JPH025060Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a coolant circulation type cooling device for an internal combustion engine used in vehicles such as automobiles.

Prior Art and Its Problems A coolant circulation type cooling device for an internal combustion engine used in a vehicle such as an automobile generally includes a coolant circulation circuit including a water jacket and a radiator provided in the engine body, and a coolant circulation circuit including a water jacket and a radiator provided in the engine body. A pump is provided in the middle of the circulation circuit and driven by the shaft output of the internal combustion engine, and the engine body is cooled by using the coolant that is energized by the pump and flows through the coolant circulation circuit as a heat medium. It's summery.

The pump used in the above-mentioned cooling device is generally a constant displacement type pump, and since the pump is driven by the shaft output of the internal combustion engine, the flow rate of the coolant flowing through the water jacket, that is, the flow rate of the coolant flowing through the water jacket, is controlled. is substantially proportional to the rotational speed of the internal combustion engine, and the amount of coolant flowing through the engine relative to the rotational speed is always constant regardless of the warm-up degree of the internal combustion engine. However, the required coolant flow rate of the water jacket is
It varies depending on the warm-up degree of the internal combustion engine, and is generally relatively small during the warm-up process or when driving in cold weather.Therefore, to prevent the internal combustion engine from overheating, the required coolant flow rate of the water jacket is reduced when driving at high temperatures. If the appropriate value is set for the conditions, the amount of coolant flowing through the water jacket will be excessive during the warm-up process or when driving in cold weather, hindering warm-up performance and deteriorating fuel economy. Also, in cold weather, heating in the vehicle interior is slow to start up, resulting in poor heating effectiveness.

Purpose of the invention In view of the above-mentioned problems with conventional cooling systems, the present invention is designed to constantly cool a water jacket with an appropriate amount of coolant flowing through it, regardless of the degree of warm-up, operating conditions, or outside temperature. It is an object of the present invention to provide an improved cooling device for an internal combustion engine, which is configured so that the amount of coolant flowing through a water jacket for the same engine speed is smaller at low temperatures than at high temperatures, so that the fluid flows.

Structure of the invention According to the invention, the present invention has a coolant circulation circuit including a water jacket and a radiator provided in the engine body, and an output of an internal combustion engine provided in the middle of the coolant circulation circuit. A first pump pumps the coolant through the coolant circulation circuit in a parallel relationship with each other when the temperature of the coolant flowing through the coolant circulation circuit is above a predetermined value by driving the shafts at the same time during engine operation. pump and a second pump, and only when the temperature of the coolant flowing through the coolant circulation circuit is below the predetermined value, the discharge port of the second pump bypasses the water jacket to circulate the coolant. This is achieved by a cooling system for an internal combustion engine having a bypass device connected in the middle of the circuit.

Effects of the invention According to this configuration, both the first pump and the second pump supply coolant to the water jacket at high temperatures, but only the first pump supplies coolant to the water jacket at low temperatures. Since coolant is supplied, during the warm-up process, the amount of coolant flowing through the water jacket for the same engine speed is smaller than after the warm-up is completed, and therefore the first pump and the second pump By setting the respective pump capacities appropriately, the amount of coolant passing through the water jacket is always at an appropriate value, improving the warm-up of the internal combustion engine, and preventing overheating after warm-up is completed. Cooling of the internal combustion engine is properly performed without causing problems.

In the above cooling device, when the engine is in the warm-up process, the discharge port of the second pump is connected to the middle of the coolant circulation circuit via the bypass device, bypassing the water jacket. The second pump continues to be driven by the engine output shaft even when the engine is in a state of Contributes to warming up.

DESCRIPTION OF EMBODIMENTS The present invention will now be described in detail with reference to embodiments with reference to the accompanying drawings.

FIG. 1 shows one embodiment of a cooling device for an internal combustion engine according to the present invention. In the figure, numeral 1 indicates a water jacket provided on the engine body including a cylinder block and a cylinder head. A coolant outlet of a water jacket 1 provided at one end of the cylinder head is connected to a temperature-sensitive valve 3 by a conduit 2.
It is connected to port 3a of.

