JPS62258878A - Engine cooling device for car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a vehicle with two front wheels, which is equipped with a water-cooled two-stroke multi-cylinder engine near the center of the vehicle body and has a straddle-type driver's seat in the upper part of the vehicle body. This invention relates to an engine cooling bag applied to.

(Background of the Invention) There is a vehicle for traveling on rough terrain that has a pair of left and right front wheels, has an engine mounted near the center of the vehicle body, and has a straddle-type driving seat disposed in the upper part of the vehicle body. When the engine of this type of vehicle is a two-stroke engine, an exhaust expansion pipe is usually arranged in front of the engine. Especially when this engine is a water-cooled two-cylinder engine, two exhaust expansion pipes occupy the front part of the engine. In addition, it is desirable to place the radiator for engine cooling at the front of the vehicle body, where it is easily exposed to the wind while driving.
As a result, two exhaust expansion pipes and a radiator are located in front of the engine, making it difficult for air to flow into the engine. If the cooling performance of the engine due to the running wind deteriorates, a problem arises in that the capacity of the radiator must be increased.

(Objective of the Invention) The present invention has been made in view of the above circumstances, and it is possible to make the engine easily exposed to running wind even though two exhaust expansion pipes and a radiator are disposed in front of the engine.
An object of the present invention is to provide an engine cooling system for a vehicle that can improve the cooling performance of the engine by running wind and reduce the capacity of a radiator.

(Structure of the Invention) According to the present invention, the purpose is to provide a pair of left and right steering front wheels, a water-cooled two-stroke multi-cylinder engine mounted near the center of the vehicle body, and a steering handle located in front of the engine at the upper end. In a vehicle equipped with a steering shaft to which a bar is fixed and a straddle-type driver's seat located at the upper part of the vehicle body, a pair of left and right exhaust expansion pipes disposed between the engine and the steering shaft; and a radiator disposed near the adaxial axis, and an engine cooling air passage is formed below the radiator to guide running air to the engine through between the two exhaust expansion pipes. This is achieved by the engine cooling system.

(Example) Fig. 1 is a side view of a four-wheeled vehicle for traveling on rough terrain which is an embodiment of the present invention, Fig. 2 is a plan view of its main parts, and Fig. 3 is a partially cross-sectional view of an exhaust expansion pipe. FIG.

In these figures, numeral 10 is a vehicle body frame.

A pair of left and right lower tubes 12.12, a pair of left and right upper tubes 14.14 that are connected to the front and rear ends of the lower tube 12 and bent to convex upward, and extend rearward from the upper rear part of the upper tube 14. Pair of left and right seat rails 16.16
, a cross tube 20.22.2 that connects the pack tube 18 (only one shown) and the rain tube 12.12.
4, a cross tube 26.28.30.32 connecting the circular upper tube 14.14, and an upper and lower cross tube 22.
28, and a pair of left and right front tubes 36 (only one shown) that connect the cross tube 26 and the lower tube 12.

Reference numeral 38 designates a pair of left and right front shock absorbers (only one is shown), the upper end of which is supported by the upper tube 14, and the lower end of which holds the lower arm 40 so as to be freely movable in the L direction. A pair of left and right front wheels 42 (only one is shown) is steerably attached to the lower end of each shock absorber 38, forming a strut type front wheel independent suspension system.

44 is a steering shaft, and 46 is a steering handlebar.

48 is a rear arm, the front end of which is connected to the vehicle body frame 10.
A rear wheel 52 (only one of which is shown) is fixed to the left and right ends of a rear wheel shaft 50, which is rotatably held at the rear end of the rear wheel shaft 50. A downward return force is applied to this rear arm 48 by a rear shock absorber 58 via links 54 and 56. These front wheels 42 and rear wheels 52
is equipped with wide, ultra-low-pressure tires (so-called balloon tires).

60 is a water-cooled 2-cycle 2 mounted near the center of the car body.
It is a cylinder engine. This engine 60 includes two cylinders arranged in parallel in the width direction of the vehicle body, and the cylinder 6 including each cylinder
2 stands diagonally downward and forward from the crankcase 64. There are two carburetors 66 and 68 on the rear surface of this cylinder 62.
are arranged in parallel in the width direction of the vehicle body.

