KR20010036760A - Engine Cooling System And Method In Vehicles - Google Patents

Abstract

PURPOSE: A vehicle engine cooling device and a method thereof are provided to stop the flow of cooling water of a cylinder block and reduce an amount of circulating cooling water during a warm-up period of an engine, and cool a cylinder head prior to the cylinder block at a normal operation temperature, thereby reducing the warm-up period and improving the fuel ratio of the engine while reducing harmful exhaust gas. CONSTITUTION: In a vehicle engine cooling device, a thermostat(2) for automatically opening and closing a connection path between an engine and a radiator(4) is connected at an insertion part to a discharge part of the radiator via a tube, a bypass circuit(20) connects the other side of the thermostat with a discharge part of a cylinder head(10) and an insertion part of a water pump, the discharge part of the water pump is connected to the insertion part of the cylinder head via a tube, and a discharge part of a cylinder block(8) is connected to the insertion part of the radiator via a tube.

Description

Engine Cooling System And Method In Vehicles

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling apparatus and method for a vehicle, and more particularly, to reduce fuel consumption and harmful gas by shortening the engine warm-up period by stagnating the coolant flow on the cylinder block side during the warm-up period after engine cold start. An engine cooling apparatus and method of a vehicle are provided.

Generally, the engine cooling system of an automobile engine prevents engine overheating and maintains a normal operating temperature in all driving conditions and the entire speed range, and is a device for rapidly bringing the engine to the normal operating temperature during cold start. The pump is forced to circulate the cooling water to the engine (cylinder block and cylinder head), the radiator and the like.

1 is a conventional general engine cooling circuit diagram.

As is well known, when the engine coolant has not reached the normal operating temperature (80 to 90 ° C), such as during cold start (shown by the solid line in the figure), the thermostat 2 is closed and the thermostat 2 Only the bypass circuit is opened, and the coolant does not flow to the radiator 4 but circulates only inside the engine, and the coolant is circulated sequentially through the cylinder block 8 and the cylinder head 10 by the water pump 6. Next, the water pump 6 is circulated again via the thermostat 2. In this case, a part of the cooling water circulating in the cylinder head 10 flows through a separate cooling water hose and branches from the cooling water distributor 12, and flows into the water pump 6 through the heat exchanger of the heater 14 on one side. On the other hand, it flows to the surge tank 18 via the throttle body 16. As shown in FIG.

That is, during the warm-up period during engine cold start, the coolant is blocked from flowing to the radiator 4 and the coolant is circulated in the cylinder block 8 and the cylinder head 10 so that the engine can be quickly brought to normal operating temperature. will be.

Next, when the engine is heated to reach the normal operating temperature through the above process, the thermostat 2 is opened and the bypass circuit from the thermostat 2 to the water pump 6 is cut off. Accordingly, the coolant heated in the cylinder block 8 and the cylinder head 10 flows into the radiator 4 through the thermostat 2 and passes through the radiator 4, as shown by the thick solid line in the figure. After cooling, the water pump 6 is circulated back to the cylinder block 8 and the cylinder head 10. In this case, as in the engine warm-up period described above, some of the coolant circulating in the cylinder head 10 circulates through the heater 14 and the throttle body 16 to the water pump 6 and the surge tank 18, respectively. Circulated.

As described above, the conventional cooling apparatus closes the thermostat before reaching normal operating temperature after the engine is started, thereby preventing the coolant on the engine from flowing to the radiator and allowing the engine to circulate in the cylinder block and the cylinder head so that the engine can be rapidly returned to normal operating temperature. There is a consideration to be reached.

Shortening the warm up period of the engine is very advantageous in terms of fuel efficiency, harmful gas emission, mechanical efficiency and friction loss of the engine. Therefore, if you want to reduce the warm up period as much as possible, the cylinder block and the cylinder during the warm up period It would be most desirable to keep the coolant in the head stationary without circulating it.

In view of this, the conventional cooling device is not the best from the standpoint of shortening the warm up time since the cooling water is always circulated in the cylinder block and the cylinder head during the engine warm up period.

However, since the cylinder head portion in which the combustion chamber is formed may cause local temperature rise, if the coolant is not circulated even during the warm up period, abnormal combustion phenomenon such as knocking or premature ignition may occur. Not too much, and more is lost than the benefit of stagnating the coolant.

