JP2009287455A - Cooling device of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling device of an internal combustion engine for enhancing response by quickly bringing a temperature of cooling water closer to a target water temperature when the target water temperature of a feedback control means is changed. <P>SOLUTION: In the cooling device of the internal combustion engine for conducting the feedback control of an opening of a flow rate control valve for controlling the flow rate of the cooling water flowing in a radiator passage for circulating the cooling water to the internal combustion engine via the radiator and a bypassing passage for bypassing the radiator so that the temperature of the cooling water becomes closer to the target water temperature, when feedback control is conducted to bring the temperature of the cooling water to a first target water temperature (100°C), the cooling water which is colder than the first target water temperature is stored in a low-temperature cooling water storing part and, when the target water temperature of the feedback control is changed to a second target water temperature (80°C) which is lower than the first target water temperature, thecooling water stored in the low-temperature cooling water storing part is supplied to the internal combustion engine (S104). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cooling apparatus for an internal combustion engine, and more specifically to an apparatus for cooling an internal combustion engine by circulating cooling water through a radiator.

As an example of a cooling device for an internal combustion engine, the technique described in Patent Document 1 below can be cited. In Patent Document 1, the target temperature of the cooling water is determined according to the operating state of the internal combustion engine, that is, the load and the rotational speed, and the opening degree of the thermostat valve is feedback controlled so that the detected temperature becomes the target temperature. The technology is described.
Japanese Examined Patent Publication No. 2-59289

  In the technique described in Patent Document 1, when the target temperature of the cooling water is changed according to the operating state, the detected temperature is set to the target temperature by controlling the flow rate of the cooling water on the radiator passage side and the bypass passage side by the thermostat valve. Therefore, when the temperature of the cooling water in the radiator is high, it is difficult to quickly reduce the temperature of the cooling water in the engine even if the thermostat valve is operated quickly. Further, when the temperature of the cooling water in the engine is raised, the temperature of the cooling water is raised only by the heat generated by the engine, so that it is difficult to raise the temperature quickly.

  Accordingly, an object of the present invention is to eliminate the above-mentioned problem, and when the target water temperature of the feedback control means is changed, the internal combustion engine which quickly brings the temperature of the cooling water close to the target water temperature to increase the responsiveness. It is in providing a cooling device.

  In order to achieve the above object, according to claim 1, a radiator passage for circulating cooling water to an internal combustion engine via a radiator, a bypass passage for bypassing the radiator, the radiator passage and the bypass passage are provided. In a cooling device for an internal combustion engine, comprising: a flow rate control valve that controls a flow rate of flowing cooling water; and a feedback control unit that feedback-controls the opening degree of the flow rate control valve so that the temperature of the cooling water approaches a target water temperature When the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature, a low temperature for storing cooling water having a temperature lower than the first target water temperature in the low-temperature cooling water storage unit The target water temperature of the cooling water storage means and the feedback control means is changed to a second target water temperature lower than the first target water temperature. When in was as configured, characterized in that the cooling water stored in the cold coolant reservoir and a cold cooling water supply means for supplying to the internal combustion engine.

  In the cooling apparatus for an internal combustion engine according to claim 2, the low-temperature cooling water storage section is configured to include the radiator.

  In Claim 3, the radiator passage which circulates cooling water to an internal-combustion engine via a radiator, the bypass passage which bypasses the radiator, the flow volume which controls the flow volume of the cooling water which flows through the radiator passage and the bypass passage An internal combustion engine cooling apparatus comprising: a control valve; and a feedback control unit that feedback-controls an opening degree of the flow rate control valve so that the temperature of the cooling water approaches a target water temperature. The feedback control unit includes the cooling water. When feedback control is performed so that the temperature approaches the first target water temperature, the high-temperature cooling water storage unit that stores cooling water having a temperature higher than the first target water temperature in the high-temperature cooling water storage unit, and the feedback control When the target water temperature of the means is changed to the second target water temperature higher than the first target water temperature, the high-temperature cooling water storage The pooled coolant was composed as and a high-temperature cooling water supply means for supplying to the internal combustion engine.

  In the cooling device for an internal combustion engine according to a fourth aspect, the high temperature cooling water reservoir is configured to include a heating means for heating the cooling water.

  In the cooling device for an internal combustion engine according to claim 5, a downstream radiator passage provided downstream of a portion connected to the bypass passage downstream of the radiator, and the high-temperature cooling water storage in the downstream radiator passage. A high temperature cooling water passage provided with a portion, a second bypass passage provided in parallel with the high temperature cooling water passage, and a second flow rate for controlling a flow rate of the cooling water flowing through the high temperature cooling water passage and the second bypass passage. And when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature, the flow of the cooling water to the high-temperature cooling water passage is shut off, When the feedback control means performs feedback control so that the temperature of the cooling water approaches the second target water temperature, the high-temperature cooling water Was composed as and a second flow rate control valve control means for controlling the opening of said second flow control valve to allow the flow of cooling water to the road.

  In the cooling device for an internal combustion engine according to claim 6, the high-temperature cooling water passage connected in parallel to the bypass passage and provided with the high-temperature cooling water reservoir, the bypass passage, and the high-temperature cooling water passage. A second flow rate control valve that controls the flow rate of the cooling water flowing through the high-temperature cooling water passage when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature When the feedback control means performs feedback control so that the temperature of the cooling water approaches the second target water temperature, the cooling water flows to the high-temperature cooling water passage. And a second flow rate control valve control means for controlling the opening degree of the second flow rate control valve so as to permit this.