The temperature-sensitive valve 3 may be of a general thermowax type, and has two ports 3b and 3c in addition to the port 3a, and is sensitive to the temperature of the coolant passing through the temperature-sensitive valve, When the coolant temperature is below a predetermined value, for example 80°C, port 3c is closed and port 3a is connected only to port 3b, and when the coolant temperature is above the predetermined value, port 3c is opened and port 3a is connected. In addition to port 3b, it is connected to port 3c, and as the temperature of the cooling liquid increases, the opening degree of port 3b is decreased while the opening degree of port 3c is increased. For example, when the temperature of the cooling water is 88 ° C. Port 3b is fully closed and port 3c is fully open.

A port 3c of the temperature sensitive valve 3 is connected to a hot tank 6 of the radiator 5 via a conduit 4. The radiator 5 has an atsupa tank 6 and a lower tank 7.
and a radiator core 8 provided between the atsupa tank 6 and the lower tank 7.
The double pump 1 is connected by conduits 9, 10 and 11.
2, respectively.

The port 3b of the temperature-sensitive valve 3 is connected to the middle of the conduit 9 by a bypass conduit 9a, bypassing the radiator 5.

The dual pump 12 has a first pump 14 and a second pump 15 driven by a common pump shaft 13, and the first pump 14 has a suction port 1
The second pump 15 discharges the cooling water sucked in through the suction port 15a from the discharge port 15b. The dual pump 12 was originally published in 1983.
It may be a dual pump of the type proposed in No. 37311, the pump shaft 13 of which is drivingly connected to the crankshaft of the internal combustion engine by means of a transmission, not shown. It is designed to be rotationally driven by the output.

The discharge port 14b of the first pump 14 is connected to the conduit 1
6 directly connected to the coolant inlet of the water jacket 1 provided in the cylinder block. The discharge port 15b of the second pump 15 is connected by a conduit 17 to the port 18a of the temperature sensitive valve 18.

The temperature-sensitive valve 18 may be of a general thermowax type, and has two ports 18b and 18c in addition to the port 18a, and is sensitive to the temperature of the cooling liquid passing through the temperature-sensitive valve. When the temperature of the liquid is below a predetermined value, for example 80℃, port 18c
is closed to connect port 18a only to port 18b, and when the temperature of the coolant is above the predetermined value, port 18c is opened and connected to port 18c in addition to port 18b, so that the temperature of the coolant increases. Accordingly, the opening degree of port 18c is increased while decreasing the opening degree of port 18d, and when the temperature of the coolant is, for example, 88° C., the port 18b is fully closed and the port 1 is closed.
8c is set to be fully opened.

Port 18b bypasses water jacket 1 and radiator 5 by conduit 19 and connects to conduit 9.
connected in the middle. Port 1 of temperature sensitive valve 18
8c is connected by a conduit 20 to the middle of the conduit 16, that is, to the coolant inlet port of the water jacket 1.

The water jacket 1 has another coolant outlet in addition to the coolant outlet connected to the conduit 2, and the coolant outlet supplies heat for heating the vehicle interior through a conduit 21, an on-off valve 22, and a conduit 23. It is connected to the coolant inlet of the exchanger (heater core) 24. The coolant outlet of the heat exchanger 24 is connected to the middle of the conduit 9 by a conduit 25 . As a result, the heat exchanger 24
A portion of the coolant that has passed through the water jacket 1 flows through the .

Next, the operation of the cooling device according to the present invention constructed as described above will be explained.

