JPS62107222A - Engine cooling device - Google Patents

Abstract

PURPOSE:To enable the heating part of an engine to be air-cooled and water- cooled by connecting an engine air-cooling centrifugal fan to a crankshaft, and arranging a ring-shaped radiator around the outer circumference of this centrifugal fan so as to be interposed in the water cooling circuit of the engine. CONSTITUTION:When an engine E is operated, a centrifugal fan 17 and a water pump 35 are driven to be turned by a crankshaft 6. And by the rotation of the centrifugal fan 17, the outside air is taken into the inside of all upper and lower cover bodies 20, 21 through filters, passes through a radiator R, and after swirling the draft air passage 23 on the outer circumference thereof, is introduced to the outer circumference of a cylinder part 3 having cooling fins 26. Further, by the drive of the water pump 25 the cooling water inside the radiator R is forcibly discharged to the lower part of the water jacket 40 of the cylinder part 3 through conduit tubes 38 and 39, and then from the upper part thereof, is returned to the inside of the radiator R through conduit tubes 43. Accordingly, the heating part of the engine E, mainly the cylinder part 3, can be enabled to be air-cooled and water-cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION A. OBJECTS OF THE INVENTION (11) Field of Industrial Application The present invention relates to an engine cooling system capable of air cooling using a centrifugal fan and water cooling using a water cooling circuit.

(2) Conventional technology Conventionally, engines for motorcycles, etc. have been equipped with an engine air cooling system that uses a centrifugal fan linked to the crankshaft to forcefully blow cooling air to the heating section, as well as a water pump and a radiator. Water cooling systems in which cooling water is circulated through a water jacket of an engine by means of a water cooling circuit are known, and air and water cooling systems that combine these two systems are also known.

(3) Problems to be solved by the invention By the way, if the engine is equipped with both an air and water cooling system, the cooling efficiency of the engine can be increased and this can contribute to improving its performance. There is a problem in that the entire engine not only becomes larger and heavier, but also increases cost.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an air/water cooling device for an engine that is extremely compact, lightweight, and inexpensive.

B1 Structure of the Invention (]) Means for Solving the Problems To achieve the above object, according to the present invention, a centrifugal fan for air cooling of the engine is connected to the crankshaft, and a water cooling circuit for the engine is connected to the outer periphery of the centrifugal fan. An annular radiator is installed inside.

(2) Effects According to the above configuration, the heating section of the engine is air-cooled by the centrifugal fan and water-cooled by the water-cooling circuit.

(3) Examples An embodiment of the present invention will be described below with reference to the drawings.

In this embodiment, the present invention is applied to a two-stroke engine for a scooter-type motorcycle, and in FIG. is supported by the body of the motorcycle and connected to the drive shaft 2 thereof. The engine body l of the two-stroke engine E has a conventionally known structure.
As shown in FIG. 2, the cylinder portion 3 includes a piston 5.
A crankshaft 6 is rotatably supported on the crankcase portion 4, its crank pin is connected to the piston 5 via a connecting rod 7, and a spark plug 8 is mounted on the piston 5. A combustion chamber 9 is formed. An intake boat 10 having a reed valve I2 and a scavenging boat 11 are formed on the left and right sides of the engine body 1.

As shown in Fig. 2, one end of the crankshaft 6 (#A on the left in Fig. 2)
) is connected to a drive pulley 13 of a belt-type continuously variable transmission T that transmits the rotation of the crankshaft 6 to the drive shaft 2, and the other end (the right end in FIG. 2) also serves as a flywheel. An outer 14 of the alternator A is connected, and several bolts 16 are attached to the crankcase portion 4 in the outer 14.
The stator 15 of the AC power generator JIAA supported by
will be placed. An air cooling centrifugal fan 17 is fixed to the outer end surface of the outer 14 with several bolts 18.

The upper part and one side of the engine body 1 are covered by an integral upper cover 20 and an integral side cover 21, and the integral side cover 20 is fixed to the outer surface of the crankcase portion 4 by bolts 19, and the A suction port 22 facing the suction side of the fan 17 is opened, and an annular ventilation passage 23 covering the outer periphery of the centrifugal fan 17 is formed.

A filter 24 is installed over the suction port 22, and the air passage 23 communicates with an air cooling chamber 25 surrounding the outer circumferential portion of the cylinder portion 3 having cooling fins 26. When the centrifugal fan 17 is rotated by the rotation of the crankshaft 6, outside air is sucked into the side cover unit 21 through the suction port 22 as shown by the arrow ta) in FIG. The air flows into the air cooling chamber 25 surrounding the air.