  In the internal combustion engine cooling apparatus according to claim 7, the heating means is configured to heat the cooling water during a warm-up operation of the internal combustion engine.

  In claim 1, the opening of the flow rate control valve for controlling the flow rate of the cooling water flowing through the radiator passage that circulates the cooling water to the internal combustion engine via the radiator and the bypass passage that bypasses the radiator is determined by the temperature of the cooling water. In the cooling apparatus for an internal combustion engine provided with feedback control means for performing feedback control so as to approach the target water temperature, when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature, the first Since cooling water having a temperature lower than the target water temperature is stored, and when the target water temperature is changed to the second target water temperature lower than the first target water temperature, the stored cooling water is supplied to the internal combustion engine. When the target water temperature of the feedback control means is changed to the second target water temperature, the temperature of the cooling water is quickly brought close to the second target water temperature. Bets can be, it is possible to increase the responsiveness.

  As a result, for example, when the load of the internal combustion engine shifts from a low load to a high load, the internal combustion engine can be cooled quickly, and the anti-knock performance can be improved. Moreover, since abnormal combustion and thermal distortion due to overheating can be prevented, reliability can also be improved. Furthermore, since the charging efficiency of the intake air amount is increased for quick cooling, the output of the internal combustion engine can be improved.

  Since the cooling device for an internal combustion engine according to claim 2 is configured to store the cooling water in the radiator, in addition to the effects described above, no new parts are required, and therefore the configuration is simplified.

  In claim 3, the opening of the flow rate control valve for controlling the flow rate of the cooling water that flows through the radiator passage that circulates the cooling water to the internal combustion engine via the radiator and the bypass passage that bypasses the radiator is determined by the temperature of the cooling water. In the cooling apparatus for an internal combustion engine provided with feedback control means for performing feedback control so as to approach the target water temperature, when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature, the first Cooling water having a temperature higher than the target water temperature is stored in the high temperature cooling water storage section, and when the target water temperature is changed to the second target water temperature higher than the first target water temperature, the cooling water is stored in the high temperature cooling water storage section. When the target water temperature of the feedback control means is changed to the second target water temperature, the cooling water is supplied to the internal combustion engine. Temperature can be quickly brought close to the second target temperature, it is possible to increase the responsiveness.

  As a result, for example, when the load of the internal combustion engine shifts from a high load to a low load, the internal combustion engine can be quickly warmed up, the lubricating oil can be quickly heated to reduce friction, and fuel efficiency can be improved. it can. Moreover, since the temperature of the combustion chamber wall surface also rises, the generation of unburned gas is suppressed, and the emission performance can be improved. Furthermore, since the combustion speed is accelerated according to the rise in the temperature of the combustion chamber wall surface, the fuel consumption performance can be further improved.

  Accordingly, when the internal combustion engine is mounted on a vehicle that is frequently stopped, such as an idle stop vehicle or a hybrid vehicle, the internal combustion engine generates a small amount of heat because the operation time of the internal combustion engine is short. Is particularly effective because it is easy to cool.

  In the internal combustion engine cooling apparatus according to claim 4, since the high-temperature cooling water reservoir is configured to include heating means for heating the cooling water, in addition to the above effects, even when the heat generation amount of the internal combustion engine is small The temperature of the cooling water can be maintained at a high temperature.

  In the cooling device for an internal combustion engine according to claim 5, the flow rate of the cooling water flowing through the second bypass passage provided in parallel with the high temperature cooling water passage provided with the high temperature cooling water storage portion and the high temperature cooling water passage is controlled. And when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature, the flow of the cooling water to the high-temperature cooling water passage is interrupted, When feedback control is performed so as to approach the second target water temperature, the opening of the second flow control valve is controlled so as to permit the flow of the cooling water to the high-temperature cooling water passage. In addition to the effect, at the time of feedback control to the first target water temperature, it is possible to keep the cooling water in the high-temperature cooling water reservoir at a high temperature by blocking the flow of the cooling water to the high-temperature cooling water passage. During the feedback control of the water temperature can be cooling water heated by for example an internal combustion engine that permits the flow of cooling water is supplied to the high-temperature cooling water reservoir, where it held reliably at a high temperature.

  In the cooling device for an internal combustion engine according to claim 6, the second flow rate control valve for controlling the flow rate of the cooling water flowing through the high temperature cooling water passage provided with the high temperature cooling water storage portion connected in parallel to the bypass passage. When the feedback control means performs feedback control so that the temperature of the cooling water is close to the first target water temperature, the flow of the cooling water to the high-temperature cooling water passage is blocked and close to the second target water temperature. When the feedback control is performed, the opening degree of the second flow control valve is controlled so as to permit the flow of the cooling water to the high-temperature cooling water passage. During the feedback control to the target water temperature of 1, the cooling water flow to the high-temperature cooling water passage is interrupted, so that the cooling water in the high-temperature cooling water reservoir can be kept at a high temperature and the feed to the second target water temperature. During back control can hold the cooling water heated by for example an internal combustion engine that permits the flow of cooling water is supplied to the high-temperature cooling water reservoir, where reliably hot.

