JP2018178895A - Vehicle engine cooling control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine cooling control device of a vehicle, which effectively suppresses a temperature rise on the equipment provided in the exhaust system of an engine and in an engine room when the operation of the engine is stopped, on the basis of the latest travel state of the vehicle just before the engine stop.SOLUTION: An engine cooling control device of a vehicle has: a first cooling circuit part 67 having a main radiator 71 for cooling cooling water of an engine 5 and a main radiator fan 73; a second cooling circuit part 69 having a sub-cooling circuit 84 for circulating a cooling medium between a sub-radiator 79 for cooling equipment 11 provided in the exhaust system of the engine and the equipment 11 by a circulation pump 85, and a sub-radiator fan 81; and a control means 89 for controlling the first cooling circuit part and the second cooling circuit part when the operation of the engine is stopped, on the basis of the degree of a cooling requirement which is determined based on latest history information just before the engine stop.SELECTED DRAWING: Figure 1

Description

  The present invention relates to improvement of an engine cooling control device for a vehicle that cools an engine and equipment provided in an engine exhaust system as needed after engine operation is stopped.

In general, a vehicle has a radiator provided in an engine room to circulate cooling water between the radiator and the engine during engine operation to cool the engine or to cool the engine room with a radiator fan of the radiator. ing.
However, in the case of a vehicle in which the engine is supercharged, that is, in the case where the exhaust system of the engine is equipped with a device such as a turbocharger (device performing supercharge operation), the operation of the engine is stopped and circulation of cooling water and the engine When the room is not cooled, the turbocharger, which has been operated by the exhaust heat energy of the engine, is not cooled, so the heat of the engine and the turbocharger rapidly increases the ambient temperature of the engine room. For this reason, when the engine operation is stopped, various devices disposed in the engine room may be thermally affected (heat damage).

  Therefore, as a countermeasure against heat damage, in a vehicle equipped with a turbocharger conventionally, a dedicated water cooling system for circulating the cooling water by a pump to a turbocharger provided in an exhaust system of the engine as disclosed in Patent Document 1 A plurality of cooling devices such as a device and a bonnet fan are provided to control the radiator fan of the radiator that cools the pump, bonnet fan and radiator according to the engine lubricating oil temperature and the coolant temperature at the turbocharger outlet when the engine shuts down. Technology has been proposed for cooling the engine, turbocharger, and engine compartment.

Japanese Patent Application Laid-Open No. 01-177416

However, when the operation of the engine as in Patent Document 1 is stopped, the operation of the plurality of cooling devices is performed by the temperature of the lubricating oil of the engine and the cooling water temperature at the outlet of the turbocharger which is a device provided in the engine exhaust system. The control technology is not effective because it is a technology that controls by focusing only on the temperature of the lubricating oil temperature of the turbocharger and the temperature of the cooling water when the engine is shut down.
That is, the temperatures of the engine, the turbocharger and the engine room at the time of engine operation stop differ depending on the vehicle operation state until the operation of the engine stops, that is, the traveling state of the vehicle immediately before the engine operation stop.

  For example, in the case of traveling at a low vehicle speed where the ventilation of the traveling wind can not be expected in the engine room and traveling with a large traveling load, for example, climbing up a steep slope, as the latest traveling state until the operation of the engine stops. If the operation of the engine is stopped immediately after the climbing, the engine room, the engine, the turbocharger, etc. tend to be quite hot since cooling during operation by the traveling wind of the engine room can not be expected.

On the contrary, immediately after high-speed traveling when traveling with a small traveling load, for example, traveling on a flat road at high speed, with a high vehicle speed at which traveling wind can be expected in the engine room. When the operation of the engine is stopped, the engine room, the engine and the turbocharger are cooled by the traveling wind while the vehicle is traveling, and the temperature rise tends to be suppressed.
In other words, the temperature of the engine, turbochargers (devices attached to the engine exhaust system), and the engine room, which cause heat damage, are at the time of engine operation stop from low and medium speed travel and at engine stop from high speed travel. Depending on the latest driving condition of the vehicle until the engine operation is stopped.

