JPS61146633A - Engine cooler for riding vehicle - Google Patents

Abstract

PURPOSE:To prevent overheat by covering the outercircumference of the cylinder and cylinder head of air-cooled engine with air-shroud while enabling forced air-cooling of cylinder through rotation of fan arranged in the shroud. CONSTITUTION:An engine 11 for riding vehicle mounting balloon tires suitable for travelling over coarse land is provided with a cylinder 12 upstanding from the crank case 18 where many fins 12a, 13a are projected from said cylinder 12 and cylinder head 13. Here, the cylinder 12 and the cylinder head 13 are covered with an air-shroud 14. The air-shroud 14 is constructed with a shroud body 15 and first and second shroud covers 16, 17 where a fan 23 to be rotated by the engine 11 through a belt 30 is arranged at the inside. Through rotation of said fan 23, the outer air is sucked through suction side opening 16a and discharged through exhaust side opening 17a.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a riding type vehicle such as a tricycle or a four-wheeled motor vehicle equipped with balloon tires on the front and rear wheels, and particularly to a cooling device for the engine thereof.

[Prior art]

This type of vehicle has the stability of two rear wheels and low-pressure wide balloon tires, allowing it to run easily on uneven terrain or wetlands.Recently, it has been used not only for races and leisure purposes, but also for agricultural purposes, for example. It is also used for practical purposes such as towing heavy and large agricultural machinery.

(Problem to be Solved by the Invention) Conventionally, this type of vehicle is equipped with an air-cooled engine similar to a motorcycle, and this air-cooled engine is located between the front wheels and the bottom of the seat. It is installed in

However, when used for agricultural purposes as described above, in addition to the high load operation despite the low running speed, the balloon tires in front of the engine prevent the flow of cooling air to the engine. Since the engine is easily blocked, the amount of cooling air tends to be insufficient while driving, and if high-load operation continues for a long time, there is a risk that the engine will overheat.

Furthermore, since the running speed is low, the hot air from the engine rises while the vehicle is in operation, exposing the driver to the hot air, resulting in increased discomfort.

[Means for solving problems]

Therefore, in the present invention, the outer periphery of the cylinder and cylinder head of an air-cooled engine is covered with an air shroud,
This air shroud is connected to an outside air inlet and an outlet, and a fan is installed to forcibly blow the outside air sucked in from this inlet toward the cylinder and cylinder head, and the air shroud is connected to the outside air inlet and outlet. It is characterized by forced air cooling.

[Effect]

With this configuration, the area around the cylinders is forcibly cooled by the outside air that the engine itself draws in by rotating the fan, so even when operating at low speed and under load, it is possible to obtain sufficient cooling air. This can prevent overheating.

Furthermore, since the cooling air after cooling the engine is discharged outward from the exhaust port, the driver is not exposed to the heat of the engine when idling or driving at low speeds, which alleviates discomfort.

[Embodiments of the invention]

A first embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

In the figure, reference numeral 1 denotes a frame, and a pair of left and right front wheels 4.4, which are steered via a bar handle 2 and a steering shaft 3, are supported at the front of the frame 1. front wheel 4
．． 4 is covered from above to the rear by front fenders 5.5 made of synthetic resin, and these front fenders 5.5 are integrated on the left and right sides and are fixed to the frame 1. A pair of left and right rear wheels 6.6 are supported at the rear of the frame 1, and a seat 7 on which a driver A sits astride is installed above between these rear wheels 6.6. A fuel tank 8 is installed between the seat 7 and the front bar handle 2, and the outer periphery of the fuel tank 8 is covered with a cover 9 having an open bottom.

Note that the air pressure of the front wheels 4.4 and rear wheels 6.6 is 0.
．． It is equipped with wide balloon tires 10 with low pressure of 1 to 0.2 Kg/cIi.

By the way, the frame 1 has a front wheel 4.4 and a rear wheel 6.6.
A four-stroke, single-cylinder, air-cooled engine 11 is mounted between the seat 7 and below the front end of the seat 7. This engine 11 includes an upright cylinder 12 on a crankcase 18, and a large number of cooling fins 12a and 13a are protruded from the cylinder 12 and cylinder head 13, and the outer periphery of the cylinder 12 is shown in FIG. As shown, it is covered by an air shroud 14. The air shroud 14 is a shroud body 1 that continuously covers the front, upper and rear surfaces of the cylinder 12 and cylinder head 13.
5, and a first cover that covers the left opening of the shroud body 15.
The second shroud cover 11 covers the right side opening of the shroud body 15, and is bolted to the crankcase 18 and crankcase cover 19. An opening 16 formed at the upper end of the first shroud cover 16
a is connected to an intake passage 21 on the left front fender 5 via an intake duct 20 extending forward, and an intake port 22 of this intake passage 21 opens forward at a position higher than the front wheel 4. ing.

