JPS6218649Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cooling device for a water-cooled internal combustion engine, and its purpose is to simplify and downsize the mounting structure of a radiator device for cooling the engine.

Hereinafter, a cooling device for a water-cooled internal combustion engine according to an embodiment of the present invention will be described with reference to the accompanying drawings.

The drawings show a cooling system for a vertical water-cooled diesel engine, which is an embodiment of the present invention.

In the figure, numeral 1 is the engine body, 2 and 3 are the cylinder block and cylinder head that constitute the engine body 1, 4 is the piston, 5 is the crankshaft which is the engine shaft, and 6 is pivotally attached to one end of the crankshaft 5. 7 is a recoil starter disposed outside the centrifugal fan 6; 8 is an engine main body 1 that surrounds the outer periphery of the centrifugal fan 6;
Each shows a synthetic resin fan case attached to the side.

The centrifugal fan 6 includes blowing blades 9, 9...
It is pivotally mounted on the crankshaft 5 with... facing towards the engine body 1 side.

Further, the fan case 8 is extended upward to form a fan chamber 10 and a radiator chamber 11 above the fan chamber 10 inside.

The centrifugal fan 6 sucks air A from a gap S formed between the side surface of the engine body 1 and the fan case 8, and transfers the air A to the fan case 8.
It acts to blow air into the upper radiator chamber 11.

Furthermore, the fan case 8 is an inner case 8 attached to the cylinder block 2 side of the engine body 1.
a and an outer case 8b that covers the opening of the inner case 8a.
The cylinder block 2 is attached to the side wall of the cylinder block 2 by bolts 12 in a state where the cylinder block 2 is closely opposed to the side wall. At this time, a gap S communicating with the outside is formed between the side wall of the cylinder block 2 and the inner case 8a.
The gap S functions as an intake air passage for the centrifugal fan 6, and a substantially annular suction port 14 is formed at the periphery of the crankshaft insertion hole 13 of the inner case 8a.

In the fan case 8, a fan chamber 10
A partition wall 15 and a deflection rib 16 are formed integrally with the inner case 8a between the radiator chamber 11 and the radiator chamber 11, and an air outlet 17 is formed between the partition wall 15 and the deflection rib 16. . Reference numeral 18 designates cooling fins projecting from the crankcase 19 at the bottom of the cylinder block 2.

The bolt 12 is attached to a bolt receiving portion 20 formed on the outer peripheral edge of the suction port 14 in the inner case 8a.
and a mounting seat 21 formed on the crankcase 19 are fastened and fixed via anti-vibration rubber 22. In this way, the bolt receiving part 20 is connected to the suction port 14 with low rigidity.
If formed on the outer peripheral edge of the recoil starter 7
Even during operation, the fan case 8 does not tilt significantly and is relatively firmly fixed. Reference numeral 23 denotes a wire mesh provided at the suction port 14 to prevent foreign matter from entering.

Furthermore, a recoil starter mounting hole 24 is formed in the outer case 8b at a position corresponding to the axis of the crankshaft 5. Note that there is no need to allow cooling air to flow into the gap between the inner peripheral surface of the recoil starter mounting hole 24 and the outer peripheral surface of the rope pulley 25 of the recoil starter 7 as in the conventional case.
The gap is narrow enough that the two do not touch.

On the other hand, a radiator device 26 for cooling the engine is disposed in the radiator chamber 11 in the fan case 8 at a position close to the outlet 17 of the centrifugal fan 6 .

The radiator device 26 includes a radiator body 27
An upper tank 28 and a lower tank 29 are attached to the upper and lower parts of the tank, respectively.

This radiator device 26 is configured such that the upper tank 28 and the lower tank 29 are connected to the inner case 8a with the upper tank 28 side inclined toward the inner case 8a side.
and the outer case 8b. That is, the radiator device 26 can be attached and detached when the outer case 8b is attached to and detached from the inner case 8a. The upper tank 28 is connected to the water jacket 31 in the cylinder head 3 via the cooling water return pipe 30, while the lower tank 29 is connected to the water jacket 33 in the cylinder block 2 via the cooling water outlet pipe 32. is connected to.