However, just by controlling a plurality of cooling devices according to engine lubricating oil temperature when engine operation is stopped as in Patent Document 1 and cooling water temperature at the outlet of the turbocharger, heat damage caused by such temperature rise Can not respond properly to
Therefore, it is an object of the present invention to effectively suppress the temperature rise of the engine, the devices provided in the exhaust system of the engine, and the engine room based on the most recent driving condition of the vehicle immediately before the engine stops. An engine cooling control device for a vehicle is provided.

  According to an aspect of the present invention, an engine includes: an engine housed in an engine room; a main radiator for cooling engine cooling water; a first cooling circuit unit having a main radiator fan for blowing cooling air to the engine room through the main radiator; A sub-cooler for cooling equipment provided in the exhaust system of the air conditioner, a sub-cooling circuit for circulating a cooling medium with the circulation pump between the above-mentioned equipment, and a sub-radiator fan for blowing cooling air to the engine room through the sub-radiator 2 Cooling circuit unit, history means for recording the traveling state of the vehicle from engine operation to stop as history, and when engine operation is stopped, cooling request degree based on the latest history information just before engine stop And the first cooling based on the determination of the degree of demand for cooling by the determining means. In that and a control unit for controlling the circuit unit and the second cooling circuit.

  According to the present invention, when the operation of the engine is stopped, the main radiator and the main radiator fan (all in the first cooling circuit unit), the sub radiator, the sub radiator fan and the circulation pump (in the second cooling circuit unit) Since control is performed based on the cooling request condition determined by the latest operation history information immediately before the stop, the engine, equipment provided in the exhaust system of the engine, and the engine room are properly adapted Can be cooled.

  Therefore, the temperature rise of the engine, the devices provided in the exhaust system of the engine, and the engine room can be effectively suppressed, and heat damage can be properly dealt with.

The block diagram which shows the engine cooling control apparatus which becomes an aspect which concerns on one Embodiment of this invention. The block diagram which shows the control circuit of the same apparatus. The flowchart explaining the control of the 1st, 2nd cooling circuit unit based on the driving | running | working state immediately before the engine operation stop of the same apparatus. FIG. 7 is a plan view for explaining the cooling state in the engine room when the engine is stopped from traveling at low and medium vehicle speeds with a large traveling load of the vehicle. FIG. 7 is a plan view for explaining the cooling state in the engine room when the engine stops from traveling at a high vehicle speed with a small traveling load of the vehicle.

Hereinafter, the present invention will be described based on an embodiment shown in FIG. 1 to FIG.
Fig.1 (a) shows the front part of vehicles, such as a car, FIG.1 (b) shows the structure of each apparatus mounted in the engine room of the front of the said vehicle, 1 in FIG. 1 is the said vehicle The car body 3 is an engine room formed at the front of the car body 1, and 5 is a reciprocating engine (multi-cylinder) housed in the engine room 3. Incidentally, in FIG. 1 (a), the symbol F indicates the front side of the vehicle, and the symbol Rha indicates the rear side of the vehicle.

  In the engine 5, the intake side with the intake manifold 7 is directed to the traveling air inlet 9 side formed in the front of the vehicle body, and the exhaust side with the exhaust manifold 8 (partially shown in FIG. It is installed in the engine room 3 adjacent to the vehicle compartment 1a side (only a part of which is shown). An exhaust manifold 8 forming an exhaust system of the engine 5 is provided with a turbocharger 11 (corresponding to a device provided in the engine exhaust system of the present application) for performing a supercharging operation of the engine 5. That is, the engine 5 is housed in the engine room 3 in a horizontal position in which the turbocharger 11 is located on the side of the passenger compartment 1a. Incidentally, a water-cooled intercooler 13 is disposed above the engine 5.

  The respective components will be described in detail. As shown in FIG. 1B, the engine 5 can reciprocate the cylinder 17, which houses the piston 15, the crankshaft 21 connected with the piston 15 and the connecting rod 19, and the crank A cylinder block 25 having a water pump 23 driven by the axial torque of the shaft 21, an oil pan 27 combined with the lower part of the cylinder block 25, a combustion chamber 29 combined with the head of the cylinder block 25, A cylinder head 41 having exhaust ports 31, 33, intake / exhaust valves 35, 37, an intake / exhaust valve mechanism (not shown), an ignition plug 39, a fuel injection nozzle (not shown), etc. Configured Incidentally, a cooling water passage 43 is formed inside the cylinder block 25 and the cylinder head 41, and the cooling water passage 43 communicates with the water pump 23.