Looking at the cylinder block from this point of view, the coolant flow rate of the cylinder block is much higher than that of the cylinder head, so it is reasonable to think that the delay problem of the warm-up period due to the engine coolant circulation is in fact circulating the coolant of the cylinder block. Even if the coolant in the cylinder block is stagnated during the warm up period, there is almost no problem in engine performance.

The present invention has been made in view of the above, the object of the present invention is to reduce the overall coolant circulation flow rate of the engine by stopping the coolant flow of the cylinder block during the engine warm-up period, thereby reducing the warm-up period, thereby The present invention provides an engine cooling apparatus and method for improving vehicle fuel efficiency and reducing harmful gas emissions.

In order to achieve the above object, the engine cooling apparatus of a vehicle according to the present invention includes a radiator for cooling a coolant, an engine including a cylinder block and a cylinder head, a water pump for circulating the radiator, and a temperature according to the temperature of the engine. In the engine cooling apparatus of a vehicle having a thermostat for automatically opening and closing the connection passage between the engine and the radiator, one inlet side of the thermostat is connected by a conduit from the discharge side of the radiator, the other side of the thermostat A bypass circuit is provided for connecting the discharge side of the cylinder head and the inlet side of the water pump, and the inlet side of the cylinder head is connected by a conduit from the discharge side of the water pump, and the radiator of the radiator is discharged from the discharge side of the cylinder block. A sphere where the incoming side is connected by a pipeline The features.

In addition, the engine cooling method of the vehicle according to the present invention in the engine cooling method of the vehicle in which the coolant cooled in the radiator is circulated by the thermostat and the water pump to the cylinder block, the cylinder head, and the radiator, the coolant inside the engine By closing the thermostat by closing the thermostat from the discharge side of the cylinder block to the inlet side of the radiator and the thermostat before reaching the normal operating temperature of the valve, the bypass connecting the inlet side of the water pump from the discharge side of the cylinder head Opening the pass circuit, such that the coolant in the cylinder head flows from the cylinder head discharge side through the bypass circuit of the thermostat to the inlet side of the water pump and from the water pump discharge side back to the inlet side of the cylinder head. → thermos → → water pump again of the worm-up state constituting the refrigeration cycle of the cylinder head cooling water circulation step; When the coolant inside the engine reaches a predetermined normal operating temperature, the thermostat is opened to open the pipeline connected to the inlet side of the thermostat through the discharge side of the radiator, and the inlet side of the water pump is discharged from the discharge side of the cylinder head. By closing the bypass circuit connecting, the cooling water cooled in the radiator flows into the thermostat, flows from the thermostat to the inlet side of the water pump, and then flows from the discharge side of the water pump to the inlet side of the cylinder head to close the cylinder head. After cooling, the coolant having cooled the cylinder head is transferred to the cylinder block to cool the cylinder block, the radiator is introduced into the radiator through the discharge side of the cylinder block, cooled, and then flows back into the thermostat through the discharge side of the radiator. → West Thermostat water pump → → → the cylinder head cylinder block cooling water → re-cycle at the time of normal temperature to configure a cooling cycle of the radiator; Characterized in that made.

1 is a conventional general vehicle engine cooling circuit diagram

2 is a view showing an example applied to the cooling system, V-type engine according to the present invention.

Figure 3 is a cooling system showing the flow of coolant during the engine warm up period in the cooling device of the present invention

4 is a cooling system diagram showing the flow of cooling water when the engine reaches a normal temperature in the cooling apparatus of the present invention.

5 is a circuit diagram of an engine cooling apparatus according to the present invention.

<Explanation of symbols for main parts of drawing>

2: thermostat 4: radiator

6: water pump 8: cylinder block

10: cylinder head 14: heater

16: throttle body 20: bypass circuit

22: bypass circuit

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

2 is a system diagram of an engine cooling apparatus of a vehicle according to the present invention, which shows an example applied to a V-type engine. The same parts as in FIG. 1 will be described with the same reference numerals.