  In the cooling device for an internal combustion engine according to claim 7, since the heating means is configured to heat the cooling water during the warm-up operation of the internal combustion engine, in addition to the above effects, the heating means is also heated by the heating means during the warm-up operation. The cooling water can be supplied to the internal combustion engine, so there is no need for new heating means and parts for warm-up operation, so the configuration is simple and the warm-up performance during cold warm-up without executing feedback control Can be improved.

  The best mode for carrying out a cooling apparatus for an internal combustion engine according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic view showing a cooling apparatus for an internal combustion engine according to a first embodiment of the present invention.

  In FIG. 1, reference numeral 10 indicates an internal combustion engine (designated as [ENG] in the figure, hereinafter referred to as “engine”) that uses gasoline as fuel and has six cylinders of ignition type water cooling. Although detailed illustration is omitted, the intake air drawn from the air cleaner in the engine 10 passes through the intake pipe to the throttle body 10a, where the flow rate is adjusted by the throttle valve 10b, and the cylinder head (shown as “HEAD”) 10c. It flows toward the combustion chamber of each cylinder of the engine body consisting of a cylinder block (shown as “BLOCK”) 10d.

  The intake air is mixed with the fuel injected by the injector at the intake port in front of the combustion chamber to form an air-fuel mixture. The air-fuel mixture flows into the combustion chamber when the intake valve is opened, and burns when ignited to drive the piston. When the exhaust valve is opened, the exhaust gas generated by the combustion is discharged to the exhaust system, purified by the catalyst device, and released to the outside.

  The engine 10 is mounted on a vehicle (not shown), and a radiator 12 is disposed at the front of the vehicle. Similarly, although the detailed illustration is omitted, the radiator 12 includes a water core composed of a large number of tubes and fins, an upper tank and a lower tank connected to the water core, and water flows from the upper tank to the lower tank via the water core. The cooling water is generated by cooling with wind flowing on the surfaces of the tubes and fins. Further, the radiator 12 includes a fan 12a, and blows wind obtained by driving the fan 12a to the water core.

  As shown in FIG. 1, the engine 10 and the radiator 12 are connected by a radiator passage 14. The radiator passage 14 is connected to the upstream radiator passage 14a, which connects the engine main body and the radiator 12 including the cylinder head 10c and the cylinder block 10d of the engine 10 on the upstream side, and connects the radiator 12 and the engine main body on the downstream side, and the upstream radiator. It consists of a downstream radiator passage 14b continuous with the passage 14a.

  As shown in the figure, the cooling water flows from the engine 10 through the upstream radiator passage 14a to the radiator 12, and returns from the radiator 12 to the engine 10 through the downstream radiator passage 14b. In this way, the cooling water is circulated to the engine 10 via the radiator 12. In the above, “upstream” and “downstream” mean vertical positions in the flow of cooling water with respect to the engine 10.

  The radiator passage 14, that is, the upstream-side radiator passage 14 a and the downstream-side radiator passage 14 b are connected and short-circuited by a bypass passage 16 that bypasses the radiator 12.

  In the downstream radiator passage 14b, on the downstream side of the portion connected to the bypass passage 16, a high-temperature cooling water storage section 20 for storing high-temperature cooling water is provided to form a high-temperature cooling water passage 14b1, and the high-temperature cooling water A second bypass passage 14b2 is provided in parallel with the passage 14b1. The high-temperature cooling water storage unit 20 includes a pipe extending along the exhaust pipe of the engine 10 and generates and stores high-temperature cooling water by exchanging heat with the exhaust. In other words, the high-temperature cooling water storage unit 20 includes a heating unit that heats the cooling water.

  The second bypass passage 14b2 bypasses the high temperature cooling water reservoir 20 and the high temperature cooling water passage 14b1. The second bypass passage 14b2 is provided with a low-temperature cooling water storage unit 22 that stores low-temperature cooling water. The low-temperature cooling water storage unit 22 is configured as a part of an air conditioner that air-conditions the interior of the vehicle.

  In other words, the air conditioner has a reheating unit that once cools the air with the latent heat of vaporization of the refrigerant compressed by the compressor and reheats the cooled air by exchanging heat with the high-temperature cooling water. The cooling water flowing through the bypass passage 14b2 can be used for reheating the heat to exchange the cooling water.

  A water pump 24 is disposed in the vicinity of the position where the downstream radiator passage 14b continues to the engine body. The water pump 24 is connected to an electric motor (not shown), and when driven by the electric motor, the cooling water is forcedly circulated between the engine 10 and the radiator 12 through the downstream radiator passages 14a and 14b. Let

  A first flow control valve (switching valve) 26 is provided at a connection portion between the upstream radiator passage 14 a and the bypass passage 16. The first flow control valve 26 includes a valve body (not shown) driven by an electric motor (not shown). The valve body is connected to the first position where the upstream radiator passage 14a is connected to the radiator 12, and upstream. The radiator passage 14 and the bypass passage 16 are switched by switching between a second position where the side radiator passage 14a is connected to the bypass passage 16 and an arbitrary intermediate position between the first and second positions and changing the opening degree. Control the flow rate of the cooling water flowing through. A part of the cooling water in the upstream radiator passage 14a is also circulated through the throttle body 10a via the throttle circulation passage 14a1 to prevent freezing.