  The turbocharger 11 coaxially connects a compressor wheel 49 contained in the compressor housing 47 forming the compressor side 11 a and a turbine wheel 53 contained in the turbine housing 51 forming the turbine side 11 b with a shaft member 55. The shaft member 55 is rotatably supported by a bearing unit 57. The bearing unit 57 is formed with a cooling water passage 59 for cooling the turbocharger 11 which has a high temperature.

  The intake manifold 7 of the engine 5 is connected to the air cleaner 62 via the throttle valve 61, the intercooler 13, and the compressor housing 47 of the turbocharger 11, and intake air can be taken in from the air cleaner 62. 60 shows an intake passage. The exhaust manifold 8 of the engine 5 is connected to the catalyst 63 via a turbine housing 51 of the turbocharger 11, and the exhaust gas from the engine 5 is exhausted through the turbocharger 11 and the catalyst 63. Reference numeral 64 denotes an exhaust passage through which exhaust gas of the engine 5 flows. As a result, in the turbocharger 11, when the turbine wheel 53 receives the exhaust heat energy of the engine 5, the compressor wheel 49 is driven to perform a supercharging operation in which the intake air is pushed into the combustion chamber 29.

On the other hand, at the traveling air inlet 9 of the engine room 3, a main radiator device 67 (corresponding to a first cooling circuit portion of the present application) which is an apparatus configuring an engine cooling control device A cooling circuit portion is provided side by side in the vehicle width direction.
Specifically, the main radiator device 67 is, for example, a plurality of main radiators 71 disposed between the traveling air inlet 9 and the engine 5 and a plurality of heat radiators disposed between the heat exchanger of the main radiator 71 and the engine 5. And a main radiator fan 73 composed of an electric fan. The main radiator 71 is disposed to occupy most of one side of the traveling air inlet 9. The main radiator 71 communicates with the water pump 23 and the cooling water passage 43 of the engine 5 via the main passage 75 extending from the main radiator 71. That is, the engine 5 is cooled by the cooling water (cooling medium) circulated by the water pump 23. Incidentally, the main radiator fan 73 blows the outside air as cooling air to the engine room 3 through the main radiator 71.

  The sub radiator device 69 is configured, for example, by diverting a water-cooled intercooler cooling device 77. For example, the intercooler cooling device 77 is an electric fan disposed between the sub radiator 79 adjacent to the main radiator 71 and arranged in the vehicle width direction and the heat exchange portion of the sub radiator 79 and the engine 5 And a sub-radiator fan 81. The sub radiator device 69 has a smaller cooling capacity than the main radiator device 67. For this reason, the sub radiator 79 has a smaller heat exchange portion than the main radiator 71, and one sub radiator fan 81 is provided for two main radiator fans 73. The sub passage 83 extending from the sub radiator 79 leads to the intercooler 13. A circulation pump 85 formed of, for example, an electric pump is interposed in the sub passage 83, and the intercooler 13 is cooled by the cooling water (cooling medium) sent from the sub radiator 79. That is, the supercharged intake air is cooled by the intercooler 13.

  Further, a turbo cooling passage 86 (corresponding to the flow passage of the present invention) extends from the intercooler 13. The turbo cooling passage 86 is connected to the cooling water passage 59 of the turbocharger 11, and the cooling water from the sub radiator 79 returns to the sub radiator 79 via the turbocharger 11 (corresponding to the sub cooling circuit of the present application) Are configured. Thus, the turbocharger 11 is cooled by the cooling water (cooling medium) circulating in the sub radiator 79. That is, in the sub radiator device 69 using the intercooler cooling device 77, cooling of the turbocharger 11 is performed.

  Of course, the engine compartment 3, the engine 5 and the turbocharger 11 are cooled by the cooling air from the main radiator fan 73 and the sub radiator fan 81. Further, both the main radiator fan 73 and the sub radiator fan 81 are disposed at positions where the cooling air is directly blown to the engine 5, and the cooling air blown out from the main radiator fan 73 and the sub radiator fan 81 is effective. The engine 5 and the turbocharger 11 are cooled.