First, the engine cooler of the vehicle according to the present invention has a configuration in which the coolant flows from the radiator to the thermostat, unlike a conventional cooling device that allows the coolant to flow from the thermostat to the radiator. Unlike conventional chillers that send coolant from the cylinder block side to the cylinder head side, the coolant is sent from the water pump to the cylinder head side to cool the cylinder head first, then cool the cylinder block and flow back to the radiator. It has a basic concept.

In the engine cooling apparatus of the vehicle of the present invention having such a basic concept as shown in Figure 2 is connected to the discharge side of the radiator 4 to the inlet side of the thermostat (2) by the conduit, the thermostat (2) The bypass circuit 20 which connects the discharge side of the cylinder head 10 and the inlet side of the water pump 6 to the other side of is provided, and the discharge side of the water pump 6 is introduced into the cylinder head 10. The inlet side of the radiator 4 is connected by a conduit from the discharge side of the cylinder block 8 to the side. Although not shown in the drawing, the cylinder head 10 and the cylinder block 8 are naturally formed with respective water jackets, and these water jackets are in communication with each other.

In the bypass circuit 20, there are two conduits for connecting the cylinder head 10 side and the thermostat 2 because the example drawings are based on the V-type engine. Thus, one of these two conduits is a conduit extending from the left cylinder head and the other is a conduit extending from the right cylinder head.

The valve body 2a inside the thermostat 2 has a cooling water passage flowing from the radiator 4 and a bypass circuit from the cylinder head 10 according to the temperature of the cooling water flowing from the cylinder head 10 side. 20) Selectively opening and closing the cooling water passage flowing into. That is, when the temperature of the coolant is lower than the normal operating temperature, the valve body 2a moves downward in the drawing to close the radiator 4 side passage, and the bypass circuit 20 is opened. When the temperature is higher than the normal operating temperature, the valve body 2a moves upward in the drawing to block the middle of the bypass circuit 20 connecting the water pump 6 from the cylinder head 10.

In addition, a portion of the thermostat 2 in which the bypass circuit 20 is formed is connected to the inlet side of the heater 14 and the throttle body 16 while communicating with a conduit connected from the discharge side of the cylinder head 10. Another bypass circuit 22 is provided. The pipe line extending from the discharge side of the heater 14 and the throttle body 16 is connected to the middle of the pipe line of the bypass circuit 20. Here, as in the present embodiment, the cooling water from the discharge side of the throttle body 16 is introduced into the water pump 6 by joining the cooling water from the heater 14 via the surge tank 18.

Designated by reference numeral 24 is an oil cooler commonly employed in a vehicle equipped with an automatic transmission, the oil cooler 24 of which is installed in the middle of a pipe connecting the discharge side of the cylinder block 8 and the inlet side of the radiator 4. As a result, a part of the cooling water from the cylinder block 8 side passes.

Hereinafter, a cooling process of an engine cooling apparatus of a vehicle according to the present invention configured as described above will be described.

3 is a system diagram showing the flow of the coolant during the engine warm up period in the cooling apparatus of the present invention, Figure 4 is a system diagram showing the flow of cooling water when the engine reaches a normal temperature in the cooling apparatus of the present invention. FIG. 5 is a diagram illustrating the above-described engine cooling apparatus as a circuit, wherein a circulation path shown by a solid arrow in a chain box represents a cooling water circulation cycle during a warm up period and is thick outside the box in a chain line. The circulation path, shown by the solid arrows, represents the coolant circulation cycle when the normal operating temperature is reached.

First, when the engine is operated, the water pump 6 is operated at the same time to feed the cooling water, and the cooling water circulation in the apparatus to be described below is performed by the pump pressure of the water pump 6 as described above.

If the coolant temperature inside the engine reaches a predetermined normal operating temperature, that is, during the warm-up period, as shown in FIGS. 3 and 5, the thermostat 2 is closed to radiate from the discharge side of the cylinder block 8. The pipeline connected to the inlet side of the thermostat 2 via the discharge side of (4) is closed by the valve body 2a and simultaneously connects the inlet side of the water pump 6 from the discharge side of the cylinder head 10. The bypass circuit 20 is opened.

