JPH0314726A - Suction device for engine of snow mobile - Google Patents

Abstract

PURPOSE:To prevent the snow having flowed into a cooling duct together with the outer air from intruding to the suction passage of engine directly through the use of the inertia force by arranging the suction passage divergent from the cooling wind duct, which leads the outer air to the engine. CONSTITUTION:When a blower 45 is actuated in association with operation of an engine, the outer air 54 is sucked into the longitudinally oriented part 42 of a cooling wind duct 39 from a plurality of openings 37. Part of the sucked air 54 is sucked as the engine cooling wind 55. A part 55b of this engine cooling wind 55 is sucked to a cylinder cover 31a and a carburettor cover 35a, and upon passing through No. 1, No. 2 suction passages 47, 48 is inhaled by the cylinder. The rest of the sucked air 54 is sucked directly to the suction passages 47, 48 as a cool air 57. Eventually included snow in the sucked air 54 shall forcedly be attracted to the blower 45 side to prevent the snow from being sucked directly to the suction passages 47, 48.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an intake system for an engine of a snowmobile, and more particularly to a system that prevents snow from entering the intake air of the engine. (Prior Art) When a snowmobile moves vigorously, a lot of snow falls onto the vehicle body, regardless of whether it is snowing or not. In this case, if this snow gets mixed into the engine's intake air, it will cause the carburetor, which is the fuel supply system, to freeze, significantly hindering engine operation. For this reason, some vehicles have conventionally provided a vehicle strength bar that completely covers the components of the vehicle body such as the engine and its auxiliary equipment to protect them from snow (for example, Japanese Utility Model Publication No. 56-23131). (Problems to be Solved by the Invention) By the way, when the entire component of a heavy body is destroyed by the vehicle strength bar as described above, the shape of the vehicle strength bar becomes large.
This causes problems such as the weight of the vehicle body becoming heavier and the molding of the vehicle body strength bar becoming complicated. (Objective of the Invention) This invention was made in view of the above-mentioned circumstances, and it is possible to reduce the ilj physical strength bar without impeding the operation of the engine, thereby reducing the weight of the vehicle. Another object of the present invention is to facilitate the molding of a vehicle body strength bar.

(Structure of the Invention) A feature of the present invention for achieving the above object is that an intake passage is connected to the intake section of the engine via a combustion supply device, and cooling air extends from outside the vehicle toward the engine. In a snowmobile equipped with a duct and a blower that sends outside air to the engine side through this cooling air duct,
This is where the intake passage above is branched from the cooling air duct.
(Function) The function of the above configuration is as follows.

When the blower 45 is operated, air 54 flows into the cooling air duct 3.
9 to the engine l4 side, thereby cooling the engine l4.

On the other hand, the first and second intake passages (intake passages) 47, 48a that guide intake air to the engine l4 are branched from the cooling air duct 39, and are part of the air 54 flowing inside this cooling air duct 39. portion is taken into the engine l4 through the first and second intake passages (intake passages) 47, 48a.

By the way, the cooling air duct 3 is used for cooling the engine 14.
The amount of air 54 flowing through the air blower 45 is sufficiently large compared to the intake air amount of the engine 14.
Due to the operation of , the water is forced to flow vigorously towards the engine l4.

Therefore, when snow enters the cooling air duct 39 together with the air 54, this snow also flows forcefully toward the engine 14 together with the air 54. Therefore, as described above, the snow flowing forcefully inside the cooling air duct 39 is caused by its inertia to move through the first and second intake passages (
It is not possible to suddenly change the direction of snow in order to enter the air intake passage (47, 48a), and in other words, this snow is prevented from being mixed into the intake air of engine l4. As a result, the operation of the engine 14 is prevented from being inhibited, such as freezing of the carburetor (fuel supply device) 35 provided in the intake section of the engine 14. (Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 2, 1 is a snowmobile, and a body frame 2 of this snowmobile 1 is formed by framing a circular vibrator. A pair of left and right steering skis 3 are supported at the front portion of the vehicle body frame 2 so as to be freely steerable. Further, a steering shaft 6 is rotatably supported on the front part of the vehicle body frame 2, and the lower end of the steering shaft 6 is connected to the steering ski 3.
connected to the side. On the other hand, at the upper end of the steering shaft 6,
A bar-type handle 8 is attached, and the steering ski 3 is interlocked with the steering operation of the handle 8.

On the other hand, a Noya arm 10 is pivotally supported in the front and back midway portions of the vehicle body frame 2 so as to be vertically swingable.
A slider 1l is pivotally supported at the swinging end of the slider 11, and a pair of front and rear rotating wheels 12, 12 are supported on the slider 11.