  The vehicle is also provided with an engine cooling control device 87 having a configuration as shown in the block diagram of FIG. 2 in order to prevent heat damage (mainly due to turbocharger operation stop) at the time of engine stop. The engine cooling control device 87 controls the main radiator device 67 and the sub radiator device 69 based on the history information of the vehicle operating state immediately before the engine stop when the vehicle stops and the operation of the engine 5 stops. is there.

Specifically, the engine cooling control device 87 includes, for example, an ECU 89 (corresponding to a control unit of the present application) configured by a microcomputer. Each device is connected to the ECU 89 as shown in FIG.
Specifically, the engine cooling water temperature sensor 91 (hereinafter referred to as E / G water temperature sensor 91: FIG. 1) that detects the cooling water temperature of the engine 5 in the ECU 89, and the turbocharger outlet water temperature that detects the outlet cooling water temperature of the turbocharger 11 Sensor 93 (hereinafter referred to as T / C water temperature sensor 93: FIG. 1), exhaust temperature sensor 95 (FIG. 1) for detecting the temperature of the exhaust gas at the outlet of the turbocharger 11, vehicle speed sensor 97 for detecting the vehicle speed of the vehicle A gradient sensor 99 for detecting a road surface gradient in the inside, an ignition key switch 101 (hereinafter referred to as an I / G switch 101) for turning on and off the engine 5, a main radiator fan 73, a sub radiator fan 81, a circulation pump 85 and the like are connected.

  Further, in the ECU 89, a history function (corresponding to the history means of the present application) for storing, as a history, the traveling state of the vehicle from when the engine 5 is driven until it is stopped is set. In particular, the history function is an engine that includes information on the driving load of the engine 5, including slope traveling on a slope, road surface slope information at the time of traveling, for example, climbing speed per unit time, and vehicle speed information serving as ventilation information on the engine room 3. It is assumed that the traveling state from when the engine 5 starts driving until the engine 5 stops is recorded.

Of course, the ECU 89 also has an engine stop detection function for detecting a vehicle stop and an engine stop based on on / off information of the I / G switch 101 and vehicle speed information of the vehicle speed sensor 97.
Further, the ECU 89 determines the degree of cooling of the engine room 3 obtained at that time, that is, the degree of required cooling, based on the history of the vehicle operation state in the past immediately before the engine operation is stopped. (Corresponding to the determination means of the present application) is set. This determination function calculates an average gradient and an average vehicle speed in the past 10 minutes before engine operation stop using, for example, information of a vehicle operation history, and based on the calculated average gradient and the average vehicle speed, Determine

  Specifically, the load condition of the engine 5 is variously determined by comparing the calculated average gradient with a threshold value α of a predetermined gradient value which is a reference for determining the engine load condition, and the calculated average vehicle speed and the engine room The engine room 3 at the time of engine operation stop, the engine 5 and the turbocharger are determined by variously determining the cooling condition of the engine room 3 by comparing with the threshold β and the threshold γ of the predetermined vehicle speed value which is the reference of the introduced wind speed to 3 11 temperature conditions are determined to determine how much cooling is required at the time of engine shutdown. Here, for example, a gradient of 3% is used as the threshold α, and 60 km / h and 80 km / h are used as the threshold β and γ.

  Further, in the ECU 89, a cooling execution function for controlling the respective parts of the main radiator device 67 and the sub radiator device 69 is set by pattern control according to the degree of required cooling. The same function includes a first cooling mode in which "the main radiator fan 73, the sub radiator fan 81 and the circulation pump 85 are operated" and a "second only the sub radiator fan 81 and the circulation pump 85 are operated" in descending order of cooling degree. A cooling mode, a third cooling mode in which "only the main radiator fan 73 and the sub radiator fan 81 operate", and a "fourth cooling mode in which only the sub radiator fan 81 operates" are set.