As such, as the cooling water circulation path flowing from the radiator 4 to the thermostat 2 is closed, there is no flow of cooling water in the radiator 4. Similarly, since the discharge side of the cylinder block 8 is connected to the radiator 4, according to the coolant stagnation in the radiator 4, naturally, the coolant in the cylinder block 8 does not flow anywhere. As a result, the coolant in the cylinder head 10 does not flow into the cylinder block 8 side, but flows into the thermostat 2 through the discharge side thereof, so that the water pump along the bypass circuit 20 provided in the thermostat 2. 6) flows into.

Therefore, the coolant flowing into the water pump 6 is pumped into the cylinder head 10 to cool the cylinder head 10, and then the cycle flowing into the water pump 6 through the bypass circuit 20 is performed. Will be.

In sum, the main flow of coolant during the warm-up period before the engine reaches the normal operating temperature is made up of the cylinder head 10 → the thermostat 2 → the water pump 6 → again, the cylinder head 10. The coolant in the stagnant cylinder block 8 is quickly heated by the combustion heat of the engine. In addition, the total amount of coolant circulated during the warm up period limits the amount of coolant in the cylinder block 8 from the amount of conventional coolant, that is, the cylinder head 10, the thermostat 2, and the water pump 6. Is the amount of coolant in the circulation path. Therefore, the amount of circulation of the cooling water becomes very small during the warm up period, so that the cooling water itself that is circulated also heats up more quickly. As a result, the warm-up period of the engine is shortened by the engine reaching the normal operating temperature more quickly.

On the other hand, a part of the coolant flowing into the thermostat 2 through the discharge side of the cylinder head 10 during the above-mentioned warm-up period is transferred to the heat exchanger and throttle body 16 of the heater 14 through another bypass circuit 22. After flowing into the), the water pump 6 is joined to the middle of the bypass circuit 20 connected to the inlet side. Since the coolant flows into the heater 14 and the throttle body 16 whenever the engine is running, the coolant always flows not only in the above warm-up period but also when the engine reaches a normal operating temperature.

Next, when the warm water temperature inside the engine reaches a predetermined normal operating temperature by performing the warm up as described above, as shown in FIGS. 4 and 5, the thermostat 2 is opened to operate the radiator 4. The pipeline connected to the inlet side of the thermostat 2 through the discharge side of the thermostat 2 is opened and the bypass circuit 20 connected to the water pump 6 from the cylinder head 10 discharge side is closed.

Therefore, the coolant cooled in the radiator 4 flows into the thermostat 2, flows from the thermostat 2 to the inlet side of the water pump 6, and then the cylinder head from the discharge side of the water pump 6. Inflow to the inlet side of (10) to cool the cylinder head (10).

In addition, since the conduit flowing into the thermostat 2 through the radiator 4 from the discharge side of the cylinder block 8 is opened as described above, the cooling water pressure stagnated in the cylinder block 8 is released, thereby allowing the cylinder head ( Cooling water passing through the water jacket of 10) and cooling the cylinder head 10 is transferred to the water jacket of the cylinder block (8). At this time, a part of the coolant cooling the cylinder head 10 flows to the throttle body 16 and the heater 14 through the other bypass circuit 22 of the thermostat 2 as in the warm-up process described above.

Again, the coolant having cooled the cylinder block 8 as described above flows into the radiator 4 through the discharge side of the cylinder block 8 and is cooled, and through the discharge side of the radiator 4 to the thermostat 2. Flowed into the water pump (6), and then the radiator (4) → thermostat (2) → water pump (6) → cylinder head (10) → cylinder block (8) → back to the radiator (4) Will be done.

The amount of cooling water circulation at the normal operating temperature is not different from the conventional one, but the circulation path of the cooling water is configured to cool the cylinder head 10 first, and then cool the cylinder block 8. Therefore, since the cylinder head 10 having a relatively high temperature is cooled first, the entire engine is cooled uniformly, and the intake port portion of the cylinder head 10 is well cooled, thereby improving the intake efficiency.

As described above, according to the present invention, the coolant flow of the cylinder block is stopped during the engine warm-up period, and the amount of circulated coolant is also reduced. In addition, the cylinder head is cooled before the cylinder block at the normal operating temperature.

In this way, the present invention can shorten the warm-up period after cold start, and can enjoy very advantageous advantages in the fuel economy and efficiency of the engine and the emission of harmful gases.