14 is an engine, and a power transmission device 15 is connected to the rear of the engine 14, and the engine 14 and the power transmission device 15 are firmly supported by the vehicle body frame 2. The output shaft l6 of the power transmission device l5 has a driving wheel l7.
is attached, and this drive wheel l7 and the slider 11
, and the endless track belt 18 is wrapped around the rotating wheels 12.12. At the rear of the vehicle body frame 2 is a seat 22 for the rider.
is installed. Further, a vehicle strength bar 23 is provided which covers the vehicle body components such as the vehicle body frame 2 and the engine 14 from the front and both left and right sides. This car strength bar 2
Reference numeral 3 is made of resin, and includes a front force bar 24 that covers the vehicle body components from the front, a pair of left and right side force bars 25 that extend rearward from both sides of the front cover 24 and cover the vehicle body components from the measurement direction, and It is composed of a hot cover 26 that covers the vehicle body components from above.

Then, when the engine l4 is operated and this power is transmitted to the endless track belt l8 via the power transmission device 15 etc., the endless track belt l8 rotates on the snow surface 27, so that the snowmobile 1 can run. It is said that

In FIG. 1 and FIGS. 3 to 5, the engine 14 is a two-stroke engine, which has a crankshaft 29
The engine has a crankcase 30 that houses the engine, and a cylinder 3l that projects upward from the crankcase 30, and the cylinder 3l is covered with a cylinder force bar 31a. This cylinder force bar 31a is connected to a main cover 31 made of sheet metal.
a+, and resin-made left and right covers 3 1 a2. connected to each side of the main cover 31a+. 3 1 as, and an opening 3lb that opens toward the outside is formed on the rear surface of the left cover 31a*.

Further, the power transmission device l5 is connected to the crank case 30.
The power transmission case 32 has a power transmission case 32 extending rearward from the rear side, and inside the power transmission case 32 is a V-belt winding means 3 for interlockingly connecting the output shaft l6 side to the crankshaft 29.
3 is internally possessed. A carburetor 35, which is a fuel supply device, is attached to the intake portion of the cylinder 3l. This carburetor 35 is covered with a resin carburetor cover 35a, and this carburetor cover 35a is connected to the cylinder force bar 31a, and the insides of both are in communication with each other. On the other hand, the hot hoodie 26 has an inverted U shape with a flat cross section.
It is shaped like a letter, with three openings on each side.
7 is formed. Further, on the right side of each of the cylinder 31 and the carburetor 35, a cooling air duct 39 made of resin and extending in the front-rear direction is provided. This cooling air duct 39 is divided into front and rear parts,
The divided ends are connected to each other by a rubber joint duct 40. The rear part of the cooling air duct 39 is composed of a horizontal duct 4l extending in the front-rear direction and a vertical duct 42 extending upward from the rear end of the horizontal duct 4l. It's stuck inside. Further, a notch 43 is formed at the rear opening edge of the vertical duct 42. In the above case, the upper end of the vertical duct 42 is at approximately the same level 4 above and below the upper edge of each opening 37, especially as shown in FIG.
It is said to be 4. The front end of the cooling air duct 39 extends toward the cylinder 3l, and a centrifugal blower 45 is provided at the front end. This blower 45 is operated by the crankshaft 29, and the outlet of this blower 45 is connected to the cylinder force bar 3la.

An intake case 46 is integrally molded on the left end surface of the vertical duct 42. At the lower end of this vertical duct 42,
Labyrinth-shaped first intake passage 4 extending in the vehicle width direction
7 is formed, and an opening 47 at the right end of this first intake passage 47
a opens toward the inside of the vertical duct 42, and opens at a substantially right angle to the axis of the vertical duct 42.

Further, an opening 47b at the left end of the first intake passage 47 is formed in the left side wall of the intake case 46. An intake pipe 48 is provided that communicates this opening 47b with the carburetor 35, and an inner hole of this intake pipe 48 serves as a second intake passage 48a that communicates the first intake passage 47 with the carburetor 35. ．． That is, the first intake passage 47 and the second intake passage 48a are branched from the cooling air duct 39.

Further, the inside of the carburetor cover 35a is connected to the first intake passage 4.
A communication pipe 49 is provided to communicate with 7. Furthermore, an opening 50 is formed in the bottom left side of the vertical duct 42, and a communication pipe 5l is provided to communicate the opening 50 with the front part of the power transmission case 32, while the rear end of the power transmission case 32 is connected to the rear end of the power transmission case 32. An outlet port 52 is formed in the.

Then, when the engine 14 is operated and the blower 45 is operated accordingly, the external air 54 is sucked in from the upper end of the vertical duct 42 through each opening 37. In this case, as described above, the upper end of the vertical duct 42 and each opening 37
Since the upper edges are at approximately the same level 44, the air 54 trying to be sucked into the vertical duct 42 through the opening 37 once draws a downward convex arc when passing through the opening 37. It turns out. Therefore, if there is snow that tries to enter the vertical duct 42 together with the air 54, the centrifugal force will cause the snow to be shaken downward from the flow of the air 54, thereby causing the snow to mix into the intake air of the engine l4. +h is prevented.