  The cooling execution function selects a mode from the first to fourth cooling modes based on the determination result of the cooling request condition, and for example, the T / C outlet cooling water temperature is a turbocharger 11 by timer control with 10 min as one cycle. It is set by the function to execute to the temperature which does not require the cooling of the engine room 3 so that the cooling of the engine room 3 can be properly performed even in the immediate situation of any engine stop. Specifically, when the average gradient is larger than a predetermined gradient value (predetermined value), the first cooling mode or the second cooling mode is selected, and when the average gradient is equal to or less than a predetermined gradient value (less than a predetermined value), 3) The cooling mode or the fourth cooling mode is selected. Furthermore, either mode is determined from the comparison between the average vehicle speed and a predetermined vehicle speed value (predetermined value).

  It should be noted that the ECU 89 performs cooling when engine warm-up is not completed when engine operation is stopped, that is, when it is determined that the temperature of the coolant for the engine 5 does not reach the predetermined temperature threshold b in the past 10 min. When it is clear that the operation of the engine 5 is a high load operation when engine operation is stopped and the control is not performed, for example, the average exhaust temperature of the engine 5 in the past 10 min exceeds the temperature value for determining the high load operation, When the integration of the exceeded time exceeds the threshold value c of the predetermined integration value, the setting is made to execute the first cooling mode which brings about the highest cooling unconditionally.

Next, the operation of the engine cooling control device 87 configured as described above will be described with reference to the flowchart shown in FIG. 3 and the plan view of the engine room 3 shown in FIGS. 4 and 5.
The vehicle turns on the I / G switch 101 and starts driving the engine 5, and then travels by performing an accelerator operation and a steering wheel operation. At this time, the turbine wheel 53 of the turbocharger 11 is driven by the exhaust heat energy of the engine 5, and the compressor wheel 49 is further driven. Then, the intake air taken into the engine 5 is pushed into the combustion chamber 29 and the supercharging operation by the turbocharger 11 is performed.

While the vehicle is traveling, the history function of the ECU 89 detects the slope of the road surface, detects the vehicle speed (output of the slope sensor 99 and the vehicle speed sensor 97), and detects the temperature of the coolant of the engine 5 (E / G water temperature sensor). The output of 91) and the temperature of the exhaust gas of the engine 5 are continuously detected (output of the exhaust temperature sensor 95) and recorded as a history.
After traveling, stop the vehicle by operating the brake. Then, immediately after stopping, it is assumed that the idle operation of the engine 5 is stopped by key-off operation of the I / G switch 101 as in step S1.

At this time, if the engine 5 has already been warmed up, the situation of the engine room 3 is first grasped. Then, the determination of the specifics of the cooling in the current engine operation stop state is performed. The process proceeds from step S1 through steps S3 and S5 to step S7. The process starts with determining the load driving condition of the engine 5.
Step S7 calculates the gradient average deg per unit of the climbing gradient in the past 10 minutes until the operation of the engine 5 is stopped from the history of the traveling state of the vehicle, and calculates the gradient average as the threshold α (eg, gradient 3%: predetermined Contrast with From this comparison, it can be grasped how much load the engine 5 has been most recently imposed. Accordingly, the case where the load on the engine 5 which is forced to perform supercharging operation is a large slope traveling or the like, and the case where the load on the engine 5 is a small load on a flat road or the like can be divided.

Here, when it is determined that the uphill traveling is performed immediately before the engine operation stop and the engine load is large, the process proceeds to step S9, and the determination of the ventilation condition of the engine room 3 at the engine operation stop immediately next It will be.
The determination of the degree of ventilation of the engine room 3 is made by determining from the wind speed introduced by the traveling wind from the traveling air inlet 9 to the engine room 3. Therefore, in step S9, the average vehicle speed in the past 10 minutes is calculated from the history of the traveling state of the vehicle, and the average vehicle speed is compared with a threshold value β (for example, 60 km / h) in consideration of low and medium vehicle speed. By this comparison, the degree of increase in the ambient temperature of the engine room 3 can be grasped in consideration of the latest traveling state, such as when the average vehicle speed is low during climbing and the average vehicle speed is relatively high during climbing.