  In the downstream radiator passage 14b, a second flow rate control valve (switching valve) 30 is provided at a connection portion between the high-temperature coolant passage 14b1 and the second bypass passage 14b2. The second flow control valve 30 includes a valve body (not shown) driven by an electromagnetic solenoid (not shown), and selects the high temperature cooling water passage 14b1 of the downstream radiator passage 14b from the valve body. The flow rate of the cooling water flowing through the high-temperature cooling water passage 14b1 and the like is controlled by switching between the first position and the second position where the second bypass passage 14b2 of the downstream radiator passage 14b is selected.

  In the engine 10, an absolute pressure sensor 32 is disposed downstream of the throttle valve 10b to generate an output indicating an absolute pressure in the intake pipe (engine load), and a crank angle sensor 34 is disposed in the vicinity of the crankshaft, and a predetermined crank angle. A pulse signal is output every time. Further, a water temperature sensor 36 is disposed in the vicinity of the cylinder block 10d and generates an output corresponding to the water temperature (cooling water temperature) TW.

  Temperature sensors 40 and 42 are arranged in the high-temperature cooling water storage unit 20 and the low-temperature cooling water storage unit 22, respectively, and generate outputs indicating the temperatures of the cooling water in the high-temperature cooling water storage unit 20 and the low-temperature cooling water storage unit 22, respectively. An accelerator opening sensor 44 is disposed in the vicinity of an accelerator pedal (not shown) in the driver's seat, and generates an output indicating the accelerator opening (accelerator pedal depression amount) operated by the driver.

  The sensor output is sent to an electronic control unit (hereinafter referred to as “ECU”) 50. The ECU 50 is composed of a microcomputer and includes a CPU, a ROM, a RAM, an input / output interface and the like, although not shown. The ECU 50 counts the output of the crank angle sensor 34 and detects the engine speed NE.

  The ECU 50 controls the flow rate by changing the positions of the valve bodies of the first and second flow control valves 26 and 30 based on the operating state of the engine 10 detected through the above-described sensor.

  FIG. 2 is a flowchart showing the control of the ECU 50, which is the operation of the apparatus shown in FIG.

  Explaining below, in S10, it is determined from the output of the accelerator opening sensor 44 whether the operating region of the engine 10 is on the low load side or the high load side.

  When it is determined in S10 that the operation region of the engine 10 is in the low load region, the process proceeds to S12, and the coolant high temperature control is executed. That is, feedback control for feedback control of the opening degree of the first flow control valve 26 so that the detected water temperature (cooling water temperature) TW is close to a high temperature, more precisely, to the first target water temperature (for example, 100 ° C.). Execute.

  Specifically, the valve body of the first flow rate control valve 26 is controlled to a second position where the upstream radiator passage 14a is connected to the bypass passage 16, and the valve body of the second flow rate control valve 30 is heated to high-temperature cooling water. It controls to the 1st position which chooses passage 14b1. That is, the inside of the engine 10 is circulated without supplying cooling water to the radiator 12. Thereby, the temperature of the cooling water is raised by the amount of heat generated by the engine 10.

  When the detected water temperature TW is equal to or lower than the first target water temperature (100 ° C.), the ECU 50 controls the valve body of the first flow control valve 26 to the above position and exceeds the first target water temperature. Decreases the water temperature TW by directing the valve body to the first position where the upstream radiator passage 14a and the radiator 12 are connected or to an intermediate position between the first position and the second position (changing the opening degree). Thereafter, by repeating the above-described operation, feedback control is performed in which the opening degree of the first flow control valve 26 is feedback-controlled so that the detected water temperature TW approaches the first target water temperature.

  Further, the valve body of the second flow rate control valve 30 is controlled to the first position for selecting the high-temperature cooling water passage 14b1 of the downstream radiator passage 14b, and the cooling water is brought into the engine 10 through the high-temperature cooling water passage 14b1. While circulating, the cooling water in the low temperature cooling water storage part 22 of the 2nd bypass passage 14b2 is stored without circulating inside the engine 10, and it cools there.

  The temperature of the cooling water stored in the low-temperature cooling water storage unit 22 only needs to be lower than the first target water temperature (100 ° C.), and is low to about the second target water temperature (80 ° C.) which is a target value at the time of high load described later. It is not necessary. The temperature of the low-temperature cooling water reservoir 22 is detected via the temperature sensor 42.

  On the other hand, when it is determined in S10 that the operation region of the engine 10 is in the high load region, the process proceeds to S14 and the cooling water low temperature control is executed. That is, the opening degree of the first flow control valve 26 is feedback-controlled so that the detected water temperature (cooling water temperature) TW is close to the low temperature, more precisely, the second target water temperature (for example, 80 ° C.). Execute feedback control.

  Specifically, the valve body of the first flow rate control valve 26 is controlled to the first position where the upstream side radiator passage 14a and the radiator 12 are connected, and the valve body of the second flow rate control valve 30 is controlled to the downstream radiator passage 14b. The second bypass passage 14b2 is controlled to the second position. That is, after supplying cooling water to the radiator 12, the inside of the engine 10 is circulated through the second bypass passage 14b2. Thereby, the cooling water is cooled by the radiator 12 and the temperature is lowered.