When the temperature of the coolant passing through the temperature-sensitive valve 3, that is, the temperature of the coolant passing through the water jacket 1, is below 80°C, the port 3a of the temperature-sensing valve 3 is in contact only with the port 3b, and the temperature-sensitive valve 3 is in contact only with the port 3b. Port 18 of valve 18
a is connected only to port 18. Therefore, at this time, all of the coolant that has passed through the water jacket 1 is transferred to the conduit 2, the temperature-sensitive valve 3, and the bypass conduit 1.
3. First pump 1 via conduits 9, 10 and 11
4 and the second pump 15. first pump 1
The coolant flowing to the second pump 15 is urged by the pump action of the pump and flows through the conduit 16 to the water jacket 1, while the coolant flowing to the second pump 15 is urged by the pump action of the pump. It flows through conduit 17, temperature-sensitive valve 18 and conduit 19 to conduit 9, bypassing water jacket 1 and radiator 5. Therefore, at this time, the water jacket 1 is supplied with coolant only from the first pump 14, and the amount of coolant flowing through the water jacket 1 is determined by the discharge amount of the first pump 14.

When the temperature of the coolant that has passed through the water jacket 1 reaches 80 degrees Celsius or higher, the port 3c of the temperature-sensitive valve 3 opens, allowing some of the coolant that has flowed out of the water jacket 1 to flow through the radiator 5. Then, the radiator 5 starts dissipating and cooling the coolant. When the temperature of the coolant passing through the temperature-sensitive valve 3 reaches 88℃, the water jacket 1
All of the coolant that has flowed out now flows through the radiator 5.

Also, the temperature of the coolant passing through the temperature-sensitive valve 18 is 80°C.
When the temperature exceeds the temperature, the port 18c of the temperature-sensitive valve 18 opens, and a portion of the coolant discharged from the second pump 15 flows through the conduit 20 and the conduit 16 to the water jacket. The flow rate of the coolant supplied to the jacket 1 increases, and the flow rate of the coolant flowing through the water jacket 1 increases. When the temperature of the coolant passing through the temperature-sensitive valve 18 exceeds 80°C, the port 18b is fully closed and the port 18c is fully open, so that all of the coolant discharged by the second pump 15 is transferred to the conduit 17. , temperature-sensitive valve 18, and conduits 20 and 16 to water jacket 1. Therefore, the flow rate of the coolant flowing through the water jacket 1 at this time is the sum of the discharge volume of the first pump 14 and the discharge volume of the second pump 15,
This increases compared to during the warm-up process when the coolant temperature is low.
FIG. 2 shows the relationship between the pump rotational speed, in other words the rotational speed of the internal combustion engine, and the amount of coolant flowing through the water jacket 1. In FIG. As is clear from this graph, according to the cooling device according to the present invention, the amount of coolant flowing through the water jacket 1 is smaller during the warm-up process (at low temperatures) than after completion of warm-up (at high temperatures). That will be understood.

In the above, the present invention has been described in detail with respect to a specific embodiment, but the present invention is not limited to this, and various other embodiments are possible within the scope of the present invention. This will be clear to those skilled in the art.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing one embodiment of the cooling system for an internal combustion engine according to the present invention, and Fig. 2 shows the relationship between the pump rotation speed and the amount of coolant flowing through the water jacket in the cooling system according to the present invention. This is a graph showing. 1... Water jacket, 2... Conduit, 3...
...Temperature-sensitive valve, 4... Conduit, 5... Radiator, 6...
... Atsupa tank, 7 ... Lower tank, 8 ... Radiator core, 9 to 11 ... Conduit, 12 ... Dual pump, 13 ... Pump shaft, 14 ... First pump, 15 ... Second pump , 16, 17... Conduit, 18... Temperature-sensitive valve, 19-21... Conduit, 22
...Opening/closing valve, 23... Conduit, 24... Heat exchanger for heating the vehicle interior, 25... Conduit.

Claims (1)

[Scope of utility model registration request] The coolant circulation circuit is provided in the engine body and includes a water jacket and a radiator, and the coolant circulation circuit is provided in the middle of the coolant circulation circuit and is always driven simultaneously by the output shaft of the internal combustion engine during engine operation. a first pump and a second pump that pump the coolant through the coolant circulation circuit in parallel with each other when the temperature of the coolant flowing through the circuit is above a predetermined value; and a bypass device that connects the discharge port of the second pump to the middle of the coolant circulation circuit by bypassing the water jacket only when the temperature of the flowing coolant is below the predetermined value. Device.