JPS6350409Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circulation type cooling device for a water-cooled engine. That is, it relates to water-cooled engines that supply cooling water from a water tank (river, pond, etc.) using a water pump built into the engine or a water pump driven by the engine but provided separately.

FIG. 1 shows a conventional structure of this type. 1 is the crankcase, 2 is the cylinder head, 3 is the hopper, 4
is a hose joint, 5 is a fuel tank, 6 is a cylinder liner, 7 is a drain pipe, 8 is a water supply pipe, 9 is a water tank, 1
0, 10' indicates a water pump, and A indicates a pond, river, etc. When the water pump 10' is driven, when the engine stops, the cooling water flows out into a pond, river A, etc., and there is no cooling water in the engine unless a foot valve or a stop is provided on the water pump 10' side. When re-driving,
Since the engine is operated without cooling water, it is necessary to take measures to improve its durability. Note that inexpensive automobile centrifugal pumps cannot be used for the following reasons.

(1) It is an open impeller and has no suction capacity unless operated underwater.

(2) A lock to prevent cooling water from flowing out is required at the same time as the engine is stopped.

The purpose of this invention is to provide a circulation type cooling system for a water-cooled engine that eliminates the above-mentioned drawbacks.The main feature of this system is that the water tank is located at a lower level than the water pump attached to the crankcase and supplies water to the crankcase. a water supply pipe that extends upward from the opening of the crankcase and has its other end located at a position higher than the top surface of the crankcase; a water level pipe that connects the other end of the water supply pipe and the water pump; A water injection pipe that opens to the atmosphere, an air pipe that connects the water injection pipe and the water level pipe at the height of the upper surface of the crankcase and is provided with a restriction, and a drain pipe that opens at a position above the air pipe of the water injection pipe. That's true.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 is a front view showing an engine equipped with an embodiment of the water pump according to the present invention, and FIG. 5 is a side view thereof. Note that Figures 2 and 3 are similar to Figures 4 and 5.
Each figure shows the case where the water pump is removed from the engine shown in the figure.

In the figure, 1a is a crankcase, 2a is a cylinder head, 4a is a hose joint, 5a is a fuel tank, 6a is a cylinder liner, 8a is a water supply pipe, 1
0a is a water pump, 11 is a flywheel, 12 is a tension pulley, and 13 is a V-belt.

FIG. 6 is an explanatory diagram showing one embodiment of a circulation type cooling device according to the present invention.

In the figure, 1b is a crankcase, and 6b is a cylinder liner.

10b is a water pump attached to the crankcase 1b, and 8b is a water supply pipe, which extends upward from an opening in the water tank at a lower level than the water pump 10b, and has its other end located at a position higher than the top surface of the crankcase 1b. . A water level pipe 16 connects the other end of the water supply pipe 8b and the water pump 10b. A water injection pipe 14 extends upward from the upper part of the crankcase 1b, opens to the atmosphere, and is provided with a cap 15. 18
An air pipe communicates the water injection pipe 14 and the water level pipe 16 at the height of the upper surface of the crankcase 1b, and is provided with a restriction. Reference numeral 7b denotes a drain pipe, which opens above the air pipe 18 of the water injection pipe 14.

The operation in the case of the above configuration will be described.

Before engine operation, the cap 15 is removed and cooling water is injected until it flows out from the drain pipes 8b and 7b, and the water level is set to H ₁ + H ₃ . Then cap 15
to prevent water leakage (H ₁ = crankcase top surface position, H ₃ = water overflow prevention height).

When the engine is operated, the water pump 10b whose discharge port is connected to the crankcase 1b at an appropriate height in the _H1 range is driven by the engine, and the cooling water is distributed from the water level pipe 16 to the water pump 10b to the crankcase 1b to the water injection pipe. 14→Air pipe 18→Water level pipe 16, and part of the flow circulates from water injection pipe 14→Drain pipe 7b
It is then drained.

If a water level _H2 is provided at the top of _H1 up to the opening of the drain pipe 7b, and an appropriate restriction is provided in the air pipe 18,
While the water pump 10b is running, the air pipe 18 is always at the water level.
The pipe 8b is filled with water due to H ₂ , and the suction pressure of the water pump 10b acts on the water supply pipe 8b to draw up cooling water from the water tank, making it possible to supply cooling water with a suction head H ₄ by the capacity of the water pump 10b.

When the engine is stopped, the supply and drain pipes 8b, 7b
The cooling water from drain pipe 7 is drained to a lower water level.
A ventilation hole is formed between b←→water injection pipe 14←→air pipe 18←→water supply pipe 8b, and the water level H ₁ of the crankcase 1b is
It will not be lower than that. Therefore, cylinder 6b
The water pump 10 remains in the cooling water even when restarted.
There is sufficient cooling required for operation until the water supply from b starts (until the cooling water is sucked up again into the water supply pipe 8b).

The reason why the water pump 10b is provided so that it operates underwater by initial water injection at the _H1 water level is that an inexpensive open type centrifugal pump can be used as the cooling water pump.

In addition, the volume of the water level pipe 16 is made sufficiently larger than the volume of the water injection pipe 14 + air pipe 18, so that the water level during initial operation is
Ensure that H ₂ is secured.

Furthermore, in FIG. 6, in place of the water pump 10b attached to the engine, a separately installed water pump 10b' driven by the engine is used, and even if the water pump 10b' is connected to the engine through a pipe joint 17, The cooling water in the crankcase will not be discharged when the engine is stopped, and this can be applied to the cases shown in FIGS. 2 and 3. In this case, the water pump needs to be primed only on the pump side, but this is mainly a case where the engine is used as an irrigation water pump set, and pump priming can be considered separately. However, the initial water injection described above is required on the engine side.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a conventional circulating cooling system for a water-cooled engine, Fig. 2 is a side view showing the engine before the water pump of the cooling system according to the present invention is installed, Fig. 3 is a front view thereof, and Fig. 4 2 is a front view of the engine shown in FIG. 2 with a water pump attached thereto, FIG. 5 is a side view thereof, and FIG. 6 is an explanatory diagram showing an embodiment of the circulation type cooling device according to the present invention. 1b...Crankcase, 7b...Drain pipe, 8
b...Water supply pipe, 10b...Water pump, 14...Water injection pipe, 16...Water level pipe, 18...Air pipe.

Claims (1)

[Scope of utility model registration request] A water supply pipe that is attached to the crankcase and extends upward from an opening in a water tank that is lower than the water pump that supplies water to the crankcase, and has its other end located at a position higher than the upper surface of the crankcase, and the other end of the water supply pipe and the above A water level pipe that communicates with the water pump, a water injection pipe that extends upward from the top of the crankcase and opens to the atmosphere, and an air pipe that connects the water injection pipe and the water level pipe at the height of the top surface of the crankcase and is provided with a restriction. A circulating cooling device for a water-cooled engine, characterized in that the water injection pipe has a drain pipe that opens above the air pipe.