  While the detected water temperature TW exceeds the second target water temperature (80 ° C.), the ECU 50 controls the valve body of the first flow rate control valve 26 to the first position and lower than the second target water temperature. When it decreases, the water temperature TW is raised again toward the second position where the valve body is connected to the bypass passage 16 or the intermediate position thereof (the opening degree is changed). Thereafter, by repeating the above-described operation, feedback control is performed in which the opening degree of the first flow control valve 26 is feedback-controlled so that the detected water temperature TW approaches the second target water temperature.

  Further, as described above, the valve body of the second flow rate control valve 30 is controlled to the second position where the second bypass passage 14b2 of the downstream radiator passage 14b is selected, and the cooling water is supplied to the engine via the second bypass passage 14b2. The coolant in the high-temperature coolant storage section 20 of the high-temperature coolant passage 14b1 is stored without being circulated in the engine 10 and heated there.

  The temperature of the cooling water stored in the high-temperature cooling water storage unit 20 only needs to be higher than the second target water temperature (80 ° C.), and is about the first target water temperature (100 ° C.) that is the target value at the time of the low load described above. It does not have to be expensive. The temperature of the high-temperature cooling water reservoir 20 is detected via the temperature sensor 40.

  FIG. 3 is a flowchart showing the control of the ECU 50 executed in parallel with FIG.

  In S100, it is determined whether or not the operation region has been changed, in other words, whether or not the target water temperature needs to be changed. If the result is negative, the subsequent processing is skipped. Judge whether the change from high to high load.

  When the result in S102 is affirmative, the program proceeds to S104, and the cooling water cooled in the low-temperature cooling water storage unit 22 is supplied to the engine 10.

  This will be described. When the target water temperature of the feedback control is changed to the second target water temperature (80 ° C.) lower than the first target water temperature in accordance with the change from the low load region to the high load region, the temperature of the cooling water Takes time to change.

  Therefore, when feedback control is performed so that the temperature of the cooling water approaches the first target water temperature (100 ° C.) at low load, cooling water having a temperature lower than the first target water temperature is supplied to the low-temperature cooling water storage unit 22. In response to the change to a high load, the cooling water stored in the low-temperature cooling water storage unit 22 is supplied to the engine 10 to quickly bring the temperature of the cooling water close to the second target water temperature, thereby improving the responsiveness. I tried to raise it.

  Next, the process proceeds to S106, and the cooling water low-temperature control described in S14 of the flowchart of FIG. 2 is executed. At that time, cooling water is supplied to the high-temperature cooling water reservoir 20 and heated (not circulated through the engine 10).

  On the other hand, when the result in S102 is negative, since the load is changed from the high load to the low load region, the process proceeds to S108, and the cooling water heated in the high-temperature cooling water storage unit 20 is supplied to the engine 10.

  That is, when the target water temperature of the feedback control is changed to the first target water temperature (100 ° C.) higher than the second target water temperature (80 ° C.) with the change from the high load to the low load, the temperature of the cooling water is changed. It takes time to reach it.

  Therefore, when feedback control is performed so that the temperature of the cooling water approaches the second target water temperature (80 ° C.) at the time of high load, the cooling water having a temperature higher than the second target water temperature is supplied to the high-temperature cooling water reservoir 20. In response to the change to a low load, the cooling water stored in the high-temperature cooling water storage unit 20 is supplied to the engine 10 to quickly bring the temperature of the cooling water close to the first target water temperature, thereby improving the responsiveness. I tried to raise it.

  Next, in S110, the above-described cooling water high temperature control described in S12 of the flowchart of FIG. 2 is executed. At that time, cooling water is supplied to the low-temperature cooling water reservoir 22 and cooled (similarly, it is not circulated through the engine 10).

  As described above, in the first embodiment, when feedback control is performed so that the temperature of the cooling water approaches the first target water temperature (100 ° C.), the cooling water having a temperature lower than the first target water temperature is stored. At the same time, when the target water temperature is changed to the second target water temperature (80 ° C.) lower than the first target water temperature, the stored cooling water is supplied to the engine 10. When the target water temperature is changed to 2, the temperature of the cooling water can be quickly brought close to the second target water temperature, and the responsiveness can be improved.

  Specifically, when the load of the engine 10 shifts from a low load to a high load, the engine 10 can be quickly cooled, and the anti-knock performance can be improved. Moreover, since abnormal combustion and thermal distortion due to overheating can be prevented, reliability can also be improved. Furthermore, since the charging efficiency of the intake air amount is increased for quick cooling, the output of the engine 10 can be improved.

  In addition, when feedback control is performed so that the temperature of the cooling water approaches the second target water temperature (80 ° C.), cooling water having a temperature higher than the second target water temperature is stored in the high-temperature cooling water storage unit 20. When the target water temperature is changed to the first target water temperature (100 ° C.) higher than the second target water temperature, the cooling water stored in the high-temperature cooling water storage unit 20 is configured to be supplied to the engine 10. When the target water temperature for feedback control is changed to the first target water temperature, the temperature of the cooling water can be quickly brought close to the first target water temperature, and the responsiveness can be improved.

  Specifically, when the load of the engine 10 shifts from a high load to a low load, the engine 10 can be warmed up quickly, the lubricating oil can be quickly heated to reduce friction, and fuel efficiency can be improved. it can. Moreover, since the temperature of the combustion chamber wall surface also rises, the generation of unburned gas is suppressed, and the emission performance can be improved. Furthermore, since the combustion speed is accelerated according to the rise in the temperature of the combustion chamber wall surface, the fuel consumption performance can be further improved.