Due to the determination of the load condition of the engine 5 and the determination condition of the traveling wind of the engine room 3, the load on the engine 5 is large and the traveling wind of the engine room 3 can not be expected. It is determined that the cooling state is low and the required cooling is slightly lower than that.
If the heat is the most severe (the engine load is large and traveling wind can not be expected), the process proceeds from step S9 to step S11, and the first cooling capacity is used to cool engine room 3, engine 5, and turbocharger 11; Select the cooling mode. Thus, the ECU 89 operates the main radiator fan 73, the sub radiator fan 81, and the circulation pump 85 as shown in FIG.

  Then, according to the operation of the main radiator fan 73 and the sub radiator fan 81 in which the predetermined time (10 min) is one cycle, the outside air is blown toward each part of the engine 5 and introduced into the engine room 3 (FIG. 4). As a result, the engine 5 and the turbocharger 11 are cooled in contact with the cooling air, and the engine compartment 3 is cooled by forced convection of the cooling air and heat transfer caused by the convection. The turbocharger 11 whose temperature is rising with it is forcibly cooled by the cooling water circulating through the sub radiator 79 and the cooling water passage 59 of the turbocharger 11 (by contact heat transfer). That is, when the heat is severed, both the main radiator system 67 and the sub radiator system 69 are fully operated to lower the ambient temperature of the engine compartment 3 with the highest cooling capacity.

  The operation in the first cooling mode is performed until the T / C outlet cooling water temperature reaches the threshold value a as in step S13. If the T / C outlet cooling water temperature reaches the threshold a, it is determined that the equipment including the engine compartment 3 has been sufficiently cooled, and the main radiator fan 73 of the main radiator device 67 (first cooling circuit unit), sub radiator device The operation of the sub radiator fan 81 and the circulation pump 85 of 69 (second cooling circuit unit) is stopped.

If it is determined in step S9 that the temperature is not severer than the above, the process proceeds to step S15 to select the second cooling mode in order to intensively cool the turbocharger 11, which is the cause of the temperature rise. , Sub radiator fan 81 and circulation pump 85 are operated.
Then, according to the operation of the sub-radiator fan 81 in which the predetermined time (10 minutes) is one cycle, the outside air is blown toward the engine 5 and the cooling air is introduced into the engine room 3. At the same time, the cooling water is circulated to the turbocharger 11 where the temperature rise is significant, and the turbocharger 11 is cooled with emphasis.

As a result, the engine room 3 is sufficiently cooled by the cooling focused on the inside and the outside of the turbocharger 11 to fully operate only the sub radiator device 69, and the ambient temperature of the engine room 3 is lowered. That is, the cooling corresponding to the latest situation of the engine room 3 is performed.
Of course, if the T / C outlet cooling water temperature reaches the threshold a as in step S17, it is determined that the equipment including the engine compartment 3 has been sufficiently cooled, and the sub radiator system 69 (second cooling circuit unit) The operation of the radiator fan 81 and the circulation pump 85 is ended.

On the other hand, if it is determined in step S7 that the vehicle is traveling on a flat road or the like with a small load on the engine 5, the process proceeds to step S19 to determine the degree of ventilation of the engine room 3 at this time.
In step S9, the average vehicle speed in the past 10 minutes is calculated from the history of the traveling state of the vehicle, and the average vehicle speed is compared with a threshold value β (for example, 80 km / h) considering flat traveling. By this comparison, it is possible to grasp how the ambient temperature of the engine room 3 rises when traveling wind can be expected, that is, traveling at a high vehicle speed.

Under the condition that the load of the engine 5 is small and the traveling wind of the engine room 3 can be expected by the judgment of the degree of introduction of the traveling wind of the engine room 3, the judgment of the required cooling is performed.
When the degree of demand for cooling is large (for example, less than 80 km / h), it is determined that the temperature rise of the engine 5 is responsible for the temperature rise of the engine compartment 3 in the engine shutdown condition. In this case, the process proceeds to step S21, the third cooling mode is selected, and only the main radiator fan 73 and the sub radiator fan 81 are operated.

Then, according to the operation of the main radiator fan 73 and the sub radiator fan 81 in which the predetermined time (10 minutes) is one cycle, the outside air is blown toward the engine 5 and introduced into the engine room 3 (similar to FIG. 3).
As a result, the cooling of the engine room 3 is sufficiently performed only by the cooling that focuses on the engine 5 by blowing the cooling air to the engine 5 by the operation of the main radiator fan 73 and the sub radiator fan 81. The ambient temperature drops. That is, cooling corresponding to the immediate situation of the engine room 3 is performed.

