Further, although not shown, a crawler for driving the snowmobile is disposed below the seat 2.

The upper part of the front part of the frame 1 is covered with a shroud 6, and an engine chamber 7 is formed here. The shroud 6 includes a front shroud 6a having a downwardly sloped upper surface, and a central shroud 6b that covers the rear central portion of the front shroud 6a and whose upper surface extends in a substantially horizontal direction and supports the handle shaft 8. , and a side shroud 6C that covers the rear side of the front shroud 6a.

Through holes 9 are provided in both sides of the rear upper surface of the front shroud 6a, in a portion facing a forced air cooling device to be described later, and in the front end surface.
... is open. Further, the side shroud 6C is also provided with slit-like through holes, and these through holes provide ventilation to the engine compartment 7.

Reference numeral 11 denotes an engine housed in the engine compartment 7 and supported on the frame 1, and connected to an engine body 12 with a crankshaft supported in the vehicle width direction and having a cylinder tilted forward, and the rear side of this engine body 12. vaporizer 13,
An air cleaner 14 and the like arranged behind the carburetor 13 and above the rear part of the engine compartment 7 are provided.

15 is an exhaust pipe connected to the front of the engine body 12;
Reference numeral 6 denotes a muffler disposed on the right side of the engine body 12, the exhaust pipe 15 is once extended forward and then bent backward, and the tail pipe of the muffler 16 passes through the frame 1 downward. There is. 17 is the engine body 1
A forced air cooling device 17 is installed on the right side of the engine body 12 and is driven by the crankshaft.A forced air cooling device 17 is a centrifugal clutch installed on the left side of the engine body 12. The centrifugal clutch 18 transmits the rotation of the crankshaft to the crawler.

Reference numeral 21 represents a passage member which is an important part of the present invention. This passage member consists of an upper member 21a and a lower member 21b, and is provided at the front part of the central shroud 6b so as to sandwich this front part in the vertical direction. These upper and lower members are communicated with each other through a slit 22 in the central shroud 6b.

The upper member 21a is provided with an opening 23 that is open to the outside of the shroud toward the rear of the vehicle body, and the bottom of the lower member 21b is provided with an intake passage forming an intake passage extending toward the open end of the intake duct 14a of the air cleaner 14. A tube 24 is provided. Here, the open end of the intake pipe 24 and the open end of the intake duct 14a are opposed to each other with a gap between them.

A valve shaft 25 is rotatably supported by the upper member 21a in the vehicle width direction. The valve shaft 25 is disposed near the opening 23, and a switching valve 26 for opening and closing the opening 23 is fixed thereto. That is, this switching valve 26 opens the opening 23 to make the intake passage into a state where outside air is taken into the air cleaner 14, and by closing the opening 23, only the air in the engine compartment 7 is taken into the air cleaner 14, and outside air is not taken in. state. 27 is an operating lever connected to the right end of the valve shaft 25.

In the snowmobile intake system configured in this way, when the operation lever 27 is operated and the opening 23 is closed by the switching valve 26, the front end and both sides of the upper surface of the front shroud 6a are opened as shown by arrow A in FIG. Engine compartment 7 through a through hole 9 provided in the
The air flowing into the air cleaner 14 can be sucked into the air cleaner 14. Therefore, it is possible to prevent snow from being directly sucked in when it snows or when driving on fresh snow. In this case,
You will be inhaling air warmed by the engine 11,
Since the vehicle is not driven at such high speeds during snowfall, there is no possibility of a lack of power.

On the other hand, when the opening 23 is opened by the switching valve 26, outside air that has passed through the opening 23 can be sucked into the air cleaner 14 as shown by arrow B. Therefore, since cold outside air can be supplied to the engine 11 and intake efficiency can be increased, there is no possibility of insufficient output even when driving at high speed on a sunny day. Note that arrow C indicates the flow of air flowing into the engine compartment 7 from the through hole 9 provided at the front end of the front shroud 6a, and a portion of the air is sucked into the air cleaner 14 when the opening 23 is closed. , the flow is unaffected by the opening and closing of the opening 23.

FIG. 3 is a sectional view showing the main parts of another embodiment, and in this figure, the same or equivalent members as shown in FIG.

In this embodiment, the open end of the intake pipe 24 and the open end of the intake duct 14a are connected, and a communication port 31 is opened in the intake pipe 24 to communicate the inside of the intake passage and the inside of the engine compartment 7. There is. A switching valve 32 that opens and closes the intake passage of the intake pipe 24 at the same time as opening and closing the communication port 31 is fixedly provided on the valve shaft 33.

Therefore, in this embodiment, if the intake passage is closed by the switching valve 32, only the air in the engine compartment 7 will be sucked into the air cleaner 14 as shown by the arrow; if the intake passage is opened, then As shown by E, only outside air is drawn into the air cleaner 14.

〔Effect of the invention〕

As described above, according to the present invention, the shroud is provided with a passage member having an intake passage extending toward the air cleaner from an opening opened to the outside of the shroud, and the intake passage is configured to allow outside air to be drawn into the air cleaner. Since a switching valve is provided to switch the air cleaner to a non-inhaling state, by switching the switching valve, outside air can be sucked into the air cleaner or air inside the engine room can be sucked into the air cleaner.

Therefore, air inside the engine room can be supplied to the engine when it is snowing or driving on fresh snow, and outside air can be supplied to the engine when there is no risk of inhaling other snow. The intake route can be selected.

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken along the line I--T in FIG. 2 showing a snowmobile equipped with an intake device according to the present invention, FIG. 2 is a plan view showing the front part of the snowmobile, and FIG. 3 is another embodiment. FIG. 6...Shroud, 7...Engine compartment, 11...
...Engine, 14...Air cleaner, 21...
...Passage member, 23...Opening, 24...Intake pipe, 26°32...Switching valve. Patent applicant Yamaha Motor Co., Ltd.

Claims (1)

[Claims] In a snowmobile in which a ventilated engine compartment is covered with a shroud at the front of the vehicle body, the shroud includes:
A snowmobile provided with a passage member having an intake passage extending toward the air cleaner from an opening opened to the outside of the shroud, and a switching valve for switching the intake passage between a state in which outside air is drawn into the air cleaner and a state in which outside air is not drawn into the air cleaner. intake device.