  Therefore, when the internal combustion engine is mounted on a vehicle that is frequently stopped, such as an idle stop vehicle or a hybrid vehicle, the engine 10 is operated for a short time, so that the heat generated by the engine 10 is small. Is particularly effective because it is easy to cool.

  Further, since the high-temperature cooling water reservoir 20 is configured to include a heating means for heating the cooling water, in addition to the above-described effects, the temperature of the cooling water can be maintained at a high temperature even when the amount of heat generated by the engine 10 is small. it can.

  Further, a second flow rate control valve 30 for controlling the flow rate of the cooling water flowing through the second bypass passage 14b2 provided in parallel with the high temperature cooling water passage 14b1 and the high temperature cooling water passage 14b1 provided with the high temperature cooling water reservoir 20 is provided. And when the feedback control is performed so that the temperature of the cooling water approaches the second target water temperature (80 ° C.), the flow of the cooling water to the high-temperature cooling water passage 14b1 is interrupted, and the first target water temperature (100 Since the opening degree of the second flow control valve 30 is controlled so as to permit the flow of the cooling water to the high-temperature cooling water passage 14b1 when the feedback control is performed so as to be close to (° C.). In addition, at the time of feedback control to the second target water temperature, the cooling water in the high-temperature cooling water reservoir 20 is kept at a high temperature by blocking the flow of the cooling water to the high-temperature cooling water passage 14b1. In addition, when the feedback control to the first target water temperature is possible, the coolant water heated by the engine 10, for example, is supplied to the high-temperature coolant storage unit 20 by allowing the coolant to flow, and is reliably maintained at a high temperature there. Can do.

  That is, even after the heated cooling water is supplied to the engine 10 in S108 of FIG. 4, the cooling water is always circulated inside the engine 10 through the high temperature cooling water passage 14b1 during the high temperature control. Therefore, when switching to low temperature control and the high temperature cooling water passage 14b1 is closed thereafter, high temperature (100 ° C.) cooling water can be stored. Therefore, high-temperature cooling water can be stored without extra heating by the heating device.

  Further, since the heating means is configured to heat the cooling water during the warm-up operation of the engine 10, in addition to the above-described effects, the cooling water heated by the heating means can be supplied to the engine 10 during the warm-up operation. Since new heating means and parts for machine operation are not required, the configuration is simplified, and warm-up performance during cold warm-up without executing feedback control can be improved.

  Moreover, the high temperature cooling water storage part 20 or the low temperature cooling water storage part 22 is located downstream of the connection part of the radiator passage 14 and the bypass passage 16, that is, the arrangement position of the second flow control valve 30, in other words. Since it is located on the side closer to the engine main body, it is possible to quickly supply the high-temperature or low-temperature cooling water stored in accordance with the change in the target water temperature to the engine main body and quickly approach the target water temperature.

  FIG. 4 is a schematic view similar to FIG. 1 showing the overall internal combustion engine cooling apparatus according to the second embodiment of the present invention.

  The description will focus on the differences from the first embodiment. In the second embodiment, the high-temperature cooling water reservoir 20 of the first embodiment, the high-temperature cooling water passage 14b1 in which the high-temperature cooling water reservoir 14b is provided, and the low-temperature cooling water. The second bypass passage 14b2 and the second flow rate control valve 30 provided with the storage portion 22, the high temperature cooling water passage 14b1 and the low temperature cooling water storage portion 22 are removed.

  Therefore, in the second embodiment, the radiator 12 is used as the low-temperature cooling water reservoir 22 that stores low-temperature cooling water. In this case, during high-temperature control, the fan 12a is driven during deceleration or the like to increase the air volume to the water core, and the cooling water temperature inside the radiator 12 is maintained at a value lower than the first target water temperature. I will let you.

  Thus, since it comprised so that cooling water might be stored in the radiator 12, compared with the structure of 1st Example, since a new part is not required, a structure also becomes simple. The remaining configuration and effects are not different from those of the first embodiment.

  FIG. 5 is a schematic view similar to FIG. 1 showing the overall internal combustion engine cooling apparatus according to the third embodiment of the present invention.

  If it demonstrates focusing on a different point from 1st Example, in the 3rd Example, the low temperature cooling water storage part 22 was removed. That is, also in the third embodiment, the radiator 12 is used as the low-temperature cooling water storage section 22 that stores low-temperature cooling water, and the cooling water is stored in the radiator 12. As a result, as in the second embodiment, since no new parts are required, the configuration is simplified.

  Further, the third embodiment includes a high-temperature cooling water passage 16a connected in parallel to the bypass passage 16 and provided with the high-temperature cooling water reservoir 20, and the bypass passage is similar to the process shown in the flow chart of FIG. When the flow rate of the cooling water flowing from 16 to the high-temperature cooling water passage 16a is controlled by the second flow rate control valve 30, feedback control is performed so that the temperature of the cooling water approaches the second target water temperature (80 ° C.). Shuts off the flow of cooling water to the high-temperature cooling water passage 16a and permits the flow of cooling water to the high-temperature cooling water passage 16a when feedback control is performed so as to approach the first target water temperature (100 ° C.). In this way, the opening degree of the second flow control valve 30 is controlled.