Incidentally, reference numeral 34 is a vibration isolating member interposed between the fan case 8 and the radiator device 26, and also acts as a sealing member for the cooling air A. Reference numeral 35 is a cooling air outlet formed at the upper part of the outer case 8b, 36 is a radiator grill attached to the cooling air outlet 35, 37 is a water supply port, and 38 is an overflow pipe.

Next, the operation of the illustrated cooling system for a water-cooled internal combustion engine will be explained.

When the engine body 1 is operated and the centrifugal fan 6 rotates, the cooling air flows from the gap S between the side wall of the cylinder block 2 and the inner case 8a to the fan through the suction port 14 of the inner case 8a, as shown by arrow A. The air is sucked into the case 8, is further increased in pressure by the centrifugal fan 6, is blown out from the air outlet 17 while being deflected by the deflection ribs 16, passes through the radiator main body 27, and is discharged from the cooling air outlet 35 to the outside. released to. At this time, the cooling air A cools the lubricating oil in the crankcase 19 by exchanging heat with the cooling fins 18 while passing through the gap S, and cools the cooling water W while passing through the radiator body 27. It works like this.

On the other hand, as shown by arrow W, the cooling water flows from the radiator device 26 through the cooling water outlet pipe 32, the water jacket 33 of the cylinder block 2, the water jacket 31 of the cylinder head 3, and the cooling water return pipe 30 to the radiator device 26. During this period, the cylinder block 2 and cylinder head 3 are cooled. This cooling water W is caused to undergo natural convection due to the temperature difference between the engine body 1 side and the radiator device 26 side.

Next, the effects of the cooling device for a water-cooled internal combustion engine of the present invention will be listed below.

That is, according to the present invention, (1) the fan case 8 that surrounds the centrifugal fan 6 is extended upward to form a fan chamber 10 and a radiator chamber 11 therein; Since the radiator device 26 is provided, the member covering the centrifugal fan 6 and the member covering the radiator device 26 can be integrated, and costs can be reduced by reducing the number of parts. (2) The fan case 8 is divided into an inner case 8a that is fixed to the engine body 1 side and an outer case 8b that covers the opening of the inner case 8a, and a radiator device 26 is sandwiched and fixed between the inner case 8a and the outer case 8b. This eliminates the need for special bolts, etc. for mounting the radiator device 26, and the fan case 8 serves as a support member for the radiator device, making it possible to downsize the engine and facilitate attachment and detachment of the radiator. (3) The cooling water natural convection circulation path between the upper tank 28 and the lower tank 29 of the radiator device 26 and the cooling air path from the centrifugal fan 6 are each configured with the shortest path, and at the intersection of the two. Since the radiator main body 27 is located in the structure, the flow resistance in both passages is minimized, and it is possible to improve the cooling efficiency of the radiator device 26 and promote the engine cooling efficiency, contributing to engine downsizing. It has practical effects such as:

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view of a main part of a water-cooled internal combustion engine equipped with a cooling device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view in FIG. It is a diagram. 1... Engine body, 2... Cylinder block, 3
... Cylinder head, 5 ... Engine shaft, 6 ... Centrifugal fan, 8 ... Fan case, 8a ... Inner case, 8b ... Outer case, 10 ... Fan chamber, 1
1...Radiator room, 26...Radiator device,
27...Radiator body, 28...Upper tank,
29... lower tank, 31, 33... water jacket.

Claims (1)

[Scope of utility model registration request] A fan case 8 that surrounds a centrifugal fan 6 pivotally mounted on one end of the engine shaft 5 is extended upward to form a fan chamber 10 and a radiator chamber 11 inside, and the fan case 8 is placed on the side of the engine body 1. The radiator chamber 11 has an upper tank 2 which communicates with a water jacket 31 in the cylinder head 3.
8, a lower tank 29 communicating with the water jacket 33 in the cylinder block 2, and both tanks 2
A radiator device 26 for cooling the engine is provided with a radiator main body 27 that connects the radiator parts 8 and 29, such that the upper tank 28 and the lower tank 29 are sandwiched and fixed between the inner case 8a and the outer case 8b. A cooling device for a water-cooled internal combustion engine, characterized in that the cooling device is detachably installed.