A part of the air 54 taken into the vertical duct 42 is
The cooling air 55 of the engine l4 is sucked into the blower 45 through the cooling air duct 39, and from there the cylinder cover 31
It is blown towards a. Then, after cooling the cylinder 31, a part of the cooling air 55a cools the cylinder 31, and then the cooling air 55a cools the cylinder 31.
It is discharged to the outside through b.

On the other hand, the cooling air 55b for the other part of the cooling air 55 is blown into the carburetor cover 358 after cooling the cylinder 31. By the way, this other part cooling air 55b is after cooling the cylinder 3l and is warm, so this other part cooling air 55b warms the carburetor 35 and prevents this carburetor 35 from freezing. do. In addition, this other part cooling air 55b
After heating the carburetor 35, the communication pipe 49 and the first intake passage 4 are heated.
7 and the second intake passage 48a to reach the vaporization gain 35, where it is mixed with fuel and sucked into the cylinder 3l. Further, a part of the air 54 taken into the vertical duct 42 passes through the first intake passage 47 and the second intake passage 48a as cold intake air 57 of the engine l4, and then enters the carburetor 35.
The air is mixed with fuel and sucked into the cylinder 3l in the same manner as the other cooling air 55b.

In the above case, the weight ratio of the other part cooling air 55b and the cold intake air 57 is approximately 3:7, and since the other part cooling air 55b is warm air as described above, the intake air by both of them is at the temperature of the outside air. It is said to be at a higher temperature. This also prevents the vaporization 2335 from freezing. By the way, the air 54 flowing in the cooling air duct 39 has a sufficiently high electric current compared to the intake air amount of the engine I4, and furthermore,
This air 54 is supplied to the engine l4 by the operation of the blower 45.
It is something that flows forcefully and forcefully towards. Therefore, when snow enters the cooling air duct 39 together with the air 54, this snow and the air 54 enter the engine 141.
It will flow vigorously towards 11. Further, the first intake passage 47 opens at a substantially right angle toward the axis of the vertical duct 42. Therefore, as described above, the snow flowing vigorously inside the cooling air duct 39 cannot suddenly change direction as it attempts to enter the first intake passage 47 due to its inertial force.
It is prevented from being mixed into the intake air of the engine l4.

Further, the remainder of the air 54 that has entered the vertical duct 42 is removed from the opening 50 by a blower (not shown) in the power transmission case 32 driven by the crankshaft 29.
and is sucked into the power transmission case 32 through the communication pipe 51. Then, this winding means 33 is cooled as cooling air 58 for the winding means 33, and then discharged from the discharge port 52.

(Effects of the Invention) According to the present invention, an intake passage is connected to the intake section of the engine via the combustion supply device, and a cooling air duct extending from outside the vehicle toward the engine is provided, and outside air is passed through the cooling air duct. In a snowmobile equipped with a blower that sends air to the engine side, the intake passage is branched from the cooling air duct, resulting in the following effects.

In other words, the amount of air that flows through the cooling air duct to cool the engine is sufficiently large compared to the intake air volume of the engine, and moreover, this air is forced to flow toward the engine by the operation of the blower. be. Therefore, when snow enters the cooling air duct together with air, the snow flows vigorously toward the engine side together with the air.

Therefore, as mentioned above, the snow flowing forcefully inside the cooling air duct cannot suddenly change direction due to its inertia to try to enter the intake passage, and in other words, this snow cannot be mixed into the intake air of the engine. Prevented. As a result, the operation of the engine is prevented from being inhibited, such as freezing of the fuel supply device provided in the intake section of the engine.

Therefore, even if the body components such as the engine are not completely covered by the vehicle body force bar as in the past, the operation of the engine will not be hindered, so by making the body force bar smaller than before, This makes it possible to reduce the weight of the vehicle and make it easier to form the vehicle body strength bar. (Margin below)

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an embodiment of the present invention, in which FIG. 1 is a perspective view, FIG. 2 is a partially cutaway side view of the entire snowmobile, and FIG. 3 is an enlarged part of FIG. 2. A cross-sectional view, Figure 4 is a plan view, and Figure 5 is a V in Figure 4.
- It is a sectional view taken along the V line. 1. Snowmobile, 14. Engine, 23. Vehicle strength bar 35. Carburizer (fuel supply device), 39. Cooling air duct, 45. Blower, 47. First intake passage, 48. a
...Second intake passage, 54...Air.

Claims (1)

[Claims] 1. An intake passage is connected to the intake section of the engine via a fuel supply device, and a cooling air duct extending from outside the vehicle toward the same engine is provided, and a blower is provided to send outside air to the engine side through this cooling air duct. In a snowmobile,
An intake system for an engine of a snowmobile, in which the intake passage is branched from a cooling air duct.