Then, in step S23, detection of the T / C cooling water temperature is started (for example, once, the circulation pump 85 is operated). If the T / C outlet cooling water temperature reaches the threshold a as in step S25, it is determined that the equipment including the engine compartment 3 has been sufficiently cooled, and the operation of the main radiator fan 73 and the sub radiator fan 81 is ended.
If it is determined in step S19 that the contribution of the temperature rise of the engine 5 is small, the process proceeds to step S27, the fourth cooling mode is selected, and only the sub radiator fan 81 is operated.

Then, according to the operation of the sub-radiator fan 81 in which the predetermined time (10 minutes) is one cycle, the outside air is blown toward the engine 5 and introduced into the engine room 3 (similar to FIG. 4).
As a result, the cooling of the engine room 3 is sufficiently performed only by the cooling by blowing the cooling air to the engine 5 in the operation of the sub radiator fan 81, and the ambient temperature of the engine room 3 is lowered. That is, cooling corresponding to the immediate situation of the engine room 3 is performed.

Then, in step S29, detection of the T / C cooling water temperature is started as described above. If the T / C outlet cooling water temperature reaches the threshold value a as in step S31, it is determined that the equipment including the engine compartment 3 has been sufficiently cooled, and the operation of the sub radiator fan 81 is ended.
When the engine operation is stopped, if the cooling water temperature of the engine 5 has not reached the threshold a of the cooling water temperature for determining that the warm-up operation has been completed (step S3), the engine cooling is not performed. In addition, when the engine operation is stopped, the average exhaust temperature of the engine 5 in the past 10 minutes exceeds the temperature value for determining high load operation, and the operation of the engine 5 is performed such that the integration of the exceeded time exceeds the threshold c of the predetermined integration value. If it is clear that the operation is a high load operation (step S5), the first cooling mode is performed which brings about the highest cooling unconditionally.

  As described above, when the engine operation is stopped, the main radiator device 67 (first cooling circuit portion) and the sub radiator device 69 (second cooling circuit portion) are controlled based on the traveling state of the vehicle immediately before the stop, so low and middle The engine room 3, the engine 5, and the turbocharger 11 (devices provided in the engine exhaust system) can be properly cooled from any conditions such as stopping from fast running and stopping from fast running.

Therefore, the temperature rise of the engine compartment 3, the engine 5, and the turbocharger 11 (device provided in the engine exhaust system) can be effectively suppressed, and heat damage can be properly dealt with. In particular, it is effective for the engine 5 in which the turbocharger 11 is provided in the exhaust system.
Moreover, gradient information when the vehicle travels uphill and travel information including vehicle speed information of the vehicle are left as a history, and the average slope and the average vehicle speed immediately before stopping the engine are calculated when the engine operation is stopped after traveling uphill. Determines the required cooling degree based on the same average gradient and the same average vehicle speed, and controls the main radiator device 67 (first cooling circuit unit) and the sub radiator device 69 (second cooling circuit unit) based on the same cooling request degree As a result, even if the operation of the engine 5 is stopped after climbing uphill, the engine room 3, the engine 5, and the turbocharger 11 can be properly cooled.

  Moreover, the first cooling mode in which the main radiator fan 73, the sub radiator fan 81 and the circulation pump 85 operate, the second cooling mode in which only the sub radiator fan 81 and the circulation pump 85 operate, only the main radiator fan 73 and the sub radiator fan 81 The mode is selected based on the cooling requirement from among the third cooling mode operated by the second cooling mode and the fourth cooling mode operated only by the sub radiator fan 81, that is, cooling with various cooling capacities depending on the cooling required state Therefore, cooling after engine operation can be performed while suppressing the burden of power consumption. In particular, the first cooling mode or the second cooling mode is selected when the average gradient is larger than the predetermined gradient value (predetermined value), and the third cooling mode or the fourth cooling mode is selected when the average gradient is less than the predetermined gradient value (less than the predetermined value). By selecting the cooling mode, it is possible to select the cooling mode appropriately.