Claims (4)

A radiator 4 for cooling the cooling water, an engine including the cylinder block 8 and the cylinder head 10, a water pump 6 for circulating the radiator 4, and the temperature according to the temperature of the engine. In the engine cooling apparatus of a vehicle having a thermostat (2) for automatically opening and closing the connection passage between the engine and the radiator (4), One inlet side of the thermostat 2 is connected by a conduit from the discharge side of the radiator 4, and the discharge side of the cylinder head 10 and the water pump 6 are connected to the other side of the thermostat 2. The bypass circuit 20 which connects the inlet side is provided, and the inlet side of the cylinder head 10 is connected by a conduit from the discharge side of the water pump 6, and from the discharge side of the cylinder block 8, An engine cooling apparatus for a vehicle, characterized in that the inlet side of the radiator (4) is connected by a pipeline. The method according to claim 1, One side of a portion of the thermostat 2 in which the bypass circuit 20 is formed is connected to the inlet side of the heater 14 and the throttle body 16 while communicating with a conduit connected from the discharge side of the cylinder head 10. Another bypass circuit (22) is provided, wherein the discharge side of the heater (14) and the throttle body (16) are connected in the middle of the pipeline of the bypass circuit (20). In the engine cooling method of a vehicle in which the coolant cooled in the radiator (4) is circulated by the thermostat (2) and the water pump (6) to the cylinder block (8), the cylinder head (10), and the radiator (4), Before the coolant inside the engine reaches a predetermined normal operating temperature, the thermostat 2 is closed to close the pipeline connected from the discharge side of the cylinder block 8 to the inlet side of the radiator 4 and the thermostat 2. At the same time, by opening the bypass circuit 20 connecting the inlet side of the water pump 6 from the discharge side of the cylinder head 10, the coolant in the cylinder head 10 is discharged from the cylinder head 10 discharge side. The cylinder head 10, which flows into the inlet side of the water pump 6 through the bypass circuit 20 of the thermostat 2 and flows from the water pump 6 discharge side thereof back into the inlet side of the cylinder head 10. ) → thermostat (2) → water pump (6) → again, the cooling water circulation process at the time of warm up constituting the cooling cycle of the cylinder head (10); When the coolant inside the engine reaches a predetermined normal operating temperature, the thermostat (2) is opened to open the conduit connected to the inlet side of the thermostat (2) through the discharge side of the radiator (4) and at the same time the cylinder head. By closing the bypass circuit 20 which connects the inlet side of the water pump 6 from the discharge side of 10, the cooling water cooled in the radiator 4 flows into the thermostat 2, and the thermostat thereof 2) flows into the inflow side of the water pump 6, and then flows from the discharge side of the water pump 6 to the inflow side of the cylinder head 10 to cool the cylinder head 10, and to cool the cylinder head 10. After the coolant is transferred to the cylinder block 8 to cool the cylinder block 8, the coolant is introduced into the radiator 4 through the discharge side of the cylinder block 8, cooled, and then again through the discharge side of the radiator 4. book The cooling cycle of the radiator (4) → thermostat (2) → water pump (6) → cylinder head (10) → cylinder block (8) → again radiator (4) to be introduced into the thermostat (2) Cooling water circulation process at normal temperature; Engine cooling method of the vehicle, characterized in that consisting of. The method according to claim 3, At the same time as performing the coolant circulation process during the warm up, a part of the coolant flowing from the cylinder head 10 to the thermostat 2 is heated by another bypass circuit 22 provided in the thermostat 2. The bypass circuit 20 which transfers the water 14 to the throttle body 16 and cools the heater 14 and the throttle body 16 to the water pump 6 from the thermostat 2. Joining into the middle of the pipeline, Simultaneously with the cooling water circulation process at the normal temperature, a part of the cooling water transferred from the cylinder head 10 to the cylinder block 8 connects the thermostat 2 from the cylinder head 10. After entering the thermostat (2) through the (20), all of the introduced coolant is passed through the heater 14 and the throttle body (16) through another bypass circuit 22 provided in the thermostat (2) And the cooling water cooling the heater 14 and the throttle body 16 thereof are joined to the middle of the pipeline of the bypass circuit 20 connecting the water pump 6 from the thermostat 2. Engine cooling method of the vehicle, characterized in that.