An annular radiator R is disposed around the outer periphery of the centrifugal fan 17. As shown in FIG. 5, this radiator R has two cooling cores 29, 29 with a flat cross section arranged approximately in parallel between the annular inner and outer radiator plates 27, 28, and the inner and outer radiator plates 27, 28 are arranged substantially parallel to each other. 28 and the cooling core 29. The fins 30 are interposed in a staggered manner between the cooling core 29 and the cooling core 29. An inflow pipe 31 is provided at the top thereof, and an outflow pipe 32 is provided at the bottom thereof to protrude outward.

The radiator R is fixed to the outer surface of the crankcase portion 4 with several bolts 44 via an annular packing material 45, and the inflow and outflow pipes 31 and 32 pass through the side cover 21 and extend outward. It stands out.

As shown in FIG.
The suction port 36 of the water pump 35 is connected to the outlet pipe 32 of the radiator R via a flexible conduit 38, and the discharge port 37 thereof
is communicated via a flexible conduit 39 to a jacket 41 opened at the bottom of a water jacket 40 formed in the cylinder portion 3. Further, a jacket outlet 42 opened at the upper part of the water jacket 40 is communicated with the inflow pipe 31 of the radiator R via a flexible conduit 43.

When the water pump 35 is driven by the rotation of the crankshaft 6, the cooling water in the radiator R is sucked into the water pump 35 through the conduit 38 as shown by the arrow fbl in FIG. The cooling water is discharged from the third discharge port 37.
The water flows into the water jacket 40 through the conduit 39 as shown by the arrow (C) in the figure. After cooling the cylinder portion 3, the cooling water in the water jacket 40 flows back into the radiator R through the conduit 43 as shown by the arrow (d+) in FIG.

Next, the operation of this embodiment will be explained.

When the engine E is operated now, the centrifugal fan 17 and the water pump 35 are rotationally driven by the crankshaft 6. As the centrifugal fan 17 rotates, outside air passes through the filter 24 and is sucked into the upper and lower covers 20 and 21, is pressurized by the centrifugal fan I7, passes through the radiator R, and circulates through the ventilation passage 23 on its outer periphery. After that, remove the side cover 21
is guided by the cylinder part 3 of the engine E, and flows upward.
The air is guided to the outer periphery having cooling fins 26, and the cylinder portion 3 can be air-cooled mainly. Thus, when the cooling air passes through the radiator R, the radiator R can be cooled.

Also, the drive 1 of the water pump 35. By the IJ, the cooling water in the radiator R is sucked into the water pump 35 through the conduit 38, pressurized, and then forced to be sent to the lower part of the water jacket 40 of the cylinder portion 3 through the conduit 39. The cooling water that has flowed into the water jacket 40 cools the cylinder portion 3 while flowing upward within the water jacket 40, and is returned into the radiator R through the conduit 43 from above.

Therefore, the heating section of the engine E, mainly the cylinder section 3, can be air-cooled and water-cooled at the same time.

C1 Effects of the Invention As is clear from the above embodiments, according to the present invention, the heating section of the engine can be air-cooled and water-cooled at the same time, increasing its cooling efficiency and contributing to its performance.

In particular, the radiator is formed into an annular shape and is placed around the outer periphery of the air cooling centrifugal fan, so even though the radiator is relatively tall, the width of the engine in the crankshaft direction does not increase, making the whole engine compact. It can be summarized as follows.

Furthermore, the entire area of the radiator can be uniformly cooled by using an air-cooling centrifugal fan, and the cooling efficiency of the radiator can be increased.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a partial side view of a scooter-type motorcycle equipped with a two-cycle engine equipped with the device of the present invention, and FIG. Figure 3 is a longitudinal sectional view taken along the line III--III in Figure 2, Figure 4 is an exploded perspective view of the device of the present invention, and Figure 5 is a partial perspective view of the radiator. be. E...engine, R...radiator, 6...crankshaft, 17...centrifugal fan, patent applicant
Honda Motor Co., Ltd. A

Claims (1)

[Claims] An engine cooling device comprising: a centrifugal fan for air cooling the engine connected to the crankshaft; and an annular radiator disposed around the outer periphery of the centrifugal fan, which is interposed in the water cooling circuit of the engine.