A fan 23 is disposed within the air shroud 14 and is located on the left side of the cylinder 12 and cylinder head 13 to suck in outside air. A rotating shaft 24 of the fan 23 is supported by a support portion 25 extending from the upper surface of the crankcase cover 19 via a bearing 26, and a secondary sheave 27 is fixed to one end of the rotating shaft 24. Also,
One end of the crankshaft 28 housed in the crankcase 18 passes through the crankcase cover 19, and a V-belt 30 is wound between the primary sheave 29 fixed to this penetrating end and the secondary sheave 21. There is. Therefore, the fan 23 is rotated together with the crankshaft 28, and this rotation forces the outside air sucked in from the intake port 22 into the space 31 between the air shroud 14, the cylinder 12, and the cylinder head 13. It looks like this.

An opening 17a opening at the upper front surface of the second shroud cover 11 is connected to an exhaust passage 33 on the right front fender 5 via an exhaust duct 32 extending forward. The outlet 34 opens toward the side of the vehicle body. In the case of this embodiment, the shroud main body 15 also integrally covers the exhaust pipe 35 led out from the front surface of the cylinder head 13. It is guided to the right, that is, routed rearward through the second shroud cover 17 on the opposite side from the fan 23, and connected to a muffler 36 installed between the rear wheels 6.6.

Therefore, this exhaust pipe 35 is also forcedly air cooled together with the cylinder 12 and cylinder head 13. Further, the air shroud 14 has a substantially sealed structure from the outside, and measures are taken to prevent muddy water from entering the air shroud 14 even when the vehicle is traveling in a wetland or the like.

In the figure, reference numeral 37 indicates left and right footrests, and 38 indicates an integrated left and right rear wheel ender that covers the front and upper portions of the rear wheels 6.6.

According to the first embodiment of the present invention, the crankshaft 2
When the fan 23 is rotated in conjunction with 8, the outside air taken in from the suction port 22 is forcibly blown into the air shroud 14. Then, this outside air flows through the air shroud 14.
The cylinder 12, cylinder head 13, and exhaust pipe 5 are forcibly cooled while flowing through the inner space 31, and the outside air whose temperature has been raised by this cooling passes through the exhaust duct 32 and the exhaust passage 33 to the exhaust port 34. is discharged outward from the

Therefore, even when operating at low speed and under high load, a sufficient amount of cooling air is guided around the cylinders, which are heat generating parts of the engine 11, and overheating can be prevented.

In addition, the hot air from the engine 11 is discharged to the side of the front fender 5 by the outside air flowing in the air shroud 14, so the hot air does not rise as it is. is not exposed to heat. In addition, since the cylinder 12 and cylinder head 13 are covered with the air shroud 14, the noise of the engine 11 can be insulated to some extent, and discomfort during operation is alleviated compared to the conventional system.

In the first embodiment described above, the outside air intake port 22 is provided on the front fender 5, but the present invention is not limited to this. For example, the second embodiment of the present invention shown in FIGS. 6 and 7 As in the example, the upper end of the first shroud cover 16 may be extended toward the upper fuel tank 8 side, and the intake port 41 that opens below the fuel tank 8 may be provided at the extended end.

In this case, it is desirable that the suction port 41 be located inside the cover 9 and located above the lower edge of the cover 9 to make it difficult to suck in dust and the like.

Roughly speaking, as in the third embodiment of the present invention shown in FIG. The suction port 51 may be opened close to the seat bottom plate 7a of the seat 7.

Further, the opening position of the exhaust port and the installation position of the fan are not limited to those in the above embodiments, and the engine is not limited to a four-cycle engine, but may be a two-cycle engine.

Further, the riding type vehicle according to the present invention is not limited to a four-wheeled motor vehicle, and can be similarly applied to a three-wheeled motor vehicle having one front wheel, for example.

〔Effect of the invention〕

According to the present invention described in detail above, even when operating at low speed and under high load, a sufficient amount of cooling air is forced around the cylinders, which are the heat generating parts of the engine, so overheating can be prevented. It can be prevented. In addition, since the hot air from the engine is carried away by the outside air flowing inside the air shroud, the hot air does not rise up as it is, and as a result, the driver is not exposed to hot air when idling or driving at low speeds, compared to conventional methods. This has the advantage of significantly reducing discomfort while driving.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention.
The figure is a sectional view of the engine area, Figure 2 is a side view of the four-wheeled motor vehicle, Figure 3 is a plan view of the four-wheeled motor vehicle, Figure 4 is a front view of the four-wheeled motor vehicle, and Figure 5 is the third In the figure ■Arrow view seen from the line direction,
6 and 7 show a second embodiment of the present invention, and FIG.
7 is a sectional view of the engine and its surroundings, and FIG. 8 is a partially sectional side view showing a third embodiment of the present invention. 4...Front wheel, 6...Rear wheel, 1...Seat, 10.
...Balloon tires, 11...Air-cooled engines, 12.
...Cylinder, 13...Cylinder head, 14...
Air shroud, 22.41°51...Inlet, 23
...Fan, 34...Exhaust port.

Claims (1)

[Claims] Equipped with low-pressure wide balloon tires on the front and rear wheels,
In a riding type vehicle in which an air-cooled engine is mounted between the front wheels and the rear wheels and below the seat that the driver straddles, an air shroud covers the outer periphery of the cylinder and cylinder head of the air-cooled engine. An engine cooling system for a riding type vehicle, characterized in that an intake port and an exhaust port for outside air are communicated with each other, and a fan is provided for forcibly blowing outside air taken in from the intake port toward the cylinder and cylinder head. Device.