Further, since both the main radiator fan 73 and the sub radiator fan 81 are disposed so that the cooling air blows directly on the engine 5, a horizontally mounted engine in which the turbocharger 11 that is difficult to cool is disposed on the vehicle compartment side Even in the attitude of 5 and engine room 3, cooling can be expected.
In addition, since the sub radiator device 69 is configured by diverting the intercooler cooling device 77, the cost can be reduced with a simple structure.

  The present invention is not limited to the above-described embodiment, and various changes may be made without departing from the scope of the present invention.

3 engine room 5 engine 11 turbocharger (equipment provided in engine exhaust system)
67 Main Radiator Device (First Cooling Circuit)
69 Sub Radiator Device (Second Cooling Circuit)
71 main radiator 73 main radiator fan 79 sub radiator 81 sub radiator fan 84 turbo cooling circuit (sub cooling circuit)
85 circulation pump 89 ECU (history means, judgment means, control means)

Claims (8)

With the engine stored in the engine room,
A first cooling circuit unit having a main radiator for cooling the engine cooling water, and a main radiator fan for blowing a cooling air to the engine room through the main radiator;
A sub-radiator for cooling equipment provided in an exhaust system of the engine, a sub-cooling circuit for circulating a cooling medium by a circulation pump between the equipment and a sub-radiator fan for blowing cooling air to the engine room through the sub-radiator A second cooling circuit unit having
History means for recording, as a history, the traveling state of the vehicle from when the engine is operated to when it is stopped;
A determination unit that determines a degree of required cooling based on latest history information immediately before the stop of the engine when the operation of the engine is stopped;
An engine cooling control device for a vehicle, comprising: control means for controlling the first cooling circuit unit and the second cooling circuit unit based on the determination of the degree of cooling requirement by the determination means. The history means records, as a history, a traveling state including slope information of a road surface when the vehicle travels uphill and vehicle speed information of the vehicle.
The determination means calculates an average slope and an average vehicle speed immediately before the stop of the engine when the operation of the engine is stopped after the vehicle runs uphill, and determines the required cooling degree based on the average slope and the average vehicle speed. Do,
The vehicle according to claim 1, wherein the control unit controls the first cooling circuit unit and the second cooling circuit unit based on a cooling request degree determined by the average gradient and the average vehicle speed. Engine cooling control system. The control unit is configured to, based on the determined degree of cooling requirement,
A first cooling mode in which the main radiator fan of the first cooling circuit unit, the sub radiator fan of the second cooling circuit unit, and the circulation pump operate;
A second cooling mode in which the sub radiator fan and the circulation pump of the second cooling circuit unit operate;
A third cooling mode in which the main radiator fan of the first cooling circuit unit and the sub radiator fan of the second cooling circuit unit operate;
The engine cooling control device for a vehicle according to claim 2, wherein any one of a fourth cooling mode in which the sub radiator fan of the second cooling circuit unit operates is selected. The control unit selects the first cooling mode or the second cooling mode when the average gradient is larger than a predetermined value, and the third cooling mode or the fourth cooling when the average gradient is less than a predetermined value. The engine cooling control device for a vehicle according to claim 3, wherein a mode is selected. The said apparatus is a turbocharger which carries out the supercharging operation of the said engine. The engine cooling control apparatus of the vehicle as described in any one of the Claims 1-4 characterized by the above-mentioned. The engine has an intercooler for cooling intake air supercharged by the turbocharger,
The sub cooling circuit of the second cooling circuit unit is configured such that a flow path of an intercooler cooling device for cooling the intercooler by circulation of the cooling medium is communicated with a cooling water passage of a turbocharger. An engine cooling control device for a vehicle according to claim 5. The vehicle according to any one of claims 1 to 6, wherein the engine is housed in the engine room in a horizontal position in which the turbocharger is located on the vehicle compartment side of the vehicle. Engine cooling control device. The main radiator fan of the first cooling circuit unit and the sub radiator fan of the second cooling circuit unit are both arranged to be blown out so that the cooling air is blown to the engine. An engine cooling control device for a vehicle according to any one of claims 7 to 10.

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