68.68 is a pair of left and right exhaust expansion pipes. engine 6
The exhaust port of each cylinder of No. 0 is located on the front surface of the cylinder, and opens from between the left and right down tubes 34, pointing obliquely downward and forward. The expansion pipes 68, 68 are connected to these exhaust ports, extend diagonally downward and forward from between the left and right down tubes 34, rise upward between the engine 60 and the steering shaft 44, and extend in a vertical plane in the longitudinal direction of the vehicle body. Make one rotation so that it is almost parallel. Each expansion pipe 68 is connected to an approximately average diameter exhaust pipe 70.70 passing outside the upper part of the engine 60, and each exhaust pipe 70.70 extends rearwardly between upper tubes 14.14. The downstream side of this exhaust pipe 70.70 is connected to a muffler 72.72.

In FIG. 1.2, 74.74 is a spark plug attached to the upper surface of the cylinder 62, and in FIG. 1, 76 is a radiator disposed in front of the steering shaft 44.
0 cooling liquid. Coolant is sent to the upper part of the radiator 76 from near the upper center of the cylinder 62 by a hose 78, and the coolant cooled from the γ section of the radiator 76 is guided to the right side of the engine 60 by a hose 80. These hoses 78, 80 are connected to both expansion tubes 6
8.68 was passed. For this reason hose 78.80
is less likely to be injured by road obstacles. An engine cooling air passage A (FIG. 2) is formed below the radiator 76, passing between the expansion pipes 68, 68 and opening toward the front of the cylinder 62.

Reference numeral 82 denotes a straddle-type driver's seat that is long in the front-rear direction, and extends from the upper part of the vehicle body, that is, from above the seat rail 16 to the upper tube 1.
It is located above the rear of 4. A pair of left and right footrests 84, 84 are fixed to the lower tube 12, 12 so as to be located below the engine 60. Further, 86 is a front fender that covers the front wheel 42, 88 is a rear fender that covers the rear wheel 52, and 90 is a tank cover that covers a fuel tank (not shown).

The driver sits on the driver's seat 82 with both feet placed on footrests 84 and 84, as shown in FIG.

The exhaust expansion pipe 68 is located in front of the engine 60, and the exhaust pipe 70 of approximately equal diameter is located on the upper side of the engine 60. This makes it difficult for the feet of the operator to come into contact with the inflation tube 68.

Since an engine cooling air passage A that opens forward from the cylinder 62 is formed between both expansion pipes 68, the running air hits the cylinder 62 and the vicinity of the connection between the cylinder 62 and the expansion pipe 68, cooling them. Improves sex.

The engine of this embodiment has two cylinders arranged in parallel in the width direction of the vehicle body, but the present invention is applicable to a V53 or 4-cylinder engine in which a front bank of two cylinders and a rear bank of one or two cylinders form a V shape. It also includes engines.

(Effects of the Invention) As described above, the present invention provides a pair of left and right exhaust expansion pipes between the engine and the steering shaft, and a re-exhaust expansion pipe below the radiator located near the steering shaft. An engine cooling air passage is formed through which the running air is guided to the engine through the space 1. Therefore, the engine can be cooled by the wind while the vehicle is running, and the cooling performance of the engine is improved. Therefore, the capacity of the radiator can be reduced, and the weight of the vehicle can also be reduced by making the radiator smaller.

[Brief explanation of drawings]

FIG. 1 is a side view of a four-wheel vehicle for traveling on rough terrain, which is an embodiment of the present invention, and FIG. 2 is a plan view of the main parts thereof. FIG. 3 is a partially sectional side view of the exhaust expansion pipe. 42... Steering front wheel, 46... Steering handlebar, 60... Engine, 68... Exhaust expansion pipe, 76... Radiator, 82... Driving seat, A... Engine cooling wind passage.

Claims (1)

[Scope of Claims] A pair of left and right steering front wheels, a water-cooled two-stroke multi-cylinder engine mounted near the center of the vehicle body, and a steering shaft located in front of the engine and having a steering handlebar fixed to its upper end. and a straddle-type driving seat located at the top of the vehicle body, a pair of left and right exhaust expansion pipes disposed between the engine and the steering shaft, and a pair of left and right exhaust expansion pipes disposed near the steering shaft. 1. A vehicle engine cooling system, comprising: a radiator, and an engine cooling air passage is formed below the radiator to guide running air to the engine through between the two exhaust expansion pipes.