  Thus, as in the first embodiment, the cooling water in the high-temperature cooling water reservoir 20 is blocked by blocking the flow of the cooling water to the high-temperature cooling water passage 16a during feedback control to the second target water temperature (80 ° C.). Can be maintained at a high temperature, and at the time of feedback control to the first target water temperature (100 ° C.), for example, the cooling water heated by the engine 10 is supplied to the high-temperature cooling water reservoir 20 by allowing the circulation of the cooling water, Next, when the temperature is changed to the second target water temperature, the cooling water can be kept at a high temperature. The remaining configuration and effects are not different from those of the first embodiment.

  As described above, in the first, second, and third embodiments, the radiator passage 14 that circulates cooling water to the internal combustion engine (engine) 10 via the radiator 12, and the bypass passage 16 that bypasses the radiator, The (first) flow control valve 26 for controlling the flow rate of the cooling water flowing through the radiator passage 14 and the bypass passage 16 and the opening of the flow control valve so that the temperature of the cooling water approaches the target water temperature. In a cooling apparatus for an internal combustion engine provided with feedback control means (ECU 50, S10 to S14) for feedback control, feedback control is performed so that the feedback control means brings the temperature of the cooling water closer to a first target water temperature (100 ° C.). A low-temperature cooling water storage unit that stores cooling water having a temperature lower than the first target water temperature in the low-temperature cooling water storage unit 22. When the target water temperature of the means (ECU 50, S12) and the feedback control means is changed to the second target water temperature (80 ° C.) lower than the first target water temperature, it is stored in the low-temperature cooling water storage unit 22. Low temperature cooling water supply means (ECU 50, S102, S104) for supplying cooling water to the internal combustion engine is provided.

  In the first embodiment, the air-conditioning system has reheating means for once cooling the air by the latent heat of vaporization of the refrigerant compressed by the compressor and reheating the cooled air by exchanging heat with high-temperature cooling water. In addition to the apparatus, the low-temperature cooling water storage unit 22 is configured to include reheating means of the air conditioner.

  In the second and third embodiments, the low-temperature cooling water storage unit 22 is configured to include the radiator.

  In the first and third embodiments, a radiator passage 14 for circulating cooling water to the internal combustion engine (engine) 10 via the radiator 12, a bypass passage 16 for bypassing the radiator 12, and the radiator passage 14 and a (first) flow control valve 26 for controlling the flow rate of the cooling water flowing through the bypass passage 16 and feedback for feedback control of the opening degree of the flow control valve so that the temperature of the cooling water approaches the target water temperature. In a cooling apparatus for an internal combustion engine provided with control means (ECU 50, S10 to S14), when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature (80 ° C.). The high-temperature cooling water storage means (E) stores the cooling water having a temperature higher than the first target water temperature in the high-temperature cooling water storage unit 20. U50, S14) and when the target water temperature of the feedback control means is changed to the second target water temperature (100 ° C.) higher than the first target water temperature, the cooling water stored in the high-temperature cooling water storage unit is High temperature cooling water supply means (ECU 50, S102, S108) for supplying to the internal combustion engine is provided.

  In the first and third embodiments, the high-temperature cooling water reservoir 20 is configured to include heating means for heating the cooling water.

  Further, in the first embodiment, in the downstream radiator passage 14b provided downstream of the portion connected to the bypass passage 16 downstream of the radiator 12, and in the downstream radiator passage 14b, the high-temperature cooling water storage is performed. The high-temperature cooling water passage 14b1 in which the section 20 is provided, the second bypass passage 14b2 provided in parallel with the high-temperature cooling water passage, and the flow rate of the cooling water flowing through the high-temperature cooling water passage and the second bypass passage are controlled. When the second flow rate control valve 30 and the feedback control means perform feedback control so that the temperature of the cooling water is brought close to the first target water temperature (80 ° C.), the high-temperature cooling water passage 14b1 The flow of the cooling water is interrupted, and the feedback control means brings the temperature of the cooling water close to the second target water temperature (100 ° C.). The second flow rate control valve control means (ECU 50,) for controlling the opening of the second flow rate control valve so as to permit the flow of the cooling water to the high temperature cooling water passage 14b1. S12, S14).

  In the third embodiment, the high-temperature cooling water passage 16a, which is connected in parallel to the bypass passage 16 and in which the high-temperature cooling water reservoir 20 is provided, the bypass passage 16 and the high-temperature cooling water passage 16a are provided. When the second flow rate control valve 30 for controlling the flow rate of the flowing cooling water and the feedback control means perform feedback control so that the temperature of the cooling water approaches the first target water temperature (80 ° C.) When the flow of the cooling water to the high-temperature cooling water passage 16a is interrupted and the feedback control means performs feedback control so that the temperature of the cooling water approaches the second target water temperature (100 ° C.), the high temperature Second flow control valve control means (ECU 5) for controlling the opening of the second flow control valve 30 so as to permit the flow of the cooling water to the cooling water passage 16a. It was composed as comprising a S12, S14) and.

  The heating means is configured to heat the cooling water when the internal combustion engine (engine) 10 is warmed up.

  In the above description, the high-temperature cooling water reservoir 20 is configured to use exhaust heat, but an electric heater may be used.

  Moreover, although the water pump 24 is configured to be driven by the electric motor, it may be mechanically driven by being connected to the engine 10.

