JPH0137570B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling water circulation system for an internal combustion engine. The present invention is applied to internal combustion engines installed in ships and other vessels that are active, and in order to suppress heating of the engine room due to the exhaust pipe as much as possible, the exhaust pipe of the internal combustion engine is cooled. The aim is to shorten the warm-up time by reducing the temperature rise of the internal combustion engine and heat lubricating oil etc. using the heat of the cooling water, which is the cooling medium, and to achieve rational operation of the internal combustion engine. be.

It is common practice to simply wrap an insulating material around the exhaust pipe to suppress the rise in temperature in the engine room.Also, it is common practice to wrap the exhaust pipe in a double shell and run cooling water between the inner and outer shells. Conventionally, efforts have also been made to reduce the temperature rise in the room. The present invention has been devised to utilize the cooling water of the double-shelled exhaust pipe as much as possible, and the present invention will be explained below with reference to the drawings.

The engine shown in FIG. 1 is an example of a V-type internal combustion engine, in which a piston 2 reciprocates around a cylinder 1 and a crankshaft 4 is rotated by a connecting rod 3. Supply air to air supply pipe 5
The combustion exhaust gas is guided into the cylinder 1 via the intake valve, and the combustion exhaust gas is guided from the exhaust valve 7 to the exhaust pipe 8 via the exhaust bellows 10 and is discharged from the exhaust outlet pipe 9.
The cylinder 1 has a cooling water chamber 11, which is formed into a double shell of the exhaust pipe 8 by a cooling water branch pipe 12.
Connects to 3. The cooling water chamber 13 is composed of an inner shell 14 and an outer shell 15, as shown in FIG. inner shell 1
4 is made of a metal material with good thermal conductivity, and preferably a fin 14' is attached to the exhaust gas side or the cooling water side to improve heat transfer efficiency. Outer shell 15 for inner shell
shall be made of a material with poor thermal conductivity, and if necessary, a heat insulating material covering 15' may be adhered to the inside and outside of the metal material, or
Take measures such as wrapping insulation around the outside. FIG. 3 is a system diagram of cooling water pipes for explaining an embodiment of the present invention, and FIG. 4 is a system diagram of cooling water pipes showing another embodiment. The internal combustion engine 20 has a cooling water chamber 11
It is connected to the cooling water pump 19 via a cooling water pipe 21, and the outlet of the cooling water chamber 11 communicates with the double shell cooling water chamber 13 of the exhaust pipe 8. 16 is the cooling water head tank, and the piping is automatic temperature control valve 1.
7, communicates with a cooling water cooler 18 and a cooling water pump 19. In FIG. 4, the circulating piping other than that shown in FIG. 3 passes through a lubricating oil tank 22 of an engine or also through a heated body 23 such as another lubricating oil purifier.

Next, to explain the operation of the present invention together with its effects, as the internal combustion engine 20 operates, the combustion exhaust gas flows into the cylinder 1.
The air is guided from there to an exhaust pipe 8 via an exhaust valve 7 and an exhaust bellows 10, and is discharged from an exhaust outlet pipe 9. Since the temperature of exhaust gas is 200 to 600℃, it is necessary to sufficiently cool the exhaust pipe to improve the livability of the engine room. Therefore, it is necessary to make the exhaust pipe a double shell and allow cooling water to flow through the inner and outer shell pipes. This makes it possible to suppress the temperature rise in the engine room. In the present invention, the inner shell 14 is made of a material with good thermal conductivity, and the fins 14' are attached on the inside or outside, so that the cooling water is further warmed by the exhaust gas, which increases the temperature of the cooling water, but the outside The shell is sufficiently insulated to have a structure with poor thermal conductivity, which prevents the temperature of the heated cooling water from dropping and prevents a rise in temperature within the engine room. The coolant that has gained heat is circulated and is partially cooled by seawater in the coolant cooler 18, and is then directly sent to the engine's coolant chamber 11 or lubricating oil tank 22 at the optimum temperature.
By introducing the cooling water into the cooling water chamber 11 of the engine via the cooling water, an appropriate cooling water temperature can be obtained. Additionally, when the engine is started, the exhaust gas warms the cooling water, so the entire cooling water system can be warmed up more quickly than before, reducing warm-up time and ensuring proper operating conditions. In addition, since a cooling water cooler 18 using seawater is provided in the circulation pipe, the automatic temperature control valve 17
Therefore, the optimum operating conditions can always be selected.

As is clear from the above description, the present invention has a double shell structure for the exhaust gas pipe of an internal combustion engine, the outer shell of the double shell has a structure with poor thermal conductivity, and the inner shell has a structure with good thermal conductivity. By forming a cooling water chamber between the shells and connecting it to the engine cooling water chamber to ensure a cooling water circulation system, the temperature rise in the engine room due to exhaust gas is suppressed, and the engine room is warmed up by the heat of the exhaust gas. It is possible to shorten operating time and allow ships to operate more quickly. Especially when it is desired to load up an engine rapidly in a cold region, it usually takes a considerable amount of time for the engine's cooling water and lubricating oil to reach a sufficiently high temperature to be able to load the engine. However, the present invention solves all of these problems at once, and has the effect of significantly limiting energy consumption compared to conventional systems that required separate fuel and electric power for warm-up.

[Brief explanation of drawings]

Fig. 1 is a schematic sectional view of the engine for explaining the present invention, Fig. 2 is an enlarged view of section A in Fig. 1, Fig. 3,
Figure 4 shows two examples of engine cooling water pipe system diagrams. 1... Cylinder, 2... Piston, 3... Connecting rod, 4... Crankshaft, 5... Air supply pipe, 6... Air supply valve, 7... Exhaust valve, 8... Exhaust pipe, 9... Exhaust outlet pipe, 10...Exhaust bellows, 11...Cooling water chamber, 12...Cooling water branch pipe, 13...Cooling water chamber, 1
4... Inner shell, 15... Outer shell, 16... Head tank, 17... Automatic temperature control valve, 18... Cooling water cooler, 19... Cooling water pump, 20... Engine, 2
1...Cooling water pipe, 22...Lubricating oil tank, 23...
... Heated object.

Claims (1)

[Claims] 1 The exhaust pipe of an internal combustion engine is formed into a double shell consisting of an outer shell and an inner shell, and the space between the inner and outer shells is used as a cooling water chamber for the exhaust pipe, and the outer shell is made of a metal material with poor thermal conductivity. and the inner shell is formed of a metal material with good thermal conductivity, and the inlet of the cooling water chamber of the exhaust pipe is communicated with the outlet of the cooling water chamber of the internal combustion engine itself, and the cooling water chamber of the exhaust pipe is connected to the outlet of the cooling water chamber of the internal combustion engine itself. An internal combustion engine characterized in that a cooling water pipe from the outlet is guided to the suction side of a cooling water pump, and the discharge side of this pump is connected to the inlet of a cooling water chamber of the internal combustion engine itself, so that cooling water is circulated. cooling water circulation system.