JPH0232454B2 - NAINENKIKANNOREIKYAKUSOCHI - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a cooling device for an internal combustion engine.

[Prior Art] and [Problems to be Solved by the Invention] It has been known in the past that knocking can be improved by lowering the temperature of the end gas of a compressed air-fuel mixture. However, when the cylinder head and cylinder block are cooled to a low temperature, there are problems in that the quenching of the cylinder liner increases, and the exhaust port in the cylinder head is cooled, resulting in a decrease in exhaust temperature. This decrease in exhaust temperature is due to
Decrease HC reactor action and increase HC emissions. Furthermore, in this case, not only the cylinder head but also the cylinder block become relatively low temperature, resulting in problems such as increased friction loss due to a drop in oil temperature and poor engine startability in cold weather.

Therefore, a cooling system has been proposed in which a cooling system for the cylinder head and a cooling system for the cylinder block are provided separately to cool the entire cylinder head with a particularly high cooling capacity. However, this cooling system requires a large amount of cooling water to cool the cylinder head, resulting in an increase in the size of the radiator and an increase in the weight of the vehicle. Here, the cooling system refers to a cooling system that includes a cooling flow path formed in the cylinder head (or cylinder block) and a heat exchanger such as a radiator that is communicated with this through a pipe or the like. shall be.

This invention was devised to solve these conventional problems, and provides a cooling system for an internal combustion engine that can effectively lower the temperature of end gas without causing problems such as increasing the size of the radiator. With the goal.

[Means to solve the problem]

In this invention, a first cooling passage is formed by communicating a cooling passage formed in the cylinder block with a cooling passage formed in a portion other than the vicinity of the skid area on the intake port side of the cylinder head; a second cooling flow path formed near the squish area on the intake port side of the cylinder head; cooling water is supplied to the first cooling flow path from the cylinder block side; At least the cooling water from the heat exchanger was directly supplied to the flow path.

[Effect]

In this invention, separate from the cooling system from the cylinder block to the cylinder head, the squish area included in the cylinder head is strongly cooled to prevent knocking. This effectively lowered the temperature of the end gas. Because the squish area is located on the intake side, it is lower in temperature than the exhaust side, and the flame propagation speed is lower. This is because flame propagation to the squish area is delayed, compression progresses, and self-ignition is likely to occur.

According to this invention, the cooling water flowing through the first cooling channel cools the cylinder block and cylinder head to an appropriate temperature to prevent problems such as a decrease in the HC reactor action, and the cooling water flows through the second cooling channel. Cooling water directly supplied from the heat exchanger strongly cools the squish area to prevent knocking. Note that since it is only necessary to strongly cool the squish area, less cooling water is required compared to the case where the entire cylinder head is strongly cooled.

〔Example〕

Next, a first embodiment of the cooling device according to the present invention will be described based on the drawings.

As shown in FIGS. 1 and 2, the cooling system runs from a radiator 1 through a water conduit 2 and a thermostatic valve 3 to a first cooling channel in a cylinder block 5 and a cylinder head 6 by means of a pump 4. 7
Only the second cooling channel 10 in the cylinder head 6 is introduced from the radiator 8 into the general first cooling system (white arrow in FIG. 1) and returns to the radiator 1 by the pump 9. , and a second cooling system (black arrow in FIG. 1) that returns to the radiator 8 through a water conduit 11. The thermostat valve 3 is
The system detects the coolant temperature and prevents the coolant from being introduced into the radiator 1 when the temperature is low. When the coolant is stopped from being introduced into the radiator 1, the coolant that has flowed out of the engine is returned to the engine via the bypass pipe 12. It is refluxed.

As shown in FIG. 2, this embodiment relates to a cross-flow engine, and the second cooling channel 1
0 is the squish area 13 on the intake port 14 side
Since the cooling water passes near the radiator 8 and cools only the squeezing area 13, problems such as increased quenching and oil temperature drop do not occur, and since the area to be cooled is narrow, only a small amount of cooling water is sufficient. becomes smaller and lighter. Therefore, the problem of increase in vehicle weight does not arise. Furthermore, since the second cooling flow path 10 cools the squish area 13 that is relatively far from the spark plug 16, the end gas is mainly cooled, and the knocking improvement effect in the future is high.

The second embodiment shown in FIG. 3 is an application of the cooling device shown in FIG. ing.
As a result, the end gas is reliably cooled and an extremely high knocking improvement effect can be obtained.

In the third embodiment shown in FIG. 4, a single radiator 1 is installed in the first cooling system (white arrow in FIG. 4) and the second cooling system (indicated by the white arrow in FIG. The cooling system is applied to the cooling system (black arrow) and supplies the surplus water of the first cooling system to the second cooling system, and has the advantage that only one radiator is required. Experimental results have shown that the knocking limit can be sufficiently improved even in this configuration.

〔Effect of the invention〕

As described above, the internal combustion engine cooling device according to the present invention includes, in addition to the general first cooling passage that cools the cylinder block and the cylinder head, a second cooling passage that mainly cools the skid area. Since the air-fuel mixture in the squish area is strongly cooled, it has the excellent effect of preventing knocking without causing problems such as increasing the size of the radiator.

[Brief explanation of drawings]

FIG. 1 is a piping diagram showing a first embodiment of a cooling device for an internal combustion engine according to the present invention, FIG. 2 is a longitudinal sectional view showing a cooling flow path in the same embodiment, and FIG. 3 is a cooling diagram in a second embodiment. FIG. 4 is a longitudinal sectional view showing the flow path, and FIG. 4 is a piping diagram showing the third embodiment. Note that the same or corresponding parts in the figures are indicated by the same reference numerals. DESCRIPTION OF SYMBOLS 1...Radiator, 2...Water conduit, 3...Thermostat valve, 4...Pump, 5...Cylinder block, 6...Cylinder head, 7...First cooling passage, 8...Radiator, 9 ...Pump, 10...
...Second cooling flow path, 11...Water conduit, 12...Bypass pipe, 13...Squeeze area, 14...Intake port, 15...Exhaust port, 16...Spark plug.

Claims (1)

[Claims] 1 A cooling channel formed in the cylinder block,
A first cooling passage that communicates with a cooling passage formed in a portion other than the vicinity of the squish area on the intake port side of the cylinder head, and a first cooling passage formed near the squish area on the intake port side of the cylinder head. 2 cooling channels, the first cooling channel is configured to feed cooling water from the cylinder block side, and the second cooling channel is configured to directly feed cooling water from the heat exchanger. A cooling system for an internal combustion engine configured to provide a cooling system for an internal combustion engine.