  The first flow control valve 26 is driven by the electric motor, but may be driven by a negative pressure or an electromagnetic solenoid. The second flow control valve 30 is also driven by an electromagnetic solenoid, but may be driven by a negative pressure or an electric motor.

  Further, the load of the engine 10 is determined from the accelerator opening, but the intake air amount is detected from the intake pipe pressure and the engine speed, or an air flow meter is provided, and from the engine speed and the throttle valve 10b. You may judge from the detected value obtained by detecting an opening degree.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing an overall internal combustion engine cooling apparatus according to a first embodiment of the present invention; It is a flowchart which shows operation | movement of the apparatus shown in FIG. Similarly, it is a flowchart which shows operation | movement of the apparatus shown in FIG. FIG. 3 is a schematic view similar to FIG. 1, generally showing a cooling apparatus for an internal combustion engine according to a second embodiment of the present invention. FIG. 3 is a schematic view similar to FIG. 1, generally showing a cooling apparatus for an internal combustion engine according to a third embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Internal combustion engine (engine), 12 Radiator, 12a Fan, 14 Radiator passage, 14a Upstream radiator passage, 14b Downstream radiator passage, 14b1 High temperature cooling water passage, 14b2 Second bypass passage, 16 Bypass passage, 20 High temperature cooling water Reservoir, 22 Low temperature cooling water reservoir, 26 First flow control valve, 30 Second flow control valve, 32 Absolute pressure sensor, 34 Crank angle sensor, 36 Water temperature sensor, 44 Accelerator opening sensor, 50 Electronic control unit (ECU)

Claims (7)

  A radiator passage for circulating cooling water through the radiator to the internal combustion engine, a bypass passage for bypassing the radiator, a flow rate control valve for controlling a flow rate of the cooling water flowing through the radiator passage and the bypass passage, and the cooling water An internal combustion engine cooling apparatus comprising feedback control means for feedback-controlling the opening degree of the flow rate control valve so that the temperature approaches the target water temperature, wherein the feedback control means changes the temperature of the cooling water to the first target water temperature. When feedback control is performed so as to approach, low-temperature cooling water storage means for storing cooling water having a temperature lower than the first target water temperature in the low-temperature cooling water storage section, and the target water temperature of the feedback control means is the first water temperature. The cooling water stored in the low-temperature cooling water reservoir when the second target water temperature is lower than the target water temperature A cooling apparatus for an internal combustion engine, characterized in that a low-temperature cooling water supply means for supplying to the internal combustion engine.   The cooling device for an internal combustion engine according to claim 1, wherein the low-temperature cooling water storage section includes the radiator.   A radiator passage for circulating cooling water through the radiator to the internal combustion engine, a bypass passage for bypassing the radiator, a flow rate control valve for controlling a flow rate of the cooling water flowing through the radiator passage and the bypass passage, and the cooling water An internal combustion engine cooling apparatus comprising feedback control means for feedback-controlling the opening degree of the flow rate control valve so that the temperature approaches the target water temperature, wherein the feedback control means changes the temperature of the cooling water to the first target water temperature. When feedback control is performed so as to approach, the high-temperature cooling water storage means for storing cooling water having a temperature higher than the first target water temperature in the high-temperature cooling water storage section, and the target water temperature of the feedback control means is the first water temperature. The cooling water stored in the high-temperature cooling water reservoir when the second target water temperature is higher than the target water temperature A cooling apparatus for an internal combustion engine, characterized in that a high-temperature cooling water supply means for supplying to the internal combustion engine.   The cooling device for an internal combustion engine according to claim 3, wherein the high-temperature cooling water storage unit includes a heating unit that heats the cooling water.   A downstream radiator passage provided downstream of a portion connected to the bypass passage downstream of the radiator, a high temperature cooling water passage in which the high temperature cooling water storage section is provided in the downstream radiator passage, and the high temperature cooling water passage A second bypass passage provided in parallel, a second flow rate control valve for controlling a flow rate of the cooling water flowing through the high temperature cooling water passage and the second bypass passage, and the feedback control means includes the cooling water. When feedback control is performed so that the temperature approaches the first target water temperature, the flow of the cooling water to the high-temperature cooling water passage is interrupted, and the feedback control means controls the temperature of the cooling water to the second temperature. When the feedback control is performed so as to be close to the target water temperature, the second water temperature is allowed to flow through the high-temperature cooling water passage. The cooling system of an internal combustion engine according to claim 3, wherein further comprising a second flow control valve control means for controlling the opening of the flow control valve.   A high-temperature cooling water passage connected in parallel to the bypass passage and provided with the high-temperature cooling water reservoir, and a second flow control valve for controlling the flow rate of the cooling water flowing through the bypass passage and the high-temperature cooling water passage And when the feedback control means performs feedback control so that the temperature of the cooling water approaches the first target water temperature, the flow of the cooling water to the high-temperature cooling water passage is interrupted, and the feedback control means Is performing feedback control so that the temperature of the cooling water approaches the second target water temperature, the degree of opening of the second flow control valve so as to permit the flow of the cooling water to the high-temperature cooling water passage. 5. A cooling apparatus for an internal combustion engine according to claim 3, further comprising second flow rate control valve control means for controlling the flow rate.   The cooling device for an internal combustion engine according to claim 4, wherein the heating means heats the cooling water during a warm-up operation of the internal combustion engine.

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